From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932296AbdCILqD (ORCPT ); Thu, 9 Mar 2017 06:46:03 -0500 Received: from mail-pg0-f48.google.com ([74.125.83.48]:36400 "EHLO mail-pg0-f48.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932258AbdCILp7 (ORCPT ); Thu, 9 Mar 2017 06:45:59 -0500 From: Viresh Kumar To: Rafael Wysocki , Ingo Molnar , Peter Zijlstra Cc: linaro-kernel@lists.linaro.org, linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org, Vincent Guittot , smuckle.linux@gmail.com, juri.lelli@arm.com, Morten.Rasmussen@arm.com, patrick.bellasi@arm.com, eas-dev@lists.linaro.org, Viresh Kumar Subject: [RFC 6/9] sched: cpufreq: detect, process remote callbacks Date: Thu, 9 Mar 2017 17:15:16 +0530 Message-Id: <2e807adcbf0d5136876f9de48c62e9e2dd2a5b06.1489058244.git.viresh.kumar@linaro.org> X-Mailer: git-send-email 2.7.1.410.g6faf27b In-Reply-To: References: In-Reply-To: References: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Steve Muckle A callback is considered remote if the target CPU is not the current CPU and if it is not managed by the policy managing the current CPU or the current CPU can't do DVFS on its behalf. Queue the irq work for remote callbacks on the destination CPU. The irq work will carry out the fast or slow switch as appropriate. Signed-off-by: Steve Muckle [ vk: commit log, code cleanups, introduce dvfs_possible_from_any_cpu and drop late callback support to avoid IPIs on remote CPUs. ] Signed-off-by: Viresh Kumar --- kernel/sched/cpufreq_schedutil.c | 40 +++++++++++++++++++++++++++++++++++----- 1 file changed, 35 insertions(+), 5 deletions(-) diff --git a/kernel/sched/cpufreq_schedutil.c b/kernel/sched/cpufreq_schedutil.c index b168c31f1c8f..9bad579b6b08 100644 --- a/kernel/sched/cpufreq_schedutil.c +++ b/kernel/sched/cpufreq_schedutil.c @@ -100,11 +100,11 @@ static void sugov_fast_switch(struct cpufreq_policy *policy, } static void sugov_update_commit(struct sugov_policy *sg_policy, u64 time, - unsigned int next_freq) + int cpu, bool remote, unsigned int next_freq) { struct cpufreq_policy *policy = sg_policy->policy; - if (policy->fast_switch_enabled) { + if (policy->fast_switch_enabled && !remote) { if (sg_policy->next_freq == next_freq) { trace_cpu_frequency(policy->cur, policy->cpu); return; @@ -116,7 +116,7 @@ static void sugov_update_commit(struct sugov_policy *sg_policy, u64 time, sg_policy->next_freq = next_freq; sg_policy->last_freq_update_time = time; sg_policy->work_in_progress = true; - irq_work_queue(&sg_policy->irq_work); + irq_work_queue_on(&sg_policy->irq_work, cpu); } } @@ -206,6 +206,20 @@ static void sugov_update_single(struct update_util_data *hook, u64 time, struct cpufreq_policy *policy = sg_policy->policy; unsigned long util, max; unsigned int next_f; + int cpu, this_cpu = smp_processor_id(); + bool remote; + + if (policy->dvfs_possible_from_any_cpu) { + /* + * Avoid sending IPI to 'hook->cpu' if this CPU can change + * frequency on its behalf. + */ + remote = false; + cpu = this_cpu; + } else { + cpu = hook->cpu; + remote = this_cpu != hook->cpu; + } sugov_set_iowait_boost(sg_cpu, time, flags); sg_cpu->last_update = time; @@ -220,7 +234,7 @@ static void sugov_update_single(struct update_util_data *hook, u64 time, sugov_iowait_boost(sg_cpu, &util, &max); next_f = get_next_freq(sg_policy, util, max); } - sugov_update_commit(sg_policy, time, next_f); + sugov_update_commit(sg_policy, time, cpu, remote, next_f); } static unsigned int sugov_next_freq_shared(struct sugov_cpu *sg_cpu) @@ -269,8 +283,24 @@ static void sugov_update_shared(struct update_util_data *hook, u64 time, { struct sugov_cpu *sg_cpu = container_of(hook, struct sugov_cpu, update_util); struct sugov_policy *sg_policy = sg_cpu->sg_policy; + struct cpufreq_policy *policy = sg_policy->policy; unsigned long util, max; unsigned int next_f; + int cpu, this_cpu = smp_processor_id(); + bool remote; + + if (policy->dvfs_possible_from_any_cpu || + cpumask_test_cpu(this_cpu, policy->cpus)) { + /* + * Avoid sending IPI to 'hook->cpu' if this CPU can change + * frequency on its behalf. + */ + remote = false; + cpu = this_cpu; + } else { + cpu = hook->cpu; + remote = this_cpu != hook->cpu; + } sugov_get_util(&util, &max, hook->cpu); @@ -289,7 +319,7 @@ static void sugov_update_shared(struct update_util_data *hook, u64 time, else next_f = sugov_next_freq_shared(sg_cpu); - sugov_update_commit(sg_policy, time, next_f); + sugov_update_commit(sg_policy, time, cpu, remote, next_f); } raw_spin_unlock(&sg_policy->update_lock); -- 2.7.1.410.g6faf27b