[PATCH 03/10] posix-timers: Cleanup reaped target handling

From: Frederic Weisbecker
Date: Sat Nov 23 2013 - 10:37:38 EST


When a timer's target is seen to be buried, for example on calls
to timer_gettime(), the posix cpu timers code behaves a bit
like a garbage collector and releases early the reference to the
task.

Then again, this optimization complicates the code for no much
value: it's up to the user to release the timer and its associated
ressources by calling timer_delete() after it buries the target
tasks.

Remove this to simplify the code.

Signed-off-by: Frederic Weisbecker <fweisbec@xxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Oleg Nesterov <oleg@xxxxxxxxxx>
Cc: Kosaki Motohiro <kosaki.motohiro@xxxxxxxxxxxxxx>
Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
kernel/posix-cpu-timers.c | 6 ------
1 file changed, 6 deletions(-)

diff --git a/kernel/posix-cpu-timers.c b/kernel/posix-cpu-timers.c
index dd75dc4..f509f53 100644
--- a/kernel/posix-cpu-timers.c
+++ b/kernel/posix-cpu-timers.c
@@ -638,8 +638,6 @@ static int posix_cpu_timer_set(struct k_itimer *timer, int flags,
*/
if (unlikely(p->sighand == NULL)) {
read_unlock(&tasklist_lock);
- put_task_struct(p);
- timer->it.cpu.task = NULL;
return -ESRCH;
}

@@ -807,8 +805,6 @@ static void posix_cpu_timer_get(struct k_itimer *timer, struct itimerspec *itp)
* We can't even collect a sample any more.
* Call the timer disarmed, nothing else to do.
*/
- put_task_struct(p);
- timer->it.cpu.task = NULL;
timer->it.cpu.expires = 0;
read_unlock(&tasklist_lock);
goto dead;
@@ -1058,8 +1054,6 @@ void posix_cpu_timer_schedule(struct k_itimer *timer)
* The process has been reaped.
* We can't even collect a sample any more.
*/
- put_task_struct(p);
- timer->it.cpu.task = p = NULL;
timer->it.cpu.expires = 0;
goto out_unlock;
} else if (unlikely(p->exit_state) && thread_group_empty(p)) {
--
1.8.3.1

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