posix-timers: Remove dead task special case (a3222f88) · Commits · 戴 / test

kernel/posix-cpu-timers.c

+25 −45

Original line number	Diff line number	Diff line
		@@ -374,7 +374,8 @@ static int posix_cpu_timer_del(struct k_itimer *timer)
		struct task_struct *p = timer->it.cpu.task;
		int ret = 0;

		if (likely(p != NULL)) {
		WARN_ON_ONCE(p == NULL);

		read_lock(&tasklist_lock);
		if (unlikely(p->sighand == NULL)) {
		/*
		@@ -394,7 +395,6 @@ static int posix_cpu_timer_del(struct k_itimer *timer)

		if (!ret)
		put_task_struct(p);
		}

		return ret;
		}
		@@ -622,12 +622,7 @@ static int posix_cpu_timer_set(struct k_itimer *timer, int flags,
		unsigned long long old_expires, new_expires, old_incr, val;
		int ret;

		if (unlikely(p == NULL)) {
		/*
		* Timer refers to a dead task's clock.
		*/
		return -ESRCH;
		}
		WARN_ON_ONCE(p == NULL);

		new_expires = timespec_to_sample(timer->it_clock, &new->it_value);

		@@ -770,6 +765,8 @@ static void posix_cpu_timer_get(struct k_itimer timer, struct itimerspec itp)
		unsigned long long now;
		struct task_struct *p = timer->it.cpu.task;

		WARN_ON_ONCE(p == NULL);

		/*
		* Easy part: convert the reload time.
		*/
		@@ -781,18 +778,6 @@ static void posix_cpu_timer_get(struct k_itimer timer, struct itimerspec itp)
		return;
		}

		if (unlikely(p == NULL)) {
		WARN_ON_ONCE(CPUCLOCK_PERTHREAD(timer->it_clock));
		/*
		* This task already died and the timer will never fire.
		* In this case, expires is actually the dead value.
		*/
		dead:
		sample_to_timespec(timer->it_clock, timer->it.cpu.expires,
		&itp->it_value);
		return;
		}

		/*
		* Sample the clock to take the difference with the expiry time.
		*/
		@@ -807,8 +792,9 @@ static void posix_cpu_timer_get(struct k_itimer timer, struct itimerspec itp)
		* Call the timer disarmed, nothing else to do.
		*/
		timer->it.cpu.expires = 0;
		sample_to_timespec(timer->it_clock, timer->it.cpu.expires,
		&itp->it_value);
		read_unlock(&tasklist_lock);
		goto dead;
		} else {
		cpu_timer_sample_group(timer->it_clock, p, &now);
		}
		@@ -1029,13 +1015,7 @@ void posix_cpu_timer_schedule(struct k_itimer *timer)
		struct task_struct *p = timer->it.cpu.task;
		unsigned long long now;

		if (unlikely(p == NULL)) {
		WARN_ON_ONCE(CPUCLOCK_PERTHREAD(timer->it_clock));
		/*
		* The task was cleaned up already, no future firings.
		*/
		goto out;
		}
		WARN_ON_ONCE(p == NULL);

		/*
		* Fetch the current sample and update the timer's expiry time.

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