Commit f9ba680d authored by Srivatsa S. Bhat's avatar Srivatsa S. Bhat Committed by Rafael J. Wysocki
Browse files

cpufreq: Extract the handover of policy cpu to a helper function 



During cpu offline, when the policy->cpu is going down, some other CPU
present in the policy->cpus mask is nominated as the new policy->cpu.
Extract this functionality from __cpufreq_remove_dev() and implement
it in a helper function. This helps in upcoming code reorganization.

Signed-off-by: default avatarSrivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Acked-by: default avatarViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
parent e18f1682

drivers/cpufreq/cpufreq.c

+39 −24
Original line number Diff line number Diff line
@@ -1129,6 +1129,38 @@ static void update_policy_cpu(struct cpufreq_policy *policy, unsigned int cpu) 
			CPUFREQ_UPDATE_POLICY_CPU, policy);

}



static int cpufreq_nominate_new_policy_cpu(struct cpufreq_policy *data,

					   unsigned int old_cpu)

{

	struct device *cpu_dev;

	unsigned long flags;

	int ret;



	/* first sibling now owns the new sysfs dir */

	cpu_dev = get_cpu_device(cpumask_first(data->cpus));

	sysfs_remove_link(&cpu_dev->kobj, "cpufreq");

	ret = kobject_move(&data->kobj, &cpu_dev->kobj);

	if (ret) {

		pr_err("%s: Failed to move kobj: %d", __func__, ret);



		WARN_ON(lock_policy_rwsem_write(old_cpu));

		cpumask_set_cpu(old_cpu, data->cpus);



		write_lock_irqsave(&cpufreq_driver_lock, flags);

		per_cpu(cpufreq_cpu_data, old_cpu) = data;

		write_unlock_irqrestore(&cpufreq_driver_lock, flags);



		unlock_policy_rwsem_write(old_cpu);



		ret = sysfs_create_link(&cpu_dev->kobj, &data->kobj,

					"cpufreq");



		return -EINVAL;

	}



	return cpu_dev->id;

}



/**

 * __cpufreq_remove_dev - remove a CPU device

 *
@@ -1139,12 +1171,12 @@ static void update_policy_cpu(struct cpufreq_policy *policy, unsigned int cpu) 
static int __cpufreq_remove_dev(struct device *dev,

		struct subsys_interface *sif)

{

	unsigned int cpu = dev->id, ret, cpus;

	unsigned int cpu = dev->id, cpus;

	int new_cpu;

	unsigned long flags;

	struct cpufreq_policy *data;

	struct kobject *kobj;

	struct completion *cmp;

	struct device *cpu_dev;



	pr_debug("%s: unregistering CPU %u\n", __func__, cpu);
@@ -1179,32 +1211,15 @@ static int __cpufreq_remove_dev(struct device *dev, 
	if (cpu != data->cpu) {

		sysfs_remove_link(&dev->kobj, "cpufreq");

	} else if (cpus > 1) {

		/* first sibling now owns the new sysfs dir */

		cpu_dev = get_cpu_device(cpumask_first(data->cpus));

		sysfs_remove_link(&cpu_dev->kobj, "cpufreq");

		ret = kobject_move(&data->kobj, &cpu_dev->kobj);

		if (ret) {

			pr_err("%s: Failed to move kobj: %d", __func__, ret);



		new_cpu = cpufreq_nominate_new_policy_cpu(data, cpu);

		if (new_cpu >= 0) {

			WARN_ON(lock_policy_rwsem_write(cpu));

			cpumask_set_cpu(cpu, data->cpus);



			write_lock_irqsave(&cpufreq_driver_lock, flags);

			per_cpu(cpufreq_cpu_data, cpu) = data;

			write_unlock_irqrestore(&cpufreq_driver_lock, flags);



			update_policy_cpu(data, new_cpu);

			unlock_policy_rwsem_write(cpu);



			ret = sysfs_create_link(&cpu_dev->kobj, &data->kobj,

					"cpufreq");

			return -EINVAL;

			pr_debug("%s: policy Kobject moved to cpu: %d "

				 "from: %d\n",__func__, new_cpu, cpu);

		}



		WARN_ON(lock_policy_rwsem_write(cpu));

		update_policy_cpu(data, cpu_dev->id);

		unlock_policy_rwsem_write(cpu);

		pr_debug("%s: policy Kobject moved to cpu: %d from: %d\n",

				__func__, cpu_dev->id, cpu);

	}



	/* If cpu is last user of policy, free policy */

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