[PATCH] cgroup: remove redundate get/put of old css_set from migrate

[Tejun Heo]

On Fri, Dec 16, 2011 at 08:38:31AM -0800, Mandeep Singh Baines wrote:
> We can now assume that the css_set reference held by the task
> will not go away for an exiting task. PF_EXITING state can be
> trusted throughout migration by checking it after locking
> threadgroup.
> 
> This patch depends on:
> 
> commit cd3d095275374220921fcf0d4e0c16584b26ddbc
> Author: Tejun Heo <tj at kernel.org>
> Date:   Mon Dec 12 18:12:21 2011 -0800
> 
>     cgroup: always lock threadgroup during migration
> 
> Signed-off-by: Mandeep Singh Baines <msb at chromium.org>
> Cc: Tejun Heo <tj at kernel.org>
> Cc: Li Zefan <lizf at cn.fujitsu.com>
> Cc: containers at lists.linux-foundation.org
> Cc: cgroups at vger.kernel.org
> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu at jp.fujitsu.com>
> Cc: Frederic Weisbecker <fweisbec at gmail.com>
> Cc: Oleg Nesterov <oleg at redhat.com>
> Cc: Andrew Morton <akpm at linux-foundation.org>
> Cc: Paul Menage <paul at paulmenage.org>

Li, can you please ack this?

Thanks.

-- 
tejun