summaryrefslogtreecommitdiff
path: root/kernel/time
diff options
context:
space:
mode:
Diffstat (limited to 'kernel/time')
-rw-r--r--kernel/time/hrtimer.c12
-rw-r--r--kernel/time/posix-timers.c34
-rw-r--r--kernel/time/tick-sched.c19
-rw-r--r--kernel/time/timer.c9
4 files changed, 54 insertions, 20 deletions
diff --git a/kernel/time/hrtimer.c b/kernel/time/hrtimer.c
index 17f7bcff1e02..8c4e27cbfe7f 100644
--- a/kernel/time/hrtimer.c
+++ b/kernel/time/hrtimer.c
@@ -312,7 +312,7 @@ EXPORT_SYMBOL_GPL(__ktime_divns);
*/
ktime_t ktime_add_safe(const ktime_t lhs, const ktime_t rhs)
{
- ktime_t res = ktime_add(lhs, rhs);
+ ktime_t res = ktime_add_unsafe(lhs, rhs);
/*
* We use KTIME_SEC_MAX here, the maximum timeout which we can
@@ -669,7 +669,9 @@ static void hrtimer_reprogram(struct hrtimer *timer,
static inline void hrtimer_init_hres(struct hrtimer_cpu_base *base)
{
base->expires_next.tv64 = KTIME_MAX;
+ base->hang_detected = 0;
base->hres_active = 0;
+ base->next_timer = NULL;
}
/*
@@ -1137,7 +1139,12 @@ static void __hrtimer_init(struct hrtimer *timer, clockid_t clock_id,
cpu_base = raw_cpu_ptr(&hrtimer_bases);
- if (clock_id == CLOCK_REALTIME && mode != HRTIMER_MODE_ABS)
+ /*
+ * POSIX magic: Relative CLOCK_REALTIME timers are not affected by
+ * clock modifications, so they needs to become CLOCK_MONOTONIC to
+ * ensure POSIX compliance.
+ */
+ if (clock_id == CLOCK_REALTIME && mode & HRTIMER_MODE_REL)
clock_id = CLOCK_MONOTONIC;
base = hrtimer_clockid_to_base(clock_id);
@@ -1615,6 +1622,7 @@ static void init_hrtimers_cpu(int cpu)
timerqueue_init_head(&cpu_base->clock_base[i].active);
}
+ cpu_base->active_bases = 0;
cpu_base->cpu = cpu;
hrtimer_init_hres(cpu_base);
}
diff --git a/kernel/time/posix-timers.c b/kernel/time/posix-timers.c
index f2826c35e918..fc7c37ad90a0 100644
--- a/kernel/time/posix-timers.c
+++ b/kernel/time/posix-timers.c
@@ -507,17 +507,22 @@ static struct pid *good_sigevent(sigevent_t * event)
{
struct task_struct *rtn = current->group_leader;
- if ((event->sigev_notify & SIGEV_THREAD_ID ) &&
- (!(rtn = find_task_by_vpid(event->sigev_notify_thread_id)) ||
- !same_thread_group(rtn, current) ||
- (event->sigev_notify & ~SIGEV_THREAD_ID) != SIGEV_SIGNAL))
+ switch (event->sigev_notify) {
+ case SIGEV_SIGNAL | SIGEV_THREAD_ID:
+ rtn = find_task_by_vpid(event->sigev_notify_thread_id);
+ if (!rtn || !same_thread_group(rtn, current))
+ return NULL;
+ /* FALLTHRU */
+ case SIGEV_SIGNAL:
+ case SIGEV_THREAD:
+ if (event->sigev_signo <= 0 || event->sigev_signo > SIGRTMAX)
+ return NULL;
+ /* FALLTHRU */
+ case SIGEV_NONE:
+ return task_pid(rtn);
+ default:
return NULL;
-
- if (((event->sigev_notify & ~SIGEV_THREAD_ID) != SIGEV_NONE) &&
- ((event->sigev_signo <= 0) || (event->sigev_signo > SIGRTMAX)))
- return NULL;
-
- return task_pid(rtn);
+ }
}
void posix_timers_register_clock(const clockid_t clock_id,
@@ -745,8 +750,7 @@ common_timer_get(struct k_itimer *timr, struct itimerspec *cur_setting)
/* interval timer ? */
if (iv.tv64)
cur_setting->it_interval = ktime_to_timespec(iv);
- else if (!hrtimer_active(timer) &&
- (timr->it_sigev_notify & ~SIGEV_THREAD_ID) != SIGEV_NONE)
+ else if (!hrtimer_active(timer) && timr->it_sigev_notify != SIGEV_NONE)
return;
now = timer->base->get_time();
@@ -757,7 +761,7 @@ common_timer_get(struct k_itimer *timr, struct itimerspec *cur_setting)
* expiry is > now.
*/
if (iv.tv64 && (timr->it_requeue_pending & REQUEUE_PENDING ||
- (timr->it_sigev_notify & ~SIGEV_THREAD_ID) == SIGEV_NONE))
+ timr->it_sigev_notify == SIGEV_NONE))
timr->it_overrun += (unsigned int) hrtimer_forward(timer, now, iv);
remaining = __hrtimer_expires_remaining_adjusted(timer, now);
@@ -767,7 +771,7 @@ common_timer_get(struct k_itimer *timr, struct itimerspec *cur_setting)
* A single shot SIGEV_NONE timer must return 0, when
* it is expired !
*/
- if ((timr->it_sigev_notify & ~SIGEV_THREAD_ID) != SIGEV_NONE)
+ if (timr->it_sigev_notify != SIGEV_NONE)
cur_setting->it_value.tv_nsec = 1;
} else
cur_setting->it_value = ktime_to_timespec(remaining);
@@ -865,7 +869,7 @@ common_timer_set(struct k_itimer *timr, int flags,
timr->it.real.interval = timespec_to_ktime(new_setting->it_interval);
/* SIGEV_NONE timers are not queued ! See common_timer_get */
- if (((timr->it_sigev_notify & ~SIGEV_THREAD_ID) == SIGEV_NONE)) {
+ if (timr->it_sigev_notify == SIGEV_NONE) {
/* Setup correct expiry time for relative timers */
if (mode == HRTIMER_MODE_REL) {
hrtimer_add_expires(timer, timer->base->get_time());
diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c
index 22c57e191a23..e5d228f7224c 100644
--- a/kernel/time/tick-sched.c
+++ b/kernel/time/tick-sched.c
@@ -568,6 +568,11 @@ static void tick_nohz_restart(struct tick_sched *ts, ktime_t now)
tick_program_event(hrtimer_get_expires(&ts->sched_timer), 1);
}
+static inline bool local_timer_softirq_pending(void)
+{
+ return local_softirq_pending() & TIMER_SOFTIRQ;
+}
+
static ktime_t tick_nohz_stop_sched_tick(struct tick_sched *ts,
ktime_t now, int cpu)
{
@@ -584,8 +589,18 @@ static ktime_t tick_nohz_stop_sched_tick(struct tick_sched *ts,
} while (read_seqretry(&jiffies_lock, seq));
ts->last_jiffies = basejiff;
- if (rcu_needs_cpu(basemono, &next_rcu) ||
- arch_needs_cpu() || irq_work_needs_cpu()) {
+ /*
+ * Keep the periodic tick, when RCU, architecture or irq_work
+ * requests it.
+ * Aside of that check whether the local timer softirq is
+ * pending. If so its a bad idea to call get_next_timer_interrupt()
+ * because there is an already expired timer, so it will request
+ * immeditate expiry, which rearms the hardware timer with a
+ * minimal delta which brings us back to this place
+ * immediately. Lather, rinse and repeat...
+ */
+ if (rcu_needs_cpu(basemono, &next_rcu) || arch_needs_cpu() ||
+ irq_work_needs_cpu() || local_timer_softirq_pending()) {
next_tick = basemono + TICK_NSEC;
} else {
/*
diff --git a/kernel/time/timer.c b/kernel/time/timer.c
index 125407144c01..3d7588a2e97c 100644
--- a/kernel/time/timer.c
+++ b/kernel/time/timer.c
@@ -764,8 +764,15 @@ static struct tvec_base *lock_timer_base(struct timer_list *timer,
__acquires(timer->base->lock)
{
for (;;) {
- u32 tf = timer->flags;
struct tvec_base *base;
+ u32 tf;
+
+ /*
+ * We need to use READ_ONCE() here, otherwise the compiler
+ * might re-read @tf between the check for TIMER_MIGRATING
+ * and spin_lock().
+ */
+ tf = READ_ONCE(timer->flags);
if (!(tf & TIMER_MIGRATING)) {
base = per_cpu_ptr(&tvec_bases, tf & TIMER_CPUMASK);
generated by cgit v1.2.3 (git 2.0.4) at 2024-05-10 03:56:51 +0000