Commit f6a7409c authored by Viresh Kumar's avatar Viresh Kumar Committed by Rafael J. Wysocki
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cpufreq: Notify governors when cpus are hot-[un]plugged 



Because cpufreq core and governors worry only about the online cpus, if a cpu is
hot [un]plugged, we must notify governors about it, otherwise be ready to expect
something unexpected.

We already have notifiers in the form of CPUFREQ_GOV_START/CPUFREQ_GOV_STOP, we
just need to call them now.

Signed-off-by: default avatarViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
parent 643ae6e8

drivers/cpufreq/cpufreq.c

+10 −0
Original line number Diff line number Diff line
@@ -751,11 +751,16 @@ static int cpufreq_add_dev_policy(unsigned int cpu, 
				return -EBUSY;

			}



			__cpufreq_governor(managed_policy, CPUFREQ_GOV_STOP);



			spin_lock_irqsave(&cpufreq_driver_lock, flags);

			cpumask_copy(managed_policy->cpus, policy->cpus);

			per_cpu(cpufreq_cpu_data, cpu) = managed_policy;

			spin_unlock_irqrestore(&cpufreq_driver_lock, flags);



			__cpufreq_governor(managed_policy, CPUFREQ_GOV_START);

			__cpufreq_governor(managed_policy, CPUFREQ_GOV_LIMITS);



			pr_debug("CPU already managed, adding link\n");

			ret = sysfs_create_link(&dev->kobj,

						&managed_policy->kobj,
@@ -1066,8 +1071,13 @@ static int __cpufreq_remove_dev(struct device *dev, struct subsys_interface *sif 
	 */

	if (unlikely(cpu != data->cpu)) {

		pr_debug("removing link\n");

		__cpufreq_governor(data, CPUFREQ_GOV_STOP);

		cpumask_clear_cpu(cpu, data->cpus);

		spin_unlock_irqrestore(&cpufreq_driver_lock, flags);



		__cpufreq_governor(data, CPUFREQ_GOV_START);

		__cpufreq_governor(data, CPUFREQ_GOV_LIMITS);



		kobj = &dev->kobj;

		cpufreq_cpu_put(data);

		unlock_policy_rwsem_write(cpu);

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