From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail190.messagelabs.com (mail190.messagelabs.com [216.82.249.51]) by kanga.kvack.org (Postfix) with ESMTP id 536518D0001 for ; Fri, 5 Nov 2010 08:15:27 -0400 (EDT) Date: Fri, 5 Nov 2010 13:15:13 +0100 From: Johannes Weiner Subject: Re: [PATCH 2/2] writeback: stop background/kupdate works from livelocking other works Message-ID: <20101105121513.GC23393@cmpxchg.org> References: <20100913123110.372291929@intel.com> <20100913130149.994322762@intel.com> <20100914124033.GA4874@quack.suse.cz> <20101101121408.GB9006@localhost> <20101101122252.GA10637@localhost> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20101101122252.GA10637@localhost> Sender: owner-linux-mm@kvack.org To: Wu Fengguang Cc: Andrew Morton , Jan Kara , "linux-mm@kvack.org" , Mel Gorman , Rik van Riel , Minchan Kim , KAMEZAWA Hiroyuki , KOSAKI Motohiro , Dave Chinner , Christoph Hellwig , linux-fsdevel@vger.kernel.org List-ID: On Mon, Nov 01, 2010 at 08:22:52PM +0800, Wu Fengguang wrote: > From: Jan Kara > > Background writeback are easily livelockable (from a definition of their > target). This is inconvenient because it can make sync(1) stall forever waiting > on its queued work to be finished. Generally, when a flusher thread has > some work queued, someone submitted the work to achieve a goal more specific > than what background writeback does. So it makes sense to give it a priority > over a generic page cleaning. > > Thus we interrupt background writeback if there is some other work to do. We > return to the background writeback after completing all the queued work. > > Signed-off-by: Jan Kara > Signed-off-by: Wu Fengguang Reviewed-by: Johannes Weiner -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom policy in Canada: sign http://dissolvethecrtc.ca/ Don't email: email@kvack.org