Commit fcccc5c8 authored by Kyle Lin's avatar Kyle Lin Committed by Rafael J. Wysocki
Browse files

cpufreq: stats: Use lock by stat to replace global spin lock 



Stats is updated by each policy, using the lock by stat can
reduce the contention.

Signed-off-by: default avatarKyle Lin <linkyle0915@gmail.com>
Acked-by: default avatarViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
parent 89f98d7e

drivers/cpufreq/cpufreq_stats.c

+8 −7
Original line number Original line Diff line number Diff line
@@ -14,7 +14,6 @@ 
#include <linux/module.h>

#include <linux/module.h>

#include <linux/slab.h>

#include <linux/slab.h>





static DEFINE_SPINLOCK(cpufreq_stats_lock);





struct cpufreq_stats {

struct cpufreq_stats {

	unsigned int total_trans;

	unsigned int total_trans;
@@ -23,6 +22,7 @@ struct cpufreq_stats { 
	unsigned int state_num;

	unsigned int state_num;

	unsigned int last_index;

	unsigned int last_index;

	u64 *time_in_state;

	u64 *time_in_state;

	spinlock_t lock;

	unsigned int *freq_table;

	unsigned int *freq_table;

	unsigned int *trans_table;

	unsigned int *trans_table;

};

};
@@ -39,12 +39,12 @@ static void cpufreq_stats_clear_table(struct cpufreq_stats *stats) 
{

{

	unsigned int count = stats->max_state;

	unsigned int count = stats->max_state;





	spin_lock(&cpufreq_stats_lock);

	spin_lock(&stats->lock);

	memset(stats->time_in_state, 0, count * sizeof(u64));

	memset(stats->time_in_state, 0, count * sizeof(u64));

	memset(stats->trans_table, 0, count * count * sizeof(int));

	memset(stats->trans_table, 0, count * count * sizeof(int));

	stats->last_time = get_jiffies_64();

	stats->last_time = get_jiffies_64();

	stats->total_trans = 0;

	stats->total_trans = 0;

	spin_unlock(&cpufreq_stats_lock);

	spin_unlock(&stats->lock);

}

}





static ssize_t show_total_trans(struct cpufreq_policy *policy, char *buf)

static ssize_t show_total_trans(struct cpufreq_policy *policy, char *buf)
@@ -62,9 +62,9 @@ static ssize_t show_time_in_state(struct cpufreq_policy *policy, char *buf) 
	if (policy->fast_switch_enabled)

	if (policy->fast_switch_enabled)

		return 0;

		return 0;





	spin_lock(&cpufreq_stats_lock);

	spin_lock(&stats->lock);

	cpufreq_stats_update(stats);

	cpufreq_stats_update(stats);

	spin_unlock(&cpufreq_stats_lock);

	spin_unlock(&stats->lock);





	for (i = 0; i < stats->state_num; i++) {

	for (i = 0; i < stats->state_num; i++) {

		len += sprintf(buf + len, "%u %llu\n", stats->freq_table[i],

		len += sprintf(buf + len, "%u %llu\n", stats->freq_table[i],
@@ -211,6 +211,7 @@ void cpufreq_stats_create_table(struct cpufreq_policy *policy) 
	stats->state_num = i;

	stats->state_num = i;

	stats->last_time = get_jiffies_64();

	stats->last_time = get_jiffies_64();

	stats->last_index = freq_table_get_index(stats, policy->cur);

	stats->last_index = freq_table_get_index(stats, policy->cur);

	spin_lock_init(&stats->lock);





	policy->stats = stats;

	policy->stats = stats;

	ret = sysfs_create_group(&policy->kobj, &stats_attr_group);

	ret = sysfs_create_group(&policy->kobj, &stats_attr_group);
@@ -242,11 +243,11 @@ void cpufreq_stats_record_transition(struct cpufreq_policy *policy, 
	if (old_index == -1 || new_index == -1 || old_index == new_index)

	if (old_index == -1 || new_index == -1 || old_index == new_index)

		return;

		return;





	spin_lock(&cpufreq_stats_lock);

	spin_lock(&stats->lock);

	cpufreq_stats_update(stats);

	cpufreq_stats_update(stats);





	stats->last_index = new_index;

	stats->last_index = new_index;

	stats->trans_table[old_index * stats->max_state + new_index]++;

	stats->trans_table[old_index * stats->max_state + new_index]++;

	stats->total_trans++;

	stats->total_trans++;

	spin_unlock(&cpufreq_stats_lock);

	spin_unlock(&stats->lock);

}
 
}

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