From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tejun Heo Subject: Re: linux-next: workqueues tree build failure Date: Fri, 27 Nov 2009 17:42:27 +0900 Message-ID: <4B0F90F3.2010204@kernel.org> References: <20091126190050.3f9d7fef.sfr@canb.auug.org.au> <4B0E3677.6000603@kernel.org> <200911261016.58810.peter.ujfalusi@nokia.com> <4B0E467A.8080201@kernel.org> <1259239225.3062.16.camel@palomino.walls.org> <4B0F3331.3070107@kernel.org> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: Received: from hera.kernel.org ([140.211.167.34]:38087 "EHLO hera.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752393AbZK0Imm (ORCPT ); Fri, 27 Nov 2009 03:42:42 -0500 In-Reply-To: Sender: linux-next-owner@vger.kernel.org List-ID: To: Takashi Iwai Cc: Andy Walls , Peter Ujfalusi , Stephen Rothwell , "linux-next@vger.kernel.org" , "linux-kernel@vger.kernel.org" , Mark Brown Hello, 11/27/2009 05:37 PM, Takashi Iwai wrote: >> Sounds like it should be using bottom half tasklet not workqueue. >> Tasklet is exactly designed to handle situations like this. Is there >> any reason tasklet can't be used? > > Right now the h/w accessing code is using mutex. I'm not sure whether > the deeper part might sleep, though... Ah... I see. Using mutex from a handler where response time is critical is strange tho. Anyways, I don't really think singlethread will satisfy the timing requirement under loaded conditions. IMHO, update locking and using tasklets would be the best. Thanks. -- tejun