This implements QoS requests to manage userspace configuration of min and max frequency.
Signed-off-by: Viresh Kumar <[email protected]> --- drivers/cpufreq/cpufreq.c | 93 +++++++++++++++++++-------------------- include/linux/cpufreq.h | 8 +--- 2 files changed, 48 insertions(+), 53 deletions(-) diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c index d615bf35ac00..403e4540aea7 100644 --- a/drivers/cpufreq/cpufreq.c +++ b/drivers/cpufreq/cpufreq.c @@ -686,23 +686,15 @@ static int cpufreq_set_policy(struct cpufreq_policy *policy, 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 && ret != 1 ? ret : count; \ } store_one(scaling_min_freq, min); @@ -1089,10 +1081,6 @@ static void cpufreq_update_freq_work(struct work_struct *work) container_of(work, struct cpufreq_policy, req_work); struct cpufreq_policy new_policy = *policy; - /* We should read constraint values from QoS layer */ - new_policy.min = 0; - new_policy.max = UINT_MAX; - down_write(&policy->rwsem); if (!policy_is_inactive(policy)) @@ -1193,6 +1181,12 @@ static struct cpufreq_policy *cpufreq_policy_alloc(unsigned int cpu) goto err_min_qos_notifier; } + policy->min_freq_req = kzalloc(2 * sizeof(*policy->min_freq_req), + GFP_KERNEL); + if (!policy->min_freq_req) + goto err_max_qos_notifier; + + policy->max_freq_req = policy->min_freq_req + 1; INIT_LIST_HEAD(&policy->policy_list); init_rwsem(&policy->rwsem); spin_lock_init(&policy->transition_lock); @@ -1204,6 +1198,9 @@ static struct cpufreq_policy *cpufreq_policy_alloc(unsigned int cpu) policy->cpu = cpu; return policy; +err_max_qos_notifier: + dev_pm_qos_remove_notifier(dev, &policy->nb_max, + DEV_PM_QOS_MAX_FREQUENCY); err_min_qos_notifier: dev_pm_qos_remove_notifier(dev, &policy->nb_min, DEV_PM_QOS_MIN_FREQUENCY); @@ -1239,6 +1236,10 @@ 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); free_cpumask_var(policy->related_cpus); @@ -1316,16 +1317,30 @@ 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; + + ret = dev_pm_qos_add_request(dev, policy->min_freq_req, + DEV_PM_QOS_MIN_FREQUENCY, + policy->min); + if (ret < 0) { + dev_err(dev, "Failed to add min-freq constraint (%d)\n", + ret); + goto out_destroy_policy; + } + + ret = dev_pm_qos_add_request(dev, policy->max_freq_req, + DEV_PM_QOS_MAX_FREQUENCY, + policy->max); + if (ret < 0) { + dev_err(dev, "Failed to add max-freq constraint (%d)\n", + ret); + goto out_destroy_policy; + } } if (cpufreq_driver->get && !cpufreq_driver->setpolicy) { @@ -2315,7 +2330,6 @@ static 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", @@ -2323,20 +2337,9 @@ static 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; - - 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; + /* Start with min/max as seen by QoS framework */ + 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); @@ -2425,10 +2428,9 @@ static 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) { @@ -2453,8 +2455,6 @@ void cpufreq_update_policy(unsigned int cpu) pr_debug("updating policy for CPU %u\n", cpu); memcpy(&new_policy, policy, sizeof(*policy)); - new_policy.min = policy->user_policy.min; - new_policy.max = policy->user_policy.max; cpufreq_set_policy(policy, &new_policy); @@ -2485,10 +2485,9 @@ 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 f8f48d8a9b52..fc167a982c64 100644 --- a/include/linux/cpufreq.h +++ b/include/linux/cpufreq.h @@ -57,11 +57,6 @@ 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 */ @@ -92,7 +87,8 @@ struct cpufreq_policy { * called, but you're in IRQ context */ struct work_struct req_work; - 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; -- 2.21.0.rc0.269.g1a574e7a288b
