Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932837AbWKJKjG (ORCPT ); Fri, 10 Nov 2006 05:39:06 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932842AbWKJKjG (ORCPT ); Fri, 10 Nov 2006 05:39:06 -0500 Received: from gprs189-60.eurotel.cz ([160.218.189.60]:20448 "EHLO amd.ucw.cz") by vger.kernel.org with ESMTP id S932837AbWKJKjD (ORCPT ); Fri, 10 Nov 2006 05:39:03 -0500 Date: Fri, 10 Nov 2006 11:38:35 +0100 From: Pavel Machek To: David Chinner Cc: "Rafael J. Wysocki" , Alasdair G Kergon , Eric Sandeen , Andrew Morton , linux-kernel@vger.kernel.org, dm-devel@redhat.com, Srinivasa DS , Nigel Cunningham Subject: Re: [PATCH 2.6.19 5/5] fs: freeze_bdev with semaphore not mutex Message-ID: <20061110103835.GF3196@elf.ucw.cz> References: <20061107183459.GG6993@agk.surrey.redhat.com> <200611081310.19100.rjw@sisk.pl> <20061108180921.GA7708@ucw.cz> <200611091652.34649.rjw@sisk.pl> <20061109160003.GA24156@elf.ucw.cz> <20061110003332.GM8394166@melbourne.sgi.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20061110003332.GM8394166@melbourne.sgi.com> X-Warning: Reading this can be dangerous to your mental health. User-Agent: Mutt/1.5.11+cvs20060126 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1142 Lines: 28 Hi! > > > OTOH I have no idea _how_ we can tell xfs that the processes have been > > > frozen. Should we introduce a global flag for that or something? > > > > I guess XFS should just do all the writes from process context, and > > refuse any writing when its threads are frozen... I actually still > > believe it is doing the right thing, because you can't really write to > > disk from timer. > > As per the recent thread about this, XFS threads suspend correctly > and XFS doesn't issue I/O from timers. > > The problem appears to be per-cpu workqueues that don't get > suspended because suspend does not shut down workqueue threads. You Workqueues should be easy to handle. current->flags &= ~PF_NONFREEZE, and problem should be solved. Pavel -- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html - 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/