The patch below does not apply to the 5.2-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@xxxxxxxxxxxxxxx>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From 18c49926c4bf4915e5194d1de3299c0537229f9f Mon Sep 17 00:00:00 2001
From: Viresh Kumar <viresh.kumar@xxxxxxxxxx>
Date: Fri, 5 Jul 2019 16:21:24 +0530
Subject: [PATCH] cpufreq: Add QoS requests for userspace constraints
This implements QoS requests to manage userspace configuration of min
and max frequency.
Reviewed-by: Matthias Kaehlcke <mka@xxxxxxxxxxxx>
Reviewed-by: Ulf Hansson <ulf.hansson@xxxxxxxxxx>
Signed-off-by: Viresh Kumar <viresh.kumar@xxxxxxxxxx>
Tested-by: syzbot <syzbot+de771ae9390dffed7266@xxxxxxxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index 79bac52919a5..99aa7d20b458 100644
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -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;
diff --git a/include/linux/cpufreq.h b/include/linux/cpufreq.h
index 1fa37b675a80..afc683021ac5 100644
--- a/include/linux/cpufreq.h
+++ b/include/linux/cpufreq.h
@@ -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;
