Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755346Ab2BGHvf (ORCPT ); Tue, 7 Feb 2012 02:51:35 -0500 Received: from casper.infradead.org ([85.118.1.10]:33255 "EHLO casper.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751349Ab2BGHve (ORCPT ); Tue, 7 Feb 2012 02:51:34 -0500 Subject: Re: [BUG] perf: perf sched warning possibly due to clock granularity on AMD From: Peter Zijlstra To: Venki Pallipadi Cc: Borislav Petkov , Stephane Eranian , linux-kernel@vger.kernel.org, acme@redhat.com, mingo@elte.hu, robert.richter@amd.com, eric.dumazet@gmail.com, Andreas Herrmann In-Reply-To: References: <20120206132546.GA30854@quad> <1328538403.2482.4.camel@laptop> <20120206153408.GA31237@aftab> <1328546246.2482.10.camel@laptop> <20120206164626.GA31704@aftab> <1328547259.2482.11.camel@laptop> <20120206202722.GA556@aftab> <1328560293.2482.24.camel@laptop> <20120206203738.GB556@aftab> Content-Type: text/plain; charset="UTF-8" Date: Tue, 07 Feb 2012 08:51:08 +0100 Message-ID: <1328601068.2482.46.camel@laptop> Mime-Version: 1.0 X-Mailer: Evolution 2.32.2 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 630 Lines: 14 On Mon, 2012-02-06 at 13:19 -0800, Venki Pallipadi wrote: > > Yes. If these two flags are set, TSC should be consistent and sched_clock_stable > could be set and it will be reset if there is a call to mark_tsc_unstable(). Only trouble is that sched_clock_cpu() et al. will jump when you flip sched_clock_stable to 0 after you started using it.. its something we might want to fix. -- 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/