diff options
Diffstat (limited to 'kernel')
80 files changed, 7898 insertions, 2724 deletions
diff --git a/kernel/audit.c b/kernel/audit.c index 906ae5a0233a..34c5a2310fbf 100644 --- a/kernel/audit.c +++ b/kernel/audit.c @@ -41,6 +41,8 @@ * Example user-space utilities: http://people.redhat.com/sgrubb/audit/ */ +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + #include <linux/init.h> #include <asm/types.h> #include <linux/atomic.h> @@ -63,6 +65,7 @@ #include <linux/freezer.h> #include <linux/tty.h> #include <linux/pid_namespace.h> +#include <net/netns/generic.h> #include "audit.h" @@ -76,16 +79,16 @@ static int audit_initialized; #define AUDIT_OFF 0 #define AUDIT_ON 1 #define AUDIT_LOCKED 2 -int audit_enabled; -int audit_ever_enabled; +u32 audit_enabled; +u32 audit_ever_enabled; EXPORT_SYMBOL_GPL(audit_enabled); /* Default state when kernel boots without any parameters. */ -static int audit_default; +static u32 audit_default; /* If auditing cannot proceed, audit_failure selects what happens. */ -static int audit_failure = AUDIT_FAIL_PRINTK; +static u32 audit_failure = AUDIT_FAIL_PRINTK; /* * If audit records are to be written to the netlink socket, audit_pid @@ -93,17 +96,19 @@ static int audit_failure = AUDIT_FAIL_PRINTK; * the portid to use to send netlink messages to that process. */ int audit_pid; -static int audit_nlk_portid; +static __u32 audit_nlk_portid; /* If audit_rate_limit is non-zero, limit the rate of sending audit records * to that number per second. This prevents DoS attacks, but results in * audit records being dropped. */ -static int audit_rate_limit; +static u32 audit_rate_limit; -/* Number of outstanding audit_buffers allowed. */ -static int audit_backlog_limit = 64; -static int audit_backlog_wait_time = 60 * HZ; -static int audit_backlog_wait_overflow = 0; +/* Number of outstanding audit_buffers allowed. + * When set to zero, this means unlimited. */ +static u32 audit_backlog_limit = 64; +#define AUDIT_BACKLOG_WAIT_TIME (60 * HZ) +static u32 audit_backlog_wait_time = AUDIT_BACKLOG_WAIT_TIME; +static u32 audit_backlog_wait_overflow = 0; /* The identity of the user shutting down the audit system. */ kuid_t audit_sig_uid = INVALID_UID; @@ -121,6 +126,7 @@ static atomic_t audit_lost = ATOMIC_INIT(0); /* The netlink socket. */ static struct sock *audit_sock; +int audit_net_id; /* Hash for inode-based rules */ struct list_head audit_inode_hash[AUDIT_INODE_BUCKETS]; @@ -175,27 +181,27 @@ struct audit_buffer { }; struct audit_reply { - int pid; + __u32 portid; + pid_t pid; struct sk_buff *skb; }; -static void audit_set_pid(struct audit_buffer *ab, pid_t pid) +static void audit_set_portid(struct audit_buffer *ab, __u32 portid) { if (ab) { struct nlmsghdr *nlh = nlmsg_hdr(ab->skb); - nlh->nlmsg_pid = pid; + nlh->nlmsg_pid = portid; } } void audit_panic(const char *message) { - switch (audit_failure) - { + switch (audit_failure) { case AUDIT_FAIL_SILENT: break; case AUDIT_FAIL_PRINTK: if (printk_ratelimit()) - printk(KERN_ERR "audit: %s\n", message); + pr_err("%s\n", message); break; case AUDIT_FAIL_PANIC: /* test audit_pid since printk is always losey, why bother? */ @@ -266,9 +272,7 @@ void audit_log_lost(const char *message) if (print) { if (printk_ratelimit()) - printk(KERN_WARNING - "audit: audit_lost=%d audit_rate_limit=%d " - "audit_backlog_limit=%d\n", + pr_warn("audit_lost=%u audit_rate_limit=%u audit_backlog_limit=%u\n", atomic_read(&audit_lost), audit_rate_limit, audit_backlog_limit); @@ -276,7 +280,7 @@ void audit_log_lost(const char *message) } } -static int audit_log_config_change(char *function_name, int new, int old, +static int audit_log_config_change(char *function_name, u32 new, u32 old, int allow_changes) { struct audit_buffer *ab; @@ -285,7 +289,7 @@ static int audit_log_config_change(char *function_name, int new, int old, ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE); if (unlikely(!ab)) return rc; - audit_log_format(ab, "%s=%d old=%d", function_name, new, old); + audit_log_format(ab, "%s=%u old=%u", function_name, new, old); audit_log_session_info(ab); rc = audit_log_task_context(ab); if (rc) @@ -295,9 +299,10 @@ static int audit_log_config_change(char *function_name, int new, int old, return rc; } -static int audit_do_config_change(char *function_name, int *to_change, int new) +static int audit_do_config_change(char *function_name, u32 *to_change, u32 new) { - int allow_changes, rc = 0, old = *to_change; + int allow_changes, rc = 0; + u32 old = *to_change; /* check if we are locked */ if (audit_enabled == AUDIT_LOCKED) @@ -320,17 +325,23 @@ static int audit_do_config_change(char *function_name, int *to_change, int new) return rc; } -static int audit_set_rate_limit(int limit) +static int audit_set_rate_limit(u32 limit) { return audit_do_config_change("audit_rate_limit", &audit_rate_limit, limit); } -static int audit_set_backlog_limit(int limit) +static int audit_set_backlog_limit(u32 limit) { return audit_do_config_change("audit_backlog_limit", &audit_backlog_limit, limit); } -static int audit_set_enabled(int state) +static int audit_set_backlog_wait_time(u32 timeout) +{ + return audit_do_config_change("audit_backlog_wait_time", + &audit_backlog_wait_time, timeout); +} + +static int audit_set_enabled(u32 state) { int rc; if (state < AUDIT_OFF || state > AUDIT_LOCKED) @@ -343,7 +354,7 @@ static int audit_set_enabled(int state) return rc; } -static int audit_set_failure(int state) +static int audit_set_failure(u32 state) { if (state != AUDIT_FAIL_SILENT && state != AUDIT_FAIL_PRINTK @@ -365,7 +376,8 @@ static int audit_set_failure(int state) static void audit_hold_skb(struct sk_buff *skb) { if (audit_default && - skb_queue_len(&audit_skb_hold_queue) < audit_backlog_limit) + (!audit_backlog_limit || + skb_queue_len(&audit_skb_hold_queue) < audit_backlog_limit)) skb_queue_tail(&audit_skb_hold_queue, skb); else kfree_skb(skb); @@ -382,7 +394,7 @@ static void audit_printk_skb(struct sk_buff *skb) if (nlh->nlmsg_type != AUDIT_EOE) { if (printk_ratelimit()) - printk(KERN_NOTICE "type=%d %s\n", nlh->nlmsg_type, data); + pr_notice("type=%d %s\n", nlh->nlmsg_type, data); else audit_log_lost("printk limit exceeded\n"); } @@ -398,9 +410,12 @@ static void kauditd_send_skb(struct sk_buff *skb) err = netlink_unicast(audit_sock, skb, audit_nlk_portid, 0); if (err < 0) { BUG_ON(err != -ECONNREFUSED); /* Shouldn't happen */ - printk(KERN_ERR "audit: *NO* daemon at audit_pid=%d\n", audit_pid); - audit_log_lost("auditd disappeared\n"); - audit_pid = 0; + if (audit_pid) { + pr_err("*NO* daemon at audit_pid=%d\n", audit_pid); + audit_log_lost("auditd disappeared\n"); + audit_pid = 0; + audit_sock = NULL; + } /* we might get lucky and get this in the next auditd */ audit_hold_skb(skb); } else @@ -457,8 +472,10 @@ static int kauditd_thread(void *dummy) flush_hold_queue(); skb = skb_dequeue(&audit_skb_queue); - wake_up(&audit_backlog_wait); + if (skb) { + if (skb_queue_len(&audit_skb_queue) <= audit_backlog_limit) + wake_up(&audit_backlog_wait); if (audit_pid) kauditd_send_skb(skb); else @@ -482,22 +499,23 @@ static int kauditd_thread(void *dummy) int audit_send_list(void *_dest) { struct audit_netlink_list *dest = _dest; - int pid = dest->pid; struct sk_buff *skb; + struct net *net = get_net_ns_by_pid(dest->pid); + struct audit_net *aunet = net_generic(net, audit_net_id); /* wait for parent to finish and send an ACK */ mutex_lock(&audit_cmd_mutex); mutex_unlock(&audit_cmd_mutex); while ((skb = __skb_dequeue(&dest->q)) != NULL) - netlink_unicast(audit_sock, skb, pid, 0); + netlink_unicast(aunet->nlsk, skb, dest->portid, 0); kfree(dest); return 0; } -struct sk_buff *audit_make_reply(int pid, int seq, int type, int done, +struct sk_buff *audit_make_reply(__u32 portid, int seq, int type, int done, int multi, const void *payload, int size) { struct sk_buff *skb; @@ -510,7 +528,7 @@ struct sk_buff *audit_make_reply(int pid, int seq, int type, int done, if (!skb) return NULL; - nlh = nlmsg_put(skb, pid, seq, t, size, flags); + nlh = nlmsg_put(skb, portid, seq, t, size, flags); if (!nlh) goto out_kfree_skb; data = nlmsg_data(nlh); @@ -525,19 +543,21 @@ out_kfree_skb: static int audit_send_reply_thread(void *arg) { struct audit_reply *reply = (struct audit_reply *)arg; + struct net *net = get_net_ns_by_pid(reply->pid); + struct audit_net *aunet = net_generic(net, audit_net_id); mutex_lock(&audit_cmd_mutex); mutex_unlock(&audit_cmd_mutex); /* Ignore failure. It'll only happen if the sender goes away, because our timeout is set to infinite. */ - netlink_unicast(audit_sock, reply->skb, reply->pid, 0); + netlink_unicast(aunet->nlsk , reply->skb, reply->portid, 0); kfree(reply); return 0; } /** * audit_send_reply - send an audit reply message via netlink - * @pid: process id to send reply to + * @portid: netlink port to which to send reply * @seq: sequence number * @type: audit message type * @done: done (last) flag @@ -545,11 +565,11 @@ static int audit_send_reply_thread(void *arg) * @payload: payload data * @size: payload size * - * Allocates an skb, builds the netlink message, and sends it to the pid. + * Allocates an skb, builds the netlink message, and sends it to the port id. * No failure notifications. */ -static void audit_send_reply(int pid, int seq, int type, int done, int multi, - const void *payload, int size) +static void audit_send_reply(__u32 portid, int seq, int type, int done, + int multi, const void *payload, int size) { struct sk_buff *skb; struct task_struct *tsk; @@ -559,11 +579,12 @@ static void audit_send_reply(int pid, int seq, int type, int done, int multi, if (!reply) return; - skb = audit_make_reply(pid, seq, type, done, multi, payload, size); + skb = audit_make_reply(portid, seq, type, done, multi, payload, size); if (!skb) goto out; - reply->pid = pid; + reply->portid = portid; + reply->pid = task_pid_vnr(current); reply->skb = skb; tsk = kthread_run(audit_send_reply_thread, reply, "audit_send_reply"); @@ -663,8 +684,12 @@ static void audit_log_feature_change(int which, u32 old_feature, u32 new_feature { struct audit_buffer *ab; + if (audit_enabled == AUDIT_OFF) + return; + ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_FEATURE_CHANGE); - audit_log_format(ab, "feature=%s new=%d old=%d old_lock=%d new_lock=%d res=%d", + audit_log_task_info(ab, current); + audit_log_format(ab, "feature=%s old=%u new=%u old_lock=%u new_lock=%u res=%d", audit_feature_names[which], !!old_feature, !!new_feature, !!old_lock, !!new_lock, res); audit_log_end(ab); @@ -694,7 +719,7 @@ static int audit_set_feature(struct sk_buff *skb) old_lock = af.lock & feature; /* are we changing a locked feature? */ - if ((af.lock & feature) && (new_feature != old_feature)) { + if (old_lock && (new_feature != old_feature)) { audit_log_feature_change(i, old_feature, new_feature, old_lock, new_lock, 0); return -EPERM; @@ -732,7 +757,6 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh) { u32 seq; void *data; - struct audit_status *status_get, status_set; int err; struct audit_buffer *ab; u16 msg_type = nlh->nlmsg_type; @@ -758,48 +782,70 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh) data = nlmsg_data(nlh); switch (msg_type) { - case AUDIT_GET: - memset(&status_set, 0, sizeof(status_set)); - status_set.enabled = audit_enabled; - status_set.failure = audit_failure; - status_set.pid = audit_pid; - status_set.rate_limit = audit_rate_limit; - status_set.backlog_limit = audit_backlog_limit; - status_set.lost = atomic_read(&audit_lost); - status_set.backlog = skb_queue_len(&audit_skb_queue); + case AUDIT_GET: { + struct audit_status s; + memset(&s, 0, sizeof(s)); + s.enabled = audit_enabled; + s.failure = audit_failure; + s.pid = audit_pid; + s.rate_limit = audit_rate_limit; + s.backlog_limit = audit_backlog_limit; + s.lost = atomic_read(&audit_lost); + s.backlog = skb_queue_len(&audit_skb_queue); + s.version = AUDIT_VERSION_LATEST; + s.backlog_wait_time = audit_backlog_wait_time; audit_send_reply(NETLINK_CB(skb).portid, seq, AUDIT_GET, 0, 0, - &status_set, sizeof(status_set)); + &s, sizeof(s)); break; - case AUDIT_SET: - if (nlmsg_len(nlh) < sizeof(struct audit_status)) - return -EINVAL; - status_get = (struct audit_status *)data; - if (status_get->mask & AUDIT_STATUS_ENABLED) { - err = audit_set_enabled(status_get->enabled); + } + case AUDIT_SET: { + struct audit_status s; + memset(&s, 0, sizeof(s)); + /* guard against past and future API changes */ + memcpy(&s, data, min_t(size_t, sizeof(s), nlmsg_len(nlh))); + if (s.mask & AUDIT_STATUS_ENABLED) { + err = audit_set_enabled(s.enabled); if (err < 0) return err; } - if (status_get->mask & AUDIT_STATUS_FAILURE) { - err = audit_set_failure(status_get->failure); + if (s.mask & AUDIT_STATUS_FAILURE) { + err = audit_set_failure(s.failure); if (err < 0) return err; } - if (status_get->mask & AUDIT_STATUS_PID) { - int new_pid = status_get->pid; + if (s.mask & AUDIT_STATUS_PID) { + int new_pid = s.pid; + if ((!new_pid) && (task_tgid_vnr(current) != audit_pid)) + return -EACCES; if (audit_enabled != AUDIT_OFF) audit_log_config_change("audit_pid", new_pid, audit_pid, 1); audit_pid = new_pid; audit_nlk_portid = NETLINK_CB(skb).portid; + audit_sock = skb->sk; } - if (status_get->mask & AUDIT_STATUS_RATE_LIMIT) { - err = audit_set_rate_limit(status_get->rate_limit); + if (s.mask & AUDIT_STATUS_RATE_LIMIT) { + err = audit_set_rate_limit(s.rate_limit); + if (err < 0) + return err; + } + if (s.mask & AUDIT_STATUS_BACKLOG_LIMIT) { + err = audit_set_backlog_limit(s.backlog_limit); + if (err < 0) + return err; + } + if (s.mask & AUDIT_STATUS_BACKLOG_WAIT_TIME) { + if (sizeof(s) > (size_t)nlh->nlmsg_len) + return -EINVAL; + if (s.backlog_wait_time < 0 || + s.backlog_wait_time > 10*AUDIT_BACKLOG_WAIT_TIME) + return -EINVAL; + err = audit_set_backlog_wait_time(s.backlog_wait_time); if (err < 0) return err; } - if (status_get->mask & AUDIT_STATUS_BACKLOG_LIMIT) - err = audit_set_backlog_limit(status_get->backlog_limit); break; + } case AUDIT_GET_FEATURE: err = audit_get_feature(skb); if (err) @@ -817,13 +863,14 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh) return 0; err = audit_filter_user(msg_type); - if (err == 1) { + if (err == 1) { /* match or error */ err = 0; if (msg_type == AUDIT_USER_TTY) { err = tty_audit_push_current(); if (err) break; } + mutex_unlock(&audit_cmd_mutex); audit_log_common_recv_msg(&ab, msg_type); if (msg_type != AUDIT_USER_TTY) audit_log_format(ab, " msg='%.*s'", @@ -839,8 +886,9 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh) size--; audit_log_n_untrustedstring(ab, data, size); } - audit_set_pid(ab, NETLINK_CB(skb).portid); + audit_set_portid(ab, NETLINK_CB(skb).portid); audit_log_end(ab); + mutex_lock(&audit_cmd_mutex); } break; case AUDIT_ADD_RULE: @@ -853,11 +901,12 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh) audit_log_end(ab); return -EPERM; } - /* fallthrough */ - case AUDIT_LIST_RULES: - err = audit_receive_filter(msg_type, NETLINK_CB(skb).portid, + err = audit_rule_change(msg_type, NETLINK_CB(skb).portid, seq, data, nlmsg_len(nlh)); break; + case AUDIT_LIST_RULES: + err = audit_list_rules_send(NETLINK_CB(skb).portid, seq); + break; case AUDIT_TRIM: audit_trim_trees(); audit_log_common_recv_msg(&ab, AUDIT_CONFIG_CHANGE); @@ -939,20 +988,33 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh) break; } case AUDIT_TTY_SET: { - struct audit_tty_status s; + struct audit_tty_status s, old; struct task_struct *tsk = current; + struct audit_buffer *ab; memset(&s, 0, sizeof(s)); /* guard against past and future API changes */ memcpy(&s, data, min_t(size_t, sizeof(s), nlmsg_len(nlh))); + /* check if new data is valid */ if ((s.enabled != 0 && s.enabled != 1) || (s.log_passwd != 0 && s.log_passwd != 1)) - return -EINVAL; + err = -EINVAL; spin_lock(&tsk->sighand->siglock); - tsk->signal->audit_tty = s.enabled; - tsk->signal->audit_tty_log_passwd = s.log_passwd; + old.enabled = tsk->signal->audit_tty; + old.log_passwd = tsk->signal->audit_tty_log_passwd; + if (!err) { + tsk->signal->audit_tty = s.enabled; + tsk->signal->audit_tty_log_passwd = s.log_passwd; + } spin_unlock(&tsk->sighand->siglock); + + audit_log_common_recv_msg(&ab, AUDIT_CONFIG_CHANGE); + audit_log_format(ab, " op=tty_set old-enabled=%d new-enabled=%d" + " old-log_passwd=%d new-log_passwd=%d res=%d", + old.enabled, s.enabled, old.log_passwd, + s.log_passwd, !err); + audit_log_end(ab); break; } default: @@ -998,24 +1060,55 @@ static void audit_receive(struct sk_buff *skb) mutex_unlock(&audit_cmd_mutex); } -/* Initialize audit support at boot time. */ -static int __init audit_init(void) +static int __net_init audit_net_init(struct net *net) { - int i; struct netlink_kernel_cfg cfg = { .input = audit_receive, }; + struct audit_net *aunet = net_generic(net, audit_net_id); + + aunet->nlsk = netlink_kernel_create(net, NETLINK_AUDIT, &cfg); + if (aunet->nlsk == NULL) { + audit_panic("cannot initialize netlink socket in namespace"); + return -ENOMEM; + } + aunet->nlsk->sk_sndtimeo = MAX_SCHEDULE_TIMEOUT; + return 0; +} + +static void __net_exit audit_net_exit(struct net *net) +{ + struct audit_net *aunet = net_generic(net, audit_net_id); + struct sock *sock = aunet->nlsk; + if (sock == audit_sock) { + audit_pid = 0; + audit_sock = NULL; + } + + rcu_assign_pointer(aunet->nlsk, NULL); + synchronize_net(); + netlink_kernel_release(sock); +} + +static struct pernet_operations audit_net_ops __net_initdata = { + .init = audit_net_init, + .exit = audit_net_exit, + .id = &audit_net_id, + .size = sizeof(struct audit_net), +}; + +/* Initialize audit support at boot time. */ +static int __init audit_init(void) +{ + int i; + if (audit_initialized == AUDIT_DISABLED) return 0; - printk(KERN_INFO "audit: initializing netlink socket (%s)\n", - audit_default ? "enabled" : "disabled"); - audit_sock = netlink_kernel_create(&init_net, NETLINK_AUDIT, &cfg); - if (!audit_sock) - audit_panic("cannot initialize netlink socket"); - else - audit_sock->sk_sndtimeo = MAX_SCHEDULE_TIMEOUT; + pr_info("initializing netlink subsys (%s)\n", + audit_default ? "enabled" : "disabled"); + register_pernet_subsys(&audit_net_ops); skb_queue_head_init(&audit_skb_queue); skb_queue_head_init(&audit_skb_hold_queue); @@ -1039,22 +1132,32 @@ static int __init audit_enable(char *str) if (!audit_default) audit_initialized = AUDIT_DISABLED; - printk(KERN_INFO "audit: %s", audit_default ? "enabled" : "disabled"); + pr_info("%s\n", audit_default ? + "enabled (after initialization)" : "disabled (until reboot)"); - if (audit_initialized == AUDIT_INITIALIZED) { - audit_enabled = audit_default; - audit_ever_enabled |= !!audit_default; - } else if (audit_initialized == AUDIT_UNINITIALIZED) { - printk(" (after initialization)"); - } else { - printk(" (until reboot)"); + return 1; +} +__setup("audit=", audit_enable); + +/* Process kernel command-line parameter at boot time. + * audit_backlog_limit=<n> */ +static int __init audit_backlog_limit_set(char *str) +{ + u32 audit_backlog_limit_arg; + + pr_info("audit_backlog_limit: "); + if (kstrtouint(str, 0, &audit_backlog_limit_arg)) { + pr_cont("using default of %u, unable to parse %s\n", + audit_backlog_limit, str); + return 1; } - printk("\n"); + + audit_backlog_limit = audit_backlog_limit_arg; + pr_cont("%d\n", audit_backlog_limit); return 1; } - -__setup("audit=", audit_enable); +__setup("audit_backlog_limit=", audit_backlog_limit_set); static void audit_buffer_free(struct audit_buffer *ab) { @@ -1165,18 +1268,20 @@ static inline void audit_get_stamp(struct audit_context *ctx, /* * Wait for auditd to drain the queue a little */ -static void wait_for_auditd(unsigned long sleep_time) +static long wait_for_auditd(long sleep_time) { DECLARE_WAITQUEUE(wait, current); set_current_state(TASK_UNINTERRUPTIBLE); - add_wait_queue(&audit_backlog_wait, &wait); + add_wait_queue_exclusive(&audit_backlog_wait, &wait); if (audit_backlog_limit && skb_queue_len(&audit_skb_queue) > audit_backlog_limit) - schedule_timeout(sleep_time); + sleep_time = schedule_timeout(sleep_time); __set_current_state(TASK_RUNNING); remove_wait_queue(&audit_backlog_wait, &wait); + + return sleep_time; } /** @@ -1200,7 +1305,8 @@ struct audit_buffer *audit_log_start(struct audit_context *ctx, gfp_t gfp_mask, struct audit_buffer *ab = NULL; struct timespec t; unsigned int uninitialized_var(serial); - int reserve; + int reserve = 5; /* Allow atomic callers to go up to five + entries over the normal backlog limit */ unsigned long timeout_start = jiffies; if (audit_initialized != AUDIT_INITIALIZED) @@ -1209,36 +1315,37 @@ struct audit_buffer *audit_log_start(struct audit_context *ctx, gfp_t gfp_mask, if (unlikely(audit_filter_type(type))) return NULL; - if (gfp_mask & __GFP_WAIT) - reserve = 0; - else - reserve = 5; /* Allow atomic callers to go up to five - entries over the normal backlog limit */ + if (gfp_mask & __GFP_WAIT) { + if (audit_pid && audit_pid == current->pid) + gfp_mask &= ~__GFP_WAIT; + else + reserve = 0; + } while (audit_backlog_limit && skb_queue_len(&audit_skb_queue) > audit_backlog_limit + reserve) { if (gfp_mask & __GFP_WAIT && audit_backlog_wait_time) { - unsigned long sleep_time; + long sleep_time; - sleep_time = timeout_start + audit_backlog_wait_time - - jiffies; - if ((long)sleep_time > 0) { - wait_for_auditd(sleep_time); - continue; + sleep_time = timeout_start + audit_backlog_wait_time - jiffies; + if (sleep_time > 0) { + sleep_time = wait_for_auditd(sleep_time); + if (sleep_time > 0) + continue; } } if (audit_rate_check() && printk_ratelimit()) - printk(KERN_WARNING - "audit: audit_backlog=%d > " - "audit_backlog_limit=%d\n", - skb_queue_len(&audit_skb_queue), - audit_backlog_limit); + pr_warn("audit_backlog=%d > audit_backlog_limit=%d\n", + skb_queue_len(&audit_skb_queue), + audit_backlog_limit); audit_log_lost("backlog limit exceeded"); audit_backlog_wait_time = audit_backlog_wait_overflow; wake_up(&audit_backlog_wait); return NULL; } + audit_backlog_wait_time = AUDIT_BACKLOG_WAIT_TIME; + ab = audit_buffer_alloc(ctx, gfp_mask, type); if (!ab) { audit_log_lost("out of memory in audit_log_start"); @@ -1356,7 +1463,6 @@ void audit_log_n_hex(struct audit_buffer *ab, const unsigned char *buf, int i, avail, new_len; unsigned char *ptr; struct sk_buff *skb; - static const unsigned char *hex = "0123456789ABCDEF"; if (!ab) return; @@ -1374,10 +1480,8 @@ void audit_log_n_hex(struct audit_buffer *ab, const unsigned char *buf, } ptr = skb_tail_pointer(skb); - for (i=0; i<len; i++) { - *ptr++ = hex[(buf[i] & 0xF0)>>4]; /* Upper nibble */ - *ptr++ = hex[buf[i] & 0x0F]; /* Lower nibble */ - } + for (i = 0; i < len; i++) + ptr = hex_byte_pack_upper(ptr, buf[i]); *ptr = 0; skb_put(skb, len << 1); /* new string is twice the old string */ } @@ -1491,7 +1595,7 @@ void audit_log_d_path(struct audit_buffer *ab, const char *prefix, void audit_log_session_info(struct audit_buffer *ab) { - u32 sessionid = audit_get_sessionid(current); + unsigned int sessionid = audit_get_sessionid(current); uid_t auid = from_kuid(&init_user_ns, audit_get_loginuid(current)); audit_log_format(ab, " auid=%u ses=%u", auid, sessionid); @@ -1716,7 +1820,7 @@ void audit_log_task_info(struct audit_buffer *ab, struct task_struct *tsk) audit_log_format(ab, " ppid=%ld pid=%d auid=%u uid=%u gid=%u" " euid=%u suid=%u fsuid=%u" - " egid=%u sgid=%u fsgid=%u ses=%u tty=%s", + " egid=%u sgid=%u fsgid=%u tty=%s ses=%u", sys_getppid(), tsk->pid, from_kuid(&init_user_ns, audit_get_loginuid(tsk)), @@ -1728,7 +1832,7 @@ void audit_log_task_info(struct audit_buffer *ab, struct task_struct *tsk) from_kgid(&init_user_ns, cred->egid), from_kgid(&init_user_ns, cred->sgid), from_kgid(&init_user_ns, cred->fsgid), - audit_get_sessionid(tsk), tty); + tty, audit_get_sessionid(tsk)); get_task_comm(name, tsk); audit_log_format(ab, " comm="); @@ -1739,7 +1843,8 @@ void audit_log_task_info(struct audit_buffer *ab, struct task_struct *tsk) if (mm->exe_file) audit_log_d_path(ab, " exe=", &mm->exe_file->f_path); up_read(&mm->mmap_sem); - } + } else + audit_log_format(ab, " exe=(null)"); audit_log_task_context(ab); } EXPORT_SYMBOL(audit_log_task_info); diff --git a/kernel/audit.h b/kernel/audit.h index b779642b29af..57cc64d67718 100644 --- a/kernel/audit.h +++ b/kernel/audit.h @@ -209,7 +209,7 @@ struct audit_context { #endif }; -extern int audit_ever_enabled; +extern u32 audit_ever_enabled; extern void audit_copy_inode(struct audit_names *name, const struct dentry *dentry, @@ -240,18 +240,23 @@ extern int audit_uid_comparator(kuid_t left, u32 op, kuid_t right); extern int audit_gid_comparator(kgid_t left, u32 op, kgid_t right); extern int parent_len(const char *path); extern int audit_compare_dname_path(const char *dname, const char *path, int plen); -extern struct sk_buff * audit_make_reply(int pid, int seq, int type, - int done, int multi, - const void *payload, int size); +extern struct sk_buff *audit_make_reply(__u32 portid, int seq, int type, + int done, int multi, + const void *payload, int size); extern void audit_panic(const char *message); struct audit_netlink_list { - int pid; + __u32 portid; + pid_t pid; struct sk_buff_head q; }; int audit_send_list(void *); +struct audit_net { + struct sock *nlsk; +}; + extern int selinux_audit_rule_update(void); extern struct mutex audit_filter_mutex; diff --git a/kernel/audit_tree.c b/kernel/audit_tree.c index 43c307dc9453..67ccf0e7cca9 100644 --- a/kernel/audit_tree.c +++ b/kernel/audit_tree.c @@ -912,12 +912,13 @@ static void evict_chunk(struct audit_chunk *chunk) } static int audit_tree_handle_event(struct fsnotify_group *group, + struct inode *to_tell, struct fsnotify_mark *inode_mark, - struct fsnotify_mark *vfsmonut_mark, - struct fsnotify_event *event) + struct fsnotify_mark *vfsmount_mark, + u32 mask, void *data, int data_type, + const unsigned char *file_name) { - BUG(); - return -EOPNOTSUPP; + return 0; } static void audit_tree_freeing_mark(struct fsnotify_mark *entry, struct fsnotify_group *group) @@ -933,19 +934,8 @@ static void audit_tree_freeing_mark(struct fsnotify_mark *entry, struct fsnotify BUG_ON(atomic_read(&entry->refcnt) < 1); } -static bool audit_tree_send_event(struct fsnotify_group *group, struct inode *inode, - struct fsnotify_mark *inode_mark, - struct fsnotify_mark *vfsmount_mark, - __u32 mask, void *data, int data_type) -{ - return false; -} - static const struct fsnotify_ops audit_tree_ops = { .handle_event = audit_tree_handle_event, - .should_send_event = audit_tree_send_event, - .free_group_priv = NULL, - .free_event_priv = NULL, .freeing_mark = audit_tree_freeing_mark, }; diff --git a/kernel/audit_watch.c b/kernel/audit_watch.c index 22831c4d369c..2596fac5dcb4 100644 --- a/kernel/audit_watch.c +++ b/kernel/audit_watch.c @@ -465,35 +465,27 @@ void audit_remove_watch_rule(struct audit_krule *krule) } } -static bool audit_watch_should_send_event(struct fsnotify_group *group, struct inode *inode, - struct fsnotify_mark *inode_mark, - struct fsnotify_mark *vfsmount_mark, - __u32 mask, void *data, int data_type) -{ - return true; -} - /* Update watch data in audit rules based on fsnotify events. */ static int audit_watch_handle_event(struct fsnotify_group *group, + struct inode *to_tell, struct fsnotify_mark *inode_mark, struct fsnotify_mark *vfsmount_mark, - struct fsnotify_event *event) + u32 mask, void *data, int data_type, + const unsigned char *dname) { struct inode *inode; - __u32 mask = event->mask; - const char *dname = event->file_name; struct audit_parent *parent; parent = container_of(inode_mark, struct audit_parent, mark); BUG_ON(group != audit_watch_group); - switch (event->data_type) { + switch (data_type) { case (FSNOTIFY_EVENT_PATH): - inode = event->path.dentry->d_inode; + inode = ((struct path *)data)->dentry->d_inode; break; case (FSNOTIFY_EVENT_INODE): - inode = event->inode; + inode = (struct inode *)data; break; default: BUG(); @@ -512,11 +504,7 @@ static int audit_watch_handle_event(struct fsnotify_group *group, } static const struct fsnotify_ops audit_watch_fsnotify_ops = { - .should_send_event = audit_watch_should_send_event, .handle_event = audit_watch_handle_event, - .free_group_priv = NULL, - .freeing_mark = NULL, - .free_event_priv = NULL, }; static int __init audit_watch_init(void) diff --git a/kernel/auditfilter.c b/kernel/auditfilter.c index 51f3fd4c1ed3..14a78cca384e 100644 --- a/kernel/auditfilter.c +++ b/kernel/auditfilter.c @@ -972,7 +972,7 @@ out: } /* List rules using struct audit_rule_data. */ -static void audit_list_rules(int pid, int seq, struct sk_buff_head *q) +static void audit_list_rules(__u32 portid, int seq, struct sk_buff_head *q) { struct sk_buff *skb; struct audit_krule *r; @@ -987,14 +987,15 @@ static void audit_list_rules(int pid, int seq, struct sk_buff_head *q) data = audit_krule_to_data(r); if (unlikely(!data)) break; - skb = audit_make_reply(pid, seq, AUDIT_LIST_RULES, 0, 1, - data, sizeof(*data) + data->buflen); + skb = audit_make_reply(portid, seq, AUDIT_LIST_RULES, + 0, 1, data, + sizeof(*data) + data->buflen); if (skb) skb_queue_tail(q, skb); kfree(data); } } - skb = audit_make_reply(pid, seq, AUDIT_LIST_RULES, 1, 1, NULL, 0); + skb = audit_make_reply(portid, seq, AUDIT_LIST_RULES, 1, 1, NULL, 0); if (skb) skb_queue_tail(q, skb); } @@ -1004,7 +1005,7 @@ static void audit_log_rule_change(char *action, struct audit_krule *rule, int re { struct audit_buffer *ab; uid_t loginuid = from_kuid(&init_user_ns, audit_get_loginuid(current)); - u32 sessionid = audit_get_sessionid(current); + unsigned int sessionid = audit_get_sessionid(current); if (!audit_enabled) return; @@ -1022,45 +1023,20 @@ static void audit_log_rule_change(char *action, struct audit_krule *rule, int re } /** - * audit_receive_filter - apply all rules to the specified message type + * audit_rule_change - apply all rules to the specified message type * @type: audit message type - * @pid: target pid for netlink audit messages + * @portid: target port id for netlink audit messages * @seq: netlink audit message sequence (serial) number * @data: payload data * @datasz: size of payload data */ -int audit_receive_filter(int type, int pid, int seq, void *data, size_t datasz) +int audit_rule_change(int type, __u32 portid, int seq, void *data, + size_t datasz) { - struct task_struct *tsk; - struct audit_netlink_list *dest; int err = 0; struct audit_entry *entry; switch (type) { - case AUDIT_LIST_RULES: - /* We can't just spew out the rules here because we might fill - * the available socket buffer space and deadlock waiting for - * auditctl to read from it... which isn't ever going to - * happen if we're actually running in the context of auditctl - * trying to _send_ the stuff */ - - dest = kmalloc(sizeof(struct audit_netlink_list), GFP_KERNEL); - if (!dest) - return -ENOMEM; - dest->pid = pid; - skb_queue_head_init(&dest->q); - - mutex_lock(&audit_filter_mutex); - audit_list_rules(pid, seq, &dest->q); - mutex_unlock(&audit_filter_mutex); - - tsk = kthread_run(audit_send_list, dest, "audit_send_list"); - if (IS_ERR(tsk)) { - skb_queue_purge(&dest->q); - kfree(dest); - err = PTR_ERR(tsk); - } - break; case AUDIT_ADD_RULE: entry = audit_data_to_entry(data, datasz); if (IS_ERR(entry)) @@ -1087,6 +1063,44 @@ int audit_receive_filter(int type, int pid, int seq, void *data, size_t datasz) return err; } +/** + * audit_list_rules_send - list the audit rules + * @portid: target portid for netlink audit messages + * @seq: netlink audit message sequence (serial) number + */ +int audit_list_rules_send(__u32 portid, int seq) +{ + struct task_struct *tsk; + struct audit_netlink_list *dest; + int err = 0; + + /* We can't just spew out the rules here because we might fill + * the available socket buffer space and deadlock waiting for + * auditctl to read from it... which isn't ever going to + * happen if we're actually running in the context of auditctl + * trying to _send_ the stuff */ + + dest = kmalloc(sizeof(struct audit_netlink_list), GFP_KERNEL); + if (!dest) + return -ENOMEM; + dest->portid = portid; + dest->pid = task_pid_vnr(current); + skb_queue_head_init(&dest->q); + + mutex_lock(&audit_filter_mutex); + audit_list_rules(portid, seq, &dest->q); + mutex_unlock(&audit_filter_mutex); + + tsk = kthread_run(audit_send_list, dest, "audit_send_list"); + if (IS_ERR(tsk)) { + skb_queue_purge(&dest->q); + kfree(dest); + err = PTR_ERR(tsk); + } + + return err; +} + int audit_comparator(u32 left, u32 op, u32 right) { switch (op) { @@ -1276,19 +1290,22 @@ int audit_filter_user(int type) { enum audit_state state = AUDIT_DISABLED; struct audit_entry *e; - int ret = 1; + int rc, ret; + + ret = 1; /* Audit by default */ rcu_read_lock(); list_for_each_entry_rcu(e, &audit_filter_list[AUDIT_FILTER_USER], list) { - if (audit_filter_user_rules(&e->rule, type, &state)) { - if (state == AUDIT_DISABLED) + rc = audit_filter_user_rules(&e->rule, type, &state); + if (rc) { + if (rc > 0 && state == AUDIT_DISABLED) ret = 0; break; } } rcu_read_unlock(); - return ret; /* Audit by default */ + return ret; } int audit_filter_type(int type) diff --git a/kernel/auditsc.c b/kernel/auditsc.c index 90594c9f7552..10176cd5956a 100644 --- a/kernel/auditsc.c +++ b/kernel/auditsc.c @@ -1969,18 +1969,24 @@ static void audit_log_set_loginuid(kuid_t koldloginuid, kuid_t kloginuid, int rc) { struct audit_buffer *ab; - uid_t uid, ologinuid, nloginuid; + uid_t uid, oldloginuid, loginuid; + + if (!audit_enabled) + return; uid = from_kuid(&init_user_ns, task_uid(current)); - ologinuid = from_kuid(&init_user_ns, koldloginuid); - nloginuid = from_kuid(&init_user_ns, kloginuid), + oldloginuid = from_kuid(&init_user_ns, koldloginuid); + loginuid = from_kuid(&init_user_ns, kloginuid), ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_LOGIN); if (!ab) return; - audit_log_format(ab, "pid=%d uid=%u old auid=%u new auid=%u old " - "ses=%u new ses=%u res=%d", current->pid, uid, ologinuid, - nloginuid, oldsessionid, sessionid, !rc); + audit_log_format(ab, "pid=%d uid=%u" + " old-auid=%u new-auid=%u old-ses=%u new-ses=%u" + " res=%d", + current->pid, uid, + oldloginuid, loginuid, oldsessionid, sessionid, + !rc); audit_log_end(ab); } @@ -2008,7 +2014,7 @@ int audit_set_loginuid(kuid_t loginuid) /* are we setting or clearing? */ if (uid_valid(loginuid)) - sessionid = atomic_inc_return(&session_id); + sessionid = (unsigned int)atomic_inc_return(&session_id); task->sessionid = sessionid; task->loginuid = loginuid; @@ -2321,18 +2327,16 @@ int __audit_log_bprm_fcaps(struct linux_binprm *bprm, /** * __audit_log_capset - store information about the arguments to the capset syscall - * @pid: target pid of the capset call * @new: the new credentials * @old: the old (current) credentials * * Record the aguments userspace sent to sys_capset for later printing by the * audit system if applicable */ -void __audit_log_capset(pid_t pid, - const struct cred *new, const struct cred *old) +void __audit_log_capset(const struct cred *new, const struct cred *old) { struct audit_context *context = current->audit_context; - context->capset.pid = pid; + context->capset.pid = task_pid_nr(current); context->capset.cap.effective = new->cap_effective; context->capset.cap.inheritable = new->cap_effective; context->capset.cap.permitted = new->cap_permitted; @@ -2352,6 +2356,7 @@ static void audit_log_task(struct audit_buffer *ab) kuid_t auid, uid; kgid_t gid; unsigned int sessionid; + struct mm_struct *mm = current->mm; auid = audit_get_loginuid(current); sessionid = audit_get_sessionid(current); @@ -2365,15 +2370,15 @@ static void audit_log_task(struct audit_buffer *ab) audit_log_task_context(ab); audit_log_format(ab, " pid=%d comm=", current->pid); audit_log_untrustedstring(ab, current->comm); + if (mm) { + down_read(&mm->mmap_sem); + if (mm->exe_file) + audit_log_d_path(ab, " exe=", &mm->exe_file->f_path); + up_read(&mm->mmap_sem); + } else + audit_log_format(ab, " exe=(null)"); } -static void audit_log_abend(struct audit_buffer *ab, char *reason, long signr) -{ - audit_log_task(ab); - audit_log_format(ab, " reason="); - audit_log_string(ab, reason); - audit_log_format(ab, " sig=%ld", signr); -} /** * audit_core_dumps - record information about processes that end abnormally * @signr: signal value @@ -2394,7 +2399,8 @@ void audit_core_dumps(long signr) ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_ANOM_ABEND); if (unlikely(!ab)) return; - audit_log_abend(ab, "memory violation", signr); + audit_log_task(ab); + audit_log_format(ab, " sig=%ld", signr); audit_log_end(ab); } diff --git a/kernel/capability.c b/kernel/capability.c index 4e66bf9275b0..34019c57888d 100644 --- a/kernel/capability.c +++ b/kernel/capability.c @@ -277,7 +277,7 @@ SYSCALL_DEFINE2(capset, cap_user_header_t, header, const cap_user_data_t, data) if (ret < 0) goto error; - audit_log_capset(pid, new, current_cred()); + audit_log_capset(new, current_cred()); return commit_creds(new); diff --git a/kernel/cgroup.c b/kernel/cgroup.c index bc1dcabe9217..e2f46ba37f72 100644 --- a/kernel/cgroup.c +++ b/kernel/cgroup.c @@ -41,7 +41,6 @@ #include <linux/rcupdate.h> #include <linux/sched.h> #include <linux/backing-dev.h> -#include <linux/seq_file.h> #include <linux/slab.h> #include <linux/magic.h> #include <linux/spinlock.h> @@ -56,15 +55,20 @@ #include <linux/pid_namespace.h> #include <linux/idr.h> #include <linux/vmalloc.h> /* TODO: replace with more sophisticated array */ -#include <linux/eventfd.h> -#include <linux/poll.h> #include <linux/flex_array.h> /* used in cgroup_attach_task */ #include <linux/kthread.h> -#include <linux/file.h> #include <linux/atomic.h> /* + * pidlists linger the following amount before being destroyed. The goal + * is avoiding frequent destruction in the middle of consecutive read calls + * Expiring in the middle is a performance problem not a correctness one. + * 1 sec should be enough. + */ +#define CGROUP_PIDLIST_DESTROY_DELAY HZ + +/* * cgroup_mutex is the master lock. Any modification to cgroup or its * hierarchy must be performed while holding it. * @@ -89,6 +93,19 @@ static DEFINE_MUTEX(cgroup_mutex); static DEFINE_MUTEX(cgroup_root_mutex); +#define cgroup_assert_mutex_or_rcu_locked() \ + rcu_lockdep_assert(rcu_read_lock_held() || \ + lockdep_is_held(&cgroup_mutex), \ + "cgroup_mutex or RCU read lock required"); + +#ifdef CONFIG_LOCKDEP +#define cgroup_assert_mutex_or_root_locked() \ + WARN_ON_ONCE(debug_locks && (!lockdep_is_held(&cgroup_mutex) && \ + !lockdep_is_held(&cgroup_root_mutex))) +#else +#define cgroup_assert_mutex_or_root_locked() do { } while (0) +#endif + /* * cgroup destruction makes heavy use of work items and there can be a lot * of concurrent destructions. Use a separate workqueue so that cgroup @@ -98,6 +115,12 @@ static DEFINE_MUTEX(cgroup_root_mutex); static struct workqueue_struct *cgroup_destroy_wq; /* + * pidlist destructions need to be flushed on cgroup destruction. Use a + * separate workqueue as flush domain. + */ +static struct workqueue_struct *cgroup_pidlist_destroy_wq; + +/* * Generate an array of cgroup subsystem pointers. At boot time, this is * populated with the built in subsystems, and modular subsystems are * registered after that. The mutable section of this array is protected by @@ -119,49 +142,6 @@ static struct cgroupfs_root cgroup_dummy_root; /* dummy_top is a shorthand for the dummy hierarchy's top cgroup */ static struct cgroup * const cgroup_dummy_top = &cgroup_dummy_root.top_cgroup; -/* - * cgroupfs file entry, pointed to from leaf dentry->d_fsdata. - */ -struct cfent { - struct list_head node; - struct dentry *dentry; - struct cftype *type; - struct cgroup_subsys_state *css; - - /* file xattrs */ - struct simple_xattrs xattrs; -}; - -/* - * cgroup_event represents events which userspace want to receive. - */ -struct cgroup_event { - /* - * css which the event belongs to. - */ - struct cgroup_subsys_state *css; - /* - * Control file which the event associated. - */ - struct cftype *cft; - /* - * eventfd to signal userspace about the event. - */ - struct eventfd_ctx *eventfd; - /* - * Each of these stored in a list by the cgroup. - */ - struct list_head list; - /* - * All fields below needed to unregister event when - * userspace closes eventfd. - */ - poll_table pt; - wait_queue_head_t *wqh; - wait_queue_t wait; - struct work_struct remove; -}; - /* The list of hierarchy roots */ static LIST_HEAD(cgroup_roots); @@ -200,6 +180,7 @@ static int cgroup_destroy_locked(struct cgroup *cgrp); static int cgroup_addrm_files(struct cgroup *cgrp, struct cftype cfts[], bool is_add); static int cgroup_file_release(struct inode *inode, struct file *file); +static void cgroup_pidlist_destroy_all(struct cgroup *cgrp); /** * cgroup_css - obtain a cgroup's css for the specified subsystem @@ -262,16 +243,32 @@ static int notify_on_release(const struct cgroup *cgrp) } /** + * for_each_css - iterate all css's of a cgroup + * @css: the iteration cursor + * @ssid: the index of the subsystem, CGROUP_SUBSYS_COUNT after reaching the end + * @cgrp: the target cgroup to iterate css's of + * + * Should be called under cgroup_mutex. + */ +#define for_each_css(css, ssid, cgrp) \ + for ((ssid) = 0; (ssid) < CGROUP_SUBSYS_COUNT; (ssid)++) \ + if (!((css) = rcu_dereference_check( \ + (cgrp)->subsys[(ssid)], \ + lockdep_is_held(&cgroup_mutex)))) { } \ + else + +/** * for_each_subsys - iterate all loaded cgroup subsystems * @ss: the iteration cursor - * @i: the index of @ss, CGROUP_SUBSYS_COUNT after reaching the end + * @ssid: the index of @ss, CGROUP_SUBSYS_COUNT after reaching the end * - * Should be called under cgroup_mutex. + * Iterates through all loaded subsystems. Should be called under + * cgroup_mutex or cgroup_root_mutex. */ -#define for_each_subsys(ss, i) \ - for ((i) = 0; (i) < CGROUP_SUBSYS_COUNT; (i)++) \ - if (({ lockdep_assert_held(&cgroup_mutex); \ - !((ss) = cgroup_subsys[i]); })) { } \ +#define for_each_subsys(ss, ssid) \ + for (({ cgroup_assert_mutex_or_root_locked(); (ssid) = 0; }); \ + (ssid) < CGROUP_SUBSYS_COUNT; (ssid)++) \ + if (!((ss) = cgroup_subsys[(ssid)])) { } \ else /** @@ -286,10 +283,6 @@ static int notify_on_release(const struct cgroup *cgrp) for ((i) = 0; (i) < CGROUP_BUILTIN_SUBSYS_COUNT && \ (((ss) = cgroup_subsys[i]) || true); (i)++) -/* iterate each subsystem attached to a hierarchy */ -#define for_each_root_subsys(root, ss) \ - list_for_each_entry((ss), &(root)->subsys_list, sibling) - /* iterate across the active hierarchies */ #define for_each_active_root(root) \ list_for_each_entry((root), &cgroup_roots, root_list) @@ -863,11 +856,7 @@ static void cgroup_free_fn(struct work_struct *work) */ deactivate_super(cgrp->root->sb); - /* - * if we're getting rid of the cgroup, refcount should ensure - * that there are no pidlists left. - */ - BUG_ON(!list_empty(&cgrp->pidlists)); + cgroup_pidlist_destroy_all(cgrp); simple_xattrs_free(&cgrp->xattrs); @@ -1050,7 +1039,6 @@ static int rebind_subsystems(struct cgroupfs_root *root, cgroup_css(cgroup_dummy_top, ss)); cgroup_css(cgrp, ss)->cgroup = cgrp; - list_move(&ss->sibling, &root->subsys_list); ss->root = root; if (ss->bind) ss->bind(cgroup_css(cgrp, ss)); @@ -1069,7 +1057,6 @@ static int rebind_subsystems(struct cgroupfs_root *root, RCU_INIT_POINTER(cgrp->subsys[i], NULL); cgroup_subsys[i]->root = &cgroup_dummy_root; - list_move(&ss->sibling, &cgroup_dummy_root.subsys_list); /* subsystem is now free - drop reference on module */ module_put(ss->module); @@ -1096,10 +1083,12 @@ static int cgroup_show_options(struct seq_file *seq, struct dentry *dentry) { struct cgroupfs_root *root = dentry->d_sb->s_fs_info; struct cgroup_subsys *ss; + int ssid; mutex_lock(&cgroup_root_mutex); - for_each_root_subsys(root, ss) - seq_printf(seq, ",%s", ss->name); + for_each_subsys(ss, ssid) + if (root->subsys_mask & (1 << ssid)) + seq_printf(seq, ",%s", ss->name); if (root->flags & CGRP_ROOT_SANE_BEHAVIOR) seq_puts(seq, ",sane_behavior"); if (root->flags & CGRP_ROOT_NOPREFIX) @@ -1362,8 +1351,6 @@ static void init_cgroup_housekeeping(struct cgroup *cgrp) INIT_LIST_HEAD(&cgrp->pidlists); mutex_init(&cgrp->pidlist_mutex); cgrp->dummy_css.cgroup = cgrp; - INIT_LIST_HEAD(&cgrp->event_list); - spin_lock_init(&cgrp->event_list_lock); simple_xattrs_init(&cgrp->xattrs); } @@ -1371,7 +1358,6 @@ static void init_cgroup_root(struct cgroupfs_root *root) { struct cgroup *cgrp = &root->top_cgroup; - INIT_LIST_HEAD(&root->subsys_list); INIT_LIST_HEAD(&root->root_list); root->number_of_cgroups = 1; cgrp->root = root; @@ -1693,7 +1679,8 @@ static struct dentry *cgroup_mount(struct file_system_type *fs_type, return ERR_PTR(ret); } -static void cgroup_kill_sb(struct super_block *sb) { +static void cgroup_kill_sb(struct super_block *sb) +{ struct cgroupfs_root *root = sb->s_fs_info; struct cgroup *cgrp = &root->top_cgroup; struct cgrp_cset_link *link, *tmp_link; @@ -1976,8 +1963,8 @@ static int cgroup_attach_task(struct cgroup *cgrp, struct task_struct *tsk, bool threadgroup) { int retval, i, group_size; - struct cgroup_subsys *ss, *failed_ss = NULL; struct cgroupfs_root *root = cgrp->root; + struct cgroup_subsys_state *css, *failed_css = NULL; /* threadgroup list cursor and array */ struct task_struct *leader = tsk; struct task_and_cgroup *tc; @@ -2050,13 +2037,11 @@ static int cgroup_attach_task(struct cgroup *cgrp, struct task_struct *tsk, /* * step 1: check that we can legitimately attach to the cgroup. */ - for_each_root_subsys(root, ss) { - struct cgroup_subsys_state *css = cgroup_css(cgrp, ss); - - if (ss->can_attach) { - retval = ss->can_attach(css, &tset); + for_each_css(css, i, cgrp) { + if (css->ss->can_attach) { + retval = css->ss->can_attach(css, &tset); if (retval) { - failed_ss = ss; + failed_css = css; goto out_cancel_attach; } } @@ -2092,12 +2077,9 @@ static int cgroup_attach_task(struct cgroup *cgrp, struct task_struct *tsk, /* * step 4: do subsystem attach callbacks. */ - for_each_root_subsys(root, ss) { - struct cgroup_subsys_state *css = cgroup_css(cgrp, ss); - - if (ss->attach) - ss->attach(css, &tset); - } + for_each_css(css, i, cgrp) + if (css->ss->attach) + css->ss->attach(css, &tset); /* * step 5: success! and cleanup @@ -2114,13 +2096,11 @@ out_put_css_set_refs: } out_cancel_attach: if (retval) { - for_each_root_subsys(root, ss) { - struct cgroup_subsys_state *css = cgroup_css(cgrp, ss); - - if (ss == failed_ss) + for_each_css(css, i, cgrp) { + if (css == failed_css) break; - if (ss->cancel_attach) - ss->cancel_attach(css, &tset); + if (css->ss->cancel_attach) + css->ss->cancel_attach(css, &tset); } } out_free_group_list: @@ -2148,7 +2128,7 @@ retry_find_task: tsk = find_task_by_vpid(pid); if (!tsk) { rcu_read_unlock(); - ret= -ESRCH; + ret = -ESRCH; goto out_unlock_cgroup; } /* @@ -2260,10 +2240,9 @@ static int cgroup_release_agent_write(struct cgroup_subsys_state *css, return 0; } -static int cgroup_release_agent_show(struct cgroup_subsys_state *css, - struct cftype *cft, struct seq_file *seq) +static int cgroup_release_agent_show(struct seq_file *seq, void *v) { - struct cgroup *cgrp = css->cgroup; + struct cgroup *cgrp = seq_css(seq)->cgroup; if (!cgroup_lock_live_group(cgrp)) return -ENODEV; @@ -2273,174 +2252,129 @@ static int cgroup_release_agent_show(struct cgroup_subsys_state *css, return 0; } -static int cgroup_sane_behavior_show(struct cgroup_subsys_state *css, - struct cftype *cft, struct seq_file *seq) +static int cgroup_sane_behavior_show(struct seq_file *seq, void *v) { - seq_printf(seq, "%d\n", cgroup_sane_behavior(css->cgroup)); + struct cgroup *cgrp = seq_css(seq)->cgroup; + + seq_printf(seq, "%d\n", cgroup_sane_behavior(cgrp)); return 0; } /* A buffer size big enough for numbers or short strings */ #define CGROUP_LOCAL_BUFFER_SIZE 64 -static ssize_t cgroup_write_X64(struct cgroup_subsys_state *css, - struct cftype *cft, struct file *file, - const char __user *userbuf, size_t nbytes, - loff_t *unused_ppos) +static ssize_t cgroup_file_write(struct file *file, const char __user *userbuf, + size_t nbytes, loff_t *ppos) { - char buffer[CGROUP_LOCAL_BUFFER_SIZE]; - int retval = 0; - char *end; + struct cfent *cfe = __d_cfe(file->f_dentry); + struct cftype *cft = __d_cft(file->f_dentry); + struct cgroup_subsys_state *css = cfe->css; + size_t max_bytes = cft->max_write_len ?: CGROUP_LOCAL_BUFFER_SIZE - 1; + char *buf; + int ret; - if (!nbytes) - return -EINVAL; - if (nbytes >= sizeof(buffer)) + if (nbytes >= max_bytes) return -E2BIG; - if (copy_from_user(buffer, userbuf, nbytes)) - return -EFAULT; - buffer[nbytes] = 0; /* nul-terminate */ - if (cft->write_u64) { - u64 val = simple_strtoull(strstrip(buffer), &end, 0); - if (*end) - return -EINVAL; - retval = cft->write_u64(css, cft, val); + buf = kmalloc(nbytes + 1, GFP_KERNEL); + if (!buf) + return -ENOMEM; + + if (copy_from_user(buf, userbuf, nbytes)) { + ret = -EFAULT; + goto out_free; + } + + buf[nbytes] = '\0'; + + if (cft->write_string) { + ret = cft->write_string(css, cft, strstrip(buf)); + } else if (cft->write_u64) { + unsigned long long v; + ret = kstrtoull(buf, 0, &v); + if (!ret) + ret = cft->write_u64(css, cft, v); + } else if (cft->write_s64) { + long long v; + ret = kstrtoll(buf, 0, &v); + if (!ret) + ret = cft->write_s64(css, cft, v); + } else if (cft->trigger) { + ret = cft->trigger(css, (unsigned int)cft->private); } else { - s64 val = simple_strtoll(strstrip(buffer), &end, 0); - if (*end) - return -EINVAL; - retval = cft->write_s64(css, cft, val); + ret = -EINVAL; } - if (!retval) - retval = nbytes; - return retval; +out_free: + kfree(buf); + return ret ?: nbytes; } -static ssize_t cgroup_write_string(struct cgroup_subsys_state *css, - struct cftype *cft, struct file *file, - const char __user *userbuf, size_t nbytes, - loff_t *unused_ppos) +/* + * seqfile ops/methods for returning structured data. Currently just + * supports string->u64 maps, but can be extended in future. + */ + +static void *cgroup_seqfile_start(struct seq_file *seq, loff_t *ppos) { - char local_buffer[CGROUP_LOCAL_BUFFER_SIZE]; - int retval = 0; - size_t max_bytes = cft->max_write_len; - char *buffer = local_buffer; + struct cftype *cft = seq_cft(seq); - if (!max_bytes) - max_bytes = sizeof(local_buffer) - 1; - if (nbytes >= max_bytes) - return -E2BIG; - /* Allocate a dynamic buffer if we need one */ - if (nbytes >= sizeof(local_buffer)) { - buffer = kmalloc(nbytes + 1, GFP_KERNEL); - if (buffer == NULL) - return -ENOMEM; - } - if (nbytes && copy_from_user(buffer, userbuf, nbytes)) { - retval = -EFAULT; - goto out; + if (cft->seq_start) { + return cft->seq_start(seq, ppos); + } else { + /* + * The same behavior and code as single_open(). Returns + * !NULL if pos is at the beginning; otherwise, NULL. + */ + return NULL + !*ppos; } - - buffer[nbytes] = 0; /* nul-terminate */ - retval = cft->write_string(css, cft, strstrip(buffer)); - if (!retval) - retval = nbytes; -out: - if (buffer != local_buffer) - kfree(buffer); - return retval; } -static ssize_t cgroup_file_write(struct file *file, const char __user *buf, - size_t nbytes, loff_t *ppos) +static void *cgroup_seqfile_next(struct seq_file *seq, void *v, loff_t *ppos) { - struct cfent *cfe = __d_cfe(file->f_dentry); - struct cftype *cft = __d_cft(file->f_dentry); - struct cgroup_subsys_state *css = cfe->css; + struct cftype *cft = seq_cft(seq); - if (cft->write) - return cft->write(css, cft, file, buf, nbytes, ppos); - if (cft->write_u64 || cft->write_s64) - return cgroup_write_X64(css, cft, file, buf, nbytes, ppos); - if (cft->write_string) - return cgroup_write_string(css, cft, file, buf, nbytes, ppos); - if (cft->trigger) { - int ret = cft->trigger(css, (unsigned int)cft->private); - return ret ? ret : nbytes; + if (cft->seq_next) { + return cft->seq_next(seq, v, ppos); + } else { + /* + * The same behavior and code as single_open(), always + * terminate after the initial read. + */ + ++*ppos; + return NULL; } - return -EINVAL; } -static ssize_t cgroup_read_u64(struct cgroup_subsys_state *css, - struct cftype *cft, struct file *file, - char __user *buf, size_t nbytes, loff_t *ppos) +static void cgroup_seqfile_stop(struct seq_file *seq, void *v) { - char tmp[CGROUP_LOCAL_BUFFER_SIZE]; - u64 val = cft->read_u64(css, cft); - int len = sprintf(tmp, "%llu\n", (unsigned long long) val); + struct cftype *cft = seq_cft(seq); - return simple_read_from_buffer(buf, nbytes, ppos, tmp, len); + if (cft->seq_stop) + cft->seq_stop(seq, v); } -static ssize_t cgroup_read_s64(struct cgroup_subsys_state *css, - struct cftype *cft, struct file *file, - char __user *buf, size_t nbytes, loff_t *ppos) +static int cgroup_seqfile_show(struct seq_file *m, void *arg) { - char tmp[CGROUP_LOCAL_BUFFER_SIZE]; - s64 val = cft->read_s64(css, cft); - int len = sprintf(tmp, "%lld\n", (long long) val); + struct cftype *cft = seq_cft(m); + struct cgroup_subsys_state *css = seq_css(m); - return simple_read_from_buffer(buf, nbytes, ppos, tmp, len); -} + if (cft->seq_show) + return cft->seq_show(m, arg); -static ssize_t cgroup_file_read(struct file *file, char __user *buf, - size_t nbytes, loff_t *ppos) -{ - struct cfent *cfe = __d_cfe(file->f_dentry); - struct cftype *cft = __d_cft(file->f_dentry); - struct cgroup_subsys_state *css = cfe->css; - - if (cft->read) - return cft->read(css, cft, file, buf, nbytes, ppos); if (cft->read_u64) - return cgroup_read_u64(css, cft, file, buf, nbytes, ppos); - if (cft->read_s64) - return cgroup_read_s64(css, cft, file, buf, nbytes, ppos); - return -EINVAL; -} - -/* - * seqfile ops/methods for returning structured data. Currently just - * supports string->u64 maps, but can be extended in future. - */ - -static int cgroup_map_add(struct cgroup_map_cb *cb, const char *key, u64 value) -{ - struct seq_file *sf = cb->state; - return seq_printf(sf, "%s %llu\n", key, (unsigned long long)value); -} - -static int cgroup_seqfile_show(struct seq_file *m, void *arg) -{ - struct cfent *cfe = m->private; - struct cftype *cft = cfe->type; - struct cgroup_subsys_state *css = cfe->css; - - if (cft->read_map) { - struct cgroup_map_cb cb = { - .fill = cgroup_map_add, - .state = m, - }; - return cft->read_map(css, cft, &cb); - } - return cft->read_seq_string(css, cft, m); + seq_printf(m, "%llu\n", cft->read_u64(css, cft)); + else if (cft->read_s64) + seq_printf(m, "%lld\n", cft->read_s64(css, cft)); + else + return -EINVAL; + return 0; } -static const struct file_operations cgroup_seqfile_operations = { - .read = seq_read, - .write = cgroup_file_write, - .llseek = seq_lseek, - .release = cgroup_file_release, +static struct seq_operations cgroup_seq_operations = { + .start = cgroup_seqfile_start, + .next = cgroup_seqfile_next, + .stop = cgroup_seqfile_stop, + .show = cgroup_seqfile_show, }; static int cgroup_file_open(struct inode *inode, struct file *file) @@ -2449,6 +2383,7 @@ static int cgroup_file_open(struct inode *inode, struct file *file) struct cftype *cft = __d_cft(file->f_dentry); struct cgroup *cgrp = __d_cgrp(cfe->dentry->d_parent); struct cgroup_subsys_state *css; + struct cgroup_open_file *of; int err; err = generic_file_open(inode, file); @@ -2478,32 +2413,26 @@ static int cgroup_file_open(struct inode *inode, struct file *file) WARN_ON_ONCE(cfe->css && cfe->css != css); cfe->css = css; - if (cft->read_map || cft->read_seq_string) { - file->f_op = &cgroup_seqfile_operations; - err = single_open(file, cgroup_seqfile_show, cfe); - } else if (cft->open) { - err = cft->open(inode, file); + of = __seq_open_private(file, &cgroup_seq_operations, + sizeof(struct cgroup_open_file)); + if (of) { + of->cfe = cfe; + return 0; } - if (css->ss && err) + if (css->ss) css_put(css); - return err; + return -ENOMEM; } static int cgroup_file_release(struct inode *inode, struct file *file) { struct cfent *cfe = __d_cfe(file->f_dentry); - struct cftype *cft = __d_cft(file->f_dentry); struct cgroup_subsys_state *css = cfe->css; - int ret = 0; - if (cft->release) - ret = cft->release(inode, file); if (css->ss) css_put(css); - if (file->f_op == &cgroup_seqfile_operations) - single_release(inode, file); - return ret; + return seq_release_private(inode, file); } /* @@ -2614,7 +2543,7 @@ static ssize_t cgroup_listxattr(struct dentry *dentry, char *buf, size_t size) } static const struct file_operations cgroup_file_operations = { - .read = cgroup_file_read, + .read = seq_read, .write = cgroup_file_write, .llseek = generic_file_llseek, .open = cgroup_file_open, @@ -2639,16 +2568,6 @@ static const struct inode_operations cgroup_dir_inode_operations = { .removexattr = cgroup_removexattr, }; -/* - * Check if a file is a control file - */ -static inline struct cftype *__file_cft(struct file *file) -{ - if (file_inode(file)->i_fop != &cgroup_file_operations) - return ERR_PTR(-EINVAL); - return __d_cft(file->f_dentry); -} - static int cgroup_create_file(struct dentry *dentry, umode_t mode, struct super_block *sb) { @@ -2706,12 +2625,11 @@ static umode_t cgroup_file_mode(const struct cftype *cft) if (cft->mode) return cft->mode; - if (cft->read || cft->read_u64 || cft->read_s64 || - cft->read_map || cft->read_seq_string) + if (cft->read_u64 || cft->read_s64 || cft->seq_show) mode |= S_IRUGO; - if (cft->write || cft->write_u64 || cft->write_s64 || - cft->write_string || cft->trigger) + if (cft->write_u64 || cft->write_s64 || cft->write_string || + cft->trigger) mode |= S_IWUSR; return mode; @@ -3007,9 +2925,9 @@ static void cgroup_enable_task_cg_lists(void) * @parent_css: css whose children to walk * * This function returns the next child of @parent_css and should be called - * under RCU read lock. The only requirement is that @parent_css and - * @pos_css are accessible. The next sibling is guaranteed to be returned - * regardless of their states. + * under either cgroup_mutex or RCU read lock. The only requirement is + * that @parent_css and @pos_css are accessible. The next sibling is + * guaranteed to be returned regardless of their states. */ struct cgroup_subsys_state * css_next_child(struct cgroup_subsys_state *pos_css, @@ -3019,7 +2937,7 @@ css_next_child(struct cgroup_subsys_state *pos_css, struct cgroup *cgrp = parent_css->cgroup; struct cgroup *next; - WARN_ON_ONCE(!rcu_read_lock_held()); + cgroup_assert_mutex_or_rcu_locked(); /* * @pos could already have been removed. Once a cgroup is removed, @@ -3066,10 +2984,10 @@ EXPORT_SYMBOL_GPL(css_next_child); * to visit for pre-order traversal of @root's descendants. @root is * included in the iteration and the first node to be visited. * - * While this function requires RCU read locking, it doesn't require the - * whole traversal to be contained in a single RCU critical section. This - * function will return the correct next descendant as long as both @pos - * and @root are accessible and @pos is a descendant of @root. + * While this function requires cgroup_mutex or RCU read locking, it + * doesn't require the whole traversal to be contained in a single critical + * section. This function will return the correct next descendant as long + * as both @pos and @root are accessible and @pos is a descendant of @root. */ struct cgroup_subsys_state * css_next_descendant_pre(struct cgroup_subsys_state *pos, @@ -3077,7 +2995,7 @@ css_next_descendant_pre(struct cgroup_subsys_state *pos, { struct cgroup_subsys_state *next; - WARN_ON_ONCE(!rcu_read_lock_held()); + cgroup_assert_mutex_or_rcu_locked(); /* if first iteration, visit @root */ if (!pos) @@ -3108,17 +3026,17 @@ EXPORT_SYMBOL_GPL(css_next_descendant_pre); * is returned. This can be used during pre-order traversal to skip * subtree of @pos. * - * While this function requires RCU read locking, it doesn't require the - * whole traversal to be contained in a single RCU critical section. This - * function will return the correct rightmost descendant as long as @pos is - * accessible. + * While this function requires cgroup_mutex or RCU read locking, it + * doesn't require the whole traversal to be contained in a single critical + * section. This function will return the correct rightmost descendant as + * long as @pos is accessible. */ struct cgroup_subsys_state * css_rightmost_descendant(struct cgroup_subsys_state *pos) { struct cgroup_subsys_state *last, *tmp; - WARN_ON_ONCE(!rcu_read_lock_held()); + cgroup_assert_mutex_or_rcu_locked(); do { last = pos; @@ -3154,10 +3072,11 @@ css_leftmost_descendant(struct cgroup_subsys_state *pos) * to visit for post-order traversal of @root's descendants. @root is * included in the iteration and the last node to be visited. * - * While this function requires RCU read locking, it doesn't require the - * whole traversal to be contained in a single RCU critical section. This - * function will return the correct next descendant as long as both @pos - * and @cgroup are accessible and @pos is a descendant of @cgroup. + * While this function requires cgroup_mutex or RCU read locking, it + * doesn't require the whole traversal to be contained in a single critical + * section. This function will return the correct next descendant as long + * as both @pos and @cgroup are accessible and @pos is a descendant of + * @cgroup. */ struct cgroup_subsys_state * css_next_descendant_post(struct cgroup_subsys_state *pos, @@ -3165,7 +3084,7 @@ css_next_descendant_post(struct cgroup_subsys_state *pos, { struct cgroup_subsys_state *next; - WARN_ON_ONCE(!rcu_read_lock_held()); + cgroup_assert_mutex_or_rcu_locked(); /* if first iteration, visit leftmost descendant which may be @root */ if (!pos) @@ -3504,14 +3423,12 @@ struct cgroup_pidlist { pid_t *list; /* how many elements the above list has */ int length; - /* how many files are using the current array */ - int use_count; /* each of these stored in a list by its cgroup */ struct list_head links; /* pointer to the cgroup we belong to, for list removal purposes */ struct cgroup *owner; - /* protects the other fields */ - struct rw_semaphore rwsem; + /* for delayed destruction */ + struct delayed_work destroy_dwork; }; /* @@ -3527,6 +3444,7 @@ static void *pidlist_allocate(int count) else return kmalloc(count * sizeof(pid_t), GFP_KERNEL); } + static void pidlist_free(void *p) { if (is_vmalloc_addr(p)) @@ -3536,6 +3454,47 @@ static void pidlist_free(void *p) } /* + * Used to destroy all pidlists lingering waiting for destroy timer. None + * should be left afterwards. + */ +static void cgroup_pidlist_destroy_all(struct cgroup *cgrp) +{ + struct cgroup_pidlist *l, *tmp_l; + + mutex_lock(&cgrp->pidlist_mutex); + list_for_each_entry_safe(l, tmp_l, &cgrp->pidlists, links) + mod_delayed_work(cgroup_pidlist_destroy_wq, &l->destroy_dwork, 0); + mutex_unlock(&cgrp->pidlist_mutex); + + flush_workqueue(cgroup_pidlist_destroy_wq); + BUG_ON(!list_empty(&cgrp->pidlists)); +} + +static void cgroup_pidlist_destroy_work_fn(struct work_struct *work) +{ + struct delayed_work *dwork = to_delayed_work(work); + struct cgroup_pidlist *l = container_of(dwork, struct cgroup_pidlist, + destroy_dwork); + struct cgroup_pidlist *tofree = NULL; + + mutex_lock(&l->owner->pidlist_mutex); + + /* + * Destroy iff we didn't get queued again. The state won't change + * as destroy_dwork can only be queued while locked. + */ + if (!delayed_work_pending(dwork)) { + list_del(&l->links); + pidlist_free(l->list); + put_pid_ns(l->key.ns); + tofree = l; + } + + mutex_unlock(&l->owner->pidlist_mutex); + kfree(tofree); +} + +/* * pidlist_uniq - given a kmalloc()ed list, strip out all duplicate entries * Returns the number of unique elements. */ @@ -3565,52 +3524,92 @@ after: return dest; } +/* + * The two pid files - task and cgroup.procs - guaranteed that the result + * is sorted, which forced this whole pidlist fiasco. As pid order is + * different per namespace, each namespace needs differently sorted list, + * making it impossible to use, for example, single rbtree of member tasks + * sorted by task pointer. As pidlists can be fairly large, allocating one + * per open file is dangerous, so cgroup had to implement shared pool of + * pidlists keyed by cgroup and namespace. + * + * All this extra complexity was caused by the original implementation + * committing to an entirely unnecessary property. In the long term, we + * want to do away with it. Explicitly scramble sort order if + * sane_behavior so that no such expectation exists in the new interface. + * + * Scrambling is done by swapping every two consecutive bits, which is + * non-identity one-to-one mapping which disturbs sort order sufficiently. + */ +static pid_t pid_fry(pid_t pid) +{ + unsigned a = pid & 0x55555555; + unsigned b = pid & 0xAAAAAAAA; + + return (a << 1) | (b >> 1); +} + +static pid_t cgroup_pid_fry(struct cgroup *cgrp, pid_t pid) +{ + if (cgroup_sane_behavior(cgrp)) + return pid_fry(pid); + else + return pid; +} + static int cmppid(const void *a, const void *b) { return *(pid_t *)a - *(pid_t *)b; } +static int fried_cmppid(const void *a, const void *b) +{ + return pid_fry(*(pid_t *)a) - pid_fry(*(pid_t *)b); +} + +static struct cgroup_pidlist *cgroup_pidlist_find(struct cgroup *cgrp, + enum cgroup_filetype type) +{ + struct cgroup_pidlist *l; + /* don't need task_nsproxy() if we're looking at ourself */ + struct pid_namespace *ns = task_active_pid_ns(current); + + lockdep_assert_held(&cgrp->pidlist_mutex); + + list_for_each_entry(l, &cgrp->pidlists, links) + if (l->key.type == type && l->key.ns == ns) + return l; + return NULL; +} + /* * find the appropriate pidlist for our purpose (given procs vs tasks) * returns with the lock on that pidlist already held, and takes care * of the use count, or returns NULL with no locks held if we're out of * memory. */ -static struct cgroup_pidlist *cgroup_pidlist_find(struct cgroup *cgrp, - enum cgroup_filetype type) +static struct cgroup_pidlist *cgroup_pidlist_find_create(struct cgroup *cgrp, + enum cgroup_filetype type) { struct cgroup_pidlist *l; - /* don't need task_nsproxy() if we're looking at ourself */ - struct pid_namespace *ns = task_active_pid_ns(current); - /* - * We can't drop the pidlist_mutex before taking the l->rwsem in case - * the last ref-holder is trying to remove l from the list at the same - * time. Holding the pidlist_mutex precludes somebody taking whichever - * list we find out from under us - compare release_pid_array(). - */ - mutex_lock(&cgrp->pidlist_mutex); - list_for_each_entry(l, &cgrp->pidlists, links) { - if (l->key.type == type && l->key.ns == ns) { - /* make sure l doesn't vanish out from under us */ - down_write(&l->rwsem); - mutex_unlock(&cgrp->pidlist_mutex); - return l; - } - } + lockdep_assert_held(&cgrp->pidlist_mutex); + + l = cgroup_pidlist_find(cgrp, type); + if (l) + return l; + /* entry not found; create a new one */ l = kzalloc(sizeof(struct cgroup_pidlist), GFP_KERNEL); - if (!l) { - mutex_unlock(&cgrp->pidlist_mutex); + if (!l) return l; - } - init_rwsem(&l->rwsem); - down_write(&l->rwsem); + + INIT_DELAYED_WORK(&l->destroy_dwork, cgroup_pidlist_destroy_work_fn); l->key.type = type; - l->key.ns = get_pid_ns(ns); + /* don't need task_nsproxy() if we're looking at ourself */ + l->key.ns = get_pid_ns(task_active_pid_ns(current)); l->owner = cgrp; list_add(&l->links, &cgrp->pidlists); - mutex_unlock(&cgrp->pidlist_mutex); return l; } @@ -3627,6 +3626,8 @@ static int pidlist_array_load(struct cgroup *cgrp, enum cgroup_filetype type, struct task_struct *tsk; struct cgroup_pidlist *l; + lockdep_assert_held(&cgrp->pidlist_mutex); + /* * If cgroup gets more users after we read count, we won't have * enough space - tough. This race is indistinguishable to the @@ -3653,20 +3654,24 @@ static int pidlist_array_load(struct cgroup *cgrp, enum cgroup_filetype type, css_task_iter_end(&it); length = n; /* now sort & (if procs) strip out duplicates */ - sort(array, length, sizeof(pid_t), cmppid, NULL); + if (cgroup_sane_behavior(cgrp)) + sort(array, length, sizeof(pid_t), fried_cmppid, NULL); + else + sort(array, length, sizeof(pid_t), cmppid, NULL); if (type == CGROUP_FILE_PROCS) length = pidlist_uniq(array, length); - l = cgroup_pidlist_find(cgrp, type); + + l = cgroup_pidlist_find_create(cgrp, type); if (!l) { + mutex_unlock(&cgrp->pidlist_mutex); pidlist_free(array); return -ENOMEM; } - /* store array, freeing old if necessary - lock already held */ + + /* store array, freeing old if necessary */ pidlist_free(l->list); l->list = array; l->length = length; - l->use_count++; - up_write(&l->rwsem); *lp = l; return 0; } @@ -3740,20 +3745,45 @@ static void *cgroup_pidlist_start(struct seq_file *s, loff_t *pos) * after a seek to the start). Use a binary-search to find the * next pid to display, if any */ - struct cgroup_pidlist *l = s->private; + struct cgroup_open_file *of = s->private; + struct cgroup *cgrp = seq_css(s)->cgroup; + struct cgroup_pidlist *l; + enum cgroup_filetype type = seq_cft(s)->private; int index = 0, pid = *pos; - int *iter; + int *iter, ret; + + mutex_lock(&cgrp->pidlist_mutex); + + /* + * !NULL @of->priv indicates that this isn't the first start() + * after open. If the matching pidlist is around, we can use that. + * Look for it. Note that @of->priv can't be used directly. It + * could already have been destroyed. + */ + if (of->priv) + of->priv = cgroup_pidlist_find(cgrp, type); + + /* + * Either this is the first start() after open or the matching + * pidlist has been destroyed inbetween. Create a new one. + */ + if (!of->priv) { + ret = pidlist_array_load(cgrp, type, + (struct cgroup_pidlist **)&of->priv); + if (ret) + return ERR_PTR(ret); + } + l = of->priv; - down_read(&l->rwsem); if (pid) { int end = l->length; while (index < end) { int mid = (index + end) / 2; - if (l->list[mid] == pid) { + if (cgroup_pid_fry(cgrp, l->list[mid]) == pid) { index = mid; break; - } else if (l->list[mid] <= pid) + } else if (cgroup_pid_fry(cgrp, l->list[mid]) <= pid) index = mid + 1; else end = mid; @@ -3764,19 +3794,25 @@ static void *cgroup_pidlist_start(struct seq_file *s, loff_t *pos) return NULL; /* Update the abstract position to be the actual pid that we found */ iter = l->list + index; - *pos = *iter; + *pos = cgroup_pid_fry(cgrp, *iter); return iter; } static void cgroup_pidlist_stop(struct seq_file *s, void *v) { - struct cgroup_pidlist *l = s->private; - up_read(&l->rwsem); + struct cgroup_open_file *of = s->private; + struct cgroup_pidlist *l = of->priv; + + if (l) + mod_delayed_work(cgroup_pidlist_destroy_wq, &l->destroy_dwork, + CGROUP_PIDLIST_DESTROY_DELAY); + mutex_unlock(&seq_css(s)->cgroup->pidlist_mutex); } static void *cgroup_pidlist_next(struct seq_file *s, void *v, loff_t *pos) { - struct cgroup_pidlist *l = s->private; + struct cgroup_open_file *of = s->private; + struct cgroup_pidlist *l = of->priv; pid_t *p = v; pid_t *end = l->list + l->length; /* @@ -3787,7 +3823,7 @@ static void *cgroup_pidlist_next(struct seq_file *s, void *v, loff_t *pos) if (p >= end) { return NULL; } else { - *pos = *p; + *pos = cgroup_pid_fry(seq_css(s)->cgroup, *p); return p; } } @@ -3808,92 +3844,6 @@ static const struct seq_operations cgroup_pidlist_seq_operations = { .show = cgroup_pidlist_show, }; -static void cgroup_release_pid_array(struct cgroup_pidlist *l) -{ - /* - * the case where we're the last user of this particular pidlist will - * have us remove it from the cgroup's list, which entails taking the - * mutex. since in pidlist_find the pidlist->lock depends on cgroup-> - * pidlist_mutex, we have to take pidlist_mutex first. - */ - mutex_lock(&l->owner->pidlist_mutex); - down_write(&l->rwsem); - BUG_ON(!l->use_count); - if (!--l->use_count) { - /* we're the last user if refcount is 0; remove and free */ - list_del(&l->links); - mutex_unlock(&l->owner->pidlist_mutex); - pidlist_free(l->list); - put_pid_ns(l->key.ns); - up_write(&l->rwsem); - kfree(l); - return; - } - mutex_unlock(&l->owner->pidlist_mutex); - up_write(&l->rwsem); -} - -static int cgroup_pidlist_release(struct inode *inode, struct file *file) -{ - struct cgroup_pidlist *l; - if (!(file->f_mode & FMODE_READ)) - return 0; - /* - * the seq_file will only be initialized if the file was opened for - * reading; hence we check if it's not null only in that case. - */ - l = ((struct seq_file *)file->private_data)->private; - cgroup_release_pid_array(l); - return seq_release(inode, file); -} - -static const struct file_operations cgroup_pidlist_operations = { - .read = seq_read, - .llseek = seq_lseek, - .write = cgroup_file_write, - .release = cgroup_pidlist_release, -}; - -/* - * The following functions handle opens on a file that displays a pidlist - * (tasks or procs). Prepare an array of the process/thread IDs of whoever's - * in the cgroup. - */ -/* helper function for the two below it */ -static int cgroup_pidlist_open(struct file *file, enum cgroup_filetype type) -{ - struct cgroup *cgrp = __d_cgrp(file->f_dentry->d_parent); - struct cgroup_pidlist *l; - int retval; - - /* Nothing to do for write-only files */ - if (!(file->f_mode & FMODE_READ)) - return 0; - - /* have the array populated */ - retval = pidlist_array_load(cgrp, type, &l); - if (retval) - return retval; - /* configure file information */ - file->f_op = &cgroup_pidlist_operations; - - retval = seq_open(file, &cgroup_pidlist_seq_operations); - if (retval) { - cgroup_release_pid_array(l); - return retval; - } - ((struct seq_file *)file->private_data)->private = l; - return 0; -} -static int cgroup_tasks_open(struct inode *unused, struct file *file) -{ - return cgroup_pidlist_open(file, CGROUP_FILE_TASKS); -} -static int cgroup_procs_open(struct inode *unused, struct file *file) -{ - return cgroup_pidlist_open(file, CGROUP_FILE_PROCS); -} - static u64 cgroup_read_notify_on_release(struct cgroup_subsys_state *css, struct cftype *cft) { @@ -3928,202 +3878,6 @@ static void cgroup_dput(struct cgroup *cgrp) deactivate_super(sb); } -/* - * Unregister event and free resources. - * - * Gets called from workqueue. - */ -static void cgroup_event_remove(struct work_struct *work) -{ - struct cgroup_event *event = container_of(work, struct cgroup_event, - remove); - struct cgroup_subsys_state *css = event->css; - - remove_wait_queue(event->wqh, &event->wait); - - event->cft->unregister_event(css, event->cft, event->eventfd); - - /* Notify userspace the event is going away. */ - eventfd_signal(event->eventfd, 1); - - eventfd_ctx_put(event->eventfd); - kfree(event); - css_put(css); -} - -/* - * Gets called on POLLHUP on eventfd when user closes it. - * - * Called with wqh->lock held and interrupts disabled. - */ -static int cgroup_event_wake(wait_queue_t *wait, unsigned mode, - int sync, void *key) -{ - struct cgroup_event *event = container_of(wait, - struct cgroup_event, wait); - struct cgroup *cgrp = event->css->cgroup; - unsigned long flags = (unsigned long)key; - - if (flags & POLLHUP) { - /* - * If the event has been detached at cgroup removal, we - * can simply return knowing the other side will cleanup - * for us. - * - * We can't race against event freeing since the other - * side will require wqh->lock via remove_wait_queue(), - * which we hold. - */ - spin_lock(&cgrp->event_list_lock); - if (!list_empty(&event->list)) { - list_del_init(&event->list); - /* - * We are in atomic context, but cgroup_event_remove() - * may sleep, so we have to call it in workqueue. - */ - schedule_work(&event->remove); - } - spin_unlock(&cgrp->event_list_lock); - } - - return 0; -} - -static void cgroup_event_ptable_queue_proc(struct file *file, - wait_queue_head_t *wqh, poll_table *pt) -{ - struct cgroup_event *event = container_of(pt, - struct cgroup_event, pt); - - event->wqh = wqh; - add_wait_queue(wqh, &event->wait); -} - -/* - * Parse input and register new cgroup event handler. - * - * Input must be in format '<event_fd> <control_fd> <args>'. - * Interpretation of args is defined by control file implementation. - */ -static int cgroup_write_event_control(struct cgroup_subsys_state *dummy_css, - struct cftype *cft, const char *buffer) -{ - struct cgroup *cgrp = dummy_css->cgroup; - struct cgroup_event *event; - struct cgroup_subsys_state *cfile_css; - unsigned int efd, cfd; - struct fd efile; - struct fd cfile; - char *endp; - int ret; - - efd = simple_strtoul(buffer, &endp, 10); - if (*endp != ' ') - return -EINVAL; - buffer = endp + 1; - - cfd = simple_strtoul(buffer, &endp, 10); - if ((*endp != ' ') && (*endp != '\0')) - return -EINVAL; - buffer = endp + 1; - - event = kzalloc(sizeof(*event), GFP_KERNEL); - if (!event) - return -ENOMEM; - - INIT_LIST_HEAD(&event->list); - init_poll_funcptr(&event->pt, cgroup_event_ptable_queue_proc); - init_waitqueue_func_entry(&event->wait, cgroup_event_wake); - INIT_WORK(&event->remove, cgroup_event_remove); - - efile = fdget(efd); - if (!efile.file) { - ret = -EBADF; - goto out_kfree; - } - - event->eventfd = eventfd_ctx_fileget(efile.file); - if (IS_ERR(event->eventfd)) { - ret = PTR_ERR(event->eventfd); - goto out_put_efile; - } - - cfile = fdget(cfd); - if (!cfile.file) { - ret = -EBADF; - goto out_put_eventfd; - } - - /* the process need read permission on control file */ - /* AV: shouldn't we check that it's been opened for read instead? */ - ret = inode_permission(file_inode(cfile.file), MAY_READ); - if (ret < 0) - goto out_put_cfile; - - event->cft = __file_cft(cfile.file); - if (IS_ERR(event->cft)) { - ret = PTR_ERR(event->cft); - goto out_put_cfile; - } - - if (!event->cft->ss) { - ret = -EBADF; - goto out_put_cfile; - } - - /* - * Determine the css of @cfile, verify it belongs to the same - * cgroup as cgroup.event_control, and associate @event with it. - * Remaining events are automatically removed on cgroup destruction - * but the removal is asynchronous, so take an extra ref. - */ - rcu_read_lock(); - - ret = -EINVAL; - event->css = cgroup_css(cgrp, event->cft->ss); - cfile_css = css_from_dir(cfile.file->f_dentry->d_parent, event->cft->ss); - if (event->css && event->css == cfile_css && css_tryget(event->css)) - ret = 0; - - rcu_read_unlock(); - if (ret) - goto out_put_cfile; - - if (!event->cft->register_event || !event->cft->unregister_event) { - ret = -EINVAL; - goto out_put_css; - } - - ret = event->cft->register_event(event->css, event->cft, - event->eventfd, buffer); - if (ret) - goto out_put_css; - - efile.file->f_op->poll(efile.file, &event->pt); - - spin_lock(&cgrp->event_list_lock); - list_add(&event->list, &cgrp->event_list); - spin_unlock(&cgrp->event_list_lock); - - fdput(cfile); - fdput(efile); - - return 0; - -out_put_css: - css_put(event->css); -out_put_cfile: - fdput(cfile); -out_put_eventfd: - eventfd_ctx_put(event->eventfd); -out_put_efile: - fdput(efile); -out_kfree: - kfree(event); - - return ret; -} - static u64 cgroup_clone_children_read(struct cgroup_subsys_state *css, struct cftype *cft) { @@ -4143,17 +3897,15 @@ static int cgroup_clone_children_write(struct cgroup_subsys_state *css, static struct cftype cgroup_base_files[] = { { .name = "cgroup.procs", - .open = cgroup_procs_open, + .seq_start = cgroup_pidlist_start, + .seq_next = cgroup_pidlist_next, + .seq_stop = cgroup_pidlist_stop, + .seq_show = cgroup_pidlist_show, + .private = CGROUP_FILE_PROCS, .write_u64 = cgroup_procs_write, - .release = cgroup_pidlist_release, .mode = S_IRUGO | S_IWUSR, }, { - .name = "cgroup.event_control", - .write_string = cgroup_write_event_control, - .mode = S_IWUGO, - }, - { .name = "cgroup.clone_children", .flags = CFTYPE_INSANE, .read_u64 = cgroup_clone_children_read, @@ -4162,7 +3914,7 @@ static struct cftype cgroup_base_files[] = { { .name = "cgroup.sane_behavior", .flags = CFTYPE_ONLY_ON_ROOT, - .read_seq_string = cgroup_sane_behavior_show, + .seq_show = cgroup_sane_behavior_show, }, /* @@ -4173,9 +3925,12 @@ static struct cftype cgroup_base_files[] = { { .name = "tasks", .flags = CFTYPE_INSANE, /* use "procs" instead */ - .open = cgroup_tasks_open, + .seq_start = cgroup_pidlist_start, + .seq_next = cgroup_pidlist_next, + .seq_stop = cgroup_pidlist_stop, + .seq_show = cgroup_pidlist_show, + .private = CGROUP_FILE_TASKS, .write_u64 = cgroup_tasks_write, - .release = cgroup_pidlist_release, .mode = S_IRUGO | S_IWUSR, }, { @@ -4187,7 +3942,7 @@ static struct cftype cgroup_base_files[] = { { .name = "release_agent", .flags = CFTYPE_INSANE | CFTYPE_ONLY_ON_ROOT, - .read_seq_string = cgroup_release_agent_show, + .seq_show = cgroup_release_agent_show, .write_string = cgroup_release_agent_write, .max_write_len = PATH_MAX, }, @@ -4333,6 +4088,62 @@ static void offline_css(struct cgroup_subsys_state *css) RCU_INIT_POINTER(css->cgroup->subsys[ss->subsys_id], css); } +/** + * create_css - create a cgroup_subsys_state + * @cgrp: the cgroup new css will be associated with + * @ss: the subsys of new css + * + * Create a new css associated with @cgrp - @ss pair. On success, the new + * css is online and installed in @cgrp with all interface files created. + * Returns 0 on success, -errno on failure. + */ +static int create_css(struct cgroup *cgrp, struct cgroup_subsys *ss) +{ + struct cgroup *parent = cgrp->parent; + struct cgroup_subsys_state *css; + int err; + + lockdep_assert_held(&cgrp->dentry->d_inode->i_mutex); + lockdep_assert_held(&cgroup_mutex); + + css = ss->css_alloc(cgroup_css(parent, ss)); + if (IS_ERR(css)) + return PTR_ERR(css); + + err = percpu_ref_init(&css->refcnt, css_release); + if (err) + goto err_free; + + init_css(css, ss, cgrp); + + err = cgroup_populate_dir(cgrp, 1 << ss->subsys_id); + if (err) + goto err_free; + + err = online_css(css); + if (err) + goto err_free; + + dget(cgrp->dentry); + css_get(css->parent); + + if (ss->broken_hierarchy && !ss->warned_broken_hierarchy && + parent->parent) { + pr_warning("cgroup: %s (%d) created nested cgroup for controller \"%s\" which has incomplete hierarchy support. Nested cgroups may change behavior in the future.\n", + current->comm, current->pid, ss->name); + if (!strcmp(ss->name, "memory")) + pr_warning("cgroup: \"memory\" requires setting use_hierarchy to 1 on the root.\n"); + ss->warned_broken_hierarchy = true; + } + + return 0; + +err_free: + percpu_ref_cancel_init(&css->refcnt); + ss->css_free(css); + return err; +} + /* * cgroup_create - create a cgroup * @parent: cgroup that will be parent of the new cgroup @@ -4344,11 +4155,10 @@ static void offline_css(struct cgroup_subsys_state *css) static long cgroup_create(struct cgroup *parent, struct dentry *dentry, umode_t mode) { - struct cgroup_subsys_state *css_ar[CGROUP_SUBSYS_COUNT] = { }; struct cgroup *cgrp; struct cgroup_name *name; struct cgroupfs_root *root = parent->root; - int err = 0; + int ssid, err = 0; struct cgroup_subsys *ss; struct super_block *sb = root->sb; @@ -4404,23 +4214,6 @@ static long cgroup_create(struct cgroup *parent, struct dentry *dentry, if (test_bit(CGRP_CPUSET_CLONE_CHILDREN, &parent->flags)) set_bit(CGRP_CPUSET_CLONE_CHILDREN, &cgrp->flags); - for_each_root_subsys(root, ss) { - struct cgroup_subsys_state *css; - - css = ss->css_alloc(cgroup_css(parent, ss)); - if (IS_ERR(css)) { - err = PTR_ERR(css); - goto err_free_all; - } - css_ar[ss->subsys_id] = css; - - err = percpu_ref_init(&css->refcnt, css_release); - if (err) - goto err_free_all; - - init_css(css, ss, cgrp); - } - /* * Create directory. cgroup_create_file() returns with the new * directory locked on success so that it can be populated without @@ -4428,7 +4221,7 @@ static long cgroup_create(struct cgroup *parent, struct dentry *dentry, */ err = cgroup_create_file(dentry, S_IFDIR | mode, sb); if (err < 0) - goto err_free_all; + goto err_unlock; lockdep_assert_held(&dentry->d_inode->i_mutex); cgrp->serial_nr = cgroup_serial_nr_next++; @@ -4440,55 +4233,31 @@ static long cgroup_create(struct cgroup *parent, struct dentry *dentry, /* hold a ref to the parent's dentry */ dget(parent->dentry); - /* creation succeeded, notify subsystems */ - for_each_root_subsys(root, ss) { - struct cgroup_subsys_state *css = css_ar[ss->subsys_id]; - - err = online_css(css); - if (err) - goto err_destroy; - - /* each css holds a ref to the cgroup's dentry and parent css */ - dget(dentry); - css_get(css->parent); - - /* mark it consumed for error path */ - css_ar[ss->subsys_id] = NULL; - - if (ss->broken_hierarchy && !ss->warned_broken_hierarchy && - parent->parent) { - pr_warning("cgroup: %s (%d) created nested cgroup for controller \"%s\" which has incomplete hierarchy support. Nested cgroups may change behavior in the future.\n", - current->comm, current->pid, ss->name); - if (!strcmp(ss->name, "memory")) - pr_warning("cgroup: \"memory\" requires setting use_hierarchy to 1 on the root.\n"); - ss->warned_broken_hierarchy = true; - } - } - + /* + * @cgrp is now fully operational. If something fails after this + * point, it'll be released via the normal destruction path. + */ idr_replace(&root->cgroup_idr, cgrp, cgrp->id); err = cgroup_addrm_files(cgrp, cgroup_base_files, true); if (err) goto err_destroy; - err = cgroup_populate_dir(cgrp, root->subsys_mask); - if (err) - goto err_destroy; + /* let's create and online css's */ + for_each_subsys(ss, ssid) { + if (root->subsys_mask & (1 << ssid)) { + err = create_css(cgrp, ss); + if (err) + goto err_destroy; + } + } mutex_unlock(&cgroup_mutex); mutex_unlock(&cgrp->dentry->d_inode->i_mutex); return 0; -err_free_all: - for_each_root_subsys(root, ss) { - struct cgroup_subsys_state *css = css_ar[ss->subsys_id]; - - if (css) { - percpu_ref_cancel_init(&css->refcnt); - ss->css_free(css); - } - } +err_unlock: mutex_unlock(&cgroup_mutex); /* Release the reference count that we took on the superblock */ deactivate_super(sb); @@ -4501,14 +4270,6 @@ err_free_cgrp: return err; err_destroy: - for_each_root_subsys(root, ss) { - struct cgroup_subsys_state *css = css_ar[ss->subsys_id]; - - if (css) { - percpu_ref_cancel_init(&css->refcnt); - ss->css_free(css); - } - } cgroup_destroy_locked(cgrp); mutex_unlock(&cgroup_mutex); mutex_unlock(&dentry->d_inode->i_mutex); @@ -4631,10 +4392,10 @@ static int cgroup_destroy_locked(struct cgroup *cgrp) __releases(&cgroup_mutex) __acquires(&cgroup_mutex) { struct dentry *d = cgrp->dentry; - struct cgroup_event *event, *tmp; - struct cgroup_subsys *ss; + struct cgroup_subsys_state *css; struct cgroup *child; bool empty; + int ssid; lockdep_assert_held(&d->d_inode->i_mutex); lockdep_assert_held(&cgroup_mutex); @@ -4670,12 +4431,8 @@ static int cgroup_destroy_locked(struct cgroup *cgrp) * will be invoked to perform the rest of destruction once the * percpu refs of all css's are confirmed to be killed. */ - for_each_root_subsys(cgrp->root, ss) { - struct cgroup_subsys_state *css = cgroup_css(cgrp, ss); - - if (css) - kill_css(css); - } + for_each_css(css, ssid, cgrp) + kill_css(css); /* * Mark @cgrp dead. This prevents further task migration and child @@ -4710,18 +4467,6 @@ static int cgroup_destroy_locked(struct cgroup *cgrp) dget(d); cgroup_d_remove_dir(d); - /* - * Unregister events and notify userspace. - * Notify userspace about cgroup removing only after rmdir of cgroup - * directory to avoid race between userspace and kernelspace. - */ - spin_lock(&cgrp->event_list_lock); - list_for_each_entry_safe(event, tmp, &cgrp->event_list, list) { - list_del_init(&event->list); - schedule_work(&event->remove); - } - spin_unlock(&cgrp->event_list_lock); - return 0; }; @@ -4792,7 +4537,6 @@ static void __init cgroup_init_subsys(struct cgroup_subsys *ss) cgroup_init_cftsets(ss); /* Create the top cgroup state for this subsystem */ - list_add(&ss->sibling, &cgroup_dummy_root.subsys_list); ss->root = &cgroup_dummy_root; css = ss->css_alloc(cgroup_css(cgroup_dummy_top, ss)); /* We don't handle early failures gracefully */ @@ -4866,6 +4610,7 @@ int __init_or_module cgroup_load_subsys(struct cgroup_subsys *ss) cgroup_init_cftsets(ss); mutex_lock(&cgroup_mutex); + mutex_lock(&cgroup_root_mutex); cgroup_subsys[ss->subsys_id] = ss; /* @@ -4877,11 +4622,11 @@ int __init_or_module cgroup_load_subsys(struct cgroup_subsys *ss) if (IS_ERR(css)) { /* failure case - need to deassign the cgroup_subsys[] slot. */ cgroup_subsys[ss->subsys_id] = NULL; + mutex_unlock(&cgroup_root_mutex); mutex_unlock(&cgroup_mutex); return PTR_ERR(css); } - list_add(&ss->sibling, &cgroup_dummy_root.subsys_list); ss->root = &cgroup_dummy_root; /* our new subsystem will be attached to the dummy hierarchy. */ @@ -4911,14 +4656,18 @@ int __init_or_module cgroup_load_subsys(struct cgroup_subsys *ss) write_unlock(&css_set_lock); ret = online_css(css); - if (ret) + if (ret) { + ss->css_free(css); goto err_unload; + } /* success! */ + mutex_unlock(&cgroup_root_mutex); mutex_unlock(&cgroup_mutex); return 0; err_unload: + mutex_unlock(&cgroup_root_mutex); mutex_unlock(&cgroup_mutex); /* @ss can't be mounted here as try_module_get() would fail */ cgroup_unload_subsys(ss); @@ -4937,6 +4686,7 @@ EXPORT_SYMBOL_GPL(cgroup_load_subsys); void cgroup_unload_subsys(struct cgroup_subsys *ss) { struct cgrp_cset_link *link; + struct cgroup_subsys_state *css; BUG_ON(ss->module == NULL); @@ -4948,15 +4698,15 @@ void cgroup_unload_subsys(struct cgroup_subsys *ss) BUG_ON(ss->root != &cgroup_dummy_root); mutex_lock(&cgroup_mutex); + mutex_lock(&cgroup_root_mutex); - offline_css(cgroup_css(cgroup_dummy_top, ss)); + css = cgroup_css(cgroup_dummy_top, ss); + if (css) + offline_css(css); /* deassign the subsys_id */ cgroup_subsys[ss->subsys_id] = NULL; - /* remove subsystem from the dummy root's list of subsystems */ - list_del_init(&ss->sibling); - /* * disentangle the css from all css_sets attached to the dummy * top. as in loading, we need to pay our respects to the hashtable @@ -4979,9 +4729,11 @@ void cgroup_unload_subsys(struct cgroup_subsys *ss) * need to free before marking as null because ss->css_free needs * the cgrp->subsys pointer to find their state. */ - ss->css_free(cgroup_css(cgroup_dummy_top, ss)); + if (css) + ss->css_free(css); RCU_INIT_POINTER(cgroup_dummy_top->subsys[ss->subsys_id], NULL); + mutex_unlock(&cgroup_root_mutex); mutex_unlock(&cgroup_mutex); } EXPORT_SYMBOL_GPL(cgroup_unload_subsys); @@ -5100,6 +4852,15 @@ static int __init cgroup_wq_init(void) */ cgroup_destroy_wq = alloc_workqueue("cgroup_destroy", 0, 1); BUG_ON(!cgroup_destroy_wq); + + /* + * Used to destroy pidlists and separate to serve as flush domain. + * Cap @max_active to 1 too. + */ + cgroup_pidlist_destroy_wq = alloc_workqueue("cgroup_pidlist_destroy", + 0, 1); + BUG_ON(!cgroup_pidlist_destroy_wq); + return 0; } core_initcall(cgroup_wq_init); @@ -5143,11 +4904,12 @@ int proc_cgroup_show(struct seq_file *m, void *v) for_each_active_root(root) { struct cgroup_subsys *ss; struct cgroup *cgrp; - int count = 0; + int ssid, count = 0; seq_printf(m, "%d:", root->hierarchy_id); - for_each_root_subsys(root, ss) - seq_printf(m, "%s%s", count++ ? "," : "", ss->name); + for_each_subsys(ss, ssid) + if (root->subsys_mask & (1 << ssid)) + seq_printf(m, "%s%s", count++ ? "," : "", ss->name); if (strlen(root->name)) seq_printf(m, "%sname=%s", count ? "," : "", root->name); @@ -5488,16 +5250,16 @@ __setup("cgroup_disable=", cgroup_disable); * @dentry: directory dentry of interest * @ss: subsystem of interest * - * Must be called under RCU read lock. The caller is responsible for - * pinning the returned css if it needs to be accessed outside the RCU - * critical section. + * Must be called under cgroup_mutex or RCU read lock. The caller is + * responsible for pinning the returned css if it needs to be accessed + * outside the critical section. */ struct cgroup_subsys_state *css_from_dir(struct dentry *dentry, struct cgroup_subsys *ss) { struct cgroup *cgrp; - WARN_ON_ONCE(!rcu_read_lock_held()); + cgroup_assert_mutex_or_rcu_locked(); /* is @dentry a cgroup dir? */ if (!dentry->d_inode || @@ -5520,9 +5282,7 @@ struct cgroup_subsys_state *css_from_id(int id, struct cgroup_subsys *ss) { struct cgroup *cgrp; - rcu_lockdep_assert(rcu_read_lock_held() || - lockdep_is_held(&cgroup_mutex), - "css_from_id() needs proper protection"); + cgroup_assert_mutex_or_rcu_locked(); cgrp = idr_find(&ss->root->cgroup_idr, id); if (cgrp) @@ -5570,9 +5330,7 @@ static u64 current_css_set_refcount_read(struct cgroup_subsys_state *css, return count; } -static int current_css_set_cg_links_read(struct cgroup_subsys_state *css, - struct cftype *cft, - struct seq_file *seq) +static int current_css_set_cg_links_read(struct seq_file *seq, void *v) { struct cgrp_cset_link *link; struct css_set *cset; @@ -5597,9 +5355,9 @@ static int current_css_set_cg_links_read(struct cgroup_subsys_state *css, } #define MAX_TASKS_SHOWN_PER_CSS 25 -static int cgroup_css_links_read(struct cgroup_subsys_state *css, - struct cftype *cft, struct seq_file *seq) +static int cgroup_css_links_read(struct seq_file *seq, void *v) { + struct cgroup_subsys_state *css = seq_css(seq); struct cgrp_cset_link *link; read_lock(&css_set_lock); @@ -5645,12 +5403,12 @@ static struct cftype debug_files[] = { { .name = "current_css_set_cg_links", - .read_seq_string = current_css_set_cg_links_read, + .seq_show = current_css_set_cg_links_read, }, { .name = "cgroup_css_links", - .read_seq_string = cgroup_css_links_read, + .seq_show = cgroup_css_links_read, }, { diff --git a/kernel/cgroup_freezer.c b/kernel/cgroup_freezer.c index f0ff64d0ebaa..6c3154e477f6 100644 --- a/kernel/cgroup_freezer.c +++ b/kernel/cgroup_freezer.c @@ -301,10 +301,9 @@ out_unlock: spin_unlock_irq(&freezer->lock); } -static int freezer_read(struct cgroup_subsys_state *css, struct cftype *cft, - struct seq_file *m) +static int freezer_read(struct seq_file *m, void *v) { - struct cgroup_subsys_state *pos; + struct cgroup_subsys_state *css = seq_css(m), *pos; rcu_read_lock(); @@ -458,7 +457,7 @@ static struct cftype files[] = { { .name = "state", .flags = CFTYPE_NOT_ON_ROOT, - .read_seq_string = freezer_read, + .seq_show = freezer_read, .write_string = freezer_write, }, { diff --git a/kernel/context_tracking.c b/kernel/context_tracking.c index e5f3917aa05b..6cb20d2e7ee0 100644 --- a/kernel/context_tracking.c +++ b/kernel/context_tracking.c @@ -53,10 +53,10 @@ void context_tracking_user_enter(void) /* * Repeat the user_enter() check here because some archs may be calling * this from asm and if no CPU needs context tracking, they shouldn't - * go further. Repeat the check here until they support the static key - * check. + * go further. Repeat the check here until they support the inline static + * key check. */ - if (!static_key_false(&context_tracking_enabled)) + if (!context_tracking_is_enabled()) return; /* @@ -160,7 +160,7 @@ void context_tracking_user_exit(void) { unsigned long flags; - if (!static_key_false(&context_tracking_enabled)) + if (!context_tracking_is_enabled()) return; if (in_interrupt()) diff --git a/kernel/cpu/idle.c b/kernel/cpu/idle.c index 988573a9a387..277f494c2a9a 100644 --- a/kernel/cpu/idle.c +++ b/kernel/cpu/idle.c @@ -105,14 +105,17 @@ static void cpu_idle_loop(void) __current_set_polling(); } arch_cpu_idle_exit(); - /* - * We need to test and propagate the TIF_NEED_RESCHED - * bit here because we might not have send the - * reschedule IPI to idle tasks. - */ - if (tif_need_resched()) - set_preempt_need_resched(); } + + /* + * Since we fell out of the loop above, we know + * TIF_NEED_RESCHED must be set, propagate it into + * PREEMPT_NEED_RESCHED. + * + * This is required because for polling idle loops we will + * not have had an IPI to fold the state for us. + */ + preempt_set_need_resched(); tick_nohz_idle_exit(); schedule_preempt_disabled(); } diff --git a/kernel/cpuset.c b/kernel/cpuset.c index 4772034b4b17..4410ac6a55f1 100644 --- a/kernel/cpuset.c +++ b/kernel/cpuset.c @@ -1731,66 +1731,41 @@ out_unlock: * used, list of ranges of sequential numbers, is variable length, * and since these maps can change value dynamically, one could read * gibberish by doing partial reads while a list was changing. - * A single large read to a buffer that crosses a page boundary is - * ok, because the result being copied to user land is not recomputed - * across a page fault. */ - -static size_t cpuset_sprintf_cpulist(char *page, struct cpuset *cs) +static int cpuset_common_seq_show(struct seq_file *sf, void *v) { - size_t count; - - mutex_lock(&callback_mutex); - count = cpulist_scnprintf(page, PAGE_SIZE, cs->cpus_allowed); - mutex_unlock(&callback_mutex); + struct cpuset *cs = css_cs(seq_css(sf)); + cpuset_filetype_t type = seq_cft(sf)->private; + ssize_t count; + char *buf, *s; + int ret = 0; - return count; -} - -static size_t cpuset_sprintf_memlist(char *page, struct cpuset *cs) -{ - size_t count; + count = seq_get_buf(sf, &buf); + s = buf; mutex_lock(&callback_mutex); - count = nodelist_scnprintf(page, PAGE_SIZE, cs->mems_allowed); - mutex_unlock(&callback_mutex); - - return count; -} - -static ssize_t cpuset_common_file_read(struct cgroup_subsys_state *css, - struct cftype *cft, struct file *file, - char __user *buf, size_t nbytes, - loff_t *ppos) -{ - struct cpuset *cs = css_cs(css); - cpuset_filetype_t type = cft->private; - char *page; - ssize_t retval = 0; - char *s; - - if (!(page = (char *)__get_free_page(GFP_TEMPORARY))) - return -ENOMEM; - - s = page; switch (type) { case FILE_CPULIST: - s += cpuset_sprintf_cpulist(s, cs); + s += cpulist_scnprintf(s, count, cs->cpus_allowed); break; case FILE_MEMLIST: - s += cpuset_sprintf_memlist(s, cs); + s += nodelist_scnprintf(s, count, cs->mems_allowed); break; default: - retval = -EINVAL; - goto out; + ret = -EINVAL; + goto out_unlock; } - *s++ = '\n'; - retval = simple_read_from_buffer(buf, nbytes, ppos, page, s - page); -out: - free_page((unsigned long)page); - return retval; + if (s < buf + count - 1) { + *s++ = '\n'; + seq_commit(sf, s - buf); + } else { + seq_commit(sf, -1); + } +out_unlock: + mutex_unlock(&callback_mutex); + return ret; } static u64 cpuset_read_u64(struct cgroup_subsys_state *css, struct cftype *cft) @@ -1847,7 +1822,7 @@ static s64 cpuset_read_s64(struct cgroup_subsys_state *css, struct cftype *cft) static struct cftype files[] = { { .name = "cpus", - .read = cpuset_common_file_read, + .seq_show = cpuset_common_seq_show, .write_string = cpuset_write_resmask, .max_write_len = (100U + 6 * NR_CPUS), .private = FILE_CPULIST, @@ -1855,7 +1830,7 @@ static struct cftype files[] = { { .name = "mems", - .read = cpuset_common_file_read, + .seq_show = cpuset_common_seq_show, .write_string = cpuset_write_resmask, .max_write_len = (100U + 6 * MAX_NUMNODES), .private = FILE_MEMLIST, diff --git a/kernel/events/core.c b/kernel/events/core.c index f5744010a8d2..56003c6edfd3 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -119,7 +119,8 @@ static int cpu_function_call(int cpu, int (*func) (void *info), void *info) #define PERF_FLAG_ALL (PERF_FLAG_FD_NO_GROUP |\ PERF_FLAG_FD_OUTPUT |\ - PERF_FLAG_PID_CGROUP) + PERF_FLAG_PID_CGROUP |\ + PERF_FLAG_FD_CLOEXEC) /* * branch priv levels that need permission checks @@ -3542,7 +3543,7 @@ static void perf_event_for_each(struct perf_event *event, static int perf_event_period(struct perf_event *event, u64 __user *arg) { struct perf_event_context *ctx = event->ctx; - int ret = 0; + int ret = 0, active; u64 value; if (!is_sampling_event(event)) @@ -3566,6 +3567,20 @@ static int perf_event_period(struct perf_event *event, u64 __user *arg) event->attr.sample_period = value; event->hw.sample_period = value; } + + active = (event->state == PERF_EVENT_STATE_ACTIVE); + if (active) { + perf_pmu_disable(ctx->pmu); + event->pmu->stop(event, PERF_EF_UPDATE); + } + + local64_set(&event->hw.period_left, 0); + + if (active) { + event->pmu->start(event, PERF_EF_RELOAD); + perf_pmu_enable(ctx->pmu); + } + unlock: raw_spin_unlock_irq(&ctx->lock); @@ -6670,6 +6685,9 @@ perf_event_alloc(struct perf_event_attr *attr, int cpu, INIT_LIST_HEAD(&event->event_entry); INIT_LIST_HEAD(&event->sibling_list); INIT_LIST_HEAD(&event->rb_entry); + INIT_LIST_HEAD(&event->active_entry); + INIT_HLIST_NODE(&event->hlist_entry); + init_waitqueue_head(&event->waitq); init_irq_work(&event->pending, perf_pending_event); @@ -6980,6 +6998,7 @@ SYSCALL_DEFINE5(perf_event_open, int event_fd; int move_group = 0; int err; + int f_flags = O_RDWR; /* for future expandability... */ if (flags & ~PERF_FLAG_ALL) @@ -7008,7 +7027,10 @@ SYSCALL_DEFINE5(perf_event_open, if ((flags & PERF_FLAG_PID_CGROUP) && (pid == -1 || cpu == -1)) return -EINVAL; - event_fd = get_unused_fd(); + if (flags & PERF_FLAG_FD_CLOEXEC) + f_flags |= O_CLOEXEC; + + event_fd = get_unused_fd_flags(f_flags); if (event_fd < 0) return event_fd; @@ -7130,7 +7152,8 @@ SYSCALL_DEFINE5(perf_event_open, goto err_context; } - event_file = anon_inode_getfile("[perf_event]", &perf_fops, event, O_RDWR); + event_file = anon_inode_getfile("[perf_event]", &perf_fops, event, + f_flags); if (IS_ERR(event_file)) { err = PTR_ERR(event_file); goto err_context; diff --git a/kernel/events/ring_buffer.c b/kernel/events/ring_buffer.c index e8b168af135b..146a5792b1d2 100644 --- a/kernel/events/ring_buffer.c +++ b/kernel/events/ring_buffer.c @@ -61,19 +61,20 @@ again: * * kernel user * - * READ ->data_tail READ ->data_head - * smp_mb() (A) smp_rmb() (C) - * WRITE $data READ $data - * smp_wmb() (B) smp_mb() (D) - * STORE ->data_head WRITE ->data_tail + * if (LOAD ->data_tail) { LOAD ->data_head + * (A) smp_rmb() (C) + * STORE $data LOAD $data + * smp_wmb() (B) smp_mb() (D) + * STORE ->data_head STORE ->data_tail + * } * * Where A pairs with D, and B pairs with C. * - * I don't think A needs to be a full barrier because we won't in fact - * write data until we see the store from userspace. So we simply don't - * issue the data WRITE until we observe it. Be conservative for now. + * In our case (A) is a control dependency that separates the load of + * the ->data_tail and the stores of $data. In case ->data_tail + * indicates there is no room in the buffer to store $data we do not. * - * OTOH, D needs to be a full barrier since it separates the data READ + * D needs to be a full barrier since it separates the data READ * from the tail WRITE. * * For B a WMB is sufficient since it separates two WRITEs, and for C @@ -81,7 +82,7 @@ again: * * See perf_output_begin(). */ - smp_wmb(); + smp_wmb(); /* B, matches C */ rb->user_page->data_head = head; /* @@ -144,17 +145,26 @@ int perf_output_begin(struct perf_output_handle *handle, if (!rb->overwrite && unlikely(CIRC_SPACE(head, tail, perf_data_size(rb)) < size)) goto fail; + + /* + * The above forms a control dependency barrier separating the + * @tail load above from the data stores below. Since the @tail + * load is required to compute the branch to fail below. + * + * A, matches D; the full memory barrier userspace SHOULD issue + * after reading the data and before storing the new tail + * position. + * + * See perf_output_put_handle(). + */ + head += size; } while (local_cmpxchg(&rb->head, offset, head) != offset); /* - * Separate the userpage->tail read from the data stores below. - * Matches the MB userspace SHOULD issue after reading the data - * and before storing the new tail position. - * - * See perf_output_put_handle(). + * We rely on the implied barrier() by local_cmpxchg() to ensure + * none of the data stores below can be lifted up by the compiler. */ - smp_mb(); if (unlikely(head - local_read(&rb->wakeup) > rb->watermark)) local_add(rb->watermark, &rb->wakeup); diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c index 24b7d6ca871b..307d87c0991a 100644 --- a/kernel/events/uprobes.c +++ b/kernel/events/uprobes.c @@ -73,6 +73,17 @@ struct uprobe { struct inode *inode; /* Also hold a ref to inode */ loff_t offset; unsigned long flags; + + /* + * The generic code assumes that it has two members of unknown type + * owned by the arch-specific code: + * + * insn - copy_insn() saves the original instruction here for + * arch_uprobe_analyze_insn(). + * + * ixol - potentially modified instruction to execute out of + * line, copied to xol_area by xol_get_insn_slot(). + */ struct arch_uprobe arch; }; @@ -86,6 +97,29 @@ struct return_instance { }; /* + * Execute out of line area: anonymous executable mapping installed + * by the probed task to execute the copy of the original instruction + * mangled by set_swbp(). + * + * On a breakpoint hit, thread contests for a slot. It frees the + * slot after singlestep. Currently a fixed number of slots are + * allocated. + */ +struct xol_area { + wait_queue_head_t wq; /* if all slots are busy */ + atomic_t slot_count; /* number of in-use slots */ + unsigned long *bitmap; /* 0 = free slot */ + struct page *page; + + /* + * We keep the vma's vm_start rather than a pointer to the vma + * itself. The probed process or a naughty kernel module could make + * the vma go away, and we must handle that reasonably gracefully. + */ + unsigned long vaddr; /* Page(s) of instruction slots */ +}; + +/* * valid_vma: Verify if the specified vma is an executable vma * Relax restrictions while unregistering: vm_flags might have * changed after breakpoint was inserted. @@ -330,7 +364,7 @@ int __weak set_swbp(struct arch_uprobe *auprobe, struct mm_struct *mm, unsigned int __weak set_orig_insn(struct arch_uprobe *auprobe, struct mm_struct *mm, unsigned long vaddr) { - return uprobe_write_opcode(mm, vaddr, *(uprobe_opcode_t *)auprobe->insn); + return uprobe_write_opcode(mm, vaddr, *(uprobe_opcode_t *)&auprobe->insn); } static int match_uprobe(struct uprobe *l, struct uprobe *r) @@ -529,8 +563,8 @@ static int copy_insn(struct uprobe *uprobe, struct file *filp) { struct address_space *mapping = uprobe->inode->i_mapping; loff_t offs = uprobe->offset; - void *insn = uprobe->arch.insn; - int size = MAX_UINSN_BYTES; + void *insn = &uprobe->arch.insn; + int size = sizeof(uprobe->arch.insn); int len, err = -EIO; /* Copy only available bytes, -EIO if nothing was read */ @@ -569,7 +603,7 @@ static int prepare_uprobe(struct uprobe *uprobe, struct file *file, goto out; ret = -ENOTSUPP; - if (is_trap_insn((uprobe_opcode_t *)uprobe->arch.insn)) + if (is_trap_insn((uprobe_opcode_t *)&uprobe->arch.insn)) goto out; ret = arch_uprobe_analyze_insn(&uprobe->arch, mm, vaddr); @@ -1264,7 +1298,7 @@ static unsigned long xol_get_insn_slot(struct uprobe *uprobe) /* Initialize the slot */ copy_to_page(area->page, xol_vaddr, - uprobe->arch.ixol, sizeof(uprobe->arch.ixol)); + &uprobe->arch.ixol, sizeof(uprobe->arch.ixol)); /* * We probably need flush_icache_user_range() but it needs vma. * This should work on supported architectures too. @@ -1403,12 +1437,10 @@ static void uprobe_warn(struct task_struct *t, const char *msg) static void dup_xol_work(struct callback_head *work) { - kfree(work); - if (current->flags & PF_EXITING) return; - if (!__create_xol_area(current->utask->vaddr)) + if (!__create_xol_area(current->utask->dup_xol_addr)) uprobe_warn(current, "dup xol area"); } @@ -1419,7 +1451,6 @@ void uprobe_copy_process(struct task_struct *t, unsigned long flags) { struct uprobe_task *utask = current->utask; struct mm_struct *mm = current->mm; - struct callback_head *work; struct xol_area *area; t->utask = NULL; @@ -1441,14 +1472,9 @@ void uprobe_copy_process(struct task_struct *t, unsigned long flags) if (mm == t->mm) return; - /* TODO: move it into the union in uprobe_task */ - work = kmalloc(sizeof(*work), GFP_KERNEL); - if (!work) - return uprobe_warn(t, "dup xol area"); - - t->utask->vaddr = area->vaddr; - init_task_work(work, dup_xol_work); - task_work_add(t, work, true); + t->utask->dup_xol_addr = area->vaddr; + init_task_work(&t->utask->dup_xol_work, dup_xol_work); + task_work_add(t, &t->utask->dup_xol_work, true); } /* @@ -1828,6 +1854,10 @@ static void handle_swbp(struct pt_regs *regs) if (unlikely(!test_bit(UPROBE_COPY_INSN, &uprobe->flags))) goto out; + /* Tracing handlers use ->utask to communicate with fetch methods */ + if (!get_utask()) + goto out; + handler_chain(uprobe, regs); if (can_skip_sstep(uprobe, regs)) goto out; diff --git a/kernel/exit.c b/kernel/exit.c index a949819055d5..1e77fc645317 100644 --- a/kernel/exit.c +++ b/kernel/exit.c @@ -74,6 +74,7 @@ static void __unhash_process(struct task_struct *p, bool group_dead) __this_cpu_dec(process_counts); } list_del_rcu(&p->thread_group); + list_del_rcu(&p->thread_node); } /* diff --git a/kernel/fork.c b/kernel/fork.c index 5721f0e3f2da..a17621c6cd42 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -800,14 +800,11 @@ void mm_release(struct task_struct *tsk, struct mm_struct *mm) * Allocate a new mm structure and copy contents from the * mm structure of the passed in task structure. */ -struct mm_struct *dup_mm(struct task_struct *tsk) +static struct mm_struct *dup_mm(struct task_struct *tsk) { struct mm_struct *mm, *oldmm = current->mm; int err; - if (!oldmm) - return NULL; - mm = allocate_mm(); if (!mm) goto fail_nomem; @@ -1035,6 +1032,11 @@ static int copy_signal(unsigned long clone_flags, struct task_struct *tsk) sig->nr_threads = 1; atomic_set(&sig->live, 1); atomic_set(&sig->sigcnt, 1); + + /* list_add(thread_node, thread_head) without INIT_LIST_HEAD() */ + sig->thread_head = (struct list_head)LIST_HEAD_INIT(tsk->thread_node); + tsk->thread_node = (struct list_head)LIST_HEAD_INIT(sig->thread_head); + init_waitqueue_head(&sig->wait_chldexit); sig->curr_target = tsk; init_sigpending(&sig->shared_pending); @@ -1087,8 +1089,10 @@ static void rt_mutex_init_task(struct task_struct *p) { raw_spin_lock_init(&p->pi_lock); #ifdef CONFIG_RT_MUTEXES - plist_head_init(&p->pi_waiters); + p->pi_waiters = RB_ROOT; + p->pi_waiters_leftmost = NULL; p->pi_blocked_on = NULL; + p->pi_top_task = NULL; #endif } @@ -1172,7 +1176,7 @@ static struct task_struct *copy_process(unsigned long clone_flags, * do not allow it to share a thread group or signal handlers or * parent with the forking task. */ - if (clone_flags & (CLONE_SIGHAND | CLONE_PARENT)) { + if (clone_flags & CLONE_SIGHAND) { if ((clone_flags & (CLONE_NEWUSER | CLONE_NEWPID)) || (task_active_pid_ns(current) != current->nsproxy->pid_ns_for_children)) @@ -1222,7 +1226,6 @@ static struct task_struct *copy_process(unsigned long clone_flags, if (!try_module_get(task_thread_info(p)->exec_domain->module)) goto bad_fork_cleanup_count; - p->did_exec = 0; delayacct_tsk_init(p); /* Must remain after dup_task_struct() */ copy_flags(clone_flags, p); INIT_LIST_HEAD(&p->children); @@ -1311,7 +1314,9 @@ static struct task_struct *copy_process(unsigned long clone_flags, #endif /* Perform scheduler related setup. Assign this task to a CPU. */ - sched_fork(clone_flags, p); + retval = sched_fork(clone_flags, p); + if (retval) + goto bad_fork_cleanup_policy; retval = perf_event_init_task(p); if (retval) @@ -1403,13 +1408,11 @@ static struct task_struct *copy_process(unsigned long clone_flags, p->tgid = p->pid; } - p->pdeath_signal = 0; - p->exit_state = 0; - p->nr_dirtied = 0; p->nr_dirtied_pause = 128 >> (PAGE_SHIFT - 10); p->dirty_paused_when = 0; + p->pdeath_signal = 0; INIT_LIST_HEAD(&p->thread_group); p->task_works = NULL; @@ -1472,6 +1475,8 @@ static struct task_struct *copy_process(unsigned long clone_flags, atomic_inc(¤t->signal->sigcnt); list_add_tail_rcu(&p->thread_group, &p->group_leader->thread_group); + list_add_tail_rcu(&p->thread_node, + &p->signal->thread_head); } attach_pid(p, PIDTYPE_PID); nr_threads++; @@ -1645,7 +1650,7 @@ SYSCALL_DEFINE0(fork) return do_fork(SIGCHLD, 0, 0, NULL, NULL); #else /* can not support in nommu mode */ - return(-EINVAL); + return -EINVAL; #endif } #endif @@ -1653,7 +1658,7 @@ SYSCALL_DEFINE0(fork) #ifdef __ARCH_WANT_SYS_VFORK SYSCALL_DEFINE0(vfork) { - return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, 0, + return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, 0, 0, NULL, NULL); } #endif diff --git a/kernel/futex.c b/kernel/futex.c index f6ff0191ecf7..44a1261cb9ff 100644 --- a/kernel/futex.c +++ b/kernel/futex.c @@ -63,14 +63,101 @@ #include <linux/sched/rt.h> #include <linux/hugetlb.h> #include <linux/freezer.h> +#include <linux/bootmem.h> #include <asm/futex.h> #include "locking/rtmutex_common.h" -int __read_mostly futex_cmpxchg_enabled; +/* + * Basic futex operation and ordering guarantees: + * + * The waiter reads the futex value in user space and calls + * futex_wait(). This function computes the hash bucket and acquires + * the hash bucket lock. After that it reads the futex user space value + * again and verifies that the data has not changed. If it has not changed + * it enqueues itself into the hash bucket, releases the hash bucket lock + * and schedules. + * + * The waker side modifies the user space value of the futex and calls + * futex_wake(). This function computes the hash bucket and acquires the + * hash bucket lock. Then it looks for waiters on that futex in the hash + * bucket and wakes them. + * + * In futex wake up scenarios where no tasks are blocked on a futex, taking + * the hb spinlock can be avoided and simply return. In order for this + * optimization to work, ordering guarantees must exist so that the waiter + * being added to the list is acknowledged when the list is concurrently being + * checked by the waker, avoiding scenarios like the following: + * + * CPU 0 CPU 1 + * val = *futex; + * sys_futex(WAIT, futex, val); + * futex_wait(futex, val); + * uval = *futex; + * *futex = newval; + * sys_futex(WAKE, futex); + * futex_wake(futex); + * if (queue_empty()) + * return; + * if (uval == val) + * lock(hash_bucket(futex)); + * queue(); + * unlock(hash_bucket(futex)); + * schedule(); + * + * This would cause the waiter on CPU 0 to wait forever because it + * missed the transition of the user space value from val to newval + * and the waker did not find the waiter in the hash bucket queue. + * + * The correct serialization ensures that a waiter either observes + * the changed user space value before blocking or is woken by a + * concurrent waker: + * + * CPU 0 CPU 1 + * val = *futex; + * sys_futex(WAIT, futex, val); + * futex_wait(futex, val); + * + * waiters++; + * mb(); (A) <-- paired with -. + * | + * lock(hash_bucket(futex)); | + * | + * uval = *futex; | + * | *futex = newval; + * | sys_futex(WAKE, futex); + * | futex_wake(futex); + * | + * `-------> mb(); (B) + * if (uval == val) + * queue(); + * unlock(hash_bucket(futex)); + * schedule(); if (waiters) + * lock(hash_bucket(futex)); + * wake_waiters(futex); + * unlock(hash_bucket(futex)); + * + * Where (A) orders the waiters increment and the futex value read -- this + * is guaranteed by the head counter in the hb spinlock; and where (B) + * orders the write to futex and the waiters read -- this is done by the + * barriers in get_futex_key_refs(), through either ihold or atomic_inc, + * depending on the futex type. + * + * This yields the following case (where X:=waiters, Y:=futex): + * + * X = Y = 0 + * + * w[X]=1 w[Y]=1 + * MB MB + * r[Y]=y r[X]=x + * + * Which guarantees that x==0 && y==0 is impossible; which translates back into + * the guarantee that we cannot both miss the futex variable change and the + * enqueue. + */ -#define FUTEX_HASHBITS (CONFIG_BASE_SMALL ? 4 : 8) +int __read_mostly futex_cmpxchg_enabled; /* * Futex flags used to encode options to functions and preserve them across @@ -149,9 +236,41 @@ static const struct futex_q futex_q_init = { struct futex_hash_bucket { spinlock_t lock; struct plist_head chain; -}; +} ____cacheline_aligned_in_smp; -static struct futex_hash_bucket futex_queues[1<<FUTEX_HASHBITS]; +static unsigned long __read_mostly futex_hashsize; + +static struct futex_hash_bucket *futex_queues; + +static inline void futex_get_mm(union futex_key *key) +{ + atomic_inc(&key->private.mm->mm_count); + /* + * Ensure futex_get_mm() implies a full barrier such that + * get_futex_key() implies a full barrier. This is relied upon + * as full barrier (B), see the ordering comment above. + */ + smp_mb__after_atomic_inc(); +} + +static inline bool hb_waiters_pending(struct futex_hash_bucket *hb) +{ +#ifdef CONFIG_SMP + /* + * Tasks trying to enter the critical region are most likely + * potential waiters that will be added to the plist. Ensure + * that wakers won't miss to-be-slept tasks in the window between + * the wait call and the actual plist_add. + */ + if (spin_is_locked(&hb->lock)) + return true; + smp_rmb(); /* Make sure we check the lock state first */ + + return !plist_head_empty(&hb->chain); +#else + return true; +#endif +} /* * We hash on the keys returned from get_futex_key (see below). @@ -161,7 +280,7 @@ static struct futex_hash_bucket *hash_futex(union futex_key *key) u32 hash = jhash2((u32*)&key->both.word, (sizeof(key->both.word)+sizeof(key->both.ptr))/4, key->both.offset); - return &futex_queues[hash & ((1 << FUTEX_HASHBITS)-1)]; + return &futex_queues[hash & (futex_hashsize - 1)]; } /* @@ -187,10 +306,10 @@ static void get_futex_key_refs(union futex_key *key) switch (key->both.offset & (FUT_OFF_INODE|FUT_OFF_MMSHARED)) { case FUT_OFF_INODE: - ihold(key->shared.inode); + ihold(key->shared.inode); /* implies MB (B) */ break; case FUT_OFF_MMSHARED: - atomic_inc(&key->private.mm->mm_count); + futex_get_mm(key); /* implies MB (B) */ break; } } @@ -264,7 +383,7 @@ get_futex_key(u32 __user *uaddr, int fshared, union futex_key *key, int rw) if (!fshared) { key->private.mm = mm; key->private.address = address; - get_futex_key_refs(key); + get_futex_key_refs(key); /* implies MB (B) */ return 0; } @@ -371,7 +490,7 @@ again: key->shared.pgoff = basepage_index(page); } - get_futex_key_refs(key); + get_futex_key_refs(key); /* implies MB (B) */ out: unlock_page(page_head); @@ -598,13 +717,10 @@ lookup_pi_state(u32 uval, struct futex_hash_bucket *hb, { struct futex_pi_state *pi_state = NULL; struct futex_q *this, *next; - struct plist_head *head; struct task_struct *p; pid_t pid = uval & FUTEX_TID_MASK; - head = &hb->chain; - - plist_for_each_entry_safe(this, next, head, list) { + plist_for_each_entry_safe(this, next, &hb->chain, list) { if (match_futex(&this->key, key)) { /* * Another waiter already exists - bump up @@ -986,7 +1102,6 @@ futex_wake(u32 __user *uaddr, unsigned int flags, int nr_wake, u32 bitset) { struct futex_hash_bucket *hb; struct futex_q *this, *next; - struct plist_head *head; union futex_key key = FUTEX_KEY_INIT; int ret; @@ -998,10 +1113,14 @@ futex_wake(u32 __user *uaddr, unsigned int flags, int nr_wake, u32 bitset) goto out; hb = hash_futex(&key); + + /* Make sure we really have tasks to wakeup */ + if (!hb_waiters_pending(hb)) + goto out_put_key; + spin_lock(&hb->lock); - head = &hb->chain; - plist_for_each_entry_safe(this, next, head, list) { + plist_for_each_entry_safe(this, next, &hb->chain, list) { if (match_futex (&this->key, &key)) { if (this->pi_state || this->rt_waiter) { ret = -EINVAL; @@ -1019,6 +1138,7 @@ futex_wake(u32 __user *uaddr, unsigned int flags, int nr_wake, u32 bitset) } spin_unlock(&hb->lock); +out_put_key: put_futex_key(&key); out: return ret; @@ -1034,7 +1154,6 @@ futex_wake_op(u32 __user *uaddr1, unsigned int flags, u32 __user *uaddr2, { union futex_key key1 = FUTEX_KEY_INIT, key2 = FUTEX_KEY_INIT; struct futex_hash_bucket *hb1, *hb2; - struct plist_head *head; struct futex_q *this, *next; int ret, op_ret; @@ -1082,9 +1201,7 @@ retry_private: goto retry; } - head = &hb1->chain; - - plist_for_each_entry_safe(this, next, head, list) { + plist_for_each_entry_safe(this, next, &hb1->chain, list) { if (match_futex (&this->key, &key1)) { if (this->pi_state || this->rt_waiter) { ret = -EINVAL; @@ -1097,10 +1214,8 @@ retry_private: } if (op_ret > 0) { - head = &hb2->chain; - op_ret = 0; - plist_for_each_entry_safe(this, next, head, list) { + plist_for_each_entry_safe(this, next, &hb2->chain, list) { if (match_futex (&this->key, &key2)) { if (this->pi_state || this->rt_waiter) { ret = -EINVAL; @@ -1270,7 +1385,6 @@ static int futex_requeue(u32 __user *uaddr1, unsigned int flags, int drop_count = 0, task_count = 0, ret; struct futex_pi_state *pi_state = NULL; struct futex_hash_bucket *hb1, *hb2; - struct plist_head *head1; struct futex_q *this, *next; u32 curval2; @@ -1393,8 +1507,7 @@ retry_private: } } - head1 = &hb1->chain; - plist_for_each_entry_safe(this, next, head1, list) { + plist_for_each_entry_safe(this, next, &hb1->chain, list) { if (task_count - nr_wake >= nr_requeue) break; @@ -1489,12 +1602,12 @@ static inline struct futex_hash_bucket *queue_lock(struct futex_q *q) hb = hash_futex(&q->key); q->lock_ptr = &hb->lock; - spin_lock(&hb->lock); + spin_lock(&hb->lock); /* implies MB (A) */ return hb; } static inline void -queue_unlock(struct futex_q *q, struct futex_hash_bucket *hb) +queue_unlock(struct futex_hash_bucket *hb) __releases(&hb->lock) { spin_unlock(&hb->lock); @@ -1867,7 +1980,7 @@ retry_private: ret = get_futex_value_locked(&uval, uaddr); if (ret) { - queue_unlock(q, *hb); + queue_unlock(*hb); ret = get_user(uval, uaddr); if (ret) @@ -1881,7 +1994,7 @@ retry_private: } if (uval != val) { - queue_unlock(q, *hb); + queue_unlock(*hb); ret = -EWOULDBLOCK; } @@ -2029,7 +2142,7 @@ retry_private: * Task is exiting and we just wait for the * exit to complete. */ - queue_unlock(&q, hb); + queue_unlock(hb); put_futex_key(&q.key); cond_resched(); goto retry; @@ -2081,7 +2194,7 @@ retry_private: goto out_put_key; out_unlock_put_key: - queue_unlock(&q, hb); + queue_unlock(hb); out_put_key: put_futex_key(&q.key); @@ -2091,7 +2204,7 @@ out: return ret != -EINTR ? ret : -ERESTARTNOINTR; uaddr_faulted: - queue_unlock(&q, hb); + queue_unlock(hb); ret = fault_in_user_writeable(uaddr); if (ret) @@ -2113,7 +2226,6 @@ static int futex_unlock_pi(u32 __user *uaddr, unsigned int flags) { struct futex_hash_bucket *hb; struct futex_q *this, *next; - struct plist_head *head; union futex_key key = FUTEX_KEY_INIT; u32 uval, vpid = task_pid_vnr(current); int ret; @@ -2153,9 +2265,7 @@ retry: * Ok, other tasks may need to be woken up - check waiters * and do the wakeup if necessary: */ - head = &hb->chain; - - plist_for_each_entry_safe(this, next, head, list) { + plist_for_each_entry_safe(this, next, &hb->chain, list) { if (!match_futex (&this->key, &key)) continue; ret = wake_futex_pi(uaddr, uval, this); @@ -2316,6 +2426,8 @@ static int futex_wait_requeue_pi(u32 __user *uaddr, unsigned int flags, * code while we sleep on uaddr. */ debug_rt_mutex_init_waiter(&rt_waiter); + RB_CLEAR_NODE(&rt_waiter.pi_tree_entry); + RB_CLEAR_NODE(&rt_waiter.tree_entry); rt_waiter.task = NULL; ret = get_futex_key(uaddr2, flags & FLAGS_SHARED, &key2, VERIFY_WRITE); @@ -2734,8 +2846,21 @@ SYSCALL_DEFINE6(futex, u32 __user *, uaddr, int, op, u32, val, static int __init futex_init(void) { u32 curval; - int i; + unsigned int futex_shift; + unsigned long i; + +#if CONFIG_BASE_SMALL + futex_hashsize = 16; +#else + futex_hashsize = roundup_pow_of_two(256 * num_possible_cpus()); +#endif + futex_queues = alloc_large_system_hash("futex", sizeof(*futex_queues), + futex_hashsize, 0, + futex_hashsize < 256 ? HASH_SMALL : 0, + &futex_shift, NULL, + futex_hashsize, futex_hashsize); + futex_hashsize = 1UL << futex_shift; /* * This will fail and we want it. Some arch implementations do * runtime detection of the futex_atomic_cmpxchg_inatomic() @@ -2749,7 +2874,7 @@ static int __init futex_init(void) if (cmpxchg_futex_value_locked(&curval, NULL, 0, 0) == -EFAULT) futex_cmpxchg_enabled = 1; - for (i = 0; i < ARRAY_SIZE(futex_queues); i++) { + for (i = 0; i < futex_hashsize; i++) { plist_head_init(&futex_queues[i].chain); spin_lock_init(&futex_queues[i].lock); } diff --git a/kernel/hrtimer.c b/kernel/hrtimer.c index 383319bae3f7..09094361dce5 100644 --- a/kernel/hrtimer.c +++ b/kernel/hrtimer.c @@ -46,6 +46,7 @@ #include <linux/sched.h> #include <linux/sched/sysctl.h> #include <linux/sched/rt.h> +#include <linux/sched/deadline.h> #include <linux/timer.h> #include <linux/freezer.h> @@ -1610,7 +1611,7 @@ long hrtimer_nanosleep(struct timespec *rqtp, struct timespec __user *rmtp, unsigned long slack; slack = current->timer_slack_ns; - if (rt_task(current)) + if (dl_task(current) || rt_task(current)) slack = 0; hrtimer_init_on_stack(&t.timer, clockid, mode); diff --git a/kernel/kexec.c b/kernel/kexec.c index 9c970167e402..ac738781d356 100644 --- a/kernel/kexec.c +++ b/kernel/kexec.c @@ -932,6 +932,7 @@ static int kimage_load_segment(struct kimage *image, */ struct kimage *kexec_image; struct kimage *kexec_crash_image; +int kexec_load_disabled; static DEFINE_MUTEX(kexec_mutex); @@ -942,7 +943,7 @@ SYSCALL_DEFINE4(kexec_load, unsigned long, entry, unsigned long, nr_segments, int result; /* We only trust the superuser with rebooting the system. */ - if (!capable(CAP_SYS_BOOT)) + if (!capable(CAP_SYS_BOOT) || kexec_load_disabled) return -EPERM; /* diff --git a/kernel/ksysfs.c b/kernel/ksysfs.c index 9659d38e008f..d945a949760f 100644 --- a/kernel/ksysfs.c +++ b/kernel/ksysfs.c @@ -126,7 +126,7 @@ static ssize_t vmcoreinfo_show(struct kobject *kobj, { return sprintf(buf, "%lx %x\n", paddr_vmcoreinfo_note(), - (unsigned int)vmcoreinfo_max_size); + (unsigned int)sizeof(vmcoreinfo_note)); } KERNEL_ATTR_RO(vmcoreinfo); diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c index 576ba756a32d..eb8a54783fa0 100644 --- a/kernel/locking/lockdep.c +++ b/kernel/locking/lockdep.c @@ -590,6 +590,7 @@ static int very_verbose(struct lock_class *class) /* * Is this the address of a static object: */ +#ifdef __KERNEL__ static int static_obj(void *obj) { unsigned long start = (unsigned long) &_stext, @@ -616,6 +617,7 @@ static int static_obj(void *obj) */ return is_module_address(addr) || is_module_percpu_address(addr); } +#endif /* * To make lock name printouts unique, we calculate a unique @@ -4115,6 +4117,7 @@ void debug_check_no_locks_held(void) } EXPORT_SYMBOL_GPL(debug_check_no_locks_held); +#ifdef __KERNEL__ void debug_show_all_locks(void) { struct task_struct *g, *p; @@ -4172,6 +4175,7 @@ retry: read_unlock(&tasklist_lock); } EXPORT_SYMBOL_GPL(debug_show_all_locks); +#endif /* * Careful: only use this function if you are sure that diff --git a/kernel/locking/mutex-debug.c b/kernel/locking/mutex-debug.c index 7e3443fe1f48..faf6f5b53e77 100644 --- a/kernel/locking/mutex-debug.c +++ b/kernel/locking/mutex-debug.c @@ -75,7 +75,12 @@ void debug_mutex_unlock(struct mutex *lock) return; DEBUG_LOCKS_WARN_ON(lock->magic != lock); - DEBUG_LOCKS_WARN_ON(lock->owner != current); + + if (!lock->owner) + DEBUG_LOCKS_WARN_ON(!lock->owner); + else + DEBUG_LOCKS_WARN_ON(lock->owner != current); + DEBUG_LOCKS_WARN_ON(!lock->wait_list.prev && !lock->wait_list.next); mutex_clear_owner(lock); } diff --git a/kernel/locking/rtmutex-debug.c b/kernel/locking/rtmutex-debug.c index 13b243a323fa..49b2ed3dced8 100644 --- a/kernel/locking/rtmutex-debug.c +++ b/kernel/locking/rtmutex-debug.c @@ -24,7 +24,7 @@ #include <linux/kallsyms.h> #include <linux/syscalls.h> #include <linux/interrupt.h> -#include <linux/plist.h> +#include <linux/rbtree.h> #include <linux/fs.h> #include <linux/debug_locks.h> @@ -57,7 +57,7 @@ static void printk_lock(struct rt_mutex *lock, int print_owner) void rt_mutex_debug_task_free(struct task_struct *task) { - DEBUG_LOCKS_WARN_ON(!plist_head_empty(&task->pi_waiters)); + DEBUG_LOCKS_WARN_ON(!RB_EMPTY_ROOT(&task->pi_waiters)); DEBUG_LOCKS_WARN_ON(task->pi_blocked_on); } @@ -154,16 +154,12 @@ void debug_rt_mutex_proxy_unlock(struct rt_mutex *lock) void debug_rt_mutex_init_waiter(struct rt_mutex_waiter *waiter) { memset(waiter, 0x11, sizeof(*waiter)); - plist_node_init(&waiter->list_entry, MAX_PRIO); - plist_node_init(&waiter->pi_list_entry, MAX_PRIO); waiter->deadlock_task_pid = NULL; } void debug_rt_mutex_free_waiter(struct rt_mutex_waiter *waiter) { put_pid(waiter->deadlock_task_pid); - DEBUG_LOCKS_WARN_ON(!plist_node_empty(&waiter->list_entry)); - DEBUG_LOCKS_WARN_ON(!plist_node_empty(&waiter->pi_list_entry)); memset(waiter, 0x22, sizeof(*waiter)); } diff --git a/kernel/locking/rtmutex.c b/kernel/locking/rtmutex.c index 0dd6aec1cb6a..2e960a2bab81 100644 --- a/kernel/locking/rtmutex.c +++ b/kernel/locking/rtmutex.c @@ -14,6 +14,7 @@ #include <linux/export.h> #include <linux/sched.h> #include <linux/sched/rt.h> +#include <linux/sched/deadline.h> #include <linux/timer.h> #include "rtmutex_common.h" @@ -91,10 +92,107 @@ static inline void mark_rt_mutex_waiters(struct rt_mutex *lock) } #endif +static inline int +rt_mutex_waiter_less(struct rt_mutex_waiter *left, + struct rt_mutex_waiter *right) +{ + if (left->prio < right->prio) + return 1; + + /* + * If both waiters have dl_prio(), we check the deadlines of the + * associated tasks. + * If left waiter has a dl_prio(), and we didn't return 1 above, + * then right waiter has a dl_prio() too. + */ + if (dl_prio(left->prio)) + return (left->task->dl.deadline < right->task->dl.deadline); + + return 0; +} + +static void +rt_mutex_enqueue(struct rt_mutex *lock, struct rt_mutex_waiter *waiter) +{ + struct rb_node **link = &lock->waiters.rb_node; + struct rb_node *parent = NULL; + struct rt_mutex_waiter *entry; + int leftmost = 1; + + while (*link) { + parent = *link; + entry = rb_entry(parent, struct rt_mutex_waiter, tree_entry); + if (rt_mutex_waiter_less(waiter, entry)) { + link = &parent->rb_left; + } else { + link = &parent->rb_right; + leftmost = 0; + } + } + + if (leftmost) + lock->waiters_leftmost = &waiter->tree_entry; + + rb_link_node(&waiter->tree_entry, parent, link); + rb_insert_color(&waiter->tree_entry, &lock->waiters); +} + +static void +rt_mutex_dequeue(struct rt_mutex *lock, struct rt_mutex_waiter *waiter) +{ + if (RB_EMPTY_NODE(&waiter->tree_entry)) + return; + + if (lock->waiters_leftmost == &waiter->tree_entry) + lock->waiters_leftmost = rb_next(&waiter->tree_entry); + + rb_erase(&waiter->tree_entry, &lock->waiters); + RB_CLEAR_NODE(&waiter->tree_entry); +} + +static void +rt_mutex_enqueue_pi(struct task_struct *task, struct rt_mutex_waiter *waiter) +{ + struct rb_node **link = &task->pi_waiters.rb_node; + struct rb_node *parent = NULL; + struct rt_mutex_waiter *entry; + int leftmost = 1; + + while (*link) { + parent = *link; + entry = rb_entry(parent, struct rt_mutex_waiter, pi_tree_entry); + if (rt_mutex_waiter_less(waiter, entry)) { + link = &parent->rb_left; + } else { + link = &parent->rb_right; + leftmost = 0; + } + } + + if (leftmost) + task->pi_waiters_leftmost = &waiter->pi_tree_entry; + + rb_link_node(&waiter->pi_tree_entry, parent, link); + rb_insert_color(&waiter->pi_tree_entry, &task->pi_waiters); +} + +static void +rt_mutex_dequeue_pi(struct task_struct *task, struct rt_mutex_waiter *waiter) +{ + if (RB_EMPTY_NODE(&waiter->pi_tree_entry)) + return; + + if (task->pi_waiters_leftmost == &waiter->pi_tree_entry) + task->pi_waiters_leftmost = rb_next(&waiter->pi_tree_entry); + + rb_erase(&waiter->pi_tree_entry, &task->pi_waiters); + RB_CLEAR_NODE(&waiter->pi_tree_entry); +} + /* - * Calculate task priority from the waiter list priority + * Calculate task priority from the waiter tree priority * - * Return task->normal_prio when the waiter list is empty or when + * Return task->normal_prio when the waiter tree is empty or when * the waiter is not allowed to do priority boosting */ int rt_mutex_getprio(struct task_struct *task) @@ -102,10 +200,18 @@ int rt_mutex_getprio(struct task_struct *task) if (likely(!task_has_pi_waiters(task))) return task->normal_prio; - return min(task_top_pi_waiter(task)->pi_list_entry.prio, + return min(task_top_pi_waiter(task)->prio, task->normal_prio); } +struct task_struct *rt_mutex_get_top_task(struct task_struct *task) +{ + if (likely(!task_has_pi_waiters(task))) + return NULL; + + return task_top_pi_waiter(task)->task; +} + /* * Adjust the priority of a task, after its pi_waiters got modified. * @@ -115,7 +221,7 @@ static void __rt_mutex_adjust_prio(struct task_struct *task) { int prio = rt_mutex_getprio(task); - if (task->prio != prio) + if (task->prio != prio || dl_prio(prio)) rt_mutex_setprio(task, prio); } @@ -233,7 +339,7 @@ static int rt_mutex_adjust_prio_chain(struct task_struct *task, * When deadlock detection is off then we check, if further * priority adjustment is necessary. */ - if (!detect_deadlock && waiter->list_entry.prio == task->prio) + if (!detect_deadlock && waiter->prio == task->prio) goto out_unlock_pi; lock = waiter->lock; @@ -254,9 +360,9 @@ static int rt_mutex_adjust_prio_chain(struct task_struct *task, top_waiter = rt_mutex_top_waiter(lock); /* Requeue the waiter */ - plist_del(&waiter->list_entry, &lock->wait_list); - waiter->list_entry.prio = task->prio; - plist_add(&waiter->list_entry, &lock->wait_list); + rt_mutex_dequeue(lock, waiter); + waiter->prio = task->prio; + rt_mutex_enqueue(lock, waiter); /* Release the task */ raw_spin_unlock_irqrestore(&task->pi_lock, flags); @@ -280,17 +386,15 @@ static int rt_mutex_adjust_prio_chain(struct task_struct *task, if (waiter == rt_mutex_top_waiter(lock)) { /* Boost the owner */ - plist_del(&top_waiter->pi_list_entry, &task->pi_waiters); - waiter->pi_list_entry.prio = waiter->list_entry.prio; - plist_add(&waiter->pi_list_entry, &task->pi_waiters); + rt_mutex_dequeue_pi(task, top_waiter); + rt_mutex_enqueue_pi(task, waiter); __rt_mutex_adjust_prio(task); } else if (top_waiter == waiter) { /* Deboost the owner */ - plist_del(&waiter->pi_list_entry, &task->pi_waiters); + rt_mutex_dequeue_pi(task, waiter); waiter = rt_mutex_top_waiter(lock); - waiter->pi_list_entry.prio = waiter->list_entry.prio; - plist_add(&waiter->pi_list_entry, &task->pi_waiters); + rt_mutex_enqueue_pi(task, waiter); __rt_mutex_adjust_prio(task); } @@ -355,7 +459,7 @@ static int try_to_take_rt_mutex(struct rt_mutex *lock, struct task_struct *task, * 3) it is top waiter */ if (rt_mutex_has_waiters(lock)) { - if (task->prio >= rt_mutex_top_waiter(lock)->list_entry.prio) { + if (task->prio >= rt_mutex_top_waiter(lock)->prio) { if (!waiter || waiter != rt_mutex_top_waiter(lock)) return 0; } @@ -369,7 +473,7 @@ static int try_to_take_rt_mutex(struct rt_mutex *lock, struct task_struct *task, /* remove the queued waiter. */ if (waiter) { - plist_del(&waiter->list_entry, &lock->wait_list); + rt_mutex_dequeue(lock, waiter); task->pi_blocked_on = NULL; } @@ -379,8 +483,7 @@ static int try_to_take_rt_mutex(struct rt_mutex *lock, struct task_struct *task, */ if (rt_mutex_has_waiters(lock)) { top = rt_mutex_top_waiter(lock); - top->pi_list_entry.prio = top->list_entry.prio; - plist_add(&top->pi_list_entry, &task->pi_waiters); + rt_mutex_enqueue_pi(task, top); } raw_spin_unlock_irqrestore(&task->pi_lock, flags); } @@ -416,13 +519,12 @@ static int task_blocks_on_rt_mutex(struct rt_mutex *lock, __rt_mutex_adjust_prio(task); waiter->task = task; waiter->lock = lock; - plist_node_init(&waiter->list_entry, task->prio); - plist_node_init(&waiter->pi_list_entry, task->prio); + waiter->prio = task->prio; /* Get the top priority waiter on the lock */ if (rt_mutex_has_waiters(lock)) top_waiter = rt_mutex_top_waiter(lock); - plist_add(&waiter->list_entry, &lock->wait_list); + rt_mutex_enqueue(lock, waiter); task->pi_blocked_on = waiter; @@ -433,8 +535,8 @@ static int task_blocks_on_rt_mutex(struct rt_mutex *lock, if (waiter == rt_mutex_top_waiter(lock)) { raw_spin_lock_irqsave(&owner->pi_lock, flags); - plist_del(&top_waiter->pi_list_entry, &owner->pi_waiters); - plist_add(&waiter->pi_list_entry, &owner->pi_waiters); + rt_mutex_dequeue_pi(owner, top_waiter); + rt_mutex_enqueue_pi(owner, waiter); __rt_mutex_adjust_prio(owner); if (owner->pi_blocked_on) @@ -486,7 +588,7 @@ static void wakeup_next_waiter(struct rt_mutex *lock) * boosted mode and go back to normal after releasing * lock->wait_lock. */ - plist_del(&waiter->pi_list_entry, ¤t->pi_waiters); + rt_mutex_dequeue_pi(current, waiter); rt_mutex_set_owner(lock, NULL); @@ -510,7 +612,7 @@ static void remove_waiter(struct rt_mutex *lock, int chain_walk = 0; raw_spin_lock_irqsave(¤t->pi_lock, flags); - plist_del(&waiter->list_entry, &lock->wait_list); + rt_mutex_dequeue(lock, waiter); current->pi_blocked_on = NULL; raw_spin_unlock_irqrestore(¤t->pi_lock, flags); @@ -521,13 +623,13 @@ static void remove_waiter(struct rt_mutex *lock, raw_spin_lock_irqsave(&owner->pi_lock, flags); - plist_del(&waiter->pi_list_entry, &owner->pi_waiters); + rt_mutex_dequeue_pi(owner, waiter); if (rt_mutex_has_waiters(lock)) { struct rt_mutex_waiter *next; next = rt_mutex_top_waiter(lock); - plist_add(&next->pi_list_entry, &owner->pi_waiters); + rt_mutex_enqueue_pi(owner, next); } __rt_mutex_adjust_prio(owner); @@ -537,8 +639,6 @@ static void remove_waiter(struct rt_mutex *lock, raw_spin_unlock_irqrestore(&owner->pi_lock, flags); } - WARN_ON(!plist_node_empty(&waiter->pi_list_entry)); - if (!chain_walk) return; @@ -565,7 +665,8 @@ void rt_mutex_adjust_pi(struct task_struct *task) raw_spin_lock_irqsave(&task->pi_lock, flags); waiter = task->pi_blocked_on; - if (!waiter || waiter->list_entry.prio == task->prio) { + if (!waiter || (waiter->prio == task->prio && + !dl_prio(task->prio))) { raw_spin_unlock_irqrestore(&task->pi_lock, flags); return; } @@ -638,6 +739,8 @@ rt_mutex_slowlock(struct rt_mutex *lock, int state, int ret = 0; debug_rt_mutex_init_waiter(&waiter); + RB_CLEAR_NODE(&waiter.pi_tree_entry); + RB_CLEAR_NODE(&waiter.tree_entry); raw_spin_lock(&lock->wait_lock); @@ -904,7 +1007,8 @@ void __rt_mutex_init(struct rt_mutex *lock, const char *name) { lock->owner = NULL; raw_spin_lock_init(&lock->wait_lock); - plist_head_init(&lock->wait_list); + lock->waiters = RB_ROOT; + lock->waiters_leftmost = NULL; debug_rt_mutex_init(lock, name); } diff --git a/kernel/locking/rtmutex_common.h b/kernel/locking/rtmutex_common.h index 53a66c85261b..7431a9c86f35 100644 --- a/kernel/locking/rtmutex_common.h +++ b/kernel/locking/rtmutex_common.h @@ -40,13 +40,13 @@ extern void schedule_rt_mutex_test(struct rt_mutex *lock); * This is the control structure for tasks blocked on a rt_mutex, * which is allocated on the kernel stack on of the blocked task. * - * @list_entry: pi node to enqueue into the mutex waiters list - * @pi_list_entry: pi node to enqueue into the mutex owner waiters list + * @tree_entry: pi node to enqueue into the mutex waiters tree + * @pi_tree_entry: pi node to enqueue into the mutex owner waiters tree * @task: task reference to the blocked task */ struct rt_mutex_waiter { - struct plist_node list_entry; - struct plist_node pi_list_entry; + struct rb_node tree_entry; + struct rb_node pi_tree_entry; struct task_struct *task; struct rt_mutex *lock; #ifdef CONFIG_DEBUG_RT_MUTEXES @@ -54,14 +54,15 @@ struct rt_mutex_waiter { struct pid *deadlock_task_pid; struct rt_mutex *deadlock_lock; #endif + int prio; }; /* - * Various helpers to access the waiters-plist: + * Various helpers to access the waiters-tree: */ static inline int rt_mutex_has_waiters(struct rt_mutex *lock) { - return !plist_head_empty(&lock->wait_list); + return !RB_EMPTY_ROOT(&lock->waiters); } static inline struct rt_mutex_waiter * @@ -69,8 +70,8 @@ rt_mutex_top_waiter(struct rt_mutex *lock) { struct rt_mutex_waiter *w; - w = plist_first_entry(&lock->wait_list, struct rt_mutex_waiter, - list_entry); + w = rb_entry(lock->waiters_leftmost, struct rt_mutex_waiter, + tree_entry); BUG_ON(w->lock != lock); return w; @@ -78,14 +79,14 @@ rt_mutex_top_waiter(struct rt_mutex *lock) static inline int task_has_pi_waiters(struct task_struct *p) { - return !plist_head_empty(&p->pi_waiters); + return !RB_EMPTY_ROOT(&p->pi_waiters); } static inline struct rt_mutex_waiter * task_top_pi_waiter(struct task_struct *p) { - return plist_first_entry(&p->pi_waiters, struct rt_mutex_waiter, - pi_list_entry); + return rb_entry(p->pi_waiters_leftmost, struct rt_mutex_waiter, + pi_tree_entry); } /* diff --git a/kernel/module.c b/kernel/module.c index f5a3b1e8ec51..d24fcf29cb64 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -815,10 +815,8 @@ SYSCALL_DEFINE2(delete_module, const char __user *, name_user, return -EFAULT; name[MODULE_NAME_LEN-1] = '\0'; - if (!(flags & O_NONBLOCK)) { - printk(KERN_WARNING - "waiting module removal not supported: please upgrade"); - } + if (!(flags & O_NONBLOCK)) + pr_warn("waiting module removal not supported: please upgrade\n"); if (mutex_lock_interruptible(&module_mutex) != 0) return -EINTR; diff --git a/kernel/padata.c b/kernel/padata.c index 2abd25d79cc8..161402f0b517 100644 --- a/kernel/padata.c +++ b/kernel/padata.c @@ -112,7 +112,7 @@ int padata_do_parallel(struct padata_instance *pinst, rcu_read_lock_bh(); - pd = rcu_dereference(pinst->pd); + pd = rcu_dereference_bh(pinst->pd); err = -EINVAL; if (!(pinst->flags & PADATA_INIT) || pinst->flags & PADATA_INVALID) diff --git a/kernel/panic.c b/kernel/panic.c index c00b4ceb39e8..6d6300375090 100644 --- a/kernel/panic.c +++ b/kernel/panic.c @@ -33,7 +33,7 @@ static int pause_on_oops; static int pause_on_oops_flag; static DEFINE_SPINLOCK(pause_on_oops_lock); -int panic_timeout; +int panic_timeout = CONFIG_PANIC_TIMEOUT; EXPORT_SYMBOL_GPL(panic_timeout); ATOMIC_NOTIFIER_HEAD(panic_notifier_list); diff --git a/kernel/params.c b/kernel/params.c index c00d5b502aa4..b00142e7f3ba 100644 --- a/kernel/params.c +++ b/kernel/params.c @@ -227,17 +227,10 @@ int parse_args(const char *doing, } /* Lazy bastard, eh? */ -#define STANDARD_PARAM_DEF(name, type, format, tmptype, strtolfn) \ +#define STANDARD_PARAM_DEF(name, type, format, strtolfn) \ int param_set_##name(const char *val, const struct kernel_param *kp) \ { \ - tmptype l; \ - int ret; \ - \ - ret = strtolfn(val, 0, &l); \ - if (ret < 0 || ((type)l != l)) \ - return ret < 0 ? ret : -EINVAL; \ - *((type *)kp->arg) = l; \ - return 0; \ + return strtolfn(val, 0, (type *)kp->arg); \ } \ int param_get_##name(char *buffer, const struct kernel_param *kp) \ { \ @@ -253,13 +246,13 @@ int parse_args(const char *doing, EXPORT_SYMBOL(param_ops_##name) -STANDARD_PARAM_DEF(byte, unsigned char, "%hhu", unsigned long, kstrtoul); -STANDARD_PARAM_DEF(short, short, "%hi", long, kstrtol); -STANDARD_PARAM_DEF(ushort, unsigned short, "%hu", unsigned long, kstrtoul); -STANDARD_PARAM_DEF(int, int, "%i", long, kstrtol); -STANDARD_PARAM_DEF(uint, unsigned int, "%u", unsigned long, kstrtoul); -STANDARD_PARAM_DEF(long, long, "%li", long, kstrtol); -STANDARD_PARAM_DEF(ulong, unsigned long, "%lu", unsigned long, kstrtoul); +STANDARD_PARAM_DEF(byte, unsigned char, "%hhu", kstrtou8); +STANDARD_PARAM_DEF(short, short, "%hi", kstrtos16); +STANDARD_PARAM_DEF(ushort, unsigned short, "%hu", kstrtou16); +STANDARD_PARAM_DEF(int, int, "%i", kstrtoint); +STANDARD_PARAM_DEF(uint, unsigned int, "%u", kstrtouint); +STANDARD_PARAM_DEF(long, long, "%li", kstrtol); +STANDARD_PARAM_DEF(ulong, unsigned long, "%lu", kstrtoul); int param_set_charp(const char *val, const struct kernel_param *kp) { diff --git a/kernel/posix-cpu-timers.c b/kernel/posix-cpu-timers.c index c7f31aa272f7..3b8946416a5f 100644 --- a/kernel/posix-cpu-timers.c +++ b/kernel/posix-cpu-timers.c @@ -233,7 +233,8 @@ void thread_group_cputimer(struct task_struct *tsk, struct task_cputime *times) /* * Sample a process (thread group) clock for the given group_leader task. - * Must be called with tasklist_lock held for reading. + * Must be called with task sighand lock held for safe while_each_thread() + * traversal. */ static int cpu_clock_sample_group(const clockid_t which_clock, struct task_struct *p, @@ -260,30 +261,53 @@ static int cpu_clock_sample_group(const clockid_t which_clock, return 0; } +static int posix_cpu_clock_get_task(struct task_struct *tsk, + const clockid_t which_clock, + struct timespec *tp) +{ + int err = -EINVAL; + unsigned long long rtn; + + if (CPUCLOCK_PERTHREAD(which_clock)) { + if (same_thread_group(tsk, current)) + err = cpu_clock_sample(which_clock, tsk, &rtn); + } else { + unsigned long flags; + struct sighand_struct *sighand; + + /* + * while_each_thread() is not yet entirely RCU safe, + * keep locking the group while sampling process + * clock for now. + */ + sighand = lock_task_sighand(tsk, &flags); + if (!sighand) + return err; + + if (tsk == current || thread_group_leader(tsk)) + err = cpu_clock_sample_group(which_clock, tsk, &rtn); + + unlock_task_sighand(tsk, &flags); + } + + if (!err) + sample_to_timespec(which_clock, rtn, tp); + + return err; +} + static int posix_cpu_clock_get(const clockid_t which_clock, struct timespec *tp) { const pid_t pid = CPUCLOCK_PID(which_clock); - int error = -EINVAL; - unsigned long long rtn; + int err = -EINVAL; if (pid == 0) { /* * Special case constant value for our own clocks. * We don't have to do any lookup to find ourselves. */ - if (CPUCLOCK_PERTHREAD(which_clock)) { - /* - * Sampling just ourselves we can do with no locking. - */ - error = cpu_clock_sample(which_clock, - current, &rtn); - } else { - read_lock(&tasklist_lock); - error = cpu_clock_sample_group(which_clock, - current, &rtn); - read_unlock(&tasklist_lock); - } + err = posix_cpu_clock_get_task(current, which_clock, tp); } else { /* * Find the given PID, and validate that the caller @@ -292,29 +316,12 @@ static int posix_cpu_clock_get(const clockid_t which_clock, struct timespec *tp) struct task_struct *p; rcu_read_lock(); p = find_task_by_vpid(pid); - if (p) { - if (CPUCLOCK_PERTHREAD(which_clock)) { - if (same_thread_group(p, current)) { - error = cpu_clock_sample(which_clock, - p, &rtn); - } - } else { - read_lock(&tasklist_lock); - if (thread_group_leader(p) && p->sighand) { - error = - cpu_clock_sample_group(which_clock, - p, &rtn); - } - read_unlock(&tasklist_lock); - } - } + if (p) + err = posix_cpu_clock_get_task(p, which_clock, tp); rcu_read_unlock(); } - if (error) - return error; - sample_to_timespec(which_clock, rtn, tp); - return 0; + return err; } @@ -371,36 +378,40 @@ static int posix_cpu_timer_create(struct k_itimer *new_timer) */ static int posix_cpu_timer_del(struct k_itimer *timer) { - struct task_struct *p = timer->it.cpu.task; int ret = 0; + unsigned long flags; + struct sighand_struct *sighand; + struct task_struct *p = timer->it.cpu.task; - if (likely(p != NULL)) { - read_lock(&tasklist_lock); - if (unlikely(p->sighand == NULL)) { - /* - * We raced with the reaping of the task. - * The deletion should have cleared us off the list. - */ - BUG_ON(!list_empty(&timer->it.cpu.entry)); - } else { - spin_lock(&p->sighand->siglock); - if (timer->it.cpu.firing) - ret = TIMER_RETRY; - else - list_del(&timer->it.cpu.entry); - spin_unlock(&p->sighand->siglock); - } - read_unlock(&tasklist_lock); + WARN_ON_ONCE(p == NULL); - if (!ret) - put_task_struct(p); + /* + * Protect against sighand release/switch in exit/exec and process/ + * thread timer list entry concurrent read/writes. + */ + sighand = lock_task_sighand(p, &flags); + if (unlikely(sighand == NULL)) { + /* + * We raced with the reaping of the task. + * The deletion should have cleared us off the list. + */ + WARN_ON_ONCE(!list_empty(&timer->it.cpu.entry)); + } else { + if (timer->it.cpu.firing) + ret = TIMER_RETRY; + else + list_del(&timer->it.cpu.entry); + + unlock_task_sighand(p, &flags); } + if (!ret) + put_task_struct(p); + return ret; } -static void cleanup_timers_list(struct list_head *head, - unsigned long long curr) +static void cleanup_timers_list(struct list_head *head) { struct cpu_timer_list *timer, *next; @@ -414,16 +425,11 @@ static void cleanup_timers_list(struct list_head *head, * time for later timer_gettime calls to return. * This must be called with the siglock held. */ -static void cleanup_timers(struct list_head *head, - cputime_t utime, cputime_t stime, - unsigned long long sum_exec_runtime) +static void cleanup_timers(struct list_head *head) { - - cputime_t ptime = utime + stime; - - cleanup_timers_list(head, cputime_to_expires(ptime)); - cleanup_timers_list(++head, cputime_to_expires(utime)); - cleanup_timers_list(++head, sum_exec_runtime); + cleanup_timers_list(head); + cleanup_timers_list(++head); + cleanup_timers_list(++head); } /* @@ -433,41 +439,14 @@ static void cleanup_timers(struct list_head *head, */ void posix_cpu_timers_exit(struct task_struct *tsk) { - cputime_t utime, stime; - add_device_randomness((const void*) &tsk->se.sum_exec_runtime, sizeof(unsigned long long)); - task_cputime(tsk, &utime, &stime); - cleanup_timers(tsk->cpu_timers, - utime, stime, tsk->se.sum_exec_runtime); + cleanup_timers(tsk->cpu_timers); } void posix_cpu_timers_exit_group(struct task_struct *tsk) { - struct signal_struct *const sig = tsk->signal; - cputime_t utime, stime; - - task_cputime(tsk, &utime, &stime); - cleanup_timers(tsk->signal->cpu_timers, - utime + sig->utime, stime + sig->stime, - tsk->se.sum_exec_runtime + sig->sum_sched_runtime); -} - -static void clear_dead_task(struct k_itimer *itimer, unsigned long long now) -{ - struct cpu_timer_list *timer = &itimer->it.cpu; - - /* - * That's all for this thread or process. - * We leave our residual in expires to be reported. - */ - put_task_struct(timer->task); - timer->task = NULL; - if (timer->expires < now) { - timer->expires = 0; - } else { - timer->expires -= now; - } + cleanup_timers(tsk->signal->cpu_timers); } static inline int expires_gt(cputime_t expires, cputime_t new_exp) @@ -477,8 +456,7 @@ static inline int expires_gt(cputime_t expires, cputime_t new_exp) /* * Insert the timer on the appropriate list before any timers that - * expire later. This must be called with the tasklist_lock held - * for reading, interrupts disabled and p->sighand->siglock taken. + * expire later. This must be called with the sighand lock held. */ static void arm_timer(struct k_itimer *timer) { @@ -569,7 +547,8 @@ static void cpu_timer_fire(struct k_itimer *timer) /* * Sample a process (thread group) timer for the given group_leader task. - * Must be called with tasklist_lock held for reading. + * Must be called with task sighand lock held for safe while_each_thread() + * traversal. */ static int cpu_timer_sample_group(const clockid_t which_clock, struct task_struct *p, @@ -608,7 +587,8 @@ static DECLARE_WORK(nohz_kick_work, nohz_kick_work_fn); */ static void posix_cpu_timer_kick_nohz(void) { - schedule_work(&nohz_kick_work); + if (context_tracking_is_enabled()) + schedule_work(&nohz_kick_work); } bool posix_cpu_timers_can_stop_tick(struct task_struct *tsk) @@ -631,43 +611,39 @@ static inline void posix_cpu_timer_kick_nohz(void) { } * If we return TIMER_RETRY, it's necessary to release the timer's lock * and try again. (This happens when the timer is in the middle of firing.) */ -static int posix_cpu_timer_set(struct k_itimer *timer, int flags, +static int posix_cpu_timer_set(struct k_itimer *timer, int timer_flags, struct itimerspec *new, struct itimerspec *old) { + unsigned long flags; + struct sighand_struct *sighand; struct task_struct *p = timer->it.cpu.task; unsigned long long old_expires, new_expires, old_incr, val; int ret; - if (unlikely(p == NULL)) { - /* - * Timer refers to a dead task's clock. - */ - return -ESRCH; - } + WARN_ON_ONCE(p == NULL); new_expires = timespec_to_sample(timer->it_clock, &new->it_value); - read_lock(&tasklist_lock); /* - * We need the tasklist_lock to protect against reaping that - * clears p->sighand. If p has just been reaped, we can no + * Protect against sighand release/switch in exit/exec and p->cpu_timers + * and p->signal->cpu_timers read/write in arm_timer() + */ + sighand = lock_task_sighand(p, &flags); + /* + * If p has just been reaped, we can no * longer get any information about it at all. */ - if (unlikely(p->sighand == NULL)) { - read_unlock(&tasklist_lock); - put_task_struct(p); - timer->it.cpu.task = NULL; + if (unlikely(sighand == NULL)) { return -ESRCH; } /* * Disarm any old timer after extracting its expiry time. */ - BUG_ON(!irqs_disabled()); + WARN_ON_ONCE(!irqs_disabled()); ret = 0; old_incr = timer->it.cpu.incr; - spin_lock(&p->sighand->siglock); old_expires = timer->it.cpu.expires; if (unlikely(timer->it.cpu.firing)) { timer->it.cpu.firing = -1; @@ -724,12 +700,11 @@ static int posix_cpu_timer_set(struct k_itimer *timer, int flags, * disable this firing since we are already reporting * it as an overrun (thanks to bump_cpu_timer above). */ - spin_unlock(&p->sighand->siglock); - read_unlock(&tasklist_lock); + unlock_task_sighand(p, &flags); goto out; } - if (new_expires != 0 && !(flags & TIMER_ABSTIME)) { + if (new_expires != 0 && !(timer_flags & TIMER_ABSTIME)) { new_expires += val; } @@ -743,9 +718,7 @@ static int posix_cpu_timer_set(struct k_itimer *timer, int flags, arm_timer(timer); } - spin_unlock(&p->sighand->siglock); - read_unlock(&tasklist_lock); - + unlock_task_sighand(p, &flags); /* * Install the new reload setting, and * set up the signal and overrun bookkeeping. @@ -787,7 +760,8 @@ static void posix_cpu_timer_get(struct k_itimer *timer, struct itimerspec *itp) { unsigned long long now; struct task_struct *p = timer->it.cpu.task; - int clear_dead; + + WARN_ON_ONCE(p == NULL); /* * Easy part: convert the reload time. @@ -800,52 +774,34 @@ static void posix_cpu_timer_get(struct k_itimer *timer, struct itimerspec *itp) return; } - if (unlikely(p == NULL)) { - /* - * This task already died and the timer will never fire. - * In this case, expires is actually the dead value. - */ - dead: - sample_to_timespec(timer->it_clock, timer->it.cpu.expires, - &itp->it_value); - return; - } - /* * Sample the clock to take the difference with the expiry time. */ if (CPUCLOCK_PERTHREAD(timer->it_clock)) { cpu_clock_sample(timer->it_clock, p, &now); - clear_dead = p->exit_state; } else { - read_lock(&tasklist_lock); - if (unlikely(p->sighand == NULL)) { + struct sighand_struct *sighand; + unsigned long flags; + + /* + * Protect against sighand release/switch in exit/exec and + * also make timer sampling safe if it ends up calling + * thread_group_cputime(). + */ + sighand = lock_task_sighand(p, &flags); + if (unlikely(sighand == NULL)) { /* * The process has been reaped. * We can't even collect a sample any more. * Call the timer disarmed, nothing else to do. */ - put_task_struct(p); - timer->it.cpu.task = NULL; timer->it.cpu.expires = 0; - read_unlock(&tasklist_lock); - goto dead; + sample_to_timespec(timer->it_clock, timer->it.cpu.expires, + &itp->it_value); } else { cpu_timer_sample_group(timer->it_clock, p, &now); - clear_dead = (unlikely(p->exit_state) && - thread_group_empty(p)); + unlock_task_sighand(p, &flags); } - read_unlock(&tasklist_lock); - } - - if (unlikely(clear_dead)) { - /* - * We've noticed that the thread is dead, but - * not yet reaped. Take this opportunity to - * drop our task ref. - */ - clear_dead_task(timer, now); - goto dead; } if (now < timer->it.cpu.expires) { @@ -1059,14 +1015,12 @@ static void check_process_timers(struct task_struct *tsk, */ void posix_cpu_timer_schedule(struct k_itimer *timer) { + struct sighand_struct *sighand; + unsigned long flags; struct task_struct *p = timer->it.cpu.task; unsigned long long now; - if (unlikely(p == NULL)) - /* - * The task was cleaned up already, no future firings. - */ - goto out; + WARN_ON_ONCE(p == NULL); /* * Fetch the current sample and update the timer's expiry time. @@ -1074,49 +1028,45 @@ void posix_cpu_timer_schedule(struct k_itimer *timer) if (CPUCLOCK_PERTHREAD(timer->it_clock)) { cpu_clock_sample(timer->it_clock, p, &now); bump_cpu_timer(timer, now); - if (unlikely(p->exit_state)) { - clear_dead_task(timer, now); + if (unlikely(p->exit_state)) + goto out; + + /* Protect timer list r/w in arm_timer() */ + sighand = lock_task_sighand(p, &flags); + if (!sighand) goto out; - } - read_lock(&tasklist_lock); /* arm_timer needs it. */ - spin_lock(&p->sighand->siglock); } else { - read_lock(&tasklist_lock); - if (unlikely(p->sighand == NULL)) { + /* + * Protect arm_timer() and timer sampling in case of call to + * thread_group_cputime(). + */ + sighand = lock_task_sighand(p, &flags); + if (unlikely(sighand == NULL)) { /* * The process has been reaped. * We can't even collect a sample any more. */ - put_task_struct(p); - timer->it.cpu.task = p = NULL; timer->it.cpu.expires = 0; - goto out_unlock; + goto out; } else if (unlikely(p->exit_state) && thread_group_empty(p)) { - /* - * We've noticed that the thread is dead, but - * not yet reaped. Take this opportunity to - * drop our task ref. - */ - cpu_timer_sample_group(timer->it_clock, p, &now); - clear_dead_task(timer, now); - goto out_unlock; + unlock_task_sighand(p, &flags); + /* Optimizations: if the process is dying, no need to rearm */ + goto out; } - spin_lock(&p->sighand->siglock); cpu_timer_sample_group(timer->it_clock, p, &now); bump_cpu_timer(timer, now); - /* Leave the tasklist_lock locked for the call below. */ + /* Leave the sighand locked for the call below. */ } /* * Now re-arm for the new expiry time. */ - BUG_ON(!irqs_disabled()); + WARN_ON_ONCE(!irqs_disabled()); arm_timer(timer); - spin_unlock(&p->sighand->siglock); - -out_unlock: - read_unlock(&tasklist_lock); + unlock_task_sighand(p, &flags); + /* Kick full dynticks CPUs in case they need to tick on the new timer */ + posix_cpu_timer_kick_nohz(); out: timer->it_overrun_last = timer->it_overrun; timer->it_overrun = -1; @@ -1200,7 +1150,7 @@ void run_posix_cpu_timers(struct task_struct *tsk) struct k_itimer *timer, *next; unsigned long flags; - BUG_ON(!irqs_disabled()); + WARN_ON_ONCE(!irqs_disabled()); /* * The fast path checks that there are no expired thread or thread @@ -1256,13 +1206,6 @@ void run_posix_cpu_timers(struct task_struct *tsk) cpu_timer_fire(timer); spin_unlock(&timer->it_lock); } - - /* - * In case some timers were rescheduled after the queue got emptied, - * wake up full dynticks CPUs. - */ - if (tsk->signal->cputimer.running) - posix_cpu_timer_kick_nohz(); } /* @@ -1274,7 +1217,7 @@ void set_process_cpu_timer(struct task_struct *tsk, unsigned int clock_idx, { unsigned long long now; - BUG_ON(clock_idx == CPUCLOCK_SCHED); + WARN_ON_ONCE(clock_idx == CPUCLOCK_SCHED); cpu_timer_sample_group(clock_idx, tsk, &now); if (oldval) { diff --git a/kernel/power/snapshot.c b/kernel/power/snapshot.c index b38109e204af..d9f61a145802 100644 --- a/kernel/power/snapshot.c +++ b/kernel/power/snapshot.c @@ -637,7 +637,7 @@ __register_nosave_region(unsigned long start_pfn, unsigned long end_pfn, BUG_ON(!region); } else /* This allocation cannot fail */ - region = alloc_bootmem(sizeof(struct nosave_region)); + region = memblock_virt_alloc(sizeof(struct nosave_region), 0); region->start_pfn = start_pfn; region->end_pfn = end_pfn; list_add_tail(®ion->list, &nosave_regions); diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c index be7c86bae576..b1d255f04135 100644 --- a/kernel/printk/printk.c +++ b/kernel/printk/printk.c @@ -757,14 +757,10 @@ void __init setup_log_buf(int early) return; if (early) { - unsigned long mem; - - mem = memblock_alloc(new_log_buf_len, PAGE_SIZE); - if (!mem) - return; - new_log_buf = __va(mem); + new_log_buf = + memblock_virt_alloc(new_log_buf_len, PAGE_SIZE); } else { - new_log_buf = alloc_bootmem_nopanic(new_log_buf_len); + new_log_buf = memblock_virt_alloc_nopanic(new_log_buf_len, 0); } if (unlikely(!new_log_buf)) { @@ -1599,10 +1595,13 @@ asmlinkage int vprintk_emit(int facility, int level, * either merge it with the current buffer and flush, or if * there was a race with interrupts (prefix == true) then just * flush it out and store this line separately. + * If the preceding printk was from a different task and missed + * a newline, flush and append the newline. */ - if (cont.len && cont.owner == current) { - if (!(lflags & LOG_PREFIX)) - stored = cont_add(facility, level, text, text_len); + if (cont.len) { + if (cont.owner == current && !(lflags & LOG_PREFIX)) + stored = cont_add(facility, level, text, + text_len); cont_flush(LOG_NEWLINE); } diff --git a/kernel/rcu/rcu.h b/kernel/rcu/rcu.h index 7859a0a3951e..79c3877e9c5b 100644 --- a/kernel/rcu/rcu.h +++ b/kernel/rcu/rcu.h @@ -96,19 +96,22 @@ static inline void debug_rcu_head_unqueue(struct rcu_head *head) } #endif /* #else !CONFIG_DEBUG_OBJECTS_RCU_HEAD */ -extern void kfree(const void *); +void kfree(const void *); static inline bool __rcu_reclaim(const char *rn, struct rcu_head *head) { unsigned long offset = (unsigned long)head->func; + rcu_lock_acquire(&rcu_callback_map); if (__is_kfree_rcu_offset(offset)) { RCU_TRACE(trace_rcu_invoke_kfree_callback(rn, head, offset)); kfree((void *)head - offset); + rcu_lock_release(&rcu_callback_map); return 1; } else { RCU_TRACE(trace_rcu_invoke_callback(rn, head)); head->func(head); + rcu_lock_release(&rcu_callback_map); return 0; } } diff --git a/kernel/rcu/srcu.c b/kernel/rcu/srcu.c index 01d5ccb8bfe3..3318d8284384 100644 --- a/kernel/rcu/srcu.c +++ b/kernel/rcu/srcu.c @@ -363,6 +363,29 @@ static void srcu_flip(struct srcu_struct *sp) /* * Enqueue an SRCU callback on the specified srcu_struct structure, * initiating grace-period processing if it is not already running. + * + * Note that all CPUs must agree that the grace period extended beyond + * all pre-existing SRCU read-side critical section. On systems with + * more than one CPU, this means that when "func()" is invoked, each CPU + * is guaranteed to have executed a full memory barrier since the end of + * its last corresponding SRCU read-side critical section whose beginning + * preceded the call to call_rcu(). It also means that each CPU executing + * an SRCU read-side critical section that continues beyond the start of + * "func()" must have executed a memory barrier after the call_rcu() + * but before the beginning of that SRCU read-side critical section. + * Note that these guarantees include CPUs that are offline, idle, or + * executing in user mode, as well as CPUs that are executing in the kernel. + * + * Furthermore, if CPU A invoked call_rcu() and CPU B invoked the + * resulting SRCU callback function "func()", then both CPU A and CPU + * B are guaranteed to execute a full memory barrier during the time + * interval between the call to call_rcu() and the invocation of "func()". + * This guarantee applies even if CPU A and CPU B are the same CPU (but + * again only if the system has more than one CPU). + * + * Of course, these guarantees apply only for invocations of call_srcu(), + * srcu_read_lock(), and srcu_read_unlock() that are all passed the same + * srcu_struct structure. */ void call_srcu(struct srcu_struct *sp, struct rcu_head *head, void (*func)(struct rcu_head *head)) @@ -459,7 +482,30 @@ static void __synchronize_srcu(struct srcu_struct *sp, int trycount) * Note that it is illegal to call synchronize_srcu() from the corresponding * SRCU read-side critical section; doing so will result in deadlock. * However, it is perfectly legal to call synchronize_srcu() on one - * srcu_struct from some other srcu_struct's read-side critical section. + * srcu_struct from some other srcu_struct's read-side critical section, + * as long as the resulting graph of srcu_structs is acyclic. + * + * There are memory-ordering constraints implied by synchronize_srcu(). + * On systems with more than one CPU, when synchronize_srcu() returns, + * each CPU is guaranteed to have executed a full memory barrier since + * the end of its last corresponding SRCU-sched read-side critical section + * whose beginning preceded the call to synchronize_srcu(). In addition, + * each CPU having an SRCU read-side critical section that extends beyond + * the return from synchronize_srcu() is guaranteed to have executed a + * full memory barrier after the beginning of synchronize_srcu() and before + * the beginning of that SRCU read-side critical section. Note that these + * guarantees include CPUs that are offline, idle, or executing in user mode, + * as well as CPUs that are executing in the kernel. + * + * Furthermore, if CPU A invoked synchronize_srcu(), which returned + * to its caller on CPU B, then both CPU A and CPU B are guaranteed + * to have executed a full memory barrier during the execution of + * synchronize_srcu(). This guarantee applies even if CPU A and CPU B + * are the same CPU, but again only if the system has more than one CPU. + * + * Of course, these memory-ordering guarantees apply only when + * synchronize_srcu(), srcu_read_lock(), and srcu_read_unlock() are + * passed the same srcu_struct structure. */ void synchronize_srcu(struct srcu_struct *sp) { @@ -476,12 +522,8 @@ EXPORT_SYMBOL_GPL(synchronize_srcu); * Wait for an SRCU grace period to elapse, but be more aggressive about * spinning rather than blocking when waiting. * - * Note that it is also illegal to call synchronize_srcu_expedited() - * from the corresponding SRCU read-side critical section; - * doing so will result in deadlock. However, it is perfectly legal - * to call synchronize_srcu_expedited() on one srcu_struct from some - * other srcu_struct's read-side critical section, as long as - * the resulting graph of srcu_structs is acyclic. + * Note that synchronize_srcu_expedited() has the same deadlock and + * memory-ordering properties as does synchronize_srcu(). */ void synchronize_srcu_expedited(struct srcu_struct *sp) { @@ -491,6 +533,7 @@ EXPORT_SYMBOL_GPL(synchronize_srcu_expedited); /** * srcu_barrier - Wait until all in-flight call_srcu() callbacks complete. + * @sp: srcu_struct on which to wait for in-flight callbacks. */ void srcu_barrier(struct srcu_struct *sp) { diff --git a/kernel/rcu/torture.c b/kernel/rcu/torture.c index 3929cd451511..732f8ae3086a 100644 --- a/kernel/rcu/torture.c +++ b/kernel/rcu/torture.c @@ -139,8 +139,6 @@ MODULE_PARM_DESC(verbose, "Enable verbose debugging printk()s"); #define VERBOSE_PRINTK_ERRSTRING(s) \ do { if (verbose) pr_alert("%s" TORTURE_FLAG "!!! " s "\n", torture_type); } while (0) -static char printk_buf[4096]; - static int nrealreaders; static struct task_struct *writer_task; static struct task_struct **fakewriter_tasks; @@ -376,7 +374,7 @@ struct rcu_torture_ops { void (*call)(struct rcu_head *head, void (*func)(struct rcu_head *rcu)); void (*cb_barrier)(void); void (*fqs)(void); - int (*stats)(char *page); + void (*stats)(char *page); int irq_capable; int can_boost; const char *name; @@ -578,21 +576,19 @@ static void srcu_torture_barrier(void) srcu_barrier(&srcu_ctl); } -static int srcu_torture_stats(char *page) +static void srcu_torture_stats(char *page) { - int cnt = 0; int cpu; int idx = srcu_ctl.completed & 0x1; - cnt += sprintf(&page[cnt], "%s%s per-CPU(idx=%d):", + page += sprintf(page, "%s%s per-CPU(idx=%d):", torture_type, TORTURE_FLAG, idx); for_each_possible_cpu(cpu) { - cnt += sprintf(&page[cnt], " %d(%lu,%lu)", cpu, + page += sprintf(page, " %d(%lu,%lu)", cpu, per_cpu_ptr(srcu_ctl.per_cpu_ref, cpu)->c[!idx], per_cpu_ptr(srcu_ctl.per_cpu_ref, cpu)->c[idx]); } - cnt += sprintf(&page[cnt], "\n"); - return cnt; + sprintf(page, "\n"); } static void srcu_torture_synchronize_expedited(void) @@ -1052,10 +1048,9 @@ rcu_torture_reader(void *arg) /* * Create an RCU-torture statistics message in the specified buffer. */ -static int +static void rcu_torture_printk(char *page) { - int cnt = 0; int cpu; int i; long pipesummary[RCU_TORTURE_PIPE_LEN + 1] = { 0 }; @@ -1071,8 +1066,8 @@ rcu_torture_printk(char *page) if (pipesummary[i] != 0) break; } - cnt += sprintf(&page[cnt], "%s%s ", torture_type, TORTURE_FLAG); - cnt += sprintf(&page[cnt], + page += sprintf(page, "%s%s ", torture_type, TORTURE_FLAG); + page += sprintf(page, "rtc: %p ver: %lu tfle: %d rta: %d rtaf: %d rtf: %d ", rcu_torture_current, rcu_torture_current_version, @@ -1080,53 +1075,52 @@ rcu_torture_printk(char *page) atomic_read(&n_rcu_torture_alloc), atomic_read(&n_rcu_torture_alloc_fail), atomic_read(&n_rcu_torture_free)); - cnt += sprintf(&page[cnt], "rtmbe: %d rtbke: %ld rtbre: %ld ", + page += sprintf(page, "rtmbe: %d rtbke: %ld rtbre: %ld ", atomic_read(&n_rcu_torture_mberror), n_rcu_torture_boost_ktrerror, n_rcu_torture_boost_rterror); - cnt += sprintf(&page[cnt], "rtbf: %ld rtb: %ld nt: %ld ", + page += sprintf(page, "rtbf: %ld rtb: %ld nt: %ld ", n_rcu_torture_boost_failure, n_rcu_torture_boosts, n_rcu_torture_timers); - cnt += sprintf(&page[cnt], + page += sprintf(page, "onoff: %ld/%ld:%ld/%ld %d,%d:%d,%d %lu:%lu (HZ=%d) ", n_online_successes, n_online_attempts, n_offline_successes, n_offline_attempts, min_online, max_online, min_offline, max_offline, sum_online, sum_offline, HZ); - cnt += sprintf(&page[cnt], "barrier: %ld/%ld:%ld", + page += sprintf(page, "barrier: %ld/%ld:%ld", n_barrier_successes, n_barrier_attempts, n_rcu_torture_barrier_error); - cnt += sprintf(&page[cnt], "\n%s%s ", torture_type, TORTURE_FLAG); + page += sprintf(page, "\n%s%s ", torture_type, TORTURE_FLAG); if (atomic_read(&n_rcu_torture_mberror) != 0 || n_rcu_torture_barrier_error != 0 || n_rcu_torture_boost_ktrerror != 0 || n_rcu_torture_boost_rterror != 0 || n_rcu_torture_boost_failure != 0 || i > 1) { - cnt += sprintf(&page[cnt], "!!! "); + page += sprintf(page, "!!! "); atomic_inc(&n_rcu_torture_error); WARN_ON_ONCE(1); } - cnt += sprintf(&page[cnt], "Reader Pipe: "); + page += sprintf(page, "Reader Pipe: "); for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++) - cnt += sprintf(&page[cnt], " %ld", pipesummary[i]); - cnt += sprintf(&page[cnt], "\n%s%s ", torture_type, TORTURE_FLAG); - cnt += sprintf(&page[cnt], "Reader Batch: "); + page += sprintf(page, " %ld", pipesummary[i]); + page += sprintf(page, "\n%s%s ", torture_type, TORTURE_FLAG); + page += sprintf(page, "Reader Batch: "); for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++) - cnt += sprintf(&page[cnt], " %ld", batchsummary[i]); - cnt += sprintf(&page[cnt], "\n%s%s ", torture_type, TORTURE_FLAG); - cnt += sprintf(&page[cnt], "Free-Block Circulation: "); + page += sprintf(page, " %ld", batchsummary[i]); + page += sprintf(page, "\n%s%s ", torture_type, TORTURE_FLAG); + page += sprintf(page, "Free-Block Circulation: "); for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++) { - cnt += sprintf(&page[cnt], " %d", + page += sprintf(page, " %d", atomic_read(&rcu_torture_wcount[i])); } - cnt += sprintf(&page[cnt], "\n"); + page += sprintf(page, "\n"); if (cur_ops->stats) - cnt += cur_ops->stats(&page[cnt]); - return cnt; + cur_ops->stats(page); } /* @@ -1140,10 +1134,17 @@ rcu_torture_printk(char *page) static void rcu_torture_stats_print(void) { - int cnt; + int size = nr_cpu_ids * 200 + 8192; + char *buf; - cnt = rcu_torture_printk(printk_buf); - pr_alert("%s", printk_buf); + buf = kmalloc(size, GFP_KERNEL); + if (!buf) { + pr_err("rcu-torture: Out of memory, need: %d", size); + return; + } + rcu_torture_printk(buf); + pr_alert("%s", buf); + kfree(buf); } /* @@ -1578,6 +1579,7 @@ static int rcu_torture_barrier_cbs(void *arg) { long myid = (long)arg; bool lastphase = 0; + bool newphase; struct rcu_head rcu; init_rcu_head_on_stack(&rcu); @@ -1585,10 +1587,11 @@ static int rcu_torture_barrier_cbs(void *arg) set_user_nice(current, 19); do { wait_event(barrier_cbs_wq[myid], - barrier_phase != lastphase || + (newphase = + ACCESS_ONCE(barrier_phase)) != lastphase || kthread_should_stop() || fullstop != FULLSTOP_DONTSTOP); - lastphase = barrier_phase; + lastphase = newphase; smp_mb(); /* ensure barrier_phase load before ->call(). */ if (kthread_should_stop() || fullstop != FULLSTOP_DONTSTOP) break; @@ -1625,7 +1628,7 @@ static int rcu_torture_barrier(void *arg) if (kthread_should_stop() || fullstop != FULLSTOP_DONTSTOP) break; n_barrier_attempts++; - cur_ops->cb_barrier(); + cur_ops->cb_barrier(); /* Implies smp_mb() for wait_event(). */ if (atomic_read(&barrier_cbs_invoked) != n_barrier_cbs) { n_rcu_torture_barrier_error++; WARN_ON_ONCE(1); diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c index dd081987a8ec..b3d116cd072d 100644 --- a/kernel/rcu/tree.c +++ b/kernel/rcu/tree.c @@ -369,6 +369,9 @@ static struct rcu_node *rcu_get_root(struct rcu_state *rsp) static void rcu_eqs_enter_common(struct rcu_dynticks *rdtp, long long oldval, bool user) { + struct rcu_state *rsp; + struct rcu_data *rdp; + trace_rcu_dyntick(TPS("Start"), oldval, rdtp->dynticks_nesting); if (!user && !is_idle_task(current)) { struct task_struct *idle __maybe_unused = @@ -380,6 +383,10 @@ static void rcu_eqs_enter_common(struct rcu_dynticks *rdtp, long long oldval, current->pid, current->comm, idle->pid, idle->comm); /* must be idle task! */ } + for_each_rcu_flavor(rsp) { + rdp = this_cpu_ptr(rsp->rda); + do_nocb_deferred_wakeup(rdp); + } rcu_prepare_for_idle(smp_processor_id()); /* CPUs seeing atomic_inc() must see prior RCU read-side crit sects */ smp_mb__before_atomic_inc(); /* See above. */ @@ -411,11 +418,12 @@ static void rcu_eqs_enter(bool user) rdtp = this_cpu_ptr(&rcu_dynticks); oldval = rdtp->dynticks_nesting; WARN_ON_ONCE((oldval & DYNTICK_TASK_NEST_MASK) == 0); - if ((oldval & DYNTICK_TASK_NEST_MASK) == DYNTICK_TASK_NEST_VALUE) + if ((oldval & DYNTICK_TASK_NEST_MASK) == DYNTICK_TASK_NEST_VALUE) { rdtp->dynticks_nesting = 0; - else + rcu_eqs_enter_common(rdtp, oldval, user); + } else { rdtp->dynticks_nesting -= DYNTICK_TASK_NEST_VALUE; - rcu_eqs_enter_common(rdtp, oldval, user); + } } /** @@ -533,11 +541,12 @@ static void rcu_eqs_exit(bool user) rdtp = this_cpu_ptr(&rcu_dynticks); oldval = rdtp->dynticks_nesting; WARN_ON_ONCE(oldval < 0); - if (oldval & DYNTICK_TASK_NEST_MASK) + if (oldval & DYNTICK_TASK_NEST_MASK) { rdtp->dynticks_nesting += DYNTICK_TASK_NEST_VALUE; - else + } else { rdtp->dynticks_nesting = DYNTICK_TASK_EXIT_IDLE; - rcu_eqs_exit_common(rdtp, oldval, user); + rcu_eqs_exit_common(rdtp, oldval, user); + } } /** @@ -716,7 +725,7 @@ bool rcu_lockdep_current_cpu_online(void) bool ret; if (in_nmi()) - return 1; + return true; preempt_disable(); rdp = this_cpu_ptr(&rcu_sched_data); rnp = rdp->mynode; @@ -755,6 +764,12 @@ static int dyntick_save_progress_counter(struct rcu_data *rdp, } /* + * This function really isn't for public consumption, but RCU is special in + * that context switches can allow the state machine to make progress. + */ +extern void resched_cpu(int cpu); + +/* * Return true if the specified CPU has passed through a quiescent * state by virtue of being in or having passed through an dynticks * idle state since the last call to dyntick_save_progress_counter() @@ -812,16 +827,34 @@ static int rcu_implicit_dynticks_qs(struct rcu_data *rdp, */ rcu_kick_nohz_cpu(rdp->cpu); + /* + * Alternatively, the CPU might be running in the kernel + * for an extended period of time without a quiescent state. + * Attempt to force the CPU through the scheduler to gain the + * needed quiescent state, but only if the grace period has gone + * on for an uncommonly long time. If there are many stuck CPUs, + * we will beat on the first one until it gets unstuck, then move + * to the next. Only do this for the primary flavor of RCU. + */ + if (rdp->rsp == rcu_state && + ULONG_CMP_GE(ACCESS_ONCE(jiffies), rdp->rsp->jiffies_resched)) { + rdp->rsp->jiffies_resched += 5; + resched_cpu(rdp->cpu); + } + return 0; } static void record_gp_stall_check_time(struct rcu_state *rsp) { unsigned long j = ACCESS_ONCE(jiffies); + unsigned long j1; rsp->gp_start = j; smp_wmb(); /* Record start time before stall time. */ - rsp->jiffies_stall = j + rcu_jiffies_till_stall_check(); + j1 = rcu_jiffies_till_stall_check(); + rsp->jiffies_stall = j + j1; + rsp->jiffies_resched = j + j1 / 2; } /* @@ -1133,8 +1166,10 @@ rcu_start_future_gp(struct rcu_node *rnp, struct rcu_data *rdp) * hold it, acquire the root rcu_node structure's lock in order to * start one (if needed). */ - if (rnp != rnp_root) + if (rnp != rnp_root) { raw_spin_lock(&rnp_root->lock); + smp_mb__after_unlock_lock(); + } /* * Get a new grace-period number. If there really is no grace @@ -1354,6 +1389,7 @@ static void note_gp_changes(struct rcu_state *rsp, struct rcu_data *rdp) local_irq_restore(flags); return; } + smp_mb__after_unlock_lock(); __note_gp_changes(rsp, rnp, rdp); raw_spin_unlock_irqrestore(&rnp->lock, flags); } @@ -1368,6 +1404,7 @@ static int rcu_gp_init(struct rcu_state *rsp) rcu_bind_gp_kthread(); raw_spin_lock_irq(&rnp->lock); + smp_mb__after_unlock_lock(); if (rsp->gp_flags == 0) { /* Spurious wakeup, tell caller to go back to sleep. */ raw_spin_unlock_irq(&rnp->lock); @@ -1409,6 +1446,7 @@ static int rcu_gp_init(struct rcu_state *rsp) */ rcu_for_each_node_breadth_first(rsp, rnp) { raw_spin_lock_irq(&rnp->lock); + smp_mb__after_unlock_lock(); rdp = this_cpu_ptr(rsp->rda); rcu_preempt_check_blocked_tasks(rnp); rnp->qsmask = rnp->qsmaskinit; @@ -1463,6 +1501,7 @@ static int rcu_gp_fqs(struct rcu_state *rsp, int fqs_state_in) /* Clear flag to prevent immediate re-entry. */ if (ACCESS_ONCE(rsp->gp_flags) & RCU_GP_FLAG_FQS) { raw_spin_lock_irq(&rnp->lock); + smp_mb__after_unlock_lock(); rsp->gp_flags &= ~RCU_GP_FLAG_FQS; raw_spin_unlock_irq(&rnp->lock); } @@ -1480,6 +1519,7 @@ static void rcu_gp_cleanup(struct rcu_state *rsp) struct rcu_node *rnp = rcu_get_root(rsp); raw_spin_lock_irq(&rnp->lock); + smp_mb__after_unlock_lock(); gp_duration = jiffies - rsp->gp_start; if (gp_duration > rsp->gp_max) rsp->gp_max = gp_duration; @@ -1505,16 +1545,19 @@ static void rcu_gp_cleanup(struct rcu_state *rsp) */ rcu_for_each_node_breadth_first(rsp, rnp) { raw_spin_lock_irq(&rnp->lock); + smp_mb__after_unlock_lock(); ACCESS_ONCE(rnp->completed) = rsp->gpnum; rdp = this_cpu_ptr(rsp->rda); if (rnp == rdp->mynode) __note_gp_changes(rsp, rnp, rdp); + /* smp_mb() provided by prior unlock-lock pair. */ nocb += rcu_future_gp_cleanup(rsp, rnp); raw_spin_unlock_irq(&rnp->lock); cond_resched(); } rnp = rcu_get_root(rsp); raw_spin_lock_irq(&rnp->lock); + smp_mb__after_unlock_lock(); rcu_nocb_gp_set(rnp, nocb); rsp->completed = rsp->gpnum; /* Declare grace period done. */ @@ -1553,6 +1596,7 @@ static int __noreturn rcu_gp_kthread(void *arg) wait_event_interruptible(rsp->gp_wq, ACCESS_ONCE(rsp->gp_flags) & RCU_GP_FLAG_INIT); + /* Locking provides needed memory barrier. */ if (rcu_gp_init(rsp)) break; cond_resched(); @@ -1582,6 +1626,7 @@ static int __noreturn rcu_gp_kthread(void *arg) (!ACCESS_ONCE(rnp->qsmask) && !rcu_preempt_blocked_readers_cgp(rnp)), j); + /* Locking provides needed memory barriers. */ /* If grace period done, leave loop. */ if (!ACCESS_ONCE(rnp->qsmask) && !rcu_preempt_blocked_readers_cgp(rnp)) @@ -1749,6 +1794,7 @@ rcu_report_qs_rnp(unsigned long mask, struct rcu_state *rsp, rnp_c = rnp; rnp = rnp->parent; raw_spin_lock_irqsave(&rnp->lock, flags); + smp_mb__after_unlock_lock(); WARN_ON_ONCE(rnp_c->qsmask); } @@ -1778,6 +1824,7 @@ rcu_report_qs_rdp(int cpu, struct rcu_state *rsp, struct rcu_data *rdp) rnp = rdp->mynode; raw_spin_lock_irqsave(&rnp->lock, flags); + smp_mb__after_unlock_lock(); if (rdp->passed_quiesce == 0 || rdp->gpnum != rnp->gpnum || rnp->completed == rnp->gpnum) { @@ -1901,13 +1948,13 @@ rcu_send_cbs_to_orphanage(int cpu, struct rcu_state *rsp, * Adopt the RCU callbacks from the specified rcu_state structure's * orphanage. The caller must hold the ->orphan_lock. */ -static void rcu_adopt_orphan_cbs(struct rcu_state *rsp) +static void rcu_adopt_orphan_cbs(struct rcu_state *rsp, unsigned long flags) { int i; struct rcu_data *rdp = __this_cpu_ptr(rsp->rda); /* No-CBs CPUs are handled specially. */ - if (rcu_nocb_adopt_orphan_cbs(rsp, rdp)) + if (rcu_nocb_adopt_orphan_cbs(rsp, rdp, flags)) return; /* Do the accounting first. */ @@ -1986,12 +2033,13 @@ static void rcu_cleanup_dead_cpu(int cpu, struct rcu_state *rsp) /* Orphan the dead CPU's callbacks, and adopt them if appropriate. */ rcu_send_cbs_to_orphanage(cpu, rsp, rnp, rdp); - rcu_adopt_orphan_cbs(rsp); + rcu_adopt_orphan_cbs(rsp, flags); /* Remove the outgoing CPU from the masks in the rcu_node hierarchy. */ mask = rdp->grpmask; /* rnp->grplo is constant. */ do { raw_spin_lock(&rnp->lock); /* irqs already disabled. */ + smp_mb__after_unlock_lock(); rnp->qsmaskinit &= ~mask; if (rnp->qsmaskinit != 0) { if (rnp != rdp->mynode) @@ -2202,6 +2250,7 @@ static void force_qs_rnp(struct rcu_state *rsp, cond_resched(); mask = 0; raw_spin_lock_irqsave(&rnp->lock, flags); + smp_mb__after_unlock_lock(); if (!rcu_gp_in_progress(rsp)) { raw_spin_unlock_irqrestore(&rnp->lock, flags); return; @@ -2231,6 +2280,7 @@ static void force_qs_rnp(struct rcu_state *rsp, rnp = rcu_get_root(rsp); if (rnp->qsmask == 0) { raw_spin_lock_irqsave(&rnp->lock, flags); + smp_mb__after_unlock_lock(); rcu_initiate_boost(rnp, flags); /* releases rnp->lock. */ } } @@ -2263,6 +2313,7 @@ static void force_quiescent_state(struct rcu_state *rsp) /* Reached the root of the rcu_node tree, acquire lock. */ raw_spin_lock_irqsave(&rnp_old->lock, flags); + smp_mb__after_unlock_lock(); raw_spin_unlock(&rnp_old->fqslock); if (ACCESS_ONCE(rsp->gp_flags) & RCU_GP_FLAG_FQS) { rsp->n_force_qs_lh++; @@ -2303,6 +2354,9 @@ __rcu_process_callbacks(struct rcu_state *rsp) /* If there are callbacks ready, invoke them. */ if (cpu_has_callbacks_ready_to_invoke(rdp)) invoke_rcu_callbacks(rsp, rdp); + + /* Do any needed deferred wakeups of rcuo kthreads. */ + do_nocb_deferred_wakeup(rdp); } /* @@ -2378,6 +2432,7 @@ static void __call_rcu_core(struct rcu_state *rsp, struct rcu_data *rdp, struct rcu_node *rnp_root = rcu_get_root(rsp); raw_spin_lock(&rnp_root->lock); + smp_mb__after_unlock_lock(); rcu_start_gp(rsp); raw_spin_unlock(&rnp_root->lock); } else { @@ -2437,7 +2492,7 @@ __call_rcu(struct rcu_head *head, void (*func)(struct rcu_head *rcu), if (cpu != -1) rdp = per_cpu_ptr(rsp->rda, cpu); - offline = !__call_rcu_nocb(rdp, head, lazy); + offline = !__call_rcu_nocb(rdp, head, lazy, flags); WARN_ON_ONCE(offline); /* _call_rcu() is illegal on offline CPU; leak the callback. */ local_irq_restore(flags); @@ -2757,6 +2812,10 @@ static int __rcu_pending(struct rcu_state *rsp, struct rcu_data *rdp) /* Check for CPU stalls, if enabled. */ check_cpu_stall(rsp, rdp); + /* Is this CPU a NO_HZ_FULL CPU that should ignore RCU? */ + if (rcu_nohz_full_cpu(rsp)) + return 0; + /* Is the RCU core waiting for a quiescent state from this CPU? */ if (rcu_scheduler_fully_active && rdp->qs_pending && !rdp->passed_quiesce) { @@ -2790,6 +2849,12 @@ static int __rcu_pending(struct rcu_state *rsp, struct rcu_data *rdp) return 1; } + /* Does this CPU need a deferred NOCB wakeup? */ + if (rcu_nocb_need_deferred_wakeup(rdp)) { + rdp->n_rp_nocb_defer_wakeup++; + return 1; + } + /* nothing to do */ rdp->n_rp_need_nothing++; return 0; @@ -3214,9 +3279,9 @@ static void __init rcu_init_levelspread(struct rcu_state *rsp) { int i; - for (i = rcu_num_lvls - 1; i > 0; i--) + rsp->levelspread[rcu_num_lvls - 1] = rcu_fanout_leaf; + for (i = rcu_num_lvls - 2; i >= 0; i--) rsp->levelspread[i] = CONFIG_RCU_FANOUT; - rsp->levelspread[0] = rcu_fanout_leaf; } #else /* #ifdef CONFIG_RCU_FANOUT_EXACT */ static void __init rcu_init_levelspread(struct rcu_state *rsp) @@ -3346,6 +3411,8 @@ static void __init rcu_init_geometry(void) if (rcu_fanout_leaf == CONFIG_RCU_FANOUT_LEAF && nr_cpu_ids == NR_CPUS) return; + pr_info("RCU: Adjusting geometry for rcu_fanout_leaf=%d, nr_cpu_ids=%d\n", + rcu_fanout_leaf, nr_cpu_ids); /* * Compute number of nodes that can be handled an rcu_node tree diff --git a/kernel/rcu/tree.h b/kernel/rcu/tree.h index 52be957c9fe2..8c19873f1ac9 100644 --- a/kernel/rcu/tree.h +++ b/kernel/rcu/tree.h @@ -317,6 +317,7 @@ struct rcu_data { unsigned long n_rp_cpu_needs_gp; unsigned long n_rp_gp_completed; unsigned long n_rp_gp_started; + unsigned long n_rp_nocb_defer_wakeup; unsigned long n_rp_need_nothing; /* 6) _rcu_barrier() and OOM callbacks. */ @@ -335,6 +336,7 @@ struct rcu_data { int nocb_p_count_lazy; /* (approximate). */ wait_queue_head_t nocb_wq; /* For nocb kthreads to sleep on. */ struct task_struct *nocb_kthread; + bool nocb_defer_wakeup; /* Defer wakeup of nocb_kthread. */ #endif /* #ifdef CONFIG_RCU_NOCB_CPU */ /* 8) RCU CPU stall data. */ @@ -453,6 +455,8 @@ struct rcu_state { /* but in jiffies. */ unsigned long jiffies_stall; /* Time at which to check */ /* for CPU stalls. */ + unsigned long jiffies_resched; /* Time at which to resched */ + /* a reluctant CPU. */ unsigned long gp_max; /* Maximum GP duration in */ /* jiffies. */ const char *name; /* Name of structure. */ @@ -548,9 +552,12 @@ static void rcu_nocb_gp_set(struct rcu_node *rnp, int nrq); static void rcu_nocb_gp_cleanup(struct rcu_state *rsp, struct rcu_node *rnp); static void rcu_init_one_nocb(struct rcu_node *rnp); static bool __call_rcu_nocb(struct rcu_data *rdp, struct rcu_head *rhp, - bool lazy); + bool lazy, unsigned long flags); static bool rcu_nocb_adopt_orphan_cbs(struct rcu_state *rsp, - struct rcu_data *rdp); + struct rcu_data *rdp, + unsigned long flags); +static bool rcu_nocb_need_deferred_wakeup(struct rcu_data *rdp); +static void do_nocb_deferred_wakeup(struct rcu_data *rdp); static void rcu_boot_init_nocb_percpu_data(struct rcu_data *rdp); static void rcu_spawn_nocb_kthreads(struct rcu_state *rsp); static void rcu_kick_nohz_cpu(int cpu); @@ -564,6 +571,7 @@ static void rcu_sysidle_report_gp(struct rcu_state *rsp, int isidle, unsigned long maxj); static void rcu_bind_gp_kthread(void); static void rcu_sysidle_init_percpu_data(struct rcu_dynticks *rdtp); +static bool rcu_nohz_full_cpu(struct rcu_state *rsp); #endif /* #ifndef RCU_TREE_NONCORE */ diff --git a/kernel/rcu/tree_plugin.h b/kernel/rcu/tree_plugin.h index 08a765232432..6e2ef4b2b920 100644 --- a/kernel/rcu/tree_plugin.h +++ b/kernel/rcu/tree_plugin.h @@ -204,6 +204,7 @@ static void rcu_preempt_note_context_switch(int cpu) rdp = per_cpu_ptr(rcu_preempt_state.rda, cpu); rnp = rdp->mynode; raw_spin_lock_irqsave(&rnp->lock, flags); + smp_mb__after_unlock_lock(); t->rcu_read_unlock_special |= RCU_READ_UNLOCK_BLOCKED; t->rcu_blocked_node = rnp; @@ -312,6 +313,7 @@ static void rcu_report_unblock_qs_rnp(struct rcu_node *rnp, unsigned long flags) mask = rnp->grpmask; raw_spin_unlock(&rnp->lock); /* irqs remain disabled. */ raw_spin_lock(&rnp_p->lock); /* irqs already disabled. */ + smp_mb__after_unlock_lock(); rcu_report_qs_rnp(mask, &rcu_preempt_state, rnp_p, flags); } @@ -361,10 +363,14 @@ void rcu_read_unlock_special(struct task_struct *t) special = t->rcu_read_unlock_special; if (special & RCU_READ_UNLOCK_NEED_QS) { rcu_preempt_qs(smp_processor_id()); + if (!t->rcu_read_unlock_special) { + local_irq_restore(flags); + return; + } } - /* Hardware IRQ handlers cannot block. */ - if (in_irq() || in_serving_softirq()) { + /* Hardware IRQ handlers cannot block, complain if they get here. */ + if (WARN_ON_ONCE(in_irq() || in_serving_softirq())) { local_irq_restore(flags); return; } @@ -381,6 +387,7 @@ void rcu_read_unlock_special(struct task_struct *t) for (;;) { rnp = t->rcu_blocked_node; raw_spin_lock(&rnp->lock); /* irqs already disabled. */ + smp_mb__after_unlock_lock(); if (rnp == t->rcu_blocked_node) break; raw_spin_unlock(&rnp->lock); /* irqs remain disabled. */ @@ -605,6 +612,7 @@ static int rcu_preempt_offline_tasks(struct rcu_state *rsp, while (!list_empty(lp)) { t = list_entry(lp->next, typeof(*t), rcu_node_entry); raw_spin_lock(&rnp_root->lock); /* irqs already disabled */ + smp_mb__after_unlock_lock(); list_del(&t->rcu_node_entry); t->rcu_blocked_node = rnp_root; list_add(&t->rcu_node_entry, lp_root); @@ -629,6 +637,7 @@ static int rcu_preempt_offline_tasks(struct rcu_state *rsp, * in this case. */ raw_spin_lock(&rnp_root->lock); /* irqs already disabled */ + smp_mb__after_unlock_lock(); if (rnp_root->boost_tasks != NULL && rnp_root->boost_tasks != rnp_root->gp_tasks && rnp_root->boost_tasks != rnp_root->exp_tasks) @@ -772,6 +781,7 @@ static void rcu_report_exp_rnp(struct rcu_state *rsp, struct rcu_node *rnp, unsigned long mask; raw_spin_lock_irqsave(&rnp->lock, flags); + smp_mb__after_unlock_lock(); for (;;) { if (!sync_rcu_preempt_exp_done(rnp)) { raw_spin_unlock_irqrestore(&rnp->lock, flags); @@ -779,14 +789,17 @@ static void rcu_report_exp_rnp(struct rcu_state *rsp, struct rcu_node *rnp, } if (rnp->parent == NULL) { raw_spin_unlock_irqrestore(&rnp->lock, flags); - if (wake) + if (wake) { + smp_mb(); /* EGP done before wake_up(). */ wake_up(&sync_rcu_preempt_exp_wq); + } break; } mask = rnp->grpmask; raw_spin_unlock(&rnp->lock); /* irqs remain disabled */ rnp = rnp->parent; raw_spin_lock(&rnp->lock); /* irqs already disabled */ + smp_mb__after_unlock_lock(); rnp->expmask &= ~mask; } } @@ -806,6 +819,7 @@ sync_rcu_preempt_exp_init(struct rcu_state *rsp, struct rcu_node *rnp) int must_wait = 0; raw_spin_lock_irqsave(&rnp->lock, flags); + smp_mb__after_unlock_lock(); if (list_empty(&rnp->blkd_tasks)) { raw_spin_unlock_irqrestore(&rnp->lock, flags); } else { @@ -886,6 +900,7 @@ void synchronize_rcu_expedited(void) /* Initialize ->expmask for all non-leaf rcu_node structures. */ rcu_for_each_nonleaf_node_breadth_first(rsp, rnp) { raw_spin_lock_irqsave(&rnp->lock, flags); + smp_mb__after_unlock_lock(); rnp->expmask = rnp->qsmaskinit; raw_spin_unlock_irqrestore(&rnp->lock, flags); } @@ -1191,6 +1206,7 @@ static int rcu_boost(struct rcu_node *rnp) return 0; /* Nothing left to boost. */ raw_spin_lock_irqsave(&rnp->lock, flags); + smp_mb__after_unlock_lock(); /* * Recheck under the lock: all tasks in need of boosting @@ -1377,6 +1393,7 @@ static int rcu_spawn_one_boost_kthread(struct rcu_state *rsp, if (IS_ERR(t)) return PTR_ERR(t); raw_spin_lock_irqsave(&rnp->lock, flags); + smp_mb__after_unlock_lock(); rnp->boost_kthread_task = t; raw_spin_unlock_irqrestore(&rnp->lock, flags); sp.sched_priority = RCU_BOOST_PRIO; @@ -1769,6 +1786,7 @@ static void rcu_prepare_for_idle(int cpu) continue; rnp = rdp->mynode; raw_spin_lock(&rnp->lock); /* irqs already disabled. */ + smp_mb__after_unlock_lock(); rcu_accelerate_cbs(rsp, rnp, rdp); raw_spin_unlock(&rnp->lock); /* irqs remain disabled. */ } @@ -1852,6 +1870,7 @@ static int rcu_oom_notify(struct notifier_block *self, /* Wait for callbacks from earlier instance to complete. */ wait_event(oom_callback_wq, atomic_read(&oom_callback_count) == 0); + smp_mb(); /* Ensure callback reuse happens after callback invocation. */ /* * Prevent premature wakeup: ensure that all increments happen @@ -2101,7 +2120,8 @@ bool rcu_is_nocb_cpu(int cpu) static void __call_rcu_nocb_enqueue(struct rcu_data *rdp, struct rcu_head *rhp, struct rcu_head **rhtp, - int rhcount, int rhcount_lazy) + int rhcount, int rhcount_lazy, + unsigned long flags) { int len; struct rcu_head **old_rhpp; @@ -2122,9 +2142,16 @@ static void __call_rcu_nocb_enqueue(struct rcu_data *rdp, } len = atomic_long_read(&rdp->nocb_q_count); if (old_rhpp == &rdp->nocb_head) { - wake_up(&rdp->nocb_wq); /* ... only if queue was empty ... */ + if (!irqs_disabled_flags(flags)) { + wake_up(&rdp->nocb_wq); /* ... if queue was empty ... */ + trace_rcu_nocb_wake(rdp->rsp->name, rdp->cpu, + TPS("WakeEmpty")); + } else { + rdp->nocb_defer_wakeup = true; + trace_rcu_nocb_wake(rdp->rsp->name, rdp->cpu, + TPS("WakeEmptyIsDeferred")); + } rdp->qlen_last_fqs_check = 0; - trace_rcu_nocb_wake(rdp->rsp->name, rdp->cpu, TPS("WakeEmpty")); } else if (len > rdp->qlen_last_fqs_check + qhimark) { wake_up_process(t); /* ... or if many callbacks queued. */ rdp->qlen_last_fqs_check = LONG_MAX / 2; @@ -2145,12 +2172,12 @@ static void __call_rcu_nocb_enqueue(struct rcu_data *rdp, * "rcuo" kthread can find it. */ static bool __call_rcu_nocb(struct rcu_data *rdp, struct rcu_head *rhp, - bool lazy) + bool lazy, unsigned long flags) { if (!rcu_is_nocb_cpu(rdp->cpu)) return 0; - __call_rcu_nocb_enqueue(rdp, rhp, &rhp->next, 1, lazy); + __call_rcu_nocb_enqueue(rdp, rhp, &rhp->next, 1, lazy, flags); if (__is_kfree_rcu_offset((unsigned long)rhp->func)) trace_rcu_kfree_callback(rdp->rsp->name, rhp, (unsigned long)rhp->func, @@ -2168,7 +2195,8 @@ static bool __call_rcu_nocb(struct rcu_data *rdp, struct rcu_head *rhp, * not a no-CBs CPU. */ static bool __maybe_unused rcu_nocb_adopt_orphan_cbs(struct rcu_state *rsp, - struct rcu_data *rdp) + struct rcu_data *rdp, + unsigned long flags) { long ql = rsp->qlen; long qll = rsp->qlen_lazy; @@ -2182,14 +2210,14 @@ static bool __maybe_unused rcu_nocb_adopt_orphan_cbs(struct rcu_state *rsp, /* First, enqueue the donelist, if any. This preserves CB ordering. */ if (rsp->orphan_donelist != NULL) { __call_rcu_nocb_enqueue(rdp, rsp->orphan_donelist, - rsp->orphan_donetail, ql, qll); + rsp->orphan_donetail, ql, qll, flags); ql = qll = 0; rsp->orphan_donelist = NULL; rsp->orphan_donetail = &rsp->orphan_donelist; } if (rsp->orphan_nxtlist != NULL) { __call_rcu_nocb_enqueue(rdp, rsp->orphan_nxtlist, - rsp->orphan_nxttail, ql, qll); + rsp->orphan_nxttail, ql, qll, flags); ql = qll = 0; rsp->orphan_nxtlist = NULL; rsp->orphan_nxttail = &rsp->orphan_nxtlist; @@ -2209,6 +2237,7 @@ static void rcu_nocb_wait_gp(struct rcu_data *rdp) struct rcu_node *rnp = rdp->mynode; raw_spin_lock_irqsave(&rnp->lock, flags); + smp_mb__after_unlock_lock(); c = rcu_start_future_gp(rnp, rdp); raw_spin_unlock_irqrestore(&rnp->lock, flags); @@ -2250,6 +2279,7 @@ static int rcu_nocb_kthread(void *arg) trace_rcu_nocb_wake(rdp->rsp->name, rdp->cpu, TPS("Sleep")); wait_event_interruptible(rdp->nocb_wq, rdp->nocb_head); + /* Memory barrier provide by xchg() below. */ } else if (firsttime) { firsttime = 0; trace_rcu_nocb_wake(rdp->rsp->name, rdp->cpu, @@ -2310,6 +2340,22 @@ static int rcu_nocb_kthread(void *arg) return 0; } +/* Is a deferred wakeup of rcu_nocb_kthread() required? */ +static bool rcu_nocb_need_deferred_wakeup(struct rcu_data *rdp) +{ + return ACCESS_ONCE(rdp->nocb_defer_wakeup); +} + +/* Do a deferred wakeup of rcu_nocb_kthread(). */ +static void do_nocb_deferred_wakeup(struct rcu_data *rdp) +{ + if (!rcu_nocb_need_deferred_wakeup(rdp)) + return; + ACCESS_ONCE(rdp->nocb_defer_wakeup) = false; + wake_up(&rdp->nocb_wq); + trace_rcu_nocb_wake(rdp->rsp->name, rdp->cpu, TPS("DeferredWakeEmpty")); +} + /* Initialize per-rcu_data variables for no-CBs CPUs. */ static void __init rcu_boot_init_nocb_percpu_data(struct rcu_data *rdp) { @@ -2365,13 +2411,14 @@ static void rcu_init_one_nocb(struct rcu_node *rnp) } static bool __call_rcu_nocb(struct rcu_data *rdp, struct rcu_head *rhp, - bool lazy) + bool lazy, unsigned long flags) { return 0; } static bool __maybe_unused rcu_nocb_adopt_orphan_cbs(struct rcu_state *rsp, - struct rcu_data *rdp) + struct rcu_data *rdp, + unsigned long flags) { return 0; } @@ -2380,6 +2427,15 @@ static void __init rcu_boot_init_nocb_percpu_data(struct rcu_data *rdp) { } +static bool rcu_nocb_need_deferred_wakeup(struct rcu_data *rdp) +{ + return false; +} + +static void do_nocb_deferred_wakeup(struct rcu_data *rdp) +{ +} + static void __init rcu_spawn_nocb_kthreads(struct rcu_state *rsp) { } @@ -2829,3 +2885,23 @@ static void rcu_sysidle_init_percpu_data(struct rcu_dynticks *rdtp) } #endif /* #else #ifdef CONFIG_NO_HZ_FULL_SYSIDLE */ + +/* + * Is this CPU a NO_HZ_FULL CPU that should ignore RCU so that the + * grace-period kthread will do force_quiescent_state() processing? + * The idea is to avoid waking up RCU core processing on such a + * CPU unless the grace period has extended for too long. + * + * This code relies on the fact that all NO_HZ_FULL CPUs are also + * CONFIG_RCU_NOCB_CPUs. + */ +static bool rcu_nohz_full_cpu(struct rcu_state *rsp) +{ +#ifdef CONFIG_NO_HZ_FULL + if (tick_nohz_full_cpu(smp_processor_id()) && + (!rcu_gp_in_progress(rsp) || + ULONG_CMP_LT(jiffies, ACCESS_ONCE(rsp->gp_start) + HZ))) + return 1; +#endif /* #ifdef CONFIG_NO_HZ_FULL */ + return 0; +} diff --git a/kernel/rcu/tree_trace.c b/kernel/rcu/tree_trace.c index 3596797b7e46..4def475336d4 100644 --- a/kernel/rcu/tree_trace.c +++ b/kernel/rcu/tree_trace.c @@ -364,9 +364,10 @@ static void print_one_rcu_pending(struct seq_file *m, struct rcu_data *rdp) rdp->n_rp_report_qs, rdp->n_rp_cb_ready, rdp->n_rp_cpu_needs_gp); - seq_printf(m, "gpc=%ld gps=%ld nn=%ld\n", + seq_printf(m, "gpc=%ld gps=%ld nn=%ld ndw%ld\n", rdp->n_rp_gp_completed, rdp->n_rp_gp_started, + rdp->n_rp_nocb_defer_wakeup, rdp->n_rp_need_nothing); } diff --git a/kernel/rcu/update.c b/kernel/rcu/update.c index 6cb3dff89e2b..802365ccd591 100644 --- a/kernel/rcu/update.c +++ b/kernel/rcu/update.c @@ -128,6 +128,11 @@ struct lockdep_map rcu_sched_lock_map = STATIC_LOCKDEP_MAP_INIT("rcu_read_lock_sched", &rcu_sched_lock_key); EXPORT_SYMBOL_GPL(rcu_sched_lock_map); +static struct lock_class_key rcu_callback_key; +struct lockdep_map rcu_callback_map = + STATIC_LOCKDEP_MAP_INIT("rcu_callback", &rcu_callback_key); +EXPORT_SYMBOL_GPL(rcu_callback_map); + int notrace debug_lockdep_rcu_enabled(void) { return rcu_scheduler_active && debug_locks && diff --git a/kernel/sched/Makefile b/kernel/sched/Makefile index 7b621409cf15..9a95c8c2af2a 100644 --- a/kernel/sched/Makefile +++ b/kernel/sched/Makefile @@ -11,9 +11,10 @@ ifneq ($(CONFIG_SCHED_OMIT_FRAME_POINTER),y) CFLAGS_core.o := $(PROFILING) -fno-omit-frame-pointer endif -obj-y += core.o proc.o clock.o cputime.o idle_task.o fair.o rt.o stop_task.o +obj-y += core.o proc.o clock.o cputime.o +obj-y += idle_task.o fair.o rt.o deadline.o stop_task.o obj-y += wait.o completion.o -obj-$(CONFIG_SMP) += cpupri.o +obj-$(CONFIG_SMP) += cpupri.o cpudeadline.o obj-$(CONFIG_SCHED_AUTOGROUP) += auto_group.o obj-$(CONFIG_SCHEDSTATS) += stats.o obj-$(CONFIG_SCHED_DEBUG) += debug.o diff --git a/kernel/sched/clock.c b/kernel/sched/clock.c index c3ae1446461c..6bd6a6731b21 100644 --- a/kernel/sched/clock.c +++ b/kernel/sched/clock.c @@ -26,9 +26,10 @@ * at 0 on boot (but people really shouldn't rely on that). * * cpu_clock(i) -- can be used from any context, including NMI. - * sched_clock_cpu(i) -- must be used with local IRQs disabled (implied by NMI) * local_clock() -- is cpu_clock() on the current cpu. * + * sched_clock_cpu(i) + * * How: * * The implementation either uses sched_clock() when @@ -50,15 +51,6 @@ * Furthermore, explicit sleep and wakeup hooks allow us to account for time * that is otherwise invisible (TSC gets stopped). * - * - * Notes: - * - * The !IRQ-safetly of sched_clock() and sched_clock_cpu() comes from things - * like cpufreq interrupts that can change the base clock (TSC) multiplier - * and cause funny jumps in time -- although the filtering provided by - * sched_clock_cpu() should mitigate serious artifacts we cannot rely on it - * in general since for !CONFIG_HAVE_UNSTABLE_SCHED_CLOCK we fully rely on - * sched_clock(). */ #include <linux/spinlock.h> #include <linux/hardirq.h> @@ -66,6 +58,8 @@ #include <linux/percpu.h> #include <linux/ktime.h> #include <linux/sched.h> +#include <linux/static_key.h> +#include <linux/workqueue.h> /* * Scheduler clock - returns current time in nanosec units. @@ -82,7 +76,37 @@ EXPORT_SYMBOL_GPL(sched_clock); __read_mostly int sched_clock_running; #ifdef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK -__read_mostly int sched_clock_stable; +static struct static_key __sched_clock_stable = STATIC_KEY_INIT; + +int sched_clock_stable(void) +{ + if (static_key_false(&__sched_clock_stable)) + return false; + return true; +} + +void set_sched_clock_stable(void) +{ + if (!sched_clock_stable()) + static_key_slow_dec(&__sched_clock_stable); +} + +static void __clear_sched_clock_stable(struct work_struct *work) +{ + /* XXX worry about clock continuity */ + if (sched_clock_stable()) + static_key_slow_inc(&__sched_clock_stable); +} + +static DECLARE_WORK(sched_clock_work, __clear_sched_clock_stable); + +void clear_sched_clock_stable(void) +{ + if (keventd_up()) + schedule_work(&sched_clock_work); + else + __clear_sched_clock_stable(&sched_clock_work); +} struct sched_clock_data { u64 tick_raw; @@ -242,20 +266,20 @@ u64 sched_clock_cpu(int cpu) struct sched_clock_data *scd; u64 clock; - WARN_ON_ONCE(!irqs_disabled()); - - if (sched_clock_stable) + if (sched_clock_stable()) return sched_clock(); if (unlikely(!sched_clock_running)) return 0ull; + preempt_disable(); scd = cpu_sdc(cpu); if (cpu != smp_processor_id()) clock = sched_clock_remote(scd); else clock = sched_clock_local(scd); + preempt_enable(); return clock; } @@ -265,7 +289,7 @@ void sched_clock_tick(void) struct sched_clock_data *scd; u64 now, now_gtod; - if (sched_clock_stable) + if (sched_clock_stable()) return; if (unlikely(!sched_clock_running)) @@ -316,14 +340,10 @@ EXPORT_SYMBOL_GPL(sched_clock_idle_wakeup_event); */ u64 cpu_clock(int cpu) { - u64 clock; - unsigned long flags; - - local_irq_save(flags); - clock = sched_clock_cpu(cpu); - local_irq_restore(flags); + if (static_key_false(&__sched_clock_stable)) + return sched_clock_cpu(cpu); - return clock; + return sched_clock(); } /* @@ -335,14 +355,10 @@ u64 cpu_clock(int cpu) */ u64 local_clock(void) { - u64 clock; - unsigned long flags; + if (static_key_false(&__sched_clock_stable)) + return sched_clock_cpu(raw_smp_processor_id()); - local_irq_save(flags); - clock = sched_clock_cpu(smp_processor_id()); - local_irq_restore(flags); - - return clock; + return sched_clock(); } #else /* CONFIG_HAVE_UNSTABLE_SCHED_CLOCK */ @@ -362,12 +378,12 @@ u64 sched_clock_cpu(int cpu) u64 cpu_clock(int cpu) { - return sched_clock_cpu(cpu); + return sched_clock(); } u64 local_clock(void) { - return sched_clock_cpu(0); + return sched_clock(); } #endif /* CONFIG_HAVE_UNSTABLE_SCHED_CLOCK */ diff --git a/kernel/sched/core.c b/kernel/sched/core.c index a88f4a485c5e..7fea865a810d 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -296,8 +296,6 @@ __read_mostly int scheduler_running; */ int sysctl_sched_rt_runtime = 950000; - - /* * __task_rq_lock - lock the rq @p resides on. */ @@ -899,7 +897,9 @@ static inline int normal_prio(struct task_struct *p) { int prio; - if (task_has_rt_policy(p)) + if (task_has_dl_policy(p)) + prio = MAX_DL_PRIO-1; + else if (task_has_rt_policy(p)) prio = MAX_RT_PRIO-1 - p->rt_priority; else prio = __normal_prio(p); @@ -945,7 +945,7 @@ static inline void check_class_changed(struct rq *rq, struct task_struct *p, if (prev_class->switched_from) prev_class->switched_from(rq, p); p->sched_class->switched_to(rq, p); - } else if (oldprio != p->prio) + } else if (oldprio != p->prio || dl_task(p)) p->sched_class->prio_changed(rq, p, oldprio); } @@ -1108,6 +1108,7 @@ int migrate_swap(struct task_struct *cur, struct task_struct *p) if (!cpumask_test_cpu(arg.src_cpu, tsk_cpus_allowed(arg.dst_task))) goto out; + trace_sched_swap_numa(cur, arg.src_cpu, p, arg.dst_cpu); ret = stop_two_cpus(arg.dst_cpu, arg.src_cpu, migrate_swap_stop, &arg); out: @@ -1499,8 +1500,7 @@ void scheduler_ipi(void) * TIF_NEED_RESCHED remotely (for the first time) will also send * this IPI. */ - if (tif_need_resched()) - set_preempt_need_resched(); + preempt_fold_need_resched(); if (llist_empty(&this_rq()->wake_list) && !tick_nohz_full_cpu(smp_processor_id()) @@ -1717,6 +1717,13 @@ static void __sched_fork(unsigned long clone_flags, struct task_struct *p) memset(&p->se.statistics, 0, sizeof(p->se.statistics)); #endif + RB_CLEAR_NODE(&p->dl.rb_node); + hrtimer_init(&p->dl.dl_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); + p->dl.dl_runtime = p->dl.runtime = 0; + p->dl.dl_deadline = p->dl.deadline = 0; + p->dl.dl_period = 0; + p->dl.flags = 0; + INIT_LIST_HEAD(&p->rt.run_list); #ifdef CONFIG_PREEMPT_NOTIFIERS @@ -1763,12 +1770,34 @@ void set_numabalancing_state(bool enabled) numabalancing_enabled = enabled; } #endif /* CONFIG_SCHED_DEBUG */ -#endif /* CONFIG_NUMA_BALANCING */ + +#ifdef CONFIG_PROC_SYSCTL +int sysctl_numa_balancing(struct ctl_table *table, int write, + void __user *buffer, size_t *lenp, loff_t *ppos) +{ + struct ctl_table t; + int err; + int state = numabalancing_enabled; + + if (write && !capable(CAP_SYS_ADMIN)) + return -EPERM; + + t = *table; + t.data = &state; + err = proc_dointvec_minmax(&t, write, buffer, lenp, ppos); + if (err < 0) + return err; + if (write) + set_numabalancing_state(state); + return err; +} +#endif +#endif /* * fork()/clone()-time setup: */ -void sched_fork(unsigned long clone_flags, struct task_struct *p) +int sched_fork(unsigned long clone_flags, struct task_struct *p) { unsigned long flags; int cpu = get_cpu(); @@ -1790,7 +1819,7 @@ void sched_fork(unsigned long clone_flags, struct task_struct *p) * Revert to default priority/policy on fork if requested. */ if (unlikely(p->sched_reset_on_fork)) { - if (task_has_rt_policy(p)) { + if (task_has_dl_policy(p) || task_has_rt_policy(p)) { p->policy = SCHED_NORMAL; p->static_prio = NICE_TO_PRIO(0); p->rt_priority = 0; @@ -1807,8 +1836,14 @@ void sched_fork(unsigned long clone_flags, struct task_struct *p) p->sched_reset_on_fork = 0; } - if (!rt_prio(p->prio)) + if (dl_prio(p->prio)) { + put_cpu(); + return -EAGAIN; + } else if (rt_prio(p->prio)) { + p->sched_class = &rt_sched_class; + } else { p->sched_class = &fair_sched_class; + } if (p->sched_class->task_fork) p->sched_class->task_fork(p); @@ -1834,12 +1869,125 @@ void sched_fork(unsigned long clone_flags, struct task_struct *p) init_task_preempt_count(p); #ifdef CONFIG_SMP plist_node_init(&p->pushable_tasks, MAX_PRIO); + RB_CLEAR_NODE(&p->pushable_dl_tasks); #endif put_cpu(); + return 0; +} + +unsigned long to_ratio(u64 period, u64 runtime) +{ + if (runtime == RUNTIME_INF) + return 1ULL << 20; + + /* + * Doing this here saves a lot of checks in all + * the calling paths, and returning zero seems + * safe for them anyway. + */ + if (period == 0) + return 0; + + return div64_u64(runtime << 20, period); +} + +#ifdef CONFIG_SMP +inline struct dl_bw *dl_bw_of(int i) +{ + return &cpu_rq(i)->rd->dl_bw; +} + +static inline int dl_bw_cpus(int i) +{ + struct root_domain *rd = cpu_rq(i)->rd; + int cpus = 0; + + for_each_cpu_and(i, rd->span, cpu_active_mask) + cpus++; + + return cpus; +} +#else +inline struct dl_bw *dl_bw_of(int i) +{ + return &cpu_rq(i)->dl.dl_bw; +} + +static inline int dl_bw_cpus(int i) +{ + return 1; +} +#endif + +static inline +void __dl_clear(struct dl_bw *dl_b, u64 tsk_bw) +{ + dl_b->total_bw -= tsk_bw; +} + +static inline +void __dl_add(struct dl_bw *dl_b, u64 tsk_bw) +{ + dl_b->total_bw += tsk_bw; +} + +static inline +bool __dl_overflow(struct dl_bw *dl_b, int cpus, u64 old_bw, u64 new_bw) +{ + return dl_b->bw != -1 && + dl_b->bw * cpus < dl_b->total_bw - old_bw + new_bw; } /* + * We must be sure that accepting a new task (or allowing changing the + * parameters of an existing one) is consistent with the bandwidth + * constraints. If yes, this function also accordingly updates the currently + * allocated bandwidth to reflect the new situation. + * + * This function is called while holding p's rq->lock. + */ +static int dl_overflow(struct task_struct *p, int policy, + const struct sched_attr *attr) +{ + + struct dl_bw *dl_b = dl_bw_of(task_cpu(p)); + u64 period = attr->sched_period; + u64 runtime = attr->sched_runtime; + u64 new_bw = dl_policy(policy) ? to_ratio(period, runtime) : 0; + int cpus, err = -1; + + if (new_bw == p->dl.dl_bw) + return 0; + + /* + * Either if a task, enters, leave, or stays -deadline but changes + * its parameters, we may need to update accordingly the total + * allocated bandwidth of the container. + */ + raw_spin_lock(&dl_b->lock); + cpus = dl_bw_cpus(task_cpu(p)); + if (dl_policy(policy) && !task_has_dl_policy(p) && + !__dl_overflow(dl_b, cpus, 0, new_bw)) { + __dl_add(dl_b, new_bw); + err = 0; + } else if (dl_policy(policy) && task_has_dl_policy(p) && + !__dl_overflow(dl_b, cpus, p->dl.dl_bw, new_bw)) { + __dl_clear(dl_b, p->dl.dl_bw); + __dl_add(dl_b, new_bw); + err = 0; + } else if (!dl_policy(policy) && task_has_dl_policy(p)) { + __dl_clear(dl_b, p->dl.dl_bw); + err = 0; + } + raw_spin_unlock(&dl_b->lock); + + return err; +} + +extern void init_dl_bw(struct dl_bw *dl_b); + +/* * wake_up_new_task - wake up a newly created task for the first time. * * This function will do some initial scheduler statistics housekeeping @@ -2003,6 +2151,9 @@ static void finish_task_switch(struct rq *rq, struct task_struct *prev) if (unlikely(prev_state == TASK_DEAD)) { task_numa_free(prev); + if (prev->sched_class->task_dead) + prev->sched_class->task_dead(prev); + /* * Remove function-return probe instances associated with this * task and put them back on the free list. @@ -2296,7 +2447,7 @@ void scheduler_tick(void) #ifdef CONFIG_SMP rq->idle_balance = idle_cpu(cpu); - trigger_load_balance(rq, cpu); + trigger_load_balance(rq); #endif rq_last_tick_reset(rq); } @@ -2414,10 +2565,10 @@ static inline void schedule_debug(struct task_struct *prev) { /* * Test if we are atomic. Since do_exit() needs to call into - * schedule() atomically, we ignore that path for now. - * Otherwise, whine if we are scheduling when we should not be. + * schedule() atomically, we ignore that path. Otherwise whine + * if we are scheduling when we should not. */ - if (unlikely(in_atomic_preempt_off() && !prev->exit_state)) + if (unlikely(in_atomic_preempt_off() && prev->state != TASK_DEAD)) __schedule_bug(prev); rcu_sleep_check(); @@ -2761,11 +2912,11 @@ EXPORT_SYMBOL(sleep_on_timeout); */ void rt_mutex_setprio(struct task_struct *p, int prio) { - int oldprio, on_rq, running; + int oldprio, on_rq, running, enqueue_flag = 0; struct rq *rq; const struct sched_class *prev_class; - BUG_ON(prio < 0 || prio > MAX_PRIO); + BUG_ON(prio > MAX_PRIO); rq = __task_rq_lock(p); @@ -2788,6 +2939,7 @@ void rt_mutex_setprio(struct task_struct *p, int prio) } trace_sched_pi_setprio(p, prio); + p->pi_top_task = rt_mutex_get_top_task(p); oldprio = p->prio; prev_class = p->sched_class; on_rq = p->on_rq; @@ -2797,23 +2949,49 @@ void rt_mutex_setprio(struct task_struct *p, int prio) if (running) p->sched_class->put_prev_task(rq, p); - if (rt_prio(prio)) + /* + * Boosting condition are: + * 1. -rt task is running and holds mutex A + * --> -dl task blocks on mutex A + * + * 2. -dl task is running and holds mutex A + * --> -dl task blocks on mutex A and could preempt the + * running task + */ + if (dl_prio(prio)) { + if (!dl_prio(p->normal_prio) || (p->pi_top_task && + dl_entity_preempt(&p->pi_top_task->dl, &p->dl))) { + p->dl.dl_boosted = 1; + p->dl.dl_throttled = 0; + enqueue_flag = ENQUEUE_REPLENISH; + } else + p->dl.dl_boosted = 0; + p->sched_class = &dl_sched_class; + } else if (rt_prio(prio)) { + if (dl_prio(oldprio)) + p->dl.dl_boosted = 0; + if (oldprio < prio) + enqueue_flag = ENQUEUE_HEAD; p->sched_class = &rt_sched_class; - else + } else { + if (dl_prio(oldprio)) + p->dl.dl_boosted = 0; p->sched_class = &fair_sched_class; + } p->prio = prio; if (running) p->sched_class->set_curr_task(rq); if (on_rq) - enqueue_task(rq, p, oldprio < prio ? ENQUEUE_HEAD : 0); + enqueue_task(rq, p, enqueue_flag); check_class_changed(rq, p, prev_class, oldprio); out_unlock: __task_rq_unlock(rq); } #endif + void set_user_nice(struct task_struct *p, long nice) { int old_prio, delta, on_rq; @@ -2831,9 +3009,9 @@ void set_user_nice(struct task_struct *p, long nice) * The RT priorities are set via sched_setscheduler(), but we still * allow the 'normal' nice value to be set - but as expected * it wont have any effect on scheduling until the task is - * SCHED_FIFO/SCHED_RR: + * SCHED_DEADLINE, SCHED_FIFO or SCHED_RR: */ - if (task_has_rt_policy(p)) { + if (task_has_dl_policy(p) || task_has_rt_policy(p)) { p->static_prio = NICE_TO_PRIO(nice); goto out_unlock; } @@ -2988,22 +3166,95 @@ static struct task_struct *find_process_by_pid(pid_t pid) return pid ? find_task_by_vpid(pid) : current; } -/* Actually do priority change: must hold rq lock. */ +/* + * This function initializes the sched_dl_entity of a newly becoming + * SCHED_DEADLINE task. + * + * Only the static values are considered here, the actual runtime and the + * absolute deadline will be properly calculated when the task is enqueued + * for the first time with its new policy. + */ static void -__setscheduler(struct rq *rq, struct task_struct *p, int policy, int prio) +__setparam_dl(struct task_struct *p, const struct sched_attr *attr) +{ + struct sched_dl_entity *dl_se = &p->dl; + + init_dl_task_timer(dl_se); + dl_se->dl_runtime = attr->sched_runtime; + dl_se->dl_deadline = attr->sched_deadline; + dl_se->dl_period = attr->sched_period ?: dl_se->dl_deadline; + dl_se->flags = attr->sched_flags; + dl_se->dl_bw = to_ratio(dl_se->dl_period, dl_se->dl_runtime); + dl_se->dl_throttled = 0; + dl_se->dl_new = 1; +} + +/* Actually do priority change: must hold pi & rq lock. */ +static void __setscheduler(struct rq *rq, struct task_struct *p, + const struct sched_attr *attr) { + int policy = attr->sched_policy; + + if (policy == -1) /* setparam */ + policy = p->policy; + p->policy = policy; - p->rt_priority = prio; + + if (dl_policy(policy)) + __setparam_dl(p, attr); + else if (fair_policy(policy)) + p->static_prio = NICE_TO_PRIO(attr->sched_nice); + + /* + * __sched_setscheduler() ensures attr->sched_priority == 0 when + * !rt_policy. Always setting this ensures that things like + * getparam()/getattr() don't report silly values for !rt tasks. + */ + p->rt_priority = attr->sched_priority; + p->normal_prio = normal_prio(p); - /* we are holding p->pi_lock already */ p->prio = rt_mutex_getprio(p); - if (rt_prio(p->prio)) + + if (dl_prio(p->prio)) + p->sched_class = &dl_sched_class; + else if (rt_prio(p->prio)) p->sched_class = &rt_sched_class; else p->sched_class = &fair_sched_class; + set_load_weight(p); } +static void +__getparam_dl(struct task_struct *p, struct sched_attr *attr) +{ + struct sched_dl_entity *dl_se = &p->dl; + + attr->sched_priority = p->rt_priority; + attr->sched_runtime = dl_se->dl_runtime; + attr->sched_deadline = dl_se->dl_deadline; + attr->sched_period = dl_se->dl_period; + attr->sched_flags = dl_se->flags; +} + +/* + * This function validates the new parameters of a -deadline task. + * We ask for the deadline not being zero, and greater or equal + * than the runtime, as well as the period of being zero or + * greater than deadline. Furthermore, we have to be sure that + * user parameters are above the internal resolution (1us); we + * check sched_runtime only since it is always the smaller one. + */ +static bool +__checkparam_dl(const struct sched_attr *attr) +{ + return attr && attr->sched_deadline != 0 && + (attr->sched_period == 0 || + (s64)(attr->sched_period - attr->sched_deadline) >= 0) && + (s64)(attr->sched_deadline - attr->sched_runtime ) >= 0 && + attr->sched_runtime >= (2 << (DL_SCALE - 1)); +} + /* * check the target process has a UID that matches the current process's */ @@ -3020,10 +3271,12 @@ static bool check_same_owner(struct task_struct *p) return match; } -static int __sched_setscheduler(struct task_struct *p, int policy, - const struct sched_param *param, bool user) +static int __sched_setscheduler(struct task_struct *p, + const struct sched_attr *attr, + bool user) { int retval, oldprio, oldpolicy = -1, on_rq, running; + int policy = attr->sched_policy; unsigned long flags; const struct sched_class *prev_class; struct rq *rq; @@ -3037,31 +3290,40 @@ recheck: reset_on_fork = p->sched_reset_on_fork; policy = oldpolicy = p->policy; } else { - reset_on_fork = !!(policy & SCHED_RESET_ON_FORK); - policy &= ~SCHED_RESET_ON_FORK; + reset_on_fork = !!(attr->sched_flags & SCHED_FLAG_RESET_ON_FORK); - if (policy != SCHED_FIFO && policy != SCHED_RR && + if (policy != SCHED_DEADLINE && + policy != SCHED_FIFO && policy != SCHED_RR && policy != SCHED_NORMAL && policy != SCHED_BATCH && policy != SCHED_IDLE) return -EINVAL; } + if (attr->sched_flags & ~(SCHED_FLAG_RESET_ON_FORK)) + return -EINVAL; + /* * Valid priorities for SCHED_FIFO and SCHED_RR are * 1..MAX_USER_RT_PRIO-1, valid priority for SCHED_NORMAL, * SCHED_BATCH and SCHED_IDLE is 0. */ - if (param->sched_priority < 0 || - (p->mm && param->sched_priority > MAX_USER_RT_PRIO-1) || - (!p->mm && param->sched_priority > MAX_RT_PRIO-1)) + if ((p->mm && attr->sched_priority > MAX_USER_RT_PRIO-1) || + (!p->mm && attr->sched_priority > MAX_RT_PRIO-1)) return -EINVAL; - if (rt_policy(policy) != (param->sched_priority != 0)) + if ((dl_policy(policy) && !__checkparam_dl(attr)) || + (rt_policy(policy) != (attr->sched_priority != 0))) return -EINVAL; /* * Allow unprivileged RT tasks to decrease priority: */ if (user && !capable(CAP_SYS_NICE)) { + if (fair_policy(policy)) { + if (attr->sched_nice < TASK_NICE(p) && + !can_nice(p, attr->sched_nice)) + return -EPERM; + } + if (rt_policy(policy)) { unsigned long rlim_rtprio = task_rlimit(p, RLIMIT_RTPRIO); @@ -3071,8 +3333,8 @@ recheck: return -EPERM; /* can't increase priority */ - if (param->sched_priority > p->rt_priority && - param->sched_priority > rlim_rtprio) + if (attr->sched_priority > p->rt_priority && + attr->sched_priority > rlim_rtprio) return -EPERM; } @@ -3120,14 +3382,21 @@ recheck: /* * If not changing anything there's no need to proceed further: */ - if (unlikely(policy == p->policy && (!rt_policy(policy) || - param->sched_priority == p->rt_priority))) { + if (unlikely(policy == p->policy)) { + if (fair_policy(policy) && attr->sched_nice != TASK_NICE(p)) + goto change; + if (rt_policy(policy) && attr->sched_priority != p->rt_priority) + goto change; + if (dl_policy(policy)) + goto change; + task_rq_unlock(rq, p, &flags); return 0; } +change: -#ifdef CONFIG_RT_GROUP_SCHED if (user) { +#ifdef CONFIG_RT_GROUP_SCHED /* * Do not allow realtime tasks into groups that have no runtime * assigned. @@ -3138,8 +3407,24 @@ recheck: task_rq_unlock(rq, p, &flags); return -EPERM; } - } #endif +#ifdef CONFIG_SMP + if (dl_bandwidth_enabled() && dl_policy(policy)) { + cpumask_t *span = rq->rd->span; + + /* + * Don't allow tasks with an affinity mask smaller than + * the entire root_domain to become SCHED_DEADLINE. We + * will also fail if there's no bandwidth available. + */ + if (!cpumask_subset(span, &p->cpus_allowed) || + rq->rd->dl_bw.bw == 0) { + task_rq_unlock(rq, p, &flags); + return -EPERM; + } + } +#endif + } /* recheck policy now with rq lock held */ if (unlikely(oldpolicy != -1 && oldpolicy != p->policy)) { @@ -3147,6 +3432,17 @@ recheck: task_rq_unlock(rq, p, &flags); goto recheck; } + + /* + * If setscheduling to SCHED_DEADLINE (or changing the parameters + * of a SCHED_DEADLINE task) we need to check if enough bandwidth + * is available. + */ + if ((dl_policy(policy) || dl_task(p)) && dl_overflow(p, policy, attr)) { + task_rq_unlock(rq, p, &flags); + return -EBUSY; + } + on_rq = p->on_rq; running = task_current(rq, p); if (on_rq) @@ -3158,7 +3454,7 @@ recheck: oldprio = p->prio; prev_class = p->sched_class; - __setscheduler(rq, p, policy, param->sched_priority); + __setscheduler(rq, p, attr); if (running) p->sched_class->set_curr_task(rq); @@ -3173,6 +3469,26 @@ recheck: return 0; } +static int _sched_setscheduler(struct task_struct *p, int policy, + const struct sched_param *param, bool check) +{ + struct sched_attr attr = { + .sched_policy = policy, + .sched_priority = param->sched_priority, + .sched_nice = PRIO_TO_NICE(p->static_prio), + }; + + /* + * Fixup the legacy SCHED_RESET_ON_FORK hack + */ + if (policy & SCHED_RESET_ON_FORK) { + attr.sched_flags |= SCHED_FLAG_RESET_ON_FORK; + policy &= ~SCHED_RESET_ON_FORK; + attr.sched_policy = policy; + } + + return __sched_setscheduler(p, &attr, check); +} /** * sched_setscheduler - change the scheduling policy and/or RT priority of a thread. * @p: the task in question. @@ -3186,10 +3502,16 @@ recheck: int sched_setscheduler(struct task_struct *p, int policy, const struct sched_param *param) { - return __sched_setscheduler(p, policy, param, true); + return _sched_setscheduler(p, policy, param, true); } EXPORT_SYMBOL_GPL(sched_setscheduler); +int sched_setattr(struct task_struct *p, const struct sched_attr *attr) +{ + return __sched_setscheduler(p, attr, true); +} +EXPORT_SYMBOL_GPL(sched_setattr); + /** * sched_setscheduler_nocheck - change the scheduling policy and/or RT priority of a thread from kernelspace. * @p: the task in question. @@ -3206,7 +3528,7 @@ EXPORT_SYMBOL_GPL(sched_setscheduler); int sched_setscheduler_nocheck(struct task_struct *p, int policy, const struct sched_param *param) { - return __sched_setscheduler(p, policy, param, false); + return _sched_setscheduler(p, policy, param, false); } static int @@ -3231,6 +3553,79 @@ do_sched_setscheduler(pid_t pid, int policy, struct sched_param __user *param) return retval; } +/* + * Mimics kernel/events/core.c perf_copy_attr(). + */ +static int sched_copy_attr(struct sched_attr __user *uattr, + struct sched_attr *attr) +{ + u32 size; + int ret; + + if (!access_ok(VERIFY_WRITE, uattr, SCHED_ATTR_SIZE_VER0)) + return -EFAULT; + + /* + * zero the full structure, so that a short copy will be nice. + */ + memset(attr, 0, sizeof(*attr)); + + ret = get_user(size, &uattr->size); + if (ret) + return ret; + + if (size > PAGE_SIZE) /* silly large */ + goto err_size; + + if (!size) /* abi compat */ + size = SCHED_ATTR_SIZE_VER0; + + if (size < SCHED_ATTR_SIZE_VER0) + goto err_size; + + /* + * If we're handed a bigger struct than we know of, + * ensure all the unknown bits are 0 - i.e. new + * user-space does not rely on any kernel feature + * extensions we dont know about yet. + */ + if (size > sizeof(*attr)) { + unsigned char __user *addr; + unsigned char __user *end; + unsigned char val; + + addr = (void __user *)uattr + sizeof(*attr); + end = (void __user *)uattr + size; + + for (; addr < end; addr++) { + ret = get_user(val, addr); + if (ret) + return ret; + if (val) + goto err_size; + } + size = sizeof(*attr); + } + + ret = copy_from_user(attr, uattr, size); + if (ret) + return -EFAULT; + + /* + * XXX: do we want to be lenient like existing syscalls; or do we want + * to be strict and return an error on out-of-bounds values? + */ + attr->sched_nice = clamp(attr->sched_nice, -20, 19); + +out: + return ret; + +err_size: + put_user(sizeof(*attr), &uattr->size); + ret = -E2BIG; + goto out; +} + /** * sys_sched_setscheduler - set/change the scheduler policy and RT priority * @pid: the pid in question. @@ -3262,6 +3657,33 @@ SYSCALL_DEFINE2(sched_setparam, pid_t, pid, struct sched_param __user *, param) } /** + * sys_sched_setattr - same as above, but with extended sched_attr + * @pid: the pid in question. + * @uattr: structure containing the extended parameters. + */ +SYSCALL_DEFINE2(sched_setattr, pid_t, pid, struct sched_attr __user *, uattr) +{ + struct sched_attr attr; + struct task_struct *p; + int retval; + + if (!uattr || pid < 0) + return -EINVAL; + + if (sched_copy_attr(uattr, &attr)) + return -EFAULT; + + rcu_read_lock(); + retval = -ESRCH; + p = find_process_by_pid(pid); + if (p != NULL) + retval = sched_setattr(p, &attr); + rcu_read_unlock(); + + return retval; +} + +/** * sys_sched_getscheduler - get the policy (scheduling class) of a thread * @pid: the pid in question. * @@ -3316,6 +3738,10 @@ SYSCALL_DEFINE2(sched_getparam, pid_t, pid, struct sched_param __user *, param) if (retval) goto out_unlock; + if (task_has_dl_policy(p)) { + retval = -EINVAL; + goto out_unlock; + } lp.sched_priority = p->rt_priority; rcu_read_unlock(); @@ -3331,6 +3757,96 @@ out_unlock: return retval; } +static int sched_read_attr(struct sched_attr __user *uattr, + struct sched_attr *attr, + unsigned int usize) +{ + int ret; + + if (!access_ok(VERIFY_WRITE, uattr, usize)) + return -EFAULT; + + /* + * If we're handed a smaller struct than we know of, + * ensure all the unknown bits are 0 - i.e. old + * user-space does not get uncomplete information. + */ + if (usize < sizeof(*attr)) { + unsigned char *addr; + unsigned char *end; + + addr = (void *)attr + usize; + end = (void *)attr + sizeof(*attr); + + for (; addr < end; addr++) { + if (*addr) + goto err_size; + } + + attr->size = usize; + } + + ret = copy_to_user(uattr, attr, usize); + if (ret) + return -EFAULT; + +out: + return ret; + +err_size: + ret = -E2BIG; + goto out; +} + +/** + * sys_sched_getattr - similar to sched_getparam, but with sched_attr + * @pid: the pid in question. + * @uattr: structure containing the extended parameters. + * @size: sizeof(attr) for fwd/bwd comp. + */ +SYSCALL_DEFINE3(sched_getattr, pid_t, pid, struct sched_attr __user *, uattr, + unsigned int, size) +{ + struct sched_attr attr = { + .size = sizeof(struct sched_attr), + }; + struct task_struct *p; + int retval; + + if (!uattr || pid < 0 || size > PAGE_SIZE || + size < SCHED_ATTR_SIZE_VER0) + return -EINVAL; + + rcu_read_lock(); + p = find_process_by_pid(pid); + retval = -ESRCH; + if (!p) + goto out_unlock; + + retval = security_task_getscheduler(p); + if (retval) + goto out_unlock; + + attr.sched_policy = p->policy; + if (p->sched_reset_on_fork) + attr.sched_flags |= SCHED_FLAG_RESET_ON_FORK; + if (task_has_dl_policy(p)) + __getparam_dl(p, &attr); + else if (task_has_rt_policy(p)) + attr.sched_priority = p->rt_priority; + else + attr.sched_nice = TASK_NICE(p); + + rcu_read_unlock(); + + retval = sched_read_attr(uattr, &attr, size); + return retval; + +out_unlock: + rcu_read_unlock(); + return retval; +} + long sched_setaffinity(pid_t pid, const struct cpumask *in_mask) { cpumask_var_t cpus_allowed, new_mask; @@ -3375,8 +3891,26 @@ long sched_setaffinity(pid_t pid, const struct cpumask *in_mask) if (retval) goto out_unlock; + cpuset_cpus_allowed(p, cpus_allowed); cpumask_and(new_mask, in_mask, cpus_allowed); + + /* + * Since bandwidth control happens on root_domain basis, + * if admission test is enabled, we only admit -deadline + * tasks allowed to run on all the CPUs in the task's + * root_domain. + */ +#ifdef CONFIG_SMP + if (task_has_dl_policy(p)) { + const struct cpumask *span = task_rq(p)->rd->span; + + if (dl_bandwidth_enabled() && !cpumask_subset(span, new_mask)) { + retval = -EBUSY; + goto out_unlock; + } + } +#endif again: retval = set_cpus_allowed_ptr(p, new_mask); @@ -3653,7 +4187,7 @@ again: } double_rq_lock(rq, p_rq); - while (task_rq(p) != p_rq) { + if (task_rq(p) != p_rq) { double_rq_unlock(rq, p_rq); goto again; } @@ -3742,6 +4276,7 @@ SYSCALL_DEFINE1(sched_get_priority_max, int, policy) case SCHED_RR: ret = MAX_USER_RT_PRIO-1; break; + case SCHED_DEADLINE: case SCHED_NORMAL: case SCHED_BATCH: case SCHED_IDLE: @@ -3768,6 +4303,7 @@ SYSCALL_DEFINE1(sched_get_priority_min, int, policy) case SCHED_RR: ret = 1; break; + case SCHED_DEADLINE: case SCHED_NORMAL: case SCHED_BATCH: case SCHED_IDLE: @@ -4090,6 +4626,7 @@ int migrate_task_to(struct task_struct *p, int target_cpu) /* TODO: This is not properly updating schedstats */ + trace_sched_move_numa(p, curr_cpu, target_cpu); return stop_one_cpu(curr_cpu, migration_cpu_stop, &arg); } @@ -4514,13 +5051,31 @@ static int sched_cpu_active(struct notifier_block *nfb, static int sched_cpu_inactive(struct notifier_block *nfb, unsigned long action, void *hcpu) { + unsigned long flags; + long cpu = (long)hcpu; + switch (action & ~CPU_TASKS_FROZEN) { case CPU_DOWN_PREPARE: - set_cpu_active((long)hcpu, false); + set_cpu_active(cpu, false); + + /* explicitly allow suspend */ + if (!(action & CPU_TASKS_FROZEN)) { + struct dl_bw *dl_b = dl_bw_of(cpu); + bool overflow; + int cpus; + + raw_spin_lock_irqsave(&dl_b->lock, flags); + cpus = dl_bw_cpus(cpu); + overflow = __dl_overflow(dl_b, cpus, 0, 0); + raw_spin_unlock_irqrestore(&dl_b->lock, flags); + + if (overflow) + return notifier_from_errno(-EBUSY); + } return NOTIFY_OK; - default: - return NOTIFY_DONE; } + + return NOTIFY_DONE; } static int __init migration_init(void) @@ -4739,6 +5294,8 @@ static void free_rootdomain(struct rcu_head *rcu) struct root_domain *rd = container_of(rcu, struct root_domain, rcu); cpupri_cleanup(&rd->cpupri); + cpudl_cleanup(&rd->cpudl); + free_cpumask_var(rd->dlo_mask); free_cpumask_var(rd->rto_mask); free_cpumask_var(rd->online); free_cpumask_var(rd->span); @@ -4790,8 +5347,14 @@ static int init_rootdomain(struct root_domain *rd) goto out; if (!alloc_cpumask_var(&rd->online, GFP_KERNEL)) goto free_span; - if (!alloc_cpumask_var(&rd->rto_mask, GFP_KERNEL)) + if (!alloc_cpumask_var(&rd->dlo_mask, GFP_KERNEL)) goto free_online; + if (!alloc_cpumask_var(&rd->rto_mask, GFP_KERNEL)) + goto free_dlo_mask; + + init_dl_bw(&rd->dl_bw); + if (cpudl_init(&rd->cpudl) != 0) + goto free_dlo_mask; if (cpupri_init(&rd->cpupri) != 0) goto free_rto_mask; @@ -4799,6 +5362,8 @@ static int init_rootdomain(struct root_domain *rd) free_rto_mask: free_cpumask_var(rd->rto_mask); +free_dlo_mask: + free_cpumask_var(rd->dlo_mask); free_online: free_cpumask_var(rd->online); free_span: @@ -6150,6 +6715,7 @@ void __init sched_init_smp(void) free_cpumask_var(non_isolated_cpus); init_sched_rt_class(); + init_sched_dl_class(); } #else void __init sched_init_smp(void) @@ -6219,13 +6785,15 @@ void __init sched_init(void) #endif /* CONFIG_CPUMASK_OFFSTACK */ } + init_rt_bandwidth(&def_rt_bandwidth, + global_rt_period(), global_rt_runtime()); + init_dl_bandwidth(&def_dl_bandwidth, + global_rt_period(), global_rt_runtime()); + #ifdef CONFIG_SMP init_defrootdomain(); #endif - init_rt_bandwidth(&def_rt_bandwidth, - global_rt_period(), global_rt_runtime()); - #ifdef CONFIG_RT_GROUP_SCHED init_rt_bandwidth(&root_task_group.rt_bandwidth, global_rt_period(), global_rt_runtime()); @@ -6249,6 +6817,7 @@ void __init sched_init(void) rq->calc_load_update = jiffies + LOAD_FREQ; init_cfs_rq(&rq->cfs); init_rt_rq(&rq->rt, rq); + init_dl_rq(&rq->dl, rq); #ifdef CONFIG_FAIR_GROUP_SCHED root_task_group.shares = ROOT_TASK_GROUP_LOAD; INIT_LIST_HEAD(&rq->leaf_cfs_rq_list); @@ -6320,10 +6889,6 @@ void __init sched_init(void) INIT_HLIST_HEAD(&init_task.preempt_notifiers); #endif -#ifdef CONFIG_RT_MUTEXES - plist_head_init(&init_task.pi_waiters); -#endif - /* * The boot idle thread does lazy MMU switching as well: */ @@ -6397,13 +6962,16 @@ EXPORT_SYMBOL(__might_sleep); static void normalize_task(struct rq *rq, struct task_struct *p) { const struct sched_class *prev_class = p->sched_class; + struct sched_attr attr = { + .sched_policy = SCHED_NORMAL, + }; int old_prio = p->prio; int on_rq; on_rq = p->on_rq; if (on_rq) dequeue_task(rq, p, 0); - __setscheduler(rq, p, SCHED_NORMAL, 0); + __setscheduler(rq, p, &attr); if (on_rq) { enqueue_task(rq, p, 0); resched_task(rq->curr); @@ -6433,7 +7001,7 @@ void normalize_rt_tasks(void) p->se.statistics.block_start = 0; #endif - if (!rt_task(p)) { + if (!dl_task(p) && !rt_task(p)) { /* * Renice negative nice level userspace * tasks back to 0: @@ -6628,16 +7196,6 @@ void sched_move_task(struct task_struct *tsk) } #endif /* CONFIG_CGROUP_SCHED */ -#if defined(CONFIG_RT_GROUP_SCHED) || defined(CONFIG_CFS_BANDWIDTH) -static unsigned long to_ratio(u64 period, u64 runtime) -{ - if (runtime == RUNTIME_INF) - return 1ULL << 20; - - return div64_u64(runtime << 20, period); -} -#endif - #ifdef CONFIG_RT_GROUP_SCHED /* * Ensure that the real time constraints are schedulable. @@ -6811,24 +7369,13 @@ static long sched_group_rt_period(struct task_group *tg) do_div(rt_period_us, NSEC_PER_USEC); return rt_period_us; } +#endif /* CONFIG_RT_GROUP_SCHED */ +#ifdef CONFIG_RT_GROUP_SCHED static int sched_rt_global_constraints(void) { - u64 runtime, period; int ret = 0; - if (sysctl_sched_rt_period <= 0) - return -EINVAL; - - runtime = global_rt_runtime(); - period = global_rt_period(); - - /* - * Sanity check on the sysctl variables. - */ - if (runtime > period && runtime != RUNTIME_INF) - return -EINVAL; - mutex_lock(&rt_constraints_mutex); read_lock(&tasklist_lock); ret = __rt_schedulable(NULL, 0, 0); @@ -6851,17 +7398,7 @@ static int sched_rt_can_attach(struct task_group *tg, struct task_struct *tsk) static int sched_rt_global_constraints(void) { unsigned long flags; - int i; - - if (sysctl_sched_rt_period <= 0) - return -EINVAL; - - /* - * There's always some RT tasks in the root group - * -- migration, kstopmachine etc.. - */ - if (sysctl_sched_rt_runtime == 0) - return -EBUSY; + int i, ret = 0; raw_spin_lock_irqsave(&def_rt_bandwidth.rt_runtime_lock, flags); for_each_possible_cpu(i) { @@ -6873,36 +7410,88 @@ static int sched_rt_global_constraints(void) } raw_spin_unlock_irqrestore(&def_rt_bandwidth.rt_runtime_lock, flags); - return 0; + return ret; } #endif /* CONFIG_RT_GROUP_SCHED */ -int sched_rr_handler(struct ctl_table *table, int write, - void __user *buffer, size_t *lenp, - loff_t *ppos) +static int sched_dl_global_constraints(void) { - int ret; - static DEFINE_MUTEX(mutex); + u64 runtime = global_rt_runtime(); + u64 period = global_rt_period(); + u64 new_bw = to_ratio(period, runtime); + int cpu, ret = 0; - mutex_lock(&mutex); - ret = proc_dointvec(table, write, buffer, lenp, ppos); - /* make sure that internally we keep jiffies */ - /* also, writing zero resets timeslice to default */ - if (!ret && write) { - sched_rr_timeslice = sched_rr_timeslice <= 0 ? - RR_TIMESLICE : msecs_to_jiffies(sched_rr_timeslice); + /* + * Here we want to check the bandwidth not being set to some + * value smaller than the currently allocated bandwidth in + * any of the root_domains. + * + * FIXME: Cycling on all the CPUs is overdoing, but simpler than + * cycling on root_domains... Discussion on different/better + * solutions is welcome! + */ + for_each_possible_cpu(cpu) { + struct dl_bw *dl_b = dl_bw_of(cpu); + + raw_spin_lock(&dl_b->lock); + if (new_bw < dl_b->total_bw) + ret = -EBUSY; + raw_spin_unlock(&dl_b->lock); + + if (ret) + break; } - mutex_unlock(&mutex); + return ret; } +static void sched_dl_do_global(void) +{ + u64 new_bw = -1; + int cpu; + + def_dl_bandwidth.dl_period = global_rt_period(); + def_dl_bandwidth.dl_runtime = global_rt_runtime(); + + if (global_rt_runtime() != RUNTIME_INF) + new_bw = to_ratio(global_rt_period(), global_rt_runtime()); + + /* + * FIXME: As above... + */ + for_each_possible_cpu(cpu) { + struct dl_bw *dl_b = dl_bw_of(cpu); + + raw_spin_lock(&dl_b->lock); + dl_b->bw = new_bw; + raw_spin_unlock(&dl_b->lock); + } +} + +static int sched_rt_global_validate(void) +{ + if (sysctl_sched_rt_period <= 0) + return -EINVAL; + + if (sysctl_sched_rt_runtime > sysctl_sched_rt_period) + return -EINVAL; + + return 0; +} + +static void sched_rt_do_global(void) +{ + def_rt_bandwidth.rt_runtime = global_rt_runtime(); + def_rt_bandwidth.rt_period = ns_to_ktime(global_rt_period()); +} + int sched_rt_handler(struct ctl_table *table, int write, void __user *buffer, size_t *lenp, loff_t *ppos) { - int ret; int old_period, old_runtime; static DEFINE_MUTEX(mutex); + int ret; mutex_lock(&mutex); old_period = sysctl_sched_rt_period; @@ -6911,21 +7500,50 @@ int sched_rt_handler(struct ctl_table *table, int write, ret = proc_dointvec(table, write, buffer, lenp, ppos); if (!ret && write) { + ret = sched_rt_global_validate(); + if (ret) + goto undo; + ret = sched_rt_global_constraints(); - if (ret) { - sysctl_sched_rt_period = old_period; - sysctl_sched_rt_runtime = old_runtime; - } else { - def_rt_bandwidth.rt_runtime = global_rt_runtime(); - def_rt_bandwidth.rt_period = - ns_to_ktime(global_rt_period()); - } + if (ret) + goto undo; + + ret = sched_dl_global_constraints(); + if (ret) + goto undo; + + sched_rt_do_global(); + sched_dl_do_global(); + } + if (0) { +undo: + sysctl_sched_rt_period = old_period; + sysctl_sched_rt_runtime = old_runtime; } mutex_unlock(&mutex); return ret; } +int sched_rr_handler(struct ctl_table *table, int write, + void __user *buffer, size_t *lenp, + loff_t *ppos) +{ + int ret; + static DEFINE_MUTEX(mutex); + + mutex_lock(&mutex); + ret = proc_dointvec(table, write, buffer, lenp, ppos); + /* make sure that internally we keep jiffies */ + /* also, writing zero resets timeslice to default */ + if (!ret && write) { + sched_rr_timeslice = sched_rr_timeslice <= 0 ? + RR_TIMESLICE : msecs_to_jiffies(sched_rr_timeslice); + } + mutex_unlock(&mutex); + return ret; +} + #ifdef CONFIG_CGROUP_SCHED static inline struct task_group *css_tg(struct cgroup_subsys_state *css) @@ -7258,15 +7876,14 @@ static int __cfs_schedulable(struct task_group *tg, u64 period, u64 quota) return ret; } -static int cpu_stats_show(struct cgroup_subsys_state *css, struct cftype *cft, - struct cgroup_map_cb *cb) +static int cpu_stats_show(struct seq_file *sf, void *v) { - struct task_group *tg = css_tg(css); + struct task_group *tg = css_tg(seq_css(sf)); struct cfs_bandwidth *cfs_b = &tg->cfs_bandwidth; - cb->fill(cb, "nr_periods", cfs_b->nr_periods); - cb->fill(cb, "nr_throttled", cfs_b->nr_throttled); - cb->fill(cb, "throttled_time", cfs_b->throttled_time); + seq_printf(sf, "nr_periods %d\n", cfs_b->nr_periods); + seq_printf(sf, "nr_throttled %d\n", cfs_b->nr_throttled); + seq_printf(sf, "throttled_time %llu\n", cfs_b->throttled_time); return 0; } @@ -7320,7 +7937,7 @@ static struct cftype cpu_files[] = { }, { .name = "stat", - .read_map = cpu_stats_show, + .seq_show = cpu_stats_show, }, #endif #ifdef CONFIG_RT_GROUP_SCHED diff --git a/kernel/sched/cpuacct.c b/kernel/sched/cpuacct.c index f64722ff0299..622e0818f905 100644 --- a/kernel/sched/cpuacct.c +++ b/kernel/sched/cpuacct.c @@ -163,10 +163,9 @@ out: return err; } -static int cpuacct_percpu_seq_read(struct cgroup_subsys_state *css, - struct cftype *cft, struct seq_file *m) +static int cpuacct_percpu_seq_show(struct seq_file *m, void *V) { - struct cpuacct *ca = css_ca(css); + struct cpuacct *ca = css_ca(seq_css(m)); u64 percpu; int i; @@ -183,10 +182,9 @@ static const char * const cpuacct_stat_desc[] = { [CPUACCT_STAT_SYSTEM] = "system", }; -static int cpuacct_stats_show(struct cgroup_subsys_state *css, - struct cftype *cft, struct cgroup_map_cb *cb) +static int cpuacct_stats_show(struct seq_file *sf, void *v) { - struct cpuacct *ca = css_ca(css); + struct cpuacct *ca = css_ca(seq_css(sf)); int cpu; s64 val = 0; @@ -196,7 +194,7 @@ static int cpuacct_stats_show(struct cgroup_subsys_state *css, val += kcpustat->cpustat[CPUTIME_NICE]; } val = cputime64_to_clock_t(val); - cb->fill(cb, cpuacct_stat_desc[CPUACCT_STAT_USER], val); + seq_printf(sf, "%s %lld\n", cpuacct_stat_desc[CPUACCT_STAT_USER], val); val = 0; for_each_online_cpu(cpu) { @@ -207,7 +205,7 @@ static int cpuacct_stats_show(struct cgroup_subsys_state *css, } val = cputime64_to_clock_t(val); - cb->fill(cb, cpuacct_stat_desc[CPUACCT_STAT_SYSTEM], val); + seq_printf(sf, "%s %lld\n", cpuacct_stat_desc[CPUACCT_STAT_SYSTEM], val); return 0; } @@ -220,11 +218,11 @@ static struct cftype files[] = { }, { .name = "usage_percpu", - .read_seq_string = cpuacct_percpu_seq_read, + .seq_show = cpuacct_percpu_seq_show, }, { .name = "stat", - .read_map = cpuacct_stats_show, + .seq_show = cpuacct_stats_show, }, { } /* terminate */ }; diff --git a/kernel/sched/cpudeadline.c b/kernel/sched/cpudeadline.c new file mode 100644 index 000000000000..045fc74e3f09 --- /dev/null +++ b/kernel/sched/cpudeadline.c @@ -0,0 +1,216 @@ +/* + * kernel/sched/cpudl.c + * + * Global CPU deadline management + * + * Author: Juri Lelli <j.lelli@sssup.it> + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; version 2 + * of the License. + */ + +#include <linux/gfp.h> +#include <linux/kernel.h> +#include "cpudeadline.h" + +static inline int parent(int i) +{ + return (i - 1) >> 1; +} + +static inline int left_child(int i) +{ + return (i << 1) + 1; +} + +static inline int right_child(int i) +{ + return (i << 1) + 2; +} + +static inline int dl_time_before(u64 a, u64 b) +{ + return (s64)(a - b) < 0; +} + +static void cpudl_exchange(struct cpudl *cp, int a, int b) +{ + int cpu_a = cp->elements[a].cpu, cpu_b = cp->elements[b].cpu; + + swap(cp->elements[a], cp->elements[b]); + swap(cp->cpu_to_idx[cpu_a], cp->cpu_to_idx[cpu_b]); +} + +static void cpudl_heapify(struct cpudl *cp, int idx) +{ + int l, r, largest; + + /* adapted from lib/prio_heap.c */ + while(1) { + l = left_child(idx); + r = right_child(idx); + largest = idx; + + if ((l < cp->size) && dl_time_before(cp->elements[idx].dl, + cp->elements[l].dl)) + largest = l; + if ((r < cp->size) && dl_time_before(cp->elements[largest].dl, + cp->elements[r].dl)) + largest = r; + if (largest == idx) + break; + + /* Push idx down the heap one level and bump one up */ + cpudl_exchange(cp, largest, idx); + idx = largest; + } +} + +static void cpudl_change_key(struct cpudl *cp, int idx, u64 new_dl) +{ + WARN_ON(idx > num_present_cpus() || idx == IDX_INVALID); + + if (dl_time_before(new_dl, cp->elements[idx].dl)) { + cp->elements[idx].dl = new_dl; + cpudl_heapify(cp, idx); + } else { + cp->elements[idx].dl = new_dl; + while (idx > 0 && dl_time_before(cp->elements[parent(idx)].dl, + cp->elements[idx].dl)) { + cpudl_exchange(cp, idx, parent(idx)); + idx = parent(idx); + } + } +} + +static inline int cpudl_maximum(struct cpudl *cp) +{ + return cp->elements[0].cpu; +} + +/* + * cpudl_find - find the best (later-dl) CPU in the system + * @cp: the cpudl max-heap context + * @p: the task + * @later_mask: a mask to fill in with the selected CPUs (or NULL) + * + * Returns: int - best CPU (heap maximum if suitable) + */ +int cpudl_find(struct cpudl *cp, struct task_struct *p, + struct cpumask *later_mask) +{ + int best_cpu = -1; + const struct sched_dl_entity *dl_se = &p->dl; + + if (later_mask && cpumask_and(later_mask, cp->free_cpus, + &p->cpus_allowed) && cpumask_and(later_mask, + later_mask, cpu_active_mask)) { + best_cpu = cpumask_any(later_mask); + goto out; + } else if (cpumask_test_cpu(cpudl_maximum(cp), &p->cpus_allowed) && + dl_time_before(dl_se->deadline, cp->elements[0].dl)) { + best_cpu = cpudl_maximum(cp); + if (later_mask) + cpumask_set_cpu(best_cpu, later_mask); + } + +out: + WARN_ON(best_cpu > num_present_cpus() && best_cpu != -1); + + return best_cpu; +} + +/* + * cpudl_set - update the cpudl max-heap + * @cp: the cpudl max-heap context + * @cpu: the target cpu + * @dl: the new earliest deadline for this cpu + * + * Notes: assumes cpu_rq(cpu)->lock is locked + * + * Returns: (void) + */ +void cpudl_set(struct cpudl *cp, int cpu, u64 dl, int is_valid) +{ + int old_idx, new_cpu; + unsigned long flags; + + WARN_ON(cpu > num_present_cpus()); + + raw_spin_lock_irqsave(&cp->lock, flags); + old_idx = cp->cpu_to_idx[cpu]; + if (!is_valid) { + /* remove item */ + if (old_idx == IDX_INVALID) { + /* + * Nothing to remove if old_idx was invalid. + * This could happen if a rq_offline_dl is + * called for a CPU without -dl tasks running. + */ + goto out; + } + new_cpu = cp->elements[cp->size - 1].cpu; + cp->elements[old_idx].dl = cp->elements[cp->size - 1].dl; + cp->elements[old_idx].cpu = new_cpu; + cp->size--; + cp->cpu_to_idx[new_cpu] = old_idx; + cp->cpu_to_idx[cpu] = IDX_INVALID; + while (old_idx > 0 && dl_time_before( + cp->elements[parent(old_idx)].dl, + cp->elements[old_idx].dl)) { + cpudl_exchange(cp, old_idx, parent(old_idx)); + old_idx = parent(old_idx); + } + cpumask_set_cpu(cpu, cp->free_cpus); + cpudl_heapify(cp, old_idx); + + goto out; + } + + if (old_idx == IDX_INVALID) { + cp->size++; + cp->elements[cp->size - 1].dl = 0; + cp->elements[cp->size - 1].cpu = cpu; + cp->cpu_to_idx[cpu] = cp->size - 1; + cpudl_change_key(cp, cp->size - 1, dl); + cpumask_clear_cpu(cpu, cp->free_cpus); + } else { + cpudl_change_key(cp, old_idx, dl); + } + +out: + raw_spin_unlock_irqrestore(&cp->lock, flags); +} + +/* + * cpudl_init - initialize the cpudl structure + * @cp: the cpudl max-heap context + */ +int cpudl_init(struct cpudl *cp) +{ + int i; + + memset(cp, 0, sizeof(*cp)); + raw_spin_lock_init(&cp->lock); + cp->size = 0; + for (i = 0; i < NR_CPUS; i++) + cp->cpu_to_idx[i] = IDX_INVALID; + if (!alloc_cpumask_var(&cp->free_cpus, GFP_KERNEL)) + return -ENOMEM; + cpumask_setall(cp->free_cpus); + + return 0; +} + +/* + * cpudl_cleanup - clean up the cpudl structure + * @cp: the cpudl max-heap context + */ +void cpudl_cleanup(struct cpudl *cp) +{ + /* + * nothing to do for the moment + */ +} diff --git a/kernel/sched/cpudeadline.h b/kernel/sched/cpudeadline.h new file mode 100644 index 000000000000..a202789a412c --- /dev/null +++ b/kernel/sched/cpudeadline.h @@ -0,0 +1,33 @@ +#ifndef _LINUX_CPUDL_H +#define _LINUX_CPUDL_H + +#include <linux/sched.h> + +#define IDX_INVALID -1 + +struct array_item { + u64 dl; + int cpu; +}; + +struct cpudl { + raw_spinlock_t lock; + int size; + int cpu_to_idx[NR_CPUS]; + struct array_item elements[NR_CPUS]; + cpumask_var_t free_cpus; +}; + + +#ifdef CONFIG_SMP +int cpudl_find(struct cpudl *cp, struct task_struct *p, + struct cpumask *later_mask); +void cpudl_set(struct cpudl *cp, int cpu, u64 dl, int is_valid); +int cpudl_init(struct cpudl *cp); +void cpudl_cleanup(struct cpudl *cp); +#else +#define cpudl_set(cp, cpu, dl) do { } while (0) +#define cpudl_init() do { } while (0) +#endif /* CONFIG_SMP */ + +#endif /* _LINUX_CPUDL_H */ diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c new file mode 100644 index 000000000000..0de248202879 --- /dev/null +++ b/kernel/sched/deadline.c @@ -0,0 +1,1640 @@ +/* + * Deadline Scheduling Class (SCHED_DEADLINE) + * + * Earliest Deadline First (EDF) + Constant Bandwidth Server (CBS). + * + * Tasks that periodically executes their instances for less than their + * runtime won't miss any of their deadlines. + * Tasks that are not periodic or sporadic or that tries to execute more + * than their reserved bandwidth will be slowed down (and may potentially + * miss some of their deadlines), and won't affect any other task. + * + * Copyright (C) 2012 Dario Faggioli <raistlin@linux.it>, + * Juri Lelli <juri.lelli@gmail.com>, + * Michael Trimarchi <michael@amarulasolutions.com>, + * Fabio Checconi <fchecconi@gmail.com> + */ +#include "sched.h" + +#include <linux/slab.h> + +struct dl_bandwidth def_dl_bandwidth; + +static inline struct task_struct *dl_task_of(struct sched_dl_entity *dl_se) +{ + return container_of(dl_se, struct task_struct, dl); +} + +static inline struct rq *rq_of_dl_rq(struct dl_rq *dl_rq) +{ + return container_of(dl_rq, struct rq, dl); +} + +static inline struct dl_rq *dl_rq_of_se(struct sched_dl_entity *dl_se) +{ + struct task_struct *p = dl_task_of(dl_se); + struct rq *rq = task_rq(p); + + return &rq->dl; +} + +static inline int on_dl_rq(struct sched_dl_entity *dl_se) +{ + return !RB_EMPTY_NODE(&dl_se->rb_node); +} + +static inline int is_leftmost(struct task_struct *p, struct dl_rq *dl_rq) +{ + struct sched_dl_entity *dl_se = &p->dl; + + return dl_rq->rb_leftmost == &dl_se->rb_node; +} + +void init_dl_bandwidth(struct dl_bandwidth *dl_b, u64 period, u64 runtime) +{ + raw_spin_lock_init(&dl_b->dl_runtime_lock); + dl_b->dl_period = period; + dl_b->dl_runtime = runtime; +} + +extern unsigned long to_ratio(u64 period, u64 runtime); + +void init_dl_bw(struct dl_bw *dl_b) +{ + raw_spin_lock_init(&dl_b->lock); + raw_spin_lock(&def_dl_bandwidth.dl_runtime_lock); + if (global_rt_runtime() == RUNTIME_INF) + dl_b->bw = -1; + else + dl_b->bw = to_ratio(global_rt_period(), global_rt_runtime()); + raw_spin_unlock(&def_dl_bandwidth.dl_runtime_lock); + dl_b->total_bw = 0; +} + +void init_dl_rq(struct dl_rq *dl_rq, struct rq *rq) +{ + dl_rq->rb_root = RB_ROOT; + +#ifdef CONFIG_SMP + /* zero means no -deadline tasks */ + dl_rq->earliest_dl.curr = dl_rq->earliest_dl.next = 0; + + dl_rq->dl_nr_migratory = 0; + dl_rq->overloaded = 0; + dl_rq->pushable_dl_tasks_root = RB_ROOT; +#else + init_dl_bw(&dl_rq->dl_bw); +#endif +} + +#ifdef CONFIG_SMP + +static inline int dl_overloaded(struct rq *rq) +{ + return atomic_read(&rq->rd->dlo_count); +} + +static inline void dl_set_overload(struct rq *rq) +{ + if (!rq->online) + return; + + cpumask_set_cpu(rq->cpu, rq->rd->dlo_mask); + /* + * Must be visible before the overload count is + * set (as in sched_rt.c). + * + * Matched by the barrier in pull_dl_task(). + */ + smp_wmb(); + atomic_inc(&rq->rd->dlo_count); +} + +static inline void dl_clear_overload(struct rq *rq) +{ + if (!rq->online) + return; + + atomic_dec(&rq->rd->dlo_count); + cpumask_clear_cpu(rq->cpu, rq->rd->dlo_mask); +} + +static void update_dl_migration(struct dl_rq *dl_rq) +{ + if (dl_rq->dl_nr_migratory && dl_rq->dl_nr_total > 1) { + if (!dl_rq->overloaded) { + dl_set_overload(rq_of_dl_rq(dl_rq)); + dl_rq->overloaded = 1; + } + } else if (dl_rq->overloaded) { + dl_clear_overload(rq_of_dl_rq(dl_rq)); + dl_rq->overloaded = 0; + } +} + +static void inc_dl_migration(struct sched_dl_entity *dl_se, struct dl_rq *dl_rq) +{ + struct task_struct *p = dl_task_of(dl_se); + dl_rq = &rq_of_dl_rq(dl_rq)->dl; + + dl_rq->dl_nr_total++; + if (p->nr_cpus_allowed > 1) + dl_rq->dl_nr_migratory++; + + update_dl_migration(dl_rq); +} + +static void dec_dl_migration(struct sched_dl_entity *dl_se, struct dl_rq *dl_rq) +{ + struct task_struct *p = dl_task_of(dl_se); + dl_rq = &rq_of_dl_rq(dl_rq)->dl; + + dl_rq->dl_nr_total--; + if (p->nr_cpus_allowed > 1) + dl_rq->dl_nr_migratory--; + + update_dl_migration(dl_rq); +} + +/* + * The list of pushable -deadline task is not a plist, like in + * sched_rt.c, it is an rb-tree with tasks ordered by deadline. + */ +static void enqueue_pushable_dl_task(struct rq *rq, struct task_struct *p) +{ + struct dl_rq *dl_rq = &rq->dl; + struct rb_node **link = &dl_rq->pushable_dl_tasks_root.rb_node; + struct rb_node *parent = NULL; + struct task_struct *entry; + int leftmost = 1; + + BUG_ON(!RB_EMPTY_NODE(&p->pushable_dl_tasks)); + + while (*link) { + parent = *link; + entry = rb_entry(parent, struct task_struct, + pushable_dl_tasks); + if (dl_entity_preempt(&p->dl, &entry->dl)) + link = &parent->rb_left; + else { + link = &parent->rb_right; + leftmost = 0; + } + } + + if (leftmost) + dl_rq->pushable_dl_tasks_leftmost = &p->pushable_dl_tasks; + + rb_link_node(&p->pushable_dl_tasks, parent, link); + rb_insert_color(&p->pushable_dl_tasks, &dl_rq->pushable_dl_tasks_root); +} + +static void dequeue_pushable_dl_task(struct rq *rq, struct task_struct *p) +{ + struct dl_rq *dl_rq = &rq->dl; + + if (RB_EMPTY_NODE(&p->pushable_dl_tasks)) + return; + + if (dl_rq->pushable_dl_tasks_leftmost == &p->pushable_dl_tasks) { + struct rb_node *next_node; + + next_node = rb_next(&p->pushable_dl_tasks); + dl_rq->pushable_dl_tasks_leftmost = next_node; + } + + rb_erase(&p->pushable_dl_tasks, &dl_rq->pushable_dl_tasks_root); + RB_CLEAR_NODE(&p->pushable_dl_tasks); +} + +static inline int has_pushable_dl_tasks(struct rq *rq) +{ + return !RB_EMPTY_ROOT(&rq->dl.pushable_dl_tasks_root); +} + +static int push_dl_task(struct rq *rq); + +#else + +static inline +void enqueue_pushable_dl_task(struct rq *rq, struct task_struct *p) +{ +} + +static inline +void dequeue_pushable_dl_task(struct rq *rq, struct task_struct *p) +{ +} + +static inline +void inc_dl_migration(struct sched_dl_entity *dl_se, struct dl_rq *dl_rq) +{ +} + +static inline +void dec_dl_migration(struct sched_dl_entity *dl_se, struct dl_rq *dl_rq) +{ +} + +#endif /* CONFIG_SMP */ + +static void enqueue_task_dl(struct rq *rq, struct task_struct *p, int flags); +static void __dequeue_task_dl(struct rq *rq, struct task_struct *p, int flags); +static void check_preempt_curr_dl(struct rq *rq, struct task_struct *p, + int flags); + +/* + * We are being explicitly informed that a new instance is starting, + * and this means that: + * - the absolute deadline of the entity has to be placed at + * current time + relative deadline; + * - the runtime of the entity has to be set to the maximum value. + * + * The capability of specifying such event is useful whenever a -deadline + * entity wants to (try to!) synchronize its behaviour with the scheduler's + * one, and to (try to!) reconcile itself with its own scheduling + * parameters. + */ +static inline void setup_new_dl_entity(struct sched_dl_entity *dl_se, + struct sched_dl_entity *pi_se) +{ + struct dl_rq *dl_rq = dl_rq_of_se(dl_se); + struct rq *rq = rq_of_dl_rq(dl_rq); + + WARN_ON(!dl_se->dl_new || dl_se->dl_throttled); + + /* + * We use the regular wall clock time to set deadlines in the + * future; in fact, we must consider execution overheads (time + * spent on hardirq context, etc.). + */ + dl_se->deadline = rq_clock(rq) + pi_se->dl_deadline; + dl_se->runtime = pi_se->dl_runtime; + dl_se->dl_new = 0; +} + +/* + * Pure Earliest Deadline First (EDF) scheduling does not deal with the + * possibility of a entity lasting more than what it declared, and thus + * exhausting its runtime. + * + * Here we are interested in making runtime overrun possible, but we do + * not want a entity which is misbehaving to affect the scheduling of all + * other entities. + * Therefore, a budgeting strategy called Constant Bandwidth Server (CBS) + * is used, in order to confine each entity within its own bandwidth. + * + * This function deals exactly with that, and ensures that when the runtime + * of a entity is replenished, its deadline is also postponed. That ensures + * the overrunning entity can't interfere with other entity in the system and + * can't make them miss their deadlines. Reasons why this kind of overruns + * could happen are, typically, a entity voluntarily trying to overcome its + * runtime, or it just underestimated it during sched_setscheduler_ex(). + */ +static void replenish_dl_entity(struct sched_dl_entity *dl_se, + struct sched_dl_entity *pi_se) +{ + struct dl_rq *dl_rq = dl_rq_of_se(dl_se); + struct rq *rq = rq_of_dl_rq(dl_rq); + + BUG_ON(pi_se->dl_runtime <= 0); + + /* + * This could be the case for a !-dl task that is boosted. + * Just go with full inherited parameters. + */ + if (dl_se->dl_deadline == 0) { + dl_se->deadline = rq_clock(rq) + pi_se->dl_deadline; + dl_se->runtime = pi_se->dl_runtime; + } + + /* + * We keep moving the deadline away until we get some + * available runtime for the entity. This ensures correct + * handling of situations where the runtime overrun is + * arbitrary large. + */ + while (dl_se->runtime <= 0) { + dl_se->deadline += pi_se->dl_period; + dl_se->runtime += pi_se->dl_runtime; + } + + /* + * At this point, the deadline really should be "in + * the future" with respect to rq->clock. If it's + * not, we are, for some reason, lagging too much! + * Anyway, after having warn userspace abut that, + * we still try to keep the things running by + * resetting the deadline and the budget of the + * entity. + */ + if (dl_time_before(dl_se->deadline, rq_clock(rq))) { + static bool lag_once = false; + + if (!lag_once) { + lag_once = true; + printk_sched("sched: DL replenish lagged to much\n"); + } + dl_se->deadline = rq_clock(rq) + pi_se->dl_deadline; + dl_se->runtime = pi_se->dl_runtime; + } +} + +/* + * Here we check if --at time t-- an entity (which is probably being + * [re]activated or, in general, enqueued) can use its remaining runtime + * and its current deadline _without_ exceeding the bandwidth it is + * assigned (function returns true if it can't). We are in fact applying + * one of the CBS rules: when a task wakes up, if the residual runtime + * over residual deadline fits within the allocated bandwidth, then we + * can keep the current (absolute) deadline and residual budget without + * disrupting the schedulability of the system. Otherwise, we should + * refill the runtime and set the deadline a period in the future, + * because keeping the current (absolute) deadline of the task would + * result in breaking guarantees promised to other tasks. + * + * This function returns true if: + * + * runtime / (deadline - t) > dl_runtime / dl_period , + * + * IOW we can't recycle current parameters. + * + * Notice that the bandwidth check is done against the period. For + * task with deadline equal to period this is the same of using + * dl_deadline instead of dl_period in the equation above. + */ +static bool dl_entity_overflow(struct sched_dl_entity *dl_se, + struct sched_dl_entity *pi_se, u64 t) +{ + u64 left, right; + + /* + * left and right are the two sides of the equation above, + * after a bit of shuffling to use multiplications instead + * of divisions. + * + * Note that none of the time values involved in the two + * multiplications are absolute: dl_deadline and dl_runtime + * are the relative deadline and the maximum runtime of each + * instance, runtime is the runtime left for the last instance + * and (deadline - t), since t is rq->clock, is the time left + * to the (absolute) deadline. Even if overflowing the u64 type + * is very unlikely to occur in both cases, here we scale down + * as we want to avoid that risk at all. Scaling down by 10 + * means that we reduce granularity to 1us. We are fine with it, + * since this is only a true/false check and, anyway, thinking + * of anything below microseconds resolution is actually fiction + * (but still we want to give the user that illusion >;). + */ + left = (pi_se->dl_period >> DL_SCALE) * (dl_se->runtime >> DL_SCALE); + right = ((dl_se->deadline - t) >> DL_SCALE) * + (pi_se->dl_runtime >> DL_SCALE); + + return dl_time_before(right, left); +} + +/* + * When a -deadline entity is queued back on the runqueue, its runtime and + * deadline might need updating. + * + * The policy here is that we update the deadline of the entity only if: + * - the current deadline is in the past, + * - using the remaining runtime with the current deadline would make + * the entity exceed its bandwidth. + */ +static void update_dl_entity(struct sched_dl_entity *dl_se, + struct sched_dl_entity *pi_se) +{ + struct dl_rq *dl_rq = dl_rq_of_se(dl_se); + struct rq *rq = rq_of_dl_rq(dl_rq); + + /* + * The arrival of a new instance needs special treatment, i.e., + * the actual scheduling parameters have to be "renewed". + */ + if (dl_se->dl_new) { + setup_new_dl_entity(dl_se, pi_se); + return; + } + + if (dl_time_before(dl_se->deadline, rq_clock(rq)) || + dl_entity_overflow(dl_se, pi_se, rq_clock(rq))) { + dl_se->deadline = rq_clock(rq) + pi_se->dl_deadline; + dl_se->runtime = pi_se->dl_runtime; + } +} + +/* + * If the entity depleted all its runtime, and if we want it to sleep + * while waiting for some new execution time to become available, we + * set the bandwidth enforcement timer to the replenishment instant + * and try to activate it. + * + * Notice that it is important for the caller to know if the timer + * actually started or not (i.e., the replenishment instant is in + * the future or in the past). + */ +static int start_dl_timer(struct sched_dl_entity *dl_se, bool boosted) +{ + struct dl_rq *dl_rq = dl_rq_of_se(dl_se); + struct rq *rq = rq_of_dl_rq(dl_rq); + ktime_t now, act; + ktime_t soft, hard; + unsigned long range; + s64 delta; + + if (boosted) + return 0; + /* + * We want the timer to fire at the deadline, but considering + * that it is actually coming from rq->clock and not from + * hrtimer's time base reading. + */ + act = ns_to_ktime(dl_se->deadline); + now = hrtimer_cb_get_time(&dl_se->dl_timer); + delta = ktime_to_ns(now) - rq_clock(rq); + act = ktime_add_ns(act, delta); + + /* + * If the expiry time already passed, e.g., because the value + * chosen as the deadline is too small, don't even try to + * start the timer in the past! + */ + if (ktime_us_delta(act, now) < 0) + return 0; + + hrtimer_set_expires(&dl_se->dl_timer, act); + + soft = hrtimer_get_softexpires(&dl_se->dl_timer); + hard = hrtimer_get_expires(&dl_se->dl_timer); + range = ktime_to_ns(ktime_sub(hard, soft)); + __hrtimer_start_range_ns(&dl_se->dl_timer, soft, + range, HRTIMER_MODE_ABS, 0); + + return hrtimer_active(&dl_se->dl_timer); +} + +/* + * This is the bandwidth enforcement timer callback. If here, we know + * a task is not on its dl_rq, since the fact that the timer was running + * means the task is throttled and needs a runtime replenishment. + * + * However, what we actually do depends on the fact the task is active, + * (it is on its rq) or has been removed from there by a call to + * dequeue_task_dl(). In the former case we must issue the runtime + * replenishment and add the task back to the dl_rq; in the latter, we just + * do nothing but clearing dl_throttled, so that runtime and deadline + * updating (and the queueing back to dl_rq) will be done by the + * next call to enqueue_task_dl(). + */ +static enum hrtimer_restart dl_task_timer(struct hrtimer *timer) +{ + struct sched_dl_entity *dl_se = container_of(timer, + struct sched_dl_entity, + dl_timer); + struct task_struct *p = dl_task_of(dl_se); + struct rq *rq = task_rq(p); + raw_spin_lock(&rq->lock); + + /* + * We need to take care of a possible races here. In fact, the + * task might have changed its scheduling policy to something + * different from SCHED_DEADLINE or changed its reservation + * parameters (through sched_setscheduler()). + */ + if (!dl_task(p) || dl_se->dl_new) + goto unlock; + + sched_clock_tick(); + update_rq_clock(rq); + dl_se->dl_throttled = 0; + if (p->on_rq) { + enqueue_task_dl(rq, p, ENQUEUE_REPLENISH); + if (task_has_dl_policy(rq->curr)) + check_preempt_curr_dl(rq, p, 0); + else + resched_task(rq->curr); +#ifdef CONFIG_SMP + /* + * Queueing this task back might have overloaded rq, + * check if we need to kick someone away. + */ + if (has_pushable_dl_tasks(rq)) + push_dl_task(rq); +#endif + } +unlock: + raw_spin_unlock(&rq->lock); + + return HRTIMER_NORESTART; +} + +void init_dl_task_timer(struct sched_dl_entity *dl_se) +{ + struct hrtimer *timer = &dl_se->dl_timer; + + if (hrtimer_active(timer)) { + hrtimer_try_to_cancel(timer); + return; + } + + hrtimer_init(timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); + timer->function = dl_task_timer; +} + +static +int dl_runtime_exceeded(struct rq *rq, struct sched_dl_entity *dl_se) +{ + int dmiss = dl_time_before(dl_se->deadline, rq_clock(rq)); + int rorun = dl_se->runtime <= 0; + + if (!rorun && !dmiss) + return 0; + + /* + * If we are beyond our current deadline and we are still + * executing, then we have already used some of the runtime of + * the next instance. Thus, if we do not account that, we are + * stealing bandwidth from the system at each deadline miss! + */ + if (dmiss) { + dl_se->runtime = rorun ? dl_se->runtime : 0; + dl_se->runtime -= rq_clock(rq) - dl_se->deadline; + } + + return 1; +} + +/* + * Update the current task's runtime statistics (provided it is still + * a -deadline task and has not been removed from the dl_rq). + */ +static void update_curr_dl(struct rq *rq) +{ + struct task_struct *curr = rq->curr; + struct sched_dl_entity *dl_se = &curr->dl; + u64 delta_exec; + + if (!dl_task(curr) || !on_dl_rq(dl_se)) + return; + + /* + * Consumed budget is computed considering the time as + * observed by schedulable tasks (excluding time spent + * in hardirq context, etc.). Deadlines are instead + * computed using hard walltime. This seems to be the more + * natural solution, but the full ramifications of this + * approach need further study. + */ + delta_exec = rq_clock_task(rq) - curr->se.exec_start; + if (unlikely((s64)delta_exec < 0)) + delta_exec = 0; + + schedstat_set(curr->se.statistics.exec_max, + max(curr->se.statistics.exec_max, delta_exec)); + + curr->se.sum_exec_runtime += delta_exec; + account_group_exec_runtime(curr, delta_exec); + + curr->se.exec_start = rq_clock_task(rq); + cpuacct_charge(curr, delta_exec); + + sched_rt_avg_update(rq, delta_exec); + + dl_se->runtime -= delta_exec; + if (dl_runtime_exceeded(rq, dl_se)) { + __dequeue_task_dl(rq, curr, 0); + if (likely(start_dl_timer(dl_se, curr->dl.dl_boosted))) + dl_se->dl_throttled = 1; + else + enqueue_task_dl(rq, curr, ENQUEUE_REPLENISH); + + if (!is_leftmost(curr, &rq->dl)) + resched_task(curr); + } + + /* + * Because -- for now -- we share the rt bandwidth, we need to + * account our runtime there too, otherwise actual rt tasks + * would be able to exceed the shared quota. + * + * Account to the root rt group for now. + * + * The solution we're working towards is having the RT groups scheduled + * using deadline servers -- however there's a few nasties to figure + * out before that can happen. + */ + if (rt_bandwidth_enabled()) { + struct rt_rq *rt_rq = &rq->rt; + + raw_spin_lock(&rt_rq->rt_runtime_lock); + rt_rq->rt_time += delta_exec; + /* + * We'll let actual RT tasks worry about the overflow here, we + * have our own CBS to keep us inline -- see above. + */ + raw_spin_unlock(&rt_rq->rt_runtime_lock); + } +} + +#ifdef CONFIG_SMP + +static struct task_struct *pick_next_earliest_dl_task(struct rq *rq, int cpu); + +static inline u64 next_deadline(struct rq *rq) +{ + struct task_struct *next = pick_next_earliest_dl_task(rq, rq->cpu); + + if (next && dl_prio(next->prio)) + return next->dl.deadline; + else + return 0; +} + +static void inc_dl_deadline(struct dl_rq *dl_rq, u64 deadline) +{ + struct rq *rq = rq_of_dl_rq(dl_rq); + + if (dl_rq->earliest_dl.curr == 0 || + dl_time_before(deadline, dl_rq->earliest_dl.curr)) { + /* + * If the dl_rq had no -deadline tasks, or if the new task + * has shorter deadline than the current one on dl_rq, we + * know that the previous earliest becomes our next earliest, + * as the new task becomes the earliest itself. + */ + dl_rq->earliest_dl.next = dl_rq->earliest_dl.curr; + dl_rq->earliest_dl.curr = deadline; + cpudl_set(&rq->rd->cpudl, rq->cpu, deadline, 1); + } else if (dl_rq->earliest_dl.next == 0 || + dl_time_before(deadline, dl_rq->earliest_dl.next)) { + /* + * On the other hand, if the new -deadline task has a + * a later deadline than the earliest one on dl_rq, but + * it is earlier than the next (if any), we must + * recompute the next-earliest. + */ + dl_rq->earliest_dl.next = next_deadline(rq); + } +} + +static void dec_dl_deadline(struct dl_rq *dl_rq, u64 deadline) +{ + struct rq *rq = rq_of_dl_rq(dl_rq); + + /* + * Since we may have removed our earliest (and/or next earliest) + * task we must recompute them. + */ + if (!dl_rq->dl_nr_running) { + dl_rq->earliest_dl.curr = 0; + dl_rq->earliest_dl.next = 0; + cpudl_set(&rq->rd->cpudl, rq->cpu, 0, 0); + } else { + struct rb_node *leftmost = dl_rq->rb_leftmost; + struct sched_dl_entity *entry; + + entry = rb_entry(leftmost, struct sched_dl_entity, rb_node); + dl_rq->earliest_dl.curr = entry->deadline; + dl_rq->earliest_dl.next = next_deadline(rq); + cpudl_set(&rq->rd->cpudl, rq->cpu, entry->deadline, 1); + } +} + +#else + +static inline void inc_dl_deadline(struct dl_rq *dl_rq, u64 deadline) {} +static inline void dec_dl_deadline(struct dl_rq *dl_rq, u64 deadline) {} + +#endif /* CONFIG_SMP */ + +static inline +void inc_dl_tasks(struct sched_dl_entity *dl_se, struct dl_rq *dl_rq) +{ + int prio = dl_task_of(dl_se)->prio; + u64 deadline = dl_se->deadline; + + WARN_ON(!dl_prio(prio)); + dl_rq->dl_nr_running++; + + inc_dl_deadline(dl_rq, deadline); + inc_dl_migration(dl_se, dl_rq); +} + +static inline +void dec_dl_tasks(struct sched_dl_entity *dl_se, struct dl_rq *dl_rq) +{ + int prio = dl_task_of(dl_se)->prio; + + WARN_ON(!dl_prio(prio)); + WARN_ON(!dl_rq->dl_nr_running); + dl_rq->dl_nr_running--; + + dec_dl_deadline(dl_rq, dl_se->deadline); + dec_dl_migration(dl_se, dl_rq); +} + +static void __enqueue_dl_entity(struct sched_dl_entity *dl_se) +{ + struct dl_rq *dl_rq = dl_rq_of_se(dl_se); + struct rb_node **link = &dl_rq->rb_root.rb_node; + struct rb_node *parent = NULL; + struct sched_dl_entity *entry; + int leftmost = 1; + + BUG_ON(!RB_EMPTY_NODE(&dl_se->rb_node)); + + while (*link) { + parent = *link; + entry = rb_entry(parent, struct sched_dl_entity, rb_node); + if (dl_time_before(dl_se->deadline, entry->deadline)) + link = &parent->rb_left; + else { + link = &parent->rb_right; + leftmost = 0; + } + } + + if (leftmost) + dl_rq->rb_leftmost = &dl_se->rb_node; + + rb_link_node(&dl_se->rb_node, parent, link); + rb_insert_color(&dl_se->rb_node, &dl_rq->rb_root); + + inc_dl_tasks(dl_se, dl_rq); +} + +static void __dequeue_dl_entity(struct sched_dl_entity *dl_se) +{ + struct dl_rq *dl_rq = dl_rq_of_se(dl_se); + + if (RB_EMPTY_NODE(&dl_se->rb_node)) + return; + + if (dl_rq->rb_leftmost == &dl_se->rb_node) { + struct rb_node *next_node; + + next_node = rb_next(&dl_se->rb_node); + dl_rq->rb_leftmost = next_node; + } + + rb_erase(&dl_se->rb_node, &dl_rq->rb_root); + RB_CLEAR_NODE(&dl_se->rb_node); + + dec_dl_tasks(dl_se, dl_rq); +} + +static void +enqueue_dl_entity(struct sched_dl_entity *dl_se, + struct sched_dl_entity *pi_se, int flags) +{ + BUG_ON(on_dl_rq(dl_se)); + + /* + * If this is a wakeup or a new instance, the scheduling + * parameters of the task might need updating. Otherwise, + * we want a replenishment of its runtime. + */ + if (!dl_se->dl_new && flags & ENQUEUE_REPLENISH) + replenish_dl_entity(dl_se, pi_se); + else + update_dl_entity(dl_se, pi_se); + + __enqueue_dl_entity(dl_se); +} + +static void dequeue_dl_entity(struct sched_dl_entity *dl_se) +{ + __dequeue_dl_entity(dl_se); +} + +static void enqueue_task_dl(struct rq *rq, struct task_struct *p, int flags) +{ + struct task_struct *pi_task = rt_mutex_get_top_task(p); + struct sched_dl_entity *pi_se = &p->dl; + + /* + * Use the scheduling parameters of the top pi-waiter + * task if we have one and its (relative) deadline is + * smaller than our one... OTW we keep our runtime and + * deadline. + */ + if (pi_task && p->dl.dl_boosted && dl_prio(pi_task->normal_prio)) + pi_se = &pi_task->dl; + + /* + * If p is throttled, we do nothing. In fact, if it exhausted + * its budget it needs a replenishment and, since it now is on + * its rq, the bandwidth timer callback (which clearly has not + * run yet) will take care of this. + */ + if (p->dl.dl_throttled) + return; + + enqueue_dl_entity(&p->dl, pi_se, flags); + + if (!task_current(rq, p) && p->nr_cpus_allowed > 1) + enqueue_pushable_dl_task(rq, p); + + inc_nr_running(rq); +} + +static void __dequeue_task_dl(struct rq *rq, struct task_struct *p, int flags) +{ + dequeue_dl_entity(&p->dl); + dequeue_pushable_dl_task(rq, p); +} + +static void dequeue_task_dl(struct rq *rq, struct task_struct *p, int flags) +{ + update_curr_dl(rq); + __dequeue_task_dl(rq, p, flags); + + dec_nr_running(rq); +} + +/* + * Yield task semantic for -deadline tasks is: + * + * get off from the CPU until our next instance, with + * a new runtime. This is of little use now, since we + * don't have a bandwidth reclaiming mechanism. Anyway, + * bandwidth reclaiming is planned for the future, and + * yield_task_dl will indicate that some spare budget + * is available for other task instances to use it. + */ +static void yield_task_dl(struct rq *rq) +{ + struct task_struct *p = rq->curr; + + /* + * We make the task go to sleep until its current deadline by + * forcing its runtime to zero. This way, update_curr_dl() stops + * it and the bandwidth timer will wake it up and will give it + * new scheduling parameters (thanks to dl_new=1). + */ + if (p->dl.runtime > 0) { + rq->curr->dl.dl_new = 1; + p->dl.runtime = 0; + } + update_curr_dl(rq); +} + +#ifdef CONFIG_SMP + +static int find_later_rq(struct task_struct *task); + +static int +select_task_rq_dl(struct task_struct *p, int cpu, int sd_flag, int flags) +{ + struct task_struct *curr; + struct rq *rq; + + if (sd_flag != SD_BALANCE_WAKE && sd_flag != SD_BALANCE_FORK) + goto out; + + rq = cpu_rq(cpu); + + rcu_read_lock(); + curr = ACCESS_ONCE(rq->curr); /* unlocked access */ + + /* + * If we are dealing with a -deadline task, we must + * decide where to wake it up. + * If it has a later deadline and the current task + * on this rq can't move (provided the waking task + * can!) we prefer to send it somewhere else. On the + * other hand, if it has a shorter deadline, we + * try to make it stay here, it might be important. + */ + if (unlikely(dl_task(curr)) && + (curr->nr_cpus_allowed < 2 || + !dl_entity_preempt(&p->dl, &curr->dl)) && + (p->nr_cpus_allowed > 1)) { + int target = find_later_rq(p); + + if (target != -1) + cpu = target; + } + rcu_read_unlock(); + +out: + return cpu; +} + +static void check_preempt_equal_dl(struct rq *rq, struct task_struct *p) +{ + /* + * Current can't be migrated, useless to reschedule, + * let's hope p can move out. + */ + if (rq->curr->nr_cpus_allowed == 1 || + cpudl_find(&rq->rd->cpudl, rq->curr, NULL) == -1) + return; + + /* + * p is migratable, so let's not schedule it and + * see if it is pushed or pulled somewhere else. + */ + if (p->nr_cpus_allowed != 1 && + cpudl_find(&rq->rd->cpudl, p, NULL) != -1) + return; + + resched_task(rq->curr); +} + +#endif /* CONFIG_SMP */ + +/* + * Only called when both the current and waking task are -deadline + * tasks. + */ +static void check_preempt_curr_dl(struct rq *rq, struct task_struct *p, + int flags) +{ + if (dl_entity_preempt(&p->dl, &rq->curr->dl)) { + resched_task(rq->curr); + return; + } + +#ifdef CONFIG_SMP + /* + * In the unlikely case current and p have the same deadline + * let us try to decide what's the best thing to do... + */ + if ((p->dl.deadline == rq->curr->dl.deadline) && + !test_tsk_need_resched(rq->curr)) + check_preempt_equal_dl(rq, p); +#endif /* CONFIG_SMP */ +} + +#ifdef CONFIG_SCHED_HRTICK +static void start_hrtick_dl(struct rq *rq, struct task_struct *p) +{ + s64 delta = p->dl.dl_runtime - p->dl.runtime; + + if (delta > 10000) + hrtick_start(rq, p->dl.runtime); +} +#endif + +static struct sched_dl_entity *pick_next_dl_entity(struct rq *rq, + struct dl_rq *dl_rq) +{ + struct rb_node *left = dl_rq->rb_leftmost; + + if (!left) + return NULL; + + return rb_entry(left, struct sched_dl_entity, rb_node); +} + +struct task_struct *pick_next_task_dl(struct rq *rq) +{ + struct sched_dl_entity *dl_se; + struct task_struct *p; + struct dl_rq *dl_rq; + + dl_rq = &rq->dl; + + if (unlikely(!dl_rq->dl_nr_running)) + return NULL; + + dl_se = pick_next_dl_entity(rq, dl_rq); + BUG_ON(!dl_se); + + p = dl_task_of(dl_se); + p->se.exec_start = rq_clock_task(rq); + + /* Running task will never be pushed. */ + dequeue_pushable_dl_task(rq, p); + +#ifdef CONFIG_SCHED_HRTICK + if (hrtick_enabled(rq)) + start_hrtick_dl(rq, p); +#endif + +#ifdef CONFIG_SMP + rq->post_schedule = has_pushable_dl_tasks(rq); +#endif /* CONFIG_SMP */ + + return p; +} + +static void put_prev_task_dl(struct rq *rq, struct task_struct *p) +{ + update_curr_dl(rq); + + if (on_dl_rq(&p->dl) && p->nr_cpus_allowed > 1) + enqueue_pushable_dl_task(rq, p); +} + +static void task_tick_dl(struct rq *rq, struct task_struct *p, int queued) +{ + update_curr_dl(rq); + +#ifdef CONFIG_SCHED_HRTICK + if (hrtick_enabled(rq) && queued && p->dl.runtime > 0) + start_hrtick_dl(rq, p); +#endif +} + +static void task_fork_dl(struct task_struct *p) +{ + /* + * SCHED_DEADLINE tasks cannot fork and this is achieved through + * sched_fork() + */ +} + +static void task_dead_dl(struct task_struct *p) +{ + struct hrtimer *timer = &p->dl.dl_timer; + struct dl_bw *dl_b = dl_bw_of(task_cpu(p)); + + /* + * Since we are TASK_DEAD we won't slip out of the domain! + */ + raw_spin_lock_irq(&dl_b->lock); + dl_b->total_bw -= p->dl.dl_bw; + raw_spin_unlock_irq(&dl_b->lock); + + hrtimer_cancel(timer); +} + +static void set_curr_task_dl(struct rq *rq) +{ + struct task_struct *p = rq->curr; + + p->se.exec_start = rq_clock_task(rq); + + /* You can't push away the running task */ + dequeue_pushable_dl_task(rq, p); +} + +#ifdef CONFIG_SMP + +/* Only try algorithms three times */ +#define DL_MAX_TRIES 3 + +static int pick_dl_task(struct rq *rq, struct task_struct *p, int cpu) +{ + if (!task_running(rq, p) && + (cpu < 0 || cpumask_test_cpu(cpu, &p->cpus_allowed)) && + (p->nr_cpus_allowed > 1)) + return 1; + + return 0; +} + +/* Returns the second earliest -deadline task, NULL otherwise */ +static struct task_struct *pick_next_earliest_dl_task(struct rq *rq, int cpu) +{ + struct rb_node *next_node = rq->dl.rb_leftmost; + struct sched_dl_entity *dl_se; + struct task_struct *p = NULL; + +next_node: + next_node = rb_next(next_node); + if (next_node) { + dl_se = rb_entry(next_node, struct sched_dl_entity, rb_node); + p = dl_task_of(dl_se); + + if (pick_dl_task(rq, p, cpu)) + return p; + + goto next_node; + } + + return NULL; +} + +static DEFINE_PER_CPU(cpumask_var_t, local_cpu_mask_dl); + +static int find_later_rq(struct task_struct *task) +{ + struct sched_domain *sd; + struct cpumask *later_mask = __get_cpu_var(local_cpu_mask_dl); + int this_cpu = smp_processor_id(); + int best_cpu, cpu = task_cpu(task); + + /* Make sure the mask is initialized first */ + if (unlikely(!later_mask)) + return -1; + + if (task->nr_cpus_allowed == 1) + return -1; + + best_cpu = cpudl_find(&task_rq(task)->rd->cpudl, + task, later_mask); + if (best_cpu == -1) + return -1; + + /* + * If we are here, some target has been found, + * the most suitable of which is cached in best_cpu. + * This is, among the runqueues where the current tasks + * have later deadlines than the task's one, the rq + * with the latest possible one. + * + * Now we check how well this matches with task's + * affinity and system topology. + * + * The last cpu where the task run is our first + * guess, since it is most likely cache-hot there. + */ + if (cpumask_test_cpu(cpu, later_mask)) + return cpu; + /* + * Check if this_cpu is to be skipped (i.e., it is + * not in the mask) or not. + */ + if (!cpumask_test_cpu(this_cpu, later_mask)) + this_cpu = -1; + + rcu_read_lock(); + for_each_domain(cpu, sd) { + if (sd->flags & SD_WAKE_AFFINE) { + + /* + * If possible, preempting this_cpu is + * cheaper than migrating. + */ + if (this_cpu != -1 && + cpumask_test_cpu(this_cpu, sched_domain_span(sd))) { + rcu_read_unlock(); + return this_cpu; + } + + /* + * Last chance: if best_cpu is valid and is + * in the mask, that becomes our choice. + */ + if (best_cpu < nr_cpu_ids && + cpumask_test_cpu(best_cpu, sched_domain_span(sd))) { + rcu_read_unlock(); + return best_cpu; + } + } + } + rcu_read_unlock(); + + /* + * At this point, all our guesses failed, we just return + * 'something', and let the caller sort the things out. + */ + if (this_cpu != -1) + return this_cpu; + + cpu = cpumask_any(later_mask); + if (cpu < nr_cpu_ids) + return cpu; + + return -1; +} + +/* Locks the rq it finds */ +static struct rq *find_lock_later_rq(struct task_struct *task, struct rq *rq) +{ + struct rq *later_rq = NULL; + int tries; + int cpu; + + for (tries = 0; tries < DL_MAX_TRIES; tries++) { + cpu = find_later_rq(task); + + if ((cpu == -1) || (cpu == rq->cpu)) + break; + + later_rq = cpu_rq(cpu); + + /* Retry if something changed. */ + if (double_lock_balance(rq, later_rq)) { + if (unlikely(task_rq(task) != rq || + !cpumask_test_cpu(later_rq->cpu, + &task->cpus_allowed) || + task_running(rq, task) || !task->on_rq)) { + double_unlock_balance(rq, later_rq); + later_rq = NULL; + break; + } + } + + /* + * If the rq we found has no -deadline task, or + * its earliest one has a later deadline than our + * task, the rq is a good one. + */ + if (!later_rq->dl.dl_nr_running || + dl_time_before(task->dl.deadline, + later_rq->dl.earliest_dl.curr)) + break; + + /* Otherwise we try again. */ + double_unlock_balance(rq, later_rq); + later_rq = NULL; + } + + return later_rq; +} + +static struct task_struct *pick_next_pushable_dl_task(struct rq *rq) +{ + struct task_struct *p; + + if (!has_pushable_dl_tasks(rq)) + return NULL; + + p = rb_entry(rq->dl.pushable_dl_tasks_leftmost, + struct task_struct, pushable_dl_tasks); + + BUG_ON(rq->cpu != task_cpu(p)); + BUG_ON(task_current(rq, p)); + BUG_ON(p->nr_cpus_allowed <= 1); + + BUG_ON(!p->on_rq); + BUG_ON(!dl_task(p)); + + return p; +} + +/* + * See if the non running -deadline tasks on this rq + * can be sent to some other CPU where they can preempt + * and start executing. + */ +static int push_dl_task(struct rq *rq) +{ + struct task_struct *next_task; + struct rq *later_rq; + + if (!rq->dl.overloaded) + return 0; + + next_task = pick_next_pushable_dl_task(rq); + if (!next_task) + return 0; + +retry: + if (unlikely(next_task == rq->curr)) { + WARN_ON(1); + return 0; + } + + /* + * If next_task preempts rq->curr, and rq->curr + * can move away, it makes sense to just reschedule + * without going further in pushing next_task. + */ + if (dl_task(rq->curr) && + dl_time_before(next_task->dl.deadline, rq->curr->dl.deadline) && + rq->curr->nr_cpus_allowed > 1) { + resched_task(rq->curr); + return 0; + } + + /* We might release rq lock */ + get_task_struct(next_task); + + /* Will lock the rq it'll find */ + later_rq = find_lock_later_rq(next_task, rq); + if (!later_rq) { + struct task_struct *task; + + /* + * We must check all this again, since + * find_lock_later_rq releases rq->lock and it is + * then possible that next_task has migrated. + */ + task = pick_next_pushable_dl_task(rq); + if (task_cpu(next_task) == rq->cpu && task == next_task) { + /* + * The task is still there. We don't try + * again, some other cpu will pull it when ready. + */ + dequeue_pushable_dl_task(rq, next_task); + goto out; + } + + if (!task) + /* No more tasks */ + goto out; + + put_task_struct(next_task); + next_task = task; + goto retry; + } + + deactivate_task(rq, next_task, 0); + set_task_cpu(next_task, later_rq->cpu); + activate_task(later_rq, next_task, 0); + + resched_task(later_rq->curr); + + double_unlock_balance(rq, later_rq); + +out: + put_task_struct(next_task); + + return 1; +} + +static void push_dl_tasks(struct rq *rq) +{ + /* Terminates as it moves a -deadline task */ + while (push_dl_task(rq)) + ; +} + +static int pull_dl_task(struct rq *this_rq) +{ + int this_cpu = this_rq->cpu, ret = 0, cpu; + struct task_struct *p; + struct rq *src_rq; + u64 dmin = LONG_MAX; + + if (likely(!dl_overloaded(this_rq))) + return 0; + + /* + * Match the barrier from dl_set_overloaded; this guarantees that if we + * see overloaded we must also see the dlo_mask bit. + */ + smp_rmb(); + + for_each_cpu(cpu, this_rq->rd->dlo_mask) { + if (this_cpu == cpu) + continue; + + src_rq = cpu_rq(cpu); + + /* + * It looks racy, abd it is! However, as in sched_rt.c, + * we are fine with this. + */ + if (this_rq->dl.dl_nr_running && + dl_time_before(this_rq->dl.earliest_dl.curr, + src_rq->dl.earliest_dl.next)) + continue; + + /* Might drop this_rq->lock */ + double_lock_balance(this_rq, src_rq); + + /* + * If there are no more pullable tasks on the + * rq, we're done with it. + */ + if (src_rq->dl.dl_nr_running <= 1) + goto skip; + + p = pick_next_earliest_dl_task(src_rq, this_cpu); + + /* + * We found a task to be pulled if: + * - it preempts our current (if there's one), + * - it will preempt the last one we pulled (if any). + */ + if (p && dl_time_before(p->dl.deadline, dmin) && + (!this_rq->dl.dl_nr_running || + dl_time_before(p->dl.deadline, + this_rq->dl.earliest_dl.curr))) { + WARN_ON(p == src_rq->curr); + WARN_ON(!p->on_rq); + + /* + * Then we pull iff p has actually an earlier + * deadline than the current task of its runqueue. + */ + if (dl_time_before(p->dl.deadline, + src_rq->curr->dl.deadline)) + goto skip; + + ret = 1; + + deactivate_task(src_rq, p, 0); + set_task_cpu(p, this_cpu); + activate_task(this_rq, p, 0); + dmin = p->dl.deadline; + + /* Is there any other task even earlier? */ + } +skip: + double_unlock_balance(this_rq, src_rq); + } + + return ret; +} + +static void pre_schedule_dl(struct rq *rq, struct task_struct *prev) +{ + /* Try to pull other tasks here */ + if (dl_task(prev)) + pull_dl_task(rq); +} + +static void post_schedule_dl(struct rq *rq) +{ + push_dl_tasks(rq); +} + +/* + * Since the task is not running and a reschedule is not going to happen + * anytime soon on its runqueue, we try pushing it away now. + */ +static void task_woken_dl(struct rq *rq, struct task_struct *p) +{ + if (!task_running(rq, p) && + !test_tsk_need_resched(rq->curr) && + has_pushable_dl_tasks(rq) && + p->nr_cpus_allowed > 1 && + dl_task(rq->curr) && + (rq->curr->nr_cpus_allowed < 2 || + dl_entity_preempt(&rq->curr->dl, &p->dl))) { + push_dl_tasks(rq); + } +} + +static void set_cpus_allowed_dl(struct task_struct *p, + const struct cpumask *new_mask) +{ + struct rq *rq; + int weight; + + BUG_ON(!dl_task(p)); + + /* + * Update only if the task is actually running (i.e., + * it is on the rq AND it is not throttled). + */ + if (!on_dl_rq(&p->dl)) + return; + + weight = cpumask_weight(new_mask); + + /* + * Only update if the process changes its state from whether it + * can migrate or not. + */ + if ((p->nr_cpus_allowed > 1) == (weight > 1)) + return; + + rq = task_rq(p); + + /* + * The process used to be able to migrate OR it can now migrate + */ + if (weight <= 1) { + if (!task_current(rq, p)) + dequeue_pushable_dl_task(rq, p); + BUG_ON(!rq->dl.dl_nr_migratory); + rq->dl.dl_nr_migratory--; + } else { + if (!task_current(rq, p)) + enqueue_pushable_dl_task(rq, p); + rq->dl.dl_nr_migratory++; + } + + update_dl_migration(&rq->dl); +} + +/* Assumes rq->lock is held */ +static void rq_online_dl(struct rq *rq) +{ + if (rq->dl.overloaded) + dl_set_overload(rq); + + if (rq->dl.dl_nr_running > 0) + cpudl_set(&rq->rd->cpudl, rq->cpu, rq->dl.earliest_dl.curr, 1); +} + +/* Assumes rq->lock is held */ +static void rq_offline_dl(struct rq *rq) +{ + if (rq->dl.overloaded) + dl_clear_overload(rq); + + cpudl_set(&rq->rd->cpudl, rq->cpu, 0, 0); +} + +void init_sched_dl_class(void) +{ + unsigned int i; + + for_each_possible_cpu(i) + zalloc_cpumask_var_node(&per_cpu(local_cpu_mask_dl, i), + GFP_KERNEL, cpu_to_node(i)); +} + +#endif /* CONFIG_SMP */ + +static void switched_from_dl(struct rq *rq, struct task_struct *p) +{ + if (hrtimer_active(&p->dl.dl_timer) && !dl_policy(p->policy)) + hrtimer_try_to_cancel(&p->dl.dl_timer); + +#ifdef CONFIG_SMP + /* + * Since this might be the only -deadline task on the rq, + * this is the right place to try to pull some other one + * from an overloaded cpu, if any. + */ + if (!rq->dl.dl_nr_running) + pull_dl_task(rq); +#endif +} + +/* + * When switching to -deadline, we may overload the rq, then + * we try to push someone off, if possible. + */ +static void switched_to_dl(struct rq *rq, struct task_struct *p) +{ + int check_resched = 1; + + /* + * If p is throttled, don't consider the possibility + * of preempting rq->curr, the check will be done right + * after its runtime will get replenished. + */ + if (unlikely(p->dl.dl_throttled)) + return; + + if (p->on_rq || rq->curr != p) { +#ifdef CONFIG_SMP + if (rq->dl.overloaded && push_dl_task(rq) && rq != task_rq(p)) + /* Only reschedule if pushing failed */ + check_resched = 0; +#endif /* CONFIG_SMP */ + if (check_resched && task_has_dl_policy(rq->curr)) + check_preempt_curr_dl(rq, p, 0); + } +} + +/* + * If the scheduling parameters of a -deadline task changed, + * a push or pull operation might be needed. + */ +static void prio_changed_dl(struct rq *rq, struct task_struct *p, + int oldprio) +{ + if (p->on_rq || rq->curr == p) { +#ifdef CONFIG_SMP + /* + * This might be too much, but unfortunately + * we don't have the old deadline value, and + * we can't argue if the task is increasing + * or lowering its prio, so... + */ + if (!rq->dl.overloaded) + pull_dl_task(rq); + + /* + * If we now have a earlier deadline task than p, + * then reschedule, provided p is still on this + * runqueue. + */ + if (dl_time_before(rq->dl.earliest_dl.curr, p->dl.deadline) && + rq->curr == p) + resched_task(p); +#else + /* + * Again, we don't know if p has a earlier + * or later deadline, so let's blindly set a + * (maybe not needed) rescheduling point. + */ + resched_task(p); +#endif /* CONFIG_SMP */ + } else + switched_to_dl(rq, p); +} + +const struct sched_class dl_sched_class = { + .next = &rt_sched_class, + .enqueue_task = enqueue_task_dl, + .dequeue_task = dequeue_task_dl, + .yield_task = yield_task_dl, + + .check_preempt_curr = check_preempt_curr_dl, + + .pick_next_task = pick_next_task_dl, + .put_prev_task = put_prev_task_dl, + +#ifdef CONFIG_SMP + .select_task_rq = select_task_rq_dl, + .set_cpus_allowed = set_cpus_allowed_dl, + .rq_online = rq_online_dl, + .rq_offline = rq_offline_dl, + .pre_schedule = pre_schedule_dl, + .post_schedule = post_schedule_dl, + .task_woken = task_woken_dl, +#endif + + .set_curr_task = set_curr_task_dl, + .task_tick = task_tick_dl, + .task_fork = task_fork_dl, + .task_dead = task_dead_dl, + + .prio_changed = prio_changed_dl, + .switched_from = switched_from_dl, + .switched_to = switched_to_dl, +}; diff --git a/kernel/sched/debug.c b/kernel/sched/debug.c index 5c34d1817e8f..dd52e7ffb10e 100644 --- a/kernel/sched/debug.c +++ b/kernel/sched/debug.c @@ -139,7 +139,7 @@ print_task(struct seq_file *m, struct rq *rq, struct task_struct *p) 0LL, 0LL, 0LL, 0L, 0LL, 0L, 0LL, 0L); #endif #ifdef CONFIG_NUMA_BALANCING - SEQ_printf(m, " %d", cpu_to_node(task_cpu(p))); + SEQ_printf(m, " %d", task_node(p)); #endif #ifdef CONFIG_CGROUP_SCHED SEQ_printf(m, " %s", task_group_path(task_group(p))); @@ -371,7 +371,7 @@ static void sched_debug_header(struct seq_file *m) PN(cpu_clk); P(jiffies); #ifdef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK - P(sched_clock_stable); + P(sched_clock_stable()); #endif #undef PN #undef P diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index c7395d97e4cb..867b0a4b0893 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -872,15 +872,6 @@ static unsigned int task_scan_max(struct task_struct *p) return max(smin, smax); } -/* - * Once a preferred node is selected the scheduler balancer will prefer moving - * a task to that node for sysctl_numa_balancing_settle_count number of PTE - * scans. This will give the process the chance to accumulate more faults on - * the preferred node but still allow the scheduler to move the task again if - * the nodes CPUs are overloaded. - */ -unsigned int sysctl_numa_balancing_settle_count __read_mostly = 4; - static void account_numa_enqueue(struct rq *rq, struct task_struct *p) { rq->nr_numa_running += (p->numa_preferred_nid != -1); @@ -930,7 +921,8 @@ static inline unsigned long group_faults(struct task_struct *p, int nid) if (!p->numa_group) return 0; - return p->numa_group->faults[2*nid] + p->numa_group->faults[2*nid+1]; + return p->numa_group->faults[task_faults_idx(nid, 0)] + + p->numa_group->faults[task_faults_idx(nid, 1)]; } /* @@ -1023,7 +1015,7 @@ struct task_numa_env { struct numa_stats src_stats, dst_stats; - int imbalance_pct, idx; + int imbalance_pct; struct task_struct *best_task; long best_imp; @@ -1211,7 +1203,7 @@ static int task_numa_migrate(struct task_struct *p) * elsewhere, so there is no point in (re)trying. */ if (unlikely(!sd)) { - p->numa_preferred_nid = cpu_to_node(task_cpu(p)); + p->numa_preferred_nid = task_node(p); return -EINVAL; } @@ -1258,11 +1250,15 @@ static int task_numa_migrate(struct task_struct *p) p->numa_scan_period = task_scan_min(p); if (env.best_task == NULL) { - int ret = migrate_task_to(p, env.best_cpu); + ret = migrate_task_to(p, env.best_cpu); + if (ret != 0) + trace_sched_stick_numa(p, env.src_cpu, env.best_cpu); return ret; } ret = migrate_swap(p, env.best_task); + if (ret != 0) + trace_sched_stick_numa(p, env.src_cpu, task_cpu(env.best_task)); put_task_struct(env.best_task); return ret; } @@ -1278,7 +1274,7 @@ static void numa_migrate_preferred(struct task_struct *p) p->numa_migrate_retry = jiffies + HZ; /* Success if task is already running on preferred CPU */ - if (cpu_to_node(task_cpu(p)) == p->numa_preferred_nid) + if (task_node(p) == p->numa_preferred_nid) return; /* Otherwise, try migrate to a CPU on the preferred node */ @@ -1350,7 +1346,6 @@ static void update_task_scan_period(struct task_struct *p, * scanning faster if shared accesses dominate as it may * simply bounce migrations uselessly */ - period_slot = DIV_ROUND_UP(diff, NUMA_PERIOD_SLOTS); ratio = DIV_ROUND_UP(private * NUMA_PERIOD_SLOTS, (private + shared)); diff = (diff * ratio) / NUMA_PERIOD_SLOTS; } @@ -3923,7 +3918,7 @@ static long effective_load(struct task_group *tg, int cpu, long wl, long wg) { struct sched_entity *se = tg->se[cpu]; - if (!tg->parent || !wl) /* the trivial, non-cgroup case */ + if (!tg->parent) /* the trivial, non-cgroup case */ return wl; for_each_sched_entity(se) { @@ -4101,12 +4096,16 @@ static int wake_affine(struct sched_domain *sd, struct task_struct *p, int sync) */ static struct sched_group * find_idlest_group(struct sched_domain *sd, struct task_struct *p, - int this_cpu, int load_idx) + int this_cpu, int sd_flag) { struct sched_group *idlest = NULL, *group = sd->groups; unsigned long min_load = ULONG_MAX, this_load = 0; + int load_idx = sd->forkexec_idx; int imbalance = 100 + (sd->imbalance_pct-100)/2; + if (sd_flag & SD_BALANCE_WAKE) + load_idx = sd->wake_idx; + do { unsigned long load, avg_load; int local_group; @@ -4274,7 +4273,6 @@ select_task_rq_fair(struct task_struct *p, int prev_cpu, int sd_flag, int wake_f } while (sd) { - int load_idx = sd->forkexec_idx; struct sched_group *group; int weight; @@ -4283,10 +4281,7 @@ select_task_rq_fair(struct task_struct *p, int prev_cpu, int sd_flag, int wake_f continue; } - if (sd_flag & SD_BALANCE_WAKE) - load_idx = sd->wake_idx; - - group = find_idlest_group(sd, p, cpu, load_idx); + group = find_idlest_group(sd, p, cpu, sd_flag); if (!group) { sd = sd->child; continue; @@ -5512,7 +5507,6 @@ static inline void update_sg_lb_stats(struct lb_env *env, struct sched_group *group, int load_idx, int local_group, struct sg_lb_stats *sgs) { - unsigned long nr_running; unsigned long load; int i; @@ -5521,8 +5515,6 @@ static inline void update_sg_lb_stats(struct lb_env *env, for_each_cpu_and(i, sched_group_cpus(group), env->cpus) { struct rq *rq = cpu_rq(i); - nr_running = rq->nr_running; - /* Bias balancing toward cpus of our domain */ if (local_group) load = target_load(i, load_idx); @@ -5530,7 +5522,7 @@ static inline void update_sg_lb_stats(struct lb_env *env, load = source_load(i, load_idx); sgs->group_load += load; - sgs->sum_nr_running += nr_running; + sgs->sum_nr_running += rq->nr_running; #ifdef CONFIG_NUMA_BALANCING sgs->nr_numa_running += rq->nr_numa_running; sgs->nr_preferred_running += rq->nr_preferred_running; @@ -6521,7 +6513,7 @@ static struct { unsigned long next_balance; /* in jiffy units */ } nohz ____cacheline_aligned; -static inline int find_new_ilb(int call_cpu) +static inline int find_new_ilb(void) { int ilb = cpumask_first(nohz.idle_cpus_mask); @@ -6536,13 +6528,13 @@ static inline int find_new_ilb(int call_cpu) * nohz_load_balancer CPU (if there is one) otherwise fallback to any idle * CPU (if there is one). */ -static void nohz_balancer_kick(int cpu) +static void nohz_balancer_kick(void) { int ilb_cpu; nohz.next_balance++; - ilb_cpu = find_new_ilb(cpu); + ilb_cpu = find_new_ilb(); if (ilb_cpu >= nr_cpu_ids) return; @@ -6652,10 +6644,10 @@ void update_max_interval(void) * * Balancing parameters are set up in init_sched_domains. */ -static void rebalance_domains(int cpu, enum cpu_idle_type idle) +static void rebalance_domains(struct rq *rq, enum cpu_idle_type idle) { int continue_balancing = 1; - struct rq *rq = cpu_rq(cpu); + int cpu = rq->cpu; unsigned long interval; struct sched_domain *sd; /* Earliest time when we have to do rebalance again */ @@ -6752,9 +6744,9 @@ out: * In CONFIG_NO_HZ_COMMON case, the idle balance kickee will do the * rebalancing for all the cpus for whom scheduler ticks are stopped. */ -static void nohz_idle_balance(int this_cpu, enum cpu_idle_type idle) +static void nohz_idle_balance(struct rq *this_rq, enum cpu_idle_type idle) { - struct rq *this_rq = cpu_rq(this_cpu); + int this_cpu = this_rq->cpu; struct rq *rq; int balance_cpu; @@ -6781,7 +6773,7 @@ static void nohz_idle_balance(int this_cpu, enum cpu_idle_type idle) update_idle_cpu_load(rq); raw_spin_unlock_irq(&rq->lock); - rebalance_domains(balance_cpu, CPU_IDLE); + rebalance_domains(rq, CPU_IDLE); if (time_after(this_rq->next_balance, rq->next_balance)) this_rq->next_balance = rq->next_balance; @@ -6800,14 +6792,14 @@ end: * - For SD_ASYM_PACKING, if the lower numbered cpu's in the scheduler * domain span are idle. */ -static inline int nohz_kick_needed(struct rq *rq, int cpu) +static inline int nohz_kick_needed(struct rq *rq) { unsigned long now = jiffies; struct sched_domain *sd; struct sched_group_power *sgp; - int nr_busy; + int nr_busy, cpu = rq->cpu; - if (unlikely(idle_cpu(cpu))) + if (unlikely(rq->idle_balance)) return 0; /* @@ -6856,7 +6848,7 @@ need_kick: return 1; } #else -static void nohz_idle_balance(int this_cpu, enum cpu_idle_type idle) { } +static void nohz_idle_balance(struct rq *this_rq, enum cpu_idle_type idle) { } #endif /* @@ -6865,38 +6857,39 @@ static void nohz_idle_balance(int this_cpu, enum cpu_idle_type idle) { } */ static void run_rebalance_domains(struct softirq_action *h) { - int this_cpu = smp_processor_id(); - struct rq *this_rq = cpu_rq(this_cpu); + struct rq *this_rq = this_rq(); enum cpu_idle_type idle = this_rq->idle_balance ? CPU_IDLE : CPU_NOT_IDLE; - rebalance_domains(this_cpu, idle); + rebalance_domains(this_rq, idle); /* * If this cpu has a pending nohz_balance_kick, then do the * balancing on behalf of the other idle cpus whose ticks are * stopped. */ - nohz_idle_balance(this_cpu, idle); + nohz_idle_balance(this_rq, idle); } -static inline int on_null_domain(int cpu) +static inline int on_null_domain(struct rq *rq) { - return !rcu_dereference_sched(cpu_rq(cpu)->sd); + return !rcu_dereference_sched(rq->sd); } /* * Trigger the SCHED_SOFTIRQ if it is time to do periodic load balancing. */ -void trigger_load_balance(struct rq *rq, int cpu) +void trigger_load_balance(struct rq *rq) { /* Don't need to rebalance while attached to NULL domain */ - if (time_after_eq(jiffies, rq->next_balance) && - likely(!on_null_domain(cpu))) + if (unlikely(on_null_domain(rq))) + return; + + if (time_after_eq(jiffies, rq->next_balance)) raise_softirq(SCHED_SOFTIRQ); #ifdef CONFIG_NO_HZ_COMMON - if (nohz_kick_needed(rq, cpu) && likely(!on_null_domain(cpu))) - nohz_balancer_kick(cpu); + if (nohz_kick_needed(rq)) + nohz_balancer_kick(); #endif } diff --git a/kernel/sched/rt.c b/kernel/sched/rt.c index 1c4065575fa2..a2740b775b45 100644 --- a/kernel/sched/rt.c +++ b/kernel/sched/rt.c @@ -1738,7 +1738,7 @@ static void task_woken_rt(struct rq *rq, struct task_struct *p) !test_tsk_need_resched(rq->curr) && has_pushable_tasks(rq) && p->nr_cpus_allowed > 1 && - rt_task(rq->curr) && + (dl_task(rq->curr) || rt_task(rq->curr)) && (rq->curr->nr_cpus_allowed < 2 || rq->curr->prio <= p->prio)) push_rt_tasks(rq); diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h index 88c85b21d633..c2119fd20f8b 100644 --- a/kernel/sched/sched.h +++ b/kernel/sched/sched.h @@ -2,6 +2,7 @@ #include <linux/sched.h> #include <linux/sched/sysctl.h> #include <linux/sched/rt.h> +#include <linux/sched/deadline.h> #include <linux/mutex.h> #include <linux/spinlock.h> #include <linux/stop_machine.h> @@ -9,6 +10,7 @@ #include <linux/slab.h> #include "cpupri.h" +#include "cpudeadline.h" #include "cpuacct.h" struct rq; @@ -73,6 +75,13 @@ extern void update_cpu_load_active(struct rq *this_rq); #define NICE_0_SHIFT SCHED_LOAD_SHIFT /* + * Single value that decides SCHED_DEADLINE internal math precision. + * 10 -> just above 1us + * 9 -> just above 0.5us + */ +#define DL_SCALE (10) + +/* * These are the 'tuning knobs' of the scheduler: */ @@ -81,11 +90,19 @@ extern void update_cpu_load_active(struct rq *this_rq); */ #define RUNTIME_INF ((u64)~0ULL) +static inline int fair_policy(int policy) +{ + return policy == SCHED_NORMAL || policy == SCHED_BATCH; +} + static inline int rt_policy(int policy) { - if (policy == SCHED_FIFO || policy == SCHED_RR) - return 1; - return 0; + return policy == SCHED_FIFO || policy == SCHED_RR; +} + +static inline int dl_policy(int policy) +{ + return policy == SCHED_DEADLINE; } static inline int task_has_rt_policy(struct task_struct *p) @@ -93,6 +110,25 @@ static inline int task_has_rt_policy(struct task_struct *p) return rt_policy(p->policy); } +static inline int task_has_dl_policy(struct task_struct *p) +{ + return dl_policy(p->policy); +} + +static inline bool dl_time_before(u64 a, u64 b) +{ + return (s64)(a - b) < 0; +} + +/* + * Tells if entity @a should preempt entity @b. + */ +static inline bool +dl_entity_preempt(struct sched_dl_entity *a, struct sched_dl_entity *b) +{ + return dl_time_before(a->deadline, b->deadline); +} + /* * This is the priority-queue data structure of the RT scheduling class: */ @@ -108,6 +144,47 @@ struct rt_bandwidth { u64 rt_runtime; struct hrtimer rt_period_timer; }; +/* + * To keep the bandwidth of -deadline tasks and groups under control + * we need some place where: + * - store the maximum -deadline bandwidth of the system (the group); + * - cache the fraction of that bandwidth that is currently allocated. + * + * This is all done in the data structure below. It is similar to the + * one used for RT-throttling (rt_bandwidth), with the main difference + * that, since here we are only interested in admission control, we + * do not decrease any runtime while the group "executes", neither we + * need a timer to replenish it. + * + * With respect to SMP, the bandwidth is given on a per-CPU basis, + * meaning that: + * - dl_bw (< 100%) is the bandwidth of the system (group) on each CPU; + * - dl_total_bw array contains, in the i-eth element, the currently + * allocated bandwidth on the i-eth CPU. + * Moreover, groups consume bandwidth on each CPU, while tasks only + * consume bandwidth on the CPU they're running on. + * Finally, dl_total_bw_cpu is used to cache the index of dl_total_bw + * that will be shown the next time the proc or cgroup controls will + * be red. It on its turn can be changed by writing on its own + * control. + */ +struct dl_bandwidth { + raw_spinlock_t dl_runtime_lock; + u64 dl_runtime; + u64 dl_period; +}; + +static inline int dl_bandwidth_enabled(void) +{ + return sysctl_sched_rt_runtime >= 0; +} + +extern struct dl_bw *dl_bw_of(int i); + +struct dl_bw { + raw_spinlock_t lock; + u64 bw, total_bw; +}; extern struct mutex sched_domains_mutex; @@ -364,6 +441,42 @@ struct rt_rq { #endif }; +/* Deadline class' related fields in a runqueue */ +struct dl_rq { + /* runqueue is an rbtree, ordered by deadline */ + struct rb_root rb_root; + struct rb_node *rb_leftmost; + + unsigned long dl_nr_running; + +#ifdef CONFIG_SMP + /* + * Deadline values of the currently executing and the + * earliest ready task on this rq. Caching these facilitates + * the decision wether or not a ready but not running task + * should migrate somewhere else. + */ + struct { + u64 curr; + u64 next; + } earliest_dl; + + unsigned long dl_nr_migratory; + unsigned long dl_nr_total; + int overloaded; + + /* + * Tasks on this rq that can be pushed away. They are kept in + * an rb-tree, ordered by tasks' deadlines, with caching + * of the leftmost (earliest deadline) element. + */ + struct rb_root pushable_dl_tasks_root; + struct rb_node *pushable_dl_tasks_leftmost; +#else + struct dl_bw dl_bw; +#endif +}; + #ifdef CONFIG_SMP /* @@ -382,6 +495,15 @@ struct root_domain { cpumask_var_t online; /* + * The bit corresponding to a CPU gets set here if such CPU has more + * than one runnable -deadline task (as it is below for RT tasks). + */ + cpumask_var_t dlo_mask; + atomic_t dlo_count; + struct dl_bw dl_bw; + struct cpudl cpudl; + + /* * The "RT overload" flag: it gets set if a CPU has more than * one runnable RT task. */ @@ -432,6 +554,7 @@ struct rq { struct cfs_rq cfs; struct rt_rq rt; + struct dl_rq dl; #ifdef CONFIG_FAIR_GROUP_SCHED /* list of leaf cfs_rq on this cpu: */ @@ -827,8 +950,6 @@ static inline u64 global_rt_runtime(void) return (u64)sysctl_sched_rt_runtime * NSEC_PER_USEC; } - - static inline int task_current(struct rq *rq, struct task_struct *p) { return rq->curr == p; @@ -988,6 +1109,7 @@ static const u32 prio_to_wmult[40] = { #else #define ENQUEUE_WAKING 0 #endif +#define ENQUEUE_REPLENISH 8 #define DEQUEUE_SLEEP 1 @@ -1023,6 +1145,7 @@ struct sched_class { void (*set_curr_task) (struct rq *rq); void (*task_tick) (struct rq *rq, struct task_struct *p, int queued); void (*task_fork) (struct task_struct *p); + void (*task_dead) (struct task_struct *p); void (*switched_from) (struct rq *this_rq, struct task_struct *task); void (*switched_to) (struct rq *this_rq, struct task_struct *task); @@ -1042,6 +1165,7 @@ struct sched_class { for (class = sched_class_highest; class; class = class->next) extern const struct sched_class stop_sched_class; +extern const struct sched_class dl_sched_class; extern const struct sched_class rt_sched_class; extern const struct sched_class fair_sched_class; extern const struct sched_class idle_sched_class; @@ -1051,7 +1175,7 @@ extern const struct sched_class idle_sched_class; extern void update_group_power(struct sched_domain *sd, int cpu); -extern void trigger_load_balance(struct rq *rq, int cpu); +extern void trigger_load_balance(struct rq *rq); extern void idle_balance(int this_cpu, struct rq *this_rq); extern void idle_enter_fair(struct rq *this_rq); @@ -1068,8 +1192,11 @@ static inline void idle_balance(int cpu, struct rq *rq) extern void sysrq_sched_debug_show(void); extern void sched_init_granularity(void); extern void update_max_interval(void); + +extern void init_sched_dl_class(void); extern void init_sched_rt_class(void); extern void init_sched_fair_class(void); +extern void init_sched_dl_class(void); extern void resched_task(struct task_struct *p); extern void resched_cpu(int cpu); @@ -1077,6 +1204,12 @@ extern void resched_cpu(int cpu); extern struct rt_bandwidth def_rt_bandwidth; extern void init_rt_bandwidth(struct rt_bandwidth *rt_b, u64 period, u64 runtime); +extern struct dl_bandwidth def_dl_bandwidth; +extern void init_dl_bandwidth(struct dl_bandwidth *dl_b, u64 period, u64 runtime); +extern void init_dl_task_timer(struct sched_dl_entity *dl_se); + +unsigned long to_ratio(u64 period, u64 runtime); + extern void update_idle_cpu_load(struct rq *this_rq); extern void init_task_runnable_average(struct task_struct *p); @@ -1353,6 +1486,7 @@ extern void print_rt_stats(struct seq_file *m, int cpu); extern void init_cfs_rq(struct cfs_rq *cfs_rq); extern void init_rt_rq(struct rt_rq *rt_rq, struct rq *rq); +extern void init_dl_rq(struct dl_rq *dl_rq, struct rq *rq); extern void cfs_bandwidth_usage_inc(void); extern void cfs_bandwidth_usage_dec(void); diff --git a/kernel/sched/stop_task.c b/kernel/sched/stop_task.c index 47197de8abd9..fdb6bb0b3356 100644 --- a/kernel/sched/stop_task.c +++ b/kernel/sched/stop_task.c @@ -103,7 +103,7 @@ get_rr_interval_stop(struct rq *rq, struct task_struct *task) * Simple, special scheduling class for the per-CPU stop tasks: */ const struct sched_class stop_sched_class = { - .next = &rt_sched_class, + .next = &dl_sched_class, .enqueue_task = enqueue_task_stop, .dequeue_task = dequeue_task_stop, diff --git a/kernel/signal.c b/kernel/signal.c index 940b30ee9a30..52f881db1ca0 100644 --- a/kernel/signal.c +++ b/kernel/signal.c @@ -2047,8 +2047,8 @@ static bool do_signal_stop(int signr) if (task_set_jobctl_pending(current, signr | gstop)) sig->group_stop_count++; - for (t = next_thread(current); t != current; - t = next_thread(t)) { + t = current; + while_each_thread(current, t) { /* * Setting state to TASK_STOPPED for a group * stop is always done with the siglock held, @@ -3125,8 +3125,7 @@ int do_sigaction(int sig, struct k_sigaction *act, struct k_sigaction *oact) rm_from_queue_full(&mask, &t->signal->shared_pending); do { rm_from_queue_full(&mask, &t->pending); - t = next_thread(t); - } while (t != current); + } while_each_thread(current, t); } } diff --git a/kernel/softirq.c b/kernel/softirq.c index 11025ccc06dd..8a1e6e104892 100644 --- a/kernel/softirq.c +++ b/kernel/softirq.c @@ -89,7 +89,7 @@ static void wakeup_softirqd(void) * where hardirqs are disabled legitimately: */ #ifdef CONFIG_TRACE_IRQFLAGS -static void __local_bh_disable(unsigned long ip, unsigned int cnt) +void __local_bh_disable_ip(unsigned long ip, unsigned int cnt) { unsigned long flags; @@ -107,33 +107,21 @@ static void __local_bh_disable(unsigned long ip, unsigned int cnt) /* * Were softirqs turned off above: */ - if (softirq_count() == cnt) + if (softirq_count() == (cnt & SOFTIRQ_MASK)) trace_softirqs_off(ip); raw_local_irq_restore(flags); if (preempt_count() == cnt) trace_preempt_off(CALLER_ADDR0, get_parent_ip(CALLER_ADDR1)); } -#else /* !CONFIG_TRACE_IRQFLAGS */ -static inline void __local_bh_disable(unsigned long ip, unsigned int cnt) -{ - preempt_count_add(cnt); - barrier(); -} +EXPORT_SYMBOL(__local_bh_disable_ip); #endif /* CONFIG_TRACE_IRQFLAGS */ -void local_bh_disable(void) -{ - __local_bh_disable(_RET_IP_, SOFTIRQ_DISABLE_OFFSET); -} - -EXPORT_SYMBOL(local_bh_disable); - static void __local_bh_enable(unsigned int cnt) { WARN_ON_ONCE(!irqs_disabled()); - if (softirq_count() == cnt) + if (softirq_count() == (cnt & SOFTIRQ_MASK)) trace_softirqs_on(_RET_IP_); preempt_count_sub(cnt); } @@ -151,7 +139,7 @@ void _local_bh_enable(void) EXPORT_SYMBOL(_local_bh_enable); -static inline void _local_bh_enable_ip(unsigned long ip) +void __local_bh_enable_ip(unsigned long ip, unsigned int cnt) { WARN_ON_ONCE(in_irq() || irqs_disabled()); #ifdef CONFIG_TRACE_IRQFLAGS @@ -166,7 +154,7 @@ static inline void _local_bh_enable_ip(unsigned long ip) * Keep preemption disabled until we are done with * softirq processing: */ - preempt_count_sub(SOFTIRQ_DISABLE_OFFSET - 1); + preempt_count_sub(cnt - 1); if (unlikely(!in_interrupt() && local_softirq_pending())) { /* @@ -182,18 +170,7 @@ static inline void _local_bh_enable_ip(unsigned long ip) #endif preempt_check_resched(); } - -void local_bh_enable(void) -{ - _local_bh_enable_ip(_RET_IP_); -} -EXPORT_SYMBOL(local_bh_enable); - -void local_bh_enable_ip(unsigned long ip) -{ - _local_bh_enable_ip(ip); -} -EXPORT_SYMBOL(local_bh_enable_ip); +EXPORT_SYMBOL(__local_bh_enable_ip); /* * We restart softirq processing for at most MAX_SOFTIRQ_RESTART times, @@ -211,14 +188,48 @@ EXPORT_SYMBOL(local_bh_enable_ip); #define MAX_SOFTIRQ_TIME msecs_to_jiffies(2) #define MAX_SOFTIRQ_RESTART 10 +#ifdef CONFIG_TRACE_IRQFLAGS +/* + * When we run softirqs from irq_exit() and thus on the hardirq stack we need + * to keep the lockdep irq context tracking as tight as possible in order to + * not miss-qualify lock contexts and miss possible deadlocks. + */ + +static inline bool lockdep_softirq_start(void) +{ + bool in_hardirq = false; + + if (trace_hardirq_context(current)) { + in_hardirq = true; + trace_hardirq_exit(); + } + + lockdep_softirq_enter(); + + return in_hardirq; +} + +static inline void lockdep_softirq_end(bool in_hardirq) +{ + lockdep_softirq_exit(); + + if (in_hardirq) + trace_hardirq_enter(); +} +#else +static inline bool lockdep_softirq_start(void) { return false; } +static inline void lockdep_softirq_end(bool in_hardirq) { } +#endif + asmlinkage void __do_softirq(void) { - struct softirq_action *h; - __u32 pending; unsigned long end = jiffies + MAX_SOFTIRQ_TIME; - int cpu; unsigned long old_flags = current->flags; int max_restart = MAX_SOFTIRQ_RESTART; + struct softirq_action *h; + bool in_hardirq; + __u32 pending; + int cpu; /* * Mask out PF_MEMALLOC s current task context is borrowed for the @@ -230,8 +241,8 @@ asmlinkage void __do_softirq(void) pending = local_softirq_pending(); account_irq_enter_time(current); - __local_bh_disable(_RET_IP_, SOFTIRQ_OFFSET); - lockdep_softirq_enter(); + __local_bh_disable_ip(_RET_IP_, SOFTIRQ_OFFSET); + in_hardirq = lockdep_softirq_start(); cpu = smp_processor_id(); restart: @@ -278,16 +289,13 @@ restart: wakeup_softirqd(); } - lockdep_softirq_exit(); - + lockdep_softirq_end(in_hardirq); account_irq_exit_time(current); __local_bh_enable(SOFTIRQ_OFFSET); WARN_ON_ONCE(in_interrupt()); tsk_restore_flags(current, old_flags, PF_MEMALLOC); } - - asmlinkage void do_softirq(void) { __u32 pending; @@ -311,8 +319,6 @@ asmlinkage void do_softirq(void) */ void irq_enter(void) { - int cpu = smp_processor_id(); - rcu_irq_enter(); if (is_idle_task(current) && !in_interrupt()) { /* @@ -320,7 +326,7 @@ void irq_enter(void) * here, as softirq will be serviced on return from interrupt. */ local_bh_disable(); - tick_check_idle(cpu); + tick_check_idle(); _local_bh_enable(); } @@ -375,13 +381,13 @@ void irq_exit(void) #endif account_irq_exit_time(current); - trace_hardirq_exit(); preempt_count_sub(HARDIRQ_OFFSET); if (!in_interrupt() && local_softirq_pending()) invoke_softirq(); tick_irq_exit(); rcu_irq_exit(); + trace_hardirq_exit(); /* must be last! */ } /* diff --git a/kernel/sys.c b/kernel/sys.c index c72311324ea7..c0a58be780a4 100644 --- a/kernel/sys.c +++ b/kernel/sys.c @@ -895,8 +895,7 @@ SYSCALL_DEFINE1(times, struct tms __user *, tbuf) * only important on a multi-user system anyway, to make sure one user * can't send a signal to a process owned by another. -TYT, 12/12/91 * - * Auch. Had to add the 'did_exec' flag to conform completely to POSIX. - * LBT 04.03.94 + * !PF_FORKNOEXEC check to conform completely to POSIX. */ SYSCALL_DEFINE2(setpgid, pid_t, pid, pid_t, pgid) { @@ -932,7 +931,7 @@ SYSCALL_DEFINE2(setpgid, pid_t, pid, pid_t, pgid) if (task_session(p) != task_session(group_leader)) goto out; err = -EACCES; - if (p->did_exec) + if (!(p->flags & PF_FORKNOEXEC)) goto out; } else { err = -ESRCH; @@ -1572,8 +1571,7 @@ static void k_getrusage(struct task_struct *p, int who, struct rusage *r) t = p; do { accumulate_thread_rusage(t, r); - t = next_thread(t); - } while (t != p); + } while_each_thread(p, t); break; default: diff --git a/kernel/sysctl.c b/kernel/sysctl.c index 34a604726d0b..096db7452cbd 100644 --- a/kernel/sysctl.c +++ b/kernel/sysctl.c @@ -62,6 +62,7 @@ #include <linux/capability.h> #include <linux/binfmts.h> #include <linux/sched/sysctl.h> +#include <linux/kexec.h> #include <asm/uaccess.h> #include <asm/processor.h> @@ -95,8 +96,6 @@ #if defined(CONFIG_SYSCTL) /* External variables not in a header file. */ -extern int sysctl_overcommit_memory; -extern int sysctl_overcommit_ratio; extern int max_threads; extern int suid_dumpable; #ifdef CONFIG_COREDUMP @@ -385,19 +384,21 @@ static struct ctl_table kern_table[] = { .proc_handler = proc_dointvec, }, { - .procname = "numa_balancing_settle_count", - .data = &sysctl_numa_balancing_settle_count, - .maxlen = sizeof(unsigned int), - .mode = 0644, - .proc_handler = proc_dointvec, - }, - { .procname = "numa_balancing_migrate_deferred", .data = &sysctl_numa_balancing_migrate_deferred, .maxlen = sizeof(unsigned int), .mode = 0644, .proc_handler = proc_dointvec, }, + { + .procname = "numa_balancing", + .data = NULL, /* filled in by handler */ + .maxlen = sizeof(unsigned int), + .mode = 0644, + .proc_handler = sysctl_numa_balancing, + .extra1 = &zero, + .extra2 = &one, + }, #endif /* CONFIG_NUMA_BALANCING */ #endif /* CONFIG_SCHED_DEBUG */ { @@ -614,6 +615,18 @@ static struct ctl_table kern_table[] = { .proc_handler = proc_dointvec, }, #endif +#ifdef CONFIG_KEXEC + { + .procname = "kexec_load_disabled", + .data = &kexec_load_disabled, + .maxlen = sizeof(int), + .mode = 0644, + /* only handle a transition from default "0" to "1" */ + .proc_handler = proc_dointvec_minmax, + .extra1 = &one, + .extra2 = &one, + }, +#endif #ifdef CONFIG_MODULES { .procname = "modprobe", @@ -1128,7 +1141,14 @@ static struct ctl_table vm_table[] = { .data = &sysctl_overcommit_ratio, .maxlen = sizeof(sysctl_overcommit_ratio), .mode = 0644, - .proc_handler = proc_dointvec, + .proc_handler = overcommit_ratio_handler, + }, + { + .procname = "overcommit_kbytes", + .data = &sysctl_overcommit_kbytes, + .maxlen = sizeof(sysctl_overcommit_kbytes), + .mode = 0644, + .proc_handler = overcommit_kbytes_handler, }, { .procname = "page-cluster", diff --git a/kernel/time/sched_clock.c b/kernel/time/sched_clock.c index 68b799375981..0abb36464281 100644 --- a/kernel/time/sched_clock.c +++ b/kernel/time/sched_clock.c @@ -74,7 +74,7 @@ unsigned long long notrace sched_clock(void) return cd.epoch_ns; do { - seq = read_seqcount_begin(&cd.seq); + seq = raw_read_seqcount_begin(&cd.seq); epoch_cyc = cd.epoch_cyc; epoch_ns = cd.epoch_ns; } while (read_seqcount_retry(&cd.seq, seq)); @@ -99,10 +99,10 @@ static void notrace update_sched_clock(void) cd.mult, cd.shift); raw_local_irq_save(flags); - write_seqcount_begin(&cd.seq); + raw_write_seqcount_begin(&cd.seq); cd.epoch_ns = ns; cd.epoch_cyc = cyc; - write_seqcount_end(&cd.seq); + raw_write_seqcount_end(&cd.seq); raw_local_irq_restore(flags); } diff --git a/kernel/time/tick-broadcast.c b/kernel/time/tick-broadcast.c index 9532690daaa9..43780ab5e279 100644 --- a/kernel/time/tick-broadcast.c +++ b/kernel/time/tick-broadcast.c @@ -538,10 +538,10 @@ int tick_resume_broadcast_oneshot(struct clock_event_device *bc) * Called from irq_enter() when idle was interrupted to reenable the * per cpu device. */ -void tick_check_oneshot_broadcast(int cpu) +void tick_check_oneshot_broadcast_this_cpu(void) { - if (cpumask_test_cpu(cpu, tick_broadcast_oneshot_mask)) { - struct tick_device *td = &per_cpu(tick_cpu_device, cpu); + if (cpumask_test_cpu(smp_processor_id(), tick_broadcast_oneshot_mask)) { + struct tick_device *td = &__get_cpu_var(tick_cpu_device); /* * We might be in the middle of switching over from diff --git a/kernel/time/tick-common.c b/kernel/time/tick-common.c index 162b03ab0ad2..20b2fe37d105 100644 --- a/kernel/time/tick-common.c +++ b/kernel/time/tick-common.c @@ -85,6 +85,7 @@ static void tick_periodic(int cpu) do_timer(1); write_sequnlock(&jiffies_lock); + update_wall_time(); } update_process_times(user_mode(get_irq_regs())); diff --git a/kernel/time/tick-internal.h b/kernel/time/tick-internal.h index 18e71f7fbc2a..8329669b51ec 100644 --- a/kernel/time/tick-internal.h +++ b/kernel/time/tick-internal.h @@ -51,7 +51,7 @@ extern void tick_broadcast_switch_to_oneshot(void); extern void tick_shutdown_broadcast_oneshot(unsigned int *cpup); extern int tick_resume_broadcast_oneshot(struct clock_event_device *bc); extern int tick_broadcast_oneshot_active(void); -extern void tick_check_oneshot_broadcast(int cpu); +extern void tick_check_oneshot_broadcast_this_cpu(void); bool tick_broadcast_oneshot_available(void); # else /* BROADCAST */ static inline void tick_broadcast_setup_oneshot(struct clock_event_device *bc) @@ -62,7 +62,7 @@ static inline void tick_broadcast_oneshot_control(unsigned long reason) { } static inline void tick_broadcast_switch_to_oneshot(void) { } static inline void tick_shutdown_broadcast_oneshot(unsigned int *cpup) { } static inline int tick_broadcast_oneshot_active(void) { return 0; } -static inline void tick_check_oneshot_broadcast(int cpu) { } +static inline void tick_check_oneshot_broadcast_this_cpu(void) { } static inline bool tick_broadcast_oneshot_available(void) { return true; } # endif /* !BROADCAST */ @@ -155,3 +155,4 @@ static inline int tick_device_is_functional(struct clock_event_device *dev) #endif extern void do_timer(unsigned long ticks); +extern void update_wall_time(void); diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c index ea20f7d1ac2c..08cb0c3b8ccb 100644 --- a/kernel/time/tick-sched.c +++ b/kernel/time/tick-sched.c @@ -86,6 +86,7 @@ static void tick_do_update_jiffies64(ktime_t now) tick_next_period = ktime_add(last_jiffies_update, tick_period); } write_sequnlock(&jiffies_lock); + update_wall_time(); } /* @@ -177,7 +178,7 @@ static bool can_stop_full_tick(void) * TODO: kick full dynticks CPUs when * sched_clock_stable is set. */ - if (!sched_clock_stable) { + if (!sched_clock_stable()) { trace_tick_stop(0, "unstable sched clock\n"); /* * Don't allow the user to think they can get @@ -391,11 +392,9 @@ __setup("nohz=", setup_tick_nohz); */ static void tick_nohz_update_jiffies(ktime_t now) { - int cpu = smp_processor_id(); - struct tick_sched *ts = &per_cpu(tick_cpu_sched, cpu); unsigned long flags; - ts->idle_waketime = now; + __this_cpu_write(tick_cpu_sched.idle_waketime, now); local_irq_save(flags); tick_do_update_jiffies64(now); @@ -426,17 +425,15 @@ update_ts_time_stats(int cpu, struct tick_sched *ts, ktime_t now, u64 *last_upda } -static void tick_nohz_stop_idle(int cpu, ktime_t now) +static void tick_nohz_stop_idle(struct tick_sched *ts, ktime_t now) { - struct tick_sched *ts = &per_cpu(tick_cpu_sched, cpu); - - update_ts_time_stats(cpu, ts, now, NULL); + update_ts_time_stats(smp_processor_id(), ts, now, NULL); ts->idle_active = 0; sched_clock_idle_wakeup_event(0); } -static ktime_t tick_nohz_start_idle(int cpu, struct tick_sched *ts) +static ktime_t tick_nohz_start_idle(struct tick_sched *ts) { ktime_t now = ktime_get(); @@ -754,7 +751,7 @@ static void __tick_nohz_idle_enter(struct tick_sched *ts) ktime_t now, expires; int cpu = smp_processor_id(); - now = tick_nohz_start_idle(cpu, ts); + now = tick_nohz_start_idle(ts); if (can_stop_idle_tick(cpu, ts)) { int was_stopped = ts->tick_stopped; @@ -911,8 +908,7 @@ static void tick_nohz_account_idle_ticks(struct tick_sched *ts) */ void tick_nohz_idle_exit(void) { - int cpu = smp_processor_id(); - struct tick_sched *ts = &per_cpu(tick_cpu_sched, cpu); + struct tick_sched *ts = &__get_cpu_var(tick_cpu_sched); ktime_t now; local_irq_disable(); @@ -925,7 +921,7 @@ void tick_nohz_idle_exit(void) now = ktime_get(); if (ts->idle_active) - tick_nohz_stop_idle(cpu, now); + tick_nohz_stop_idle(ts, now); if (ts->tick_stopped) { tick_nohz_restart_sched_tick(ts, now); @@ -1009,12 +1005,10 @@ static void tick_nohz_switch_to_nohz(void) * timer and do not touch the other magic bits which need to be done * when idle is left. */ -static void tick_nohz_kick_tick(int cpu, ktime_t now) +static void tick_nohz_kick_tick(struct tick_sched *ts, ktime_t now) { #if 0 /* Switch back to 2.6.27 behaviour */ - - struct tick_sched *ts = &per_cpu(tick_cpu_sched, cpu); ktime_t delta; /* @@ -1029,36 +1023,36 @@ static void tick_nohz_kick_tick(int cpu, ktime_t now) #endif } -static inline void tick_check_nohz(int cpu) +static inline void tick_check_nohz_this_cpu(void) { - struct tick_sched *ts = &per_cpu(tick_cpu_sched, cpu); + struct tick_sched *ts = &__get_cpu_var(tick_cpu_sched); ktime_t now; if (!ts->idle_active && !ts->tick_stopped) return; now = ktime_get(); if (ts->idle_active) - tick_nohz_stop_idle(cpu, now); + tick_nohz_stop_idle(ts, now); if (ts->tick_stopped) { tick_nohz_update_jiffies(now); - tick_nohz_kick_tick(cpu, now); + tick_nohz_kick_tick(ts, now); } } #else static inline void tick_nohz_switch_to_nohz(void) { } -static inline void tick_check_nohz(int cpu) { } +static inline void tick_check_nohz_this_cpu(void) { } #endif /* CONFIG_NO_HZ_COMMON */ /* * Called from irq_enter to notify about the possible interruption of idle() */ -void tick_check_idle(int cpu) +void tick_check_idle(void) { - tick_check_oneshot_broadcast(cpu); - tick_check_nohz(cpu); + tick_check_oneshot_broadcast_this_cpu(); + tick_check_nohz_this_cpu(); } /* diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c index 87b4f00284c9..0aa4ce81bc16 100644 --- a/kernel/time/timekeeping.c +++ b/kernel/time/timekeeping.c @@ -77,7 +77,7 @@ static void tk_set_wall_to_mono(struct timekeeper *tk, struct timespec wtm) tk->wall_to_monotonic = wtm; set_normalized_timespec(&tmp, -wtm.tv_sec, -wtm.tv_nsec); tk->offs_real = timespec_to_ktime(tmp); - tk->offs_tai = ktime_sub(tk->offs_real, ktime_set(tk->tai_offset, 0)); + tk->offs_tai = ktime_add(tk->offs_real, ktime_set(tk->tai_offset, 0)); } static void tk_set_sleep_time(struct timekeeper *tk, struct timespec t) @@ -90,8 +90,9 @@ static void tk_set_sleep_time(struct timekeeper *tk, struct timespec t) } /** - * timekeeper_setup_internals - Set up internals to use clocksource clock. + * tk_setup_internals - Set up internals to use clocksource clock. * + * @tk: The target timekeeper to setup. * @clock: Pointer to clocksource. * * Calculates a fixed cycle/nsec interval for a given clocksource/adjustment @@ -595,7 +596,7 @@ s32 timekeeping_get_tai_offset(void) static void __timekeeping_set_tai_offset(struct timekeeper *tk, s32 tai_offset) { tk->tai_offset = tai_offset; - tk->offs_tai = ktime_sub(tk->offs_real, ktime_set(tai_offset, 0)); + tk->offs_tai = ktime_add(tk->offs_real, ktime_set(tai_offset, 0)); } /** @@ -610,6 +611,7 @@ void timekeeping_set_tai_offset(s32 tai_offset) raw_spin_lock_irqsave(&timekeeper_lock, flags); write_seqcount_begin(&timekeeper_seq); __timekeeping_set_tai_offset(tk, tai_offset); + timekeeping_update(tk, TK_MIRROR | TK_CLOCK_WAS_SET); write_seqcount_end(&timekeeper_seq); raw_spin_unlock_irqrestore(&timekeeper_lock, flags); clock_was_set(); @@ -1023,6 +1025,8 @@ static int timekeeping_suspend(void) timekeeping_suspend_time = timespec_add(timekeeping_suspend_time, delta_delta); } + + timekeeping_update(tk, TK_MIRROR); write_seqcount_end(&timekeeper_seq); raw_spin_unlock_irqrestore(&timekeeper_lock, flags); @@ -1130,16 +1134,6 @@ static void timekeeping_adjust(struct timekeeper *tk, s64 offset) * we can adjust by 1. */ error >>= 2; - /* - * XXX - In update_wall_time, we round up to the next - * nanosecond, and store the amount rounded up into - * the error. This causes the likely below to be unlikely. - * - * The proper fix is to avoid rounding up by using - * the high precision tk->xtime_nsec instead of - * xtime.tv_nsec everywhere. Fixing this will take some - * time. - */ if (likely(error <= interval)) adj = 1; else @@ -1255,7 +1249,7 @@ out_adjust: static inline unsigned int accumulate_nsecs_to_secs(struct timekeeper *tk) { u64 nsecps = (u64)NSEC_PER_SEC << tk->shift; - unsigned int action = 0; + unsigned int clock_set = 0; while (tk->xtime_nsec >= nsecps) { int leap; @@ -1277,11 +1271,10 @@ static inline unsigned int accumulate_nsecs_to_secs(struct timekeeper *tk) __timekeeping_set_tai_offset(tk, tk->tai_offset - leap); - clock_was_set_delayed(); - action = TK_CLOCK_WAS_SET; + clock_set = TK_CLOCK_WAS_SET; } } - return action; + return clock_set; } /** @@ -1294,7 +1287,8 @@ static inline unsigned int accumulate_nsecs_to_secs(struct timekeeper *tk) * Returns the unconsumed cycles. */ static cycle_t logarithmic_accumulation(struct timekeeper *tk, cycle_t offset, - u32 shift) + u32 shift, + unsigned int *clock_set) { cycle_t interval = tk->cycle_interval << shift; u64 raw_nsecs; @@ -1308,7 +1302,7 @@ static cycle_t logarithmic_accumulation(struct timekeeper *tk, cycle_t offset, tk->cycle_last += interval; tk->xtime_nsec += tk->xtime_interval << shift; - accumulate_nsecs_to_secs(tk); + *clock_set |= accumulate_nsecs_to_secs(tk); /* Accumulate raw time */ raw_nsecs = (u64)tk->raw_interval << shift; @@ -1359,14 +1353,14 @@ static inline void old_vsyscall_fixup(struct timekeeper *tk) * update_wall_time - Uses the current clocksource to increment the wall time * */ -static void update_wall_time(void) +void update_wall_time(void) { struct clocksource *clock; struct timekeeper *real_tk = &timekeeper; struct timekeeper *tk = &shadow_timekeeper; cycle_t offset; int shift = 0, maxshift; - unsigned int action; + unsigned int clock_set = 0; unsigned long flags; raw_spin_lock_irqsave(&timekeeper_lock, flags); @@ -1401,7 +1395,8 @@ static void update_wall_time(void) maxshift = (64 - (ilog2(ntp_tick_length())+1)) - 1; shift = min(shift, maxshift); while (offset >= tk->cycle_interval) { - offset = logarithmic_accumulation(tk, offset, shift); + offset = logarithmic_accumulation(tk, offset, shift, + &clock_set); if (offset < tk->cycle_interval<<shift) shift--; } @@ -1419,7 +1414,7 @@ static void update_wall_time(void) * Finally, make sure that after the rounding * xtime_nsec isn't larger than NSEC_PER_SEC */ - action = accumulate_nsecs_to_secs(tk); + clock_set |= accumulate_nsecs_to_secs(tk); write_seqcount_begin(&timekeeper_seq); /* Update clock->cycle_last with the new value */ @@ -1435,10 +1430,12 @@ static void update_wall_time(void) * updating. */ memcpy(real_tk, tk, sizeof(*tk)); - timekeeping_update(real_tk, action); + timekeeping_update(real_tk, clock_set); write_seqcount_end(&timekeeper_seq); out: raw_spin_unlock_irqrestore(&timekeeper_lock, flags); + if (clock_set) + clock_was_set(); } /** @@ -1583,7 +1580,6 @@ struct timespec get_monotonic_coarse(void) void do_timer(unsigned long ticks) { jiffies_64 += ticks; - update_wall_time(); calc_global_load(ticks); } @@ -1698,12 +1694,14 @@ int do_adjtimex(struct timex *txc) if (tai != orig_tai) { __timekeeping_set_tai_offset(tk, tai); - update_pvclock_gtod(tk, true); - clock_was_set_delayed(); + timekeeping_update(tk, TK_MIRROR | TK_CLOCK_WAS_SET); } write_seqcount_end(&timekeeper_seq); raw_spin_unlock_irqrestore(&timekeeper_lock, flags); + if (tai != orig_tai) + clock_was_set(); + ntp_notify_cmos_timer(); return ret; @@ -1739,4 +1737,5 @@ void xtime_update(unsigned long ticks) write_seqlock(&jiffies_lock); do_timer(ticks); write_sequnlock(&jiffies_lock); + update_wall_time(); } diff --git a/kernel/trace/Makefile b/kernel/trace/Makefile index d7e2068e4b71..1378e84fbe39 100644 --- a/kernel/trace/Makefile +++ b/kernel/trace/Makefile @@ -50,6 +50,7 @@ ifeq ($(CONFIG_PERF_EVENTS),y) obj-$(CONFIG_EVENT_TRACING) += trace_event_perf.o endif obj-$(CONFIG_EVENT_TRACING) += trace_events_filter.o +obj-$(CONFIG_EVENT_TRACING) += trace_events_trigger.o obj-$(CONFIG_KPROBE_EVENT) += trace_kprobe.o obj-$(CONFIG_TRACEPOINTS) += power-traces.o ifeq ($(CONFIG_PM_RUNTIME),y) diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index 72a0f81dc5a8..cd7f76d1eb86 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -85,6 +85,8 @@ int function_trace_stop __read_mostly; /* Current function tracing op */ struct ftrace_ops *function_trace_op __read_mostly = &ftrace_list_end; +/* What to set function_trace_op to */ +static struct ftrace_ops *set_function_trace_op; /* List for set_ftrace_pid's pids. */ LIST_HEAD(ftrace_pids); @@ -278,6 +280,29 @@ static void update_global_ops(void) global_ops.func = func; } +static void ftrace_sync(struct work_struct *work) +{ + /* + * This function is just a stub to implement a hard force + * of synchronize_sched(). This requires synchronizing + * tasks even in userspace and idle. + * + * Yes, function tracing is rude. + */ +} + +static void ftrace_sync_ipi(void *data) +{ + /* Probably not needed, but do it anyway */ + smp_rmb(); +} + +#ifdef CONFIG_FUNCTION_GRAPH_TRACER +static void update_function_graph_func(void); +#else +static inline void update_function_graph_func(void) { } +#endif + static void update_ftrace_function(void) { ftrace_func_t func; @@ -296,16 +321,61 @@ static void update_ftrace_function(void) !FTRACE_FORCE_LIST_FUNC)) { /* Set the ftrace_ops that the arch callback uses */ if (ftrace_ops_list == &global_ops) - function_trace_op = ftrace_global_list; + set_function_trace_op = ftrace_global_list; else - function_trace_op = ftrace_ops_list; + set_function_trace_op = ftrace_ops_list; func = ftrace_ops_list->func; } else { /* Just use the default ftrace_ops */ - function_trace_op = &ftrace_list_end; + set_function_trace_op = &ftrace_list_end; func = ftrace_ops_list_func; } + /* If there's no change, then do nothing more here */ + if (ftrace_trace_function == func) + return; + + update_function_graph_func(); + + /* + * If we are using the list function, it doesn't care + * about the function_trace_ops. + */ + if (func == ftrace_ops_list_func) { + ftrace_trace_function = func; + /* + * Don't even bother setting function_trace_ops, + * it would be racy to do so anyway. + */ + return; + } + +#ifndef CONFIG_DYNAMIC_FTRACE + /* + * For static tracing, we need to be a bit more careful. + * The function change takes affect immediately. Thus, + * we need to coorditate the setting of the function_trace_ops + * with the setting of the ftrace_trace_function. + * + * Set the function to the list ops, which will call the + * function we want, albeit indirectly, but it handles the + * ftrace_ops and doesn't depend on function_trace_op. + */ + ftrace_trace_function = ftrace_ops_list_func; + /* + * Make sure all CPUs see this. Yes this is slow, but static + * tracing is slow and nasty to have enabled. + */ + schedule_on_each_cpu(ftrace_sync); + /* Now all cpus are using the list ops. */ + function_trace_op = set_function_trace_op; + /* Make sure the function_trace_op is visible on all CPUs */ + smp_wmb(); + /* Nasty way to force a rmb on all cpus */ + smp_call_function(ftrace_sync_ipi, NULL, 1); + /* OK, we are all set to update the ftrace_trace_function now! */ +#endif /* !CONFIG_DYNAMIC_FTRACE */ + ftrace_trace_function = func; } @@ -410,17 +480,6 @@ static int __register_ftrace_function(struct ftrace_ops *ops) return 0; } -static void ftrace_sync(struct work_struct *work) -{ - /* - * This function is just a stub to implement a hard force - * of synchronize_sched(). This requires synchronizing - * tasks even in userspace and idle. - * - * Yes, function tracing is rude. - */ -} - static int __unregister_ftrace_function(struct ftrace_ops *ops) { int ret; @@ -439,20 +498,6 @@ static int __unregister_ftrace_function(struct ftrace_ops *ops) } else if (ops->flags & FTRACE_OPS_FL_CONTROL) { ret = remove_ftrace_list_ops(&ftrace_control_list, &control_ops, ops); - if (!ret) { - /* - * The ftrace_ops is now removed from the list, - * so there'll be no new users. We must ensure - * all current users are done before we free - * the control data. - * Note synchronize_sched() is not enough, as we - * use preempt_disable() to do RCU, but the function - * tracer can be called where RCU is not active - * (before user_exit()). - */ - schedule_on_each_cpu(ftrace_sync); - control_ops_free(ops); - } } else ret = remove_ftrace_ops(&ftrace_ops_list, ops); @@ -462,17 +507,6 @@ static int __unregister_ftrace_function(struct ftrace_ops *ops) if (ftrace_enabled) update_ftrace_function(); - /* - * Dynamic ops may be freed, we must make sure that all - * callers are done before leaving this function. - * - * Again, normal synchronize_sched() is not good enough. - * We need to do a hard force of sched synchronization. - */ - if (ops->flags & FTRACE_OPS_FL_DYNAMIC) - schedule_on_each_cpu(ftrace_sync); - - return 0; } @@ -1082,19 +1116,6 @@ static __init void ftrace_profile_debugfs(struct dentry *d_tracer) static struct pid * const ftrace_swapper_pid = &init_struct_pid; -loff_t -ftrace_filter_lseek(struct file *file, loff_t offset, int whence) -{ - loff_t ret; - - if (file->f_mode & FMODE_READ) - ret = seq_lseek(file, offset, whence); - else - file->f_pos = ret = 1; - - return ret; -} - #ifdef CONFIG_DYNAMIC_FTRACE #ifndef CONFIG_FTRACE_MCOUNT_RECORD @@ -1992,8 +2013,14 @@ void ftrace_modify_all_code(int command) else if (command & FTRACE_DISABLE_CALLS) ftrace_replace_code(0); - if (update && ftrace_trace_function != ftrace_ops_list_func) + if (update && ftrace_trace_function != ftrace_ops_list_func) { + function_trace_op = set_function_trace_op; + smp_wmb(); + /* If irqs are disabled, we are in stop machine */ + if (!irqs_disabled()) + smp_call_function(ftrace_sync_ipi, NULL, 1); ftrace_update_ftrace_func(ftrace_trace_function); + } if (command & FTRACE_START_FUNC_RET) ftrace_enable_ftrace_graph_caller(); @@ -2156,10 +2183,41 @@ static int ftrace_shutdown(struct ftrace_ops *ops, int command) command |= FTRACE_UPDATE_TRACE_FUNC; } - if (!command || !ftrace_enabled) + if (!command || !ftrace_enabled) { + /* + * If these are control ops, they still need their + * per_cpu field freed. Since, function tracing is + * not currently active, we can just free them + * without synchronizing all CPUs. + */ + if (ops->flags & FTRACE_OPS_FL_CONTROL) + control_ops_free(ops); return 0; + } ftrace_run_update_code(command); + + /* + * Dynamic ops may be freed, we must make sure that all + * callers are done before leaving this function. + * The same goes for freeing the per_cpu data of the control + * ops. + * + * Again, normal synchronize_sched() is not good enough. + * We need to do a hard force of sched synchronization. + * This is because we use preempt_disable() to do RCU, but + * the function tracers can be called where RCU is not watching + * (like before user_exit()). We can not rely on the RCU + * infrastructure to do the synchronization, thus we must do it + * ourselves. + */ + if (ops->flags & (FTRACE_OPS_FL_DYNAMIC | FTRACE_OPS_FL_CONTROL)) { + schedule_on_each_cpu(ftrace_sync); + + if (ops->flags & FTRACE_OPS_FL_CONTROL) + control_ops_free(ops); + } + return 0; } @@ -2739,7 +2797,7 @@ static void ftrace_filter_reset(struct ftrace_hash *hash) * routine, you can use ftrace_filter_write() for the write * routine if @flag has FTRACE_ITER_FILTER set, or * ftrace_notrace_write() if @flag has FTRACE_ITER_NOTRACE set. - * ftrace_filter_lseek() should be used as the lseek routine, and + * tracing_lseek() should be used as the lseek routine, and * release must call ftrace_regex_release(). */ int @@ -3767,7 +3825,7 @@ static const struct file_operations ftrace_filter_fops = { .open = ftrace_filter_open, .read = seq_read, .write = ftrace_filter_write, - .llseek = ftrace_filter_lseek, + .llseek = tracing_lseek, .release = ftrace_regex_release, }; @@ -3775,7 +3833,7 @@ static const struct file_operations ftrace_notrace_fops = { .open = ftrace_notrace_open, .read = seq_read, .write = ftrace_notrace_write, - .llseek = ftrace_filter_lseek, + .llseek = tracing_lseek, .release = ftrace_regex_release, }; @@ -4038,7 +4096,7 @@ static const struct file_operations ftrace_graph_fops = { .open = ftrace_graph_open, .read = seq_read, .write = ftrace_graph_write, - .llseek = ftrace_filter_lseek, + .llseek = tracing_lseek, .release = ftrace_graph_release, }; @@ -4046,7 +4104,7 @@ static const struct file_operations ftrace_graph_notrace_fops = { .open = ftrace_graph_notrace_open, .read = seq_read, .write = ftrace_graph_write, - .llseek = ftrace_filter_lseek, + .llseek = tracing_lseek, .release = ftrace_graph_release, }; #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ @@ -4719,7 +4777,7 @@ static const struct file_operations ftrace_pid_fops = { .open = ftrace_pid_open, .write = ftrace_pid_write, .read = seq_read, - .llseek = ftrace_filter_lseek, + .llseek = tracing_lseek, .release = ftrace_pid_release, }; @@ -4862,6 +4920,7 @@ int ftrace_graph_entry_stub(struct ftrace_graph_ent *trace) trace_func_graph_ret_t ftrace_graph_return = (trace_func_graph_ret_t)ftrace_stub; trace_func_graph_ent_t ftrace_graph_entry = ftrace_graph_entry_stub; +static trace_func_graph_ent_t __ftrace_graph_entry = ftrace_graph_entry_stub; /* Try to assign a return stack array on FTRACE_RETSTACK_ALLOC_SIZE tasks. */ static int alloc_retstack_tasklist(struct ftrace_ret_stack **ret_stack_list) @@ -5003,6 +5062,30 @@ static struct ftrace_ops fgraph_ops __read_mostly = { FTRACE_OPS_FL_RECURSION_SAFE, }; +static int ftrace_graph_entry_test(struct ftrace_graph_ent *trace) +{ + if (!ftrace_ops_test(&global_ops, trace->func, NULL)) + return 0; + return __ftrace_graph_entry(trace); +} + +/* + * The function graph tracer should only trace the functions defined + * by set_ftrace_filter and set_ftrace_notrace. If another function + * tracer ops is registered, the graph tracer requires testing the + * function against the global ops, and not just trace any function + * that any ftrace_ops registered. + */ +static void update_function_graph_func(void) +{ + if (ftrace_ops_list == &ftrace_list_end || + (ftrace_ops_list == &global_ops && + global_ops.next == &ftrace_list_end)) + ftrace_graph_entry = __ftrace_graph_entry; + else + ftrace_graph_entry = ftrace_graph_entry_test; +} + int register_ftrace_graph(trace_func_graph_ret_t retfunc, trace_func_graph_ent_t entryfunc) { @@ -5027,7 +5110,16 @@ int register_ftrace_graph(trace_func_graph_ret_t retfunc, } ftrace_graph_return = retfunc; - ftrace_graph_entry = entryfunc; + + /* + * Update the indirect function to the entryfunc, and the + * function that gets called to the entry_test first. Then + * call the update fgraph entry function to determine if + * the entryfunc should be called directly or not. + */ + __ftrace_graph_entry = entryfunc; + ftrace_graph_entry = ftrace_graph_entry_test; + update_function_graph_func(); ret = ftrace_startup(&fgraph_ops, FTRACE_START_FUNC_RET); @@ -5046,6 +5138,7 @@ void unregister_ftrace_graph(void) ftrace_graph_active--; ftrace_graph_return = (trace_func_graph_ret_t)ftrace_stub; ftrace_graph_entry = ftrace_graph_entry_stub; + __ftrace_graph_entry = ftrace_graph_entry_stub; ftrace_shutdown(&fgraph_ops, FTRACE_STOP_FUNC_RET); unregister_pm_notifier(&ftrace_suspend_notifier); unregister_trace_sched_switch(ftrace_graph_probe_sched_switch, NULL); diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c index cc2f66f68dc5..294b8a271a04 100644 --- a/kernel/trace/ring_buffer.c +++ b/kernel/trace/ring_buffer.c @@ -2558,7 +2558,7 @@ rb_reserve_next_event(struct ring_buffer *buffer, if (unlikely(test_time_stamp(delta))) { int local_clock_stable = 1; #ifdef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK - local_clock_stable = sched_clock_stable; + local_clock_stable = sched_clock_stable(); #endif WARN_ONCE(delta > (1ULL << 59), KERN_WARNING "Delta way too big! %llu ts=%llu write stamp = %llu\n%s", diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 9d20cd9743ef..20c755e018ca 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -595,6 +595,28 @@ void free_snapshot(struct trace_array *tr) } /** + * tracing_alloc_snapshot - allocate snapshot buffer. + * + * This only allocates the snapshot buffer if it isn't already + * allocated - it doesn't also take a snapshot. + * + * This is meant to be used in cases where the snapshot buffer needs + * to be set up for events that can't sleep but need to be able to + * trigger a snapshot. + */ +int tracing_alloc_snapshot(void) +{ + struct trace_array *tr = &global_trace; + int ret; + + ret = alloc_snapshot(tr); + WARN_ON(ret < 0); + + return ret; +} +EXPORT_SYMBOL_GPL(tracing_alloc_snapshot); + +/** * trace_snapshot_alloc - allocate and take a snapshot of the current buffer. * * This is similar to trace_snapshot(), but it will allocate the @@ -607,11 +629,10 @@ void free_snapshot(struct trace_array *tr) */ void tracing_snapshot_alloc(void) { - struct trace_array *tr = &global_trace; int ret; - ret = alloc_snapshot(tr); - if (WARN_ON(ret < 0)) + ret = tracing_alloc_snapshot(); + if (ret < 0) return; tracing_snapshot(); @@ -623,6 +644,12 @@ void tracing_snapshot(void) WARN_ONCE(1, "Snapshot feature not enabled, but internal snapshot used"); } EXPORT_SYMBOL_GPL(tracing_snapshot); +int tracing_alloc_snapshot(void) +{ + WARN_ONCE(1, "Snapshot feature not enabled, but snapshot allocation used"); + return -ENODEV; +} +EXPORT_SYMBOL_GPL(tracing_alloc_snapshot); void tracing_snapshot_alloc(void) { /* Give warning */ @@ -3156,19 +3183,23 @@ tracing_write_stub(struct file *filp, const char __user *ubuf, return count; } -static loff_t tracing_seek(struct file *file, loff_t offset, int origin) +loff_t tracing_lseek(struct file *file, loff_t offset, int whence) { + int ret; + if (file->f_mode & FMODE_READ) - return seq_lseek(file, offset, origin); + ret = seq_lseek(file, offset, whence); else - return 0; + file->f_pos = ret = 0; + + return ret; } static const struct file_operations tracing_fops = { .open = tracing_open, .read = seq_read, .write = tracing_write_stub, - .llseek = tracing_seek, + .llseek = tracing_lseek, .release = tracing_release, }; @@ -4212,12 +4243,6 @@ out: return sret; } -static void tracing_pipe_buf_release(struct pipe_inode_info *pipe, - struct pipe_buffer *buf) -{ - __free_page(buf->page); -} - static void tracing_spd_release_pipe(struct splice_pipe_desc *spd, unsigned int idx) { @@ -4229,7 +4254,7 @@ static const struct pipe_buf_operations tracing_pipe_buf_ops = { .map = generic_pipe_buf_map, .unmap = generic_pipe_buf_unmap, .confirm = generic_pipe_buf_confirm, - .release = tracing_pipe_buf_release, + .release = generic_pipe_buf_release, .steal = generic_pipe_buf_steal, .get = generic_pipe_buf_get, }; @@ -4913,7 +4938,7 @@ static const struct file_operations snapshot_fops = { .open = tracing_snapshot_open, .read = seq_read, .write = tracing_snapshot_write, - .llseek = tracing_seek, + .llseek = tracing_lseek, .release = tracing_snapshot_release, }; @@ -5883,6 +5908,8 @@ allocate_trace_buffer(struct trace_array *tr, struct trace_buffer *buf, int size rb_flags = trace_flags & TRACE_ITER_OVERWRITE ? RB_FL_OVERWRITE : 0; + buf->tr = tr; + buf->buffer = ring_buffer_alloc(size, rb_flags); if (!buf->buffer) return -ENOMEM; diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h index ea189e027b80..02b592f2d4b7 100644 --- a/kernel/trace/trace.h +++ b/kernel/trace/trace.h @@ -1,3 +1,4 @@ + #ifndef _LINUX_KERNEL_TRACE_H #define _LINUX_KERNEL_TRACE_H @@ -587,6 +588,8 @@ void tracing_start_sched_switch_record(void); int register_tracer(struct tracer *type); int is_tracing_stopped(void); +loff_t tracing_lseek(struct file *file, loff_t offset, int whence); + extern cpumask_var_t __read_mostly tracing_buffer_mask; #define for_each_tracing_cpu(cpu) \ @@ -1020,6 +1023,10 @@ extern int apply_subsystem_event_filter(struct ftrace_subsystem_dir *dir, extern void print_subsystem_event_filter(struct event_subsystem *system, struct trace_seq *s); extern int filter_assign_type(const char *type); +extern int create_event_filter(struct ftrace_event_call *call, + char *filter_str, bool set_str, + struct event_filter **filterp); +extern void free_event_filter(struct event_filter *filter); struct ftrace_event_field * trace_find_event_field(struct ftrace_event_call *call, char *name); @@ -1028,9 +1035,195 @@ extern void trace_event_enable_cmd_record(bool enable); extern int event_trace_add_tracer(struct dentry *parent, struct trace_array *tr); extern int event_trace_del_tracer(struct trace_array *tr); +extern struct ftrace_event_file *find_event_file(struct trace_array *tr, + const char *system, + const char *event); + +static inline void *event_file_data(struct file *filp) +{ + return ACCESS_ONCE(file_inode(filp)->i_private); +} + extern struct mutex event_mutex; extern struct list_head ftrace_events; +extern const struct file_operations event_trigger_fops; + +extern int register_trigger_cmds(void); +extern void clear_event_triggers(struct trace_array *tr); + +struct event_trigger_data { + unsigned long count; + int ref; + struct event_trigger_ops *ops; + struct event_command *cmd_ops; + struct event_filter __rcu *filter; + char *filter_str; + void *private_data; + struct list_head list; +}; + +/** + * struct event_trigger_ops - callbacks for trace event triggers + * + * The methods in this structure provide per-event trigger hooks for + * various trigger operations. + * + * All the methods below, except for @init() and @free(), must be + * implemented. + * + * @func: The trigger 'probe' function called when the triggering + * event occurs. The data passed into this callback is the data + * that was supplied to the event_command @reg() function that + * registered the trigger (see struct event_command). + * + * @init: An optional initialization function called for the trigger + * when the trigger is registered (via the event_command reg() + * function). This can be used to perform per-trigger + * initialization such as incrementing a per-trigger reference + * count, for instance. This is usually implemented by the + * generic utility function @event_trigger_init() (see + * trace_event_triggers.c). + * + * @free: An optional de-initialization function called for the + * trigger when the trigger is unregistered (via the + * event_command @reg() function). This can be used to perform + * per-trigger de-initialization such as decrementing a + * per-trigger reference count and freeing corresponding trigger + * data, for instance. This is usually implemented by the + * generic utility function @event_trigger_free() (see + * trace_event_triggers.c). + * + * @print: The callback function invoked to have the trigger print + * itself. This is usually implemented by a wrapper function + * that calls the generic utility function @event_trigger_print() + * (see trace_event_triggers.c). + */ +struct event_trigger_ops { + void (*func)(struct event_trigger_data *data); + int (*init)(struct event_trigger_ops *ops, + struct event_trigger_data *data); + void (*free)(struct event_trigger_ops *ops, + struct event_trigger_data *data); + int (*print)(struct seq_file *m, + struct event_trigger_ops *ops, + struct event_trigger_data *data); +}; + +/** + * struct event_command - callbacks and data members for event commands + * + * Event commands are invoked by users by writing the command name + * into the 'trigger' file associated with a trace event. The + * parameters associated with a specific invocation of an event + * command are used to create an event trigger instance, which is + * added to the list of trigger instances associated with that trace + * event. When the event is hit, the set of triggers associated with + * that event is invoked. + * + * The data members in this structure provide per-event command data + * for various event commands. + * + * All the data members below, except for @post_trigger, must be set + * for each event command. + * + * @name: The unique name that identifies the event command. This is + * the name used when setting triggers via trigger files. + * + * @trigger_type: A unique id that identifies the event command + * 'type'. This value has two purposes, the first to ensure that + * only one trigger of the same type can be set at a given time + * for a particular event e.g. it doesn't make sense to have both + * a traceon and traceoff trigger attached to a single event at + * the same time, so traceon and traceoff have the same type + * though they have different names. The @trigger_type value is + * also used as a bit value for deferring the actual trigger + * action until after the current event is finished. Some + * commands need to do this if they themselves log to the trace + * buffer (see the @post_trigger() member below). @trigger_type + * values are defined by adding new values to the trigger_type + * enum in include/linux/ftrace_event.h. + * + * @post_trigger: A flag that says whether or not this command needs + * to have its action delayed until after the current event has + * been closed. Some triggers need to avoid being invoked while + * an event is currently in the process of being logged, since + * the trigger may itself log data into the trace buffer. Thus + * we make sure the current event is committed before invoking + * those triggers. To do that, the trigger invocation is split + * in two - the first part checks the filter using the current + * trace record; if a command has the @post_trigger flag set, it + * sets a bit for itself in the return value, otherwise it + * directly invokes the trigger. Once all commands have been + * either invoked or set their return flag, the current record is + * either committed or discarded. At that point, if any commands + * have deferred their triggers, those commands are finally + * invoked following the close of the current event. In other + * words, if the event_trigger_ops @func() probe implementation + * itself logs to the trace buffer, this flag should be set, + * otherwise it can be left unspecified. + * + * All the methods below, except for @set_filter(), must be + * implemented. + * + * @func: The callback function responsible for parsing and + * registering the trigger written to the 'trigger' file by the + * user. It allocates the trigger instance and registers it with + * the appropriate trace event. It makes use of the other + * event_command callback functions to orchestrate this, and is + * usually implemented by the generic utility function + * @event_trigger_callback() (see trace_event_triggers.c). + * + * @reg: Adds the trigger to the list of triggers associated with the + * event, and enables the event trigger itself, after + * initializing it (via the event_trigger_ops @init() function). + * This is also where commands can use the @trigger_type value to + * make the decision as to whether or not multiple instances of + * the trigger should be allowed. This is usually implemented by + * the generic utility function @register_trigger() (see + * trace_event_triggers.c). + * + * @unreg: Removes the trigger from the list of triggers associated + * with the event, and disables the event trigger itself, after + * initializing it (via the event_trigger_ops @free() function). + * This is usually implemented by the generic utility function + * @unregister_trigger() (see trace_event_triggers.c). + * + * @set_filter: An optional function called to parse and set a filter + * for the trigger. If no @set_filter() method is set for the + * event command, filters set by the user for the command will be + * ignored. This is usually implemented by the generic utility + * function @set_trigger_filter() (see trace_event_triggers.c). + * + * @get_trigger_ops: The callback function invoked to retrieve the + * event_trigger_ops implementation associated with the command. + */ +struct event_command { + struct list_head list; + char *name; + enum event_trigger_type trigger_type; + bool post_trigger; + int (*func)(struct event_command *cmd_ops, + struct ftrace_event_file *file, + char *glob, char *cmd, char *params); + int (*reg)(char *glob, + struct event_trigger_ops *ops, + struct event_trigger_data *data, + struct ftrace_event_file *file); + void (*unreg)(char *glob, + struct event_trigger_ops *ops, + struct event_trigger_data *data, + struct ftrace_event_file *file); + int (*set_filter)(char *filter_str, + struct event_trigger_data *data, + struct ftrace_event_file *file); + struct event_trigger_ops *(*get_trigger_ops)(char *cmd, char *param); +}; + +extern int trace_event_enable_disable(struct ftrace_event_file *file, + int enable, int soft_disable); +extern int tracing_alloc_snapshot(void); + extern const char *__start___trace_bprintk_fmt[]; extern const char *__stop___trace_bprintk_fmt[]; diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c index a11800ae96de..e71ffd4eccb5 100644 --- a/kernel/trace/trace_events.c +++ b/kernel/trace/trace_events.c @@ -342,6 +342,12 @@ static int __ftrace_event_enable_disable(struct ftrace_event_file *file, return ret; } +int trace_event_enable_disable(struct ftrace_event_file *file, + int enable, int soft_disable) +{ + return __ftrace_event_enable_disable(file, enable, soft_disable); +} + static int ftrace_event_enable_disable(struct ftrace_event_file *file, int enable) { @@ -421,11 +427,6 @@ static void remove_subsystem(struct ftrace_subsystem_dir *dir) } } -static void *event_file_data(struct file *filp) -{ - return ACCESS_ONCE(file_inode(filp)->i_private); -} - static void remove_event_file_dir(struct ftrace_event_file *file) { struct dentry *dir = file->dir; @@ -1549,6 +1550,9 @@ event_create_dir(struct dentry *parent, struct ftrace_event_file *file) trace_create_file("filter", 0644, file->dir, file, &ftrace_event_filter_fops); + trace_create_file("trigger", 0644, file->dir, file, + &event_trigger_fops); + trace_create_file("format", 0444, file->dir, call, &ftrace_event_format_fops); @@ -1645,6 +1649,8 @@ trace_create_new_event(struct ftrace_event_call *call, file->event_call = call; file->tr = tr; atomic_set(&file->sm_ref, 0); + atomic_set(&file->tm_ref, 0); + INIT_LIST_HEAD(&file->triggers); list_add(&file->list, &tr->events); return file; @@ -1849,20 +1855,7 @@ __trace_add_event_dirs(struct trace_array *tr) } } -#ifdef CONFIG_DYNAMIC_FTRACE - -/* Avoid typos */ -#define ENABLE_EVENT_STR "enable_event" -#define DISABLE_EVENT_STR "disable_event" - -struct event_probe_data { - struct ftrace_event_file *file; - unsigned long count; - int ref; - bool enable; -}; - -static struct ftrace_event_file * +struct ftrace_event_file * find_event_file(struct trace_array *tr, const char *system, const char *event) { struct ftrace_event_file *file; @@ -1885,6 +1878,19 @@ find_event_file(struct trace_array *tr, const char *system, const char *event) return NULL; } +#ifdef CONFIG_DYNAMIC_FTRACE + +/* Avoid typos */ +#define ENABLE_EVENT_STR "enable_event" +#define DISABLE_EVENT_STR "disable_event" + +struct event_probe_data { + struct ftrace_event_file *file; + unsigned long count; + int ref; + bool enable; +}; + static void event_enable_probe(unsigned long ip, unsigned long parent_ip, void **_data) { @@ -2311,6 +2317,9 @@ int event_trace_del_tracer(struct trace_array *tr) { mutex_lock(&event_mutex); + /* Disable any event triggers and associated soft-disabled events */ + clear_event_triggers(tr); + /* Disable any running events */ __ftrace_set_clr_event_nolock(tr, NULL, NULL, NULL, 0); @@ -2377,6 +2386,8 @@ static __init int event_trace_enable(void) register_event_cmds(); + register_trigger_cmds(); + return 0; } diff --git a/kernel/trace/trace_events_filter.c b/kernel/trace/trace_events_filter.c index 2468f56dc5db..8a8631926a07 100644 --- a/kernel/trace/trace_events_filter.c +++ b/kernel/trace/trace_events_filter.c @@ -799,6 +799,11 @@ static void __free_filter(struct event_filter *filter) kfree(filter); } +void free_event_filter(struct event_filter *filter) +{ + __free_filter(filter); +} + void destroy_call_preds(struct ftrace_event_call *call) { __free_filter(call->filter); @@ -1938,6 +1943,13 @@ static int create_filter(struct ftrace_event_call *call, return err; } +int create_event_filter(struct ftrace_event_call *call, + char *filter_str, bool set_str, + struct event_filter **filterp) +{ + return create_filter(call, filter_str, set_str, filterp); +} + /** * create_system_filter - create a filter for an event_subsystem * @system: event_subsystem to create a filter for diff --git a/kernel/trace/trace_events_trigger.c b/kernel/trace/trace_events_trigger.c new file mode 100644 index 000000000000..8efbb69b04f0 --- /dev/null +++ b/kernel/trace/trace_events_trigger.c @@ -0,0 +1,1437 @@ +/* + * trace_events_trigger - trace event triggers + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. + * + * Copyright (C) 2013 Tom Zanussi <tom.zanussi@linux.intel.com> + */ + +#include <linux/module.h> +#include <linux/ctype.h> +#include <linux/mutex.h> +#include <linux/slab.h> + +#include "trace.h" + +static LIST_HEAD(trigger_commands); +static DEFINE_MUTEX(trigger_cmd_mutex); + +static void +trigger_data_free(struct event_trigger_data *data) +{ + if (data->cmd_ops->set_filter) + data->cmd_ops->set_filter(NULL, data, NULL); + + synchronize_sched(); /* make sure current triggers exit before free */ + kfree(data); +} + +/** + * event_triggers_call - Call triggers associated with a trace event + * @file: The ftrace_event_file associated with the event + * @rec: The trace entry for the event, NULL for unconditional invocation + * + * For each trigger associated with an event, invoke the trigger + * function registered with the associated trigger command. If rec is + * non-NULL, it means that the trigger requires further processing and + * shouldn't be unconditionally invoked. If rec is non-NULL and the + * trigger has a filter associated with it, rec will checked against + * the filter and if the record matches the trigger will be invoked. + * If the trigger is a 'post_trigger', meaning it shouldn't be invoked + * in any case until the current event is written, the trigger + * function isn't invoked but the bit associated with the deferred + * trigger is set in the return value. + * + * Returns an enum event_trigger_type value containing a set bit for + * any trigger that should be deferred, ETT_NONE if nothing to defer. + * + * Called from tracepoint handlers (with rcu_read_lock_sched() held). + * + * Return: an enum event_trigger_type value containing a set bit for + * any trigger that should be deferred, ETT_NONE if nothing to defer. + */ +enum event_trigger_type +event_triggers_call(struct ftrace_event_file *file, void *rec) +{ + struct event_trigger_data *data; + enum event_trigger_type tt = ETT_NONE; + struct event_filter *filter; + + if (list_empty(&file->triggers)) + return tt; + + list_for_each_entry_rcu(data, &file->triggers, list) { + if (!rec) { + data->ops->func(data); + continue; + } + filter = rcu_dereference(data->filter); + if (filter && !filter_match_preds(filter, rec)) + continue; + if (data->cmd_ops->post_trigger) { + tt |= data->cmd_ops->trigger_type; + continue; + } + data->ops->func(data); + } + return tt; +} +EXPORT_SYMBOL_GPL(event_triggers_call); + +/** + * event_triggers_post_call - Call 'post_triggers' for a trace event + * @file: The ftrace_event_file associated with the event + * @tt: enum event_trigger_type containing a set bit for each trigger to invoke + * + * For each trigger associated with an event, invoke the trigger + * function registered with the associated trigger command, if the + * corresponding bit is set in the tt enum passed into this function. + * See @event_triggers_call for details on how those bits are set. + * + * Called from tracepoint handlers (with rcu_read_lock_sched() held). + */ +void +event_triggers_post_call(struct ftrace_event_file *file, + enum event_trigger_type tt) +{ + struct event_trigger_data *data; + + list_for_each_entry_rcu(data, &file->triggers, list) { + if (data->cmd_ops->trigger_type & tt) + data->ops->func(data); + } +} +EXPORT_SYMBOL_GPL(event_triggers_post_call); + +#define SHOW_AVAILABLE_TRIGGERS (void *)(1UL) + +static void *trigger_next(struct seq_file *m, void *t, loff_t *pos) +{ + struct ftrace_event_file *event_file = event_file_data(m->private); + + if (t == SHOW_AVAILABLE_TRIGGERS) + return NULL; + + return seq_list_next(t, &event_file->triggers, pos); +} + +static void *trigger_start(struct seq_file *m, loff_t *pos) +{ + struct ftrace_event_file *event_file; + + /* ->stop() is called even if ->start() fails */ + mutex_lock(&event_mutex); + event_file = event_file_data(m->private); + if (unlikely(!event_file)) + return ERR_PTR(-ENODEV); + + if (list_empty(&event_file->triggers)) + return *pos == 0 ? SHOW_AVAILABLE_TRIGGERS : NULL; + + return seq_list_start(&event_file->triggers, *pos); +} + +static void trigger_stop(struct seq_file *m, void *t) +{ + mutex_unlock(&event_mutex); +} + +static int trigger_show(struct seq_file *m, void *v) +{ + struct event_trigger_data *data; + struct event_command *p; + + if (v == SHOW_AVAILABLE_TRIGGERS) { + seq_puts(m, "# Available triggers:\n"); + seq_putc(m, '#'); + mutex_lock(&trigger_cmd_mutex); + list_for_each_entry_reverse(p, &trigger_commands, list) + seq_printf(m, " %s", p->name); + seq_putc(m, '\n'); + mutex_unlock(&trigger_cmd_mutex); + return 0; + } + + data = list_entry(v, struct event_trigger_data, list); + data->ops->print(m, data->ops, data); + + return 0; +} + +static const struct seq_operations event_triggers_seq_ops = { + .start = trigger_start, + .next = trigger_next, + .stop = trigger_stop, + .show = trigger_show, +}; + +static int event_trigger_regex_open(struct inode *inode, struct file *file) +{ + int ret = 0; + + mutex_lock(&event_mutex); + + if (unlikely(!event_file_data(file))) { + mutex_unlock(&event_mutex); + return -ENODEV; + } + + if (file->f_mode & FMODE_READ) { + ret = seq_open(file, &event_triggers_seq_ops); + if (!ret) { + struct seq_file *m = file->private_data; + m->private = file; + } + } + + mutex_unlock(&event_mutex); + + return ret; +} + +static int trigger_process_regex(struct ftrace_event_file *file, char *buff) +{ + char *command, *next = buff; + struct event_command *p; + int ret = -EINVAL; + + command = strsep(&next, ": \t"); + command = (command[0] != '!') ? command : command + 1; + + mutex_lock(&trigger_cmd_mutex); + list_for_each_entry(p, &trigger_commands, list) { + if (strcmp(p->name, command) == 0) { + ret = p->func(p, file, buff, command, next); + goto out_unlock; + } + } + out_unlock: + mutex_unlock(&trigger_cmd_mutex); + + return ret; +} + +static ssize_t event_trigger_regex_write(struct file *file, + const char __user *ubuf, + size_t cnt, loff_t *ppos) +{ + struct ftrace_event_file *event_file; + ssize_t ret; + char *buf; + + if (!cnt) + return 0; + + if (cnt >= PAGE_SIZE) + return -EINVAL; + + buf = (char *)__get_free_page(GFP_TEMPORARY); + if (!buf) + return -ENOMEM; + + if (copy_from_user(buf, ubuf, cnt)) { + free_page((unsigned long)buf); + return -EFAULT; + } + buf[cnt] = '\0'; + strim(buf); + + mutex_lock(&event_mutex); + event_file = event_file_data(file); + if (unlikely(!event_file)) { + mutex_unlock(&event_mutex); + free_page((unsigned long)buf); + return -ENODEV; + } + ret = trigger_process_regex(event_file, buf); + mutex_unlock(&event_mutex); + + free_page((unsigned long)buf); + if (ret < 0) + goto out; + + *ppos += cnt; + ret = cnt; + out: + return ret; +} + +static int event_trigger_regex_release(struct inode *inode, struct file *file) +{ + mutex_lock(&event_mutex); + + if (file->f_mode & FMODE_READ) + seq_release(inode, file); + + mutex_unlock(&event_mutex); + + return 0; +} + +static ssize_t +event_trigger_write(struct file *filp, const char __user *ubuf, + size_t cnt, loff_t *ppos) +{ + return event_trigger_regex_write(filp, ubuf, cnt, ppos); +} + +static int +event_trigger_open(struct inode *inode, struct file *filp) +{ + return event_trigger_regex_open(inode, filp); +} + +static int +event_trigger_release(struct inode *inode, struct file *file) +{ + return event_trigger_regex_release(inode, file); +} + +const struct file_operations event_trigger_fops = { + .open = event_trigger_open, + .read = seq_read, + .write = event_trigger_write, + .llseek = tracing_lseek, + .release = event_trigger_release, +}; + +/* + * Currently we only register event commands from __init, so mark this + * __init too. + */ +static __init int register_event_command(struct event_command *cmd) +{ + struct event_command *p; + int ret = 0; + + mutex_lock(&trigger_cmd_mutex); + list_for_each_entry(p, &trigger_commands, list) { + if (strcmp(cmd->name, p->name) == 0) { + ret = -EBUSY; + goto out_unlock; + } + } + list_add(&cmd->list, &trigger_commands); + out_unlock: + mutex_unlock(&trigger_cmd_mutex); + + return ret; +} + +/* + * Currently we only unregister event commands from __init, so mark + * this __init too. + */ +static __init int unregister_event_command(struct event_command *cmd) +{ + struct event_command *p, *n; + int ret = -ENODEV; + + mutex_lock(&trigger_cmd_mutex); + list_for_each_entry_safe(p, n, &trigger_commands, list) { + if (strcmp(cmd->name, p->name) == 0) { + ret = 0; + list_del_init(&p->list); + goto out_unlock; + } + } + out_unlock: + mutex_unlock(&trigger_cmd_mutex); + + return ret; +} + +/** + * event_trigger_print - Generic event_trigger_ops @print implementation + * @name: The name of the event trigger + * @m: The seq_file being printed to + * @data: Trigger-specific data + * @filter_str: filter_str to print, if present + * + * Common implementation for event triggers to print themselves. + * + * Usually wrapped by a function that simply sets the @name of the + * trigger command and then invokes this. + * + * Return: 0 on success, errno otherwise + */ +static int +event_trigger_print(const char *name, struct seq_file *m, + void *data, char *filter_str) +{ + long count = (long)data; + + seq_printf(m, "%s", name); + + if (count == -1) + seq_puts(m, ":unlimited"); + else + seq_printf(m, ":count=%ld", count); + + if (filter_str) + seq_printf(m, " if %s\n", filter_str); + else + seq_puts(m, "\n"); + + return 0; +} + +/** + * event_trigger_init - Generic event_trigger_ops @init implementation + * @ops: The trigger ops associated with the trigger + * @data: Trigger-specific data + * + * Common implementation of event trigger initialization. + * + * Usually used directly as the @init method in event trigger + * implementations. + * + * Return: 0 on success, errno otherwise + */ +static int +event_trigger_init(struct event_trigger_ops *ops, + struct event_trigger_data *data) +{ + data->ref++; + return 0; +} + +/** + * event_trigger_free - Generic event_trigger_ops @free implementation + * @ops: The trigger ops associated with the trigger + * @data: Trigger-specific data + * + * Common implementation of event trigger de-initialization. + * + * Usually used directly as the @free method in event trigger + * implementations. + */ +static void +event_trigger_free(struct event_trigger_ops *ops, + struct event_trigger_data *data) +{ + if (WARN_ON_ONCE(data->ref <= 0)) + return; + + data->ref--; + if (!data->ref) + trigger_data_free(data); +} + +static int trace_event_trigger_enable_disable(struct ftrace_event_file *file, + int trigger_enable) +{ + int ret = 0; + + if (trigger_enable) { + if (atomic_inc_return(&file->tm_ref) > 1) + return ret; + set_bit(FTRACE_EVENT_FL_TRIGGER_MODE_BIT, &file->flags); + ret = trace_event_enable_disable(file, 1, 1); + } else { + if (atomic_dec_return(&file->tm_ref) > 0) + return ret; + clear_bit(FTRACE_EVENT_FL_TRIGGER_MODE_BIT, &file->flags); + ret = trace_event_enable_disable(file, 0, 1); + } + + return ret; +} + +/** + * clear_event_triggers - Clear all triggers associated with a trace array + * @tr: The trace array to clear + * + * For each trigger, the triggering event has its tm_ref decremented + * via trace_event_trigger_enable_disable(), and any associated event + * (in the case of enable/disable_event triggers) will have its sm_ref + * decremented via free()->trace_event_enable_disable(). That + * combination effectively reverses the soft-mode/trigger state added + * by trigger registration. + * + * Must be called with event_mutex held. + */ +void +clear_event_triggers(struct trace_array *tr) +{ + struct ftrace_event_file *file; + + list_for_each_entry(file, &tr->events, list) { + struct event_trigger_data *data; + list_for_each_entry_rcu(data, &file->triggers, list) { + trace_event_trigger_enable_disable(file, 0); + if (data->ops->free) + data->ops->free(data->ops, data); + } + } +} + +/** + * update_cond_flag - Set or reset the TRIGGER_COND bit + * @file: The ftrace_event_file associated with the event + * + * If an event has triggers and any of those triggers has a filter or + * a post_trigger, trigger invocation needs to be deferred until after + * the current event has logged its data, and the event should have + * its TRIGGER_COND bit set, otherwise the TRIGGER_COND bit should be + * cleared. + */ +static void update_cond_flag(struct ftrace_event_file *file) +{ + struct event_trigger_data *data; + bool set_cond = false; + + list_for_each_entry_rcu(data, &file->triggers, list) { + if (data->filter || data->cmd_ops->post_trigger) { + set_cond = true; + break; + } + } + + if (set_cond) + set_bit(FTRACE_EVENT_FL_TRIGGER_COND_BIT, &file->flags); + else + clear_bit(FTRACE_EVENT_FL_TRIGGER_COND_BIT, &file->flags); +} + +/** + * register_trigger - Generic event_command @reg implementation + * @glob: The raw string used to register the trigger + * @ops: The trigger ops associated with the trigger + * @data: Trigger-specific data to associate with the trigger + * @file: The ftrace_event_file associated with the event + * + * Common implementation for event trigger registration. + * + * Usually used directly as the @reg method in event command + * implementations. + * + * Return: 0 on success, errno otherwise + */ +static int register_trigger(char *glob, struct event_trigger_ops *ops, + struct event_trigger_data *data, + struct ftrace_event_file *file) +{ + struct event_trigger_data *test; + int ret = 0; + + list_for_each_entry_rcu(test, &file->triggers, list) { + if (test->cmd_ops->trigger_type == data->cmd_ops->trigger_type) { + ret = -EEXIST; + goto out; + } + } + + if (data->ops->init) { + ret = data->ops->init(data->ops, data); + if (ret < 0) + goto out; + } + + list_add_rcu(&data->list, &file->triggers); + ret++; + + if (trace_event_trigger_enable_disable(file, 1) < 0) { + list_del_rcu(&data->list); + ret--; + } + update_cond_flag(file); +out: + return ret; +} + +/** + * unregister_trigger - Generic event_command @unreg implementation + * @glob: The raw string used to register the trigger + * @ops: The trigger ops associated with the trigger + * @test: Trigger-specific data used to find the trigger to remove + * @file: The ftrace_event_file associated with the event + * + * Common implementation for event trigger unregistration. + * + * Usually used directly as the @unreg method in event command + * implementations. + */ +static void unregister_trigger(char *glob, struct event_trigger_ops *ops, + struct event_trigger_data *test, + struct ftrace_event_file *file) +{ + struct event_trigger_data *data; + bool unregistered = false; + + list_for_each_entry_rcu(data, &file->triggers, list) { + if (data->cmd_ops->trigger_type == test->cmd_ops->trigger_type) { + unregistered = true; + list_del_rcu(&data->list); + update_cond_flag(file); + trace_event_trigger_enable_disable(file, 0); + break; + } + } + + if (unregistered && data->ops->free) + data->ops->free(data->ops, data); +} + +/** + * event_trigger_callback - Generic event_command @func implementation + * @cmd_ops: The command ops, used for trigger registration + * @file: The ftrace_event_file associated with the event + * @glob: The raw string used to register the trigger + * @cmd: The cmd portion of the string used to register the trigger + * @param: The params portion of the string used to register the trigger + * + * Common implementation for event command parsing and trigger + * instantiation. + * + * Usually used directly as the @func method in event command + * implementations. + * + * Return: 0 on success, errno otherwise + */ +static int +event_trigger_callback(struct event_command *cmd_ops, + struct ftrace_event_file *file, + char *glob, char *cmd, char *param) +{ + struct event_trigger_data *trigger_data; + struct event_trigger_ops *trigger_ops; + char *trigger = NULL; + char *number; + int ret; + + /* separate the trigger from the filter (t:n [if filter]) */ + if (param && isdigit(param[0])) + trigger = strsep(¶m, " \t"); + + trigger_ops = cmd_ops->get_trigger_ops(cmd, trigger); + + ret = -ENOMEM; + trigger_data = kzalloc(sizeof(*trigger_data), GFP_KERNEL); + if (!trigger_data) + goto out; + + trigger_data->count = -1; + trigger_data->ops = trigger_ops; + trigger_data->cmd_ops = cmd_ops; + INIT_LIST_HEAD(&trigger_data->list); + + if (glob[0] == '!') { + cmd_ops->unreg(glob+1, trigger_ops, trigger_data, file); + kfree(trigger_data); + ret = 0; + goto out; + } + + if (trigger) { + number = strsep(&trigger, ":"); + + ret = -EINVAL; + if (!strlen(number)) + goto out_free; + + /* + * We use the callback data field (which is a pointer) + * as our counter. + */ + ret = kstrtoul(number, 0, &trigger_data->count); + if (ret) + goto out_free; + } + + if (!param) /* if param is non-empty, it's supposed to be a filter */ + goto out_reg; + + if (!cmd_ops->set_filter) + goto out_reg; + + ret = cmd_ops->set_filter(param, trigger_data, file); + if (ret < 0) + goto out_free; + + out_reg: + ret = cmd_ops->reg(glob, trigger_ops, trigger_data, file); + /* + * The above returns on success the # of functions enabled, + * but if it didn't find any functions it returns zero. + * Consider no functions a failure too. + */ + if (!ret) { + ret = -ENOENT; + goto out_free; + } else if (ret < 0) + goto out_free; + ret = 0; + out: + return ret; + + out_free: + if (cmd_ops->set_filter) + cmd_ops->set_filter(NULL, trigger_data, NULL); + kfree(trigger_data); + goto out; +} + +/** + * set_trigger_filter - Generic event_command @set_filter implementation + * @filter_str: The filter string for the trigger, NULL to remove filter + * @trigger_data: Trigger-specific data + * @file: The ftrace_event_file associated with the event + * + * Common implementation for event command filter parsing and filter + * instantiation. + * + * Usually used directly as the @set_filter method in event command + * implementations. + * + * Also used to remove a filter (if filter_str = NULL). + * + * Return: 0 on success, errno otherwise + */ +static int set_trigger_filter(char *filter_str, + struct event_trigger_data *trigger_data, + struct ftrace_event_file *file) +{ + struct event_trigger_data *data = trigger_data; + struct event_filter *filter = NULL, *tmp; + int ret = -EINVAL; + char *s; + + if (!filter_str) /* clear the current filter */ + goto assign; + + s = strsep(&filter_str, " \t"); + + if (!strlen(s) || strcmp(s, "if") != 0) + goto out; + + if (!filter_str) + goto out; + + /* The filter is for the 'trigger' event, not the triggered event */ + ret = create_event_filter(file->event_call, filter_str, false, &filter); + if (ret) + goto out; + assign: + tmp = rcu_access_pointer(data->filter); + + rcu_assign_pointer(data->filter, filter); + + if (tmp) { + /* Make sure the call is done with the filter */ + synchronize_sched(); + free_event_filter(tmp); + } + + kfree(data->filter_str); + data->filter_str = NULL; + + if (filter_str) { + data->filter_str = kstrdup(filter_str, GFP_KERNEL); + if (!data->filter_str) { + free_event_filter(rcu_access_pointer(data->filter)); + data->filter = NULL; + ret = -ENOMEM; + } + } + out: + return ret; +} + +static void +traceon_trigger(struct event_trigger_data *data) +{ + if (tracing_is_on()) + return; + + tracing_on(); +} + +static void +traceon_count_trigger(struct event_trigger_data *data) +{ + if (tracing_is_on()) + return; + + if (!data->count) + return; + + if (data->count != -1) + (data->count)--; + + tracing_on(); +} + +static void +traceoff_trigger(struct event_trigger_data *data) +{ + if (!tracing_is_on()) + return; + + tracing_off(); +} + +static void +traceoff_count_trigger(struct event_trigger_data *data) +{ + if (!tracing_is_on()) + return; + + if (!data->count) + return; + + if (data->count != -1) + (data->count)--; + + tracing_off(); +} + +static int +traceon_trigger_print(struct seq_file *m, struct event_trigger_ops *ops, + struct event_trigger_data *data) +{ + return event_trigger_print("traceon", m, (void *)data->count, + data->filter_str); +} + +static int +traceoff_trigger_print(struct seq_file *m, struct event_trigger_ops *ops, + struct event_trigger_data *data) +{ + return event_trigger_print("traceoff", m, (void *)data->count, + data->filter_str); +} + +static struct event_trigger_ops traceon_trigger_ops = { + .func = traceon_trigger, + .print = traceon_trigger_print, + .init = event_trigger_init, + .free = event_trigger_free, +}; + +static struct event_trigger_ops traceon_count_trigger_ops = { + .func = traceon_count_trigger, + .print = traceon_trigger_print, + .init = event_trigger_init, + .free = event_trigger_free, +}; + +static struct event_trigger_ops traceoff_trigger_ops = { + .func = traceoff_trigger, + .print = traceoff_trigger_print, + .init = event_trigger_init, + .free = event_trigger_free, +}; + +static struct event_trigger_ops traceoff_count_trigger_ops = { + .func = traceoff_count_trigger, + .print = traceoff_trigger_print, + .init = event_trigger_init, + .free = event_trigger_free, +}; + +static struct event_trigger_ops * +onoff_get_trigger_ops(char *cmd, char *param) +{ + struct event_trigger_ops *ops; + + /* we register both traceon and traceoff to this callback */ + if (strcmp(cmd, "traceon") == 0) + ops = param ? &traceon_count_trigger_ops : + &traceon_trigger_ops; + else + ops = param ? &traceoff_count_trigger_ops : + &traceoff_trigger_ops; + + return ops; +} + +static struct event_command trigger_traceon_cmd = { + .name = "traceon", + .trigger_type = ETT_TRACE_ONOFF, + .func = event_trigger_callback, + .reg = register_trigger, + .unreg = unregister_trigger, + .get_trigger_ops = onoff_get_trigger_ops, + .set_filter = set_trigger_filter, +}; + +static struct event_command trigger_traceoff_cmd = { + .name = "traceoff", + .trigger_type = ETT_TRACE_ONOFF, + .func = event_trigger_callback, + .reg = register_trigger, + .unreg = unregister_trigger, + .get_trigger_ops = onoff_get_trigger_ops, + .set_filter = set_trigger_filter, +}; + +#ifdef CONFIG_TRACER_SNAPSHOT +static void +snapshot_trigger(struct event_trigger_data *data) +{ + tracing_snapshot(); +} + +static void +snapshot_count_trigger(struct event_trigger_data *data) +{ + if (!data->count) + return; + + if (data->count != -1) + (data->count)--; + + snapshot_trigger(data); +} + +static int +register_snapshot_trigger(char *glob, struct event_trigger_ops *ops, + struct event_trigger_data *data, + struct ftrace_event_file *file) +{ + int ret = register_trigger(glob, ops, data, file); + + if (ret > 0 && tracing_alloc_snapshot() != 0) { + unregister_trigger(glob, ops, data, file); + ret = 0; + } + + return ret; +} + +static int +snapshot_trigger_print(struct seq_file *m, struct event_trigger_ops *ops, + struct event_trigger_data *data) +{ + return event_trigger_print("snapshot", m, (void *)data->count, + data->filter_str); +} + +static struct event_trigger_ops snapshot_trigger_ops = { + .func = snapshot_trigger, + .print = snapshot_trigger_print, + .init = event_trigger_init, + .free = event_trigger_free, +}; + +static struct event_trigger_ops snapshot_count_trigger_ops = { + .func = snapshot_count_trigger, + .print = snapshot_trigger_print, + .init = event_trigger_init, + .free = event_trigger_free, +}; + +static struct event_trigger_ops * +snapshot_get_trigger_ops(char *cmd, char *param) +{ + return param ? &snapshot_count_trigger_ops : &snapshot_trigger_ops; +} + +static struct event_command trigger_snapshot_cmd = { + .name = "snapshot", + .trigger_type = ETT_SNAPSHOT, + .func = event_trigger_callback, + .reg = register_snapshot_trigger, + .unreg = unregister_trigger, + .get_trigger_ops = snapshot_get_trigger_ops, + .set_filter = set_trigger_filter, +}; + +static __init int register_trigger_snapshot_cmd(void) +{ + int ret; + + ret = register_event_command(&trigger_snapshot_cmd); + WARN_ON(ret < 0); + + return ret; +} +#else +static __init int register_trigger_snapshot_cmd(void) { return 0; } +#endif /* CONFIG_TRACER_SNAPSHOT */ + +#ifdef CONFIG_STACKTRACE +/* + * Skip 3: + * stacktrace_trigger() + * event_triggers_post_call() + * ftrace_raw_event_xxx() + */ +#define STACK_SKIP 3 + +static void +stacktrace_trigger(struct event_trigger_data *data) +{ + trace_dump_stack(STACK_SKIP); +} + +static void +stacktrace_count_trigger(struct event_trigger_data *data) +{ + if (!data->count) + return; + + if (data->count != -1) + (data->count)--; + + stacktrace_trigger(data); +} + +static int +stacktrace_trigger_print(struct seq_file *m, struct event_trigger_ops *ops, + struct event_trigger_data *data) +{ + return event_trigger_print("stacktrace", m, (void *)data->count, + data->filter_str); +} + +static struct event_trigger_ops stacktrace_trigger_ops = { + .func = stacktrace_trigger, + .print = stacktrace_trigger_print, + .init = event_trigger_init, + .free = event_trigger_free, +}; + +static struct event_trigger_ops stacktrace_count_trigger_ops = { + .func = stacktrace_count_trigger, + .print = stacktrace_trigger_print, + .init = event_trigger_init, + .free = event_trigger_free, +}; + +static struct event_trigger_ops * +stacktrace_get_trigger_ops(char *cmd, char *param) +{ + return param ? &stacktrace_count_trigger_ops : &stacktrace_trigger_ops; +} + +static struct event_command trigger_stacktrace_cmd = { + .name = "stacktrace", + .trigger_type = ETT_STACKTRACE, + .post_trigger = true, + .func = event_trigger_callback, + .reg = register_trigger, + .unreg = unregister_trigger, + .get_trigger_ops = stacktrace_get_trigger_ops, + .set_filter = set_trigger_filter, +}; + +static __init int register_trigger_stacktrace_cmd(void) +{ + int ret; + + ret = register_event_command(&trigger_stacktrace_cmd); + WARN_ON(ret < 0); + + return ret; +} +#else +static __init int register_trigger_stacktrace_cmd(void) { return 0; } +#endif /* CONFIG_STACKTRACE */ + +static __init void unregister_trigger_traceon_traceoff_cmds(void) +{ + unregister_event_command(&trigger_traceon_cmd); + unregister_event_command(&trigger_traceoff_cmd); +} + +/* Avoid typos */ +#define ENABLE_EVENT_STR "enable_event" +#define DISABLE_EVENT_STR "disable_event" + +struct enable_trigger_data { + struct ftrace_event_file *file; + bool enable; +}; + +static void +event_enable_trigger(struct event_trigger_data *data) +{ + struct enable_trigger_data *enable_data = data->private_data; + + if (enable_data->enable) + clear_bit(FTRACE_EVENT_FL_SOFT_DISABLED_BIT, &enable_data->file->flags); + else + set_bit(FTRACE_EVENT_FL_SOFT_DISABLED_BIT, &enable_data->file->flags); +} + +static void +event_enable_count_trigger(struct event_trigger_data *data) +{ + struct enable_trigger_data *enable_data = data->private_data; + + if (!data->count) + return; + + /* Skip if the event is in a state we want to switch to */ + if (enable_data->enable == !(enable_data->file->flags & FTRACE_EVENT_FL_SOFT_DISABLED)) + return; + + if (data->count != -1) + (data->count)--; + + event_enable_trigger(data); +} + +static int +event_enable_trigger_print(struct seq_file *m, struct event_trigger_ops *ops, + struct event_trigger_data *data) +{ + struct enable_trigger_data *enable_data = data->private_data; + + seq_printf(m, "%s:%s:%s", + enable_data->enable ? ENABLE_EVENT_STR : DISABLE_EVENT_STR, + enable_data->file->event_call->class->system, + enable_data->file->event_call->name); + + if (data->count == -1) + seq_puts(m, ":unlimited"); + else + seq_printf(m, ":count=%ld", data->count); + + if (data->filter_str) + seq_printf(m, " if %s\n", data->filter_str); + else + seq_puts(m, "\n"); + + return 0; +} + +static void +event_enable_trigger_free(struct event_trigger_ops *ops, + struct event_trigger_data *data) +{ + struct enable_trigger_data *enable_data = data->private_data; + + if (WARN_ON_ONCE(data->ref <= 0)) + return; + + data->ref--; + if (!data->ref) { + /* Remove the SOFT_MODE flag */ + trace_event_enable_disable(enable_data->file, 0, 1); + module_put(enable_data->file->event_call->mod); + trigger_data_free(data); + kfree(enable_data); + } +} + +static struct event_trigger_ops event_enable_trigger_ops = { + .func = event_enable_trigger, + .print = event_enable_trigger_print, + .init = event_trigger_init, + .free = event_enable_trigger_free, +}; + +static struct event_trigger_ops event_enable_count_trigger_ops = { + .func = event_enable_count_trigger, + .print = event_enable_trigger_print, + .init = event_trigger_init, + .free = event_enable_trigger_free, +}; + +static struct event_trigger_ops event_disable_trigger_ops = { + .func = event_enable_trigger, + .print = event_enable_trigger_print, + .init = event_trigger_init, + .free = event_enable_trigger_free, +}; + +static struct event_trigger_ops event_disable_count_trigger_ops = { + .func = event_enable_count_trigger, + .print = event_enable_trigger_print, + .init = event_trigger_init, + .free = event_enable_trigger_free, +}; + +static int +event_enable_trigger_func(struct event_command *cmd_ops, + struct ftrace_event_file *file, + char *glob, char *cmd, char *param) +{ + struct ftrace_event_file *event_enable_file; + struct enable_trigger_data *enable_data; + struct event_trigger_data *trigger_data; + struct event_trigger_ops *trigger_ops; + struct trace_array *tr = file->tr; + const char *system; + const char *event; + char *trigger; + char *number; + bool enable; + int ret; + + if (!param) + return -EINVAL; + + /* separate the trigger from the filter (s:e:n [if filter]) */ + trigger = strsep(¶m, " \t"); + if (!trigger) + return -EINVAL; + + system = strsep(&trigger, ":"); + if (!trigger) + return -EINVAL; + + event = strsep(&trigger, ":"); + + ret = -EINVAL; + event_enable_file = find_event_file(tr, system, event); + if (!event_enable_file) + goto out; + + enable = strcmp(cmd, ENABLE_EVENT_STR) == 0; + + trigger_ops = cmd_ops->get_trigger_ops(cmd, trigger); + + ret = -ENOMEM; + trigger_data = kzalloc(sizeof(*trigger_data), GFP_KERNEL); + if (!trigger_data) + goto out; + + enable_data = kzalloc(sizeof(*enable_data), GFP_KERNEL); + if (!enable_data) { + kfree(trigger_data); + goto out; + } + + trigger_data->count = -1; + trigger_data->ops = trigger_ops; + trigger_data->cmd_ops = cmd_ops; + INIT_LIST_HEAD(&trigger_data->list); + RCU_INIT_POINTER(trigger_data->filter, NULL); + + enable_data->enable = enable; + enable_data->file = event_enable_file; + trigger_data->private_data = enable_data; + + if (glob[0] == '!') { + cmd_ops->unreg(glob+1, trigger_ops, trigger_data, file); + kfree(trigger_data); + kfree(enable_data); + ret = 0; + goto out; + } + + if (trigger) { + number = strsep(&trigger, ":"); + + ret = -EINVAL; + if (!strlen(number)) + goto out_free; + + /* + * We use the callback data field (which is a pointer) + * as our counter. + */ + ret = kstrtoul(number, 0, &trigger_data->count); + if (ret) + goto out_free; + } + + if (!param) /* if param is non-empty, it's supposed to be a filter */ + goto out_reg; + + if (!cmd_ops->set_filter) + goto out_reg; + + ret = cmd_ops->set_filter(param, trigger_data, file); + if (ret < 0) + goto out_free; + + out_reg: + /* Don't let event modules unload while probe registered */ + ret = try_module_get(event_enable_file->event_call->mod); + if (!ret) { + ret = -EBUSY; + goto out_free; + } + + ret = trace_event_enable_disable(event_enable_file, 1, 1); + if (ret < 0) + goto out_put; + ret = cmd_ops->reg(glob, trigger_ops, trigger_data, file); + /* + * The above returns on success the # of functions enabled, + * but if it didn't find any functions it returns zero. + * Consider no functions a failure too. + */ + if (!ret) { + ret = -ENOENT; + goto out_disable; + } else if (ret < 0) + goto out_disable; + /* Just return zero, not the number of enabled functions */ + ret = 0; + out: + return ret; + + out_disable: + trace_event_enable_disable(event_enable_file, 0, 1); + out_put: + module_put(event_enable_file->event_call->mod); + out_free: + if (cmd_ops->set_filter) + cmd_ops->set_filter(NULL, trigger_data, NULL); + kfree(trigger_data); + kfree(enable_data); + goto out; +} + +static int event_enable_register_trigger(char *glob, + struct event_trigger_ops *ops, + struct event_trigger_data *data, + struct ftrace_event_file *file) +{ + struct enable_trigger_data *enable_data = data->private_data; + struct enable_trigger_data *test_enable_data; + struct event_trigger_data *test; + int ret = 0; + + list_for_each_entry_rcu(test, &file->triggers, list) { + test_enable_data = test->private_data; + if (test_enable_data && + (test_enable_data->file == enable_data->file)) { + ret = -EEXIST; + goto out; + } + } + + if (data->ops->init) { + ret = data->ops->init(data->ops, data); + if (ret < 0) + goto out; + } + + list_add_rcu(&data->list, &file->triggers); + ret++; + + if (trace_event_trigger_enable_disable(file, 1) < 0) { + list_del_rcu(&data->list); + ret--; + } + update_cond_flag(file); +out: + return ret; +} + +static void event_enable_unregister_trigger(char *glob, + struct event_trigger_ops *ops, + struct event_trigger_data *test, + struct ftrace_event_file *file) +{ + struct enable_trigger_data *test_enable_data = test->private_data; + struct enable_trigger_data *enable_data; + struct event_trigger_data *data; + bool unregistered = false; + + list_for_each_entry_rcu(data, &file->triggers, list) { + enable_data = data->private_data; + if (enable_data && + (enable_data->file == test_enable_data->file)) { + unregistered = true; + list_del_rcu(&data->list); + update_cond_flag(file); + trace_event_trigger_enable_disable(file, 0); + break; + } + } + + if (unregistered && data->ops->free) + data->ops->free(data->ops, data); +} + +static struct event_trigger_ops * +event_enable_get_trigger_ops(char *cmd, char *param) +{ + struct event_trigger_ops *ops; + bool enable; + + enable = strcmp(cmd, ENABLE_EVENT_STR) == 0; + + if (enable) + ops = param ? &event_enable_count_trigger_ops : + &event_enable_trigger_ops; + else + ops = param ? &event_disable_count_trigger_ops : + &event_disable_trigger_ops; + + return ops; +} + +static struct event_command trigger_enable_cmd = { + .name = ENABLE_EVENT_STR, + .trigger_type = ETT_EVENT_ENABLE, + .func = event_enable_trigger_func, + .reg = event_enable_register_trigger, + .unreg = event_enable_unregister_trigger, + .get_trigger_ops = event_enable_get_trigger_ops, + .set_filter = set_trigger_filter, +}; + +static struct event_command trigger_disable_cmd = { + .name = DISABLE_EVENT_STR, + .trigger_type = ETT_EVENT_ENABLE, + .func = event_enable_trigger_func, + .reg = event_enable_register_trigger, + .unreg = event_enable_unregister_trigger, + .get_trigger_ops = event_enable_get_trigger_ops, + .set_filter = set_trigger_filter, +}; + +static __init void unregister_trigger_enable_disable_cmds(void) +{ + unregister_event_command(&trigger_enable_cmd); + unregister_event_command(&trigger_disable_cmd); +} + +static __init int register_trigger_enable_disable_cmds(void) +{ + int ret; + + ret = register_event_command(&trigger_enable_cmd); + if (WARN_ON(ret < 0)) + return ret; + ret = register_event_command(&trigger_disable_cmd); + if (WARN_ON(ret < 0)) + unregister_trigger_enable_disable_cmds(); + + return ret; +} + +static __init int register_trigger_traceon_traceoff_cmds(void) +{ + int ret; + + ret = register_event_command(&trigger_traceon_cmd); + if (WARN_ON(ret < 0)) + return ret; + ret = register_event_command(&trigger_traceoff_cmd); + if (WARN_ON(ret < 0)) + unregister_trigger_traceon_traceoff_cmds(); + + return ret; +} + +__init int register_trigger_cmds(void) +{ + register_trigger_traceon_traceoff_cmds(); + register_trigger_snapshot_cmd(); + register_trigger_stacktrace_cmd(); + register_trigger_enable_disable_cmds(); + + return 0; +} diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c index dae9541ada9e..bdbae450c13e 100644 --- a/kernel/trace/trace_kprobe.c +++ b/kernel/trace/trace_kprobe.c @@ -27,18 +27,12 @@ /** * Kprobe event core functions */ -struct trace_probe { +struct trace_kprobe { struct list_head list; struct kretprobe rp; /* Use rp.kp for kprobe use */ unsigned long nhit; - unsigned int flags; /* For TP_FLAG_* */ const char *symbol; /* symbol name */ - struct ftrace_event_class class; - struct ftrace_event_call call; - struct list_head files; - ssize_t size; /* trace entry size */ - unsigned int nr_args; - struct probe_arg args[]; + struct trace_probe tp; }; struct event_file_link { @@ -46,56 +40,46 @@ struct event_file_link { struct list_head list; }; -#define SIZEOF_TRACE_PROBE(n) \ - (offsetof(struct trace_probe, args) + \ +#define SIZEOF_TRACE_KPROBE(n) \ + (offsetof(struct trace_kprobe, tp.args) + \ (sizeof(struct probe_arg) * (n))) -static __kprobes bool trace_probe_is_return(struct trace_probe *tp) +static __kprobes bool trace_kprobe_is_return(struct trace_kprobe *tk) { - return tp->rp.handler != NULL; + return tk->rp.handler != NULL; } -static __kprobes const char *trace_probe_symbol(struct trace_probe *tp) +static __kprobes const char *trace_kprobe_symbol(struct trace_kprobe *tk) { - return tp->symbol ? tp->symbol : "unknown"; + return tk->symbol ? tk->symbol : "unknown"; } -static __kprobes unsigned long trace_probe_offset(struct trace_probe *tp) +static __kprobes unsigned long trace_kprobe_offset(struct trace_kprobe *tk) { - return tp->rp.kp.offset; + return tk->rp.kp.offset; } -static __kprobes bool trace_probe_is_enabled(struct trace_probe *tp) +static __kprobes bool trace_kprobe_has_gone(struct trace_kprobe *tk) { - return !!(tp->flags & (TP_FLAG_TRACE | TP_FLAG_PROFILE)); + return !!(kprobe_gone(&tk->rp.kp)); } -static __kprobes bool trace_probe_is_registered(struct trace_probe *tp) -{ - return !!(tp->flags & TP_FLAG_REGISTERED); -} - -static __kprobes bool trace_probe_has_gone(struct trace_probe *tp) -{ - return !!(kprobe_gone(&tp->rp.kp)); -} - -static __kprobes bool trace_probe_within_module(struct trace_probe *tp, - struct module *mod) +static __kprobes bool trace_kprobe_within_module(struct trace_kprobe *tk, + struct module *mod) { int len = strlen(mod->name); - const char *name = trace_probe_symbol(tp); + const char *name = trace_kprobe_symbol(tk); return strncmp(mod->name, name, len) == 0 && name[len] == ':'; } -static __kprobes bool trace_probe_is_on_module(struct trace_probe *tp) +static __kprobes bool trace_kprobe_is_on_module(struct trace_kprobe *tk) { - return !!strchr(trace_probe_symbol(tp), ':'); + return !!strchr(trace_kprobe_symbol(tk), ':'); } -static int register_probe_event(struct trace_probe *tp); -static int unregister_probe_event(struct trace_probe *tp); +static int register_kprobe_event(struct trace_kprobe *tk); +static int unregister_kprobe_event(struct trace_kprobe *tk); static DEFINE_MUTEX(probe_lock); static LIST_HEAD(probe_list); @@ -104,45 +88,224 @@ static int kprobe_dispatcher(struct kprobe *kp, struct pt_regs *regs); static int kretprobe_dispatcher(struct kretprobe_instance *ri, struct pt_regs *regs); +/* Memory fetching by symbol */ +struct symbol_cache { + char *symbol; + long offset; + unsigned long addr; +}; + +unsigned long update_symbol_cache(struct symbol_cache *sc) +{ + sc->addr = (unsigned long)kallsyms_lookup_name(sc->symbol); + + if (sc->addr) + sc->addr += sc->offset; + + return sc->addr; +} + +void free_symbol_cache(struct symbol_cache *sc) +{ + kfree(sc->symbol); + kfree(sc); +} + +struct symbol_cache *alloc_symbol_cache(const char *sym, long offset) +{ + struct symbol_cache *sc; + + if (!sym || strlen(sym) == 0) + return NULL; + + sc = kzalloc(sizeof(struct symbol_cache), GFP_KERNEL); + if (!sc) + return NULL; + + sc->symbol = kstrdup(sym, GFP_KERNEL); + if (!sc->symbol) { + kfree(sc); + return NULL; + } + sc->offset = offset; + update_symbol_cache(sc); + + return sc; +} + +/* + * Kprobes-specific fetch functions + */ +#define DEFINE_FETCH_stack(type) \ +static __kprobes void FETCH_FUNC_NAME(stack, type)(struct pt_regs *regs,\ + void *offset, void *dest) \ +{ \ + *(type *)dest = (type)regs_get_kernel_stack_nth(regs, \ + (unsigned int)((unsigned long)offset)); \ +} +DEFINE_BASIC_FETCH_FUNCS(stack) +/* No string on the stack entry */ +#define fetch_stack_string NULL +#define fetch_stack_string_size NULL + +#define DEFINE_FETCH_memory(type) \ +static __kprobes void FETCH_FUNC_NAME(memory, type)(struct pt_regs *regs,\ + void *addr, void *dest) \ +{ \ + type retval; \ + if (probe_kernel_address(addr, retval)) \ + *(type *)dest = 0; \ + else \ + *(type *)dest = retval; \ +} +DEFINE_BASIC_FETCH_FUNCS(memory) +/* + * Fetch a null-terminated string. Caller MUST set *(u32 *)dest with max + * length and relative data location. + */ +static __kprobes void FETCH_FUNC_NAME(memory, string)(struct pt_regs *regs, + void *addr, void *dest) +{ + long ret; + int maxlen = get_rloc_len(*(u32 *)dest); + u8 *dst = get_rloc_data(dest); + u8 *src = addr; + mm_segment_t old_fs = get_fs(); + + if (!maxlen) + return; + + /* + * Try to get string again, since the string can be changed while + * probing. + */ + set_fs(KERNEL_DS); + pagefault_disable(); + + do + ret = __copy_from_user_inatomic(dst++, src++, 1); + while (dst[-1] && ret == 0 && src - (u8 *)addr < maxlen); + + dst[-1] = '\0'; + pagefault_enable(); + set_fs(old_fs); + + if (ret < 0) { /* Failed to fetch string */ + ((u8 *)get_rloc_data(dest))[0] = '\0'; + *(u32 *)dest = make_data_rloc(0, get_rloc_offs(*(u32 *)dest)); + } else { + *(u32 *)dest = make_data_rloc(src - (u8 *)addr, + get_rloc_offs(*(u32 *)dest)); + } +} + +/* Return the length of string -- including null terminal byte */ +static __kprobes void FETCH_FUNC_NAME(memory, string_size)(struct pt_regs *regs, + void *addr, void *dest) +{ + mm_segment_t old_fs; + int ret, len = 0; + u8 c; + + old_fs = get_fs(); + set_fs(KERNEL_DS); + pagefault_disable(); + + do { + ret = __copy_from_user_inatomic(&c, (u8 *)addr + len, 1); + len++; + } while (c && ret == 0 && len < MAX_STRING_SIZE); + + pagefault_enable(); + set_fs(old_fs); + + if (ret < 0) /* Failed to check the length */ + *(u32 *)dest = 0; + else + *(u32 *)dest = len; +} + +#define DEFINE_FETCH_symbol(type) \ +__kprobes void FETCH_FUNC_NAME(symbol, type)(struct pt_regs *regs, \ + void *data, void *dest) \ +{ \ + struct symbol_cache *sc = data; \ + if (sc->addr) \ + fetch_memory_##type(regs, (void *)sc->addr, dest); \ + else \ + *(type *)dest = 0; \ +} +DEFINE_BASIC_FETCH_FUNCS(symbol) +DEFINE_FETCH_symbol(string) +DEFINE_FETCH_symbol(string_size) + +/* kprobes don't support file_offset fetch methods */ +#define fetch_file_offset_u8 NULL +#define fetch_file_offset_u16 NULL +#define fetch_file_offset_u32 NULL +#define fetch_file_offset_u64 NULL +#define fetch_file_offset_string NULL +#define fetch_file_offset_string_size NULL + +/* Fetch type information table */ +const struct fetch_type kprobes_fetch_type_table[] = { + /* Special types */ + [FETCH_TYPE_STRING] = __ASSIGN_FETCH_TYPE("string", string, string, + sizeof(u32), 1, "__data_loc char[]"), + [FETCH_TYPE_STRSIZE] = __ASSIGN_FETCH_TYPE("string_size", u32, + string_size, sizeof(u32), 0, "u32"), + /* Basic types */ + ASSIGN_FETCH_TYPE(u8, u8, 0), + ASSIGN_FETCH_TYPE(u16, u16, 0), + ASSIGN_FETCH_TYPE(u32, u32, 0), + ASSIGN_FETCH_TYPE(u64, u64, 0), + ASSIGN_FETCH_TYPE(s8, u8, 1), + ASSIGN_FETCH_TYPE(s16, u16, 1), + ASSIGN_FETCH_TYPE(s32, u32, 1), + ASSIGN_FETCH_TYPE(s64, u64, 1), + + ASSIGN_FETCH_TYPE_END +}; + /* * Allocate new trace_probe and initialize it (including kprobes). */ -static struct trace_probe *alloc_trace_probe(const char *group, +static struct trace_kprobe *alloc_trace_kprobe(const char *group, const char *event, void *addr, const char *symbol, unsigned long offs, int nargs, bool is_return) { - struct trace_probe *tp; + struct trace_kprobe *tk; int ret = -ENOMEM; - tp = kzalloc(SIZEOF_TRACE_PROBE(nargs), GFP_KERNEL); - if (!tp) + tk = kzalloc(SIZEOF_TRACE_KPROBE(nargs), GFP_KERNEL); + if (!tk) return ERR_PTR(ret); if (symbol) { - tp->symbol = kstrdup(symbol, GFP_KERNEL); - if (!tp->symbol) + tk->symbol = kstrdup(symbol, GFP_KERNEL); + if (!tk->symbol) goto error; - tp->rp.kp.symbol_name = tp->symbol; - tp->rp.kp.offset = offs; + tk->rp.kp.symbol_name = tk->symbol; + tk->rp.kp.offset = offs; } else - tp->rp.kp.addr = addr; + tk->rp.kp.addr = addr; if (is_return) - tp->rp.handler = kretprobe_dispatcher; + tk->rp.handler = kretprobe_dispatcher; else - tp->rp.kp.pre_handler = kprobe_dispatcher; + tk->rp.kp.pre_handler = kprobe_dispatcher; if (!event || !is_good_name(event)) { ret = -EINVAL; goto error; } - tp->call.class = &tp->class; - tp->call.name = kstrdup(event, GFP_KERNEL); - if (!tp->call.name) + tk->tp.call.class = &tk->tp.class; + tk->tp.call.name = kstrdup(event, GFP_KERNEL); + if (!tk->tp.call.name) goto error; if (!group || !is_good_name(group)) { @@ -150,42 +313,42 @@ static struct trace_probe *alloc_trace_probe(const char *group, goto error; } - tp->class.system = kstrdup(group, GFP_KERNEL); - if (!tp->class.system) + tk->tp.class.system = kstrdup(group, GFP_KERNEL); + if (!tk->tp.class.system) goto error; - INIT_LIST_HEAD(&tp->list); - INIT_LIST_HEAD(&tp->files); - return tp; + INIT_LIST_HEAD(&tk->list); + INIT_LIST_HEAD(&tk->tp.files); + return tk; error: - kfree(tp->call.name); - kfree(tp->symbol); - kfree(tp); + kfree(tk->tp.call.name); + kfree(tk->symbol); + kfree(tk); return ERR_PTR(ret); } -static void free_trace_probe(struct trace_probe *tp) +static void free_trace_kprobe(struct trace_kprobe *tk) { int i; - for (i = 0; i < tp->nr_args; i++) - traceprobe_free_probe_arg(&tp->args[i]); + for (i = 0; i < tk->tp.nr_args; i++) + traceprobe_free_probe_arg(&tk->tp.args[i]); - kfree(tp->call.class->system); - kfree(tp->call.name); - kfree(tp->symbol); - kfree(tp); + kfree(tk->tp.call.class->system); + kfree(tk->tp.call.name); + kfree(tk->symbol); + kfree(tk); } -static struct trace_probe *find_trace_probe(const char *event, - const char *group) +static struct trace_kprobe *find_trace_kprobe(const char *event, + const char *group) { - struct trace_probe *tp; + struct trace_kprobe *tk; - list_for_each_entry(tp, &probe_list, list) - if (strcmp(tp->call.name, event) == 0 && - strcmp(tp->call.class->system, group) == 0) - return tp; + list_for_each_entry(tk, &probe_list, list) + if (strcmp(tk->tp.call.name, event) == 0 && + strcmp(tk->tp.call.class->system, group) == 0) + return tk; return NULL; } @@ -194,7 +357,7 @@ static struct trace_probe *find_trace_probe(const char *event, * if the file is NULL, enable "perf" handler, or enable "trace" handler. */ static int -enable_trace_probe(struct trace_probe *tp, struct ftrace_event_file *file) +enable_trace_kprobe(struct trace_kprobe *tk, struct ftrace_event_file *file) { int ret = 0; @@ -208,17 +371,17 @@ enable_trace_probe(struct trace_probe *tp, struct ftrace_event_file *file) } link->file = file; - list_add_tail_rcu(&link->list, &tp->files); + list_add_tail_rcu(&link->list, &tk->tp.files); - tp->flags |= TP_FLAG_TRACE; + tk->tp.flags |= TP_FLAG_TRACE; } else - tp->flags |= TP_FLAG_PROFILE; + tk->tp.flags |= TP_FLAG_PROFILE; - if (trace_probe_is_registered(tp) && !trace_probe_has_gone(tp)) { - if (trace_probe_is_return(tp)) - ret = enable_kretprobe(&tp->rp); + if (trace_probe_is_registered(&tk->tp) && !trace_kprobe_has_gone(tk)) { + if (trace_kprobe_is_return(tk)) + ret = enable_kretprobe(&tk->rp); else - ret = enable_kprobe(&tp->rp.kp); + ret = enable_kprobe(&tk->rp.kp); } out: return ret; @@ -241,14 +404,14 @@ find_event_file_link(struct trace_probe *tp, struct ftrace_event_file *file) * if the file is NULL, disable "perf" handler, or disable "trace" handler. */ static int -disable_trace_probe(struct trace_probe *tp, struct ftrace_event_file *file) +disable_trace_kprobe(struct trace_kprobe *tk, struct ftrace_event_file *file) { struct event_file_link *link = NULL; int wait = 0; int ret = 0; if (file) { - link = find_event_file_link(tp, file); + link = find_event_file_link(&tk->tp, file); if (!link) { ret = -EINVAL; goto out; @@ -256,18 +419,18 @@ disable_trace_probe(struct trace_probe *tp, struct ftrace_event_file *file) list_del_rcu(&link->list); wait = 1; - if (!list_empty(&tp->files)) + if (!list_empty(&tk->tp.files)) goto out; - tp->flags &= ~TP_FLAG_TRACE; + tk->tp.flags &= ~TP_FLAG_TRACE; } else - tp->flags &= ~TP_FLAG_PROFILE; + tk->tp.flags &= ~TP_FLAG_PROFILE; - if (!trace_probe_is_enabled(tp) && trace_probe_is_registered(tp)) { - if (trace_probe_is_return(tp)) - disable_kretprobe(&tp->rp); + if (!trace_probe_is_enabled(&tk->tp) && trace_probe_is_registered(&tk->tp)) { + if (trace_kprobe_is_return(tk)) + disable_kretprobe(&tk->rp); else - disable_kprobe(&tp->rp.kp); + disable_kprobe(&tk->rp.kp); wait = 1; } out: @@ -288,40 +451,40 @@ disable_trace_probe(struct trace_probe *tp, struct ftrace_event_file *file) } /* Internal register function - just handle k*probes and flags */ -static int __register_trace_probe(struct trace_probe *tp) +static int __register_trace_kprobe(struct trace_kprobe *tk) { int i, ret; - if (trace_probe_is_registered(tp)) + if (trace_probe_is_registered(&tk->tp)) return -EINVAL; - for (i = 0; i < tp->nr_args; i++) - traceprobe_update_arg(&tp->args[i]); + for (i = 0; i < tk->tp.nr_args; i++) + traceprobe_update_arg(&tk->tp.args[i]); /* Set/clear disabled flag according to tp->flag */ - if (trace_probe_is_enabled(tp)) - tp->rp.kp.flags &= ~KPROBE_FLAG_DISABLED; + if (trace_probe_is_enabled(&tk->tp)) + tk->rp.kp.flags &= ~KPROBE_FLAG_DISABLED; else - tp->rp.kp.flags |= KPROBE_FLAG_DISABLED; + tk->rp.kp.flags |= KPROBE_FLAG_DISABLED; - if (trace_probe_is_return(tp)) - ret = register_kretprobe(&tp->rp); + if (trace_kprobe_is_return(tk)) + ret = register_kretprobe(&tk->rp); else - ret = register_kprobe(&tp->rp.kp); + ret = register_kprobe(&tk->rp.kp); if (ret == 0) - tp->flags |= TP_FLAG_REGISTERED; + tk->tp.flags |= TP_FLAG_REGISTERED; else { pr_warning("Could not insert probe at %s+%lu: %d\n", - trace_probe_symbol(tp), trace_probe_offset(tp), ret); - if (ret == -ENOENT && trace_probe_is_on_module(tp)) { + trace_kprobe_symbol(tk), trace_kprobe_offset(tk), ret); + if (ret == -ENOENT && trace_kprobe_is_on_module(tk)) { pr_warning("This probe might be able to register after" "target module is loaded. Continue.\n"); ret = 0; } else if (ret == -EILSEQ) { pr_warning("Probing address(0x%p) is not an " "instruction boundary.\n", - tp->rp.kp.addr); + tk->rp.kp.addr); ret = -EINVAL; } } @@ -330,67 +493,67 @@ static int __register_trace_probe(struct trace_probe *tp) } /* Internal unregister function - just handle k*probes and flags */ -static void __unregister_trace_probe(struct trace_probe *tp) +static void __unregister_trace_kprobe(struct trace_kprobe *tk) { - if (trace_probe_is_registered(tp)) { - if (trace_probe_is_return(tp)) - unregister_kretprobe(&tp->rp); + if (trace_probe_is_registered(&tk->tp)) { + if (trace_kprobe_is_return(tk)) + unregister_kretprobe(&tk->rp); else - unregister_kprobe(&tp->rp.kp); - tp->flags &= ~TP_FLAG_REGISTERED; + unregister_kprobe(&tk->rp.kp); + tk->tp.flags &= ~TP_FLAG_REGISTERED; /* Cleanup kprobe for reuse */ - if (tp->rp.kp.symbol_name) - tp->rp.kp.addr = NULL; + if (tk->rp.kp.symbol_name) + tk->rp.kp.addr = NULL; } } /* Unregister a trace_probe and probe_event: call with locking probe_lock */ -static int unregister_trace_probe(struct trace_probe *tp) +static int unregister_trace_kprobe(struct trace_kprobe *tk) { /* Enabled event can not be unregistered */ - if (trace_probe_is_enabled(tp)) + if (trace_probe_is_enabled(&tk->tp)) return -EBUSY; /* Will fail if probe is being used by ftrace or perf */ - if (unregister_probe_event(tp)) + if (unregister_kprobe_event(tk)) return -EBUSY; - __unregister_trace_probe(tp); - list_del(&tp->list); + __unregister_trace_kprobe(tk); + list_del(&tk->list); return 0; } /* Register a trace_probe and probe_event */ -static int register_trace_probe(struct trace_probe *tp) +static int register_trace_kprobe(struct trace_kprobe *tk) { - struct trace_probe *old_tp; + struct trace_kprobe *old_tk; int ret; mutex_lock(&probe_lock); /* Delete old (same name) event if exist */ - old_tp = find_trace_probe(tp->call.name, tp->call.class->system); - if (old_tp) { - ret = unregister_trace_probe(old_tp); + old_tk = find_trace_kprobe(tk->tp.call.name, tk->tp.call.class->system); + if (old_tk) { + ret = unregister_trace_kprobe(old_tk); if (ret < 0) goto end; - free_trace_probe(old_tp); + free_trace_kprobe(old_tk); } /* Register new event */ - ret = register_probe_event(tp); + ret = register_kprobe_event(tk); if (ret) { pr_warning("Failed to register probe event(%d)\n", ret); goto end; } /* Register k*probe */ - ret = __register_trace_probe(tp); + ret = __register_trace_kprobe(tk); if (ret < 0) - unregister_probe_event(tp); + unregister_kprobe_event(tk); else - list_add_tail(&tp->list, &probe_list); + list_add_tail(&tk->list, &probe_list); end: mutex_unlock(&probe_lock); @@ -398,11 +561,11 @@ end: } /* Module notifier call back, checking event on the module */ -static int trace_probe_module_callback(struct notifier_block *nb, +static int trace_kprobe_module_callback(struct notifier_block *nb, unsigned long val, void *data) { struct module *mod = data; - struct trace_probe *tp; + struct trace_kprobe *tk; int ret; if (val != MODULE_STATE_COMING) @@ -410,15 +573,15 @@ static int trace_probe_module_callback(struct notifier_block *nb, /* Update probes on coming module */ mutex_lock(&probe_lock); - list_for_each_entry(tp, &probe_list, list) { - if (trace_probe_within_module(tp, mod)) { + list_for_each_entry(tk, &probe_list, list) { + if (trace_kprobe_within_module(tk, mod)) { /* Don't need to check busy - this should have gone. */ - __unregister_trace_probe(tp); - ret = __register_trace_probe(tp); + __unregister_trace_kprobe(tk); + ret = __register_trace_kprobe(tk); if (ret) pr_warning("Failed to re-register probe %s on" "%s: %d\n", - tp->call.name, mod->name, ret); + tk->tp.call.name, mod->name, ret); } } mutex_unlock(&probe_lock); @@ -426,12 +589,12 @@ static int trace_probe_module_callback(struct notifier_block *nb, return NOTIFY_DONE; } -static struct notifier_block trace_probe_module_nb = { - .notifier_call = trace_probe_module_callback, +static struct notifier_block trace_kprobe_module_nb = { + .notifier_call = trace_kprobe_module_callback, .priority = 1 /* Invoked after kprobe module callback */ }; -static int create_trace_probe(int argc, char **argv) +static int create_trace_kprobe(int argc, char **argv) { /* * Argument syntax: @@ -451,7 +614,7 @@ static int create_trace_probe(int argc, char **argv) * Type of args: * FETCHARG:TYPE : use TYPE instead of unsigned long. */ - struct trace_probe *tp; + struct trace_kprobe *tk; int i, ret = 0; bool is_return = false, is_delete = false; char *symbol = NULL, *event = NULL, *group = NULL; @@ -498,16 +661,16 @@ static int create_trace_probe(int argc, char **argv) return -EINVAL; } mutex_lock(&probe_lock); - tp = find_trace_probe(event, group); - if (!tp) { + tk = find_trace_kprobe(event, group); + if (!tk) { mutex_unlock(&probe_lock); pr_info("Event %s/%s doesn't exist.\n", group, event); return -ENOENT; } /* delete an event */ - ret = unregister_trace_probe(tp); + ret = unregister_trace_kprobe(tk); if (ret == 0) - free_trace_probe(tp); + free_trace_kprobe(tk); mutex_unlock(&probe_lock); return ret; } @@ -554,47 +717,49 @@ static int create_trace_probe(int argc, char **argv) is_return ? 'r' : 'p', addr); event = buf; } - tp = alloc_trace_probe(group, event, addr, symbol, offset, argc, + tk = alloc_trace_kprobe(group, event, addr, symbol, offset, argc, is_return); - if (IS_ERR(tp)) { + if (IS_ERR(tk)) { pr_info("Failed to allocate trace_probe.(%d)\n", - (int)PTR_ERR(tp)); - return PTR_ERR(tp); + (int)PTR_ERR(tk)); + return PTR_ERR(tk); } /* parse arguments */ ret = 0; for (i = 0; i < argc && i < MAX_TRACE_ARGS; i++) { + struct probe_arg *parg = &tk->tp.args[i]; + /* Increment count for freeing args in error case */ - tp->nr_args++; + tk->tp.nr_args++; /* Parse argument name */ arg = strchr(argv[i], '='); if (arg) { *arg++ = '\0'; - tp->args[i].name = kstrdup(argv[i], GFP_KERNEL); + parg->name = kstrdup(argv[i], GFP_KERNEL); } else { arg = argv[i]; /* If argument name is omitted, set "argN" */ snprintf(buf, MAX_EVENT_NAME_LEN, "arg%d", i + 1); - tp->args[i].name = kstrdup(buf, GFP_KERNEL); + parg->name = kstrdup(buf, GFP_KERNEL); } - if (!tp->args[i].name) { + if (!parg->name) { pr_info("Failed to allocate argument[%d] name.\n", i); ret = -ENOMEM; goto error; } - if (!is_good_name(tp->args[i].name)) { + if (!is_good_name(parg->name)) { pr_info("Invalid argument[%d] name: %s\n", - i, tp->args[i].name); + i, parg->name); ret = -EINVAL; goto error; } - if (traceprobe_conflict_field_name(tp->args[i].name, - tp->args, i)) { + if (traceprobe_conflict_field_name(parg->name, + tk->tp.args, i)) { pr_info("Argument[%d] name '%s' conflicts with " "another field.\n", i, argv[i]); ret = -EINVAL; @@ -602,7 +767,7 @@ static int create_trace_probe(int argc, char **argv) } /* Parse fetch argument */ - ret = traceprobe_parse_probe_arg(arg, &tp->size, &tp->args[i], + ret = traceprobe_parse_probe_arg(arg, &tk->tp.size, parg, is_return, true); if (ret) { pr_info("Parse error at argument[%d]. (%d)\n", i, ret); @@ -610,35 +775,35 @@ static int create_trace_probe(int argc, char **argv) } } - ret = register_trace_probe(tp); + ret = register_trace_kprobe(tk); if (ret) goto error; return 0; error: - free_trace_probe(tp); + free_trace_kprobe(tk); return ret; } -static int release_all_trace_probes(void) +static int release_all_trace_kprobes(void) { - struct trace_probe *tp; + struct trace_kprobe *tk; int ret = 0; mutex_lock(&probe_lock); /* Ensure no probe is in use. */ - list_for_each_entry(tp, &probe_list, list) - if (trace_probe_is_enabled(tp)) { + list_for_each_entry(tk, &probe_list, list) + if (trace_probe_is_enabled(&tk->tp)) { ret = -EBUSY; goto end; } /* TODO: Use batch unregistration */ while (!list_empty(&probe_list)) { - tp = list_entry(probe_list.next, struct trace_probe, list); - ret = unregister_trace_probe(tp); + tk = list_entry(probe_list.next, struct trace_kprobe, list); + ret = unregister_trace_kprobe(tk); if (ret) goto end; - free_trace_probe(tp); + free_trace_kprobe(tk); } end: @@ -666,22 +831,22 @@ static void probes_seq_stop(struct seq_file *m, void *v) static int probes_seq_show(struct seq_file *m, void *v) { - struct trace_probe *tp = v; + struct trace_kprobe *tk = v; int i; - seq_printf(m, "%c", trace_probe_is_return(tp) ? 'r' : 'p'); - seq_printf(m, ":%s/%s", tp->call.class->system, tp->call.name); + seq_printf(m, "%c", trace_kprobe_is_return(tk) ? 'r' : 'p'); + seq_printf(m, ":%s/%s", tk->tp.call.class->system, tk->tp.call.name); - if (!tp->symbol) - seq_printf(m, " 0x%p", tp->rp.kp.addr); - else if (tp->rp.kp.offset) - seq_printf(m, " %s+%u", trace_probe_symbol(tp), - tp->rp.kp.offset); + if (!tk->symbol) + seq_printf(m, " 0x%p", tk->rp.kp.addr); + else if (tk->rp.kp.offset) + seq_printf(m, " %s+%u", trace_kprobe_symbol(tk), + tk->rp.kp.offset); else - seq_printf(m, " %s", trace_probe_symbol(tp)); + seq_printf(m, " %s", trace_kprobe_symbol(tk)); - for (i = 0; i < tp->nr_args; i++) - seq_printf(m, " %s=%s", tp->args[i].name, tp->args[i].comm); + for (i = 0; i < tk->tp.nr_args; i++) + seq_printf(m, " %s=%s", tk->tp.args[i].name, tk->tp.args[i].comm); seq_printf(m, "\n"); return 0; @@ -699,7 +864,7 @@ static int probes_open(struct inode *inode, struct file *file) int ret; if ((file->f_mode & FMODE_WRITE) && (file->f_flags & O_TRUNC)) { - ret = release_all_trace_probes(); + ret = release_all_trace_kprobes(); if (ret < 0) return ret; } @@ -711,7 +876,7 @@ static ssize_t probes_write(struct file *file, const char __user *buffer, size_t count, loff_t *ppos) { return traceprobe_probes_write(file, buffer, count, ppos, - create_trace_probe); + create_trace_kprobe); } static const struct file_operations kprobe_events_ops = { @@ -726,10 +891,10 @@ static const struct file_operations kprobe_events_ops = { /* Probes profiling interfaces */ static int probes_profile_seq_show(struct seq_file *m, void *v) { - struct trace_probe *tp = v; + struct trace_kprobe *tk = v; - seq_printf(m, " %-44s %15lu %15lu\n", tp->call.name, tp->nhit, - tp->rp.kp.nmissed); + seq_printf(m, " %-44s %15lu %15lu\n", tk->tp.call.name, tk->nhit, + tk->rp.kp.nmissed); return 0; } @@ -754,57 +919,9 @@ static const struct file_operations kprobe_profile_ops = { .release = seq_release, }; -/* Sum up total data length for dynamic arraies (strings) */ -static __kprobes int __get_data_size(struct trace_probe *tp, - struct pt_regs *regs) -{ - int i, ret = 0; - u32 len; - - for (i = 0; i < tp->nr_args; i++) - if (unlikely(tp->args[i].fetch_size.fn)) { - call_fetch(&tp->args[i].fetch_size, regs, &len); - ret += len; - } - - return ret; -} - -/* Store the value of each argument */ -static __kprobes void store_trace_args(int ent_size, struct trace_probe *tp, - struct pt_regs *regs, - u8 *data, int maxlen) -{ - int i; - u32 end = tp->size; - u32 *dl; /* Data (relative) location */ - - for (i = 0; i < tp->nr_args; i++) { - if (unlikely(tp->args[i].fetch_size.fn)) { - /* - * First, we set the relative location and - * maximum data length to *dl - */ - dl = (u32 *)(data + tp->args[i].offset); - *dl = make_data_rloc(maxlen, end - tp->args[i].offset); - /* Then try to fetch string or dynamic array data */ - call_fetch(&tp->args[i].fetch, regs, dl); - /* Reduce maximum length */ - end += get_rloc_len(*dl); - maxlen -= get_rloc_len(*dl); - /* Trick here, convert data_rloc to data_loc */ - *dl = convert_rloc_to_loc(*dl, - ent_size + tp->args[i].offset); - } else - /* Just fetching data normally */ - call_fetch(&tp->args[i].fetch, regs, - data + tp->args[i].offset); - } -} - /* Kprobe handler */ static __kprobes void -__kprobe_trace_func(struct trace_probe *tp, struct pt_regs *regs, +__kprobe_trace_func(struct trace_kprobe *tk, struct pt_regs *regs, struct ftrace_event_file *ftrace_file) { struct kprobe_trace_entry_head *entry; @@ -812,18 +929,18 @@ __kprobe_trace_func(struct trace_probe *tp, struct pt_regs *regs, struct ring_buffer *buffer; int size, dsize, pc; unsigned long irq_flags; - struct ftrace_event_call *call = &tp->call; + struct ftrace_event_call *call = &tk->tp.call; WARN_ON(call != ftrace_file->event_call); - if (test_bit(FTRACE_EVENT_FL_SOFT_DISABLED_BIT, &ftrace_file->flags)) + if (ftrace_trigger_soft_disabled(ftrace_file)) return; local_save_flags(irq_flags); pc = preempt_count(); - dsize = __get_data_size(tp, regs); - size = sizeof(*entry) + tp->size + dsize; + dsize = __get_data_size(&tk->tp, regs); + size = sizeof(*entry) + tk->tp.size + dsize; event = trace_event_buffer_lock_reserve(&buffer, ftrace_file, call->event.type, @@ -832,26 +949,25 @@ __kprobe_trace_func(struct trace_probe *tp, struct pt_regs *regs, return; entry = ring_buffer_event_data(event); - entry->ip = (unsigned long)tp->rp.kp.addr; - store_trace_args(sizeof(*entry), tp, regs, (u8 *)&entry[1], dsize); + entry->ip = (unsigned long)tk->rp.kp.addr; + store_trace_args(sizeof(*entry), &tk->tp, regs, (u8 *)&entry[1], dsize); - if (!filter_check_discard(ftrace_file, entry, buffer, event)) - trace_buffer_unlock_commit_regs(buffer, event, - irq_flags, pc, regs); + event_trigger_unlock_commit_regs(ftrace_file, buffer, event, + entry, irq_flags, pc, regs); } static __kprobes void -kprobe_trace_func(struct trace_probe *tp, struct pt_regs *regs) +kprobe_trace_func(struct trace_kprobe *tk, struct pt_regs *regs) { struct event_file_link *link; - list_for_each_entry_rcu(link, &tp->files, list) - __kprobe_trace_func(tp, regs, link->file); + list_for_each_entry_rcu(link, &tk->tp.files, list) + __kprobe_trace_func(tk, regs, link->file); } /* Kretprobe handler */ static __kprobes void -__kretprobe_trace_func(struct trace_probe *tp, struct kretprobe_instance *ri, +__kretprobe_trace_func(struct trace_kprobe *tk, struct kretprobe_instance *ri, struct pt_regs *regs, struct ftrace_event_file *ftrace_file) { @@ -860,18 +976,18 @@ __kretprobe_trace_func(struct trace_probe *tp, struct kretprobe_instance *ri, struct ring_buffer *buffer; int size, pc, dsize; unsigned long irq_flags; - struct ftrace_event_call *call = &tp->call; + struct ftrace_event_call *call = &tk->tp.call; WARN_ON(call != ftrace_file->event_call); - if (test_bit(FTRACE_EVENT_FL_SOFT_DISABLED_BIT, &ftrace_file->flags)) + if (ftrace_trigger_soft_disabled(ftrace_file)) return; local_save_flags(irq_flags); pc = preempt_count(); - dsize = __get_data_size(tp, regs); - size = sizeof(*entry) + tp->size + dsize; + dsize = __get_data_size(&tk->tp, regs); + size = sizeof(*entry) + tk->tp.size + dsize; event = trace_event_buffer_lock_reserve(&buffer, ftrace_file, call->event.type, @@ -880,23 +996,22 @@ __kretprobe_trace_func(struct trace_probe *tp, struct kretprobe_instance *ri, return; entry = ring_buffer_event_data(event); - entry->func = (unsigned long)tp->rp.kp.addr; + entry->func = (unsigned long)tk->rp.kp.addr; entry->ret_ip = (unsigned long)ri->ret_addr; - store_trace_args(sizeof(*entry), tp, regs, (u8 *)&entry[1], dsize); + store_trace_args(sizeof(*entry), &tk->tp, regs, (u8 *)&entry[1], dsize); - if (!filter_check_discard(ftrace_file, entry, buffer, event)) - trace_buffer_unlock_commit_regs(buffer, event, - irq_flags, pc, regs); + event_trigger_unlock_commit_regs(ftrace_file, buffer, event, + entry, irq_flags, pc, regs); } static __kprobes void -kretprobe_trace_func(struct trace_probe *tp, struct kretprobe_instance *ri, +kretprobe_trace_func(struct trace_kprobe *tk, struct kretprobe_instance *ri, struct pt_regs *regs) { struct event_file_link *link; - list_for_each_entry_rcu(link, &tp->files, list) - __kretprobe_trace_func(tp, ri, regs, link->file); + list_for_each_entry_rcu(link, &tk->tp.files, list) + __kretprobe_trace_func(tk, ri, regs, link->file); } /* Event entry printers */ @@ -983,16 +1098,18 @@ static int kprobe_event_define_fields(struct ftrace_event_call *event_call) { int ret, i; struct kprobe_trace_entry_head field; - struct trace_probe *tp = (struct trace_probe *)event_call->data; + struct trace_kprobe *tk = (struct trace_kprobe *)event_call->data; DEFINE_FIELD(unsigned long, ip, FIELD_STRING_IP, 0); /* Set argument names as fields */ - for (i = 0; i < tp->nr_args; i++) { - ret = trace_define_field(event_call, tp->args[i].type->fmttype, - tp->args[i].name, - sizeof(field) + tp->args[i].offset, - tp->args[i].type->size, - tp->args[i].type->is_signed, + for (i = 0; i < tk->tp.nr_args; i++) { + struct probe_arg *parg = &tk->tp.args[i]; + + ret = trace_define_field(event_call, parg->type->fmttype, + parg->name, + sizeof(field) + parg->offset, + parg->type->size, + parg->type->is_signed, FILTER_OTHER); if (ret) return ret; @@ -1004,17 +1121,19 @@ static int kretprobe_event_define_fields(struct ftrace_event_call *event_call) { int ret, i; struct kretprobe_trace_entry_head field; - struct trace_probe *tp = (struct trace_probe *)event_call->data; + struct trace_kprobe *tk = (struct trace_kprobe *)event_call->data; DEFINE_FIELD(unsigned long, func, FIELD_STRING_FUNC, 0); DEFINE_FIELD(unsigned long, ret_ip, FIELD_STRING_RETIP, 0); /* Set argument names as fields */ - for (i = 0; i < tp->nr_args; i++) { - ret = trace_define_field(event_call, tp->args[i].type->fmttype, - tp->args[i].name, - sizeof(field) + tp->args[i].offset, - tp->args[i].type->size, - tp->args[i].type->is_signed, + for (i = 0; i < tk->tp.nr_args; i++) { + struct probe_arg *parg = &tk->tp.args[i]; + + ret = trace_define_field(event_call, parg->type->fmttype, + parg->name, + sizeof(field) + parg->offset, + parg->type->size, + parg->type->is_signed, FILTER_OTHER); if (ret) return ret; @@ -1022,74 +1141,13 @@ static int kretprobe_event_define_fields(struct ftrace_event_call *event_call) return 0; } -static int __set_print_fmt(struct trace_probe *tp, char *buf, int len) -{ - int i; - int pos = 0; - - const char *fmt, *arg; - - if (!trace_probe_is_return(tp)) { - fmt = "(%lx)"; - arg = "REC->" FIELD_STRING_IP; - } else { - fmt = "(%lx <- %lx)"; - arg = "REC->" FIELD_STRING_FUNC ", REC->" FIELD_STRING_RETIP; - } - - /* When len=0, we just calculate the needed length */ -#define LEN_OR_ZERO (len ? len - pos : 0) - - pos += snprintf(buf + pos, LEN_OR_ZERO, "\"%s", fmt); - - for (i = 0; i < tp->nr_args; i++) { - pos += snprintf(buf + pos, LEN_OR_ZERO, " %s=%s", - tp->args[i].name, tp->args[i].type->fmt); - } - - pos += snprintf(buf + pos, LEN_OR_ZERO, "\", %s", arg); - - for (i = 0; i < tp->nr_args; i++) { - if (strcmp(tp->args[i].type->name, "string") == 0) - pos += snprintf(buf + pos, LEN_OR_ZERO, - ", __get_str(%s)", - tp->args[i].name); - else - pos += snprintf(buf + pos, LEN_OR_ZERO, ", REC->%s", - tp->args[i].name); - } - -#undef LEN_OR_ZERO - - /* return the length of print_fmt */ - return pos; -} - -static int set_print_fmt(struct trace_probe *tp) -{ - int len; - char *print_fmt; - - /* First: called with 0 length to calculate the needed length */ - len = __set_print_fmt(tp, NULL, 0); - print_fmt = kmalloc(len + 1, GFP_KERNEL); - if (!print_fmt) - return -ENOMEM; - - /* Second: actually write the @print_fmt */ - __set_print_fmt(tp, print_fmt, len + 1); - tp->call.print_fmt = print_fmt; - - return 0; -} - #ifdef CONFIG_PERF_EVENTS /* Kprobe profile handler */ static __kprobes void -kprobe_perf_func(struct trace_probe *tp, struct pt_regs *regs) +kprobe_perf_func(struct trace_kprobe *tk, struct pt_regs *regs) { - struct ftrace_event_call *call = &tp->call; + struct ftrace_event_call *call = &tk->tp.call; struct kprobe_trace_entry_head *entry; struct hlist_head *head; int size, __size, dsize; @@ -1099,8 +1157,8 @@ kprobe_perf_func(struct trace_probe *tp, struct pt_regs *regs) if (hlist_empty(head)) return; - dsize = __get_data_size(tp, regs); - __size = sizeof(*entry) + tp->size + dsize; + dsize = __get_data_size(&tk->tp, regs); + __size = sizeof(*entry) + tk->tp.size + dsize; size = ALIGN(__size + sizeof(u32), sizeof(u64)); size -= sizeof(u32); @@ -1108,18 +1166,18 @@ kprobe_perf_func(struct trace_probe *tp, struct pt_regs *regs) if (!entry) return; - entry->ip = (unsigned long)tp->rp.kp.addr; + entry->ip = (unsigned long)tk->rp.kp.addr; memset(&entry[1], 0, dsize); - store_trace_args(sizeof(*entry), tp, regs, (u8 *)&entry[1], dsize); + store_trace_args(sizeof(*entry), &tk->tp, regs, (u8 *)&entry[1], dsize); perf_trace_buf_submit(entry, size, rctx, 0, 1, regs, head, NULL); } /* Kretprobe profile handler */ static __kprobes void -kretprobe_perf_func(struct trace_probe *tp, struct kretprobe_instance *ri, +kretprobe_perf_func(struct trace_kprobe *tk, struct kretprobe_instance *ri, struct pt_regs *regs) { - struct ftrace_event_call *call = &tp->call; + struct ftrace_event_call *call = &tk->tp.call; struct kretprobe_trace_entry_head *entry; struct hlist_head *head; int size, __size, dsize; @@ -1129,8 +1187,8 @@ kretprobe_perf_func(struct trace_probe *tp, struct kretprobe_instance *ri, if (hlist_empty(head)) return; - dsize = __get_data_size(tp, regs); - __size = sizeof(*entry) + tp->size + dsize; + dsize = __get_data_size(&tk->tp, regs); + __size = sizeof(*entry) + tk->tp.size + dsize; size = ALIGN(__size + sizeof(u32), sizeof(u64)); size -= sizeof(u32); @@ -1138,9 +1196,9 @@ kretprobe_perf_func(struct trace_probe *tp, struct kretprobe_instance *ri, if (!entry) return; - entry->func = (unsigned long)tp->rp.kp.addr; + entry->func = (unsigned long)tk->rp.kp.addr; entry->ret_ip = (unsigned long)ri->ret_addr; - store_trace_args(sizeof(*entry), tp, regs, (u8 *)&entry[1], dsize); + store_trace_args(sizeof(*entry), &tk->tp, regs, (u8 *)&entry[1], dsize); perf_trace_buf_submit(entry, size, rctx, 0, 1, regs, head, NULL); } #endif /* CONFIG_PERF_EVENTS */ @@ -1155,20 +1213,20 @@ static __kprobes int kprobe_register(struct ftrace_event_call *event, enum trace_reg type, void *data) { - struct trace_probe *tp = (struct trace_probe *)event->data; + struct trace_kprobe *tk = (struct trace_kprobe *)event->data; struct ftrace_event_file *file = data; switch (type) { case TRACE_REG_REGISTER: - return enable_trace_probe(tp, file); + return enable_trace_kprobe(tk, file); case TRACE_REG_UNREGISTER: - return disable_trace_probe(tp, file); + return disable_trace_kprobe(tk, file); #ifdef CONFIG_PERF_EVENTS case TRACE_REG_PERF_REGISTER: - return enable_trace_probe(tp, NULL); + return enable_trace_kprobe(tk, NULL); case TRACE_REG_PERF_UNREGISTER: - return disable_trace_probe(tp, NULL); + return disable_trace_kprobe(tk, NULL); case TRACE_REG_PERF_OPEN: case TRACE_REG_PERF_CLOSE: case TRACE_REG_PERF_ADD: @@ -1182,15 +1240,15 @@ int kprobe_register(struct ftrace_event_call *event, static __kprobes int kprobe_dispatcher(struct kprobe *kp, struct pt_regs *regs) { - struct trace_probe *tp = container_of(kp, struct trace_probe, rp.kp); + struct trace_kprobe *tk = container_of(kp, struct trace_kprobe, rp.kp); - tp->nhit++; + tk->nhit++; - if (tp->flags & TP_FLAG_TRACE) - kprobe_trace_func(tp, regs); + if (tk->tp.flags & TP_FLAG_TRACE) + kprobe_trace_func(tk, regs); #ifdef CONFIG_PERF_EVENTS - if (tp->flags & TP_FLAG_PROFILE) - kprobe_perf_func(tp, regs); + if (tk->tp.flags & TP_FLAG_PROFILE) + kprobe_perf_func(tk, regs); #endif return 0; /* We don't tweek kernel, so just return 0 */ } @@ -1198,15 +1256,15 @@ int kprobe_dispatcher(struct kprobe *kp, struct pt_regs *regs) static __kprobes int kretprobe_dispatcher(struct kretprobe_instance *ri, struct pt_regs *regs) { - struct trace_probe *tp = container_of(ri->rp, struct trace_probe, rp); + struct trace_kprobe *tk = container_of(ri->rp, struct trace_kprobe, rp); - tp->nhit++; + tk->nhit++; - if (tp->flags & TP_FLAG_TRACE) - kretprobe_trace_func(tp, ri, regs); + if (tk->tp.flags & TP_FLAG_TRACE) + kretprobe_trace_func(tk, ri, regs); #ifdef CONFIG_PERF_EVENTS - if (tp->flags & TP_FLAG_PROFILE) - kretprobe_perf_func(tp, ri, regs); + if (tk->tp.flags & TP_FLAG_PROFILE) + kretprobe_perf_func(tk, ri, regs); #endif return 0; /* We don't tweek kernel, so just return 0 */ } @@ -1219,21 +1277,21 @@ static struct trace_event_functions kprobe_funcs = { .trace = print_kprobe_event }; -static int register_probe_event(struct trace_probe *tp) +static int register_kprobe_event(struct trace_kprobe *tk) { - struct ftrace_event_call *call = &tp->call; + struct ftrace_event_call *call = &tk->tp.call; int ret; /* Initialize ftrace_event_call */ INIT_LIST_HEAD(&call->class->fields); - if (trace_probe_is_return(tp)) { + if (trace_kprobe_is_return(tk)) { call->event.funcs = &kretprobe_funcs; call->class->define_fields = kretprobe_event_define_fields; } else { call->event.funcs = &kprobe_funcs; call->class->define_fields = kprobe_event_define_fields; } - if (set_print_fmt(tp) < 0) + if (set_print_fmt(&tk->tp, trace_kprobe_is_return(tk)) < 0) return -ENOMEM; ret = register_ftrace_event(&call->event); if (!ret) { @@ -1242,7 +1300,7 @@ static int register_probe_event(struct trace_probe *tp) } call->flags = 0; call->class->reg = kprobe_register; - call->data = tp; + call->data = tk; ret = trace_add_event_call(call); if (ret) { pr_info("Failed to register kprobe event: %s\n", call->name); @@ -1252,14 +1310,14 @@ static int register_probe_event(struct trace_probe *tp) return ret; } -static int unregister_probe_event(struct trace_probe *tp) +static int unregister_kprobe_event(struct trace_kprobe *tk) { int ret; /* tp->event is unregistered in trace_remove_event_call() */ - ret = trace_remove_event_call(&tp->call); + ret = trace_remove_event_call(&tk->tp.call); if (!ret) - kfree(tp->call.print_fmt); + kfree(tk->tp.call.print_fmt); return ret; } @@ -1269,7 +1327,7 @@ static __init int init_kprobe_trace(void) struct dentry *d_tracer; struct dentry *entry; - if (register_module_notifier(&trace_probe_module_nb)) + if (register_module_notifier(&trace_kprobe_module_nb)) return -EINVAL; d_tracer = tracing_init_dentry(); @@ -1309,26 +1367,26 @@ static __used int kprobe_trace_selftest_target(int a1, int a2, int a3, } static struct ftrace_event_file * -find_trace_probe_file(struct trace_probe *tp, struct trace_array *tr) +find_trace_probe_file(struct trace_kprobe *tk, struct trace_array *tr) { struct ftrace_event_file *file; list_for_each_entry(file, &tr->events, list) - if (file->event_call == &tp->call) + if (file->event_call == &tk->tp.call) return file; return NULL; } /* - * Nobody but us can call enable_trace_probe/disable_trace_probe at this + * Nobody but us can call enable_trace_kprobe/disable_trace_kprobe at this * stage, we can do this lockless. */ static __init int kprobe_trace_self_tests_init(void) { int ret, warn = 0; int (*target)(int, int, int, int, int, int); - struct trace_probe *tp; + struct trace_kprobe *tk; struct ftrace_event_file *file; target = kprobe_trace_selftest_target; @@ -1337,44 +1395,44 @@ static __init int kprobe_trace_self_tests_init(void) ret = traceprobe_command("p:testprobe kprobe_trace_selftest_target " "$stack $stack0 +0($stack)", - create_trace_probe); + create_trace_kprobe); if (WARN_ON_ONCE(ret)) { pr_warn("error on probing function entry.\n"); warn++; } else { /* Enable trace point */ - tp = find_trace_probe("testprobe", KPROBE_EVENT_SYSTEM); - if (WARN_ON_ONCE(tp == NULL)) { + tk = find_trace_kprobe("testprobe", KPROBE_EVENT_SYSTEM); + if (WARN_ON_ONCE(tk == NULL)) { pr_warn("error on getting new probe.\n"); warn++; } else { - file = find_trace_probe_file(tp, top_trace_array()); + file = find_trace_probe_file(tk, top_trace_array()); if (WARN_ON_ONCE(file == NULL)) { pr_warn("error on getting probe file.\n"); warn++; } else - enable_trace_probe(tp, file); + enable_trace_kprobe(tk, file); } } ret = traceprobe_command("r:testprobe2 kprobe_trace_selftest_target " - "$retval", create_trace_probe); + "$retval", create_trace_kprobe); if (WARN_ON_ONCE(ret)) { pr_warn("error on probing function return.\n"); warn++; } else { /* Enable trace point */ - tp = find_trace_probe("testprobe2", KPROBE_EVENT_SYSTEM); - if (WARN_ON_ONCE(tp == NULL)) { + tk = find_trace_kprobe("testprobe2", KPROBE_EVENT_SYSTEM); + if (WARN_ON_ONCE(tk == NULL)) { pr_warn("error on getting 2nd new probe.\n"); warn++; } else { - file = find_trace_probe_file(tp, top_trace_array()); + file = find_trace_probe_file(tk, top_trace_array()); if (WARN_ON_ONCE(file == NULL)) { pr_warn("error on getting probe file.\n"); warn++; } else - enable_trace_probe(tp, file); + enable_trace_kprobe(tk, file); } } @@ -1384,46 +1442,46 @@ static __init int kprobe_trace_self_tests_init(void) ret = target(1, 2, 3, 4, 5, 6); /* Disable trace points before removing it */ - tp = find_trace_probe("testprobe", KPROBE_EVENT_SYSTEM); - if (WARN_ON_ONCE(tp == NULL)) { + tk = find_trace_kprobe("testprobe", KPROBE_EVENT_SYSTEM); + if (WARN_ON_ONCE(tk == NULL)) { pr_warn("error on getting test probe.\n"); warn++; } else { - file = find_trace_probe_file(tp, top_trace_array()); + file = find_trace_probe_file(tk, top_trace_array()); if (WARN_ON_ONCE(file == NULL)) { pr_warn("error on getting probe file.\n"); warn++; } else - disable_trace_probe(tp, file); + disable_trace_kprobe(tk, file); } - tp = find_trace_probe("testprobe2", KPROBE_EVENT_SYSTEM); - if (WARN_ON_ONCE(tp == NULL)) { + tk = find_trace_kprobe("testprobe2", KPROBE_EVENT_SYSTEM); + if (WARN_ON_ONCE(tk == NULL)) { pr_warn("error on getting 2nd test probe.\n"); warn++; } else { - file = find_trace_probe_file(tp, top_trace_array()); + file = find_trace_probe_file(tk, top_trace_array()); if (WARN_ON_ONCE(file == NULL)) { pr_warn("error on getting probe file.\n"); warn++; } else - disable_trace_probe(tp, file); + disable_trace_kprobe(tk, file); } - ret = traceprobe_command("-:testprobe", create_trace_probe); + ret = traceprobe_command("-:testprobe", create_trace_kprobe); if (WARN_ON_ONCE(ret)) { pr_warn("error on deleting a probe.\n"); warn++; } - ret = traceprobe_command("-:testprobe2", create_trace_probe); + ret = traceprobe_command("-:testprobe2", create_trace_kprobe); if (WARN_ON_ONCE(ret)) { pr_warn("error on deleting a probe.\n"); warn++; } end: - release_all_trace_probes(); + release_all_trace_kprobes(); if (warn) pr_cont("NG: Some tests are failed. Please check them.\n"); else diff --git a/kernel/trace/trace_probe.c b/kernel/trace/trace_probe.c index 412e959709b4..8364a421b4df 100644 --- a/kernel/trace/trace_probe.c +++ b/kernel/trace/trace_probe.c @@ -35,46 +35,27 @@ const char *reserved_field_names[] = { FIELD_STRING_FUNC, }; -/* Printing function type */ -#define PRINT_TYPE_FUNC_NAME(type) print_type_##type -#define PRINT_TYPE_FMT_NAME(type) print_type_format_##type - /* Printing in basic type function template */ -#define DEFINE_BASIC_PRINT_TYPE_FUNC(type, fmt, cast) \ -static __kprobes int PRINT_TYPE_FUNC_NAME(type)(struct trace_seq *s, \ +#define DEFINE_BASIC_PRINT_TYPE_FUNC(type, fmt) \ +__kprobes int PRINT_TYPE_FUNC_NAME(type)(struct trace_seq *s, \ const char *name, \ - void *data, void *ent)\ + void *data, void *ent) \ { \ - return trace_seq_printf(s, " %s=" fmt, name, (cast)*(type *)data);\ + return trace_seq_printf(s, " %s=" fmt, name, *(type *)data); \ } \ -static const char PRINT_TYPE_FMT_NAME(type)[] = fmt; - -DEFINE_BASIC_PRINT_TYPE_FUNC(u8, "%x", unsigned int) -DEFINE_BASIC_PRINT_TYPE_FUNC(u16, "%x", unsigned int) -DEFINE_BASIC_PRINT_TYPE_FUNC(u32, "%lx", unsigned long) -DEFINE_BASIC_PRINT_TYPE_FUNC(u64, "%llx", unsigned long long) -DEFINE_BASIC_PRINT_TYPE_FUNC(s8, "%d", int) -DEFINE_BASIC_PRINT_TYPE_FUNC(s16, "%d", int) -DEFINE_BASIC_PRINT_TYPE_FUNC(s32, "%ld", long) -DEFINE_BASIC_PRINT_TYPE_FUNC(s64, "%lld", long long) - -static inline void *get_rloc_data(u32 *dl) -{ - return (u8 *)dl + get_rloc_offs(*dl); -} +const char PRINT_TYPE_FMT_NAME(type)[] = fmt; -/* For data_loc conversion */ -static inline void *get_loc_data(u32 *dl, void *ent) -{ - return (u8 *)ent + get_rloc_offs(*dl); -} - -/* For defining macros, define string/string_size types */ -typedef u32 string; -typedef u32 string_size; +DEFINE_BASIC_PRINT_TYPE_FUNC(u8 , "0x%x") +DEFINE_BASIC_PRINT_TYPE_FUNC(u16, "0x%x") +DEFINE_BASIC_PRINT_TYPE_FUNC(u32, "0x%x") +DEFINE_BASIC_PRINT_TYPE_FUNC(u64, "0x%Lx") +DEFINE_BASIC_PRINT_TYPE_FUNC(s8, "%d") +DEFINE_BASIC_PRINT_TYPE_FUNC(s16, "%d") +DEFINE_BASIC_PRINT_TYPE_FUNC(s32, "%d") +DEFINE_BASIC_PRINT_TYPE_FUNC(s64, "%Ld") /* Print type function for string type */ -static __kprobes int PRINT_TYPE_FUNC_NAME(string)(struct trace_seq *s, +__kprobes int PRINT_TYPE_FUNC_NAME(string)(struct trace_seq *s, const char *name, void *data, void *ent) { @@ -87,18 +68,7 @@ static __kprobes int PRINT_TYPE_FUNC_NAME(string)(struct trace_seq *s, (const char *)get_loc_data(data, ent)); } -static const char PRINT_TYPE_FMT_NAME(string)[] = "\\\"%s\\\""; - -#define FETCH_FUNC_NAME(method, type) fetch_##method##_##type -/* - * Define macro for basic types - we don't need to define s* types, because - * we have to care only about bitwidth at recording time. - */ -#define DEFINE_BASIC_FETCH_FUNCS(method) \ -DEFINE_FETCH_##method(u8) \ -DEFINE_FETCH_##method(u16) \ -DEFINE_FETCH_##method(u32) \ -DEFINE_FETCH_##method(u64) +const char PRINT_TYPE_FMT_NAME(string)[] = "\\\"%s\\\""; #define CHECK_FETCH_FUNCS(method, fn) \ (((FETCH_FUNC_NAME(method, u8) == fn) || \ @@ -111,7 +81,7 @@ DEFINE_FETCH_##method(u64) /* Data fetch function templates */ #define DEFINE_FETCH_reg(type) \ -static __kprobes void FETCH_FUNC_NAME(reg, type)(struct pt_regs *regs, \ +__kprobes void FETCH_FUNC_NAME(reg, type)(struct pt_regs *regs, \ void *offset, void *dest) \ { \ *(type *)dest = (type)regs_get_register(regs, \ @@ -122,20 +92,8 @@ DEFINE_BASIC_FETCH_FUNCS(reg) #define fetch_reg_string NULL #define fetch_reg_string_size NULL -#define DEFINE_FETCH_stack(type) \ -static __kprobes void FETCH_FUNC_NAME(stack, type)(struct pt_regs *regs,\ - void *offset, void *dest) \ -{ \ - *(type *)dest = (type)regs_get_kernel_stack_nth(regs, \ - (unsigned int)((unsigned long)offset)); \ -} -DEFINE_BASIC_FETCH_FUNCS(stack) -/* No string on the stack entry */ -#define fetch_stack_string NULL -#define fetch_stack_string_size NULL - #define DEFINE_FETCH_retval(type) \ -static __kprobes void FETCH_FUNC_NAME(retval, type)(struct pt_regs *regs,\ +__kprobes void FETCH_FUNC_NAME(retval, type)(struct pt_regs *regs, \ void *dummy, void *dest) \ { \ *(type *)dest = (type)regs_return_value(regs); \ @@ -145,150 +103,16 @@ DEFINE_BASIC_FETCH_FUNCS(retval) #define fetch_retval_string NULL #define fetch_retval_string_size NULL -#define DEFINE_FETCH_memory(type) \ -static __kprobes void FETCH_FUNC_NAME(memory, type)(struct pt_regs *regs,\ - void *addr, void *dest) \ -{ \ - type retval; \ - if (probe_kernel_address(addr, retval)) \ - *(type *)dest = 0; \ - else \ - *(type *)dest = retval; \ -} -DEFINE_BASIC_FETCH_FUNCS(memory) -/* - * Fetch a null-terminated string. Caller MUST set *(u32 *)dest with max - * length and relative data location. - */ -static __kprobes void FETCH_FUNC_NAME(memory, string)(struct pt_regs *regs, - void *addr, void *dest) -{ - long ret; - int maxlen = get_rloc_len(*(u32 *)dest); - u8 *dst = get_rloc_data(dest); - u8 *src = addr; - mm_segment_t old_fs = get_fs(); - - if (!maxlen) - return; - - /* - * Try to get string again, since the string can be changed while - * probing. - */ - set_fs(KERNEL_DS); - pagefault_disable(); - - do - ret = __copy_from_user_inatomic(dst++, src++, 1); - while (dst[-1] && ret == 0 && src - (u8 *)addr < maxlen); - - dst[-1] = '\0'; - pagefault_enable(); - set_fs(old_fs); - - if (ret < 0) { /* Failed to fetch string */ - ((u8 *)get_rloc_data(dest))[0] = '\0'; - *(u32 *)dest = make_data_rloc(0, get_rloc_offs(*(u32 *)dest)); - } else { - *(u32 *)dest = make_data_rloc(src - (u8 *)addr, - get_rloc_offs(*(u32 *)dest)); - } -} - -/* Return the length of string -- including null terminal byte */ -static __kprobes void FETCH_FUNC_NAME(memory, string_size)(struct pt_regs *regs, - void *addr, void *dest) -{ - mm_segment_t old_fs; - int ret, len = 0; - u8 c; - - old_fs = get_fs(); - set_fs(KERNEL_DS); - pagefault_disable(); - - do { - ret = __copy_from_user_inatomic(&c, (u8 *)addr + len, 1); - len++; - } while (c && ret == 0 && len < MAX_STRING_SIZE); - - pagefault_enable(); - set_fs(old_fs); - - if (ret < 0) /* Failed to check the length */ - *(u32 *)dest = 0; - else - *(u32 *)dest = len; -} - -/* Memory fetching by symbol */ -struct symbol_cache { - char *symbol; - long offset; - unsigned long addr; -}; - -static unsigned long update_symbol_cache(struct symbol_cache *sc) -{ - sc->addr = (unsigned long)kallsyms_lookup_name(sc->symbol); - - if (sc->addr) - sc->addr += sc->offset; - - return sc->addr; -} - -static void free_symbol_cache(struct symbol_cache *sc) -{ - kfree(sc->symbol); - kfree(sc); -} - -static struct symbol_cache *alloc_symbol_cache(const char *sym, long offset) -{ - struct symbol_cache *sc; - - if (!sym || strlen(sym) == 0) - return NULL; - - sc = kzalloc(sizeof(struct symbol_cache), GFP_KERNEL); - if (!sc) - return NULL; - - sc->symbol = kstrdup(sym, GFP_KERNEL); - if (!sc->symbol) { - kfree(sc); - return NULL; - } - sc->offset = offset; - update_symbol_cache(sc); - - return sc; -} - -#define DEFINE_FETCH_symbol(type) \ -static __kprobes void FETCH_FUNC_NAME(symbol, type)(struct pt_regs *regs,\ - void *data, void *dest) \ -{ \ - struct symbol_cache *sc = data; \ - if (sc->addr) \ - fetch_memory_##type(regs, (void *)sc->addr, dest); \ - else \ - *(type *)dest = 0; \ -} -DEFINE_BASIC_FETCH_FUNCS(symbol) -DEFINE_FETCH_symbol(string) -DEFINE_FETCH_symbol(string_size) - /* Dereference memory access function */ struct deref_fetch_param { struct fetch_param orig; long offset; + fetch_func_t fetch; + fetch_func_t fetch_size; }; #define DEFINE_FETCH_deref(type) \ -static __kprobes void FETCH_FUNC_NAME(deref, type)(struct pt_regs *regs,\ +__kprobes void FETCH_FUNC_NAME(deref, type)(struct pt_regs *regs, \ void *data, void *dest) \ { \ struct deref_fetch_param *dprm = data; \ @@ -296,13 +120,26 @@ static __kprobes void FETCH_FUNC_NAME(deref, type)(struct pt_regs *regs,\ call_fetch(&dprm->orig, regs, &addr); \ if (addr) { \ addr += dprm->offset; \ - fetch_memory_##type(regs, (void *)addr, dest); \ + dprm->fetch(regs, (void *)addr, dest); \ } else \ *(type *)dest = 0; \ } DEFINE_BASIC_FETCH_FUNCS(deref) DEFINE_FETCH_deref(string) -DEFINE_FETCH_deref(string_size) + +__kprobes void FETCH_FUNC_NAME(deref, string_size)(struct pt_regs *regs, + void *data, void *dest) +{ + struct deref_fetch_param *dprm = data; + unsigned long addr; + + call_fetch(&dprm->orig, regs, &addr); + if (addr && dprm->fetch_size) { + addr += dprm->offset; + dprm->fetch_size(regs, (void *)addr, dest); + } else + *(string_size *)dest = 0; +} static __kprobes void update_deref_fetch_param(struct deref_fetch_param *data) { @@ -329,7 +166,7 @@ struct bitfield_fetch_param { }; #define DEFINE_FETCH_bitfield(type) \ -static __kprobes void FETCH_FUNC_NAME(bitfield, type)(struct pt_regs *regs,\ +__kprobes void FETCH_FUNC_NAME(bitfield, type)(struct pt_regs *regs, \ void *data, void *dest) \ { \ struct bitfield_fetch_param *bprm = data; \ @@ -374,58 +211,8 @@ free_bitfield_fetch_param(struct bitfield_fetch_param *data) kfree(data); } -/* Default (unsigned long) fetch type */ -#define __DEFAULT_FETCH_TYPE(t) u##t -#define _DEFAULT_FETCH_TYPE(t) __DEFAULT_FETCH_TYPE(t) -#define DEFAULT_FETCH_TYPE _DEFAULT_FETCH_TYPE(BITS_PER_LONG) -#define DEFAULT_FETCH_TYPE_STR __stringify(DEFAULT_FETCH_TYPE) - -#define ASSIGN_FETCH_FUNC(method, type) \ - [FETCH_MTD_##method] = FETCH_FUNC_NAME(method, type) - -#define __ASSIGN_FETCH_TYPE(_name, ptype, ftype, _size, sign, _fmttype) \ - {.name = _name, \ - .size = _size, \ - .is_signed = sign, \ - .print = PRINT_TYPE_FUNC_NAME(ptype), \ - .fmt = PRINT_TYPE_FMT_NAME(ptype), \ - .fmttype = _fmttype, \ - .fetch = { \ -ASSIGN_FETCH_FUNC(reg, ftype), \ -ASSIGN_FETCH_FUNC(stack, ftype), \ -ASSIGN_FETCH_FUNC(retval, ftype), \ -ASSIGN_FETCH_FUNC(memory, ftype), \ -ASSIGN_FETCH_FUNC(symbol, ftype), \ -ASSIGN_FETCH_FUNC(deref, ftype), \ -ASSIGN_FETCH_FUNC(bitfield, ftype), \ - } \ - } - -#define ASSIGN_FETCH_TYPE(ptype, ftype, sign) \ - __ASSIGN_FETCH_TYPE(#ptype, ptype, ftype, sizeof(ftype), sign, #ptype) - -#define FETCH_TYPE_STRING 0 -#define FETCH_TYPE_STRSIZE 1 - -/* Fetch type information table */ -static const struct fetch_type fetch_type_table[] = { - /* Special types */ - [FETCH_TYPE_STRING] = __ASSIGN_FETCH_TYPE("string", string, string, - sizeof(u32), 1, "__data_loc char[]"), - [FETCH_TYPE_STRSIZE] = __ASSIGN_FETCH_TYPE("string_size", u32, - string_size, sizeof(u32), 0, "u32"), - /* Basic types */ - ASSIGN_FETCH_TYPE(u8, u8, 0), - ASSIGN_FETCH_TYPE(u16, u16, 0), - ASSIGN_FETCH_TYPE(u32, u32, 0), - ASSIGN_FETCH_TYPE(u64, u64, 0), - ASSIGN_FETCH_TYPE(s8, u8, 1), - ASSIGN_FETCH_TYPE(s16, u16, 1), - ASSIGN_FETCH_TYPE(s32, u32, 1), - ASSIGN_FETCH_TYPE(s64, u64, 1), -}; - -static const struct fetch_type *find_fetch_type(const char *type) +static const struct fetch_type *find_fetch_type(const char *type, + const struct fetch_type *ftbl) { int i; @@ -446,44 +233,52 @@ static const struct fetch_type *find_fetch_type(const char *type) switch (bs) { case 8: - return find_fetch_type("u8"); + return find_fetch_type("u8", ftbl); case 16: - return find_fetch_type("u16"); + return find_fetch_type("u16", ftbl); case 32: - return find_fetch_type("u32"); + return find_fetch_type("u32", ftbl); case 64: - return find_fetch_type("u64"); + return find_fetch_type("u64", ftbl); default: goto fail; } } - for (i = 0; i < ARRAY_SIZE(fetch_type_table); i++) - if (strcmp(type, fetch_type_table[i].name) == 0) - return &fetch_type_table[i]; + for (i = 0; ftbl[i].name; i++) { + if (strcmp(type, ftbl[i].name) == 0) + return &ftbl[i]; + } fail: return NULL; } /* Special function : only accept unsigned long */ -static __kprobes void fetch_stack_address(struct pt_regs *regs, - void *dummy, void *dest) +static __kprobes void fetch_kernel_stack_address(struct pt_regs *regs, + void *dummy, void *dest) { *(unsigned long *)dest = kernel_stack_pointer(regs); } +static __kprobes void fetch_user_stack_address(struct pt_regs *regs, + void *dummy, void *dest) +{ + *(unsigned long *)dest = user_stack_pointer(regs); +} + static fetch_func_t get_fetch_size_function(const struct fetch_type *type, - fetch_func_t orig_fn) + fetch_func_t orig_fn, + const struct fetch_type *ftbl) { int i; - if (type != &fetch_type_table[FETCH_TYPE_STRING]) + if (type != &ftbl[FETCH_TYPE_STRING]) return NULL; /* Only string type needs size function */ for (i = 0; i < FETCH_MTD_END; i++) if (type->fetch[i] == orig_fn) - return fetch_type_table[FETCH_TYPE_STRSIZE].fetch[i]; + return ftbl[FETCH_TYPE_STRSIZE].fetch[i]; WARN_ON(1); /* This should not happen */ @@ -516,7 +311,8 @@ int traceprobe_split_symbol_offset(char *symbol, unsigned long *offset) #define PARAM_MAX_STACK (THREAD_SIZE / sizeof(unsigned long)) static int parse_probe_vars(char *arg, const struct fetch_type *t, - struct fetch_param *f, bool is_return) + struct fetch_param *f, bool is_return, + bool is_kprobe) { int ret = 0; unsigned long param; @@ -528,13 +324,16 @@ static int parse_probe_vars(char *arg, const struct fetch_type *t, ret = -EINVAL; } else if (strncmp(arg, "stack", 5) == 0) { if (arg[5] == '\0') { - if (strcmp(t->name, DEFAULT_FETCH_TYPE_STR) == 0) - f->fn = fetch_stack_address; + if (strcmp(t->name, DEFAULT_FETCH_TYPE_STR)) + return -EINVAL; + + if (is_kprobe) + f->fn = fetch_kernel_stack_address; else - ret = -EINVAL; + f->fn = fetch_user_stack_address; } else if (isdigit(arg[5])) { ret = kstrtoul(arg + 5, 10, ¶m); - if (ret || param > PARAM_MAX_STACK) + if (ret || (is_kprobe && param > PARAM_MAX_STACK)) ret = -EINVAL; else { f->fn = t->fetch[FETCH_MTD_stack]; @@ -552,20 +351,18 @@ static int parse_probe_vars(char *arg, const struct fetch_type *t, static int parse_probe_arg(char *arg, const struct fetch_type *t, struct fetch_param *f, bool is_return, bool is_kprobe) { + const struct fetch_type *ftbl; unsigned long param; long offset; char *tmp; - int ret; - - ret = 0; + int ret = 0; - /* Until uprobe_events supports only reg arguments */ - if (!is_kprobe && arg[0] != '%') - return -EINVAL; + ftbl = is_kprobe ? kprobes_fetch_type_table : uprobes_fetch_type_table; + BUG_ON(ftbl == NULL); switch (arg[0]) { case '$': - ret = parse_probe_vars(arg + 1, t, f, is_return); + ret = parse_probe_vars(arg + 1, t, f, is_return, is_kprobe); break; case '%': /* named register */ @@ -577,7 +374,7 @@ static int parse_probe_arg(char *arg, const struct fetch_type *t, } break; - case '@': /* memory or symbol */ + case '@': /* memory, file-offset or symbol */ if (isdigit(arg[1])) { ret = kstrtoul(arg + 1, 0, ¶m); if (ret) @@ -585,7 +382,22 @@ static int parse_probe_arg(char *arg, const struct fetch_type *t, f->fn = t->fetch[FETCH_MTD_memory]; f->data = (void *)param; + } else if (arg[1] == '+') { + /* kprobes don't support file offsets */ + if (is_kprobe) + return -EINVAL; + + ret = kstrtol(arg + 2, 0, &offset); + if (ret) + break; + + f->fn = t->fetch[FETCH_MTD_file_offset]; + f->data = (void *)offset; } else { + /* uprobes don't support symbols */ + if (!is_kprobe) + return -EINVAL; + ret = traceprobe_split_symbol_offset(arg + 1, &offset); if (ret) break; @@ -616,7 +428,7 @@ static int parse_probe_arg(char *arg, const struct fetch_type *t, struct deref_fetch_param *dprm; const struct fetch_type *t2; - t2 = find_fetch_type(NULL); + t2 = find_fetch_type(NULL, ftbl); *tmp = '\0'; dprm = kzalloc(sizeof(struct deref_fetch_param), GFP_KERNEL); @@ -624,6 +436,9 @@ static int parse_probe_arg(char *arg, const struct fetch_type *t, return -ENOMEM; dprm->offset = offset; + dprm->fetch = t->fetch[FETCH_MTD_memory]; + dprm->fetch_size = get_fetch_size_function(t, + dprm->fetch, ftbl); ret = parse_probe_arg(arg, t2, &dprm->orig, is_return, is_kprobe); if (ret) @@ -685,9 +500,13 @@ static int __parse_bitfield_probe_arg(const char *bf, int traceprobe_parse_probe_arg(char *arg, ssize_t *size, struct probe_arg *parg, bool is_return, bool is_kprobe) { + const struct fetch_type *ftbl; const char *t; int ret; + ftbl = is_kprobe ? kprobes_fetch_type_table : uprobes_fetch_type_table; + BUG_ON(ftbl == NULL); + if (strlen(arg) > MAX_ARGSTR_LEN) { pr_info("Argument is too long.: %s\n", arg); return -ENOSPC; @@ -702,7 +521,7 @@ int traceprobe_parse_probe_arg(char *arg, ssize_t *size, arg[t - parg->comm] = '\0'; t++; } - parg->type = find_fetch_type(t); + parg->type = find_fetch_type(t, ftbl); if (!parg->type) { pr_info("Unsupported type: %s\n", t); return -EINVAL; @@ -716,7 +535,8 @@ int traceprobe_parse_probe_arg(char *arg, ssize_t *size, if (ret >= 0) { parg->fetch_size.fn = get_fetch_size_function(parg->type, - parg->fetch.fn); + parg->fetch.fn, + ftbl); parg->fetch_size.data = parg->fetch.data; } @@ -837,3 +657,65 @@ out: return ret; } + +static int __set_print_fmt(struct trace_probe *tp, char *buf, int len, + bool is_return) +{ + int i; + int pos = 0; + + const char *fmt, *arg; + + if (!is_return) { + fmt = "(%lx)"; + arg = "REC->" FIELD_STRING_IP; + } else { + fmt = "(%lx <- %lx)"; + arg = "REC->" FIELD_STRING_FUNC ", REC->" FIELD_STRING_RETIP; + } + + /* When len=0, we just calculate the needed length */ +#define LEN_OR_ZERO (len ? len - pos : 0) + + pos += snprintf(buf + pos, LEN_OR_ZERO, "\"%s", fmt); + + for (i = 0; i < tp->nr_args; i++) { + pos += snprintf(buf + pos, LEN_OR_ZERO, " %s=%s", + tp->args[i].name, tp->args[i].type->fmt); + } + + pos += snprintf(buf + pos, LEN_OR_ZERO, "\", %s", arg); + + for (i = 0; i < tp->nr_args; i++) { + if (strcmp(tp->args[i].type->name, "string") == 0) + pos += snprintf(buf + pos, LEN_OR_ZERO, + ", __get_str(%s)", + tp->args[i].name); + else + pos += snprintf(buf + pos, LEN_OR_ZERO, ", REC->%s", + tp->args[i].name); + } + +#undef LEN_OR_ZERO + + /* return the length of print_fmt */ + return pos; +} + +int set_print_fmt(struct trace_probe *tp, bool is_return) +{ + int len; + char *print_fmt; + + /* First: called with 0 length to calculate the needed length */ + len = __set_print_fmt(tp, NULL, 0, is_return); + print_fmt = kmalloc(len + 1, GFP_KERNEL); + if (!print_fmt) + return -ENOMEM; + + /* Second: actually write the @print_fmt */ + __set_print_fmt(tp, print_fmt, len + 1, is_return); + tp->call.print_fmt = print_fmt; + + return 0; +} diff --git a/kernel/trace/trace_probe.h b/kernel/trace/trace_probe.h index 5c7e09d10d74..b73574a5f429 100644 --- a/kernel/trace/trace_probe.h +++ b/kernel/trace/trace_probe.h @@ -81,6 +81,17 @@ */ #define convert_rloc_to_loc(dl, offs) ((u32)(dl) + (offs)) +static inline void *get_rloc_data(u32 *dl) +{ + return (u8 *)dl + get_rloc_offs(*dl); +} + +/* For data_loc conversion */ +static inline void *get_loc_data(u32 *dl, void *ent) +{ + return (u8 *)ent + get_rloc_offs(*dl); +} + /* Data fetch function type */ typedef void (*fetch_func_t)(struct pt_regs *, void *, void *); /* Printing function type */ @@ -95,6 +106,7 @@ enum { FETCH_MTD_symbol, FETCH_MTD_deref, FETCH_MTD_bitfield, + FETCH_MTD_file_offset, FETCH_MTD_END, }; @@ -115,6 +127,148 @@ struct fetch_param { void *data; }; +/* For defining macros, define string/string_size types */ +typedef u32 string; +typedef u32 string_size; + +#define PRINT_TYPE_FUNC_NAME(type) print_type_##type +#define PRINT_TYPE_FMT_NAME(type) print_type_format_##type + +/* Printing in basic type function template */ +#define DECLARE_BASIC_PRINT_TYPE_FUNC(type) \ +__kprobes int PRINT_TYPE_FUNC_NAME(type)(struct trace_seq *s, \ + const char *name, \ + void *data, void *ent); \ +extern const char PRINT_TYPE_FMT_NAME(type)[] + +DECLARE_BASIC_PRINT_TYPE_FUNC(u8); +DECLARE_BASIC_PRINT_TYPE_FUNC(u16); +DECLARE_BASIC_PRINT_TYPE_FUNC(u32); +DECLARE_BASIC_PRINT_TYPE_FUNC(u64); +DECLARE_BASIC_PRINT_TYPE_FUNC(s8); +DECLARE_BASIC_PRINT_TYPE_FUNC(s16); +DECLARE_BASIC_PRINT_TYPE_FUNC(s32); +DECLARE_BASIC_PRINT_TYPE_FUNC(s64); +DECLARE_BASIC_PRINT_TYPE_FUNC(string); + +#define FETCH_FUNC_NAME(method, type) fetch_##method##_##type + +/* Declare macro for basic types */ +#define DECLARE_FETCH_FUNC(method, type) \ +extern void FETCH_FUNC_NAME(method, type)(struct pt_regs *regs, \ + void *data, void *dest) + +#define DECLARE_BASIC_FETCH_FUNCS(method) \ +DECLARE_FETCH_FUNC(method, u8); \ +DECLARE_FETCH_FUNC(method, u16); \ +DECLARE_FETCH_FUNC(method, u32); \ +DECLARE_FETCH_FUNC(method, u64) + +DECLARE_BASIC_FETCH_FUNCS(reg); +#define fetch_reg_string NULL +#define fetch_reg_string_size NULL + +DECLARE_BASIC_FETCH_FUNCS(retval); +#define fetch_retval_string NULL +#define fetch_retval_string_size NULL + +DECLARE_BASIC_FETCH_FUNCS(symbol); +DECLARE_FETCH_FUNC(symbol, string); +DECLARE_FETCH_FUNC(symbol, string_size); + +DECLARE_BASIC_FETCH_FUNCS(deref); +DECLARE_FETCH_FUNC(deref, string); +DECLARE_FETCH_FUNC(deref, string_size); + +DECLARE_BASIC_FETCH_FUNCS(bitfield); +#define fetch_bitfield_string NULL +#define fetch_bitfield_string_size NULL + +/* + * Define macro for basic types - we don't need to define s* types, because + * we have to care only about bitwidth at recording time. + */ +#define DEFINE_BASIC_FETCH_FUNCS(method) \ +DEFINE_FETCH_##method(u8) \ +DEFINE_FETCH_##method(u16) \ +DEFINE_FETCH_##method(u32) \ +DEFINE_FETCH_##method(u64) + +/* Default (unsigned long) fetch type */ +#define __DEFAULT_FETCH_TYPE(t) u##t +#define _DEFAULT_FETCH_TYPE(t) __DEFAULT_FETCH_TYPE(t) +#define DEFAULT_FETCH_TYPE _DEFAULT_FETCH_TYPE(BITS_PER_LONG) +#define DEFAULT_FETCH_TYPE_STR __stringify(DEFAULT_FETCH_TYPE) + +#define ASSIGN_FETCH_FUNC(method, type) \ + [FETCH_MTD_##method] = FETCH_FUNC_NAME(method, type) + +#define __ASSIGN_FETCH_TYPE(_name, ptype, ftype, _size, sign, _fmttype) \ + {.name = _name, \ + .size = _size, \ + .is_signed = sign, \ + .print = PRINT_TYPE_FUNC_NAME(ptype), \ + .fmt = PRINT_TYPE_FMT_NAME(ptype), \ + .fmttype = _fmttype, \ + .fetch = { \ +ASSIGN_FETCH_FUNC(reg, ftype), \ +ASSIGN_FETCH_FUNC(stack, ftype), \ +ASSIGN_FETCH_FUNC(retval, ftype), \ +ASSIGN_FETCH_FUNC(memory, ftype), \ +ASSIGN_FETCH_FUNC(symbol, ftype), \ +ASSIGN_FETCH_FUNC(deref, ftype), \ +ASSIGN_FETCH_FUNC(bitfield, ftype), \ +ASSIGN_FETCH_FUNC(file_offset, ftype), \ + } \ + } + +#define ASSIGN_FETCH_TYPE(ptype, ftype, sign) \ + __ASSIGN_FETCH_TYPE(#ptype, ptype, ftype, sizeof(ftype), sign, #ptype) + +#define ASSIGN_FETCH_TYPE_END {} + +#define FETCH_TYPE_STRING 0 +#define FETCH_TYPE_STRSIZE 1 + +/* + * Fetch type information table. + * It's declared as a weak symbol due to conditional compilation. + */ +extern __weak const struct fetch_type kprobes_fetch_type_table[]; +extern __weak const struct fetch_type uprobes_fetch_type_table[]; + +#ifdef CONFIG_KPROBE_EVENT +struct symbol_cache; +unsigned long update_symbol_cache(struct symbol_cache *sc); +void free_symbol_cache(struct symbol_cache *sc); +struct symbol_cache *alloc_symbol_cache(const char *sym, long offset); +#else +/* uprobes do not support symbol fetch methods */ +#define fetch_symbol_u8 NULL +#define fetch_symbol_u16 NULL +#define fetch_symbol_u32 NULL +#define fetch_symbol_u64 NULL +#define fetch_symbol_string NULL +#define fetch_symbol_string_size NULL + +struct symbol_cache { +}; +static inline unsigned long __used update_symbol_cache(struct symbol_cache *sc) +{ + return 0; +} + +static inline void __used free_symbol_cache(struct symbol_cache *sc) +{ +} + +static inline struct symbol_cache * __used +alloc_symbol_cache(const char *sym, long offset) +{ + return NULL; +} +#endif /* CONFIG_KPROBE_EVENT */ + struct probe_arg { struct fetch_param fetch; struct fetch_param fetch_size; @@ -124,6 +278,26 @@ struct probe_arg { const struct fetch_type *type; /* Type of this argument */ }; +struct trace_probe { + unsigned int flags; /* For TP_FLAG_* */ + struct ftrace_event_class class; + struct ftrace_event_call call; + struct list_head files; + ssize_t size; /* trace entry size */ + unsigned int nr_args; + struct probe_arg args[]; +}; + +static inline bool trace_probe_is_enabled(struct trace_probe *tp) +{ + return !!(tp->flags & (TP_FLAG_TRACE | TP_FLAG_PROFILE)); +} + +static inline bool trace_probe_is_registered(struct trace_probe *tp) +{ + return !!(tp->flags & TP_FLAG_REGISTERED); +} + static inline __kprobes void call_fetch(struct fetch_param *fprm, struct pt_regs *regs, void *dest) { @@ -158,3 +332,53 @@ extern ssize_t traceprobe_probes_write(struct file *file, int (*createfn)(int, char**)); extern int traceprobe_command(const char *buf, int (*createfn)(int, char**)); + +/* Sum up total data length for dynamic arraies (strings) */ +static inline __kprobes int +__get_data_size(struct trace_probe *tp, struct pt_regs *regs) +{ + int i, ret = 0; + u32 len; + + for (i = 0; i < tp->nr_args; i++) + if (unlikely(tp->args[i].fetch_size.fn)) { + call_fetch(&tp->args[i].fetch_size, regs, &len); + ret += len; + } + + return ret; +} + +/* Store the value of each argument */ +static inline __kprobes void +store_trace_args(int ent_size, struct trace_probe *tp, struct pt_regs *regs, + u8 *data, int maxlen) +{ + int i; + u32 end = tp->size; + u32 *dl; /* Data (relative) location */ + + for (i = 0; i < tp->nr_args; i++) { + if (unlikely(tp->args[i].fetch_size.fn)) { + /* + * First, we set the relative location and + * maximum data length to *dl + */ + dl = (u32 *)(data + tp->args[i].offset); + *dl = make_data_rloc(maxlen, end - tp->args[i].offset); + /* Then try to fetch string or dynamic array data */ + call_fetch(&tp->args[i].fetch, regs, dl); + /* Reduce maximum length */ + end += get_rloc_len(*dl); + maxlen -= get_rloc_len(*dl); + /* Trick here, convert data_rloc to data_loc */ + *dl = convert_rloc_to_loc(*dl, + ent_size + tp->args[i].offset); + } else + /* Just fetching data normally */ + call_fetch(&tp->args[i].fetch, regs, + data + tp->args[i].offset); + } +} + +extern int set_print_fmt(struct trace_probe *tp, bool is_return); diff --git a/kernel/trace/trace_sched_wakeup.c b/kernel/trace/trace_sched_wakeup.c index fee77e15d815..6e32635e5e57 100644 --- a/kernel/trace/trace_sched_wakeup.c +++ b/kernel/trace/trace_sched_wakeup.c @@ -16,6 +16,7 @@ #include <linux/uaccess.h> #include <linux/ftrace.h> #include <linux/sched/rt.h> +#include <linux/sched/deadline.h> #include <trace/events/sched.h> #include "trace.h" @@ -27,6 +28,8 @@ static int wakeup_cpu; static int wakeup_current_cpu; static unsigned wakeup_prio = -1; static int wakeup_rt; +static int wakeup_dl; +static int tracing_dl = 0; static arch_spinlock_t wakeup_lock = (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED; @@ -437,6 +440,7 @@ static void __wakeup_reset(struct trace_array *tr) { wakeup_cpu = -1; wakeup_prio = -1; + tracing_dl = 0; if (wakeup_task) put_task_struct(wakeup_task); @@ -472,9 +476,17 @@ probe_wakeup(void *ignore, struct task_struct *p, int success) tracing_record_cmdline(p); tracing_record_cmdline(current); - if ((wakeup_rt && !rt_task(p)) || - p->prio >= wakeup_prio || - p->prio >= current->prio) + /* + * Semantic is like this: + * - wakeup tracer handles all tasks in the system, independently + * from their scheduling class; + * - wakeup_rt tracer handles tasks belonging to sched_dl and + * sched_rt class; + * - wakeup_dl handles tasks belonging to sched_dl class only. + */ + if (tracing_dl || (wakeup_dl && !dl_task(p)) || + (wakeup_rt && !dl_task(p) && !rt_task(p)) || + (!dl_task(p) && (p->prio >= wakeup_prio || p->prio >= current->prio))) return; pc = preempt_count(); @@ -486,7 +498,8 @@ probe_wakeup(void *ignore, struct task_struct *p, int success) arch_spin_lock(&wakeup_lock); /* check for races. */ - if (!tracer_enabled || p->prio >= wakeup_prio) + if (!tracer_enabled || tracing_dl || + (!dl_task(p) && p->prio >= wakeup_prio)) goto out_locked; /* reset the trace */ @@ -496,6 +509,15 @@ probe_wakeup(void *ignore, struct task_struct *p, int success) wakeup_current_cpu = wakeup_cpu; wakeup_prio = p->prio; + /* + * Once you start tracing a -deadline task, don't bother tracing + * another task until the first one wakes up. + */ + if (dl_task(p)) + tracing_dl = 1; + else + tracing_dl = 0; + wakeup_task = p; get_task_struct(wakeup_task); @@ -597,16 +619,25 @@ static int __wakeup_tracer_init(struct trace_array *tr) static int wakeup_tracer_init(struct trace_array *tr) { + wakeup_dl = 0; wakeup_rt = 0; return __wakeup_tracer_init(tr); } static int wakeup_rt_tracer_init(struct trace_array *tr) { + wakeup_dl = 0; wakeup_rt = 1; return __wakeup_tracer_init(tr); } +static int wakeup_dl_tracer_init(struct trace_array *tr) +{ + wakeup_dl = 1; + wakeup_rt = 0; + return __wakeup_tracer_init(tr); +} + static void wakeup_tracer_reset(struct trace_array *tr) { int lat_flag = save_flags & TRACE_ITER_LATENCY_FMT; @@ -674,6 +705,28 @@ static struct tracer wakeup_rt_tracer __read_mostly = .use_max_tr = true, }; +static struct tracer wakeup_dl_tracer __read_mostly = +{ + .name = "wakeup_dl", + .init = wakeup_dl_tracer_init, + .reset = wakeup_tracer_reset, + .start = wakeup_tracer_start, + .stop = wakeup_tracer_stop, + .wait_pipe = poll_wait_pipe, + .print_max = true, + .print_header = wakeup_print_header, + .print_line = wakeup_print_line, + .flags = &tracer_flags, + .set_flag = wakeup_set_flag, + .flag_changed = wakeup_flag_changed, +#ifdef CONFIG_FTRACE_SELFTEST + .selftest = trace_selftest_startup_wakeup, +#endif + .open = wakeup_trace_open, + .close = wakeup_trace_close, + .use_max_tr = true, +}; + __init static int init_wakeup_tracer(void) { int ret; @@ -686,6 +739,10 @@ __init static int init_wakeup_tracer(void) if (ret) return ret; + ret = register_tracer(&wakeup_dl_tracer); + if (ret) + return ret; + return 0; } core_initcall(init_wakeup_tracer); diff --git a/kernel/trace/trace_selftest.c b/kernel/trace/trace_selftest.c index a7329b7902f8..e98fca60974f 100644 --- a/kernel/trace/trace_selftest.c +++ b/kernel/trace/trace_selftest.c @@ -1022,11 +1022,16 @@ trace_selftest_startup_nop(struct tracer *trace, struct trace_array *tr) #ifdef CONFIG_SCHED_TRACER static int trace_wakeup_test_thread(void *data) { - /* Make this a RT thread, doesn't need to be too high */ - static const struct sched_param param = { .sched_priority = 5 }; + /* Make this a -deadline thread */ + static const struct sched_attr attr = { + .sched_policy = SCHED_DEADLINE, + .sched_runtime = 100000ULL, + .sched_deadline = 10000000ULL, + .sched_period = 10000000ULL + }; struct completion *x = data; - sched_setscheduler(current, SCHED_FIFO, ¶m); + sched_setattr(current, &attr); /* Make it know we have a new prio */ complete(x); @@ -1040,8 +1045,8 @@ static int trace_wakeup_test_thread(void *data) /* we are awake, now wait to disappear */ while (!kthread_should_stop()) { /* - * This is an RT task, do short sleeps to let - * others run. + * This will likely be the system top priority + * task, do short sleeps to let others run. */ msleep(100); } @@ -1054,21 +1059,21 @@ trace_selftest_startup_wakeup(struct tracer *trace, struct trace_array *tr) { unsigned long save_max = tracing_max_latency; struct task_struct *p; - struct completion isrt; + struct completion is_ready; unsigned long count; int ret; - init_completion(&isrt); + init_completion(&is_ready); - /* create a high prio thread */ - p = kthread_run(trace_wakeup_test_thread, &isrt, "ftrace-test"); + /* create a -deadline thread */ + p = kthread_run(trace_wakeup_test_thread, &is_ready, "ftrace-test"); if (IS_ERR(p)) { printk(KERN_CONT "Failed to create ftrace wakeup test thread "); return -1; } - /* make sure the thread is running at an RT prio */ - wait_for_completion(&isrt); + /* make sure the thread is running at -deadline policy */ + wait_for_completion(&is_ready); /* start the tracing */ ret = tracer_init(trace, tr); @@ -1082,19 +1087,19 @@ trace_selftest_startup_wakeup(struct tracer *trace, struct trace_array *tr) while (p->on_rq) { /* - * Sleep to make sure the RT thread is asleep too. + * Sleep to make sure the -deadline thread is asleep too. * On virtual machines we can't rely on timings, * but we want to make sure this test still works. */ msleep(100); } - init_completion(&isrt); + init_completion(&is_ready); wake_up_process(p); /* Wait for the task to wake up */ - wait_for_completion(&isrt); + wait_for_completion(&is_ready); /* stop the tracing. */ tracing_stop(); diff --git a/kernel/trace/trace_stack.c b/kernel/trace/trace_stack.c index b20428c5efe2..e6be585cf06a 100644 --- a/kernel/trace/trace_stack.c +++ b/kernel/trace/trace_stack.c @@ -382,7 +382,7 @@ static const struct file_operations stack_trace_filter_fops = { .open = stack_trace_filter_open, .read = seq_read, .write = ftrace_filter_write, - .llseek = ftrace_filter_lseek, + .llseek = tracing_lseek, .release = ftrace_regex_release, }; diff --git a/kernel/trace/trace_syscalls.c b/kernel/trace/trace_syscalls.c index ea90eb5f6f17..759d5e004517 100644 --- a/kernel/trace/trace_syscalls.c +++ b/kernel/trace/trace_syscalls.c @@ -321,7 +321,7 @@ static void ftrace_syscall_enter(void *data, struct pt_regs *regs, long id) if (!ftrace_file) return; - if (test_bit(FTRACE_EVENT_FL_SOFT_DISABLED_BIT, &ftrace_file->flags)) + if (ftrace_trigger_soft_disabled(ftrace_file)) return; sys_data = syscall_nr_to_meta(syscall_nr); @@ -343,9 +343,8 @@ static void ftrace_syscall_enter(void *data, struct pt_regs *regs, long id) entry->nr = syscall_nr; syscall_get_arguments(current, regs, 0, sys_data->nb_args, entry->args); - if (!filter_check_discard(ftrace_file, entry, buffer, event)) - trace_current_buffer_unlock_commit(buffer, event, - irq_flags, pc); + event_trigger_unlock_commit(ftrace_file, buffer, event, entry, + irq_flags, pc); } static void ftrace_syscall_exit(void *data, struct pt_regs *regs, long ret) @@ -369,7 +368,7 @@ static void ftrace_syscall_exit(void *data, struct pt_regs *regs, long ret) if (!ftrace_file) return; - if (test_bit(FTRACE_EVENT_FL_SOFT_DISABLED_BIT, &ftrace_file->flags)) + if (ftrace_trigger_soft_disabled(ftrace_file)) return; sys_data = syscall_nr_to_meta(syscall_nr); @@ -390,9 +389,8 @@ static void ftrace_syscall_exit(void *data, struct pt_regs *regs, long ret) entry->nr = syscall_nr; entry->ret = syscall_get_return_value(current, regs); - if (!filter_check_discard(ftrace_file, entry, buffer, event)) - trace_current_buffer_unlock_commit(buffer, event, - irq_flags, pc); + event_trigger_unlock_commit(ftrace_file, buffer, event, entry, + irq_flags, pc); } static int reg_event_syscall_enter(struct ftrace_event_file *file, diff --git a/kernel/trace/trace_uprobe.c b/kernel/trace/trace_uprobe.c index b6dcc42ef7f5..79e52d93860b 100644 --- a/kernel/trace/trace_uprobe.c +++ b/kernel/trace/trace_uprobe.c @@ -51,22 +51,17 @@ struct trace_uprobe_filter { */ struct trace_uprobe { struct list_head list; - struct ftrace_event_class class; - struct ftrace_event_call call; struct trace_uprobe_filter filter; struct uprobe_consumer consumer; struct inode *inode; char *filename; unsigned long offset; unsigned long nhit; - unsigned int flags; /* For TP_FLAG_* */ - ssize_t size; /* trace entry size */ - unsigned int nr_args; - struct probe_arg args[]; + struct trace_probe tp; }; -#define SIZEOF_TRACE_UPROBE(n) \ - (offsetof(struct trace_uprobe, args) + \ +#define SIZEOF_TRACE_UPROBE(n) \ + (offsetof(struct trace_uprobe, tp.args) + \ (sizeof(struct probe_arg) * (n))) static int register_uprobe_event(struct trace_uprobe *tu); @@ -75,10 +70,151 @@ static int unregister_uprobe_event(struct trace_uprobe *tu); static DEFINE_MUTEX(uprobe_lock); static LIST_HEAD(uprobe_list); +struct uprobe_dispatch_data { + struct trace_uprobe *tu; + unsigned long bp_addr; +}; + static int uprobe_dispatcher(struct uprobe_consumer *con, struct pt_regs *regs); static int uretprobe_dispatcher(struct uprobe_consumer *con, unsigned long func, struct pt_regs *regs); +#ifdef CONFIG_STACK_GROWSUP +static unsigned long adjust_stack_addr(unsigned long addr, unsigned int n) +{ + return addr - (n * sizeof(long)); +} +#else +static unsigned long adjust_stack_addr(unsigned long addr, unsigned int n) +{ + return addr + (n * sizeof(long)); +} +#endif + +static unsigned long get_user_stack_nth(struct pt_regs *regs, unsigned int n) +{ + unsigned long ret; + unsigned long addr = user_stack_pointer(regs); + + addr = adjust_stack_addr(addr, n); + + if (copy_from_user(&ret, (void __force __user *) addr, sizeof(ret))) + return 0; + + return ret; +} + +/* + * Uprobes-specific fetch functions + */ +#define DEFINE_FETCH_stack(type) \ +static __kprobes void FETCH_FUNC_NAME(stack, type)(struct pt_regs *regs,\ + void *offset, void *dest) \ +{ \ + *(type *)dest = (type)get_user_stack_nth(regs, \ + ((unsigned long)offset)); \ +} +DEFINE_BASIC_FETCH_FUNCS(stack) +/* No string on the stack entry */ +#define fetch_stack_string NULL +#define fetch_stack_string_size NULL + +#define DEFINE_FETCH_memory(type) \ +static __kprobes void FETCH_FUNC_NAME(memory, type)(struct pt_regs *regs,\ + void *addr, void *dest) \ +{ \ + type retval; \ + void __user *vaddr = (void __force __user *) addr; \ + \ + if (copy_from_user(&retval, vaddr, sizeof(type))) \ + *(type *)dest = 0; \ + else \ + *(type *) dest = retval; \ +} +DEFINE_BASIC_FETCH_FUNCS(memory) +/* + * Fetch a null-terminated string. Caller MUST set *(u32 *)dest with max + * length and relative data location. + */ +static __kprobes void FETCH_FUNC_NAME(memory, string)(struct pt_regs *regs, + void *addr, void *dest) +{ + long ret; + u32 rloc = *(u32 *)dest; + int maxlen = get_rloc_len(rloc); + u8 *dst = get_rloc_data(dest); + void __user *src = (void __force __user *) addr; + + if (!maxlen) + return; + + ret = strncpy_from_user(dst, src, maxlen); + + if (ret < 0) { /* Failed to fetch string */ + ((u8 *)get_rloc_data(dest))[0] = '\0'; + *(u32 *)dest = make_data_rloc(0, get_rloc_offs(rloc)); + } else { + *(u32 *)dest = make_data_rloc(ret, get_rloc_offs(rloc)); + } +} + +static __kprobes void FETCH_FUNC_NAME(memory, string_size)(struct pt_regs *regs, + void *addr, void *dest) +{ + int len; + void __user *vaddr = (void __force __user *) addr; + + len = strnlen_user(vaddr, MAX_STRING_SIZE); + + if (len == 0 || len > MAX_STRING_SIZE) /* Failed to check length */ + *(u32 *)dest = 0; + else + *(u32 *)dest = len; +} + +static unsigned long translate_user_vaddr(void *file_offset) +{ + unsigned long base_addr; + struct uprobe_dispatch_data *udd; + + udd = (void *) current->utask->vaddr; + + base_addr = udd->bp_addr - udd->tu->offset; + return base_addr + (unsigned long)file_offset; +} + +#define DEFINE_FETCH_file_offset(type) \ +static __kprobes void FETCH_FUNC_NAME(file_offset, type)(struct pt_regs *regs,\ + void *offset, void *dest) \ +{ \ + void *vaddr = (void *)translate_user_vaddr(offset); \ + \ + FETCH_FUNC_NAME(memory, type)(regs, vaddr, dest); \ +} +DEFINE_BASIC_FETCH_FUNCS(file_offset) +DEFINE_FETCH_file_offset(string) +DEFINE_FETCH_file_offset(string_size) + +/* Fetch type information table */ +const struct fetch_type uprobes_fetch_type_table[] = { + /* Special types */ + [FETCH_TYPE_STRING] = __ASSIGN_FETCH_TYPE("string", string, string, + sizeof(u32), 1, "__data_loc char[]"), + [FETCH_TYPE_STRSIZE] = __ASSIGN_FETCH_TYPE("string_size", u32, + string_size, sizeof(u32), 0, "u32"), + /* Basic types */ + ASSIGN_FETCH_TYPE(u8, u8, 0), + ASSIGN_FETCH_TYPE(u16, u16, 0), + ASSIGN_FETCH_TYPE(u32, u32, 0), + ASSIGN_FETCH_TYPE(u64, u64, 0), + ASSIGN_FETCH_TYPE(s8, u8, 1), + ASSIGN_FETCH_TYPE(s16, u16, 1), + ASSIGN_FETCH_TYPE(s32, u32, 1), + ASSIGN_FETCH_TYPE(s64, u64, 1), + + ASSIGN_FETCH_TYPE_END +}; + static inline void init_trace_uprobe_filter(struct trace_uprobe_filter *filter) { rwlock_init(&filter->rwlock); @@ -114,13 +250,13 @@ alloc_trace_uprobe(const char *group, const char *event, int nargs, bool is_ret) if (!tu) return ERR_PTR(-ENOMEM); - tu->call.class = &tu->class; - tu->call.name = kstrdup(event, GFP_KERNEL); - if (!tu->call.name) + tu->tp.call.class = &tu->tp.class; + tu->tp.call.name = kstrdup(event, GFP_KERNEL); + if (!tu->tp.call.name) goto error; - tu->class.system = kstrdup(group, GFP_KERNEL); - if (!tu->class.system) + tu->tp.class.system = kstrdup(group, GFP_KERNEL); + if (!tu->tp.class.system) goto error; INIT_LIST_HEAD(&tu->list); @@ -128,11 +264,11 @@ alloc_trace_uprobe(const char *group, const char *event, int nargs, bool is_ret) if (is_ret) tu->consumer.ret_handler = uretprobe_dispatcher; init_trace_uprobe_filter(&tu->filter); - tu->call.flags |= TRACE_EVENT_FL_USE_CALL_FILTER; + tu->tp.call.flags |= TRACE_EVENT_FL_USE_CALL_FILTER; return tu; error: - kfree(tu->call.name); + kfree(tu->tp.call.name); kfree(tu); return ERR_PTR(-ENOMEM); @@ -142,12 +278,12 @@ static void free_trace_uprobe(struct trace_uprobe *tu) { int i; - for (i = 0; i < tu->nr_args; i++) - traceprobe_free_probe_arg(&tu->args[i]); + for (i = 0; i < tu->tp.nr_args; i++) + traceprobe_free_probe_arg(&tu->tp.args[i]); iput(tu->inode); - kfree(tu->call.class->system); - kfree(tu->call.name); + kfree(tu->tp.call.class->system); + kfree(tu->tp.call.name); kfree(tu->filename); kfree(tu); } @@ -157,8 +293,8 @@ static struct trace_uprobe *find_probe_event(const char *event, const char *grou struct trace_uprobe *tu; list_for_each_entry(tu, &uprobe_list, list) - if (strcmp(tu->call.name, event) == 0 && - strcmp(tu->call.class->system, group) == 0) + if (strcmp(tu->tp.call.name, event) == 0 && + strcmp(tu->tp.call.class->system, group) == 0) return tu; return NULL; @@ -181,16 +317,16 @@ static int unregister_trace_uprobe(struct trace_uprobe *tu) /* Register a trace_uprobe and probe_event */ static int register_trace_uprobe(struct trace_uprobe *tu) { - struct trace_uprobe *old_tp; + struct trace_uprobe *old_tu; int ret; mutex_lock(&uprobe_lock); /* register as an event */ - old_tp = find_probe_event(tu->call.name, tu->call.class->system); - if (old_tp) { + old_tu = find_probe_event(tu->tp.call.name, tu->tp.call.class->system); + if (old_tu) { /* delete old event */ - ret = unregister_trace_uprobe(old_tp); + ret = unregister_trace_uprobe(old_tu); if (ret) goto end; } @@ -211,7 +347,7 @@ end: /* * Argument syntax: - * - Add uprobe: p|r[:[GRP/]EVENT] PATH:SYMBOL [FETCHARGS] + * - Add uprobe: p|r[:[GRP/]EVENT] PATH:OFFSET [FETCHARGS] * * - Remove uprobe: -:[GRP/]EVENT */ @@ -360,34 +496,36 @@ static int create_trace_uprobe(int argc, char **argv) /* parse arguments */ ret = 0; for (i = 0; i < argc && i < MAX_TRACE_ARGS; i++) { + struct probe_arg *parg = &tu->tp.args[i]; + /* Increment count for freeing args in error case */ - tu->nr_args++; + tu->tp.nr_args++; /* Parse argument name */ arg = strchr(argv[i], '='); if (arg) { *arg++ = '\0'; - tu->args[i].name = kstrdup(argv[i], GFP_KERNEL); + parg->name = kstrdup(argv[i], GFP_KERNEL); } else { arg = argv[i]; /* If argument name is omitted, set "argN" */ snprintf(buf, MAX_EVENT_NAME_LEN, "arg%d", i + 1); - tu->args[i].name = kstrdup(buf, GFP_KERNEL); + parg->name = kstrdup(buf, GFP_KERNEL); } - if (!tu->args[i].name) { + if (!parg->name) { pr_info("Failed to allocate argument[%d] name.\n", i); ret = -ENOMEM; goto error; } - if (!is_good_name(tu->args[i].name)) { - pr_info("Invalid argument[%d] name: %s\n", i, tu->args[i].name); + if (!is_good_name(parg->name)) { + pr_info("Invalid argument[%d] name: %s\n", i, parg->name); ret = -EINVAL; goto error; } - if (traceprobe_conflict_field_name(tu->args[i].name, tu->args, i)) { + if (traceprobe_conflict_field_name(parg->name, tu->tp.args, i)) { pr_info("Argument[%d] name '%s' conflicts with " "another field.\n", i, argv[i]); ret = -EINVAL; @@ -395,7 +533,8 @@ static int create_trace_uprobe(int argc, char **argv) } /* Parse fetch argument */ - ret = traceprobe_parse_probe_arg(arg, &tu->size, &tu->args[i], false, false); + ret = traceprobe_parse_probe_arg(arg, &tu->tp.size, parg, + is_return, false); if (ret) { pr_info("Parse error at argument[%d]. (%d)\n", i, ret); goto error; @@ -459,11 +598,11 @@ static int probes_seq_show(struct seq_file *m, void *v) char c = is_ret_probe(tu) ? 'r' : 'p'; int i; - seq_printf(m, "%c:%s/%s", c, tu->call.class->system, tu->call.name); + seq_printf(m, "%c:%s/%s", c, tu->tp.call.class->system, tu->tp.call.name); seq_printf(m, " %s:0x%p", tu->filename, (void *)tu->offset); - for (i = 0; i < tu->nr_args; i++) - seq_printf(m, " %s=%s", tu->args[i].name, tu->args[i].comm); + for (i = 0; i < tu->tp.nr_args; i++) + seq_printf(m, " %s=%s", tu->tp.args[i].name, tu->tp.args[i].comm); seq_printf(m, "\n"); return 0; @@ -509,7 +648,7 @@ static int probes_profile_seq_show(struct seq_file *m, void *v) { struct trace_uprobe *tu = v; - seq_printf(m, " %s %-44s %15lu\n", tu->filename, tu->call.name, tu->nhit); + seq_printf(m, " %s %-44s %15lu\n", tu->filename, tu->tp.call.name, tu->nhit); return 0; } @@ -533,21 +672,117 @@ static const struct file_operations uprobe_profile_ops = { .release = seq_release, }; +struct uprobe_cpu_buffer { + struct mutex mutex; + void *buf; +}; +static struct uprobe_cpu_buffer __percpu *uprobe_cpu_buffer; +static int uprobe_buffer_refcnt; + +static int uprobe_buffer_init(void) +{ + int cpu, err_cpu; + + uprobe_cpu_buffer = alloc_percpu(struct uprobe_cpu_buffer); + if (uprobe_cpu_buffer == NULL) + return -ENOMEM; + + for_each_possible_cpu(cpu) { + struct page *p = alloc_pages_node(cpu_to_node(cpu), + GFP_KERNEL, 0); + if (p == NULL) { + err_cpu = cpu; + goto err; + } + per_cpu_ptr(uprobe_cpu_buffer, cpu)->buf = page_address(p); + mutex_init(&per_cpu_ptr(uprobe_cpu_buffer, cpu)->mutex); + } + + return 0; + +err: + for_each_possible_cpu(cpu) { + if (cpu == err_cpu) + break; + free_page((unsigned long)per_cpu_ptr(uprobe_cpu_buffer, cpu)->buf); + } + + free_percpu(uprobe_cpu_buffer); + return -ENOMEM; +} + +static int uprobe_buffer_enable(void) +{ + int ret = 0; + + BUG_ON(!mutex_is_locked(&event_mutex)); + + if (uprobe_buffer_refcnt++ == 0) { + ret = uprobe_buffer_init(); + if (ret < 0) + uprobe_buffer_refcnt--; + } + + return ret; +} + +static void uprobe_buffer_disable(void) +{ + BUG_ON(!mutex_is_locked(&event_mutex)); + + if (--uprobe_buffer_refcnt == 0) { + free_percpu(uprobe_cpu_buffer); + uprobe_cpu_buffer = NULL; + } +} + +static struct uprobe_cpu_buffer *uprobe_buffer_get(void) +{ + struct uprobe_cpu_buffer *ucb; + int cpu; + + cpu = raw_smp_processor_id(); + ucb = per_cpu_ptr(uprobe_cpu_buffer, cpu); + + /* + * Use per-cpu buffers for fastest access, but we might migrate + * so the mutex makes sure we have sole access to it. + */ + mutex_lock(&ucb->mutex); + + return ucb; +} + +static void uprobe_buffer_put(struct uprobe_cpu_buffer *ucb) +{ + mutex_unlock(&ucb->mutex); +} + static void uprobe_trace_print(struct trace_uprobe *tu, unsigned long func, struct pt_regs *regs) { struct uprobe_trace_entry_head *entry; struct ring_buffer_event *event; struct ring_buffer *buffer; + struct uprobe_cpu_buffer *ucb; void *data; - int size, i; - struct ftrace_event_call *call = &tu->call; + int size, dsize, esize; + struct ftrace_event_call *call = &tu->tp.call; + + dsize = __get_data_size(&tu->tp, regs); + esize = SIZEOF_TRACE_ENTRY(is_ret_probe(tu)); - size = SIZEOF_TRACE_ENTRY(is_ret_probe(tu)); + if (WARN_ON_ONCE(!uprobe_cpu_buffer || tu->tp.size + dsize > PAGE_SIZE)) + return; + + ucb = uprobe_buffer_get(); + store_trace_args(esize, &tu->tp, regs, ucb->buf, dsize); + + size = esize + tu->tp.size + dsize; event = trace_current_buffer_lock_reserve(&buffer, call->event.type, - size + tu->size, 0, 0); + size, 0, 0); if (!event) - return; + goto out; entry = ring_buffer_event_data(event); if (is_ret_probe(tu)) { @@ -559,11 +794,13 @@ static void uprobe_trace_print(struct trace_uprobe *tu, data = DATAOF_TRACE_ENTRY(entry, false); } - for (i = 0; i < tu->nr_args; i++) - call_fetch(&tu->args[i].fetch, regs, data + tu->args[i].offset); + memcpy(data, ucb->buf, tu->tp.size + dsize); if (!call_filter_check_discard(call, entry, buffer, event)) trace_buffer_unlock_commit(buffer, event, 0, 0); + +out: + uprobe_buffer_put(ucb); } /* uprobe handler */ @@ -591,23 +828,24 @@ print_uprobe_event(struct trace_iterator *iter, int flags, struct trace_event *e int i; entry = (struct uprobe_trace_entry_head *)iter->ent; - tu = container_of(event, struct trace_uprobe, call.event); + tu = container_of(event, struct trace_uprobe, tp.call.event); if (is_ret_probe(tu)) { - if (!trace_seq_printf(s, "%s: (0x%lx <- 0x%lx)", tu->call.name, + if (!trace_seq_printf(s, "%s: (0x%lx <- 0x%lx)", tu->tp.call.name, entry->vaddr[1], entry->vaddr[0])) goto partial; data = DATAOF_TRACE_ENTRY(entry, true); } else { - if (!trace_seq_printf(s, "%s: (0x%lx)", tu->call.name, + if (!trace_seq_printf(s, "%s: (0x%lx)", tu->tp.call.name, entry->vaddr[0])) goto partial; data = DATAOF_TRACE_ENTRY(entry, false); } - for (i = 0; i < tu->nr_args; i++) { - if (!tu->args[i].type->print(s, tu->args[i].name, - data + tu->args[i].offset, entry)) + for (i = 0; i < tu->tp.nr_args; i++) { + struct probe_arg *parg = &tu->tp.args[i]; + + if (!parg->type->print(s, parg->name, data + parg->offset, entry)) goto partial; } @@ -618,11 +856,6 @@ partial: return TRACE_TYPE_PARTIAL_LINE; } -static inline bool is_trace_uprobe_enabled(struct trace_uprobe *tu) -{ - return tu->flags & (TP_FLAG_TRACE | TP_FLAG_PROFILE); -} - typedef bool (*filter_func_t)(struct uprobe_consumer *self, enum uprobe_filter_ctx ctx, struct mm_struct *mm); @@ -632,29 +865,35 @@ probe_event_enable(struct trace_uprobe *tu, int flag, filter_func_t filter) { int ret = 0; - if (is_trace_uprobe_enabled(tu)) + if (trace_probe_is_enabled(&tu->tp)) return -EINTR; + ret = uprobe_buffer_enable(); + if (ret < 0) + return ret; + WARN_ON(!uprobe_filter_is_empty(&tu->filter)); - tu->flags |= flag; + tu->tp.flags |= flag; tu->consumer.filter = filter; ret = uprobe_register(tu->inode, tu->offset, &tu->consumer); if (ret) - tu->flags &= ~flag; + tu->tp.flags &= ~flag; return ret; } static void probe_event_disable(struct trace_uprobe *tu, int flag) { - if (!is_trace_uprobe_enabled(tu)) + if (!trace_probe_is_enabled(&tu->tp)) return; WARN_ON(!uprobe_filter_is_empty(&tu->filter)); uprobe_unregister(tu->inode, tu->offset, &tu->consumer); - tu->flags &= ~flag; + tu->tp.flags &= ~flag; + + uprobe_buffer_disable(); } static int uprobe_event_define_fields(struct ftrace_event_call *event_call) @@ -672,12 +911,12 @@ static int uprobe_event_define_fields(struct ftrace_event_call *event_call) size = SIZEOF_TRACE_ENTRY(false); } /* Set argument names as fields */ - for (i = 0; i < tu->nr_args; i++) { - ret = trace_define_field(event_call, tu->args[i].type->fmttype, - tu->args[i].name, - size + tu->args[i].offset, - tu->args[i].type->size, - tu->args[i].type->is_signed, + for (i = 0; i < tu->tp.nr_args; i++) { + struct probe_arg *parg = &tu->tp.args[i]; + + ret = trace_define_field(event_call, parg->type->fmttype, + parg->name, size + parg->offset, + parg->type->size, parg->type->is_signed, FILTER_OTHER); if (ret) @@ -686,59 +925,6 @@ static int uprobe_event_define_fields(struct ftrace_event_call *event_call) return 0; } -#define LEN_OR_ZERO (len ? len - pos : 0) -static int __set_print_fmt(struct trace_uprobe *tu, char *buf, int len) -{ - const char *fmt, *arg; - int i; - int pos = 0; - - if (is_ret_probe(tu)) { - fmt = "(%lx <- %lx)"; - arg = "REC->" FIELD_STRING_FUNC ", REC->" FIELD_STRING_RETIP; - } else { - fmt = "(%lx)"; - arg = "REC->" FIELD_STRING_IP; - } - - /* When len=0, we just calculate the needed length */ - - pos += snprintf(buf + pos, LEN_OR_ZERO, "\"%s", fmt); - - for (i = 0; i < tu->nr_args; i++) { - pos += snprintf(buf + pos, LEN_OR_ZERO, " %s=%s", - tu->args[i].name, tu->args[i].type->fmt); - } - - pos += snprintf(buf + pos, LEN_OR_ZERO, "\", %s", arg); - - for (i = 0; i < tu->nr_args; i++) { - pos += snprintf(buf + pos, LEN_OR_ZERO, ", REC->%s", - tu->args[i].name); - } - - return pos; /* return the length of print_fmt */ -} -#undef LEN_OR_ZERO - -static int set_print_fmt(struct trace_uprobe *tu) -{ - char *print_fmt; - int len; - - /* First: called with 0 length to calculate the needed length */ - len = __set_print_fmt(tu, NULL, 0); - print_fmt = kmalloc(len + 1, GFP_KERNEL); - if (!print_fmt) - return -ENOMEM; - - /* Second: actually write the @print_fmt */ - __set_print_fmt(tu, print_fmt, len + 1); - tu->call.print_fmt = print_fmt; - - return 0; -} - #ifdef CONFIG_PERF_EVENTS static bool __uprobe_perf_filter(struct trace_uprobe_filter *filter, struct mm_struct *mm) @@ -831,14 +1017,27 @@ static bool uprobe_perf_filter(struct uprobe_consumer *uc, static void uprobe_perf_print(struct trace_uprobe *tu, unsigned long func, struct pt_regs *regs) { - struct ftrace_event_call *call = &tu->call; + struct ftrace_event_call *call = &tu->tp.call; struct uprobe_trace_entry_head *entry; struct hlist_head *head; + struct uprobe_cpu_buffer *ucb; void *data; - int size, rctx, i; + int size, dsize, esize; + int rctx; - size = SIZEOF_TRACE_ENTRY(is_ret_probe(tu)); - size = ALIGN(size + tu->size + sizeof(u32), sizeof(u64)) - sizeof(u32); + dsize = __get_data_size(&tu->tp, regs); + esize = SIZEOF_TRACE_ENTRY(is_ret_probe(tu)); + + if (WARN_ON_ONCE(!uprobe_cpu_buffer)) + return; + + size = esize + tu->tp.size + dsize; + size = ALIGN(size + sizeof(u32), sizeof(u64)) - sizeof(u32); + if (WARN_ONCE(size > PERF_MAX_TRACE_SIZE, "profile buffer not large enough")) + return; + + ucb = uprobe_buffer_get(); + store_trace_args(esize, &tu->tp, regs, ucb->buf, dsize); preempt_disable(); head = this_cpu_ptr(call->perf_events); @@ -858,12 +1057,18 @@ static void uprobe_perf_print(struct trace_uprobe *tu, data = DATAOF_TRACE_ENTRY(entry, false); } - for (i = 0; i < tu->nr_args; i++) - call_fetch(&tu->args[i].fetch, regs, data + tu->args[i].offset); + memcpy(data, ucb->buf, tu->tp.size + dsize); + + if (size - esize > tu->tp.size + dsize) { + int len = tu->tp.size + dsize; + + memset(data + len, 0, size - esize - len); + } perf_trace_buf_submit(entry, size, rctx, 0, 1, regs, head, NULL); out: preempt_enable(); + uprobe_buffer_put(ucb); } /* uprobe profile handler */ @@ -921,16 +1126,22 @@ int trace_uprobe_register(struct ftrace_event_call *event, enum trace_reg type, static int uprobe_dispatcher(struct uprobe_consumer *con, struct pt_regs *regs) { struct trace_uprobe *tu; + struct uprobe_dispatch_data udd; int ret = 0; tu = container_of(con, struct trace_uprobe, consumer); tu->nhit++; - if (tu->flags & TP_FLAG_TRACE) + udd.tu = tu; + udd.bp_addr = instruction_pointer(regs); + + current->utask->vaddr = (unsigned long) &udd; + + if (tu->tp.flags & TP_FLAG_TRACE) ret |= uprobe_trace_func(tu, regs); #ifdef CONFIG_PERF_EVENTS - if (tu->flags & TP_FLAG_PROFILE) + if (tu->tp.flags & TP_FLAG_PROFILE) ret |= uprobe_perf_func(tu, regs); #endif return ret; @@ -940,14 +1151,20 @@ static int uretprobe_dispatcher(struct uprobe_consumer *con, unsigned long func, struct pt_regs *regs) { struct trace_uprobe *tu; + struct uprobe_dispatch_data udd; tu = container_of(con, struct trace_uprobe, consumer); - if (tu->flags & TP_FLAG_TRACE) + udd.tu = tu; + udd.bp_addr = func; + + current->utask->vaddr = (unsigned long) &udd; + + if (tu->tp.flags & TP_FLAG_TRACE) uretprobe_trace_func(tu, func, regs); #ifdef CONFIG_PERF_EVENTS - if (tu->flags & TP_FLAG_PROFILE) + if (tu->tp.flags & TP_FLAG_PROFILE) uretprobe_perf_func(tu, func, regs); #endif return 0; @@ -959,7 +1176,7 @@ static struct trace_event_functions uprobe_funcs = { static int register_uprobe_event(struct trace_uprobe *tu) { - struct ftrace_event_call *call = &tu->call; + struct ftrace_event_call *call = &tu->tp.call; int ret; /* Initialize ftrace_event_call */ @@ -967,7 +1184,7 @@ static int register_uprobe_event(struct trace_uprobe *tu) call->event.funcs = &uprobe_funcs; call->class->define_fields = uprobe_event_define_fields; - if (set_print_fmt(tu) < 0) + if (set_print_fmt(&tu->tp, is_ret_probe(tu)) < 0) return -ENOMEM; ret = register_ftrace_event(&call->event); @@ -994,11 +1211,11 @@ static int unregister_uprobe_event(struct trace_uprobe *tu) int ret; /* tu->event is unregistered in trace_remove_event_call() */ - ret = trace_remove_event_call(&tu->call); + ret = trace_remove_event_call(&tu->tp.call); if (ret) return ret; - kfree(tu->call.print_fmt); - tu->call.print_fmt = NULL; + kfree(tu->tp.call.print_fmt); + tu->tp.call.print_fmt = NULL; return 0; } diff --git a/kernel/workqueue.c b/kernel/workqueue.c index b010eac595d2..82ef9f3b7473 100644 --- a/kernel/workqueue.c +++ b/kernel/workqueue.c @@ -4789,6 +4789,7 @@ static int workqueue_cpu_down_callback(struct notifier_block *nfb, /* wait for per-cpu unbinding to finish */ flush_work(&unbind_work); + destroy_work_on_stack(&unbind_work); break; } return NOTIFY_OK; @@ -4828,6 +4829,7 @@ long work_on_cpu(int cpu, long (*fn)(void *), void *arg) INIT_WORK_ONSTACK(&wfc.work, work_for_cpu_fn); schedule_work_on(cpu, &wfc.work); flush_work(&wfc.work); + destroy_work_on_stack(&wfc.work); return wfc.ret; } EXPORT_SYMBOL_GPL(work_on_cpu); |