linux-kernel - [PATCH V2 2/4] cpufreq: governor: Process remote callback for shared policies

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Date:   Thu, 29 Jun 2017 10:56:31 +0530
From:   Viresh Kumar <viresh.kumar@...aro.org>
To:     Rafael Wysocki <rjw@...ysocki.net>, Ingo Molnar <mingo@...hat.com>,
        Peter Zijlstra <peterz@...radead.org>,
        Viresh Kumar <viresh.kumar@...aro.org>
Cc:     linux-pm@...r.kernel.org,
        Vincent Guittot <vincent.guittot@...aro.org>,
        linux-kernel@...r.kernel.org, smuckle.linux@...il.com,
        juri.lelli@....com, Morten.Rasmussen@....com,
        patrick.bellasi@....com, eas-dev@...ts.linaro.org
Subject: [PATCH V2 2/4] cpufreq: governor: Process remote callback for shared policies

This patch updates the legacy governors (ondemand/conservative) to
process cpufreq utilization update hooks to be called for remote CPUs
(i.e. For updates to the runqueue of other non-local CPUs).

Based on initial work from Steve Muckle.

Signed-off-by: Viresh Kumar <viresh.kumar@...aro.org>
---
 drivers/cpufreq/cpufreq_governor.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/cpufreq/cpufreq_governor.c b/drivers/cpufreq/cpufreq_governor.c
index 47e24b5384b3..0b49fc8bb91d 100644
--- a/drivers/cpufreq/cpufreq_governor.c
+++ b/drivers/cpufreq/cpufreq_governor.c
@@ -275,6 +275,10 @@ static void dbs_update_util_handler(struct update_util_data *data, u64 time,
 	struct policy_dbs_info *policy_dbs = cdbs->policy_dbs;
 	u64 delta_ns, lst;
 
+	/* Allow remote callbacks only on the CPUs sharing cpufreq policy */
+	if (!cpumask_test_cpu(smp_processor_id(), policy_dbs->policy->cpus))
+		return;
+
 	/*
 	 * The work may not be allowed to be queued up right now.
 	 * Possible reasons:
-- 
2.13.0.71.gd7076ec9c9cb