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path: root/drivers/staging/lustre/lustre/llite/statahead.c
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Diffstat (limited to 'drivers/staging/lustre/lustre/llite/statahead.c')
-rw-r--r--drivers/staging/lustre/lustre/llite/statahead.c1439
1 files changed, 690 insertions, 749 deletions
diff --git a/drivers/staging/lustre/lustre/llite/statahead.c b/drivers/staging/lustre/lustre/llite/statahead.c
index c1cb6b19e724..0677513476ec 100644
--- a/drivers/staging/lustre/lustre/llite/statahead.c
+++ b/drivers/staging/lustre/lustre/llite/statahead.c
@@ -39,7 +39,6 @@
#define DEBUG_SUBSYSTEM S_LLITE
#include "../include/obd_support.h"
-#include "../include/lustre_lite.h"
#include "../include/lustre_dlm.h"
#include "llite_internal.h"
@@ -50,24 +49,26 @@ enum se_stat {
SA_ENTRY_INIT = 0, /** init entry */
SA_ENTRY_SUCC = 1, /** stat succeed */
SA_ENTRY_INVA = 2, /** invalid entry */
- SA_ENTRY_DEST = 3, /** entry to be destroyed */
};
-struct ll_sa_entry {
- /* link into sai->sai_entries */
- struct list_head se_link;
- /* link into sai->sai_entries_{received,stated} */
+/*
+ * sa_entry is not refcounted: statahead thread allocates it and do async stat,
+ * and in async stat callback ll_statahead_interpret() will add it into
+ * sai_interim_entries, later statahead thread will call sa_handle_callback() to
+ * instantiate entry and move it into sai_entries, and then only scanner process
+ * can access and free it.
+ */
+struct sa_entry {
+ /* link into sai_interim_entries or sai_entries */
struct list_head se_list;
/* link into sai hash table locally */
struct list_head se_hash;
- /* entry reference count */
- atomic_t se_refcount;
/* entry index in the sai */
__u64 se_index;
/* low layer ldlm lock handle */
__u64 se_handle;
/* entry status */
- enum se_stat se_stat;
+ enum se_stat se_state;
/* entry size, contains name */
int se_size;
/* pointer to async getattr enqueue info */
@@ -83,27 +84,24 @@ struct ll_sa_entry {
static unsigned int sai_generation;
static DEFINE_SPINLOCK(sai_generation_lock);
-/*
- * The entry only can be released by the caller, it is necessary to hold lock.
- */
-static inline int ll_sa_entry_stated(struct ll_sa_entry *entry)
+/* sa_entry is ready to use */
+static inline int sa_ready(struct sa_entry *entry)
{
smp_rmb();
- return (entry->se_stat != SA_ENTRY_INIT);
+ return (entry->se_state != SA_ENTRY_INIT);
}
-static inline int ll_sa_entry_hash(int val)
+/* hash value to put in sai_cache */
+static inline int sa_hash(int val)
{
return val & LL_SA_CACHE_MASK;
}
-/*
- * Insert entry to hash SA table.
- */
+/* hash entry into sai_cache */
static inline void
-ll_sa_entry_enhash(struct ll_statahead_info *sai, struct ll_sa_entry *entry)
+sa_rehash(struct ll_statahead_info *sai, struct sa_entry *entry)
{
- int i = ll_sa_entry_hash(entry->se_qstr.hash);
+ int i = sa_hash(entry->se_qstr.hash);
spin_lock(&sai->sai_cache_lock[i]);
list_add_tail(&entry->se_hash, &sai->sai_cache[i]);
@@ -114,9 +112,9 @@ ll_sa_entry_enhash(struct ll_statahead_info *sai, struct ll_sa_entry *entry)
* Remove entry from SA table.
*/
static inline void
-ll_sa_entry_unhash(struct ll_statahead_info *sai, struct ll_sa_entry *entry)
+sa_unhash(struct ll_statahead_info *sai, struct sa_entry *entry)
{
- int i = ll_sa_entry_hash(entry->se_qstr.hash);
+ int i = sa_hash(entry->se_qstr.hash);
spin_lock(&sai->sai_cache_lock[i]);
list_del_init(&entry->se_hash);
@@ -129,19 +127,21 @@ static inline int agl_should_run(struct ll_statahead_info *sai,
return (inode && S_ISREG(inode->i_mode) && sai->sai_agl_valid);
}
+/* statahead window is full */
static inline int sa_sent_full(struct ll_statahead_info *sai)
{
return atomic_read(&sai->sai_cache_count) >= sai->sai_max;
}
-static inline int sa_received_empty(struct ll_statahead_info *sai)
+/* got async stat replies */
+static inline int sa_has_callback(struct ll_statahead_info *sai)
{
- return list_empty(&sai->sai_entries_received);
+ return !list_empty(&sai->sai_interim_entries);
}
static inline int agl_list_empty(struct ll_statahead_info *sai)
{
- return list_empty(&sai->sai_entries_agl);
+ return list_empty(&sai->sai_agls);
}
/**
@@ -157,7 +157,7 @@ static inline int sa_low_hit(struct ll_statahead_info *sai)
}
/*
- * If the given index is behind of statahead window more than
+ * if the given index is behind of statahead window more than
* SA_OMITTED_ENTRY_MAX, then it is old.
*/
static inline int is_omitted_entry(struct ll_statahead_info *sai, __u64 index)
@@ -166,20 +166,17 @@ static inline int is_omitted_entry(struct ll_statahead_info *sai, __u64 index)
sai->sai_index);
}
-/*
- * Insert it into sai_entries tail when init.
- */
-static struct ll_sa_entry *
-ll_sa_entry_alloc(struct dentry *parent,
- struct ll_statahead_info *sai, __u64 index,
- const char *name, int len)
+/* allocate sa_entry and hash it to allow scanner process to find it */
+static struct sa_entry *
+sa_alloc(struct dentry *parent, struct ll_statahead_info *sai, __u64 index,
+ const char *name, int len)
{
struct ll_inode_info *lli;
- struct ll_sa_entry *entry;
+ struct sa_entry *entry;
int entry_size;
char *dname;
- entry_size = sizeof(struct ll_sa_entry) + (len & ~3) + 4;
+ entry_size = sizeof(struct sa_entry) + (len & ~3) + 4;
entry = kzalloc(entry_size, GFP_NOFS);
if (unlikely(!entry))
return ERR_PTR(-ENOMEM);
@@ -188,34 +185,9 @@ ll_sa_entry_alloc(struct dentry *parent,
len, name, entry, index);
entry->se_index = index;
-
- /*
- * Statahead entry reference rules:
- *
- * 1) When statahead entry is initialized, its reference is set as 2.
- * One reference is used by the directory scanner. When the scanner
- * searches the statahead cache for the given name, it can perform
- * lockless hash lookup (only the scanner can remove entry from hash
- * list), and once found, it needn't to call "atomic_inc()" for the
- * entry reference. So the performance is improved. After using the
- * statahead entry, the scanner will call "atomic_dec()" to drop the
- * reference held when initialization. If it is the last reference,
- * the statahead entry will be freed.
- *
- * 2) All other threads, including statahead thread and ptlrpcd thread,
- * when they process the statahead entry, the reference for target
- * should be held to guarantee the entry will not be released by the
- * directory scanner. After processing the entry, these threads will
- * drop the entry reference. If it is the last reference, the entry
- * will be freed.
- *
- * The second reference when initializes the statahead entry is used
- * by the statahead thread, following the rule 2).
- */
- atomic_set(&entry->se_refcount, 2);
- entry->se_stat = SA_ENTRY_INIT;
+ entry->se_state = SA_ENTRY_INIT;
entry->se_size = entry_size;
- dname = (char *)entry + sizeof(struct ll_sa_entry);
+ dname = (char *)entry + sizeof(struct sa_entry);
memcpy(dname, name, len);
dname[len] = 0;
@@ -223,11 +195,10 @@ ll_sa_entry_alloc(struct dentry *parent,
entry->se_qstr.len = len;
entry->se_qstr.name = dname;
- lli = ll_i2info(sai->sai_inode);
+ lli = ll_i2info(sai->sai_dentry->d_inode);
spin_lock(&lli->lli_sa_lock);
- list_add_tail(&entry->se_link, &sai->sai_entries);
INIT_LIST_HEAD(&entry->se_list);
- ll_sa_entry_enhash(sai, entry);
+ sa_rehash(sai, entry);
spin_unlock(&lli->lli_sa_lock);
atomic_inc(&sai->sai_cache_count);
@@ -235,18 +206,29 @@ ll_sa_entry_alloc(struct dentry *parent,
return entry;
}
+/* free sa_entry, which should have been unhashed and not in any list */
+static void sa_free(struct ll_statahead_info *sai, struct sa_entry *entry)
+{
+ CDEBUG(D_READA, "free sa entry %.*s(%p) index %llu\n",
+ entry->se_qstr.len, entry->se_qstr.name, entry,
+ entry->se_index);
+
+ LASSERT(list_empty(&entry->se_list));
+ LASSERT(list_empty(&entry->se_hash));
+
+ kfree(entry);
+ atomic_dec(&sai->sai_cache_count);
+}
+
/*
- * Used by the directory scanner to search entry with name.
- *
- * Only the caller can remove the entry from hash, so it is unnecessary to hold
- * hash lock. It is caller's duty to release the init refcount on the entry, so
- * it is also unnecessary to increase refcount on the entry.
+ * find sa_entry by name, used by directory scanner, lock is not needed because
+ * only scanner can remove the entry from cache.
*/
-static struct ll_sa_entry *
-ll_sa_entry_get_byname(struct ll_statahead_info *sai, const struct qstr *qstr)
+static struct sa_entry *
+sa_get(struct ll_statahead_info *sai, const struct qstr *qstr)
{
- struct ll_sa_entry *entry;
- int i = ll_sa_entry_hash(qstr->hash);
+ struct sa_entry *entry;
+ int i = sa_hash(qstr->hash);
list_for_each_entry(entry, &sai->sai_cache[i], se_hash) {
if (entry->se_qstr.hash == qstr->hash &&
@@ -257,164 +239,126 @@ ll_sa_entry_get_byname(struct ll_statahead_info *sai, const struct qstr *qstr)
return NULL;
}
-/*
- * Used by the async getattr request callback to find entry with index.
- *
- * Inside lli_sa_lock to prevent others to change the list during the search.
- * It needs to increase entry refcount before returning to guarantee that the
- * entry cannot be freed by others.
- */
-static struct ll_sa_entry *
-ll_sa_entry_get_byindex(struct ll_statahead_info *sai, __u64 index)
-{
- struct ll_sa_entry *entry;
-
- list_for_each_entry(entry, &sai->sai_entries, se_link) {
- if (entry->se_index == index) {
- LASSERT(atomic_read(&entry->se_refcount) > 0);
- atomic_inc(&entry->se_refcount);
- return entry;
- }
- if (entry->se_index > index)
- break;
- }
- return NULL;
-}
-
-static void ll_sa_entry_cleanup(struct ll_statahead_info *sai,
- struct ll_sa_entry *entry)
-{
- struct md_enqueue_info *minfo = entry->se_minfo;
- struct ptlrpc_request *req = entry->se_req;
-
- if (minfo) {
- entry->se_minfo = NULL;
- ll_intent_release(&minfo->mi_it);
- iput(minfo->mi_dir);
- kfree(minfo);
- }
-
- if (req) {
- entry->se_req = NULL;
- ptlrpc_req_finished(req);
- }
-}
-
-static void ll_sa_entry_put(struct ll_statahead_info *sai,
- struct ll_sa_entry *entry)
-{
- if (atomic_dec_and_test(&entry->se_refcount)) {
- CDEBUG(D_READA, "free sa entry %.*s(%p) index %llu\n",
- entry->se_qstr.len, entry->se_qstr.name, entry,
- entry->se_index);
-
- LASSERT(list_empty(&entry->se_link));
- LASSERT(list_empty(&entry->se_list));
- LASSERT(list_empty(&entry->se_hash));
-
- ll_sa_entry_cleanup(sai, entry);
- iput(entry->se_inode);
-
- kfree(entry);
- atomic_dec(&sai->sai_cache_count);
- }
-}
-
+/* unhash and unlink sa_entry, and then free it */
static inline void
-do_sa_entry_fini(struct ll_statahead_info *sai, struct ll_sa_entry *entry)
+sa_kill(struct ll_statahead_info *sai, struct sa_entry *entry)
{
- struct ll_inode_info *lli = ll_i2info(sai->sai_inode);
+ struct ll_inode_info *lli = ll_i2info(sai->sai_dentry->d_inode);
LASSERT(!list_empty(&entry->se_hash));
- LASSERT(!list_empty(&entry->se_link));
+ LASSERT(!list_empty(&entry->se_list));
+ LASSERT(sa_ready(entry));
- ll_sa_entry_unhash(sai, entry);
+ sa_unhash(sai, entry);
spin_lock(&lli->lli_sa_lock);
- entry->se_stat = SA_ENTRY_DEST;
- list_del_init(&entry->se_link);
- if (likely(!list_empty(&entry->se_list)))
- list_del_init(&entry->se_list);
+ list_del_init(&entry->se_list);
spin_unlock(&lli->lli_sa_lock);
- ll_sa_entry_put(sai, entry);
+ if (entry->se_inode)
+ iput(entry->se_inode);
+
+ sa_free(sai, entry);
}
-/*
- * Delete it from sai_entries_stated list when fini.
- */
+/* called by scanner after use, sa_entry will be killed */
static void
-ll_sa_entry_fini(struct ll_statahead_info *sai, struct ll_sa_entry *entry)
+sa_put(struct ll_statahead_info *sai, struct sa_entry *entry)
{
- struct ll_sa_entry *pos, *next;
+ struct sa_entry *tmp, *next;
+
+ if (entry && entry->se_state == SA_ENTRY_SUCC) {
+ struct ll_sb_info *sbi = ll_i2sbi(sai->sai_dentry->d_inode);
+
+ sai->sai_hit++;
+ sai->sai_consecutive_miss = 0;
+ sai->sai_max = min(2 * sai->sai_max, sbi->ll_sa_max);
+ } else {
+ sai->sai_miss++;
+ sai->sai_consecutive_miss++;
+ }
if (entry)
- do_sa_entry_fini(sai, entry);
+ sa_kill(sai, entry);
- /* drop old entry, only 'scanner' process does this, no need to lock */
- list_for_each_entry_safe(pos, next, &sai->sai_entries, se_link) {
- if (!is_omitted_entry(sai, pos->se_index))
+ /*
+ * kill old completed entries, only scanner process does this, no need
+ * to lock
+ */
+ list_for_each_entry_safe(tmp, next, &sai->sai_entries, se_list) {
+ if (!is_omitted_entry(sai, tmp->se_index))
break;
- do_sa_entry_fini(sai, pos);
+ sa_kill(sai, tmp);
}
+
+ wake_up(&sai->sai_thread.t_ctl_waitq);
}
/*
- * Inside lli_sa_lock.
+ * update state and sort add entry to sai_entries by index, return true if
+ * scanner is waiting on this entry.
*/
-static void
-do_sa_entry_to_stated(struct ll_statahead_info *sai,
- struct ll_sa_entry *entry, enum se_stat stat)
+static bool
+__sa_make_ready(struct ll_statahead_info *sai, struct sa_entry *entry, int ret)
{
- struct ll_sa_entry *se;
- struct list_head *pos = &sai->sai_entries_stated;
+ struct list_head *pos = &sai->sai_entries;
+ __u64 index = entry->se_index;
+ struct sa_entry *se;
- if (!list_empty(&entry->se_list))
- list_del_init(&entry->se_list);
+ LASSERT(!sa_ready(entry));
+ LASSERT(list_empty(&entry->se_list));
- list_for_each_entry_reverse(se, &sai->sai_entries_stated, se_list) {
+ list_for_each_entry_reverse(se, &sai->sai_entries, se_list) {
if (se->se_index < entry->se_index) {
pos = &se->se_list;
break;
}
}
-
list_add(&entry->se_list, pos);
- entry->se_stat = stat;
+ entry->se_state = ret < 0 ? SA_ENTRY_INVA : SA_ENTRY_SUCC;
+
+ return (index == sai->sai_index_wait);
}
/*
- * Move entry to sai_entries_stated and sort with the index.
- * \retval 1 -- entry to be destroyed.
- * \retval 0 -- entry is inserted into stated list.
+ * release resources used in async stat RPC, update entry state and wakeup if
+ * scanner process it waiting on this entry.
*/
-static int
-ll_sa_entry_to_stated(struct ll_statahead_info *sai,
- struct ll_sa_entry *entry, enum se_stat stat)
+static void
+sa_make_ready(struct ll_statahead_info *sai, struct sa_entry *entry, int ret)
{
- struct ll_inode_info *lli = ll_i2info(sai->sai_inode);
- int ret = 1;
+ struct ll_inode_info *lli = ll_i2info(sai->sai_dentry->d_inode);
+ struct md_enqueue_info *minfo = entry->se_minfo;
+ struct ptlrpc_request *req = entry->se_req;
+ bool wakeup;
+
+ /* release resources used in RPC */
+ if (minfo) {
+ entry->se_minfo = NULL;
+ ll_intent_release(&minfo->mi_it);
+ iput(minfo->mi_dir);
+ kfree(minfo);
+ }
- ll_sa_entry_cleanup(sai, entry);
+ if (req) {
+ entry->se_req = NULL;
+ ptlrpc_req_finished(req);
+ }
spin_lock(&lli->lli_sa_lock);
- if (likely(entry->se_stat != SA_ENTRY_DEST)) {
- do_sa_entry_to_stated(sai, entry, stat);
- ret = 0;
- }
+ wakeup = __sa_make_ready(sai, entry, ret);
spin_unlock(&lli->lli_sa_lock);
- return ret;
+ if (wakeup)
+ wake_up(&sai->sai_waitq);
}
-/*
- * Insert inode into the list of sai_entries_agl.
- */
+/* Insert inode into the list of sai_agls. */
static void ll_agl_add(struct ll_statahead_info *sai,
struct inode *inode, int index)
{
struct ll_inode_info *child = ll_i2info(inode);
- struct ll_inode_info *parent = ll_i2info(sai->sai_inode);
+ struct ll_inode_info *parent = ll_i2info(sai->sai_dentry->d_inode);
int added = 0;
spin_lock(&child->lli_agl_lock);
@@ -426,9 +370,9 @@ static void ll_agl_add(struct ll_statahead_info *sai,
igrab(inode);
spin_lock(&parent->lli_agl_lock);
- if (list_empty(&sai->sai_entries_agl))
+ if (list_empty(&sai->sai_agls))
added = 1;
- list_add_tail(&child->lli_agl_list, &sai->sai_entries_agl);
+ list_add_tail(&child->lli_agl_list, &sai->sai_agls);
spin_unlock(&parent->lli_agl_lock);
} else {
spin_unlock(&child->lli_agl_lock);
@@ -438,8 +382,10 @@ static void ll_agl_add(struct ll_statahead_info *sai,
wake_up(&sai->sai_agl_thread.t_ctl_waitq);
}
-static struct ll_statahead_info *ll_sai_alloc(void)
+/* allocate sai */
+static struct ll_statahead_info *ll_sai_alloc(struct dentry *dentry)
{
+ struct ll_inode_info *lli = ll_i2info(dentry->d_inode);
struct ll_statahead_info *sai;
int i;
@@ -447,24 +393,18 @@ static struct ll_statahead_info *ll_sai_alloc(void)
if (!sai)
return NULL;
+ sai->sai_dentry = dget(dentry);
atomic_set(&sai->sai_refcount, 1);
- spin_lock(&sai_generation_lock);
- sai->sai_generation = ++sai_generation;
- if (unlikely(sai_generation == 0))
- sai->sai_generation = ++sai_generation;
- spin_unlock(&sai_generation_lock);
-
sai->sai_max = LL_SA_RPC_MIN;
sai->sai_index = 1;
init_waitqueue_head(&sai->sai_waitq);
init_waitqueue_head(&sai->sai_thread.t_ctl_waitq);
init_waitqueue_head(&sai->sai_agl_thread.t_ctl_waitq);
+ INIT_LIST_HEAD(&sai->sai_interim_entries);
INIT_LIST_HEAD(&sai->sai_entries);
- INIT_LIST_HEAD(&sai->sai_entries_received);
- INIT_LIST_HEAD(&sai->sai_entries_stated);
- INIT_LIST_HEAD(&sai->sai_entries_agl);
+ INIT_LIST_HEAD(&sai->sai_agls);
for (i = 0; i < LL_SA_CACHE_SIZE; i++) {
INIT_LIST_HEAD(&sai->sai_cache[i]);
@@ -472,63 +412,74 @@ static struct ll_statahead_info *ll_sai_alloc(void)
}
atomic_set(&sai->sai_cache_count, 0);
+ spin_lock(&sai_generation_lock);
+ lli->lli_sa_generation = ++sai_generation;
+ if (unlikely(!sai_generation))
+ lli->lli_sa_generation = ++sai_generation;
+ spin_unlock(&sai_generation_lock);
+
return sai;
}
-static inline struct ll_statahead_info *
-ll_sai_get(struct ll_statahead_info *sai)
+/* free sai */
+static inline void ll_sai_free(struct ll_statahead_info *sai)
{
- atomic_inc(&sai->sai_refcount);
+ LASSERT(sai->sai_dentry);
+ dput(sai->sai_dentry);
+ kfree(sai);
+}
+
+/*
+ * take refcount of sai if sai for @dir exists, which means statahead is on for
+ * this directory.
+ */
+static inline struct ll_statahead_info *ll_sai_get(struct inode *dir)
+{
+ struct ll_inode_info *lli = ll_i2info(dir);
+ struct ll_statahead_info *sai = NULL;
+
+ spin_lock(&lli->lli_sa_lock);
+ sai = lli->lli_sai;
+ if (sai)
+ atomic_inc(&sai->sai_refcount);
+ spin_unlock(&lli->lli_sa_lock);
+
return sai;
}
+/*
+ * put sai refcount after use, if refcount reaches zero, free sai and sa_entries
+ * attached to it.
+ */
static void ll_sai_put(struct ll_statahead_info *sai)
{
- struct inode *inode = sai->sai_inode;
- struct ll_inode_info *lli = ll_i2info(inode);
+ struct ll_inode_info *lli = ll_i2info(sai->sai_dentry->d_inode);
if (atomic_dec_and_lock(&sai->sai_refcount, &lli->lli_sa_lock)) {
- struct ll_sa_entry *entry, *next;
-
- if (unlikely(atomic_read(&sai->sai_refcount) > 0)) {
- /* It is race case, the interpret callback just hold
- * a reference count
- */
- spin_unlock(&lli->lli_sa_lock);
- return;
- }
-
- LASSERT(!lli->lli_opendir_key);
- LASSERT(thread_is_stopped(&sai->sai_thread));
- LASSERT(thread_is_stopped(&sai->sai_agl_thread));
+ struct ll_sb_info *sbi = ll_i2sbi(sai->sai_dentry->d_inode);
+ struct sa_entry *entry, *next;
lli->lli_sai = NULL;
- lli->lli_opendir_pid = 0;
spin_unlock(&lli->lli_sa_lock);
- if (sai->sai_sent > sai->sai_replied)
- CDEBUG(D_READA, "statahead for dir "DFID
- " does not finish: [sent:%llu] [replied:%llu]\n",
- PFID(&lli->lli_fid),
- sai->sai_sent, sai->sai_replied);
+ LASSERT(thread_is_stopped(&sai->sai_thread));
+ LASSERT(thread_is_stopped(&sai->sai_agl_thread));
+ LASSERT(sai->sai_sent == sai->sai_replied);
+ LASSERT(!sa_has_callback(sai));
list_for_each_entry_safe(entry, next, &sai->sai_entries,
- se_link)
- do_sa_entry_fini(sai, entry);
-
- LASSERT(list_empty(&sai->sai_entries));
- LASSERT(list_empty(&sai->sai_entries_received));
- LASSERT(list_empty(&sai->sai_entries_stated));
+ se_list)
+ sa_kill(sai, entry);
LASSERT(atomic_read(&sai->sai_cache_count) == 0);
- LASSERT(list_empty(&sai->sai_entries_agl));
+ LASSERT(list_empty(&sai->sai_agls));
- iput(inode);
- kfree(sai);
+ ll_sai_free(sai);
+ atomic_dec(&sbi->ll_sa_running);
}
}
-/* Do NOT forget to drop inode refcount when into sai_entries_agl. */
+/* Do NOT forget to drop inode refcount when into sai_agls. */
static void ll_agl_trigger(struct inode *inode, struct ll_statahead_info *sai)
{
struct ll_inode_info *lli = ll_i2info(inode);
@@ -588,29 +539,21 @@ static void ll_agl_trigger(struct inode *inode, struct ll_statahead_info *sai)
iput(inode);
}
-static void ll_post_statahead(struct ll_statahead_info *sai)
+/*
+ * prepare inode for sa entry, add it into agl list, now sa_entry is ready
+ * to be used by scanner process.
+ */
+static void sa_instantiate(struct ll_statahead_info *sai,
+ struct sa_entry *entry)
{
- struct inode *dir = sai->sai_inode;
+ struct inode *dir = sai->sai_dentry->d_inode;
struct inode *child;
- struct ll_inode_info *lli = ll_i2info(dir);
- struct ll_sa_entry *entry;
struct md_enqueue_info *minfo;
struct lookup_intent *it;
struct ptlrpc_request *req;
struct mdt_body *body;
int rc = 0;
- spin_lock(&lli->lli_sa_lock);
- if (unlikely(list_empty(&sai->sai_entries_received))) {
- spin_unlock(&lli->lli_sa_lock);
- return;
- }
- entry = list_entry(sai->sai_entries_received.next,
- struct ll_sa_entry, se_list);
- atomic_inc(&entry->se_refcount);
- list_del_init(&entry->se_list);
- spin_unlock(&lli->lli_sa_lock);
-
LASSERT(entry->se_handle != 0);
minfo = entry->se_minfo;
@@ -632,7 +575,7 @@ static void ll_post_statahead(struct ll_statahead_info *sai)
/* XXX: No fid in reply, this is probably cross-ref case.
* SA can't handle it yet.
*/
- if (body->valid & OBD_MD_MDS) {
+ if (body->mbo_valid & OBD_MD_MDS) {
rc = -EAGAIN;
goto out;
}
@@ -641,7 +584,7 @@ static void ll_post_statahead(struct ll_statahead_info *sai)
* revalidate.
*/
/* unlinked and re-created with the same name */
- if (unlikely(!lu_fid_eq(&minfo->mi_data.op_fid2, &body->fid1))) {
+ if (unlikely(!lu_fid_eq(&minfo->mi_data.op_fid2, &body->mbo_fid1))) {
entry->se_inode = NULL;
iput(child);
child = NULL;
@@ -659,8 +602,9 @@ static void ll_post_statahead(struct ll_statahead_info *sai)
if (rc)
goto out;
- CDEBUG(D_DLMTRACE, "%s: setting l_data to inode "DFID"%p\n",
+ CDEBUG(D_READA, "%s: setting %.*s" DFID " l_data to inode %p\n",
ll_get_fsname(child->i_sb, NULL, 0),
+ entry->se_qstr.len, entry->se_qstr.name,
PFID(ll_inode2fid(child)), child);
ll_set_lock_data(ll_i2sbi(dir)->ll_md_exp, child, it, NULL);
@@ -670,34 +614,75 @@ static void ll_post_statahead(struct ll_statahead_info *sai)
ll_agl_add(sai, child, entry->se_index);
out:
- /* The "ll_sa_entry_to_stated()" will drop related ldlm ibits lock
- * reference count by calling "ll_intent_drop_lock()" in spite of the
- * above operations failed or not. Do not worry about calling
- * "ll_intent_drop_lock()" more than once.
+ /*
+ * sa_make_ready() will drop ldlm ibits lock refcount by calling
+ * ll_intent_drop_lock() in spite of failures. Do not worry about
+ * calling ll_intent_drop_lock() more than once.
*/
- rc = ll_sa_entry_to_stated(sai, entry,
- rc < 0 ? SA_ENTRY_INVA : SA_ENTRY_SUCC);
- if (rc == 0 && entry->se_index == sai->sai_index_wait)
- wake_up(&sai->sai_waitq);
- ll_sa_entry_put(sai, entry);
+ sa_make_ready(sai, entry, rc);
}
+/* once there are async stat replies, instantiate sa_entry from replies */
+static void sa_handle_callback(struct ll_statahead_info *sai)
+{
+ struct ll_inode_info *lli;
+
+ lli = ll_i2info(sai->sai_dentry->d_inode);
+
+ while (sa_has_callback(sai)) {
+ struct sa_entry *entry;
+
+ spin_lock(&lli->lli_sa_lock);
+ if (unlikely(!sa_has_callback(sai))) {
+ spin_unlock(&lli->lli_sa_lock);
+ break;
+ }
+ entry = list_entry(sai->sai_interim_entries.next,
+ struct sa_entry, se_list);
+ list_del_init(&entry->se_list);
+ spin_unlock(&lli->lli_sa_lock);
+
+ sa_instantiate(sai, entry);
+ }
+}
+
+/*
+ * callback for async stat, because this is called in ptlrpcd context, we only
+ * put sa_entry in sai_cb_entries list, and let sa_handle_callback() to really
+ * prepare inode and instantiate sa_entry later.
+ */
static int ll_statahead_interpret(struct ptlrpc_request *req,
struct md_enqueue_info *minfo, int rc)
{
struct lookup_intent *it = &minfo->mi_it;
struct inode *dir = minfo->mi_dir;
struct ll_inode_info *lli = ll_i2info(dir);
- struct ll_statahead_info *sai = NULL;
- struct ll_sa_entry *entry;
- __u64 handle = 0;
- int wakeup;
+ struct ll_statahead_info *sai = lli->lli_sai;
+ struct sa_entry *entry = (struct sa_entry *)minfo->mi_cbdata;
+ __u64 handle = 0;
+ bool wakeup;
if (it_disposition(it, DISP_LOOKUP_NEG))
rc = -ENOENT;
- if (rc == 0) {
- /* release ibits lock ASAP to avoid deadlock when statahead
+ /*
+ * because statahead thread will wait for all inflight RPC to finish,
+ * sai should be always valid, no need to refcount
+ */
+ LASSERT(sai);
+ LASSERT(!thread_is_stopped(&sai->sai_thread));
+ LASSERT(entry);
+
+ CDEBUG(D_READA, "sa_entry %.*s rc %d\n",
+ entry->se_qstr.len, entry->se_qstr.name, rc);
+
+ if (rc) {
+ ll_intent_release(it);
+ iput(dir);
+ kfree(minfo);
+ } else {
+ /*
+ * release ibits lock ASAP to avoid deadlock when statahead
* thread enqueues lock on parent in readdir and another
* process enqueues lock on child with parent lock held, eg.
* unlink.
@@ -707,65 +692,32 @@ static int ll_statahead_interpret(struct ptlrpc_request *req,
}
spin_lock(&lli->lli_sa_lock);
- /* stale entry */
- if (unlikely(!lli->lli_sai ||
- lli->lli_sai->sai_generation != minfo->mi_generation)) {
- spin_unlock(&lli->lli_sa_lock);
- rc = -ESTALE;
- goto out;
+ if (rc) {
+ wakeup = __sa_make_ready(sai, entry, rc);
} else {
- sai = ll_sai_get(lli->lli_sai);
- if (unlikely(!thread_is_running(&sai->sai_thread))) {
- sai->sai_replied++;
- spin_unlock(&lli->lli_sa_lock);
- rc = -EBADFD;
- goto out;
- }
-
- entry = ll_sa_entry_get_byindex(sai, minfo->mi_cbdata);
- if (!entry) {
- sai->sai_replied++;
- spin_unlock(&lli->lli_sa_lock);
- rc = -EIDRM;
- goto out;
- }
-
- if (rc != 0) {
- do_sa_entry_to_stated(sai, entry, SA_ENTRY_INVA);
- wakeup = (entry->se_index == sai->sai_index_wait);
- } else {
- entry->se_minfo = minfo;
- entry->se_req = ptlrpc_request_addref(req);
- /* Release the async ibits lock ASAP to avoid deadlock
- * when statahead thread tries to enqueue lock on parent
- * for readpage and other tries to enqueue lock on child
- * with parent's lock held, for example: unlink.
- */
- entry->se_handle = handle;
- wakeup = list_empty(&sai->sai_entries_received);
- list_add_tail(&entry->se_list,
- &sai->sai_entries_received);
- }
- sai->sai_replied++;
- spin_unlock(&lli->lli_sa_lock);
-
- ll_sa_entry_put(sai, entry);
- if (wakeup)
- wake_up(&sai->sai_thread.t_ctl_waitq);
+ entry->se_minfo = minfo;
+ entry->se_req = ptlrpc_request_addref(req);
+ /*
+ * Release the async ibits lock ASAP to avoid deadlock
+ * when statahead thread tries to enqueue lock on parent
+ * for readpage and other tries to enqueue lock on child
+ * with parent's lock held, for example: unlink.
+ */
+ entry->se_handle = handle;
+ wakeup = !sa_has_callback(sai);
+ list_add_tail(&entry->se_list, &sai->sai_interim_entries);
}
+ sai->sai_replied++;
+
+ if (wakeup)
+ wake_up(&sai->sai_thread.t_ctl_waitq);
+ spin_unlock(&lli->lli_sa_lock);
-out:
- if (rc != 0) {
- ll_intent_release(it);
- iput(dir);
- kfree(minfo);
- }
- if (sai)
- ll_sai_put(sai);
return rc;
}
-static void sa_args_fini(struct md_enqueue_info *minfo,
+/* finish async stat RPC arguments */
+static void sa_fini_data(struct md_enqueue_info *minfo,
struct ldlm_enqueue_info *einfo)
{
LASSERT(minfo && einfo);
@@ -777,12 +729,11 @@ static void sa_args_fini(struct md_enqueue_info *minfo,
/**
* prepare arguments for async stat RPC.
*/
-static int sa_args_init(struct inode *dir, struct inode *child,
- struct ll_sa_entry *entry, struct md_enqueue_info **pmi,
+static int sa_prep_data(struct inode *dir, struct inode *child,
+ struct sa_entry *entry, struct md_enqueue_info **pmi,
struct ldlm_enqueue_info **pei)
{
const struct qstr *qstr = &entry->se_qstr;
- struct ll_inode_info *lli = ll_i2info(dir);
struct md_enqueue_info *minfo;
struct ldlm_enqueue_info *einfo;
struct md_op_data *op_data;
@@ -808,8 +759,7 @@ static int sa_args_init(struct inode *dir, struct inode *child,
minfo->mi_it.it_op = IT_GETATTR;
minfo->mi_dir = igrab(dir);
minfo->mi_cb = ll_statahead_interpret;
- minfo->mi_generation = lli->lli_sai->sai_generation;
- minfo->mi_cbdata = entry->se_index;
+ minfo->mi_cbdata = entry;
einfo->ei_type = LDLM_IBITS;
einfo->ei_mode = it_to_lock_mode(&minfo->mi_it);
@@ -824,31 +774,33 @@ static int sa_args_init(struct inode *dir, struct inode *child,
return 0;
}
-static int do_sa_lookup(struct inode *dir, struct ll_sa_entry *entry)
+/* async stat for file not found in dcache */
+static int sa_lookup(struct inode *dir, struct sa_entry *entry)
{
struct md_enqueue_info *minfo;
struct ldlm_enqueue_info *einfo;
int rc;
- rc = sa_args_init(dir, NULL, entry, &minfo, &einfo);
+ rc = sa_prep_data(dir, NULL, entry, &minfo, &einfo);
if (rc)
return rc;
rc = md_intent_getattr_async(ll_i2mdexp(dir), minfo, einfo);
- if (rc < 0)
- sa_args_fini(minfo, einfo);
+ if (rc)
+ sa_fini_data(minfo, einfo);
return rc;
}
/**
- * similar to ll_revalidate_it().
- * \retval 1 -- dentry valid
- * \retval 0 -- will send stat-ahead request
- * \retval others -- prepare stat-ahead request failed
+ * async stat for file found in dcache, similar to .revalidate
+ *
+ * \retval 1 dentry valid, no RPC sent
+ * \retval 0 dentry invalid, will send async stat RPC
+ * \retval negative number upon error
*/
-static int do_sa_revalidate(struct inode *dir, struct ll_sa_entry *entry,
- struct dentry *dentry)
+static int sa_revalidate(struct inode *dir, struct sa_entry *entry,
+ struct dentry *dentry)
{
struct inode *inode = d_inode(dentry);
struct lookup_intent it = { .it_op = IT_GETATTR,
@@ -872,7 +824,7 @@ static int do_sa_revalidate(struct inode *dir, struct ll_sa_entry *entry,
return 1;
}
- rc = sa_args_init(dir, inode, entry, &minfo, &einfo);
+ rc = sa_prep_data(dir, inode, entry, &minfo, &einfo);
if (rc) {
entry->se_inode = NULL;
iput(inode);
@@ -880,56 +832,50 @@ static int do_sa_revalidate(struct inode *dir, struct ll_sa_entry *entry,
}
rc = md_intent_getattr_async(ll_i2mdexp(dir), minfo, einfo);
- if (rc < 0) {
+ if (rc) {
entry->se_inode = NULL;
iput(inode);
- sa_args_fini(minfo, einfo);
+ sa_fini_data(minfo, einfo);
}
return rc;
}
-static void ll_statahead_one(struct dentry *parent, const char *entry_name,
- int entry_name_len)
+/* async stat for file with @name */
+static void sa_statahead(struct dentry *parent, const char *name, int len)
{
struct inode *dir = d_inode(parent);
struct ll_inode_info *lli = ll_i2info(dir);
struct ll_statahead_info *sai = lli->lli_sai;
struct dentry *dentry = NULL;
- struct ll_sa_entry *entry;
+ struct sa_entry *entry;
int rc;
- int rc1;
- entry = ll_sa_entry_alloc(parent, sai, sai->sai_index, entry_name,
- entry_name_len);
+ entry = sa_alloc(parent, sai, sai->sai_index, name, len);
if (IS_ERR(entry))
return;
dentry = d_lookup(parent, &entry->se_qstr);
if (!dentry) {
- rc = do_sa_lookup(dir, entry);
+ rc = sa_lookup(dir, entry);
} else {
- rc = do_sa_revalidate(dir, entry, dentry);
+ rc = sa_revalidate(dir, entry, dentry);
if (rc == 1 && agl_should_run(sai, d_inode(dentry)))
ll_agl_add(sai, d_inode(dentry), entry->se_index);
+ }
+ if (dentry)
dput(dentry);
- }
- if (rc) {
- rc1 = ll_sa_entry_to_stated(sai, entry,
- rc < 0 ? SA_ENTRY_INVA : SA_ENTRY_SUCC);
- if (rc1 == 0 && entry->se_index == sai->sai_index_wait)
- wake_up(&sai->sai_waitq);
- } else {
+ if (rc)
+ sa_make_ready(sai, entry, rc);
+ else
sai->sai_sent++;
- }
sai->sai_index++;
- /* drop one refcount on entry by ll_sa_entry_alloc */
- ll_sa_entry_put(sai, entry);
}
+/* async glimpse (agl) thread main function */
static int ll_agl_thread(void *arg)
{
struct dentry *parent = arg;
@@ -937,10 +883,12 @@ static int ll_agl_thread(void *arg)
struct ll_inode_info *plli = ll_i2info(dir);
struct ll_inode_info *clli;
struct ll_sb_info *sbi = ll_i2sbi(dir);
- struct ll_statahead_info *sai = ll_sai_get(plli->lli_sai);
- struct ptlrpc_thread *thread = &sai->sai_agl_thread;
+ struct ll_statahead_info *sai;
+ struct ptlrpc_thread *thread;
struct l_wait_info lwi = { 0 };
+ sai = ll_sai_get(dir);
+ thread = &sai->sai_agl_thread;
thread->t_pid = current_pid();
CDEBUG(D_READA, "agl thread started: sai %p, parent %pd\n",
sai, parent);
@@ -959,7 +907,7 @@ static int ll_agl_thread(void *arg)
while (1) {
l_wait_event(thread->t_ctl_waitq,
- !list_empty(&sai->sai_entries_agl) ||
+ !list_empty(&sai->sai_agls) ||
!thread_is_running(thread),
&lwi);
@@ -970,8 +918,8 @@ static int ll_agl_thread(void *arg)
/* The statahead thread maybe help to process AGL entries,
* so check whether list empty again.
*/
- if (!list_empty(&sai->sai_entries_agl)) {
- clli = list_entry(sai->sai_entries_agl.next,
+ if (!list_empty(&sai->sai_agls)) {
+ clli = list_entry(sai->sai_agls.next,
struct ll_inode_info, lli_agl_list);
list_del_init(&clli->lli_agl_list);
spin_unlock(&plli->lli_agl_lock);
@@ -983,8 +931,8 @@ static int ll_agl_thread(void *arg)
spin_lock(&plli->lli_agl_lock);
sai->sai_agl_valid = 0;
- while (!list_empty(&sai->sai_entries_agl)) {
- clli = list_entry(sai->sai_entries_agl.next,
+ while (!list_empty(&sai->sai_agls)) {
+ clli = list_entry(sai->sai_agls.next,
struct ll_inode_info, lli_agl_list);
list_del_init(&clli->lli_agl_list);
spin_unlock(&plli->lli_agl_lock);
@@ -1001,6 +949,7 @@ static int ll_agl_thread(void *arg)
return 0;
}
+/* start agl thread */
static void ll_start_agl(struct dentry *parent, struct ll_statahead_info *sai)
{
struct ptlrpc_thread *thread = &sai->sai_agl_thread;
@@ -1025,58 +974,71 @@ static void ll_start_agl(struct dentry *parent, struct ll_statahead_info *sai)
&lwi);
}
+/* statahead thread main function */
static int ll_statahead_thread(void *arg)
{
struct dentry *parent = arg;
struct inode *dir = d_inode(parent);
- struct ll_inode_info *plli = ll_i2info(dir);
- struct ll_inode_info *clli;
+ struct ll_inode_info *lli = ll_i2info(dir);
struct ll_sb_info *sbi = ll_i2sbi(dir);
- struct ll_statahead_info *sai = ll_sai_get(plli->lli_sai);
- struct ptlrpc_thread *thread = &sai->sai_thread;
- struct ptlrpc_thread *agl_thread = &sai->sai_agl_thread;
- struct page *page;
+ struct ll_statahead_info *sai;
+ struct ptlrpc_thread *sa_thread;
+ struct ptlrpc_thread *agl_thread;
+ struct page *page = NULL;
__u64 pos = 0;
int first = 0;
int rc = 0;
- struct ll_dir_chain chain;
+ struct md_op_data *op_data;
struct l_wait_info lwi = { 0 };
- thread->t_pid = current_pid();
+ sai = ll_sai_get(dir);
+ sa_thread = &sai->sai_thread;
+ agl_thread = &sai->sai_agl_thread;
+ sa_thread->t_pid = current_pid();
CDEBUG(D_READA, "statahead thread starting: sai %p, parent %pd\n",
sai, parent);
+ op_data = ll_prep_md_op_data(NULL, dir, dir, NULL, 0, 0,
+ LUSTRE_OPC_ANY, dir);
+ if (IS_ERR(op_data)) {
+ rc = PTR_ERR(op_data);
+ goto out;
+ }
+
+ op_data->op_max_pages = ll_i2sbi(dir)->ll_md_brw_pages;
+
if (sbi->ll_flags & LL_SBI_AGL_ENABLED)
ll_start_agl(parent, sai);
atomic_inc(&sbi->ll_sa_total);
- spin_lock(&plli->lli_sa_lock);
- if (thread_is_init(thread))
+ spin_lock(&lli->lli_sa_lock);
+ if (thread_is_init(sa_thread))
/* If someone else has changed the thread state
* (e.g. already changed to SVC_STOPPING), we can't just
* blindly overwrite that setting.
*/
- thread_set_flags(thread, SVC_RUNNING);
- spin_unlock(&plli->lli_sa_lock);
- wake_up(&thread->t_ctl_waitq);
-
- ll_dir_chain_init(&chain);
- page = ll_get_dir_page(dir, pos, &chain);
+ thread_set_flags(sa_thread, SVC_RUNNING);
+ spin_unlock(&lli->lli_sa_lock);
+ wake_up(&sa_thread->t_ctl_waitq);
- while (1) {
+ while (pos != MDS_DIR_END_OFF && thread_is_running(sa_thread)) {
struct lu_dirpage *dp;
struct lu_dirent *ent;
+ sai->sai_in_readpage = 1;
+ page = ll_get_dir_page(dir, op_data, pos);
+ sai->sai_in_readpage = 0;
if (IS_ERR(page)) {
rc = PTR_ERR(page);
- CDEBUG(D_READA, "error reading dir "DFID" at %llu/%llu: [rc %d] [parent %u]\n",
+ CDEBUG(D_READA, "error reading dir "DFID" at %llu/%llu: opendir_pid = %u: rc = %d\n",
PFID(ll_inode2fid(dir)), pos, sai->sai_index,
- rc, plli->lli_opendir_pid);
- goto out;
+ lli->lli_opendir_pid, rc);
+ break;
}
dp = page_address(page);
- for (ent = lu_dirent_start(dp); ent;
+ for (ent = lu_dirent_start(dp);
+ ent && thread_is_running(sa_thread) && !sa_low_hit(sai);
ent = lu_dirent_next(ent)) {
__u64 hash;
int namelen;
@@ -1123,123 +1085,79 @@ static int ll_statahead_thread(void *arg)
if (unlikely(++first == 1))
continue;
-keep_it:
- l_wait_event(thread->t_ctl_waitq,
- !sa_sent_full(sai) ||
- !list_empty(&sai->sai_entries_received) ||
- !list_empty(&sai->sai_entries_agl) ||
- !thread_is_running(thread),
- &lwi);
-
-interpret_it:
- while (!list_empty(&sai->sai_entries_received))
- ll_post_statahead(sai);
-
- if (unlikely(!thread_is_running(thread))) {
- ll_release_page(page, 0);
- rc = 0;
- goto out;
- }
+ /* wait for spare statahead window */
+ do {
+ l_wait_event(sa_thread->t_ctl_waitq,
+ !sa_sent_full(sai) ||
+ sa_has_callback(sai) ||
+ !list_empty(&sai->sai_agls) ||
+ !thread_is_running(sa_thread),
+ &lwi);
+ sa_handle_callback(sai);
- /* If no window for metadata statahead, but there are
- * some AGL entries to be triggered, then try to help
- * to process the AGL entries.
- */
- if (sa_sent_full(sai)) {
- spin_lock(&plli->lli_agl_lock);
- while (!list_empty(&sai->sai_entries_agl)) {
- clli = list_entry(sai->sai_entries_agl.next,
+ spin_lock(&lli->lli_agl_lock);
+ while (sa_sent_full(sai) &&
+ !agl_list_empty(sai)) {
+ struct ll_inode_info *clli;
+
+ clli = list_entry(sai->sai_agls.next,
struct ll_inode_info, lli_agl_list);
list_del_init(&clli->lli_agl_list);
- spin_unlock(&plli->lli_agl_lock);
+ spin_unlock(&lli->lli_agl_lock);
+
ll_agl_trigger(&clli->lli_vfs_inode,
sai);
- if (!list_empty(&sai->sai_entries_received))
- goto interpret_it;
-
- if (unlikely(
- !thread_is_running(thread))) {
- ll_release_page(page, 0);
- rc = 0;
- goto out;
- }
-
- if (!sa_sent_full(sai))
- goto do_it;
-
- spin_lock(&plli->lli_agl_lock);
+ spin_lock(&lli->lli_agl_lock);
}
- spin_unlock(&plli->lli_agl_lock);
+ spin_unlock(&lli->lli_agl_lock);
+ } while (sa_sent_full(sai) &&
+ thread_is_running(sa_thread));
- goto keep_it;
- }
-
-do_it:
- ll_statahead_one(parent, name, namelen);
+ sa_statahead(parent, name, namelen);
}
- pos = le64_to_cpu(dp->ldp_hash_end);
- if (pos == MDS_DIR_END_OFF) {
- /*
- * End of directory reached.
- */
- ll_release_page(page, 0);
- while (1) {
- l_wait_event(thread->t_ctl_waitq,
- !list_empty(&sai->sai_entries_received) ||
- sai->sai_sent == sai->sai_replied ||
- !thread_is_running(thread),
- &lwi);
- while (!list_empty(&sai->sai_entries_received))
- ll_post_statahead(sai);
+ pos = le64_to_cpu(dp->ldp_hash_end);
+ ll_release_page(dir, page,
+ le32_to_cpu(dp->ldp_flags) & LDF_COLLIDE);
- if (unlikely(!thread_is_running(thread))) {
- rc = 0;
- goto out;
- }
+ if (sa_low_hit(sai)) {
+ rc = -EFAULT;
+ atomic_inc(&sbi->ll_sa_wrong);
+ CDEBUG(D_READA, "Statahead for dir "DFID" hit ratio too low: hit/miss %llu/%llu, sent/replied %llu/%llu, stopping statahead thread: pid %d\n",
+ PFID(&lli->lli_fid), sai->sai_hit,
+ sai->sai_miss, sai->sai_sent,
+ sai->sai_replied, current_pid());
+ break;
+ }
+ }
+ ll_finish_md_op_data(op_data);
- if (sai->sai_sent == sai->sai_replied &&
- list_empty(&sai->sai_entries_received))
- break;
- }
+ if (rc < 0) {
+ spin_lock(&lli->lli_sa_lock);
+ thread_set_flags(sa_thread, SVC_STOPPING);
+ lli->lli_sa_enabled = 0;
+ spin_unlock(&lli->lli_sa_lock);
+ }
- spin_lock(&plli->lli_agl_lock);
- while (!list_empty(&sai->sai_entries_agl) &&
- thread_is_running(thread)) {
- clli = list_entry(sai->sai_entries_agl.next,
- struct ll_inode_info, lli_agl_list);
- list_del_init(&clli->lli_agl_list);
- spin_unlock(&plli->lli_agl_lock);
- ll_agl_trigger(&clli->lli_vfs_inode, sai);
- spin_lock(&plli->lli_agl_lock);
- }
- spin_unlock(&plli->lli_agl_lock);
+ /*
+ * statahead is finished, but statahead entries need to be cached, wait
+ * for file release to stop me.
+ */
+ while (thread_is_running(sa_thread)) {
+ l_wait_event(sa_thread->t_ctl_waitq,
+ sa_has_callback(sai) ||
+ !agl_list_empty(sai) ||
+ !thread_is_running(sa_thread),
+ &lwi);
- rc = 0;
- goto out;
- } else if (1) {
- /*
- * chain is exhausted.
- * Normal case: continue to the next page.
- */
- ll_release_page(page, le32_to_cpu(dp->ldp_flags) &
- LDF_COLLIDE);
- page = ll_get_dir_page(dir, pos, &chain);
- } else {
- LASSERT(le32_to_cpu(dp->ldp_flags) & LDF_COLLIDE);
- ll_release_page(page, 1);
- /*
- * go into overflow page.
- */
- }
+ sa_handle_callback(sai);
}
-
out:
if (sai->sai_agl_valid) {
- spin_lock(&plli->lli_agl_lock);
+ spin_lock(&lli->lli_agl_lock);
thread_set_flags(agl_thread, SVC_STOPPING);
- spin_unlock(&plli->lli_agl_lock);
+ spin_unlock(&lli->lli_agl_lock);
wake_up(&agl_thread->t_ctl_waitq);
CDEBUG(D_READA, "stop agl thread: sai %p pid %u\n",
@@ -1249,84 +1167,93 @@ out:
&lwi);
} else {
/* Set agl_thread flags anyway. */
- thread_set_flags(&sai->sai_agl_thread, SVC_STOPPED);
+ thread_set_flags(agl_thread, SVC_STOPPED);
}
- ll_dir_chain_fini(&chain);
- spin_lock(&plli->lli_sa_lock);
- if (!list_empty(&sai->sai_entries_received)) {
- thread_set_flags(thread, SVC_STOPPING);
- spin_unlock(&plli->lli_sa_lock);
-
- /* To release the resources held by received entries. */
- while (!list_empty(&sai->sai_entries_received))
- ll_post_statahead(sai);
- spin_lock(&plli->lli_sa_lock);
+ /*
+ * wait for inflight statahead RPCs to finish, and then we can free sai
+ * safely because statahead RPC will access sai data
+ */
+ while (sai->sai_sent != sai->sai_replied) {
+ /* in case we're not woken up, timeout wait */
+ lwi = LWI_TIMEOUT(msecs_to_jiffies(MSEC_PER_SEC >> 3),
+ NULL, NULL);
+ l_wait_event(sa_thread->t_ctl_waitq,
+ sai->sai_sent == sai->sai_replied, &lwi);
}
- thread_set_flags(thread, SVC_STOPPED);
- spin_unlock(&plli->lli_sa_lock);
- wake_up(&sai->sai_waitq);
- wake_up(&thread->t_ctl_waitq);
- ll_sai_put(sai);
- dput(parent);
+
+ /* release resources held by statahead RPCs */
+ sa_handle_callback(sai);
+
+ spin_lock(&lli->lli_sa_lock);
+ thread_set_flags(sa_thread, SVC_STOPPED);
+ spin_unlock(&lli->lli_sa_lock);
+
CDEBUG(D_READA, "statahead thread stopped: sai %p, parent %pd\n",
sai, parent);
+
+ wake_up(&sai->sai_waitq);
+ wake_up(&sa_thread->t_ctl_waitq);
+ ll_sai_put(sai);
+
return rc;
}
-/**
- * called in ll_file_release().
- */
-void ll_stop_statahead(struct inode *dir, void *key)
+/* authorize opened dir handle @key to statahead */
+void ll_authorize_statahead(struct inode *dir, void *key)
{
struct ll_inode_info *lli = ll_i2info(dir);
- if (unlikely(!key))
- return;
-
spin_lock(&lli->lli_sa_lock);
- if (lli->lli_opendir_key != key || lli->lli_opendir_pid == 0) {
- spin_unlock(&lli->lli_sa_lock);
- return;
+ if (!lli->lli_opendir_key && !lli->lli_sai) {
+ /*
+ * if lli_sai is not NULL, it means previous statahead is not
+ * finished yet, we'd better not start a new statahead for now.
+ */
+ LASSERT(!lli->lli_opendir_pid);
+ lli->lli_opendir_key = key;
+ lli->lli_opendir_pid = current_pid();
+ lli->lli_sa_enabled = 1;
}
+ spin_unlock(&lli->lli_sa_lock);
+}
- lli->lli_opendir_key = NULL;
-
- if (lli->lli_sai) {
- struct l_wait_info lwi = { 0 };
- struct ptlrpc_thread *thread = &lli->lli_sai->sai_thread;
+/*
+ * deauthorize opened dir handle @key to statahead, but statahead thread may
+ * still be running, notify it to quit.
+ */
+void ll_deauthorize_statahead(struct inode *dir, void *key)
+{
+ struct ll_inode_info *lli = ll_i2info(dir);
+ struct ll_statahead_info *sai;
- if (!thread_is_stopped(thread)) {
- thread_set_flags(thread, SVC_STOPPING);
- spin_unlock(&lli->lli_sa_lock);
- wake_up(&thread->t_ctl_waitq);
+ LASSERT(lli->lli_opendir_key == key);
+ LASSERT(lli->lli_opendir_pid);
- CDEBUG(D_READA, "stop statahead thread: sai %p pid %u\n",
- lli->lli_sai, (unsigned int)thread->t_pid);
- l_wait_event(thread->t_ctl_waitq,
- thread_is_stopped(thread),
- &lwi);
- } else {
- spin_unlock(&lli->lli_sa_lock);
- }
+ CDEBUG(D_READA, "deauthorize statahead for "DFID"\n",
+ PFID(&lli->lli_fid));
+ spin_lock(&lli->lli_sa_lock);
+ lli->lli_opendir_key = NULL;
+ lli->lli_opendir_pid = 0;
+ lli->lli_sa_enabled = 0;
+ sai = lli->lli_sai;
+ if (sai && thread_is_running(&sai->sai_thread)) {
/*
- * Put the ref which was held when first statahead_enter.
- * It maybe not the last ref for some statahead requests
- * maybe inflight.
+ * statahead thread may not quit yet because it needs to cache
+ * entries, now it's time to tell it to quit.
*/
- ll_sai_put(lli->lli_sai);
- } else {
- lli->lli_opendir_pid = 0;
- spin_unlock(&lli->lli_sa_lock);
+ thread_set_flags(&sai->sai_thread, SVC_STOPPING);
+ wake_up(&sai->sai_thread.t_ctl_waitq);
}
+ spin_unlock(&lli->lli_sa_lock);
}
enum {
/**
* not first dirent, or is "."
*/
- LS_NONE_FIRST_DE = 0,
+ LS_NOT_FIRST_DE = 0,
/**
* the first non-hidden dirent
*/
@@ -1337,17 +1264,26 @@ enum {
LS_FIRST_DOT_DE
};
+/* file is first dirent under @dir */
static int is_first_dirent(struct inode *dir, struct dentry *dentry)
{
- struct ll_dir_chain chain;
const struct qstr *target = &dentry->d_name;
+ struct md_op_data *op_data;
struct page *page;
__u64 pos = 0;
int dot_de;
- int rc = LS_NONE_FIRST_DE;
+ int rc = LS_NOT_FIRST_DE;
- ll_dir_chain_init(&chain);
- page = ll_get_dir_page(dir, pos, &chain);
+ op_data = ll_prep_md_op_data(NULL, dir, dir, NULL, 0, 0,
+ LUSTRE_OPC_ANY, dir);
+ if (IS_ERR(op_data))
+ return PTR_ERR(op_data);
+ /**
+ * FIXME choose the start offset of the readdir
+ */
+ op_data->op_max_pages = ll_i2sbi(dir)->ll_md_brw_pages;
+
+ page = ll_get_dir_page(dir, op_data, pos);
while (1) {
struct lu_dirpage *dp;
@@ -1357,9 +1293,10 @@ static int is_first_dirent(struct inode *dir, struct dentry *dentry)
struct ll_inode_info *lli = ll_i2info(dir);
rc = PTR_ERR(page);
- CERROR("error reading dir "DFID" at %llu: [rc %d] [parent %u]\n",
+ CERROR("%s: error reading dir "DFID" at %llu: opendir_pid = %u : rc = %d\n",
+ ll_get_fsname(dir->i_sb, NULL, 0),
PFID(ll_inode2fid(dir)), pos,
- rc, lli->lli_opendir_pid);
+ lli->lli_opendir_pid, rc);
break;
}
@@ -1411,13 +1348,13 @@ static int is_first_dirent(struct inode *dir, struct dentry *dentry)
if (target->len != namelen ||
memcmp(target->name, name, namelen) != 0)
- rc = LS_NONE_FIRST_DE;
+ rc = LS_NOT_FIRST_DE;
else if (!dot_de)
rc = LS_FIRST_DE;
else
rc = LS_FIRST_DOT_DE;
- ll_release_page(page, 0);
+ ll_release_page(dir, page, false);
goto out;
}
pos = le64_to_cpu(dp->ldp_hash_end);
@@ -1425,261 +1362,228 @@ static int is_first_dirent(struct inode *dir, struct dentry *dentry)
/*
* End of directory reached.
*/
- ll_release_page(page, 0);
- break;
- } else if (1) {
+ ll_release_page(dir, page, false);
+ goto out;
+ } else {
/*
* chain is exhausted
* Normal case: continue to the next page.
*/
- ll_release_page(page, le32_to_cpu(dp->ldp_flags) &
- LDF_COLLIDE);
- page = ll_get_dir_page(dir, pos, &chain);
- } else {
- /*
- * go into overflow page.
- */
- LASSERT(le32_to_cpu(dp->ldp_flags) & LDF_COLLIDE);
- ll_release_page(page, 1);
+ ll_release_page(dir, page,
+ le32_to_cpu(dp->ldp_flags) &
+ LDF_COLLIDE);
+ page = ll_get_dir_page(dir, op_data, pos);
}
}
-
out:
- ll_dir_chain_fini(&chain);
+ ll_finish_md_op_data(op_data);
return rc;
}
-static void
-ll_sai_unplug(struct ll_statahead_info *sai, struct ll_sa_entry *entry)
-{
- struct ptlrpc_thread *thread = &sai->sai_thread;
- struct ll_sb_info *sbi = ll_i2sbi(sai->sai_inode);
- int hit;
-
- if (entry && entry->se_stat == SA_ENTRY_SUCC)
- hit = 1;
- else
- hit = 0;
-
- ll_sa_entry_fini(sai, entry);
- if (hit) {
- sai->sai_hit++;
- sai->sai_consecutive_miss = 0;
- sai->sai_max = min(2 * sai->sai_max, sbi->ll_sa_max);
- } else {
- struct ll_inode_info *lli = ll_i2info(sai->sai_inode);
-
- sai->sai_miss++;
- sai->sai_consecutive_miss++;
- if (sa_low_hit(sai) && thread_is_running(thread)) {
- atomic_inc(&sbi->ll_sa_wrong);
- CDEBUG(D_READA, "Statahead for dir " DFID " hit ratio too low: hit/miss %llu/%llu, sent/replied %llu/%llu, stopping statahead thread\n",
- PFID(&lli->lli_fid), sai->sai_hit,
- sai->sai_miss, sai->sai_sent,
- sai->sai_replied);
- spin_lock(&lli->lli_sa_lock);
- if (!thread_is_stopped(thread))
- thread_set_flags(thread, SVC_STOPPING);
- spin_unlock(&lli->lli_sa_lock);
- }
- }
-
- if (!thread_is_stopped(thread))
- wake_up(&thread->t_ctl_waitq);
-}
-
/**
- * Start statahead thread if this is the first dir entry.
- * Otherwise if a thread is started already, wait it until it is ahead of me.
- * \retval 1 -- find entry with lock in cache, the caller needs to do
- * nothing.
- * \retval 0 -- find entry in cache, but without lock, the caller needs
- * refresh from MDS.
- * \retval others -- the caller need to process as non-statahead.
+ * revalidate @dentryp from statahead cache
+ *
+ * \param[in] dir parent directory
+ * \param[in] sai sai structure
+ * \param[out] dentryp pointer to dentry which will be revalidated
+ * \param[in] unplug unplug statahead window only (normally for negative
+ * dentry)
+ * \retval 1 on success, dentry is saved in @dentryp
+ * \retval 0 if revalidation failed (no proper lock on client)
+ * \retval negative number upon error
*/
-int do_statahead_enter(struct inode *dir, struct dentry **dentryp,
- int only_unplug)
+static int revalidate_statahead_dentry(struct inode *dir,
+ struct ll_statahead_info *sai,
+ struct dentry **dentryp,
+ bool unplug)
{
- struct ll_inode_info *lli = ll_i2info(dir);
- struct ll_statahead_info *sai = lli->lli_sai;
- struct dentry *parent;
- struct ll_sa_entry *entry;
- struct ptlrpc_thread *thread;
- struct l_wait_info lwi = { 0 };
- struct task_struct *task;
- int rc = 0;
- struct ll_inode_info *plli;
+ struct sa_entry *entry = NULL;
+ struct l_wait_info lwi = { 0 };
+ struct ll_dentry_data *ldd;
+ struct ll_inode_info *lli;
+ int rc = 0;
- LASSERT(lli->lli_opendir_pid == current_pid());
+ if ((*dentryp)->d_name.name[0] == '.') {
+ if (sai->sai_ls_all ||
+ sai->sai_miss_hidden >= sai->sai_skip_hidden) {
+ /*
+ * Hidden dentry is the first one, or statahead
+ * thread does not skip so many hidden dentries
+ * before "sai_ls_all" enabled as below.
+ */
+ } else {
+ if (!sai->sai_ls_all)
+ /*
+ * It maybe because hidden dentry is not
+ * the first one, "sai_ls_all" was not
+ * set, then "ls -al" missed. Enable
+ * "sai_ls_all" for such case.
+ */
+ sai->sai_ls_all = 1;
- if (sai) {
- thread = &sai->sai_thread;
- if (unlikely(thread_is_stopped(thread) &&
- list_empty(&sai->sai_entries_stated))) {
- /* to release resource */
- ll_stop_statahead(dir, lli->lli_opendir_key);
+ /*
+ * Such "getattr" has been skipped before
+ * "sai_ls_all" enabled as above.
+ */
+ sai->sai_miss_hidden++;
return -EAGAIN;
}
+ }
- if ((*dentryp)->d_name.name[0] == '.') {
- if (sai->sai_ls_all ||
- sai->sai_miss_hidden >= sai->sai_skip_hidden) {
- /*
- * Hidden dentry is the first one, or statahead
- * thread does not skip so many hidden dentries
- * before "sai_ls_all" enabled as below.
- */
- } else {
- if (!sai->sai_ls_all)
- /*
- * It maybe because hidden dentry is not
- * the first one, "sai_ls_all" was not
- * set, then "ls -al" missed. Enable
- * "sai_ls_all" for such case.
- */
- sai->sai_ls_all = 1;
+ if (unplug) {
+ rc = 1;
+ goto out_unplug;
+ }
- /*
- * Such "getattr" has been skipped before
- * "sai_ls_all" enabled as above.
- */
- sai->sai_miss_hidden++;
- return -EAGAIN;
- }
- }
+ entry = sa_get(sai, &(*dentryp)->d_name);
+ if (!entry) {
+ rc = -EAGAIN;
+ goto out_unplug;
+ }
- entry = ll_sa_entry_get_byname(sai, &(*dentryp)->d_name);
- if (!entry || only_unplug) {
- ll_sai_unplug(sai, entry);
- return entry ? 1 : -EAGAIN;
- }
+ /* if statahead is busy in readdir, help it do post-work */
+ if (!sa_ready(entry) && sai->sai_in_readpage)
+ sa_handle_callback(sai);
- if (!ll_sa_entry_stated(entry)) {
- sai->sai_index_wait = entry->se_index;
- lwi = LWI_TIMEOUT_INTR(cfs_time_seconds(30), NULL,
- LWI_ON_SIGNAL_NOOP, NULL);
- rc = l_wait_event(sai->sai_waitq,
- ll_sa_entry_stated(entry) ||
- thread_is_stopped(thread),
- &lwi);
- if (rc < 0) {
- ll_sai_unplug(sai, entry);
- return -EAGAIN;
- }
+ if (!sa_ready(entry)) {
+ sai->sai_index_wait = entry->se_index;
+ lwi = LWI_TIMEOUT_INTR(cfs_time_seconds(30), NULL,
+ LWI_ON_SIGNAL_NOOP, NULL);
+ rc = l_wait_event(sai->sai_waitq, sa_ready(entry), &lwi);
+ if (rc < 0) {
+ /*
+ * entry may not be ready, so it may be used by inflight
+ * statahead RPC, don't free it.
+ */
+ entry = NULL;
+ rc = -EAGAIN;
+ goto out_unplug;
}
+ }
- if (entry->se_stat == SA_ENTRY_SUCC && entry->se_inode) {
- struct inode *inode = entry->se_inode;
- struct lookup_intent it = { .it_op = IT_GETATTR,
- .it_lock_handle =
- entry->se_handle };
- __u64 bits;
-
- rc = md_revalidate_lock(ll_i2mdexp(dir), &it,
- ll_inode2fid(inode), &bits);
- if (rc == 1) {
- if (!d_inode(*dentryp)) {
- struct dentry *alias;
-
- alias = ll_splice_alias(inode,
- *dentryp);
- if (IS_ERR(alias)) {
- ll_sai_unplug(sai, entry);
- return PTR_ERR(alias);
- }
- *dentryp = alias;
- } else if (d_inode(*dentryp) != inode) {
- /* revalidate, but inode is recreated */
- CDEBUG(D_READA, "%s: stale dentry %pd inode "DFID", statahead inode "DFID"\n",
- ll_get_fsname(d_inode(*dentryp)->i_sb, NULL, 0),
- *dentryp,
- PFID(ll_inode2fid(d_inode(*dentryp))),
- PFID(ll_inode2fid(inode)));
- ll_sai_unplug(sai, entry);
- return -ESTALE;
- } else {
- iput(inode);
+ if (entry->se_state == SA_ENTRY_SUCC && entry->se_inode) {
+ struct inode *inode = entry->se_inode;
+ struct lookup_intent it = { .it_op = IT_GETATTR,
+ .it_lock_handle = entry->se_handle };
+ __u64 bits;
+
+ rc = md_revalidate_lock(ll_i2mdexp(dir), &it,
+ ll_inode2fid(inode), &bits);
+ if (rc == 1) {
+ if (!(*dentryp)->d_inode) {
+ struct dentry *alias;
+
+ alias = ll_splice_alias(inode, *dentryp);
+ if (IS_ERR(alias)) {
+ rc = PTR_ERR(alias);
+ goto out_unplug;
}
+ *dentryp = alias;
+ /**
+ * statahead prepared this inode, transfer inode
+ * refcount from sa_entry to dentry
+ */
entry->se_inode = NULL;
-
- if ((bits & MDS_INODELOCK_LOOKUP) &&
- d_lustre_invalid(*dentryp))
- d_lustre_revalidate(*dentryp);
- ll_intent_release(&it);
+ } else if ((*dentryp)->d_inode != inode) {
+ /* revalidate, but inode is recreated */
+ CDEBUG(D_READA,
+ "%s: stale dentry %pd inode "DFID", statahead inode "DFID"\n",
+ ll_get_fsname((*dentryp)->d_inode->i_sb,
+ NULL, 0),
+ *dentryp,
+ PFID(ll_inode2fid((*dentryp)->d_inode)),
+ PFID(ll_inode2fid(inode)));
+ rc = -ESTALE;
+ goto out_unplug;
}
- }
- ll_sai_unplug(sai, entry);
- return rc;
+ if ((bits & MDS_INODELOCK_LOOKUP) &&
+ d_lustre_invalid(*dentryp))
+ d_lustre_revalidate(*dentryp);
+ ll_intent_release(&it);
+ }
}
+out_unplug:
+ /*
+ * statahead cached sa_entry can be used only once, and will be killed
+ * right after use, so if lookup/revalidate accessed statahead cache,
+ * set dentry ldd_sa_generation to parent lli_sa_generation, later if we
+ * stat this file again, we know we've done statahead before, see
+ * dentry_may_statahead().
+ */
+ ldd = ll_d2d(*dentryp);
+ lli = ll_i2info(dir);
+ /* ldd can be NULL if llite lookup failed. */
+ if (ldd)
+ ldd->lld_sa_generation = lli->lli_sa_generation;
+ sa_put(sai, entry);
+ return rc;
+}
+
+/**
+ * start statahead thread
+ *
+ * \param[in] dir parent directory
+ * \param[in] dentry dentry that triggers statahead, normally the first
+ * dirent under @dir
+ * \retval -EAGAIN on success, because when this function is
+ * called, it's already in lookup call, so client should
+ * do it itself instead of waiting for statahead thread
+ * to do it asynchronously.
+ * \retval negative number upon error
+ */
+static int start_statahead_thread(struct inode *dir, struct dentry *dentry)
+{
+ struct ll_inode_info *lli = ll_i2info(dir);
+ struct ll_statahead_info *sai = NULL;
+ struct l_wait_info lwi = { 0 };
+ struct ptlrpc_thread *thread;
+ struct task_struct *task;
+ struct dentry *parent = dentry->d_parent;
+ int rc;
/* I am the "lli_opendir_pid" owner, only me can set "lli_sai". */
- rc = is_first_dirent(dir, *dentryp);
- if (rc == LS_NONE_FIRST_DE) {
+ rc = is_first_dirent(dir, dentry);
+ if (rc == LS_NOT_FIRST_DE) {
/* It is not "ls -{a}l" operation, no need statahead for it. */
- rc = -EAGAIN;
+ rc = -EFAULT;
goto out;
}
- sai = ll_sai_alloc();
+ sai = ll_sai_alloc(parent);
if (!sai) {
rc = -ENOMEM;
goto out;
}
sai->sai_ls_all = (rc == LS_FIRST_DOT_DE);
- sai->sai_inode = igrab(dir);
- if (unlikely(!sai->sai_inode)) {
- CWARN("Do not start stat ahead on dying inode "DFID"\n",
- PFID(&lli->lli_fid));
- rc = -ESTALE;
- goto out;
- }
-
- /* get parent reference count here, and put it in ll_statahead_thread */
- parent = dget((*dentryp)->d_parent);
- if (unlikely(sai->sai_inode != d_inode(parent))) {
- struct ll_inode_info *nlli = ll_i2info(d_inode(parent));
-
- CWARN("Race condition, someone changed %pd just now: old parent "DFID", new parent "DFID"\n",
- *dentryp,
- PFID(&lli->lli_fid), PFID(&nlli->lli_fid));
- dput(parent);
- iput(sai->sai_inode);
- rc = -EAGAIN;
+ /*
+ * if current lli_opendir_key was deauthorized, or dir re-opened by
+ * another process, don't start statahead, otherwise the newly spawned
+ * statahead thread won't be notified to quit.
+ */
+ spin_lock(&lli->lli_sa_lock);
+ if (unlikely(lli->lli_sai || lli->lli_opendir_key ||
+ lli->lli_opendir_pid != current->pid)) {
+ spin_unlock(&lli->lli_sa_lock);
+ rc = -EPERM;
goto out;
}
+ lli->lli_sai = sai;
+ spin_unlock(&lli->lli_sa_lock);
- CDEBUG(D_READA, "start statahead thread: sai %p, parent %pd\n",
- sai, parent);
+ atomic_inc(&ll_i2sbi(parent->d_inode)->ll_sa_running);
- /* The sai buffer already has one reference taken at allocation time,
- * but as soon as we expose the sai by attaching it to the lli that
- * default reference can be dropped by another thread calling
- * ll_stop_statahead. We need to take a local reference to protect
- * the sai buffer while we intend to access it.
- */
- ll_sai_get(sai);
- lli->lli_sai = sai;
+ CDEBUG(D_READA, "start statahead thread: [pid %d] [parent %pd]\n",
+ current_pid(), parent);
- plli = ll_i2info(d_inode(parent));
task = kthread_run(ll_statahead_thread, parent, "ll_sa_%u",
- plli->lli_opendir_pid);
+ lli->lli_opendir_pid);
thread = &sai->sai_thread;
if (IS_ERR(task)) {
rc = PTR_ERR(task);
- CERROR("can't start ll_sa thread, rc: %d\n", rc);
- dput(parent);
- lli->lli_opendir_key = NULL;
- thread_set_flags(thread, SVC_STOPPED);
- thread_set_flags(&sai->sai_agl_thread, SVC_STOPPED);
- /* Drop both our own local reference and the default
- * reference from allocation time.
- */
- ll_sai_put(sai);
- ll_sai_put(sai);
- LASSERT(!lli->lli_sai);
- return -EAGAIN;
+ CERROR("can't start ll_sa thread, rc : %d\n", rc);
+ goto out;
}
l_wait_event(thread->t_ctl_waitq,
@@ -1694,10 +1598,47 @@ int do_statahead_enter(struct inode *dir, struct dentry **dentryp,
return -EAGAIN;
out:
- kfree(sai);
+ /*
+ * once we start statahead thread failed, disable statahead so
+ * that subsequent stat won't waste time to try it.
+ */
spin_lock(&lli->lli_sa_lock);
- lli->lli_opendir_key = NULL;
- lli->lli_opendir_pid = 0;
+ lli->lli_sa_enabled = 0;
+ lli->lli_sai = NULL;
spin_unlock(&lli->lli_sa_lock);
+ if (sai)
+ ll_sai_free(sai);
return rc;
}
+
+/**
+ * statahead entry function, this is called when client getattr on a file, it
+ * will start statahead thread if this is the first dir entry, else revalidate
+ * dentry from statahead cache.
+ *
+ * \param[in] dir parent directory
+ * \param[out] dentryp dentry to getattr
+ * \param[in] unplug unplug statahead window only (normally for negative
+ * dentry)
+ * \retval 1 on success
+ * \retval 0 revalidation from statahead cache failed, caller needs
+ * to getattr from server directly
+ * \retval negative number on error, caller often ignores this and
+ * then getattr from server
+ */
+int ll_statahead(struct inode *dir, struct dentry **dentryp, bool unplug)
+{
+ struct ll_statahead_info *sai;
+
+ sai = ll_sai_get(dir);
+ if (sai) {
+ int rc;
+
+ rc = revalidate_statahead_dentry(dir, sai, dentryp, unplug);
+ CDEBUG(D_READA, "revalidate statahead %pd: %d.\n",
+ *dentryp, rc);
+ ll_sai_put(sai);
+ return rc;
+ }
+ return start_statahead_thread(dir, *dentryp);
+}
generated by cgit v1.2.3 (git 2.0.4) at 2024-06-12 05:30:20 +0000