lkml.org 
[lkml]   [2011]   [Feb]   [2]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: [PATCH 1/2] perf_events: add cgroup support (v8)
From
Date
On Thu, 2011-01-20 at 15:39 +0100, Peter Zijlstra wrote:
> On Thu, 2011-01-20 at 15:30 +0200, Stephane Eranian wrote:
> > @@ -4259,8 +4261,20 @@ void cgroup_exit(struct task_struct *tsk, int run_callbacks)
> >
> > /* Reassign the task to the init_css_set. */
> > task_lock(tsk);
> > + /*
> > + * we mask interrupts to prevent:
> > + * - timer tick to cause event rotation which
> > + * could schedule back in cgroup events after
> > + * they were switched out by perf_cgroup_sched_out()
> > + *
> > + * - preemption which could schedule back in cgroup events
> > + */
> > + local_irq_save(flags);
> > + perf_cgroup_sched_out(tsk);
> > cg = tsk->cgroups;
> > tsk->cgroups = &init_css_set;
> > + perf_cgroup_sched_in(tsk);
> > + local_irq_restore(flags);
> > task_unlock(tsk);
> > if (cg)
> > put_css_set_taskexit(cg);
>
> So you too need a callback on cgroup change there.. Li, Paul, any chance
> we can fix this cgroup_subsys::exit callback? The scheduler code needs
> to do funny thing because its in the wrong place as well.

cgroup guys? Shall I just fix this exit thing since the only user seems
to be the scheduler and now perf for both of which its unfortunate at
best?

Balbir, memcontrol.c uses pre_destroy(), I pose that using this method
is broken per definition since it makes the cgroup empty notification
void.





\
 
 \ /
  Last update: 2011-02-02 12:31    [W:0.066 / U:8.972 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site