[deliverable/linux.git] / drivers / cpufreq / cpufreq_stats.c

/*
 *  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 cpu;
	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 *stat)
{
	unsigned long long cur_time = get_jiffies_64();

	spin_lock(&cpufreq_stats_lock);
	if (stat->time_in_state)
		stat->time_in_state[stat->last_index] +=
			cur_time - stat->last_time;
	stat->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 *stat = policy->stats;
	ssize_t len = 0;
	int i;

	cpufreq_stats_update(stat);
	for (i = 0; i < stat->state_num; i++) {
		len += sprintf(buf + len, "%u %llu\n", stat->freq_table[i],
			(unsigned long long)
			jiffies_64_to_clock_t(stat->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 *stat = policy->stats;
	ssize_t len = 0;
	int i, j;

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

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

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

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

		for (j = 0; j < stat->state_num; j++) {
			if (len >= PAGE_SIZE)
				break;
			len += snprintf(buf + len, PAGE_SIZE - len, "%9u ",
					stat->trans_table[i*stat->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 *stat, unsigned int freq)
{
	int index;
	for (index = 0; index < stat->max_state; index++)
		if (stat->freq_table[index] == freq)
			return index;
	return -1;
}

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

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

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

	sysfs_remove_group(&policy->kobj, &stats_attr_group);
	kfree(stat->time_in_state);
	kfree(stat);
	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, count = 0, ret = 0;
	struct cpufreq_stats *stat;
	unsigned int alloc_size;
	unsigned int cpu = policy->cpu;
	struct cpufreq_frequency_table *pos, *table;

	table = cpufreq_frequency_get_table(cpu);
	if (unlikely(!table))
		return 0;

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

	stat = kzalloc(sizeof(*stat), GFP_KERNEL);
	if ((stat) == NULL)
		return -ENOMEM;

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

	stat->cpu = cpu;
	policy->stats = stat;

	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
	stat->max_state = count;
	stat->time_in_state = kzalloc(alloc_size, GFP_KERNEL);
	if (!stat->time_in_state) {
		ret = -ENOMEM;
		goto error_alloc;
	}
	stat->freq_table = (unsigned int *)(stat->time_in_state + count);

#ifdef CONFIG_CPU_FREQ_STAT_DETAILS
	stat->trans_table = stat->freq_table + count;
#endif
	i = 0;
	cpufreq_for_each_valid_entry(pos, table)
		if (freq_table_get_index(stat, pos->frequency) == -1)
			stat->freq_table[i++] = pos->frequency;
	stat->state_num = i;
	spin_lock(&cpufreq_stats_lock);
	stat->last_time = get_jiffies_64();
	stat->last_index = freq_table_get_index(stat, policy->cur);
	spin_unlock(&cpufreq_stats_lock);
	return 0;
error_alloc:
	sysfs_remove_group(&policy->kobj, &stats_attr_group);
error_out:
	kfree(stat);
	policy->stats = NULL;
	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 void cpufreq_stats_update_policy_cpu(struct cpufreq_policy *policy)
{
	policy->stats->cpu = policy->cpu;
}

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_UPDATE_POLICY_CPU) {
		cpufreq_stats_update_policy_cpu(policy);
		return 0;
	}

	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 *stat;
	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;
	}

	stat = policy->stats;

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

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

	cpufreq_stats_update(stat);

	if (old_index == new_index)
		goto put_policy;

	spin_lock(&cpufreq_stats_lock);
	stat->last_index = new_index;
#ifdef CONFIG_CPU_FREQ_STAT_DETAILS
	stat->trans_table[old_index * stat->max_state + new_index]++;
#endif
	stat->total_trans++;
	spin_unlock(&cpufreq_stats_lock);

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);
Commit	Line	Data
1da177e4 LT	1	/*
	2	* drivers/cpufreq/cpufreq_stats.c
	3	*
	4	* Copyright (C) 2003-2004 Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>.
0a829c5a	5	* (C) 2004 Zou Nan hai <nanhai.zou@intel.com>.
1da177e4 LT	6	*
	7	* This program is free software; you can redistribute it and/or modify
	8	* it under the terms of the GNU General Public License version 2 as
	9	* published by the Free Software Foundation.
	10	*/
	11
1da177e4	12	#include <linux/cpu.h>
1da177e4	13	#include <linux/cpufreq.h>
5c720d37	14	#include <linux/module.h>
5ff0a268	15	#include <linux/slab.h>
bfc3f028	16	#include <linux/cputime.h>
1da177e4 LT	17
	18	static spinlock_t cpufreq_stats_lock;
	19
1da177e4 LT	20	struct cpufreq_stats {
	21	unsigned int cpu;
	22	unsigned int total_trans;
bb176f7d	23	unsigned long long last_time;
1da177e4 LT	24	unsigned int max_state;
	25	unsigned int state_num;
	26	unsigned int last_index;
1e7586a1	27	u64 *time_in_state;
1da177e4 LT	28	unsigned int *freq_table;
	29	#ifdef CONFIG_CPU_FREQ_STAT_DETAILS
	30	unsigned int *trans_table;
	31	#endif
	32	};
	33
2aba0c1b	34	static int cpufreq_stats_update(struct cpufreq_stats *stat)
1da177e4	35	{
9531347c	36	unsigned long long cur_time = get_jiffies_64();
58f1df25	37
1da177e4	38	spin_lock(&cpufreq_stats_lock);
1da177e4	39	if (stat->time_in_state)
64861634 MS	40	stat->time_in_state[stat->last_index] +=
64861634 MS	41	cur_time - stat->last_time;
58f1df25	42	stat->last_time = cur_time;
1da177e4 LT	43	spin_unlock(&cpufreq_stats_lock);
	44	return 0;
	45	}
	46
0a829c5a	47	static ssize_t show_total_trans(struct cpufreq_policy policy, char buf)
1da177e4	48	{
a9aaf291	49	return sprintf(buf, "%d\n", policy->stats->total_trans);
1da177e4 LT	50	}
1da177e4 LT	51
0a829c5a	52	static ssize_t show_time_in_state(struct cpufreq_policy policy, char buf)
1da177e4	53	{
a9aaf291	54	struct cpufreq_stats *stat = policy->stats;
1da177e4 LT	55	ssize_t len = 0;
1da177e4 LT	56	int i;
a9aaf291	57
2aba0c1b	58	cpufreq_stats_update(stat);
1da177e4	59	for (i = 0; i < stat->state_num; i++) {
32ee8c3e	60	len += sprintf(buf + len, "%u %llu\n", stat->freq_table[i],
0a829c5a	61	(unsigned long long)
a857c0b9	62	jiffies_64_to_clock_t(stat->time_in_state[i]));
1da177e4 LT	63	}
	64	return len;
	65	}
	66
	67	#ifdef CONFIG_CPU_FREQ_STAT_DETAILS
0a829c5a	68	static ssize_t show_trans_table(struct cpufreq_policy policy, char buf)
1da177e4	69	{
a9aaf291	70	struct cpufreq_stats *stat = policy->stats;
1da177e4 LT	71	ssize_t len = 0;
	72	int i, j;
	73
2aba0c1b	74	cpufreq_stats_update(stat);
58f1df25 VP	75	len += snprintf(buf + len, PAGE_SIZE - len, " From : To\n");
	76	len += snprintf(buf + len, PAGE_SIZE - len, " : ");
	77	for (i = 0; i < stat->state_num; i++) {
	78	if (len >= PAGE_SIZE)
	79	break;
	80	len += snprintf(buf + len, PAGE_SIZE - len, "%9u ",
	81	stat->freq_table[i]);
	82	}
	83	if (len >= PAGE_SIZE)
25aca347	84	return PAGE_SIZE;
58f1df25 VP	85
	86	len += snprintf(buf + len, PAGE_SIZE - len, "\n");
	87
1da177e4 LT	88	for (i = 0; i < stat->state_num; i++) {
	89	if (len >= PAGE_SIZE)
	90	break;
58f1df25 VP	91
58f1df25 VP	92	len += snprintf(buf + len, PAGE_SIZE - len, "%9u: ",
1da177e4 LT	93	stat->freq_table[i]);
1da177e4 LT	94
bb176f7d	95	for (j = 0; j < stat->state_num; j++) {
1da177e4 LT	96	if (len >= PAGE_SIZE)
1da177e4 LT	97	break;
58f1df25	98	len += snprintf(buf + len, PAGE_SIZE - len, "%9u ",
1da177e4 LT	99	stat->trans_table[i*stat->max_state+j]);
1da177e4 LT	100	}
25aca347 CEB	101	if (len >= PAGE_SIZE)
25aca347 CEB	102	break;
1da177e4 LT	103	len += snprintf(buf + len, PAGE_SIZE - len, "\n");
1da177e4 LT	104	}
25aca347 CEB	105	if (len >= PAGE_SIZE)
25aca347 CEB	106	return PAGE_SIZE;
1da177e4 LT	107	return len;
1da177e4 LT	108	}
df18e504	109	cpufreq_freq_attr_ro(trans_table);
1da177e4 LT	110	#endif
1da177e4 LT	111
df18e504 VK	112	cpufreq_freq_attr_ro(total_trans);
df18e504 VK	113	cpufreq_freq_attr_ro(time_in_state);
1da177e4 LT	114
1da177e4 LT	115	static struct attribute *default_attrs[] = {
df18e504 VK	116	&total_trans.attr,
df18e504 VK	117	&time_in_state.attr,
1da177e4	118	#ifdef CONFIG_CPU_FREQ_STAT_DETAILS
df18e504	119	&trans_table.attr,
1da177e4 LT	120	#endif
	121	NULL
	122	};
	123	static struct attribute_group stats_attr_group = {
	124	.attrs = default_attrs,
	125	.name = "stats"
	126	};
	127
0a829c5a	128	static int freq_table_get_index(struct cpufreq_stats *stat, unsigned int freq)
1da177e4 LT	129	{
	130	int index;
	131	for (index = 0; index < stat->max_state; index++)
	132	if (stat->freq_table[index] == freq)
	133	return index;
	134	return -1;
	135	}
	136
2d13594d	137	static void __cpufreq_stats_free_table(struct cpufreq_policy *policy)
1da177e4	138	{
a9aaf291	139	struct cpufreq_stats *stat = policy->stats;
b8eed8af	140
a9aaf291	141	/* Already freed */
2d13594d VK	142	if (!stat)
	143	return;
	144
	145	pr_debug("%s: Free stat table\n", __func__);
	146
	147	sysfs_remove_group(&policy->kobj, &stats_attr_group);
	148	kfree(stat->time_in_state);
	149	kfree(stat);
a9aaf291	150	policy->stats = NULL;
98586ed8	151	}
98586ed8	152
2d13594d	153	static void cpufreq_stats_free_table(unsigned int cpu)
98586ed8	154	{
2d13594d	155	struct cpufreq_policy *policy;
633d47d6	156
2d13594d	157	policy = cpufreq_cpu_get(cpu);
187da1d9	158	if (!policy)
633d47d6 DB	159	return;
633d47d6 DB	160
f93dbbbd	161	__cpufreq_stats_free_table(policy);
187da1d9	162
187da1d9	163	cpufreq_cpu_put(policy);
1da177e4 LT	164	}
1da177e4 LT	165
ad4c2302	166	static int __cpufreq_stats_create_table(struct cpufreq_policy *policy)
1da177e4	167	{
041526f9	168	unsigned int i, count = 0, ret = 0;
1da177e4	169	struct cpufreq_stats *stat;
1da177e4 LT	170	unsigned int alloc_size;
1da177e4 LT	171	unsigned int cpu = policy->cpu;
041526f9	172	struct cpufreq_frequency_table pos, table;
ad4c2302 SK	173
	174	table = cpufreq_frequency_get_table(cpu);
	175	if (unlikely(!table))
	176	return 0;
	177
b8c67448	178	/* stats already initialized */
a9aaf291	179	if (policy->stats)
b8c67448 VK	180	return -EEXIST;
b8c67448 VK	181
d5b73cd8	182	stat = kzalloc(sizeof(*stat), GFP_KERNEL);
0a829c5a	183	if ((stat) == NULL)
1da177e4	184	return -ENOMEM;
1da177e4	185
b24a5b65	186	ret = sysfs_create_group(&policy->kobj, &stats_attr_group);
0a829c5a	187	if (ret)
1da177e4 LT	188	goto error_out;
	189
	190	stat->cpu = cpu;
a9aaf291	191	policy->stats = stat;
1da177e4	192
041526f9	193	cpufreq_for_each_valid_entry(pos, table)
1da177e4	194	count++;
1da177e4	195
1e7586a1	196	alloc_size = count * sizeof(int) + count * sizeof(u64);
1da177e4 LT	197
	198	#ifdef CONFIG_CPU_FREQ_STAT_DETAILS
	199	alloc_size += count * count * sizeof(int);
	200	#endif
	201	stat->max_state = count;
e98df50c	202	stat->time_in_state = kzalloc(alloc_size, GFP_KERNEL);
1da177e4 LT	203	if (!stat->time_in_state) {
1da177e4 LT	204	ret = -ENOMEM;
0b7528d9	205	goto error_alloc;
1da177e4	206	}
1da177e4 LT	207	stat->freq_table = (unsigned int *)(stat->time_in_state + count);
	208
	209	#ifdef CONFIG_CPU_FREQ_STAT_DETAILS
	210	stat->trans_table = stat->freq_table + count;
	211	#endif
041526f9 SK	212	i = 0;
	213	cpufreq_for_each_valid_entry(pos, table)
	214	if (freq_table_get_index(stat, pos->frequency) == -1)
	215	stat->freq_table[i++] = pos->frequency;
	216	stat->state_num = i;
1da177e4	217	spin_lock(&cpufreq_stats_lock);
58f1df25	218	stat->last_time = get_jiffies_64();
1da177e4 LT	219	stat->last_index = freq_table_get_index(stat, policy->cur);
1da177e4 LT	220	spin_unlock(&cpufreq_stats_lock);
1da177e4	221	return 0;
0b7528d9 SK	222	error_alloc:
0b7528d9 SK	223	sysfs_remove_group(&policy->kobj, &stats_attr_group);
1da177e4	224	error_out:
1da177e4	225	kfree(stat);
a9aaf291	226	policy->stats = NULL;
1da177e4 LT	227	return ret;
	228	}
	229
b3f9ff88 VK	230	static void cpufreq_stats_create_table(unsigned int cpu)
	231	{
	232	struct cpufreq_policy *policy;
b3f9ff88 VK	233
	234	/*
	235	* "likely(!policy)" because normally cpufreq_stats will be registered
	236	* before cpufreq driver
	237	*/
	238	policy = cpufreq_cpu_get(cpu);
	239	if (likely(!policy))
	240	return;
	241
ad4c2302	242	__cpufreq_stats_create_table(policy);
b3f9ff88 VK	243
	244	cpufreq_cpu_put(policy);
	245	}
	246
b8eed8af VK	247	static void cpufreq_stats_update_policy_cpu(struct cpufreq_policy *policy)
b8eed8af VK	248	{
a9aaf291	249	policy->stats->cpu = policy->cpu;
b8eed8af VK	250	}
b8eed8af VK	251
0a829c5a DJ	252	static int cpufreq_stat_notifier_policy(struct notifier_block *nb,
0a829c5a DJ	253	unsigned long val, void *data)
1da177e4	254	{
fcd7af91	255	int ret = 0;
1da177e4	256	struct cpufreq_policy *policy = data;
b8eed8af VK	257
	258	if (val == CPUFREQ_UPDATE_POLICY_CPU) {
	259	cpufreq_stats_update_policy_cpu(policy);
	260	return 0;
	261	}
	262
fcd7af91	263	if (val == CPUFREQ_CREATE_POLICY)
ad4c2302	264	ret = __cpufreq_stats_create_table(policy);
2d13594d VK	265	else if (val == CPUFREQ_REMOVE_POLICY)
2d13594d VK	266	__cpufreq_stats_free_table(policy);
fcd7af91 VK	267
fcd7af91 VK	268	return ret;
1da177e4 LT	269	}
1da177e4 LT	270
0a829c5a DJ	271	static int cpufreq_stat_notifier_trans(struct notifier_block *nb,
0a829c5a DJ	272	unsigned long val, void *data)
1da177e4 LT	273	{
1da177e4 LT	274	struct cpufreq_freqs *freq = data;
a9aaf291	275	struct cpufreq_policy *policy = cpufreq_cpu_get(freq->cpu);
1da177e4 LT	276	struct cpufreq_stats *stat;
	277	int old_index, new_index;
	278
a9aaf291 VK	279	if (!policy) {
a9aaf291 VK	280	pr_err("%s: No policy found\n", __func__);
1da177e4	281	return 0;
a9aaf291	282	}
1da177e4	283
a9aaf291 VK	284	if (val != CPUFREQ_POSTCHANGE)
	285	goto put_policy;
	286
	287	if (!policy->stats) {
	288	pr_debug("%s: No stats found\n", __func__);
	289	goto put_policy;
	290	}
	291
	292	stat = policy->stats;
8edc59d9	293
6501faf8	294	old_index = stat->last_index;
1da177e4 LT	295	new_index = freq_table_get_index(stat, freq->new);
1da177e4 LT	296
46a310b8 KRW	297	/* We can't do stat->time_in_state[-1]= .. */
46a310b8 KRW	298	if (old_index == -1 \|\| new_index == -1)
a9aaf291	299	goto put_policy;
1da177e4	300
2aba0c1b	301	cpufreq_stats_update(stat);
46a310b8 KRW	302
46a310b8 KRW	303	if (old_index == new_index)
a9aaf291	304	goto put_policy;
8edc59d9	305
1da177e4 LT	306	spin_lock(&cpufreq_stats_lock);
	307	stat->last_index = new_index;
	308	#ifdef CONFIG_CPU_FREQ_STAT_DETAILS
	309	stat->trans_table[old_index * stat->max_state + new_index]++;
	310	#endif
	311	stat->total_trans++;
	312	spin_unlock(&cpufreq_stats_lock);
a9aaf291 VK	313
	314	put_policy:
	315	cpufreq_cpu_put(policy);
1da177e4 LT	316	return 0;
	317	}
	318
	319	static struct notifier_block notifier_policy_block = {
	320	.notifier_call = cpufreq_stat_notifier_policy
	321	};
	322
	323	static struct notifier_block notifier_trans_block = {
	324	.notifier_call = cpufreq_stat_notifier_trans
	325	};
	326
0a829c5a	327	static int __init cpufreq_stats_init(void)
1da177e4 LT	328	{
	329	int ret;
	330	unsigned int cpu;
c32b6b8e	331
1da177e4	332	spin_lock_init(&cpufreq_stats_lock);
0a829c5a DJ	333	ret = cpufreq_register_notifier(&notifier_policy_block,
	334	CPUFREQ_POLICY_NOTIFIER);
	335	if (ret)
1da177e4 LT	336	return ret;
1da177e4 LT	337
b3f9ff88 VK	338	for_each_online_cpu(cpu)
	339	cpufreq_stats_create_table(cpu);
	340
0a829c5a DJ	341	ret = cpufreq_register_notifier(&notifier_trans_block,
	342	CPUFREQ_TRANSITION_NOTIFIER);
	343	if (ret) {
1da177e4 LT	344	cpufreq_unregister_notifier(&notifier_policy_block,
1da177e4 LT	345	CPUFREQ_POLICY_NOTIFIER);
56836fb4 KK	346	for_each_online_cpu(cpu)
56836fb4 KK	347	cpufreq_stats_free_table(cpu);
1da177e4 LT	348	return ret;
	349	}
	350
1da177e4 LT	351	return 0;
1da177e4 LT	352	}
0a829c5a	353	static void __exit cpufreq_stats_exit(void)
1da177e4 LT	354	{
1da177e4 LT	355	unsigned int cpu;
c32b6b8e	356
1da177e4 LT	357	cpufreq_unregister_notifier(&notifier_policy_block,
	358	CPUFREQ_POLICY_NOTIFIER);
	359	cpufreq_unregister_notifier(&notifier_trans_block,
	360	CPUFREQ_TRANSITION_NOTIFIER);
2d13594d	361	for_each_online_cpu(cpu)
55395ae7	362	cpufreq_stats_free_table(cpu);
1da177e4 LT	363	}
1da177e4 LT	364
0a829c5a	365	MODULE_AUTHOR("Zou Nan hai <nanhai.zou@intel.com>");
00d0b294	366	MODULE_DESCRIPTION("Export cpufreq stats via sysfs");
0a829c5a	367	MODULE_LICENSE("GPL");
1da177e4 LT	368
	369	module_init(cpufreq_stats_init);
	370	module_exit(cpufreq_stats_exit);