From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752517AbYKLMOj (ORCPT ); Wed, 12 Nov 2008 07:14:39 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751792AbYKLMO3 (ORCPT ); Wed, 12 Nov 2008 07:14:29 -0500 Received: from mx2.mail.elte.hu ([157.181.151.9]:53110 "EHLO mx2.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751790AbYKLMO3 (ORCPT ); Wed, 12 Nov 2008 07:14:29 -0500 Date: Wed, 12 Nov 2008 13:13:46 +0100 From: Ingo Molnar To: Steven Rostedt Cc: linux-kernel@vger.kernel.org, Andrew Morton , Frederic Weisbecker , Theodore Tso , Arjan van de Ven , Steven Rostedt Subject: Re: [PATCH] tracing: branch tracer, tweak output Message-ID: <20081112121346.GA14739@elte.hu> References: <20081112051438.843792214@goodmis.org> <20081112051518.503323629@goodmis.org> <20081112112536.GC31958@elte.hu> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20081112112536.GC31958@elte.hu> User-Agent: Mutt/1.5.18 (2008-05-17) X-ELTE-VirusStatus: clean X-ELTE-SpamScore: -1.5 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-1.5 required=5.9 tests=BAYES_00,DNS_FROM_SECURITYSAGE autolearn=no SpamAssassin version=3.2.3 -1.5 BAYES_00 BODY: Bayesian spam probability is 0 to 1% [score: 0.0000] 0.0 DNS_FROM_SECURITYSAGE RBL: Envelope sender in blackholes.securitysage.com Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org * Ingo Molnar wrote: > a small detail: > > > For example: > > > > bash-3471 [003] 357.014755: [INCORRECT] sched_info_dequeued:sched_stats.h:177 > > bash-3471 [003] 357.014756: [correct] update_curr:sched_fair.c:489 > > bash-3471 [003] 357.014758: [correct] calc_delta_fair:sched_fair.c:411 > > bash-3471 [003] 357.014759: [correct] account_group_exec_runtime:sched_stats.h:356 > > bash-3471 [003] 357.014761: [correct] update_curr:sched_fair.c:489 > > bash-3471 [003] 357.014763: [INCORRECT] calc_delta_fair:sched_fair.c:411 > > bash-3471 [003] 357.014765: [correct] calc_delta_mine:sched.c:1279 > > it's always good to have such fields aligned vertically. Something > like this would be shorter and visually much easier to parse: > > bash-3471 [003] 357.014755: [ MISS ] sched_info_dequeued:sched_stats.h:177 > bash-3471 [003] 357.014756: [ .... ] update_curr:sched_fair.c:489 > bash-3471 [003] 357.014758: [ .... ] calc_delta_fair:sched_fair.c:411 > > any objections against the patch below which implements this? and note that this is really a "branch tracer/profiler", with branch taken/untaken prediction hits/misses. The likely()/unlikely() is an in-kernel tool to manually predict branch likelyhood - and for now we trace and profile those points that we tweaked manually - but there's no reason why that should be true for future versions too. So i think it's generally better to think of these events as hit/miss events. Ingo