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

(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 <redacted>

Reviewed-by: KAMEZAWA Hiroyuki <redacted>