diff options
| -rw-r--r-- | kernel/posix-cpu-timers.c | 34 |
1 files changed, 16 insertions, 18 deletions
diff --git a/kernel/posix-cpu-timers.c b/kernel/posix-cpu-timers.c index 79747b7d9420..3b7df8653913 100644 --- a/kernel/posix-cpu-timers.c +++ b/kernel/posix-cpu-timers.c @@ -788,7 +788,6 @@ 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; - int clear_dead; /* * Easy part: convert the reload time. @@ -802,6 +801,7 @@ static void posix_cpu_timer_get(struct k_itimer *timer, struct itimerspec *itp) } 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. @@ -817,7 +817,6 @@ static void posix_cpu_timer_get(struct k_itimer *timer, struct itimerspec *itp) */ if (CPUCLOCK_PERTHREAD(timer->it_clock)) { cpu_clock_sample(timer->it_clock, p, &now); - clear_dead = p->exit_state; } else { read_lock(&tasklist_lock); if (unlikely(p->sighand == NULL)) { @@ -833,22 +832,20 @@ static void posix_cpu_timer_get(struct k_itimer *timer, struct itimerspec *itp) goto dead; } else { cpu_timer_sample_group(timer->it_clock, p, &now); - clear_dead = (unlikely(p->exit_state) && - thread_group_empty(p)); + if (unlikely(p->exit_state) && thread_group_empty(p)) { + read_unlock(&tasklist_lock); + /* + * We've noticed that the thread is dead, but + * not yet reaped. Take this opportunity to + * drop our task ref. + */ + clear_dead_task(timer, now); + goto dead; + } } read_unlock(&tasklist_lock); } - if (unlikely(clear_dead)) { - /* - * We've noticed that the thread is dead, but - * not yet reaped. Take this opportunity to - * drop our task ref. - */ - clear_dead_task(timer, now); - goto dead; - } - if (now < timer->it.cpu.expires) { sample_to_timespec(timer->it_clock, timer->it.cpu.expires - now, @@ -1063,11 +1060,13 @@ 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)) + if (unlikely(p == NULL)) { + WARN_ON_ONCE(CPUCLOCK_PERTHREAD(timer->it_clock)); /* * The task was cleaned up already, no future firings. */ goto out; + } /* * Fetch the current sample and update the timer's expiry time. @@ -1075,10 +1074,9 @@ void posix_cpu_timer_schedule(struct k_itimer *timer) if (CPUCLOCK_PERTHREAD(timer->it_clock)) { cpu_clock_sample(timer->it_clock, p, &now); bump_cpu_timer(timer, now); - if (unlikely(p->exit_state)) { - clear_dead_task(timer, now); + if (unlikely(p->exit_state)) goto out; - } + read_lock(&tasklist_lock); /* arm_timer needs it. */ spin_lock(&p->sighand->siglock); } else { |