From mboxrd@z Thu Jan 1 00:00:00 1970 From: Saravana Kannan Subject: Re: [PATCH 04/18] cpufreq: Manage fallback policies in a list Date: Wed, 04 Feb 2015 17:55:02 -0800 Message-ID: <54D2CD76.2030609@codeaurora.org> References: <54D29D27.7080207@codeaurora.org> <6147604.f4mimnOd4x@vostro.rjw.lan> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from smtp.codeaurora.org ([198.145.11.231]:36897 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751297AbbBEBzG (ORCPT ); Wed, 4 Feb 2015 20:55:06 -0500 In-Reply-To: <6147604.f4mimnOd4x@vostro.rjw.lan> Sender: linux-pm-owner@vger.kernel.org List-Id: linux-pm@vger.kernel.org To: "Rafael J. Wysocki" Cc: Viresh Kumar , Linaro Kernel Mailman List , "linux-pm@vger.kernel.org" , Stephen Boyd , Prarit Bhargava On 02/04/2015 03:20 PM, Rafael J. Wysocki wrote: > On Wednesday, February 04, 2015 02:28:55 PM Saravana Kannan wrote: >> On 02/03/2015 10:20 PM, Viresh Kumar wrote: >>> On 4 February 2015 at 03:58, Saravana Kannan wrote: >>>> Can you explain why we need a fallback list in the first place? Now that we >>>> are not destroying and creating policy objects, I don't see any point in the >>>> fallback list. >>> >>> Because we wanted to mark the policy inactive. But as I have introduced another >>> field for that now, probably it can be fixed. Will check again on what >>> can be done. >> >> Thanks. That's why I was asking. Now that you have another flag. Also, >> you might not even need a flag. You can just check if policy->cpus is >> empty (btw, I think we should let that go to empty) > > So the idea would be to avoid clearig cpufreq_cpu_data during offline > tear-down (because we know that the CPU is offline anyway) and then start > using the same policy pointer during offline? Yeah. We still don't clear the policy->cpus today when the last CPU goes down. But that can be done easily by changing a few "if" conditions and rearranging the hotplug notifier code (I think it's mostly there with this series). Once we clear policy->cpus when all CPUs are offline, we can just use that data to figure out if it's "active" or not. -Saravana -- The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, hosted by The Linux Foundation