From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932567AbXAQQZM (ORCPT ); Wed, 17 Jan 2007 11:25:12 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932572AbXAQQZM (ORCPT ); Wed, 17 Jan 2007 11:25:12 -0500 Received: from e35.co.us.ibm.com ([32.97.110.153]:41490 "EHLO e35.co.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932567AbXAQQZK (ORCPT ); Wed, 17 Jan 2007 11:25:10 -0500 Date: Wed, 17 Jan 2007 21:55:01 +0530 From: Srivatsa Vaddagiri To: Oleg Nesterov Cc: Andrew Morton , David Howells , Christoph Hellwig , Ingo Molnar , Linus Torvalds , linux-kernel@vger.kernel.org, Gautham shenoy , "Pallipadi, Venkatesh" Subject: Re: [PATCH] flush_cpu_workqueue: don't flush an empty ->worklist Message-ID: <20070117162501.GF26211@in.ibm.com> Reply-To: vatsa@in.ibm.com References: <20070109165655.GA215@tv-sign.ru> <20070114235410.GA6165@tv-sign.ru> <20070115043304.GA16435@in.ibm.com> <20070115125401.GA134@tv-sign.ru> <20070115161810.GB16435@in.ibm.com> <20070115165516.GA254@tv-sign.ru> <20070116052606.GA995@in.ibm.com> <20070116132725.GA81@tv-sign.ru> <20070117061705.GB2803@in.ibm.com> <20070117154716.GA104@tv-sign.ru> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20070117154716.GA104@tv-sign.ru> User-Agent: Mutt/1.5.11 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Jan 17, 2007 at 06:47:16PM +0300, Oleg Nesterov wrote: > Btw, I agree it is good to have a sleeping lock to protect cpu_online_map. > But it should be separate from workqueue_mutex, and it is not needed for > create/destroy/flush funcs. Which is what lock_cpu_hotplug() attempted to provide but which has recd lot of flak in recent days. I guess if someone implements process freezer based locking of cpu_online_map, we will know better how suited later is for cpu hotplug. -- Regards, vatsa