Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 18c49926 authored by Viresh Kumar's avatar Viresh Kumar Committed by Rafael J. Wysocki
Browse files

cpufreq: Add QoS requests for userspace constraints 



This implements QoS requests to manage userspace configuration of min
and max frequency.

Reviewed-by: default avatarMatthias Kaehlcke <mka@chromium.org>
Reviewed-by: default avatarUlf Hansson <ulf.hansson@linaro.org>
Signed-off-by: default avatarViresh Kumar <viresh.kumar@linaro.org>
Tested-by: default avatarsyzbot <syzbot+de771ae9390dffed7266@syzkaller.appspotmail.com>
Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
parent c57b25bd

drivers/cpufreq/cpufreq.c

+55 −43
Original line number Diff line number Diff line
@@ -718,23 +718,15 @@ static ssize_t show_scaling_cur_freq(struct cpufreq_policy *policy, char *buf) 
static ssize_t store_##file_name					\

(struct cpufreq_policy *policy, const char *buf, size_t count)		\

{									\

	int ret, temp;							\

	struct cpufreq_policy new_policy;				\

	unsigned long val;						\

	int ret;							\

									\

	memcpy(&new_policy, policy, sizeof(*policy));			\

	new_policy.min = policy->user_policy.min;			\

	new_policy.max = policy->user_policy.max;			\

									\

	ret = sscanf(buf, "%u", &new_policy.object);			\

	ret = sscanf(buf, "%lu", &val);					\

	if (ret != 1)							\

		return -EINVAL;						\

									\

	temp = new_policy.object;					\

	ret = cpufreq_set_policy(policy, &new_policy);		\

	if (!ret)							\

		policy->user_policy.object = temp;			\

									\

	return ret ? ret : count;					\

	ret = dev_pm_qos_update_request(policy->object##_freq_req, val);\

	return ret >= 0 ? count : ret;					\

}



store_one(scaling_min_freq, min);
@@ -1124,8 +1116,6 @@ void refresh_frequency_limits(struct cpufreq_policy *policy) 
		new_policy = *policy;

		pr_debug("updating policy for CPU %u\n", policy->cpu);



		new_policy.min = policy->user_policy.min;

		new_policy.max = policy->user_policy.max;

		cpufreq_set_policy(policy, &new_policy);

	}

}
@@ -1281,6 +1271,9 @@ static void cpufreq_policy_free(struct cpufreq_policy *policy) 
				   DEV_PM_QOS_MAX_FREQUENCY);

	dev_pm_qos_remove_notifier(dev, &policy->nb_min,

				   DEV_PM_QOS_MIN_FREQUENCY);

	dev_pm_qos_remove_request(policy->max_freq_req);

	dev_pm_qos_remove_request(policy->min_freq_req);

	kfree(policy->min_freq_req);



	cpufreq_policy_put_kobj(policy);

	free_cpumask_var(policy->real_cpus);
@@ -1359,16 +1352,50 @@ static int cpufreq_online(unsigned int cpu) 
	cpumask_and(policy->cpus, policy->cpus, cpu_online_mask);



	if (new_policy) {

		policy->user_policy.min = policy->min;

		policy->user_policy.max = policy->max;

		struct device *dev = get_cpu_device(cpu);



		for_each_cpu(j, policy->related_cpus) {

			per_cpu(cpufreq_cpu_data, j) = policy;

			add_cpu_dev_symlink(policy, j);

		}

	} else {

		policy->min = policy->user_policy.min;

		policy->max = policy->user_policy.max;



		policy->min_freq_req = kzalloc(2 * sizeof(*policy->min_freq_req),

					       GFP_KERNEL);

		if (!policy->min_freq_req)

			goto out_destroy_policy;



		ret = dev_pm_qos_add_request(dev, policy->min_freq_req,

					     DEV_PM_QOS_MIN_FREQUENCY,

					     policy->min);

		if (ret < 0) {

			/*

			 * So we don't call dev_pm_qos_remove_request() for an

			 * uninitialized request.

			 */

			kfree(policy->min_freq_req);

			policy->min_freq_req = NULL;



			dev_err(dev, "Failed to add min-freq constraint (%d)\n",

				ret);

			goto out_destroy_policy;

		}



		/*

		 * This must be initialized right here to avoid calling

		 * dev_pm_qos_remove_request() on uninitialized request in case

		 * of errors.

		 */

		policy->max_freq_req = policy->min_freq_req + 1;



		ret = dev_pm_qos_add_request(dev, policy->max_freq_req,

					     DEV_PM_QOS_MAX_FREQUENCY,

					     policy->max);

		if (ret < 0) {

			policy->max_freq_req = NULL;

			dev_err(dev, "Failed to add max-freq constraint (%d)\n",

				ret);

			goto out_destroy_policy;

		}

	}



	if (cpufreq_driver->get && has_target()) {
@@ -2342,7 +2369,6 @@ int cpufreq_set_policy(struct cpufreq_policy *policy, 
{

	struct cpufreq_governor *old_gov;

	struct device *cpu_dev = get_cpu_device(policy->cpu);

	unsigned long min, max;

	int ret;



	pr_debug("setting new policy for CPU %u: %u - %u kHz\n",
@@ -2350,24 +2376,12 @@ int cpufreq_set_policy(struct cpufreq_policy *policy, 


	memcpy(&new_policy->cpuinfo, &policy->cpuinfo, sizeof(policy->cpuinfo));



	/*

	* This check works well when we store new min/max freq attributes,

	* because new_policy is a copy of policy with one field updated.

	*/

	if (new_policy->min > new_policy->max)

		return -EINVAL;



	/*

	 * PM QoS framework collects all the requests from users and provide us

	 * the final aggregated value here.

	 */

	min = dev_pm_qos_read_value(cpu_dev, DEV_PM_QOS_MIN_FREQUENCY);

	max = dev_pm_qos_read_value(cpu_dev, DEV_PM_QOS_MAX_FREQUENCY);



	if (min > new_policy->min)

		new_policy->min = min;

	if (max < new_policy->max)

		new_policy->max = max;

	new_policy->min = dev_pm_qos_read_value(cpu_dev, DEV_PM_QOS_MIN_FREQUENCY);

	new_policy->max = dev_pm_qos_read_value(cpu_dev, DEV_PM_QOS_MAX_FREQUENCY);



	/* verify the cpu speed can be set within this limit */

	ret = cpufreq_driver->verify(new_policy);
@@ -2456,10 +2470,9 @@ int cpufreq_set_policy(struct cpufreq_policy *policy, 
 * @cpu: CPU to re-evaluate the policy for.

 *

 * Update the current frequency for the cpufreq policy of @cpu and use

 * cpufreq_set_policy() to re-apply the min and max limits saved in the

 * user_policy sub-structure of that policy, which triggers the evaluation

 * of policy notifiers and the cpufreq driver's ->verify() callback for the

 * policy in question, among other things.

 * cpufreq_set_policy() to re-apply the min and max limits, which triggers the

 * evaluation of policy notifiers and the cpufreq driver's ->verify() callback

 * for the policy in question, among other things.

 */

void cpufreq_update_policy(unsigned int cpu)

{
@@ -2519,10 +2532,9 @@ static int cpufreq_boost_set_sw(int state) 
			break;

		}



		down_write(&policy->rwsem);

		policy->user_policy.max = policy->max;

		cpufreq_governor_limits(policy);

		up_write(&policy->rwsem);

		ret = dev_pm_qos_update_request(policy->max_freq_req, policy->max);

		if (ret)

			break;

	}



	return ret;

include/linux/cpufreq.h

+2 −6
Original line number Diff line number Diff line
@@ -50,11 +50,6 @@ struct cpufreq_cpuinfo { 
	unsigned int		transition_latency;

};



struct cpufreq_user_policy {

	unsigned int		min;    /* in kHz */

	unsigned int		max;    /* in kHz */

};



struct cpufreq_policy {

	/* CPUs sharing clock, require sw coordination */

	cpumask_var_t		cpus;	/* Online CPUs only */
@@ -84,7 +79,8 @@ struct cpufreq_policy { 
	struct work_struct	update; /* if update_policy() needs to be

					 * called, but you're in IRQ context */



	struct cpufreq_user_policy user_policy;

	struct dev_pm_qos_request *min_freq_req;

	struct dev_pm_qos_request *max_freq_req;

	struct cpufreq_frequency_table	*freq_table;

	enum cpufreq_table_sorting freq_table_sorted;