Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751088AbXADEab (ORCPT ); Wed, 3 Jan 2007 23:30:31 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751074AbXADEab (ORCPT ); Wed, 3 Jan 2007 23:30:31 -0500 Received: from e2.ny.us.ibm.com ([32.97.182.142]:38360 "EHLO e2.ny.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750741AbXADEaa (ORCPT ); Wed, 3 Jan 2007 23:30:30 -0500 Date: Thu, 4 Jan 2007 10:00:46 +0530 From: Gautham R Shenoy To: Oleg Nesterov Cc: Gautham R Shenoy , Andrew Morton , Ingo Molnar , David Howells , Christoph Hellwig , linux-kernel@vger.kernel.org, dipankar@in.ibm.com, vatsa@in.ibm.com Subject: Re: [PATCH 3/2] fix flush_workqueue() vs CPU_DEAD race Message-ID: <20070104043046.GA15162@in.ibm.com> Reply-To: ego@in.ibm.com References: <20061230161031.GA101@tv-sign.ru> <20070102162727.9ce2ae2b.akpm@osdl.org> <20070103140459.GA12620@in.ibm.com> <20070103151704.GA28195@in.ibm.com> <20070103172657.GA1597@tv-sign.ru> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20070103172657.GA1597@tv-sign.ru> User-Agent: Mutt/1.5.11 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1199 Lines: 35 On Wed, Jan 03, 2007 at 08:26:57PM +0300, Oleg Nesterov wrote: > > I thought that these patches don't depend on each other, flush_work/workueue > don't care where cpu-hotplug takes workqueue_mutex, in CPU_LOCK_ACQUIRE or in > CPU_UP_PREPARE case (or CPU_DEAD/CPU_LOCK_RELEASE for unlock). > > Could you clarify? Just curious. You are right. They don't depend on each other. The intention behind introducing CPU_LOCK_ACQUIRE and CPU_LOCK_RELEASE was to have a standard place where the subsystems could acquire/release the "cpu hotplug protection" mutex in the cpu_hotplug callback function. The same can be acheived by acquiring these mutexes in CPU_UP_PREPARE/CPU_DOWN_PREPARE etc. This is true for every subsystem that is cpu-hotplug aware. > Oleg. > Thanks and Regards gautham. -- Gautham R Shenoy Linux Technology Center IBM India. "Freedom comes with a price tag of responsibility, which is still a bargain, because Freedom is priceless!" - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/