[PATCH 2/3] cgroup: replace tasklist_lock with rcu_read_lock

[Li Zefan]

Mandeep Singh Baines wrote:
> We can replace the tasklist_lock in cgroup_attach_proc with an
> rcu_read_lock.
> 
> Changes in V4:
> * https://lkml.org/lkml/2011/12/23/284 (Frederic Weisbecker)
>   * Minimize size of rcu_read_lock critical section
>   * Add comment
> * https://lkml.org/lkml/2011/12/26/136 (Li Zefan)
>   * Split into two patches
> Changes in V3:
> * https://lkml.org/lkml/2011/12/22/419 (Frederic Weisbecker)
>   * Add an rcu_read_lock to protect against exit
> Changes in V2:
> * https://lkml.org/lkml/2011/12/22/86 (Tejun Heo)
>   * Use a goto instead of returning -EAGAIN
> 
> Suggested-by: Frederic Weisbecker <fweisbec at gmail.com>
> Signed-off-by: Mandeep Singh Baines <msb at chromium.org>

Acked-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: Oleg Nesterov <oleg at redhat.com>
> Cc: Andrew Morton <akpm at linux-foundation.org>
> Cc: Paul Menage <paul at paulmenage.org>
> ---
>  kernel/cgroup.c |   10 +++++++---
>  1 files changed, 7 insertions(+), 3 deletions(-)