[PATCH 3/5] cgroup: only need to check oldcgrp==newgrp once

[Li Zefan]

Mandeep Singh Baines wrote:
> In cgroup_attach_proc it is now sufficient to only check that
> oldcgrp==newcgrp once. Now that we are using threadgroup_lock()
> during the migrations, oldcgrp will not change.
> 
> Signed-off-by: Mandeep Singh Baines <msb at chromium.org>

Reviewed-by: Li Zefan <lizf at cn.fujitsu.com>

> 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>
> ---
>  kernel/cgroup.c |   17 ++++++-----------
>  1 files changed, 6 insertions(+), 11 deletions(-)