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 p057YLUb123401 for ; Wed, 5 Jan 2011 01:34:22 -0600 Received: from mail.internode.on.net (localhost [127.0.0.1]) by cuda.sgi.com (Spam Firewall) with ESMTP id 8BC541D0E628 for ; Tue, 4 Jan 2011 23:36:28 -0800 (PST) Received: from mail.internode.on.net (bld-mail12.adl6.internode.on.net [150.101.137.97]) by cuda.sgi.com with ESMTP id aCRkiiyMzyFn4bRV for ; Tue, 04 Jan 2011 23:36:28 -0800 (PST) Date: Wed, 5 Jan 2011 18:36:25 +1100 From: Dave Chinner Subject: Re: [PATCH 5/8] xfs: split direct IO write path from xfs_file_aio_write Message-ID: <20110105073625.GA8322@dastard> References: <1294116518-14908-1-git-send-email-david@fromorbit.com> <1294116518-14908-6-git-send-email-david@fromorbit.com> <1294192495.2485.726.camel@doink> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <1294192495.2485.726.camel@doink> 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: Alex Elder Cc: xfs@oss.sgi.com On Tue, Jan 04, 2011 at 07:54:55PM -0600, Alex Elder wrote: > On Tue, 2011-01-04 at 15:48 +1100, Dave Chinner wrote: > > From: Dave Chinner > > > > The current xfs_file_aio_write code is a mess of locking shenanigans > > to handle the different locking requirements of buffered and direct > > IO. Start to clean this up by disentangling the direct IO path from > > the mess. > > All good, very good. But I'm not sure why you cut > out the code that backed off to buffered I/O if > generic_file_direct_write() returns an error. > (You gave no explanation.) Oh, I thought I put one in there. It's simple, though - XFS handles all allocation cases in the direct IO code and never returns a result that will require falling back to the buffered IO path. It is basically a code path that has been unused for years and all it does is make the logic much more complex to understand. I'll add that to the commit message.... Cheers, Dave. -- Dave Chinner david@fromorbit.com _______________________________________________ xfs mailing list xfs@oss.sgi.com http://oss.sgi.com/mailman/listinfo/xfs