Subject: Re: [PATCH v2 3/5] change number_of_cpusets to an atomic

From: KAMEZAWA Hiroyuki <[email-masked]>
Date: Tue, 24 Apr 2012 11:25:46 +0900

(2012/04/24 4:37), Glauber Costa wrote:

> This will allow us to call destroy() without holding the
> cgroup_mutex(). Other important updates inside update_flags()
> are protected by the callback_mutex.
> 
> We could protect this variable with the callback_mutex as well,
> as suggested by Li Zefan, but we need to make sure we are protected
> by that mutex at all times, and some of its updates happen inside the
> cgroup_mutex - which means we would deadlock.
> 
> An atomic variable is not expensive, since it is seldom updated,
> and protect us well.
> 
> Signed-off-by: Glauber Costa <[email-masked]>

Reviewed-by: KAMEZAWA Hiroyuki <[email-masked]>