linux-kernel - [PATCH V4 3/3] cpufreq: governor: Process remote callback for shared policies

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Date:   Wed, 26 Jul 2017 14:52:34 +0530
From:   Viresh Kumar <viresh.kumar@...aro.org>
To:     Rafael Wysocki <rjw@...ysocki.net>,
        Viresh Kumar <viresh.kumar@...aro.org>
Cc:     linux-pm@...r.kernel.org,
        Vincent Guittot <vincent.guittot@...aro.org>,
        smuckle.linux@...il.com, juri.lelli@....com,
        Morten.Rasmussen@....com, patrick.bellasi@....com,
        eas-dev@...ts.linaro.org, linux-kernel@...r.kernel.org
Subject: [PATCH V4 3/3] 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.

Proper locking is already in place for shared policies and nothing extra
is required to be done.

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, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/cpufreq/cpufreq_governor.c b/drivers/cpufreq/cpufreq_governor.c
index 5499796cf9a8..b1bf84149526 100644
--- a/drivers/cpufreq/cpufreq_governor.c
+++ b/drivers/cpufreq/cpufreq_governor.c
@@ -272,8 +272,8 @@ 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;
 
-	/* Don't allow remote callbacks */
-	if (smp_processor_id() != data->cpu)
+	/* Allow remote callbacks only on the CPUs sharing cpufreq policy */
+	if (!cpumask_test_cpu(smp_processor_id(), policy_dbs->policy->cpus))
 		return;
 
 	/*
-- 
2.13.0.71.gd7076ec9c9cb