Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755619Ab3HaTCj (ORCPT ); Sat, 31 Aug 2013 15:02:39 -0400 Received: from mail-la0-f51.google.com ([209.85.215.51]:33710 "EHLO mail-la0-f51.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753796Ab3HaTCh (ORCPT ); Sat, 31 Aug 2013 15:02:37 -0400 Date: Sat, 31 Aug 2013 22:01:17 +0300 From: Sergey Senozhatsky To: Frederic Weisbecker Cc: Stanislaw Gruszka , 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: <20130831190117.GA2213@swordfish> References: <20130820111426.GA27828@swordfish.datadirectnet.com> <20130820151509.GA17441@somewhere> <20130820153549.GB2315@swordfish.minsk.epam.com> <20130820154257.GD17441@somewhere> <20130821153957.GA2969@swordfish.minsk.epam.com> <20130830230402.GA14760@somewhere> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20130830230402.GA14760@somewhere> 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: 1351 Lines: 32 On (08/31/13 01:04), Frederic Weisbecker wrote: > But stime should always be below rtime due to the calculation done by scale_stime() > which roughly sums up to: > > stime = (stime / stime + utime) * rtime > > So this shouldn't happen. > > I couldn't manage to reproduce it though. Can you still trigger it with latest -next? > > Thanks. Hello, I can't pull current -next (away from good network connection for a couple of days). What I have is 3.11.0-rc7-next-20130829: ps aux | grep rcu root 8 0.0 0.0 0 0 ? S Aug30 0:00 [rcuc/0] root 9 0.0 0.0 0 0 ? S Aug30 0:00 [rcub/0] root 10 21376376 0.0 0 0 ? S Aug30 21114581:36 [rcu_preempt] root 11 21376376 0.0 0 0 ? S Aug30 21114581:35 [rcuop/0] root 12 21376376 0.0 0 0 ? S Aug30 21114581:35 [rcuop/1] cat /proc/10/stat 10 (rcu_preempt) S 2 0 0 0 -1 2129984 0 0 0 0 1844674407370 715 0 0 20 0 1 0 10 0 0 18446744073709551615 0 0 0 0 0 0 0 2147483647 0 18446744073709551615 0 0 17 0 0 0 0 0 0 0 0 0 0 0 0 0 0 -ss -- 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/