From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754704AbcBBLYf (ORCPT ); Tue, 2 Feb 2016 06:24:35 -0500 Received: from foss.arm.com ([217.140.101.70]:54699 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754207AbcBBLYd (ORCPT ); Tue, 2 Feb 2016 06:24:33 -0500 Date: Tue, 2 Feb 2016 11:25:11 +0000 From: Juri Lelli To: Viresh Kumar Cc: Rafael Wysocki , linaro-kernel@lists.linaro.org, linux-pm@vger.kernel.org, skannan@codeaurora.org, peterz@infradead.org, mturquette@baylibre.com, steve.muckle@linaro.org, vincent.guittot@linaro.org, morten.rasmussen@arm.com, dietmar.eggemann@arm.com, linux-kernel@vger.kernel.org Subject: Re: [PATCH 0/5] cpufreq: governors: Solve the ABBA lockups Message-ID: <20160202112511.GB3947@e106622-lin> References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Viresh, On 02/02/16 16:27, Viresh Kumar wrote: > Hi Rafael, > > Sorry for doing this, I know you were also looking to fix this in a > possibly different way. But I thought, it would be better if we fix > that. We can scrap this version and take yours if that looks better. > > The root cause of all the issues we were facing, was that we were taking > policy->rwsem while accessing governor sysfs attributes. And that > happened because we were sharing the show/store calls present in > cpufreq.c. > > I thought, perhaps the best way to fix it is to give separate sysfs-ops > to governors. And that's what I did. > > @Juri: I need your help in testing these. My platform doesn't give me > those lockups (even without these patches) and Juno/Tc2 would fit > better. > > Can you please run some tests on these? > Sure! Will do in the next few days. Best, - Juri > They are pushed here for easy access (and auto test by build-bot): > git://git.kernel.org/pub/scm/linux/kernel/git/vireshk/pm.git cpufreq/governor-kobject > > -- > viresh > > Viresh Kumar (5): > cpufreq: governor: Kill declare_show_sampling_rate_min() > cpufreq: governor: Create separate sysfs-ops > cpufreq: governor: Remove unused sysfs attribute macros > cpufreq: Don't drop rwsem before calling CPUFREQ_GOV_POLICY_EXIT > cpufreq: Get rid of ->governor_enabled and its lock > > drivers/cpufreq/cpufreq.c | 29 ---------- > drivers/cpufreq/cpufreq_conservative.c | 77 ++++++++++--------------- > drivers/cpufreq/cpufreq_governor.c | 86 ++++++++++++++++++++-------- > drivers/cpufreq/cpufreq_governor.h | 101 +++++++-------------------------- > drivers/cpufreq/cpufreq_ondemand.c | 77 ++++++++++--------------- > include/linux/cpufreq.h | 5 -- > 6 files changed, 143 insertions(+), 232 deletions(-) > > -- > 2.7.0.79.gdc08a19 >