From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753260Ab1GZULO (ORCPT ); Tue, 26 Jul 2011 16:11:14 -0400 Received: from cantor2.suse.de ([195.135.220.15]:58056 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751934Ab1GZULL (ORCPT ); Tue, 26 Jul 2011 16:11:11 -0400 Date: Tue, 26 Jul 2011 22:10:38 +0200 From: Jan Kara To: Linus Torvalds Cc: Jan Kara , Al Viro , Josef Bacik , LKML , linux-fsdevel@vger.kernel.org Subject: Re: [PULL REQUEST] ext3, jbd, ext2, and quota fixes for 3.1-rc1 Message-ID: <20110726201038.GE27993@quack.suse.cz> References: <20110726181418.GA27993@quack.suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: User-Agent: Mutt/1.5.20 (2009-06-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue 26-07-11 11:36:29, Linus Torvalds wrote: > On Tue, Jul 26, 2011 at 11:14 AM, Jan Kara wrote: > > > >  could you please pull from > > > > git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs-2.6.git for_linus > > Ok, this clashed with the fsync mutex pushdown, and the whole addition > of fixed tracepoints. > > Quite frankly, I think the fixed tracepoints are broken and make the > code unreadable (why have them?) but I fixed it up. > > Somebody should really double-check the resolve. That's especially > true since the whole i_mutex thing is *also* rather dubious. The > comment that moved that down says: > > + /* > + * Taking the mutex here just to keep consistent with how fsync was > + * called previously, however it looks like we don't need to take > + * i_mutex at all. > + */ > > but in fact it is *not* consistent with how fsync() used to be called, > since we then drop the mutex *before* doing > > return ext3_force_commit(inode->i_sb); > > for the should_journal_data case. > > See commit 02c24a82187 ("fs: push i_mutex and filemap_write_and_wait > down into ->fsync() handlers"). > > I resolved it with the mutex still dropped early (especially since the > comment implies it may not matter at all), but quite frankly, > everything I did around that resolve made me go "that code is just > WRONG". Both wrt the tracepoints and wrt the i_mutex. > > So I think my resolution is "correct" from a merge standpoint, but I > think the code is total crap. I also wonder whether you can really do > that > > J_ASSERT(ext3_journal_current_handle() == NULL); > > without holding the i_mutex, so I moved that back down again. > > So I *really* want people to take a look at that ext3_sync_file() > function. Please? ext3_sync_file() really does not need i_mutex for anything. I've just checked how you resolved the conflict and it looks nice. I'll queue a patch which just removes i_mutex from that function altogether. Thanks for the resolve. Honza -- Jan Kara SUSE Labs, CR