From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1032248AbeBPNrL (ORCPT ); Fri, 16 Feb 2018 08:47:11 -0500 Received: from bombadil.infradead.org ([198.137.202.133]:40276 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1032212AbeBPNrJ (ORCPT ); Fri, 16 Feb 2018 08:47:09 -0500 Date: Fri, 16 Feb 2018 14:47:04 +0100 From: Peter Zijlstra To: Morten Rasmussen Cc: mingo@redhat.com, valentin.schneider@arm.com, dietmar.eggemann@arm.com, vincent.guittot@linaro.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 1/7] sched: Add static_key for asymmetric cpu capacity optimizations Message-ID: <20180216134704.GE25201@hirez.programming.kicks-ass.net> References: <1518711654-23503-1-git-send-email-morten.rasmussen@arm.com> <1518711654-23503-2-git-send-email-morten.rasmussen@arm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1518711654-23503-2-git-send-email-morten.rasmussen@arm.com> User-Agent: Mutt/1.9.2 (2017-12-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Feb 15, 2018 at 04:20:48PM +0000, Morten Rasmussen wrote: > +static void update_asym_cpucapacity(int cpu) > +{ > + if (!static_branch_unlikely(&sched_asym_cpucapacity) && > + lowest_flag_domain(cpu, SD_ASYM_CPUCAPACITY)) > + static_branch_enable(&sched_asym_cpucapacity); > +} That looks odd, why not just: if (lowest_flag_domain(cpu, SD_ASYM_CPUCAPACITY)) static_branch_enable(&sched_asym_cpucapacity); ? possibly with: else static_branch_disable(&sched_asym_cpucapacity); if you want to play funny games :-)