Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760482Ab3ICScf (ORCPT ); Tue, 3 Sep 2013 14:32:35 -0400 Received: from mail-ee0-f43.google.com ([74.125.83.43]:38214 "EHLO mail-ee0-f43.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1760215Ab3ICScd (ORCPT ); Tue, 3 Sep 2013 14:32:33 -0400 Date: Tue, 3 Sep 2013 20:32:29 +0200 From: Ingo Molnar To: Sergey Senozhatsky Cc: Stanislaw Gruszka , Frederic Weisbecker , Ingo Molnar , Peter Zijlstra , "Paul E. McKenney" , Borislav Petkov , linux-kernel@vger.kernel.org Subject: Re: [sched next] overflowed cpu time for kernel threads in /proc/PID/stat Message-ID: <20130903183229.GB30757@gmail.com> References: <20130820153549.GB2315@swordfish.minsk.epam.com> <20130820154257.GD17441@somewhere> <20130821153957.GA2969@swordfish.minsk.epam.com> <20130830230402.GA14760@somewhere> <20130902122845.GA2457@swordfish.minsk.epam.com> <20130902130744.GB2378@somewhere> <20130902135033.GA1686@redhat.com> <20130902140015.GB2368@swordfish.minsk.epam.com> <20130903084306.GA2694@redhat.com> <20130903180912.GA2340@swordfish> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20130903180912.GA2340@swordfish> 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 Content-Length: 1256 Lines: 32 * Sergey Senozhatsky wrote: > On (09/03/13 10:43), Stanislaw Gruszka wrote: > > Ok, I see now, utime is 0 . This seems to be problem with dynamic ticks > > as you told that your application is kernel compilation, so we utilize > > lot of cpu time in user-space. > > > > Anyway we should handle utime == 0 situation on scaling code. We work > > well when rtime & stime are not big (variables and results fit in > > 32 bit), otherwise we have that stime bigger than rtime problem. Let's > > try to handle the problem by below patch. Sergey, does it work for you ? > > checked on -current and -next -- works fine, good job. > > here are my: > Reported-by: Sergey Senozhatsky > Tested-by: Sergey Senozhatsky Cool and thanks for the patient reporting and testing! Stanislaw, mind sending a changelogged, signed off patch with Sergey's tags included? It also warrants a -stable backport tag I think. Thanks, 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/