posix-timers: Rework cancel retry loops (6945e5c2) · Commits · 戴 / test

kernel/time/posix-timers.c

+23 −6

Original line number	Original line	Diff line number	Diff line
	@@ -805,6 +805,17 @@ static int common_hrtimer_try_to_cancel(struct k_itimer *timr)
	return hrtimer_try_to_cancel(&timr->it.real.timer);		return hrtimer_try_to_cancel(&timr->it.real.timer);
	}		}

			static struct k_itimer timer_wait_running(struct k_itimer timer,
			unsigned long *flags)
			{
			timer_t timer_id = READ_ONCE(timer->it_id);

			unlock_timer(timer, *flags);
			cpu_relax();
			/* Relock the timer. It might be not longer hashed. */
			return lock_timer(timer_id, flags);
			}

	/* Set a POSIX.1b interval timer. */		/* Set a POSIX.1b interval timer. */
	int common_timer_set(struct k_itimer *timr, int flags,		int common_timer_set(struct k_itimer *timr, int flags,
	struct itimerspec64 *new_setting,		struct itimerspec64 *new_setting,
	@@ -859,8 +870,9 @@ static int do_timer_settime(timer_t timer_id, int tmr_flags,

	if (old_spec64)		if (old_spec64)
	memset(old_spec64, 0, sizeof(*old_spec64));		memset(old_spec64, 0, sizeof(*old_spec64));
	retry:
	timr = lock_timer(timer_id, &flags);		timr = lock_timer(timer_id, &flags);
			retry:
	if (!timr)		if (!timr)
	return -EINVAL;		return -EINVAL;

	@@ -870,11 +882,14 @@ retry:
	else		else
	error = kc->timer_set(timr, tmr_flags, new_spec64, old_spec64);		error = kc->timer_set(timr, tmr_flags, new_spec64, old_spec64);

	unlock_timer(timr, flags);
	if (error == TIMER_RETRY) {		if (error == TIMER_RETRY) {
	old_spec64 = NULL; // We already got the old time...		// We already got the old time...
			old_spec64 = NULL;
			/* Unlocks and relocks the timer if it still exists */
			timr = timer_wait_running(timr, &flags);
	goto retry;		goto retry;
	}		}
			unlock_timer(timr, flags);

	return error;		return error;
	}		}
	@@ -951,13 +966,15 @@ SYSCALL_DEFINE1(timer_delete, timer_t, timer_id)
	struct k_itimer *timer;		struct k_itimer *timer;
	unsigned long flags;		unsigned long flags;

	retry_delete:
	timer = lock_timer(timer_id, &flags);		timer = lock_timer(timer_id, &flags);

			retry_delete:
	if (!timer)		if (!timer)
	return -EINVAL;		return -EINVAL;

	if (timer_delete_hook(timer) == TIMER_RETRY) {		if (unlikely(timer_delete_hook(timer) == TIMER_RETRY)) {
	unlock_timer(timer, flags);		/* Unlocks and relocks the timer if it still exists */
			timer = timer_wait_running(timer, &flags);
	goto retry_delete;		goto retry_delete;
	}		}

Admin message