Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1761995AbXEKXh0 (ORCPT ); Fri, 11 May 2007 19:37:26 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754345AbXEKXhS (ORCPT ); Fri, 11 May 2007 19:37:18 -0400 Received: from mx1.redhat.com ([66.187.233.31]:48837 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754072AbXEKXhR (ORCPT ); Fri, 11 May 2007 19:37:17 -0400 Date: Sat, 12 May 2007 01:37:01 +0200 From: Tomas Janousek To: Andrew Morton Cc: john stultz , linux-kernel@vger.kernel.org, tsmetana@redhat.com, riel@redhat.com Subject: Re: [PATCH] Use boot based time for process start time and boot time in /proc Message-ID: <20070511233701.GA13437@redhat.com> References: <3108b4e2c91097ec9469420b3f0836f0499068a6.1178816485.git.tomi@nomi.cz> <20070510164047.263a9524.akpm@linux-foundation.org> <20070511084531.GA31854@redhat.com> <20070511125132.93a4abdd.akpm@linux-foundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20070511125132.93a4abdd.akpm@linux-foundation.org> User-Agent: Mutt/1.5.14 (2007-02-12) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1689 Lines: 54 Hi, On Fri, May 11, 2007 at 12:51:32PM -0700, Andrew Morton wrote: > On Fri, 11 May 2007 10:45:31 +0200 > Tomas Janousek wrote: > > > Hello, > > > > On Thu, May 10, 2007 at 04:40:47PM -0700, Andrew Morton wrote: > > > Tomas Janousek wrote: > > > > @@ -445,12 +445,14 @@ static int show_stat(struct seq_file *p, void *v) > > > > unsigned long jif; > > > > cputime64_t user, nice, system, idle, iowait, irq, softirq, steal; > > > > u64 sum = 0; > > > > + struct timespec boottime; > > > > > > > > user = nice = system = idle = iowait = > > > > irq = softirq = steal = cputime64_zero; > > > > - jif = - wall_to_monotonic.tv_sec; > > > > - if (wall_to_monotonic.tv_nsec) > > > > - --jif; > > > > + getboottime(&boottime); > > > > + jif = boottime.tv_sec; > > > > + if (boottime.tv_nsec) > > > > + ++jif; > > > > > > > > > getboottime(&boottime); > > jif = boottime.tv_sec; > > - if (boottime.tv_nsec) > > - ++jif; > > > So we've gone from --jif to ++jif to no change at all. > > Are you sure that this net removal of --jif is correct? Yes. Let's say wall_to_monotonic = { -10, 500000 } (which is { -9, -500000 }, and the original code would result in - (- 10) - 1 == 9). The getboottime calls set_normalized_timespec on { - (-10), - (500000) } which results to { 10 - 1, - 500000 + 1000000 } = { 9, 500000 }. tv_sec == 9 => correct. -- TJ. (Brno, CZ), BaseOS, Red Hat - 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/