From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755645Ab2BFRRo (ORCPT ); Mon, 6 Feb 2012 12:17:44 -0500 Received: from mx1.redhat.com ([209.132.183.28]:61042 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754464Ab2BFRRn (ORCPT ); Mon, 6 Feb 2012 12:17:43 -0500 Date: Mon, 6 Feb 2012 15:17:21 -0200 From: Arnaldo Carvalho de Melo To: Stephane Eranian Cc: Peter Zijlstra , linux-kernel@vger.kernel.org, mingo@elte.hu, robert.richter@amd.com, eric.dumazet@gmail.com, Borislav Petkov , Frederic Weisbecker , Thomas Gleixner Subject: Re: [BUG] perf: perf sched warning possibly due to clock granularity on AMD Message-ID: <20120206171721.GB6367@infradead.org> References: <20120206132546.GA30854@quad> <1328538403.2482.4.camel@laptop> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: X-Url: http://acmel.wordpress.com User-Agent: Mutt/1.5.19 (2009-01-05) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Em Mon, Feb 06, 2012 at 03:31:00PM +0100, Stephane Eranian escreveu: > On Mon, Feb 6, 2012 at 3:26 PM, Peter Zijlstra wrote: > > On Mon, 2012-02-06 at 14:25 +0100, Stephane Eranian wrote: > >> In summary, two issues: > >>   - Why is sched_clock_stable not set or even tested on recent AMD systems? > > > > I'll leave that for Robert to answer, also added Boris to the CC, him > > know AMD bits too. > > > Ok, good. > > >>   - perf should not rely on fine granularity timestamps in the re-ordering code > > > > Uhm, what else is there? > I understand your point. I don't quite understand what the code is > supposed to do for odered > samples. I'd like Arnaldo to explain this warning first. That code was written by Frédéric and IIRC also Thomas, its something I plan to rework somehow in the future, but for now I'll let them chime in... Frédéric? - Arnaldo