diff options
Diffstat (limited to 'kernel/time/posix-timers.c')
| -rw-r--r-- | kernel/time/posix-timers.c | 43 |
1 files changed, 40 insertions, 3 deletions
diff --git a/kernel/time/posix-timers.c b/kernel/time/posix-timers.c index 708992708332..c5866984f12d 100644 --- a/kernel/time/posix-timers.c +++ b/kernel/time/posix-timers.c @@ -434,6 +434,7 @@ static enum hrtimer_restart posix_timer_fn(struct hrtimer *timer) static struct pid *good_sigevent(sigevent_t * event) { struct task_struct *rtn = current->group_leader; + int sig = event->sigev_signo; switch (event->sigev_notify) { case SIGEV_SIGNAL | SIGEV_THREAD_ID: @@ -443,7 +444,8 @@ static struct pid *good_sigevent(sigevent_t * event) /* FALLTHRU */ case SIGEV_SIGNAL: case SIGEV_THREAD: - if (event->sigev_signo <= 0 || event->sigev_signo > SIGRTMAX) + if (sig <= 0 || sig > SIGRTMAX || + sig_kernel_only(sig) || sig_kernel_coredump(sig)) return NULL; /* FALLTHRU */ case SIGEV_NONE: @@ -469,7 +471,7 @@ static struct k_itimer * alloc_posix_timer(void) static void k_itimer_rcu_free(struct rcu_head *head) { - struct k_itimer *tmr = container_of(head, struct k_itimer, it.rcu); + struct k_itimer *tmr = container_of(head, struct k_itimer, rcu); kmem_cache_free(posix_timers_cache, tmr); } @@ -486,7 +488,7 @@ static void release_posix_timer(struct k_itimer *tmr, int it_id_set) } put_pid(tmr->it_pid); sigqueue_free(tmr->sigq); - call_rcu(&tmr->it.rcu, k_itimer_rcu_free); + call_rcu(&tmr->rcu, k_itimer_rcu_free); } static int common_timer_create(struct k_itimer *new_timer) @@ -825,6 +827,22 @@ 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) +{ +#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 +} + static int common_hrtimer_try_to_cancel(struct k_itimer *timr) { return hrtimer_try_to_cancel(&timr->it.real.timer); @@ -889,6 +907,7 @@ retry: if (!timr) return -EINVAL; + rcu_read_lock(); kc = timr->kclock; if (WARN_ON_ONCE(!kc || !kc->timer_set)) error = -EINVAL; @@ -897,9 +916,12 @@ retry: unlock_timer(timr, flag); if (error == TIMER_RETRY) { + timer_wait_for_callback(kc, timr); old_spec64 = NULL; // We already got the old time... + rcu_read_unlock(); goto retry; } + rcu_read_unlock(); return error; } @@ -981,10 +1003,15 @@ 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(); goto retry_delete; } + rcu_read_unlock(); spin_lock(¤t->sighand->siglock); list_del(&timer->list); @@ -1010,8 +1037,18 @@ 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(); goto retry_delete; } list_del(&timer->list); |