From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1761978AbYA1QrU (ORCPT ); Mon, 28 Jan 2008 11:47:20 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753496AbYA1QrI (ORCPT ); Mon, 28 Jan 2008 11:47:08 -0500 Received: from mx1.redhat.com ([66.187.233.31]:57808 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753348AbYA1QrG (ORCPT ); Mon, 28 Jan 2008 11:47:06 -0500 Message-ID: <479E06DE.5050608@redhat.com> Date: Mon, 28 Jan 2008 11:46:22 -0500 From: Steven Rostedt User-Agent: Thunderbird 1.5.0.12 (X11/20071019) MIME-Version: 1.0 To: "Rafael J. Wysocki" CC: Ingo Molnar , Andrew Morton , Linus Torvalds , LKML , Dmitry Adamushko , Peter Zijlstra Subject: Re: [Regression] 2.6.24-git3: Major annoyance during suspend/hibernation on x86-64 (bisected) References: <200801272229.48955.rjw@sisk.pl> <479D3287.1050604@redhat.com> <200801281231.51545.rjw@sisk.pl> <200801281731.37636.rjw@sisk.pl> In-Reply-To: <200801281731.37636.rjw@sisk.pl> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Rafael J. Wysocki wrote: > On Monday, 28 of January 2008, Rafael J. Wysocki wrote: >> On Monday, 28 of January 2008, Steven Rostedt wrote: >>> Rafael J. Wysocki wrote: >>> >>>> No, this isn't the WARN_ON(). >>>> >>>>> this does have the feel of being scheduling related, but are you >>>>> absolutely sure about the precise identity of the patch? >>>> Actually, not quite. That's why I have verified it and found that another >>>> patch is really responsible for the issue, namely: >>>> >>>> commit 82a1fcb90287052aabfa235e7ffc693ea003fe69 >>>> Author: Ingo Molnar >>>> Date: Fri Jan 25 21:08:02 2008 +0100 >>>> >>>> softlockup: automatically detect hung TASK_UNINTERRUPTIBLE tasks >>> Are you getting a bunch of prints from the softlockup detector in dmesg? >> No, I don't. In fact, I don't get _any_ messages from it whatsoever. >> >>> I wonder if the detector can detect a long timeout caused by suspend and >>> resume and if not is triggering false positives? >> I'm not sure, but the code is supposed to be suspend-aware, IIRC. However, >> I'm seeing a similar symptom on poweroff on an SMP x86-64 box, so it may be >> more directly related to the CPU hotplug. I'll try to verify that. > > As I expected, the delay is also observable when I do: > > echo 0 > /sys/devices/system/cpu/cpu1/online > > (it's variable, between 3 and 30 seconds). Again, no messages appear in dmesg > when this happens. > > I suspect I'll be able to reproduce it on another x86-64 SMP machine (I'm going > to try that later today). Could you download my tracing patches from here: http://people.redhat.com/srostedt/tracing/mcount-tracing-patches-v6.tar.bz2 Apply the above patches and select all but the histogram tracers. Then run this program http://people.redhat.com/srostedt/tracing/trace-cmd.c ./trace-cmd -f echo 0 > /sys/devices/system/cpu/cpu1/online then do this (mount debugfs): bzip2 -c /debugfs/tracing/latency_trace > /tmp/trace.bz2 and send the result to myself and Ingo. Thanks, -- Steve > > Thanks, > Rafael