From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from cuda.sgi.com (cuda3.sgi.com [192.48.176.15]) by oss.sgi.com (8.14.3/8.14.3/SuSE Linux 0.8) with ESMTP id q2LNU0jX141789 for ; Wed, 21 Mar 2012 18:30:00 -0500 Received: from ipmail06.adl6.internode.on.net (ipmail06.adl6.internode.on.net [150.101.137.145]) by cuda.sgi.com with ESMTP id 3eF7S1hi15S4y7tH for ; Wed, 21 Mar 2012 16:29:58 -0700 (PDT) Date: Thu, 22 Mar 2012 10:29:56 +1100 From: Dave Chinner Subject: Re: [PATCH 3/4] xfs: allow assigning the tail lsn with the AIL lock held Message-ID: <20120321232956.GA5091@dastard> References: <20120316175541.258282540@bombadil.infradead.org> <20120316175636.373605151@bombadil.infradead.org> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20120316175636.373605151@bombadil.infradead.org> List-Id: XFS Filesystem from SGI List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: xfs-bounces@oss.sgi.com Errors-To: xfs-bounces@oss.sgi.com To: Christoph Hellwig Cc: xfs@oss.sgi.com On Fri, Mar 16, 2012 at 01:55:44PM -0400, Christoph Hellwig wrote: > Provide a variant of xlog_assign_tail_lsn that has the AIL lock already > held. By doing so we do an additional atomic_read + atomic_set under > the lock, which comes down to two instructions. > > Switch xfs_trans_ail_update_bulk and xfs_trans_ail_delete_bulk to the > new version to reduce the number of lock roundtrips, and prepare for > a new addition that would require a third lock roundtrip in > xfs_trans_ail_delete_bulk. What new addition is that? I don't see it in this patchset (maybe I'm just blind), so maybe this isn't necessary in the commit message? Cheers, Dave. -- Dave Chinner david@fromorbit.com _______________________________________________ xfs mailing list xfs@oss.sgi.com http://oss.sgi.com/mailman/listinfo/xfs