Commit 505b308b authored by Rafael J. Wysocki's avatar Rafael J. Wysocki
Browse files

Merge branch 'pm-cpufreq' 

* pm-cpufreq:
  cpufreq: Avoid leaving stale IRQ work items during CPU offline
parents 4c84515d 85572c2c

include/linux/cpufreq.h

+0 −11
Original line number Diff line number Diff line
@@ -595,17 +595,6 @@ struct governor_attr { 
			 size_t count);

};



static inline bool cpufreq_this_cpu_can_update(struct cpufreq_policy *policy)

{

	/*

	 * Allow remote callbacks if:

	 * - dvfs_possible_from_any_cpu flag is set

	 * - the local and remote CPUs share cpufreq policy

	 */

	return policy->dvfs_possible_from_any_cpu ||

		cpumask_test_cpu(smp_processor_id(), policy->cpus);

}



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

 *                     FREQUENCY TABLE HELPERS                       *

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

include/linux/sched/cpufreq.h

+3 −0
Original line number Diff line number Diff line
@@ -12,6 +12,8 @@ 
#define SCHED_CPUFREQ_MIGRATION	(1U << 1)



#ifdef CONFIG_CPU_FREQ

struct cpufreq_policy;



struct update_util_data {

       void (*func)(struct update_util_data *data, u64 time, unsigned int flags);

};
@@ -20,6 +22,7 @@ void cpufreq_add_update_util_hook(int cpu, struct update_util_data *data, 
                       void (*func)(struct update_util_data *data, u64 time,

				    unsigned int flags));

void cpufreq_remove_update_util_hook(int cpu);

bool cpufreq_this_cpu_can_update(struct cpufreq_policy *policy);



static inline unsigned long map_util_freq(unsigned long util,

					unsigned long freq, unsigned long cap)

kernel/sched/cpufreq.c

+18 −0
Original line number Diff line number Diff line
@@ -5,6 +5,8 @@ 
 * Copyright (C) 2016, Intel Corporation

 * Author: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

 */

#include <linux/cpufreq.h>



#include "sched.h"



DEFINE_PER_CPU(struct update_util_data __rcu *, cpufreq_update_util_data);
@@ -57,3 +59,19 @@ void cpufreq_remove_update_util_hook(int cpu) 
	rcu_assign_pointer(per_cpu(cpufreq_update_util_data, cpu), NULL);

}

EXPORT_SYMBOL_GPL(cpufreq_remove_update_util_hook);



/**

 * cpufreq_this_cpu_can_update - Check if cpufreq policy can be updated.

 * @policy: cpufreq policy to check.

 *

 * Return 'true' if:

 * - the local and remote CPUs share @policy,

 * - dvfs_possible_from_any_cpu is set in @policy and the local CPU is not going

 *   offline (in which case it is not expected to run cpufreq updates any more).

 */

bool cpufreq_this_cpu_can_update(struct cpufreq_policy *policy)

{

	return cpumask_test_cpu(smp_processor_id(), policy->cpus) ||

		(policy->dvfs_possible_from_any_cpu &&

		 rcu_dereference_sched(*this_cpu_ptr(&cpufreq_update_util_data)));

}

kernel/sched/cpufreq_schedutil.c

+3 −5
Original line number Diff line number Diff line
@@ -82,12 +82,10 @@ static bool sugov_should_update_freq(struct sugov_policy *sg_policy, u64 time) 
	 * by the hardware, as calculating the frequency is pointless if

	 * we cannot in fact act on it.

	 *

	 * For the slow switching platforms, the kthread is always scheduled on

	 * the right set of CPUs and any CPU can find the next frequency and

	 * schedule the kthread.

	 * This is needed on the slow switching platforms too to prevent CPUs

	 * going offline from leaving stale IRQ work items behind.

	 */

	if (sg_policy->policy->fast_switch_enabled &&

	    !cpufreq_this_cpu_can_update(sg_policy->policy))

	if (!cpufreq_this_cpu_can_update(sg_policy->policy))

		return false;



	if (unlikely(sg_policy->limits_changed)) {