Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932960AbXF2E4o (ORCPT ); Fri, 29 Jun 2007 00:56:44 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751053AbXF2E4f (ORCPT ); Fri, 29 Jun 2007 00:56:35 -0400 Received: from netops-testserver-4-out.sgi.com ([192.48.171.29]:41757 "EHLO relay.sgi.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1750706AbXF2E4e (ORCPT ); Fri, 29 Jun 2007 00:56:34 -0400 Date: Fri, 29 Jun 2007 14:55:53 +1000 From: David Chinner To: Pavel Machek Cc: David Chinner , David Greaves , David Robinson , LVM general discussion and development , "'linux-kernel@vger.kernel.org'" , xfs@oss.sgi.com, linux-pm , LinuxRaid Subject: Re: [linux-lvm] 2.6.22-rc4 XFS fails after hibernate/resume Message-ID: <20070629045553.GN31489@sgi.com> References: <46744065.6060605@dgreaves.com> <4674645F.5000906@gmail.com> <46751D37.5020608@dgreaves.com> <4676390E.6010202@dgreaves.com> <20070618145007.GE85884050@sgi.com> <20070627204924.GA4777@ucw.cz> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20070627204924.GA4777@ucw.cz> User-Agent: Mutt/1.4.2.1i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1394 Lines: 36 On Wed, Jun 27, 2007 at 08:49:24PM +0000, Pavel Machek wrote: > Hi! > > > FWIW, I'm on record stating that "sync" is not sufficient to quiesce an XFS > > filesystem for a suspend/resume to work safely and have argued that the only > > Hmm, so XFS writes to disk even when its threads are frozen? They issue async I/O before they sleep and expects processing to be done on I/O completion via workqueues. > > safe thing to do is freeze the filesystem before suspend and thaw it after > > resume. This is why I originally asked you to test that with the other problem > > Could you add that to the XFS threads if it is really required? They > do know that they are being frozen for suspend. We don't suspend the threads on a filesystem freeze - they continue run. A filesystem freeze guarantees the filesystem clean and that the in memory state matches what is on disk. It is not possible for the filesytem to issue I/O or have outstanding I/O when it is in the frozen state, so the state of the threads and/or workqueues does not matter because they will be idle. Cheers, Dave. -- Dave Chinner Principal Engineer SGI Australian Software Group - 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/