From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261234AbVFBISb (ORCPT ); Thu, 2 Jun 2005 04:18:31 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261248AbVFBISa (ORCPT ); Thu, 2 Jun 2005 04:18:30 -0400 Received: from [203.171.93.254] ([203.171.93.254]:21733 "EHLO cunningham.myip.net.au") by vger.kernel.org with ESMTP id S261234AbVFBIRo (ORCPT ); Thu, 2 Jun 2005 04:17:44 -0400 Subject: Re: Freezer Patches. From: Nigel Cunningham Reply-To: ncunningham@cyclades.com To: Benjamin Herrenschmidt Cc: Pavel Machek , Linux Kernel Mailing List In-Reply-To: <1117697772.31082.54.camel@gaston> References: <1117629212.10328.26.camel@localhost> <20050601130205.GA1940@openzaurus.ucw.cz> <1117663709.13830.34.camel@localhost> <20050601223101.GD11163@elf.ucw.cz> <1117665934.19020.94.camel@gaston> <20050601230235.GF11163@elf.ucw.cz> <1117676753.10888.105.camel@localhost> <20050602071431.GA1841@elf.ucw.cz> <1117697187.10888.138.camel@localhost> <20050602073119.GC1841@elf.ucw.cz> <1117697772.31082.54.camel@gaston> Content-Type: text/plain Organization: Cycades Message-Id: <1117700339.10888.141.camel@localhost> Mime-Version: 1.0 X-Mailer: Ximian Evolution 1.4.6-1mdk Date: Thu, 02 Jun 2005 18:18:59 +1000 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Hi Ben. On Thu, 2005-06-02 at 17:36, Benjamin Herrenschmidt wrote: > Whatever you guys decide to do (I actually do sys_sync() before freezing > on pmac and yes, it takes sometimes way too long), to be uber-safe, we > could/should _also_ do sync after freezing userland processes and before > freezing kernel threads (that is, splitting here). In fact, that would > help also avoid deadlocks where a frozen kernel thread is holding a > semaphore preventing a process from freezing. > > That way, if we sys_sync() once processes are sleeping and before kernel > threads are, we pretty-much make sure no new dirty buffer will appear. > > Anyway, that's mostly food for thoughts at this point I fully agree, and that's what I'm already doing. Nothing I can do about Pavel not seeing logic, so guess I just have to hope everyone else does :) Regards, Nigel