From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758849AbXLSBAy (ORCPT ); Tue, 18 Dec 2007 20:00:54 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753914AbXLSBAo (ORCPT ); Tue, 18 Dec 2007 20:00:44 -0500 Received: from mfe1.polimi.it ([131.175.12.23]:39168 "EHLO polimi.it" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751807AbXLSBAn (ORCPT ); Tue, 18 Dec 2007 20:00:43 -0500 Date: Wed, 19 Dec 2007 01:58:22 +0100 From: Stefano Brivio To: Ingo Molnar Cc: Andrew Morton , rjw@sisk.pl, linux-kernel@vger.kernel.org, torvalds@linux-foundation.org, Guillaume Chazarain Subject: Re: 2.6.24-rc4-git5: Reported regressions from 2.6.23 Message-ID: <20071219015822.1c9126e2@morte> In-Reply-To: <20071211090120.GA27690@elte.hu> References: <200712080340.49546.rjw@sisk.pl> <20071210204212.GA5502@elte.hu> <20071210125923.37bd2f10.akpm@linux-foundation.org> <20071210224508.GB27178@elte.hu> <20071210230425.GA641@elte.hu> <20071211003433.5cf0230d@morte> <20071211090120.GA27690@elte.hu> X-Mailer: Claws Mail 3.0.2 (GTK+ 2.12.1; i686-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-PMX-Version: 5.3.3.310218, Antispam-Engine: 2.5.2.311128, Antispam-Data: 2007.11.22.60028 X-PerlMx-Spam: Gauge=II, Probability=22%, Report='RELAY_IN_PBL_11 2.5, RDNS_GENERIC_POOLED 0, RDNS_SUSP 0, RDNS_SUSP_GENERIC 0, RELAY_IN_PBL 0, __CP_URI_IN_BODY 0, __CT 0, __CTE 0, __CT_TEXT_PLAIN 0, __HAS_MSGID 0, __HAS_X_MAILER 0, __MIME_TEXT_ONLY 0, __MIME_VERSION 0, __SANE_MSGID 0' Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 11 Dec 2007 10:01:20 +0100 Ingo Molnar wrote: > ok, just to make sure we are all synced up. I made 8 patches related to > this problem category (and all the trickle effects). 3 are upstream > already, 5 are pending for v2.6.25. One out of those 5 is an immaterial > cleanup patch - which leaves us 4 patches to sort out. > > So i'd suggest for you to try latest -git - that will tell us whether > udelay() is acceptable on your box right now. > > i've attached those 4 patches: > > x86-sched_clock-re-scheduler-fix-x86-regression-in-native-sched-clock.patch > x86-cpu-clock-idle-event.patch > sched-printk-recursion-fix.patch > sched-printk-clock-fix.patch > > none of them is _supposed_ to have any effect on udelay(), but the > interactions in this area are weird. Exactly, none of them have any effect on udelay(). > [ note: CONFIG_PRINTK_TIME will be broken and only fixed in v2.6.25, so > use some other time metric for determining mdelay quality. ] > > plus then there's this patch: > > http://lkml.org/lkml/2007/12/7/100 > > is it perhaps this one that fixed udelay for you? [ which would be much > more expected, as this patch changes udelay ;-) ] Yes, this one did. mdelay(2000) still gives delays between 2 and 2.9s, which is acceptable. I have marked the regression as CODE_FIX. -- Ciao Stefano