Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757696AbXKBPyx (ORCPT ); Fri, 2 Nov 2007 11:54:53 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755277AbXKBPyq (ORCPT ); Fri, 2 Nov 2007 11:54:46 -0400 Received: from mx2.mail.elte.hu ([157.181.151.9]:50978 "EHLO mx2.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754157AbXKBPyp (ORCPT ); Fri, 2 Nov 2007 11:54:45 -0400 Date: Fri, 2 Nov 2007 16:53:58 +0100 From: Ingo Molnar To: Balbir Singh Cc: Peter Zijlstra , Andrew Morton , Linux Kernel Mailing List Subject: Re: [PATCH] Fix delay accounting regression Message-ID: <20071102155358.GA32116@elte.hu> References: <20071102142220.24166.49046.sendpatchset@balbir-laptop> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20071102142220.24166.49046.sendpatchset@balbir-laptop> User-Agent: Mutt/1.5.16 (2007-06-09) 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 autolearn=no SpamAssassin version=3.1.7-deb -1.5 BAYES_00 BODY: Bayesian spam probability is 0 to 1% [score: 0.0051] Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 908 Lines: 20 * Balbir Singh wrote: > Fix the delay accounting regression introduced by commit > 75d4ef16a6aa84f708188bada182315f80aab6fa. rq no longer has sched_info > data associated with it. task_struct sched_info structure is used by > delay accounting to provide back statistics to user space. no, this really is broken code. sched_clock() is not a generally reliable time source so at a minimum the rq->clock fix i mentioned is needed. What user-space tools are utilizing delay-accounting by the way? We have most of this data available under SCHEDSTATS - how about consolidating CONFIG_TASK_DELAY_ACCT into CONFIG_SCHEDSTATS? 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/