From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from relay.sgi.com (relay2.corp.sgi.com [137.38.102.29]) by oss.sgi.com (Postfix) with ESMTP id C3B207CA3 for ; Thu, 2 Jun 2016 18:08:30 -0500 (CDT) Received: from cuda.sgi.com (cuda1.sgi.com [192.48.157.11]) by relay2.corp.sgi.com (Postfix) with ESMTP id 84279304032 for ; Thu, 2 Jun 2016 16:08:27 -0700 (PDT) Received: from ipmail04.adl6.internode.on.net (ipmail04.adl6.internode.on.net [150.101.137.141]) by cuda.sgi.com with ESMTP id uzex0dmIMRie33UA for ; Thu, 02 Jun 2016 16:08:25 -0700 (PDT) Date: Fri, 3 Jun 2016 09:08:13 +1000 From: Dave Chinner Subject: Re: shrink_active_list/try_to_release_page bug? (was Re: xfs trace in 4.4.2 / also in 4.3.3 WARNING fs/xfs/xfs_aops.c:1232 xfs_vm_releasepage) Message-ID: <20160602230813.GQ12670@dastard> References: <574BEA84.3010206@profihost.ag> <20160530223657.GP26977@dastard> <20160531010724.GA9616@bbox> <20160531025509.GA12670@dastard> <20160531035904.GA17371@bbox> <20160531060712.GC12670@dastard> <574D2B1E.2040002@profihost.ag> <20160531073119.GD12670@dastard> <575022D2.7030502@profihost.ag> <57502A2E.60702@applied-asynchrony.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <57502A2E.60702@applied-asynchrony.com> List-Id: XFS Filesystem from SGI List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Errors-To: xfs-bounces@oss.sgi.com Sender: xfs-bounces@oss.sgi.com To: Holger =?iso-8859-1?Q?Hoffst=E4tte?= Cc: Minchan Kim , Brian Foster , Stefan Priebe - Profihost AG , linux-kernel@vger.kernel.org, "xfs@oss.sgi.com" , linux-mm@kvack.org On Thu, Jun 02, 2016 at 02:44:30PM +0200, Holger Hoffst=E4tte wrote: > On 06/02/16 14:13, Stefan Priebe - Profihost AG wrote: > > = > > Am 31.05.2016 um 09:31 schrieb Dave Chinner: > >> On Tue, May 31, 2016 at 08:11:42AM +0200, Stefan Priebe - Profihost AG= wrote: > >>>> I'm half tempted at this point to mostly ignore this mm/ behavour > >>>> because we are moving down the path of removing buffer heads from > >>>> XFS. That will require us to do different things in ->releasepage > >>>> and so just skipping dirty pages in the XFS code is the best thing > >>>> to do.... > >>> > >>> does this change anything i should test? Or is 4.6 still the way to g= o? > >> > >> Doesn't matter now - the warning will still be there on 4.6. I think > >> you can simply ignore it as the XFS code appears to be handling the > >> dirty page that is being passed to it correctly. We'll work out what > >> needs to be done to get rid of the warning for this case, wether it > >> be a mm/ change or an XFS change. > > = > > Any idea what i could do with 4.4.X? Can i safely remove the WARN_ONCE > > statement? > = > By definition it won't break anything since it's just a heads-up message, > so yes, it should be "safe". However if my understanding of the situation > is correct, mainline commit f0281a00fe "mm: workingset: only do workingset > activations on reads" (+ friends) in 4.7 should effectively prevent this > from happenning. Can someone confirm or deny this? I don't think it will. The above commits will avoid putting /write-only/ dirty pages on the active list from the write() syscall vector, but it won't prevent pages that are read first then dirtied from ending up on the active list. e.g. a mmap write will first read the page from disk to populate the page (hence it ends up on the active list), then the page gets dirtied and ->page_mkwrite is called to tell the filesystem.... Cheers, Dave. -- = Dave Chinner david@fromorbit.com _______________________________________________ xfs mailing list xfs@oss.sgi.com http://oss.sgi.com/mailman/listinfo/xfs