drivers/cpufreq/cpufreq_stats.c - kernel/msm-4.9 - Gitiles

 /*
  *  drivers/cpufreq/cpufreq_stats.c
  *
  *  Copyright (C) 2003-2004 Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>.
  *  (C) 2004 Zou Nan hai <nanhai.zou@intel.com>.
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 2 as
  * published by the Free Software Foundation.
  */

 #include <linux/cpu.h>
 #include <linux/cpufreq.h>
 #include <linux/module.h>
 #include <linux/slab.h>
 #include <linux/cputime.h>

 static spinlock_t cpufreq_stats_lock;

 struct cpufreq_stats {
 	unsigned int total_trans;
 	unsigned long long last_time;
 	unsigned int max_state;
 	unsigned int state_num;
 	unsigned int last_index;
 	u64 *time_in_state;
 	unsigned int *freq_table;
 #ifdef CONFIG_CPU_FREQ_STAT_DETAILS
 	unsigned int *trans_table;
 #endif
 };

 static int cpufreq_stats_update(struct cpufreq_stats *stats)
 {
 	unsigned long long cur_time = get_jiffies_64();

 	spin_lock(&cpufreq_stats_lock);
 	stats->time_in_state[stats->last_index] += cur_time - stats->last_time;
 	stats->last_time = cur_time;
 	spin_unlock(&cpufreq_stats_lock);
 	return 0;
 }

 static ssize_t show_total_trans(struct cpufreq_policy *policy, char *buf)
 {
 	return sprintf(buf, "%d\n", policy->stats->total_trans);
 }

 static ssize_t show_time_in_state(struct cpufreq_policy *policy, char *buf)
 {
 	struct cpufreq_stats *stats = policy->stats;
 	ssize_t len = 0;
 	int i;

 	cpufreq_stats_update(stats);
 	for (i = 0; i < stats->state_num; i++) {
 		len += sprintf(buf + len, "%u %llu\n", stats->freq_table[i],
 			(unsigned long long)
 			jiffies_64_to_clock_t(stats->time_in_state[i]));
 	}
 	return len;
 }

 #ifdef CONFIG_CPU_FREQ_STAT_DETAILS
 static ssize_t show_trans_table(struct cpufreq_policy *policy, char *buf)
 {
 	struct cpufreq_stats *stats = policy->stats;
 	ssize_t len = 0;
 	int i, j;

 	len += snprintf(buf + len, PAGE_SIZE - len, "   From  :    To\n");
 	len += snprintf(buf + len, PAGE_SIZE - len, "         : ");
 	for (i = 0; i < stats->state_num; i++) {
 		if (len >= PAGE_SIZE)
 			break;
 		len += snprintf(buf + len, PAGE_SIZE - len, "%9u ",
 				stats->freq_table[i]);
 	}
 	if (len >= PAGE_SIZE)
 		return PAGE_SIZE;

 	len += snprintf(buf + len, PAGE_SIZE - len, "\n");

 	for (i = 0; i < stats->state_num; i++) {
 		if (len >= PAGE_SIZE)
 			break;

 		len += snprintf(buf + len, PAGE_SIZE - len, "%9u: ",
 				stats->freq_table[i]);

 		for (j = 0; j < stats->state_num; j++) {
 			if (len >= PAGE_SIZE)
 				break;
 			len += snprintf(buf + len, PAGE_SIZE - len, "%9u ",
 					stats->trans_table[i*stats->max_state+j]);
 		}
 		if (len >= PAGE_SIZE)
 			break;
 		len += snprintf(buf + len, PAGE_SIZE - len, "\n");
 	}
 	if (len >= PAGE_SIZE)
 		return PAGE_SIZE;
 	return len;
 }
 cpufreq_freq_attr_ro(trans_table);
 #endif

 cpufreq_freq_attr_ro(total_trans);
 cpufreq_freq_attr_ro(time_in_state);

 static struct attribute *default_attrs[] = {
 	&total_trans.attr,
 	&time_in_state.attr,
 #ifdef CONFIG_CPU_FREQ_STAT_DETAILS
 	&trans_table.attr,
 #endif
 	NULL
 };
 static struct attribute_group stats_attr_group = {
 	.attrs = default_attrs,
 	.name = "stats"
 };

 static int freq_table_get_index(struct cpufreq_stats *stats, unsigned int freq)
 {
 	int index;
 	for (index = 0; index < stats->max_state; index++)
 		if (stats->freq_table[index] == freq)
 			return index;
 	return -1;
 }

 static void __cpufreq_stats_free_table(struct cpufreq_policy *policy)
 {
 	struct cpufreq_stats *stats = policy->stats;

 	/* Already freed */
 	if (!stats)
 		return;

 	pr_debug("%s: Free stats table\n", __func__);

 	sysfs_remove_group(&policy->kobj, &stats_attr_group);
 	kfree(stats->time_in_state);
 	kfree(stats);
 	policy->stats = NULL;
 }

 static void cpufreq_stats_free_table(unsigned int cpu)
 {
 	struct cpufreq_policy *policy;

 	policy = cpufreq_cpu_get(cpu);
 	if (!policy)
 		return;

 	__cpufreq_stats_free_table(policy);

 	cpufreq_cpu_put(policy);
 }

 static int __cpufreq_stats_create_table(struct cpufreq_policy *policy)
 {
 	unsigned int i = 0, count = 0, ret = -ENOMEM;
 	struct cpufreq_stats *stats;
 	unsigned int alloc_size;
 	unsigned int cpu = policy->cpu;
 	struct cpufreq_frequency_table *pos, *table;

 	/* We need cpufreq table for creating stats table */
 	table = cpufreq_frequency_get_table(cpu);
 	if (unlikely(!table))
 		return 0;

 	/* stats already initialized */
 	if (policy->stats)
 		return -EEXIST;

 	stats = kzalloc(sizeof(*stats), GFP_KERNEL);
 	if (!stats)
 		return -ENOMEM;

 	/* Find total allocation size */
 	cpufreq_for_each_valid_entry(pos, table)
 		count++;

 	alloc_size = count * sizeof(int) + count * sizeof(u64);

 #ifdef CONFIG_CPU_FREQ_STAT_DETAILS
 	alloc_size += count * count * sizeof(int);
 #endif

 	/* Allocate memory for time_in_state/freq_table/trans_table in one go */
 	stats->time_in_state = kzalloc(alloc_size, GFP_KERNEL);
 	if (!stats->time_in_state)
 		goto free_stat;

 	stats->freq_table = (unsigned int *)(stats->time_in_state + count);

 #ifdef CONFIG_CPU_FREQ_STAT_DETAILS
 	stats->trans_table = stats->freq_table + count;
 #endif

 	stats->max_state = count;

 	/* Find valid-unique entries */
 	cpufreq_for_each_valid_entry(pos, table)
 		if (freq_table_get_index(stats, pos->frequency) == -1)
 			stats->freq_table[i++] = pos->frequency;

 	stats->state_num = i;
 	stats->last_time = get_jiffies_64();
 	stats->last_index = freq_table_get_index(stats, policy->cur);

 	policy->stats = stats;
 	ret = sysfs_create_group(&policy->kobj, &stats_attr_group);
 	if (!ret)
 		return 0;

 	/* We failed, release resources */
 	policy->stats = NULL;
 	kfree(stats->time_in_state);
 free_stat:
 	kfree(stats);

 	return ret;
 }

 static void cpufreq_stats_create_table(unsigned int cpu)
 {
 	struct cpufreq_policy *policy;

 	/*
 	 * "likely(!policy)" because normally cpufreq_stats will be registered
 	 * before cpufreq driver
 	 */
 	policy = cpufreq_cpu_get(cpu);
 	if (likely(!policy))
 		return;

 	__cpufreq_stats_create_table(policy);

 	cpufreq_cpu_put(policy);
 }

 static int cpufreq_stat_notifier_policy(struct notifier_block *nb,
 		unsigned long val, void *data)
 {
 	int ret = 0;
 	struct cpufreq_policy *policy = data;

 	if (val == CPUFREQ_CREATE_POLICY)
 		ret = __cpufreq_stats_create_table(policy);
 	else if (val == CPUFREQ_REMOVE_POLICY)
 		__cpufreq_stats_free_table(policy);

 	return ret;
 }

 static int cpufreq_stat_notifier_trans(struct notifier_block *nb,
 		unsigned long val, void *data)
 {
 	struct cpufreq_freqs *freq = data;
 	struct cpufreq_policy *policy = cpufreq_cpu_get(freq->cpu);
 	struct cpufreq_stats *stats;
 	int old_index, new_index;

 	if (!policy) {
 		pr_err("%s: No policy found\n", __func__);
 		return 0;
 	}

 	if (val != CPUFREQ_POSTCHANGE)
 		goto put_policy;

 	if (!policy->stats) {
 		pr_debug("%s: No stats found\n", __func__);
 		goto put_policy;
 	}

 	stats = policy->stats;

 	old_index = stats->last_index;
 	new_index = freq_table_get_index(stats, freq->new);

 	/* We can't do stats->time_in_state[-1]= .. */
 	if (old_index == -1 || new_index == -1)
 		goto put_policy;

 	if (old_index == new_index)
 		goto put_policy;

 	cpufreq_stats_update(stats);

 	stats->last_index = new_index;
 #ifdef CONFIG_CPU_FREQ_STAT_DETAILS
 	stats->trans_table[old_index * stats->max_state + new_index]++;
 #endif
 	stats->total_trans++;

 put_policy:
 	cpufreq_cpu_put(policy);
 	return 0;
 }

 static struct notifier_block notifier_policy_block = {
 	.notifier_call = cpufreq_stat_notifier_policy
 };

 static struct notifier_block notifier_trans_block = {
 	.notifier_call = cpufreq_stat_notifier_trans
 };

 static int __init cpufreq_stats_init(void)
 {
 	int ret;
 	unsigned int cpu;

 	spin_lock_init(&cpufreq_stats_lock);
 	ret = cpufreq_register_notifier(&notifier_policy_block,
 				CPUFREQ_POLICY_NOTIFIER);
 	if (ret)
 		return ret;

 	for_each_online_cpu(cpu)
 		cpufreq_stats_create_table(cpu);

 	ret = cpufreq_register_notifier(&notifier_trans_block,
 				CPUFREQ_TRANSITION_NOTIFIER);
 	if (ret) {
 		cpufreq_unregister_notifier(&notifier_policy_block,
 				CPUFREQ_POLICY_NOTIFIER);
 		for_each_online_cpu(cpu)
 			cpufreq_stats_free_table(cpu);
 		return ret;
 	}

 	return 0;
 }
 static void __exit cpufreq_stats_exit(void)
 {
 	unsigned int cpu;

 	cpufreq_unregister_notifier(&notifier_policy_block,
 			CPUFREQ_POLICY_NOTIFIER);
 	cpufreq_unregister_notifier(&notifier_trans_block,
 			CPUFREQ_TRANSITION_NOTIFIER);
 	for_each_online_cpu(cpu)
 		cpufreq_stats_free_table(cpu);
 }

 MODULE_AUTHOR("Zou Nan hai <nanhai.zou@intel.com>");
 MODULE_DESCRIPTION("Export cpufreq stats via sysfs");
 MODULE_LICENSE("GPL");

 module_init(cpufreq_stats_init);
 module_exit(cpufreq_stats_exit);
	/*
	* drivers/cpufreq/cpufreq_stats.c
	*
	* Copyright (C) 2003-2004 Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>.
	* (C) 2004 Zou Nan hai <nanhai.zou@intel.com>.
	*
	* This program is free software; you can redistribute it and/or modify
	* it under the terms of the GNU General Public License version 2 as
	* published by the Free Software Foundation.
	*/

	#include <linux/cpu.h>
	#include <linux/cpufreq.h>
	#include <linux/module.h>
	#include <linux/slab.h>
	#include <linux/cputime.h>

	static spinlock_t cpufreq_stats_lock;

	struct cpufreq_stats {
	unsigned int total_trans;
	unsigned long long last_time;
	unsigned int max_state;
	unsigned int state_num;
	unsigned int last_index;
	u64 *time_in_state;
	unsigned int *freq_table;
	#ifdef CONFIG_CPU_FREQ_STAT_DETAILS
	unsigned int *trans_table;
	#endif
	};

	static int cpufreq_stats_update(struct cpufreq_stats *stats)
	{
	unsigned long long cur_time = get_jiffies_64();

	spin_lock(&cpufreq_stats_lock);
	stats->time_in_state[stats->last_index] += cur_time - stats->last_time;
	stats->last_time = cur_time;
	spin_unlock(&cpufreq_stats_lock);
	return 0;
	}

	static ssize_t show_total_trans(struct cpufreq_policy policy, char buf)
	{
	return sprintf(buf, "%d\n", policy->stats->total_trans);
	}

	static ssize_t show_time_in_state(struct cpufreq_policy policy, char buf)
	{
	struct cpufreq_stats *stats = policy->stats;
	ssize_t len = 0;
	int i;

	cpufreq_stats_update(stats);
	for (i = 0; i < stats->state_num; i++) {
	len += sprintf(buf + len, "%u %llu\n", stats->freq_table[i],
	(unsigned long long)
	jiffies_64_to_clock_t(stats->time_in_state[i]));
	}
	return len;
	}

	#ifdef CONFIG_CPU_FREQ_STAT_DETAILS
	static ssize_t show_trans_table(struct cpufreq_policy policy, char buf)
	{
	struct cpufreq_stats *stats = policy->stats;
	ssize_t len = 0;
	int i, j;

	len += snprintf(buf + len, PAGE_SIZE - len, " From : To\n");
	len += snprintf(buf + len, PAGE_SIZE - len, " : ");
	for (i = 0; i < stats->state_num; i++) {
	if (len >= PAGE_SIZE)
	break;
	len += snprintf(buf + len, PAGE_SIZE - len, "%9u ",
	stats->freq_table[i]);
	}
	if (len >= PAGE_SIZE)
	return PAGE_SIZE;

	len += snprintf(buf + len, PAGE_SIZE - len, "\n");

	for (i = 0; i < stats->state_num; i++) {
	if (len >= PAGE_SIZE)
	break;

	len += snprintf(buf + len, PAGE_SIZE - len, "%9u: ",
	stats->freq_table[i]);

	for (j = 0; j < stats->state_num; j++) {
	if (len >= PAGE_SIZE)
	break;
	len += snprintf(buf + len, PAGE_SIZE - len, "%9u ",
	stats->trans_table[i*stats->max_state+j]);
	}
	if (len >= PAGE_SIZE)
	break;
	len += snprintf(buf + len, PAGE_SIZE - len, "\n");
	}
	if (len >= PAGE_SIZE)
	return PAGE_SIZE;
	return len;
	}
	cpufreq_freq_attr_ro(trans_table);
	#endif

	cpufreq_freq_attr_ro(total_trans);
	cpufreq_freq_attr_ro(time_in_state);

	static struct attribute *default_attrs[] = {
	&total_trans.attr,
	&time_in_state.attr,
	#ifdef CONFIG_CPU_FREQ_STAT_DETAILS
	&trans_table.attr,
	#endif
	NULL
	};
	static struct attribute_group stats_attr_group = {
	.attrs = default_attrs,
	.name = "stats"
	};

	static int freq_table_get_index(struct cpufreq_stats *stats, unsigned int freq)
	{
	int index;
	for (index = 0; index < stats->max_state; index++)
	if (stats->freq_table[index] == freq)
	return index;
	return -1;
	}

	static void __cpufreq_stats_free_table(struct cpufreq_policy *policy)
	{
	struct cpufreq_stats *stats = policy->stats;

	/* Already freed */
	if (!stats)
	return;

	pr_debug("%s: Free stats table\n", __func__);

	sysfs_remove_group(&policy->kobj, &stats_attr_group);
	kfree(stats->time_in_state);
	kfree(stats);
	policy->stats = NULL;
	}

	static void cpufreq_stats_free_table(unsigned int cpu)
	{
	struct cpufreq_policy *policy;

	policy = cpufreq_cpu_get(cpu);
	if (!policy)
	return;

	__cpufreq_stats_free_table(policy);

	cpufreq_cpu_put(policy);
	}

	static int __cpufreq_stats_create_table(struct cpufreq_policy *policy)
	{
	unsigned int i = 0, count = 0, ret = -ENOMEM;
	struct cpufreq_stats *stats;
	unsigned int alloc_size;
	unsigned int cpu = policy->cpu;
	struct cpufreq_frequency_table pos, table;

	/* We need cpufreq table for creating stats table */
	table = cpufreq_frequency_get_table(cpu);
	if (unlikely(!table))
	return 0;

	/* stats already initialized */
	if (policy->stats)
	return -EEXIST;

	stats = kzalloc(sizeof(*stats), GFP_KERNEL);
	if (!stats)
	return -ENOMEM;

	/* Find total allocation size */
	cpufreq_for_each_valid_entry(pos, table)
	count++;

	alloc_size = count * sizeof(int) + count * sizeof(u64);

	#ifdef CONFIG_CPU_FREQ_STAT_DETAILS
	alloc_size += count * count * sizeof(int);
	#endif

	/* Allocate memory for time_in_state/freq_table/trans_table in one go */
	stats->time_in_state = kzalloc(alloc_size, GFP_KERNEL);
	if (!stats->time_in_state)
	goto free_stat;

	stats->freq_table = (unsigned int *)(stats->time_in_state + count);

	#ifdef CONFIG_CPU_FREQ_STAT_DETAILS
	stats->trans_table = stats->freq_table + count;
	#endif

	stats->max_state = count;

	/* Find valid-unique entries */
	cpufreq_for_each_valid_entry(pos, table)
	if (freq_table_get_index(stats, pos->frequency) == -1)
	stats->freq_table[i++] = pos->frequency;

	stats->state_num = i;
	stats->last_time = get_jiffies_64();
	stats->last_index = freq_table_get_index(stats, policy->cur);

	policy->stats = stats;
	ret = sysfs_create_group(&policy->kobj, &stats_attr_group);
	if (!ret)
	return 0;

	/* We failed, release resources */
	policy->stats = NULL;
	kfree(stats->time_in_state);
	free_stat:
	kfree(stats);

	return ret;
	}

	static void cpufreq_stats_create_table(unsigned int cpu)
	{
	struct cpufreq_policy *policy;

	/*
	* "likely(!policy)" because normally cpufreq_stats will be registered
	* before cpufreq driver
	*/
	policy = cpufreq_cpu_get(cpu);
	if (likely(!policy))
	return;

	__cpufreq_stats_create_table(policy);

	cpufreq_cpu_put(policy);
	}

	static int cpufreq_stat_notifier_policy(struct notifier_block *nb,
	unsigned long val, void *data)
	{
	int ret = 0;
	struct cpufreq_policy *policy = data;

	if (val == CPUFREQ_CREATE_POLICY)
	ret = __cpufreq_stats_create_table(policy);
	else if (val == CPUFREQ_REMOVE_POLICY)
	__cpufreq_stats_free_table(policy);

	return ret;
	}

	static int cpufreq_stat_notifier_trans(struct notifier_block *nb,
	unsigned long val, void *data)
	{
	struct cpufreq_freqs *freq = data;
	struct cpufreq_policy *policy = cpufreq_cpu_get(freq->cpu);
	struct cpufreq_stats *stats;
	int old_index, new_index;

	if (!policy) {
	pr_err("%s: No policy found\n", __func__);
	return 0;
	}

	if (val != CPUFREQ_POSTCHANGE)
	goto put_policy;

	if (!policy->stats) {
	pr_debug("%s: No stats found\n", __func__);
	goto put_policy;
	}

	stats = policy->stats;

	old_index = stats->last_index;
	new_index = freq_table_get_index(stats, freq->new);

	/* We can't do stats->time_in_state[-1]= .. */
	if (old_index == -1 \|\| new_index == -1)
	goto put_policy;

	if (old_index == new_index)
	goto put_policy;

	cpufreq_stats_update(stats);

	stats->last_index = new_index;
	#ifdef CONFIG_CPU_FREQ_STAT_DETAILS
	stats->trans_table[old_index * stats->max_state + new_index]++;
	#endif
	stats->total_trans++;

	put_policy:
	cpufreq_cpu_put(policy);
	return 0;
	}

	static struct notifier_block notifier_policy_block = {
	.notifier_call = cpufreq_stat_notifier_policy
	};

	static struct notifier_block notifier_trans_block = {
	.notifier_call = cpufreq_stat_notifier_trans
	};

	static int __init cpufreq_stats_init(void)
	{
	int ret;
	unsigned int cpu;

	spin_lock_init(&cpufreq_stats_lock);
	ret = cpufreq_register_notifier(&notifier_policy_block,
	CPUFREQ_POLICY_NOTIFIER);
	if (ret)
	return ret;

	for_each_online_cpu(cpu)
	cpufreq_stats_create_table(cpu);

	ret = cpufreq_register_notifier(&notifier_trans_block,
	CPUFREQ_TRANSITION_NOTIFIER);
	if (ret) {
	cpufreq_unregister_notifier(&notifier_policy_block,
	CPUFREQ_POLICY_NOTIFIER);
	for_each_online_cpu(cpu)
	cpufreq_stats_free_table(cpu);
	return ret;
	}

	return 0;
	}
	static void __exit cpufreq_stats_exit(void)
	{
	unsigned int cpu;

	cpufreq_unregister_notifier(&notifier_policy_block,
	CPUFREQ_POLICY_NOTIFIER);
	cpufreq_unregister_notifier(&notifier_trans_block,
	CPUFREQ_TRANSITION_NOTIFIER);
	for_each_online_cpu(cpu)
	cpufreq_stats_free_table(cpu);
	}

	MODULE_AUTHOR("Zou Nan hai <nanhai.zou@intel.com>");
	MODULE_DESCRIPTION("Export cpufreq stats via sysfs");
	MODULE_LICENSE("GPL");

	module_init(cpufreq_stats_init);
	module_exit(cpufreq_stats_exit);