[mirror_ubuntu-bionic-kernel.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>

static DEFINE_SPINLOCK(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;
	unsigned int *trans_table;
};

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 void cpufreq_stats_clear_table(struct cpufreq_stats *stats)
{
	unsigned int count = stats->max_state;

	memset(stats->time_in_state, 0, count * sizeof(u64));
	memset(stats->trans_table, 0, count * count * sizeof(int));
	stats->last_time = get_jiffies_64();
	stats->total_trans = 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;

	if (policy->fast_switch_enabled)
		return 0;

	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;
}

static ssize_t store_reset(struct cpufreq_policy *policy, const char *buf,
			   size_t count)
{
	/* We don't care what is written to the attribute. */
	cpufreq_stats_clear_table(policy->stats);
	return count;
}

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;

	if (policy->fast_switch_enabled)
		return 0;

	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) {
		pr_warn_once("cpufreq transition table exceeds PAGE_SIZE. Disabling\n");
		return -EFBIG;
	}
	return len;
}
cpufreq_freq_attr_ro(trans_table);

cpufreq_freq_attr_ro(total_trans);
cpufreq_freq_attr_ro(time_in_state);
cpufreq_freq_attr_wo(reset);

static struct attribute *default_attrs[] = {
	&total_trans.attr,
	&time_in_state.attr,
	&reset.attr,
	&trans_table.attr,
	NULL
};
static const 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;
}

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;
}

void cpufreq_stats_create_table(struct cpufreq_policy *policy)
{
	unsigned int i = 0, count = 0, ret = -ENOMEM;
	struct cpufreq_stats *stats;
	unsigned int alloc_size;
	struct cpufreq_frequency_table *pos;

	count = cpufreq_table_count_valid_entries(policy);
	if (!count)
		return;

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

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

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

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

	/* 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);

	stats->trans_table = stats->freq_table + count;

	stats->max_state = count;

	/* Find valid-unique entries */
	cpufreq_for_each_valid_entry(pos, policy->freq_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;

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

void cpufreq_stats_record_transition(struct cpufreq_policy *policy,
				     unsigned int new_freq)
{
	struct cpufreq_stats *stats = policy->stats;
	int old_index, new_index;

	if (!stats) {
		pr_debug("%s: No stats found\n", __func__);
		return;
	}

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

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

	cpufreq_stats_update(stats);

	stats->last_index = new_index;
	stats->trans_table[old_index * stats->max_state + new_index]++;
	stats->total_trans++;
}
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>
1da177e4	16
1aefc75b	17	static DEFINE_SPINLOCK(cpufreq_stats_lock);
1da177e4	18
1da177e4	19	struct cpufreq_stats {
1da177e4	20	unsigned int total_trans;
bb176f7d	21	unsigned long long last_time;
1da177e4 LT	22	unsigned int max_state;
	23	unsigned int state_num;
	24	unsigned int last_index;
1e7586a1	25	u64 *time_in_state;
1da177e4	26	unsigned int *freq_table;
1da177e4	27	unsigned int *trans_table;
1da177e4 LT	28	};
1da177e4 LT	29
50941607	30	static int cpufreq_stats_update(struct cpufreq_stats *stats)
1da177e4	31	{
9531347c	32	unsigned long long cur_time = get_jiffies_64();
58f1df25	33
1da177e4	34	spin_lock(&cpufreq_stats_lock);
c960f9b2	35	stats->time_in_state[stats->last_index] += cur_time - stats->last_time;
50941607	36	stats->last_time = cur_time;
1da177e4 LT	37	spin_unlock(&cpufreq_stats_lock);
	38	return 0;
	39	}
	40
ee7930ee MM	41	static void cpufreq_stats_clear_table(struct cpufreq_stats *stats)
	42	{
	43	unsigned int count = stats->max_state;
	44
	45	memset(stats->time_in_state, 0, count * sizeof(u64));
ee7930ee	46	memset(stats->trans_table, 0, count * count * sizeof(int));
ee7930ee MM	47	stats->last_time = get_jiffies_64();
	48	stats->total_trans = 0;
	49	}
	50
0a829c5a	51	static ssize_t show_total_trans(struct cpufreq_policy policy, char buf)
1da177e4	52	{
a9aaf291	53	return sprintf(buf, "%d\n", policy->stats->total_trans);
1da177e4 LT	54	}
1da177e4 LT	55
0a829c5a	56	static ssize_t show_time_in_state(struct cpufreq_policy policy, char buf)
1da177e4	57	{
50941607	58	struct cpufreq_stats *stats = policy->stats;
1da177e4 LT	59	ssize_t len = 0;
1da177e4 LT	60	int i;
a9aaf291	61
1aefc75b RW	62	if (policy->fast_switch_enabled)
	63	return 0;
	64
50941607 VK	65	cpufreq_stats_update(stats);
	66	for (i = 0; i < stats->state_num; i++) {
	67	len += sprintf(buf + len, "%u %llu\n", stats->freq_table[i],
0a829c5a	68	(unsigned long long)
50941607	69	jiffies_64_to_clock_t(stats->time_in_state[i]));
1da177e4 LT	70	}
	71	return len;
	72	}
	73
ee7930ee MM	74	static ssize_t store_reset(struct cpufreq_policy policy, const char buf,
	75	size_t count)
	76	{
	77	/* We don't care what is written to the attribute. */
	78	cpufreq_stats_clear_table(policy->stats);
	79	return count;
	80	}
	81
0a829c5a	82	static ssize_t show_trans_table(struct cpufreq_policy policy, char buf)
1da177e4	83	{
50941607	84	struct cpufreq_stats *stats = policy->stats;
1da177e4 LT	85	ssize_t len = 0;
	86	int i, j;
	87
1aefc75b RW	88	if (policy->fast_switch_enabled)
	89	return 0;
	90
58f1df25 VP	91	len += snprintf(buf + len, PAGE_SIZE - len, " From : To\n");
58f1df25 VP	92	len += snprintf(buf + len, PAGE_SIZE - len, " : ");
50941607	93	for (i = 0; i < stats->state_num; i++) {
58f1df25 VP	94	if (len >= PAGE_SIZE)
	95	break;
	96	len += snprintf(buf + len, PAGE_SIZE - len, "%9u ",
50941607	97	stats->freq_table[i]);
58f1df25 VP	98	}
58f1df25 VP	99	if (len >= PAGE_SIZE)
25aca347	100	return PAGE_SIZE;
58f1df25 VP	101
	102	len += snprintf(buf + len, PAGE_SIZE - len, "\n");
	103
50941607	104	for (i = 0; i < stats->state_num; i++) {
1da177e4 LT	105	if (len >= PAGE_SIZE)
1da177e4 LT	106	break;
58f1df25 VP	107
58f1df25 VP	108	len += snprintf(buf + len, PAGE_SIZE - len, "%9u: ",
50941607	109	stats->freq_table[i]);
1da177e4	110
50941607	111	for (j = 0; j < stats->state_num; j++) {
1da177e4 LT	112	if (len >= PAGE_SIZE)
1da177e4 LT	113	break;
58f1df25	114	len += snprintf(buf + len, PAGE_SIZE - len, "%9u ",
50941607	115	stats->trans_table[i*stats->max_state+j]);
1da177e4	116	}
25aca347 CEB	117	if (len >= PAGE_SIZE)
25aca347 CEB	118	break;
1da177e4 LT	119	len += snprintf(buf + len, PAGE_SIZE - len, "\n");
1da177e4 LT	120	}
f7bc9b20 GS	121
	122	if (len >= PAGE_SIZE) {
	123	pr_warn_once("cpufreq transition table exceeds PAGE_SIZE. Disabling\n");
	124	return -EFBIG;
	125	}
1da177e4 LT	126	return len;
1da177e4 LT	127	}
df18e504	128	cpufreq_freq_attr_ro(trans_table);
1da177e4	129
df18e504 VK	130	cpufreq_freq_attr_ro(total_trans);
df18e504 VK	131	cpufreq_freq_attr_ro(time_in_state);
ee7930ee	132	cpufreq_freq_attr_wo(reset);
1da177e4 LT	133
1da177e4 LT	134	static struct attribute *default_attrs[] = {
df18e504 VK	135	&total_trans.attr,
df18e504 VK	136	&time_in_state.attr,
ee7930ee	137	&reset.attr,
df18e504	138	&trans_table.attr,
1da177e4 LT	139	NULL
1da177e4 LT	140	};
402202e8	141	static const struct attribute_group stats_attr_group = {
1da177e4 LT	142	.attrs = default_attrs,
	143	.name = "stats"
	144	};
	145
50941607	146	static int freq_table_get_index(struct cpufreq_stats *stats, unsigned int freq)
1da177e4 LT	147	{
1da177e4 LT	148	int index;
50941607 VK	149	for (index = 0; index < stats->max_state; index++)
50941607 VK	150	if (stats->freq_table[index] == freq)
1da177e4 LT	151	return index;
	152	return -1;
	153	}
	154
1aefc75b	155	void cpufreq_stats_free_table(struct cpufreq_policy *policy)
1da177e4	156	{
50941607	157	struct cpufreq_stats *stats = policy->stats;
b8eed8af	158
a9aaf291	159	/* Already freed */
50941607	160	if (!stats)
2d13594d VK	161	return;
2d13594d VK	162
50941607	163	pr_debug("%s: Free stats table\n", __func__);
2d13594d VK	164
2d13594d VK	165	sysfs_remove_group(&policy->kobj, &stats_attr_group);
50941607 VK	166	kfree(stats->time_in_state);
50941607 VK	167	kfree(stats);
a9aaf291	168	policy->stats = NULL;
98586ed8	169	}
98586ed8	170
1aefc75b	171	void cpufreq_stats_create_table(struct cpufreq_policy *policy)
1da177e4	172	{
a685c6d0	173	unsigned int i = 0, count = 0, ret = -ENOMEM;
50941607	174	struct cpufreq_stats *stats;
1da177e4	175	unsigned int alloc_size;
55d85293	176	struct cpufreq_frequency_table *pos;
ad4c2302	177
55d85293 VK	178	count = cpufreq_table_count_valid_entries(policy);
55d85293 VK	179	if (!count)
1aefc75b	180	return;
ad4c2302	181
b8c67448	182	/* stats already initialized */
a9aaf291	183	if (policy->stats)
1aefc75b	184	return;
b8c67448	185
50941607	186	stats = kzalloc(sizeof(*stats), GFP_KERNEL);
a685c6d0	187	if (!stats)
1aefc75b	188	return;
1da177e4	189
1e7586a1	190	alloc_size = count * sizeof(int) + count * sizeof(u64);
1da177e4	191
1da177e4	192	alloc_size += count * count * sizeof(int);
a685c6d0 VK	193
a685c6d0 VK	194	/* Allocate memory for time_in_state/freq_table/trans_table in one go */
50941607	195	stats->time_in_state = kzalloc(alloc_size, GFP_KERNEL);
a685c6d0 VK	196	if (!stats->time_in_state)
	197	goto free_stat;
	198
50941607	199	stats->freq_table = (unsigned int *)(stats->time_in_state + count);
1da177e4	200
50941607	201	stats->trans_table = stats->freq_table + count;
a685c6d0 VK	202
	203	stats->max_state = count;
	204
	205	/* Find valid-unique entries */
55d85293	206	cpufreq_for_each_valid_entry(pos, policy->freq_table)
50941607 VK	207	if (freq_table_get_index(stats, pos->frequency) == -1)
50941607 VK	208	stats->freq_table[i++] = pos->frequency;
a685c6d0	209
490285c6	210	stats->state_num = i;
50941607 VK	211	stats->last_time = get_jiffies_64();
50941607 VK	212	stats->last_index = freq_table_get_index(stats, policy->cur);
a685c6d0 VK	213
	214	policy->stats = stats;
	215	ret = sysfs_create_group(&policy->kobj, &stats_attr_group);
	216	if (!ret)
1aefc75b	217	return;
a685c6d0 VK	218
a685c6d0 VK	219	/* We failed, release resources */
a9aaf291	220	policy->stats = NULL;
a685c6d0 VK	221	kfree(stats->time_in_state);
	222	free_stat:
	223	kfree(stats);
b3f9ff88 VK	224	}
b3f9ff88 VK	225
1aefc75b RW	226	void cpufreq_stats_record_transition(struct cpufreq_policy *policy,
1aefc75b RW	227	unsigned int new_freq)
1da177e4	228	{
1aefc75b	229	struct cpufreq_stats *stats = policy->stats;
1da177e4 LT	230	int old_index, new_index;
1da177e4 LT	231
1aefc75b	232	if (!stats) {
a9aaf291	233	pr_debug("%s: No stats found\n", __func__);
1aefc75b	234	return;
a9aaf291 VK	235	}
a9aaf291 VK	236
50941607	237	old_index = stats->last_index;
1aefc75b	238	new_index = freq_table_get_index(stats, new_freq);
1da177e4	239
50941607	240	/* We can't do stats->time_in_state[-1]= .. */
1aefc75b RW	241	if (old_index == -1 \|\| new_index == -1 \|\| old_index == new_index)
1aefc75b RW	242	return;
8edc59d9	243
e7347694 VK	244	cpufreq_stats_update(stats);
e7347694 VK	245
50941607	246	stats->last_index = new_index;
50941607	247	stats->trans_table[old_index * stats->max_state + new_index]++;
50941607	248	stats->total_trans++;
1da177e4	249	}