From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757932Ab3HMRBv (ORCPT ); Tue, 13 Aug 2013 13:01:51 -0400 Received: from mail-gh0-f174.google.com ([209.85.160.174]:57746 "EHLO mail-gh0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756163Ab3HMRBu (ORCPT ); Tue, 13 Aug 2013 13:01:50 -0400 Date: Tue, 13 Aug 2013 13:01:46 -0400 From: Tejun Heo To: Stephen Boyd Cc: "Rafael J. Wysocki" , linux-kernel@vger.kernel.org Subject: Re: [PATCH] PM / QoS: Fix workqueue deadlock when using pm_qos_update_request_timeout() Message-ID: <20130813170146.GC32719@htj.dyndns.org> References: <1375992837-1673-1-git-send-email-sboyd@codeaurora.org> <20130813164315.GB32719@htj.dyndns.org> <520A62E2.6000309@codeaurora.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <520A62E2.6000309@codeaurora.org> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello, On Tue, Aug 13, 2013 at 09:46:26AM -0700, Stephen Boyd wrote: > >> + if (PM_QOS_DEFAULT_VALUE != req->node.prio) > >> + pm_qos_update_target( > >> + pm_qos_array[req->pm_qos_class]->constraints, > >> + &req->node, PM_QOS_UPDATE_REQ, > >> + PM_QOS_DEFAULT_VALUE); > > Maybe it'd be cleaner to add a param or internal variant of > > pm_qos_update_request()? > > Maybe, but I was trying to make a minimal fix here. Hmmm.... it just looks like things can easily get out of sync with the complex function call. I don't think it'll be too invasive if you introduce an internal variant which doesn't do the canceling. Rafael, what do you think? Thanks. -- tejun