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 C2C3A7FC3 for ; Wed, 14 Aug 2013 08:26:24 -0500 (CDT) Message-ID: <520B857C.9050607@sgi.com> Date: Wed, 14 Aug 2013 08:26:20 -0500 From: Mark Tinguely MIME-Version: 1.0 Subject: Re: [PATCH 50/50] xfs: use reference counts to free clean buffer items References: <1376304611-22994-1-git-send-email-david@fromorbit.com> <1376304611-22994-51-git-send-email-david@fromorbit.com> <520A4AB7.1080207@sgi.com> <20130813214648.GC6023@dastard> <520AAC79.1030608@sgi.com> <20130814035738.GD6023@dastard> In-Reply-To: <20130814035738.GD6023@dastard> List-Id: XFS Filesystem from SGI List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Errors-To: xfs-bounces@oss.sgi.com Sender: xfs-bounces@oss.sgi.com To: Dave Chinner Cc: xfs@oss.sgi.com On 08/13/13 22:57, Dave Chinner wrote: > On Tue, Aug 13, 2013 at 05:00:25PM -0500, Mark Tinguely wrote: >> On 08/13/13 16:46, Dave Chinner wrote: >>> On Tue, Aug 13, 2013 at 10:03:19AM -0500, Mark Tinguely wrote: >>>> On 08/12/13 05:50, Dave Chinner wrote: >>>>> From: Dave Chinner >>>>> >>>>> When a transaction is cancelled and the buffer log item is clean in >> >> ... >> >>>> >>>> why is a clean buffer on the AIL? Racing with a completion handler? >>> >>> "clean" means that it wasn't dirtied in the transaction - it can be >>> in the AIL and holding a reference count that way. >> >> I am wondering because it should not have made it into the CIL if it >> was not dirtied in a transaction - at least according to the the log >> item descriptor flag at least. > > CIL != AIL. IOWs, the bli_refcount going to zero doesn't always > mean the bli should be freed. All a zero value means is that it is > not tracked by any transaction. If the item is not going to be > placed in the AIL (or not already in the AIL) then it can be > released (freed). Clean or aborted items are not going into the AIL, > so they can be freed immeidately. Everything else needs to avoid > freeing the item until the correct state is reached, even if the ref > count goes to zero. > yep. You are saying that the problem is releasing a buffer that is clean and also in the AIL, I am just trying to figure out if you are fixing a symptom or the problem. --Mark. _______________________________________________ xfs mailing list xfs@oss.sgi.com http://oss.sgi.com/mailman/listinfo/xfs