From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S935158Ab3BTMFG (ORCPT ); Wed, 20 Feb 2013 07:05:06 -0500 Received: from mga02.intel.com ([134.134.136.20]:21275 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S935127Ab3BTMFE (ORCPT ); Wed, 20 Feb 2013 07:05:04 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.84,701,1355126400"; d="scan'208";a="265027913" Message-ID: <5124BBEA.3040806@intel.com> Date: Wed, 20 Feb 2013 20:04:58 +0800 From: Alex Shi User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:15.0) Gecko/20120912 Thunderbird/15.0.1 MIME-Version: 1.0 To: Peter Zijlstra CC: torvalds@linux-foundation.org, mingo@redhat.com, tglx@linutronix.de, akpm@linux-foundation.org, arjan@linux.intel.com, bp@alien8.de, pjt@google.com, namhyung@kernel.org, efault@gmx.de, vincent.guittot@linaro.org, gregkh@linuxfoundation.org, preeti@linux.vnet.ibm.com, viresh.kumar@linaro.org, linux-kernel@vger.kernel.org, morten.rasmussen@arm.com Subject: Re: [patch v5 11/15] sched: add power/performance balance allow flag References: <1361164062-20111-1-git-send-email-alex.shi@intel.com> <1361164062-20111-12-git-send-email-alex.shi@intel.com> <1361353681.10155.10.camel@laptop> In-Reply-To: <1361353681.10155.10.camel@laptop> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 02/20/2013 05:48 PM, Peter Zijlstra wrote: > On Mon, 2013-02-18 at 13:07 +0800, Alex Shi wrote: >> @@ -4053,6 +4053,8 @@ struct lb_env { >> unsigned int loop; >> unsigned int loop_break; >> unsigned int loop_max; >> + int power_lb; /* if power balance needed >> */ >> + int perf_lb; /* if performance balance >> needed */ >> }; >> >> /* >> @@ -5195,6 +5197,8 @@ static int load_balance(int this_cpu, struct rq >> *this_rq, >> .idle = idle, >> .loop_break = sched_nr_migrate_break, >> .cpus = cpus, >> + .power_lb = 0, >> + .perf_lb = 1, >> }; >> >> cpumask_copy(cpus, cpu_active_mask); > > This construct allows for the possibility of power_lb=1,perf_lb=1, does > that make sense? Why not have a single balance_policy enumeration? (power_lb == 1 && perf_lb == 1) is incorrect and impossible to have. (power_lb == 0 && perf_lb == 0) is possible and it means there is no any balance on this cpu. So, enumeration is not enough. > -- Thanks Alex