From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760158Ab2JaTdf (ORCPT ); Wed, 31 Oct 2012 15:33:35 -0400 Received: from mail-da0-f46.google.com ([209.85.210.46]:39035 "EHLO mail-da0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755880Ab2JaTdd (ORCPT ); Wed, 31 Oct 2012 15:33:33 -0400 Date: Wed, 31 Oct 2012 12:33:29 -0700 From: Tejun Heo To: Michal Hocko Cc: lizefan@huawei.com, hannes@cmpxchg.org, bsingharora@gmail.com, kamezawa.hiroyu@jp.fujitsu.com, containers@lists.linux-foundation.org, cgroups@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 2/8] cgroup: kill CSS_REMOVED Message-ID: <20121031193329.GQ2945@htj.dyndns.org> References: <1351657365-25055-1-git-send-email-tj@kernel.org> <1351657365-25055-3-git-send-email-tj@kernel.org> <20121031153926.GC22809@dhcp22.suse.cz> <20121031165739.GE2945@htj.dyndns.org> <20121031191602.GB1271@dhcp22.suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20121031191602.GB1271@dhcp22.suse.cz> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hey, Michal. On Wed, Oct 31, 2012 at 08:16:02PM +0100, Michal Hocko wrote: > Sure, it cannot detect races but this wasn't the intention of the check. > The more important part is that memcg can outlive css and we want to > catch bugs when we try to charge to an already dead memcg. cgroup will provide mechanisms to perform such checks properly synchronized, so let's not leak internals like CSS rercnt going negative outside cgroup.c. Thanks. -- tejun