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 11:02:25 +0900 Message-ID: <4B0F3331.3070107@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> 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]:60323 "EHLO hera.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751491AbZK0CDG (ORCPT ); Thu, 26 Nov 2009 21:03:06 -0500 In-Reply-To: <1259239225.3062.16.camel@palomino.walls.org> Sender: linux-next-owner@vger.kernel.org List-ID: To: Andy Walls Cc: Peter Ujfalusi , Stephen Rothwell , "linux-next@vger.kernel.org" , "linux-kernel@vger.kernel.org" , Takashi Iwai , Mark Brown Hello, 11/26/2009 09:40 PM, Andy Walls wrote: >> * If you need to respond fast, wouldn't you be doing that from IRQ >> handler or softirq? Do you need task context? > > I'm not sure doing things like I2C transactions in the in the top half > of the IRQ handler is generally viable. On shared IRQ lines, wouldn't > this hold off the interrupt for another device for too long? > > For example, I already ran across the case of an error path in the ahci > disk controller driver interrupt handler holding off interrupts from the > cx18 driver longer than the CX23418 firmware would tolerate on a shared > interrupt line. 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? Thanks. -- tejun