From: Jan Kara Subject: Re: [PATCH] ext3: wait on all pending commits in ext3_sync_fs Date: Mon, 12 Jan 2009 23:28:34 +0100 Message-ID: <20090112222834.GA25494@atrey.karlin.mff.cuni.cz> References: <4908C951.2000309@redhat.com> <20081103184426.GA31894@ajones-laptop.nbttech.com> <20081103113318.35b0c266.akpm@linux-foundation.org> <20081103201428.GB30565@ajones-laptop.nbttech.com> <20081218231707.GB20092@atrey.karlin.mff.cuni.cz> <494ADEB3.8010109@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Arthur Jones , Andrew Morton , "linux-ext4@vger.kernel.org" , "sct@redhat.com" , "linux-kernel@vger.kernel.org" To: Eric Sandeen Return-path: Received: from atrey.karlin.mff.cuni.cz ([195.113.26.193]:56307 "EHLO atrey.karlin.mff.cuni.cz" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758788AbZALW2f (ORCPT ); Mon, 12 Jan 2009 17:28:35 -0500 Content-Disposition: inline In-Reply-To: <494ADEB3.8010109@redhat.com> Sender: linux-ext4-owner@vger.kernel.org List-ID: Hi Eric, > Jan Kara wrote: > > Hello, > > > > I'm sorry I'm replying late but I got time to react to this only now... > > > > >> I tried this and it too fixes the problem. FWIW I agree it > >> looks better... > > Well, shouldn't we rather fix what journal_start_commit() returns? > > The interface which returns 1 when a transaction is already committing or > > a transaction commit has just been started but 0 when we race with > > somebody staring the commit is fairly unusable. Moreover > > ext3_force_commit() will unnecessarily create new sync transaction and > > commit it if there's no transaction running which is quite expensive > > (even merging empty sync handle is not for free because of sync > > transaction batching). But this is minor problem since we probably > > don't care too much about sync() performance - BTW this is probably a > > cause for bug 12224, isn't it? > > Yep, it is! :) > > > BTW: ocfs2 would need fixing as well if done your way since it's > > sync_fs function has been copied over from ext3. > > To summarized I'd rather see a patch like below (untested) going in > > and your patch reverted... Opinions? I can cookup a JBD2 version of > > the patch in case we agree to go this way. > > Thanks, I'll look that over. Any chance you've looked over that patch? Thanks. Honza -- Jan Kara SuSE CR Labs