From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tejun Heo Subject: Re: [PATCH block/for-linus] writeback: fix syncing of I_DIRTY_TIME inodes Date: Mon, 24 Aug 2015 10:51:50 -0400 Message-ID: <20150824145150.GA10029@mtj.duckdns.org> References: <20150818174718.GA15739@mtj.duckdns.org> <20150818195439.GB15739@mtj.duckdns.org> <20150818215611.GD3902@dastard> <20150821102053.GL17933@dhcp-13-216.nay.redhat.com> <20150822003025.GS3902@dastard> <20150822044609.GM17933@dhcp-13-216.nay.redhat.com> <20150824011123.GA714@dastard> <20150824031816.GO17933@dhcp-13-216.nay.redhat.com> <20150824062425.GU3902@dastard> <20150824091959.GA2936@quack.suse.cz> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: Jens Axboe , Eryu Guan , linux-kernel@vger.kernel.org, xfs@oss.sgi.com, axboe@fb.com, Jan Kara , linux-fsdevel@vger.kernel.org, kernel-team@fb.com To: Jan Kara Return-path: Content-Disposition: inline In-Reply-To: <20150824091959.GA2936@quack.suse.cz> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: xfs-bounces@oss.sgi.com Sender: xfs-bounces@oss.sgi.com List-Id: linux-fsdevel.vger.kernel.org Hello, Jan. On Mon, Aug 24, 2015 at 11:19:59AM +0200, Jan Kara wrote: > > which shows unmount being the next writeback event queued and > > executed after the IO completions have come in (that missed the > > log). What is missing is the specific queue/exec events for > > sync_sb_inodes() from the sync code for each filesystem. > > Bah, I see the problem and indeed it was introduced by commit e79729123f639 > "writeback: don't issue wb_writeback_work if clean". The problem is that > we bail out of sync_inodes_sb() if there is no dirty IO. Which is wrong > because we have to wait for any outstanding IO (i.e. call wait_sb_inodes()) > regardless of dirty state! And that also explains why Tejun's patch fixes > the problem because it backs out the change to the exit condition in > sync_inodes_sb(). Dang, I'm an idiot sandwich. > So Tejun's patch from this thread is indeed fixing the real problem but the > comment in sync_inodes_sb() should be fixed to mention wait_sb_inodes() > must be called in all cases... Tejun, will you fixup the comment please? Will post an updated patch. Kudos to Eryu and Dave for chasing it down. Thanks a lot. -- tejun _______________________________________________ xfs mailing list xfs@oss.sgi.com http://oss.sgi.com/mailman/listinfo/xfs