Re: [PATCH 02/10] posix-timers: Remove dead process posix cpu timers caching

2013-12-04 Thread Frederic Weisbecker 
On Wed, Dec 04, 2013 at 01:50:34PM -0500, KOSAKI Motohiro wrote:
> > @@ -1090,13 +1063,8 @@ void posix_cpu_timer_schedule(struct k_itimer *timer)
> > timer->it.cpu.expires = 0;
> > goto out_unlock;
> > } else if (unlikely(p->exit_state) && thread_group_empty(p)) {
> > -   /*
> > -* We've noticed that the thread is dead, but
> > -* not yet reaped.  Take this opportunity to
> > -* drop our task ref.
> > -*/
> > +   /* Optimizations: if the process is dying, no need to 
> > rearm */
> > cpu_timer_sample_group(timer->it_clock, p, &now);
> 
> Why do we still need to call cpu_timer_sample_group? You removed to below 
> line which uses
> "now".

Good point, it looks safe to remove it now.

Thanks.
 
> > -   clear_dead_task(timer, now);
> > goto out_unlock;
> > }
> > spin_lock(&p->sighand->siglock);
> > 
> 
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Re: [PATCH 02/10] posix-timers: Remove dead process posix cpu timers caching

2013-12-04 Thread KOSAKI Motohiro 
> @@ -1090,13 +1063,8 @@ void posix_cpu_timer_schedule(struct k_itimer *timer)
>   timer->it.cpu.expires = 0;
>   goto out_unlock;
>   } else if (unlikely(p->exit_state) && thread_group_empty(p)) {
> - /*
> -  * We've noticed that the thread is dead, but
> -  * not yet reaped.  Take this opportunity to
> -  * drop our task ref.
> -  */
> + /* Optimizations: if the process is dying, no need to 
> rearm */
>   cpu_timer_sample_group(timer->it_clock, p, &now);

Why do we still need to call cpu_timer_sample_group? You removed to below line 
which uses
"now".

> - clear_dead_task(timer, now);
>   goto out_unlock;
>   }
>   spin_lock(&p->sighand->siglock);
> 

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