Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756072AbbDIWtb (ORCPT ); Thu, 9 Apr 2015 18:49:31 -0400 Received: from g2t2353.austin.hp.com ([15.217.128.52]:50717 "EHLO g2t2353.austin.hp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754841AbbDIWt3 (ORCPT ); Thu, 9 Apr 2015 18:49:29 -0400 Message-ID: <1428619765.12911.24.camel@j-VirtualBox> Subject: Re: sched: Improve load balancing in the presence of idle CPUs From: Jason Low To: Srikar Dronamraju Cc: Preeti U Murthy , Morten Rasmussen , "peterz@infradead.org" , "mingo@kernel.org" , Daniel Lezcano , "riel@redhat.com" , "vincent.guittot@linaro.org" , "pjt@google.com" , "benh@kernel.crashing.org" , "efault@gmx.de" , "linux-kernel@vger.kernel.org" , "iamjoonsoo.kim@lge.com" , "svaidy@linux.vnet.ibm.com" , "tim.c.chen@linux.intel.com" , jason.low2@hp.com Date: Thu, 09 Apr 2015 15:49:25 -0700 In-Reply-To: <20150409070220.GA10331@linux.vnet.ibm.com> References: <551A5CCE.70008@linux.vnet.ibm.com> <1427828056.2492.24.camel@j-VirtualBox> <551B9514.80701@linux.vnet.ibm.com> <20150401170418.GX18994@e105550-lin.cambridge.arm.com> <1427954347.2556.43.camel@j-VirtualBox> <551FB5F5.5050906@linux.vnet.ibm.com> <1428449300.2556.79.camel@j-VirtualBox> <1428451666.2556.84.camel@j-VirtualBox> <20150408111216.GA24645@linux.vnet.ibm.com> <1428547155.3506.42.camel@j-VirtualBox> <20150409070220.GA10331@linux.vnet.ibm.com> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.2.3-0ubuntu6 Content-Transfer-Encoding: 7bit Mime-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1005 Lines: 22 On Thu, 2015-04-09 at 12:32 +0530, Srikar Dronamraju wrote: > rq->idle_balance gets updated at every scheduler_tick() but the only user of > rq->idle_balance (after your change) seems to be run_rebalance_domains(). > Now can we remove rq->idle_balance. This would mean we would have to > call idle_cpu() instead of using rq->idle_balance in > run_rebalance_domains(). (similar to what your above change) > > That way we can reduce the rq struct size and we might end up calling > idle_cpu() lesser number of times. Yeah, we may also include another patch for that. Taking a look at rebalance_domains(), we're already updating the "idle" value using idle_cpu() after attempting load balancing anyway, so there may not be much point in the extra parameter. -- 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/