From mboxrd@z Thu Jan  1 00:00:00 1970
From: anjana vk <anjanvk12-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
Subject: Re: cgroup attach task - slogging cpu
Date: Thu, 10 Oct 2013 09:52:00 +0530
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To: Anjana V Kumar <anjanavk12-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
Cc: Oleg Nesterov <oleg-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>, Li Zefan <lizefan-hv44wF8Li93QT0dZR+AlfA@public.gmane.org>, Tejun Heo <tj-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>, cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, stable-u79uwXL29TY76Z2rM5mHXA@public.gmane.org

+cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org

On 10/10/13, Anjana V Kumar <anjanavk12-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote:
> Hi All,
>
> Please find the attached patch making the changes for the case where thread
> is already in the required cgroup.
>
> Can you please let me know if this is the right way to fix this issue, if
> any modifications are required.
>
> Thanks and Regards
> Anjana
>
>
> On Wed, Oct 9, 2013 at 7:35 PM, Oleg Nesterov <oleg-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org> wrote:
>
>> On 10/09, Oleg Nesterov wrote:
>> >
>> > On 10/09, Li Zefan wrote:
>> > >
>> > > Anjana, could you revise the patch and send it out with proper
>> changelog
>> > > and Signed-off-by? And please add "Cc: <stable-u79uwXL29TY76Z2rM5mHXA@public.gmane.org> #
>> 3.9+"
>> >
>> > Yes, Anjana, please!
>>
>> Please note also that the PF_EXITING check has the same problem, it also
>> needs "goto next".
>>
>> > > > check in the main loop. So Anjana was right (sorry again!), and we
>> > > > should probably do
>> > > >
>> > > >           ent.cgrp = task_cgroup_from_root(...);
>> > > >           if (ent.cgrp != cgrp) {
>> > > >                   retval = flex_array_put(...);
>> > > >                   ...
>> > > >           }
>> > > >
>> > > >           if (!threadgroup)
>> > > >                   break;
>> > > >
>> > >
>> > > Or
>> > >
>> > > do {
>> > >     ...
>> > >     if (ent.cgrp == cgrp)
>> > >             goto next;
>> >
>> > Or this, agreed.
>> >
>> > > > Or I am wrong again?
>> > >
>> > > No, you are not! :)
>> >
>> > Thanks ;)
>> >
>> > Oleg.
>>
>>
>
>
> --
> Anjana
>