Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755005AbZDHM14 (ORCPT ); Wed, 8 Apr 2009 08:27:56 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755868AbZDHM1Y (ORCPT ); Wed, 8 Apr 2009 08:27:24 -0400 Received: from mx2.mail.elte.hu ([157.181.151.9]:43817 "EHLO mx2.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759367AbZDHM1X (ORCPT ); Wed, 8 Apr 2009 08:27:23 -0400 Date: Wed, 8 Apr 2009 14:26:13 +0200 From: Ingo Molnar To: Rusty Russell , =?iso-8859-1?Q?Fr=E9d=E9ric?= Weisbecker , Steven Rostedt Cc: Peter Zijlstra , "Rafael J. Wysocki" , Ming Lei , Andrew Morton , Linux-pm mailing list , Linux Kernel List , Gautham R Shenoy Subject: Re: pm-hibernate : possible circular locking dependency detected Message-ID: <20090408122613.GD18581@elte.hu> References: <200904071356.29914.rusty@rustcorp.com.au> <1239087953.798.5513.camel@twins> <200904081247.08712.rusty@rustcorp.com.au> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <200904081247.08712.rusty@rustcorp.com.au> User-Agent: Mutt/1.5.18 (2008-05-17) X-ELTE-VirusStatus: clean X-ELTE-SpamScore: -1.5 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-1.5 required=5.9 tests=BAYES_00 autolearn=no SpamAssassin version=3.2.3 -1.5 BAYES_00 BODY: Bayesian spam probability is 0 to 1% [score: 0.0000] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 995 Lines: 28 * Rusty Russell wrote: > On Tuesday 07 April 2009 16:35:53 Peter Zijlstra wrote: > > On Tue, 2009-04-07 at 13:56 +0930, Rusty Russell wrote: > > > Looks like this will be fixed by Andrew's work-on-cpu-in-own-thread > > > patch which I just put out the pull request for. > > > > Would it make sense to teach it about a short-circuit like: > > > > work_on_cpu() { > > > > if (cpumask_weight(current->cpus_allowed) == 1 && > > smp_processor_id() == cpu) > > return do_work_right_here(); > > Does that happen much? I guess put a counter in and see? a temporary tracepoint or trace_printk() for the workqueue tracer would also tell this, without any long-term overhead (it will be easy to remove it). Ingo -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/