From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from cuda.sgi.com (cuda1.sgi.com [192.48.157.11]) by oss.sgi.com (8.14.3/8.14.3/SuSE Linux 0.8) with ESMTP id q7N55Eoq136125 for ; Thu, 23 Aug 2012 00:05:14 -0500 Received: from ipmail04.adl6.internode.on.net (ipmail04.adl6.internode.on.net [150.101.137.141]) by cuda.sgi.com with ESMTP id sQjn7dlAVbMDq8Cm for ; Wed, 22 Aug 2012 22:05:59 -0700 (PDT) Received: from disappointment ([192.168.1.1]) by dastard with esmtp (Exim 4.76) (envelope-from ) id 1T4Pbz-0003Kc-Ia for xfs@oss.sgi.com; Thu, 23 Aug 2012 15:05:43 +1000 Received: from dave by disappointment with local (Exim 4.80) (envelope-from ) id 1T4Pbz-0003jb-Fu for xfs@oss.sgi.com; Thu, 23 Aug 2012 15:05:43 +1000 From: Dave Chinner Subject: [PATCH 100/102] xfs: don't defer metadata allocation to the workqueue Date: Thu, 23 Aug 2012 15:02:58 +1000 Message-Id: <1345698180-13612-101-git-send-email-david@fromorbit.com> In-Reply-To: <1345698180-13612-1-git-send-email-david@fromorbit.com> References: <1345698180-13612-1-git-send-email-david@fromorbit.com> List-Id: XFS Filesystem from SGI List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 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: xfs@oss.sgi.com From: Dave Chinner Upstream commit: aa292847b9fc6e187547110de833a7d3131bbddf Almost all metadata allocations come from shallow stack usage situations. Avoid the overhead of switching the allocation to a workqueue as we are not in danger of running out of stack when making these allocations. Metadata allocations are already marked through the args that are passed down, so this is trivial to do. Signed-off-by: Dave Chinner Reported-by: Mel Gorman Tested-by: Mel Gorman Signed-off-by: Ben Myers --- fs/xfs/xfs_alloc.c | 15 ++++++++++++--- 1 file changed, 12 insertions(+), 3 deletions(-) diff --git a/fs/xfs/xfs_alloc.c b/fs/xfs/xfs_alloc.c index de5a353..5d830cf 100644 --- a/fs/xfs/xfs_alloc.c +++ b/fs/xfs/xfs_alloc.c @@ -2441,13 +2441,22 @@ xfs_alloc_vextent_worker( current_restore_flags_nested(&pflags, PF_FSTRANS); } - -int /* error */ +/* + * Data allocation requests often come in with little stack to work on. Push + * them off to a worker thread so there is lots of stack to use. Metadata + * requests, OTOH, are generally from low stack usage paths, so avoid the + * context switch overhead here. + */ +int xfs_alloc_vextent( - xfs_alloc_arg_t *args) /* allocation argument structure */ + struct xfs_alloc_arg *args) { DECLARE_COMPLETION_ONSTACK(done); + if (!args->userdata) + return __xfs_alloc_vextent(args); + + args->done = &done; INIT_WORK_ONSTACK(&args->work, xfs_alloc_vextent_worker); queue_work(xfs_alloc_wq, &args->work); -- 1.7.10 _______________________________________________ xfs mailing list xfs@oss.sgi.com http://oss.sgi.com/mailman/listinfo/xfs