From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756052AbbAZKX7 (ORCPT ); Mon, 26 Jan 2015 05:23:59 -0500 Received: from atrey.karlin.mff.cuni.cz ([195.113.26.193]:60168 "EHLO atrey.karlin.mff.cuni.cz" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752703AbbAZKXy (ORCPT ); Mon, 26 Jan 2015 05:23:54 -0500 Date: Mon, 26 Jan 2015 11:23:52 +0100 From: Pavel Machek To: "Fu, Zhonghui" Cc: "Rafael J. Wysocki" , len.brown@intel.com, Greg Kroah-Hartman , linux-pm@vger.kernel.org, "linux-kernel@vger.kernel.org" , chuansheng.liu@intel.com Subject: Change behaviour when tracing ... nasty trap (was Re: [PATCH] PM/Trace: get rid of synchronous resume limit during PM trace) Message-ID: <20150126102352.GA1758@amd> References: <54C5CB77.4000109@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <54C5CB77.4000109@linux.intel.com> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon 2015-01-26 13:07:03, Fu, Zhonghui wrote: > >From f9c841d1f943d81b5ab0aac7483e794a7f966296 Mon Sep 17 00:00:00 2001 > From: Zhonghui Fu > Date: Mon, 26 Jan 2015 11:27:08 +0800 > Subject: [PATCH] PM/Trace: get rid of synchronous resume limit during PM trace > > There are some kind of dependency between devices in some > hardware platforms. So, asynchronous resuming devices may > hang system due to wrong resume order. As a result, should > not fore synchronously resuming devices during tracing > PM events. > > Signed-off-by: Zhonghui Fu > --- > drivers/base/power/main.c | 3 +-- > include/linux/resume-trace.h | 7 ------- > 2 files changed, 1 insertions(+), 9 deletions(-) > > diff --git a/drivers/base/power/main.c b/drivers/base/power/main.c > index 9717d5f..5df148b 100644 > --- a/drivers/base/power/main.c > +++ b/drivers/base/power/main.c > @@ -517,8 +517,7 @@ static int device_resume_noirq(struct device *dev, pm_message_t state, bool asyn > > static bool is_async(struct device *dev) > { > - return dev->power.async_suspend && pm_async_enabled > - && !pm_trace_is_enabled(); > + return dev->power.async_suspend && pm_async_enabled; > } > Actually... whoever did the original patch was evil person. Changing behaviour when tracing is requested is evil, evil, evil. Git blame tells me Signed-off-by: Chuansheng Liu went to the dark side. Pavel -- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html