From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.3 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_MUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id E4B66C43441 for ; Wed, 21 Nov 2018 13:08:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id AA27A214C4 for ; Wed, 21 Nov 2018 13:08:44 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="sjm+e+Og" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org AA27A214C4 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730857AbeKUXnB (ORCPT ); Wed, 21 Nov 2018 18:43:01 -0500 Received: from merlin.infradead.org ([205.233.59.134]:47440 "EHLO merlin.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726016AbeKUXnB (ORCPT ); Wed, 21 Nov 2018 18:43:01 -0500 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=merlin.20170209; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=nCG+jXX8uNGqlqqoFESCKSdkKidtBODjCyXtca2k2vI=; b=sjm+e+OgG33mFjMDdbgTBF+fL 8ZSygXW4okVCuqU4/aU0I8uReiVYSQgjBEjvVXht3qfXuiOMc54RkRlc8OPfGYjo7aysEg803z4/Y zIoSjdG6FHUw+kXR0r3NpqoB2mreU4y/km+jfpo2jQntY8Ej90eqDXVns3UUuvY7A6Oe8ANG2td8J YKotM7YZeR1SvnDhQLWgpwxuJkCtXpjK/f8TFwMIf2+5zQmhDYq5GkWQbjyS8/+asirWsQKkakg0/ GtRDqZQfAARQYywoVqSLwemDXj04wQG8MX9YdPpX+1syurT4HQhlJU0oQYaLjd6qBmwRjBF49hzlJ KtdX2slwA==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=hirez.programming.kicks-ass.net) by merlin.infradead.org with esmtpsa (Exim 4.90_1 #2 (Red Hat Linux)) id 1gPSEz-0006HP-JL; Wed, 21 Nov 2018 13:08:25 +0000 Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id B8C972029FD58; Wed, 21 Nov 2018 14:08:22 +0100 (CET) Date: Wed, 21 Nov 2018 14:08:22 +0100 From: Peter Zijlstra To: Quentin Perret Cc: rjw@rjwysocki.net, linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org, gregkh@linuxfoundation.org, mingo@redhat.com, dietmar.eggemann@arm.com, morten.rasmussen@arm.com, chris.redpath@arm.com, patrick.bellasi@arm.com, valentin.schneider@arm.com, vincent.guittot@linaro.org, thara.gopinath@linaro.org, viresh.kumar@linaro.org, tkjos@google.com, joel@joelfernandes.org, smuckle@google.com, adharmap@codeaurora.org, skannan@codeaurora.org, pkondeti@codeaurora.org, juri.lelli@redhat.com, edubezval@gmail.com, srinivas.pandruvada@linux.intel.com, currojerez@riseup.net, javi.merino@kernel.org Subject: Re: [PATCH v9 09/15] sched: Introduce sched_energy_present static key Message-ID: <20181121130822.GE2113@hirez.programming.kicks-ass.net> References: <20181119141857.8625-1-quentin.perret@arm.com> <20181119141857.8625-10-quentin.perret@arm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20181119141857.8625-10-quentin.perret@arm.com> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Nov 19, 2018 at 02:18:51PM +0000, Quentin Perret wrote: > +static void sched_energy_start(int ndoms_new, cpumask_var_t doms_new[]) > +{ > + /* > + * The conditions for EAS to start are checked during the creation of > + * root domains. If one of them meets all conditions, it will have a > + * non-null list of performance domains. > + */ > + while (ndoms_new) { > + if (cpu_rq(cpumask_first(doms_new[ndoms_new - 1]))->rd->pd) > + goto enable; > + ndoms_new--; > + } That seems quite ugly; can't you simply return a bool from build_perf_domains() ? Something like the below, but less fugly ;-) --- a/kernel/sched/topology.c +++ b/kernel/sched/topology.c @@ -299,7 +299,7 @@ static void destroy_perf_domain_rcu(stru #define EM_MAX_COMPLEXITY 2048 extern struct cpufreq_governor schedutil_gov; -static void build_perf_domains(const struct cpumask *cpu_map) +static bool build_perf_domains(const struct cpumask *cpu_map) { int i, nr_pd = 0, nr_cs = 0, nr_cpus = cpumask_weight(cpu_map); struct perf_domain *pd = NULL, *tmp; @@ -365,7 +365,7 @@ static void build_perf_domains(const str if (tmp) call_rcu(&tmp->rcu, destroy_perf_domain_rcu); - return; + return !!pd; free: free_pd(pd); @@ -373,6 +373,8 @@ static void build_perf_domains(const str rcu_assign_pointer(rd->pd, NULL); if (tmp) call_rcu(&tmp->rcu, destroy_perf_domain_rcu); + + return false; } #else static void free_pd(struct perf_domain *pd) { } @@ -2173,6 +2175,9 @@ void partition_sched_domains(int ndoms_n } #if defined(CONFIG_ENERGY_MODEL) && defined(CONFIG_CPU_FREQ_GOV_SCHEDUTIL) + { + bool has_eas = false; + /* Build perf. domains: */ for (i = 0; i < ndoms_new; i++) { for (j = 0; j < n && !sched_energy_update; j++) { @@ -2181,10 +2186,13 @@ void partition_sched_domains(int ndoms_n goto match3; } /* No match - add perf. domains for a new rd */ - build_perf_domains(doms_new[i]); + has_eas |= build_perf_domains(doms_new[i]); match3: ; } + + sched_energy_set(has_eas); + } #endif /* Remember the new sched domains: */