Commit 6c9d9c81 authored by Rafael J. Wysocki's avatar Rafael J. Wysocki
Browse files

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: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: default avatarViresh Kumar <viresh.kumar@linaro.org>
parent 9bdcb44e

drivers/cpufreq/cpufreq.c

+11 −8
Original line number Diff line number Diff line
@@ -77,7 +77,11 @@ static inline bool has_target(void) 
static int cpufreq_governor(struct cpufreq_policy *policy, unsigned int event);

static unsigned int __cpufreq_get(struct cpufreq_policy *policy);

static int cpufreq_start_governor(struct cpufreq_policy *policy);

static int cpufreq_exit_governor(struct cpufreq_policy *policy);



static inline int cpufreq_exit_governor(struct cpufreq_policy *policy)

{

	return cpufreq_governor(policy, CPUFREQ_GOV_POLICY_EXIT);

}



/**

 * Two notifier lists: the "policy" list is involved in the
@@ -482,7 +486,11 @@ void cpufreq_enable_fast_switch(struct cpufreq_policy *policy) 
}

EXPORT_SYMBOL_GPL(cpufreq_enable_fast_switch);



static void cpufreq_disable_fast_switch(struct cpufreq_policy *policy)

/**

 * cpufreq_disable_fast_switch - Disable fast frequency switching for policy.

 * @policy: cpufreq policy to disable fast frequency switching for.

 */

void cpufreq_disable_fast_switch(struct cpufreq_policy *policy)

{

	mutex_lock(&cpufreq_fast_switch_lock);

	if (policy->fast_switch_enabled) {
@@ -492,6 +500,7 @@ static void cpufreq_disable_fast_switch(struct cpufreq_policy *policy) 
	}

	mutex_unlock(&cpufreq_fast_switch_lock);

}

EXPORT_SYMBOL_GPL(cpufreq_disable_fast_switch);



/*********************************************************************

 *                          SYSFS INTERFACE                          *
@@ -2060,12 +2069,6 @@ static int cpufreq_start_governor(struct cpufreq_policy *policy) 
	return ret ? ret : cpufreq_governor(policy, CPUFREQ_GOV_LIMITS);

}



static int cpufreq_exit_governor(struct cpufreq_policy *policy)

{

	cpufreq_disable_fast_switch(policy);

	return cpufreq_governor(policy, CPUFREQ_GOV_POLICY_EXIT);

}



int cpufreq_register_governor(struct cpufreq_governor *governor)

{

	int err;

include/linux/cpufreq.h

+1 −0
Original line number Diff line number Diff line
@@ -168,6 +168,7 @@ int cpufreq_update_policy(unsigned int cpu); 
bool have_governor_per_policy(void);

struct kobject *get_governor_parent_kobj(struct cpufreq_policy *policy);

void cpufreq_enable_fast_switch(struct cpufreq_policy *policy);

void cpufreq_disable_fast_switch(struct cpufreq_policy *policy);

#else

static inline unsigned int cpufreq_get(unsigned int cpu)

{

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);

CRA Git | Maintained and supported by SUSTech CRA and CCSE