diff options
Diffstat (limited to 'kernel/time/posix-timers.c')
| -rw-r--r-- | kernel/time/posix-timers.c | 69 |
1 files changed, 27 insertions, 42 deletions
diff --git a/kernel/time/posix-timers.c b/kernel/time/posix-timers.c index a5ec421e3437..c7e97d421590 100644 --- a/kernel/time/posix-timers.c +++ b/kernel/time/posix-timers.c @@ -821,25 +821,20 @@ static void common_hrtimer_arm(struct k_itimer *timr, ktime_t expires, hrtimer_start_expires(timer, HRTIMER_MODE_ABS); } -/* - * Protected by RCU! - */ -static void timer_wait_for_callback(const struct k_clock *kc, struct k_itimer *timr) +static int common_hrtimer_try_to_cancel(struct k_itimer *timr) { -#ifdef CONFIG_PREEMPT_RT_FULL - if (kc->timer_arm == common_hrtimer_arm) - hrtimer_wait_for_timer(&timr->it.real.timer); - else if (kc == &alarm_clock) - hrtimer_wait_for_timer(&timr->it.alarm.alarmtimer.timer); - else - /* FIXME: Whacky hack for posix-cpu-timers */ - schedule_timeout(1); -#endif + return hrtimer_try_to_cancel(&timr->it.real.timer); } -static int common_hrtimer_try_to_cancel(struct k_itimer *timr) +static void timer_wait_for_callback(const struct k_clock *kc, struct k_itimer *timer) { - return hrtimer_try_to_cancel(&timr->it.real.timer); + if (kc->timer_arm == common_hrtimer_arm) + hrtimer_grab_expiry_lock(&timer->it.real.timer); + else if (kc == &alarm_clock) + hrtimer_grab_expiry_lock(&timer->it.alarm.alarmtimer.timer); + else + /* posix-cpu-timers */ + cpu_timers_grab_expiry_lock(timer); } /* Set a POSIX.1b interval timer. */ @@ -901,21 +896,21 @@ retry: if (!timr) return -EINVAL; - rcu_read_lock(); kc = timr->kclock; if (WARN_ON_ONCE(!kc || !kc->timer_set)) error = -EINVAL; else error = kc->timer_set(timr, flags, new_spec64, old_spec64); - unlock_timer(timr, flag); if (error == TIMER_RETRY) { + rcu_read_lock(); + unlock_timer(timr, flag); timer_wait_for_callback(kc, timr); - old_spec64 = NULL; // We already got the old time... rcu_read_unlock(); + old_spec64 = NULL; // We already got the old time... goto retry; } - rcu_read_unlock(); + unlock_timer(timr, flag); return error; } @@ -977,13 +972,21 @@ int common_timer_del(struct k_itimer *timer) return 0; } -static inline int timer_delete_hook(struct k_itimer *timer) +static int timer_delete_hook(struct k_itimer *timer) { const struct k_clock *kc = timer->kclock; + int ret; if (WARN_ON_ONCE(!kc || !kc->timer_del)) return -EINVAL; - return kc->timer_del(timer); + ret = kc->timer_del(timer); + if (ret == TIMER_RETRY) { + rcu_read_lock(); + spin_unlock_irq(&timer->it_lock); + timer_wait_for_callback(kc, timer); + rcu_read_unlock(); + } + return ret; } /* Delete a POSIX.1b interval timer. */ @@ -997,15 +1000,8 @@ retry_delete: if (!timer) return -EINVAL; - rcu_read_lock(); - if (timer_delete_hook(timer) == TIMER_RETRY) { - unlock_timer(timer, flags); - timer_wait_for_callback(clockid_to_kclock(timer->it_clock), - timer); - rcu_read_unlock(); + if (timer_delete_hook(timer) == TIMER_RETRY) goto retry_delete; - } - rcu_read_unlock(); spin_lock(¤t->sighand->siglock); list_del(&timer->list); @@ -1031,20 +1027,9 @@ static void itimer_delete(struct k_itimer *timer) retry_delete: spin_lock_irqsave(&timer->it_lock, flags); - /* On RT we can race with a deletion */ - if (!timer->it_signal) { - unlock_timer(timer, flags); - return; - } - - if (timer_delete_hook(timer) == TIMER_RETRY) { - rcu_read_lock(); - unlock_timer(timer, flags); - timer_wait_for_callback(clockid_to_kclock(timer->it_clock), - timer); - rcu_read_unlock(); + if (timer_delete_hook(timer) == TIMER_RETRY) goto retry_delete; - } + list_del(&timer->list); /* * This keeps any tasks waiting on the spin lock from thinking |