Commit 3bc7dc83 authored Apr 07, 2016 by Rafael J. Wysocki Committed by Andres Oportus Feb 16, 2017

BACKPORT: cpufreq: Call cpufreq_disable_fast_switch() in sugov_exit()



Due to differences in the cpufreq core's handling of runtime CPU
offline and nonboot CPUs disabling during system suspend-to-RAM,
fast frequency switching gets disabled after a suspend-to-RAM and
resume cycle on all of the nonboot CPUs.

To prevent that from happening, move the invocation of
cpufreq_disable_fast_switch() from cpufreq_exit_governor() to
sugov_exit(), as the schedutil governor is the only user of fast
frequency switching today anyway.

That simply prevents cpufreq_disable_fast_switch() from being called
without invoking the ->governor callback for the CPUFREQ_GOV_POLICY_EXIT
event (which happens during system suspend now).

Fixes: b7898fda (cpufreq: Support for fast frequency switching)
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
(cherry picked from commit 6c9d9c81)

parent 5f6e85d7

kernel/sched/cpufreq_schedutil.c

+2 −0

Original line number	Diff line number	Diff line
		@@ -398,6 +398,8 @@ static int sugov_exit(struct cpufreq_policy *policy)
		struct sugov_tunables *tunables = sg_policy->tunables;
		unsigned int count;

		cpufreq_disable_fast_switch(policy);

		mutex_lock(&global_tunables_lock);

		count = gov_attr_set_put(&tunables->attr_set, &sg_policy->tunables_hook);