Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754698AbXE3Ntl (ORCPT ); Wed, 30 May 2007 09:49:41 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753060AbXE3Nte (ORCPT ); Wed, 30 May 2007 09:49:34 -0400 Received: from mx3.mail.elte.hu ([157.181.1.138]:60236 "EHLO mx3.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752003AbXE3Ntd (ORCPT ); Wed, 30 May 2007 09:49:33 -0400 Date: Wed, 30 May 2007 15:49:07 +0200 From: Ingo Molnar To: Steven Rostedt Cc: Daniel Walker , Peter Zijlstra , linux-kernel@vger.kernel.org, Andrew Morton , Bill Huey , Jason Baron , Christoph Hellwig Subject: Re: [PATCH 3/5] lockstat: core infrastructure Message-ID: <20070530134907.GA27085@elte.hu> References: <20070529125248.877196281@chello.nl> <20070529130107.112347096@chello.nl> <1180470525.32594.71.camel@imap.mvista.com> <20070530132431.GA23947@elte.hu> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.4.2.2i X-ELTE-VirusStatus: clean X-ELTE-SpamScore: -2.0 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-2.0 required=5.9 tests=BAYES_00 autolearn=no SpamAssassin version=3.0.3 -2.0 BAYES_00 BODY: Bayesian spam probability is 0 to 1% [score: 0.0000] Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 777 Lines: 19 * Steven Rostedt wrote: > [...] We can argue that sched_clock is "good enough". If someone > wants better accounting of locks on some other arch, they can simply > change sched_clock to be more precise. exactly. Imprecise sched_clock() if there's a better fast clock source available is a bug in the architecture code. If the only available clocksource is 1 msec resolution then there's no solution and nothing to talk about - lock statistics will be 1msec granular just as much as scheduling. 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/