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 (8.14.3/8.14.3/SuSE Linux 0.8) with ESMTP id q54HPi80249563 for ; Mon, 4 Jun 2012 12:25:44 -0500 Message-ID: <4FCCEF94.7020501@sgi.com> Date: Mon, 04 Jun 2012 12:25:40 -0500 From: Mark Tinguely MIME-Version: 1.0 Subject: Re: [PATCH] xfs: re-enable xfsaild idle mode and fix associated races References: <1337875602-63025-1-git-send-email-bfoster@redhat.com> In-Reply-To: <1337875602-63025-1-git-send-email-bfoster@redhat.com> 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" Sender: xfs-bounces@oss.sgi.com Errors-To: xfs-bounces@oss.sgi.com To: Brian Foster Cc: xfs@oss.sgi.com On 05/24/12 11:06, Brian Foster wrote: > xfsaild idle mode logic currently leads to a couple hangs: > > 1.) If xfsaild is rescheduled in during an incremental scan > (i.e., tout != 0) and the target has been updated since > the previous run, we can hit the new target and go into > idle mode with a still populated ail. > 2.) A wake up is only issued when the target is pushed forward. > The wake up can race with xfsaild if it is currently in the > process of entering idle mode, causing future wake up > events to be lost. > > Both hangs are reproducible by running xfstests 273 in a loop. > Modify xfsaild to enter idle mode only when the ail is empty > and the push target has not been moved forward since the last > push. > > Signed-off-by: Brian Foster > --- I wouldn't mind keeping an large (a few minutes) wake up value for the empty AIL case to be paranoid. Reviewed-by: Mark Tinguely _______________________________________________ xfs mailing list xfs@oss.sgi.com http://oss.sgi.com/mailman/listinfo/xfs