Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758147Ab3D2R3Z (ORCPT ); Mon, 29 Apr 2013 13:29:25 -0400 Received: from oproxy13-pub.unifiedlayer.com ([69.89.16.30]:60798 "HELO oproxy13-pub.unifiedlayer.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1757381Ab3D2R3Y (ORCPT ); Mon, 29 Apr 2013 13:29:24 -0400 Message-ID: <1367256561.8833.9.camel@Wailaba2> Subject: Re: [PATCH v2 1/3] process cputimer is moving faster than its corresponding clock From: Olivier Langlois To: Frederic Weisbecker Cc: Peter Zijlstra , Ingo Molnar , Thomas Gleixner , schwidefsky@de.ibm.com, Steven Rostedt , KOSAKI Motohiro , LKML Date: Mon, 29 Apr 2013 13:29:21 -0400 In-Reply-To: References: <1365184746.874.103.camel@Wailaba2> <1365593710.30071.52.camel@laptop> <1365608911.707.65.camel@Wailaba2> <1365763837.17140.52.camel@laptop> <1365782115.17140.68.camel@laptop> <1366951210.7911.28.camel@Wailaba2> <1366957639.7911.42.camel@Wailaba2> <517AD0AE.1030404@gmail.com> <1367037606.7911.66.camel@Wailaba2> Organization: Trillion01 Inc Content-Type: text/plain; charset="ISO-8859-1" X-Mailer: Evolution 3.8.1 Mime-Version: 1.0 Content-Transfer-Encoding: 7bit X-Identified-User: {5686:box610.bluehost.com:olivierl:trillion01.com} {sentby:smtp auth 173.178.230.31 authed with olivier@trillion01.com} Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1712 Lines: 46 On Mon, 2013-04-29 at 02:45 +0200, Frederic Weisbecker wrote: > 2013/4/27 Olivier Langlois : > > > > > > Forbids the cputimer to drift ahead of its process clock by > > blocking its update when a tick occurs while a autoreaping task > > is currently in do_exit() between the call to release_task() and > > its final call to schedule(). > > > > Any task stats update after having called release_task() will > > be lost because they are added to the global process stats located > > in the signal struct from release_task(). > > > > Ideally, you should postpone the release_task() call after the > > final context switch to get all the stats added but this is > > more complex to achieve. > > > > In other words, this is slowing down the cputimer so it keep the same > > pace than the process clock but in fact, what should be done is to > > speed up the process clock by adding the missing stats to it. > > > > Signed-off-by: Olivier Langlois > > Thanks. > > Could you please resend these three patches in a new mail thread to > make reviews easier? Also it would be nice to propose a different > subject for each individual patch. Each of which describing what the > patch does in a few words. > > Thanks. Frederic, Ok. I will do it and keep the description brief. If someone inquire more details, I will make them refer back to specific post inside this thread to avoid unnecessary repetition. Is this cool? -- 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/