From mboxrd@z Thu Jan  1 00:00:00 1970
From: Oleg Nesterov <oleg-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
Subject: Re: cgroup attach task - slogging cpu
Date: Wed, 9 Oct 2013 16:05:51 +0200
Message-ID: <20131009140551.GA15849@redhat.com>
References: <CALPf4Tz+Gf_Q7wKKBufCc1mtV1qVPVrOW0S1qhHxfOv6pJa2Kg@mail.gmail.com> <20131004130207.GA9338@redhat.com> <20131007184507.GD27396@htj.dyndns.org> <20131008145833.GA15600@redhat.com> <5254EB2A.7090803@huawei.com> <20131009133047.GA12414@redhat.com>
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To: Li Zefan <lizefan-hv44wF8Li93QT0dZR+AlfA@public.gmane.org>
Cc: Tejun Heo <tj-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>, anjana vk <anjanvk12-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>, cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org

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.