From mboxrd@z Thu Jan 1 00:00:00 1970 From: Viresh Kumar Subject: Re: [PATCH 0/3] cpufreq: governor: Fix potential races Date: Fri, 5 Jun 2015 08:30:28 +0530 Message-ID: <20150605030028.GB13999@linux> References: <556FDEA8.6090801@linux.vnet.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from mail-pd0-f174.google.com ([209.85.192.174]:35227 "EHLO mail-pd0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753504AbbFEDAd (ORCPT ); Thu, 4 Jun 2015 23:00:33 -0400 Received: by pdbnf5 with SMTP id nf5so43586673pdb.2 for ; Thu, 04 Jun 2015 20:00:33 -0700 (PDT) Content-Disposition: inline In-Reply-To: <556FDEA8.6090801@linux.vnet.ibm.com> Sender: linux-pm-owner@vger.kernel.org List-Id: linux-pm@vger.kernel.org To: Preeti U Murthy Cc: Rafael Wysocki , linaro-kernel@lists.linaro.org, linux-pm@vger.kernel.org, ego@linux.vnet.ibm.com, paulus@samba.org, shilpa.bhat@linux.vnet.ibm.com, prarit@redhat.com, robert.schoene@tu-dresden.de, skannan@codeaurora.org On 04-06-15, 10:44, Preeti U Murthy wrote: > On 06/03/2015 03:57 PM, Viresh Kumar wrote: > > Preeti recently highlighted [1] some issues in cpufreq core locking with > > respect to governors. I wanted to solve them after we have simplified > > the hotplug paths in cpufreq core with my latest patches, but now that > > she has poked me, I have done some work in that area. > > > > I am trying to solve only a part of the bigger problem (in a way that I > > feel is the right way ahead). The first patches restructures code to > > make it more readable and the last patch does all the major changes. The > > logs in that one should be good enough to explain why and what I am > > doing. > > > > The first two shouldn't bring any functional change and so can be > > applied early if you are confident about them. > > > > @Preeti: I would like you to test these patches. These should get rid of > > the crashes you were facing but may generate a WARN() from line 447 of > > cpufreq_governor.c, if the sequence is wrong. That has to be fixed > > separately. > > > > Line 447: WARN_ON(!dbs_data && (event != CPUFREQ_GOV_POLICY_INIT)) Hi Preeti, Thanks for giving your RBY tags for all the patches, would you also like to give Tested-by's if you have done any testing on these. That is just to confirm it hasn't broken things any further and that we haven't seen any crashes in races between INIT/EXIT/START/STOP/LIMITS. -- viresh