[<prev] [next>] [<thread-prev] [day] [month] [year] [list]
Message-ID: <20110720070105.GC10857@tiehlicka.suse.cz>
Date: Wed, 20 Jul 2011 09:01:05 +0200
From: Michal Hocko <mhocko@...e.cz>
To: KAMEZAWA Hiroyuki <kamezawa.hiroyu@...fujitsu.com>
Cc: linux-mm@...ck.org, Balbir Singh <bsingharora@...il.com>,
Andrew Morton <akpm@...ux-foundation.org>,
linux-kernel@...r.kernel.org
Subject: Re: [PATCH 2/2] memcg: change memcg_oom_mutex to spinlock
On Wed 20-07-11 14:55:53, KAMEZAWA Hiroyuki wrote:
> On Thu, 14 Jul 2011 17:29:51 +0200
> Michal Hocko <mhocko@...e.cz> wrote:
>
> > memcg_oom_mutex is used to protect memcg OOM path and eventfd interface
> > for oom_control. None of the critical sections which it protects sleep
> > (eventfd_signal works from atomic context and the rest are simple linked
> > list resp. oom_lock atomic operations).
> > Mutex is also too heavy weight for those code paths because it triggers
> > a lot of scheduling. It also makes makes convoying effects more visible
> > when we have a big number of oom killing because we take the lock
> > mutliple times during mem_cgroup_handle_oom so we have multiple places
> > where many processes can sleep.
> >
> > Signed-off-by: Michal Hocko <mhocko@...e.cz>
>
> Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@...fujitsu.com>
Thanks!
--
Michal Hocko
SUSE Labs
SUSE LINUX s.r.o.
Lihovarska 1060/12
190 00 Praha 9
Czech Republic
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists