From mboxrd@z Thu Jan  1 00:00:00 1970
From: Tejun Heo <tj-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
Subject: Re: [PATCH 1/2] cgroup: Remove unnecessary task_lock before
	fetching css_set on migration
Date: Tue, 20 Dec 2011 11:14:43 -0800
Message-ID: <20111220191443.GE10752@google.com>
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To: Frederic Weisbecker <fweisbec-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
Cc: Containers <containers-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org>, LKML <linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org>, Oleg Nesterov <oleg-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>, Mandeep Singh Baines <msb-F7+t8E8rja9g9hUCZPvPmw@public.gmane.org>, Cgroups <cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org>, Andrew Morton <akpm-de/tnXTf+JLsfHDXvbKv3WD2FQJk+8+b@public.gmane.org>, Paul Menage <paul-inf54ven1CmVyaH7bEyXVA@public.gmane.org>

Hello, Frederic.

On Tue, Dec 20, 2011 at 08:01:12PM +0100, Frederic Weisbecker wrote:
> When we fetch the css_set of the tasks on cgroup migration, we don't need
> anymore to synchronize against cgroup_exit() that could swap the old one
> with init_css_set. Now that we are using threadgroup_lock() during
> the migrations, we don't need to worry about it anymore.
> 
> Signed-off-by: Frederic Weisbecker <fweisbec-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
> Cc: Tejun Heo <tj-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
> Cc: Li Zefan <lizf-BthXqXjhjHXQFUHtdCDX3A@public.gmane.org>
> Cc: Containers <containers-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org>
> Cc: Cgroups <cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org>
> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu-+CUm20s59erQFUHtdCDX3A@public.gmane.org>
> Cc: Oleg Nesterov <oleg-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
> Cc: Andrew Morton <akpm-de/tnXTf+JLsfHDXvbKv3WD2FQJk+8+b@public.gmane.org>
> Cc: Paul Menage <paul-inf54ven1CmVyaH7bEyXVA@public.gmane.org>
> Cc: Mandeep Singh Baines <msb-F7+t8E8rja9g9hUCZPvPmw@public.gmane.org>

I like this but it doesn't apply on top of cgroup/for-3.3.  It
collides with Mandeep's patch.  Can you please rebase?

Li, can you please ack?

Thanks.

-- 
tejun