diff --git a/drivers/cpufreq/cpufreq_conservative.c b/drivers/cpufreq/cpufreq_conservative.c index ed081dbce00c..6243502ce24d 100644 --- a/drivers/cpufreq/cpufreq_conservative.c +++ b/drivers/cpufreq/cpufreq_conservative.c @@ -136,20 +136,6 @@ static ssize_t store_sampling_down_factor(struct dbs_data *dbs_data, return count; } -static ssize_t store_sampling_rate(struct dbs_data *dbs_data, const char *buf, - size_t count) -{ - unsigned int input; - int ret; - ret = sscanf(buf, "%u", &input); - - if (ret != 1) - return -EINVAL; - - dbs_data->sampling_rate = max(input, dbs_data->min_sampling_rate); - return count; -} - static ssize_t store_up_threshold(struct dbs_data *dbs_data, const char *buf, size_t count) { diff --git a/drivers/cpufreq/cpufreq_governor.c b/drivers/cpufreq/cpufreq_governor.c index a34de9d10cbc..d41db19a9bb7 100644 --- a/drivers/cpufreq/cpufreq_governor.c +++ b/drivers/cpufreq/cpufreq_governor.c @@ -25,6 +25,69 @@ DEFINE_MUTEX(dbs_data_mutex); EXPORT_SYMBOL_GPL(dbs_data_mutex); +/* Common sysfs tunables */ +/** + * store_sampling_rate - update sampling rate effective immediately if needed. + * + * If new rate is smaller than the old, simply updating + * dbs.sampling_rate might not be appropriate. For example, if the + * original sampling_rate was 1 second and the requested new sampling rate is 10 + * ms because the user needs immediate reaction from ondemand governor, but not + * sure if higher frequency will be required or not, then, the governor may + * change the sampling rate too late; up to 1 second later. Thus, if we are + * reducing the sampling rate, we need to make the new value effective + * immediately. + * + * On the other hand, if new rate is larger than the old, then we may evaluate + * the load too soon, and it might we worth updating sample_delay_ns then as + * well. + * + * This must be called with dbs_data->mutex held, otherwise traversing + * policy_dbs_list isn't safe. + */ +ssize_t store_sampling_rate(struct dbs_data *dbs_data, const char *buf, + size_t count) +{ + struct policy_dbs_info *policy_dbs; + unsigned int rate; + int ret; + ret = sscanf(buf, "%u", &rate); + if (ret != 1) + return -EINVAL; + + dbs_data->sampling_rate = max(rate, dbs_data->min_sampling_rate); + + /* + * We are operating under dbs_data->mutex and so the list and its + * entries can't be freed concurrently. + */ + list_for_each_entry(policy_dbs, &dbs_data->policy_dbs_list, list) { + mutex_lock(&policy_dbs->timer_mutex); + /* + * On 32-bit architectures this may race with the + * sample_delay_ns read in dbs_update_util_handler(), but that + * really doesn't matter. If the read returns a value that's + * too big, the sample will be skipped, but the next invocation + * of dbs_update_util_handler() (when the update has been + * completed) will take a sample. If the returned value is too + * small, the sample will be taken immediately, but that isn't a + * problem, as we want the new rate to take effect immediately + * anyway. + * + * If this runs in parallel with dbs_work_handler(), we may end + * up overwriting the sample_delay_ns value that it has just + * written, but the difference should not be too big and it will + * be corrected next time a sample is taken, so it shouldn't be + * significant. + */ + gov_update_sample_delay(policy_dbs, dbs_data->sampling_rate); + mutex_unlock(&policy_dbs->timer_mutex); + } + + return count; +} +EXPORT_SYMBOL_GPL(store_sampling_rate); + static inline struct dbs_data *to_dbs_data(struct kobject *kobj) { return container_of(kobj, struct dbs_data, kobj); diff --git a/drivers/cpufreq/cpufreq_governor.h b/drivers/cpufreq/cpufreq_governor.h index e9ec411042c3..8138eff5e25b 100644 --- a/drivers/cpufreq/cpufreq_governor.h +++ b/drivers/cpufreq/cpufreq_governor.h @@ -238,4 +238,6 @@ void od_register_powersave_bias_handler(unsigned int (*f) (struct cpufreq_policy *, unsigned int, unsigned int), unsigned int powersave_bias); void od_unregister_powersave_bias_handler(void); +ssize_t store_sampling_rate(struct dbs_data *dbs_data, const char *buf, + size_t count); #endif /* _CPUFREQ_GOVERNOR_H */ diff --git a/drivers/cpufreq/cpufreq_ondemand.c b/drivers/cpufreq/cpufreq_ondemand.c index 38301c6b31c7..12213823cc93 100644 --- a/drivers/cpufreq/cpufreq_ondemand.c +++ b/drivers/cpufreq/cpufreq_ondemand.c @@ -221,75 +221,6 @@ static unsigned int od_dbs_timer(struct cpufreq_policy *policy) /************************** sysfs interface ************************/ static struct dbs_governor od_dbs_gov; -/** - * update_sampling_rate - update sampling rate effective immediately if needed. - * @new_rate: new sampling rate - * - * If new rate is smaller than the old, simply updating - * dbs.sampling_rate might not be appropriate. For example, if the - * original sampling_rate was 1 second and the requested new sampling rate is 10 - * ms because the user needs immediate reaction from ondemand governor, but not - * sure if higher frequency will be required or not, then, the governor may - * change the sampling rate too late; up to 1 second later. Thus, if we are - * reducing the sampling rate, we need to make the new value effective - * immediately. - * - * On the other hand, if new rate is larger than the old, then we may evaluate - * the load too soon, and it might we worth updating sample_delay_ns then as - * well. - * - * This must be called with dbs_data->mutex held, otherwise traversing - * policy_dbs_list isn't safe. - */ -static void update_sampling_rate(struct dbs_data *dbs_data, - unsigned int new_rate) -{ - struct policy_dbs_info *policy_dbs; - - dbs_data->sampling_rate = new_rate = max(new_rate, - dbs_data->min_sampling_rate); - - /* - * We are operating under dbs_data->mutex and so the list and its - * entries can't be freed concurrently. - */ - list_for_each_entry(policy_dbs, &dbs_data->policy_dbs_list, list) { - mutex_lock(&policy_dbs->timer_mutex); - /* - * On 32-bit architectures this may race with the - * sample_delay_ns read in dbs_update_util_handler(), but that - * really doesn't matter. If the read returns a value that's - * too big, the sample will be skipped, but the next invocation - * of dbs_update_util_handler() (when the update has been - * completed) will take a sample. If the returned value is too - * small, the sample will be taken immediately, but that isn't a - * problem, as we want the new rate to take effect immediately - * anyway. - * - * If this runs in parallel with dbs_work_handler(), we may end - * up overwriting the sample_delay_ns value that it has just - * written, but the difference should not be too big and it will - * be corrected next time a sample is taken, so it shouldn't be - * significant. - */ - gov_update_sample_delay(policy_dbs, new_rate); - mutex_unlock(&policy_dbs->timer_mutex); - } -} - -static ssize_t store_sampling_rate(struct dbs_data *dbs_data, const char *buf, - size_t count) -{ - unsigned int input; - int ret; - ret = sscanf(buf, "%u", &input); - if (ret != 1) - return -EINVAL; - - update_sampling_rate(dbs_data, input); - return count; -} - static ssize_t store_io_is_busy(struct dbs_data *dbs_data, const char *buf, size_t count) {