Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752656Ab3IJPMY (ORCPT ); Tue, 10 Sep 2013 11:12:24 -0400 Received: from moutng.kundenserver.de ([212.227.126.186]:64867 "EHLO moutng.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752331Ab3IJPMW (ORCPT ); Tue, 10 Sep 2013 11:12:22 -0400 Date: Tue, 10 Sep 2013 17:12:14 +0200 (CEST) From: Guennadi Liakhovetski X-X-Sender: lyakh@axis700.grange To: Viresh Kumar cc: Greg KH , "Rafael J. Wysocki" , Linux Kernel Mailing List , "linux-arm-kernel@lists.infradead.org" , "linux-pm@vger.kernel.org" , "cpufreq@vger.kernel.org" , SH-Linux , Magnus Damm Subject: Re: "cpufreq: fix serialization issues with freq change notifiers" breaks cpufreq too In-Reply-To: Message-ID: References: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII X-Provags-ID: V02:K0:I5q2h3pwboqeey/Pp/C+QSAWcg55/tDhpXZOeDekP1H /dYBcZzA6JVIvFJFmwbE9qrXRtqoZ2lGPmX5/xQbGfvytqifdh jb8YfswR6jzDmpQ2Lc+JVu9wRTLeqJctuEGjnzycOElMY+53l8 1LPiPnBIqz2FMsdzNnNmgv8OqXswGNI3W29bP1UXOhrC2tXRBZ P4vcaRXht9vth3JME5f9sGYynCMyZeHDQbgQMNZJcKisCZ9O1s 2pxRkWN61lGsUpng+EcsQTX0c6cdaBj69BNh9gFuN4dYPRWuPg EcYZES/fP8tLPgRjyEAKl8RAoSNM2+N9q1oWtFx3BLiTu1PCQF /rLSJ/l0V4J3H0Ia3HOZZIYC/R83KQQa6DKx7v37dc1yu212nw /Na3PO1E3zZDw== Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2855 Lines: 93 On Tue, 10 Sep 2013, Viresh Kumar wrote: > On 9 September 2013 20:41, Guennadi Liakhovetski wrote: > > Sorry guys, I'm trying my best to stop this patch from propagating to > > stable and to get it fixed asap, so, the CC list might be a bit excessive. > > Also trying to fix the originally spare cc list, which makes it impossible > > for me to reply to the original thread, instead have to start a new one. > > > > Commit > > > > commit dceff5ce18801dddc220d6238628619c93bc3cb6 > > Author: Viresh Kumar > > Date: Sun Sep 1 22:19:37 2013 +0530 > > > > cpufreq: fix serialization issues with freq change notifiers > > > > breaks .transition_ongoing counting. This leads to cpufreq-cpu0 not > > working any more. In particular switching the governor from performance to > > powersave directly after boot doesn't result in a frequency switch any > > more. Reverting this patch fixes the problem again. Tested with today's > > -next. > > I have tested it again on my exynos and intel machines and couldn't see > a single problem with this patch.. Ok, here's what I've just done. 1. checkout -next tag next-20130909 commit 98926a8004b453089368fda456b8c869240e9953 Author: Stephen Rothwell Date: Mon Sep 9 16:05:53 2013 +1000 Add linux-next specific files for 20130909 2. built and booted a kernel for kzm9g (.config available on request) 3. cpufreq failed to initialise: cpufreq_cpu0: failed to find cpu0 node cpufreq-cpu0: probe of cpufreq-cpu0 failed with error -2 due to commit f837a9b5ab05c52a07108c6f09ca66f2e0aee757 - as reported in another thread. 4. reverted that commit, resolving a trivial conflict. Added a debug output in __cpufreq_driver_target() of if (cpufreq_disabled()) return -ENODEV; + pr_info("%s() %d\n", __func__, policy->transition_ongoing); if (policy->transition_ongoing) return -EBUSY; Built and booted, got cpufreq: __cpufreq_driver_target(): 1 printed out 4 times from the beginning. 5. tried echo powersave > /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor the above output appeared 2 more times - no frequency change resulted. 6. reverted commit dceff5ce18801dddc220d6238628619c93bc3cb6, built booted - cpufreq works again. > I am afraid you need to give us some more information on how it broke > your stuff.. :) Hope the above is enough. Thanks Guennadi > And I am also not sure cpufreq-cpu0 is different then any other driver.. > > -- > viresh --- Guennadi Liakhovetski, Ph.D. Freelance Open-Source Software Developer http://www.open-technology.de/ -- 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/