From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1750872AbXCHKcU (ORCPT ); Thu, 8 Mar 2007 05:32:20 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1750891AbXCHKcT (ORCPT ); Thu, 8 Mar 2007 05:32:19 -0500 Received: from e1.ny.us.ibm.com ([32.97.182.141]:38095 "EHLO e1.ny.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750858AbXCHKcS (ORCPT ); Thu, 8 Mar 2007 05:32:18 -0500 Date: Thu, 8 Mar 2007 16:08:08 +0530 From: Srivatsa Vaddagiri To: "Paul Menage" Cc: sekharan@us.ibm.com, ckrm-tech@lists.sourceforge.net, linux-kernel@vger.kernel.org, xemul@sw.ru, dev@sw.ru, containers@lists.osdl.org, pj@sgi.com, ebiederm@xmission.com, mbligh@google.com, winget@google.com, rohitseth@google.com, serue@us.ibm.com, devel@openvz.org Subject: Re: [ckrm-tech] [PATCH 1/7] containers (V7): Generic container system abstracted from cpusets code Message-ID: <20070308103808.GH6504@in.ibm.com> Reply-To: vatsa@in.ibm.com References: <20070212081521.808338000@menage.corp.google.com> <20070212085104.130746000@menage.corp.google.com> <20070307122117.GB2336@in.ibm.com> <6599ad830703071250p6c92a357g51391a23ee3d78d8@mail.gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <6599ad830703071250p6c92a357g51391a23ee3d78d8@mail.gmail.com> User-Agent: Mutt/1.5.11 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Mar 07, 2007 at 12:50:03PM -0800, Paul Menage wrote: > The callback mutex (which is what container_lock() actually locks) is > also used to synchronize fork/exit against subsystem additions, in the > event that some subsystem has registered fork or exit callbacks. We > could probably have a separate subsystem_mutex for that instead. Why can't manage_mutex itself be used there (to serialize fork/exit callbacks against modification to hierarchy)? > Apart from that, yes, it may well be possible to move callback lock > entirely inside cpusets. Yes, that way only the hierarchy hosting cpusets takes the hit of double-locking. cpuset_subsys->create/destroy can take this additional lock inside cpuset.c. -- Regards, vatsa