2 * drivers/cpufreq/cpufreq_stats.c
4 * Copyright (C) 2003-2004 Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>.
5 * (C) 2004 Zou Nan hai <nanhai.zou@intel.com>.
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.
12 #include <linux/kernel.h>
13 #include <linux/slab.h>
14 #include <linux/cpu.h>
15 #include <linux/sysfs.h>
16 #include <linux/cpufreq.h>
17 #include <linux/module.h>
18 #include <linux/jiffies.h>
19 #include <linux/percpu.h>
20 #include <linux/kobject.h>
21 #include <linux/spinlock.h>
22 #include <linux/notifier.h>
23 #include <linux/sort.h>
24 #include <linux/err.h>
26 #include <linux/sched.h>
27 #include <asm/cputime.h>
28 #ifdef CONFIG_BL_SWITCHER
29 #include <asm/bL_switcher.h>
32 static spinlock_t cpufreq_stats_lock;
34 struct cpufreq_stats {
36 unsigned int total_trans;
37 unsigned long long last_time;
38 unsigned int max_state;
39 unsigned int state_num;
40 unsigned int last_index;
42 unsigned int *freq_table;
43 #ifdef CONFIG_CPU_FREQ_STAT_DETAILS
44 unsigned int *trans_table;
48 struct all_cpufreq_stats {
49 unsigned int state_num;
50 cputime64_t *time_in_state;
51 unsigned int *freq_table;
54 struct cpufreq_power_stats {
55 unsigned int state_num;
57 unsigned int *freq_table;
60 struct all_freq_table {
61 unsigned int *freq_table;
62 unsigned int table_size;
65 static struct all_freq_table *all_freq_table;
67 static DEFINE_PER_CPU(struct all_cpufreq_stats *, all_cpufreq_stats);
68 static DEFINE_PER_CPU(struct cpufreq_stats *, cpufreq_stats_table);
69 static DEFINE_PER_CPU(struct cpufreq_power_stats *, cpufreq_power_stats);
71 struct cpufreq_stats_attribute {
72 struct attribute attr;
73 ssize_t(*show) (struct cpufreq_stats *, char *);
76 static int cpufreq_stats_update(unsigned int cpu)
78 struct cpufreq_stats *stat;
79 struct all_cpufreq_stats *all_stat;
80 unsigned long long cur_time;
82 cur_time = get_jiffies_64();
83 spin_lock(&cpufreq_stats_lock);
84 stat = per_cpu(cpufreq_stats_table, cpu);
85 all_stat = per_cpu(all_cpufreq_stats, cpu);
87 spin_unlock(&cpufreq_stats_lock);
90 if (stat->time_in_state) {
91 stat->time_in_state[stat->last_index] +=
92 cur_time - stat->last_time;
94 all_stat->time_in_state[stat->last_index] +=
95 cur_time - stat->last_time;
97 stat->last_time = cur_time;
98 spin_unlock(&cpufreq_stats_lock);
102 static ssize_t show_total_trans(struct cpufreq_policy *policy, char *buf)
104 struct cpufreq_stats *stat = per_cpu(cpufreq_stats_table, policy->cpu);
107 return sprintf(buf, "%d\n",
108 per_cpu(cpufreq_stats_table, stat->cpu)->total_trans);
111 static ssize_t show_time_in_state(struct cpufreq_policy *policy, char *buf)
115 struct cpufreq_stats *stat = per_cpu(cpufreq_stats_table, policy->cpu);
118 cpufreq_stats_update(stat->cpu);
119 for (i = 0; i < stat->state_num; i++) {
120 len += sprintf(buf + len, "%u %llu\n", stat->freq_table[i],
122 jiffies_64_to_clock_t(stat->time_in_state[i]));
127 static int get_index_all_cpufreq_stat(struct all_cpufreq_stats *all_stat,
133 for (i = 0; i < all_stat->state_num; i++) {
134 if (all_stat->freq_table[i] == freq)
140 void acct_update_power(struct task_struct *task, cputime_t cputime) {
141 struct cpufreq_power_stats *powerstats;
142 struct cpufreq_stats *stats;
143 unsigned int cpu_num, curr;
147 cpu_num = task_cpu(task);
148 powerstats = per_cpu(cpufreq_power_stats, cpu_num);
149 stats = per_cpu(cpufreq_stats_table, cpu_num);
150 if (!powerstats || !stats)
153 curr = powerstats->curr[stats->last_index];
154 if (task->cpu_power != ULLONG_MAX)
155 task->cpu_power += curr * cputime_to_usecs(cputime);
157 EXPORT_SYMBOL_GPL(acct_update_power);
159 static ssize_t show_current_in_state(struct kobject *kobj,
160 struct kobj_attribute *attr, char *buf)
164 struct cpufreq_power_stats *powerstats;
166 spin_lock(&cpufreq_stats_lock);
167 for_each_possible_cpu(cpu) {
168 powerstats = per_cpu(cpufreq_power_stats, cpu);
171 len += scnprintf(buf + len, PAGE_SIZE - len, "CPU%d:", cpu);
172 for (i = 0; i < powerstats->state_num; i++)
173 len += scnprintf(buf + len, PAGE_SIZE - len,
174 "%d=%d ", powerstats->freq_table[i],
175 powerstats->curr[i]);
176 len += scnprintf(buf + len, PAGE_SIZE - len, "\n");
178 spin_unlock(&cpufreq_stats_lock);
182 static ssize_t show_all_time_in_state(struct kobject *kobj,
183 struct kobj_attribute *attr, char *buf)
186 unsigned int i, cpu, freq, index;
187 struct all_cpufreq_stats *all_stat;
188 struct cpufreq_policy *policy;
190 len += scnprintf(buf + len, PAGE_SIZE - len, "freq\t\t");
191 for_each_possible_cpu(cpu) {
192 len += scnprintf(buf + len, PAGE_SIZE - len, "cpu%d\t\t", cpu);
194 cpufreq_stats_update(cpu);
199 for (i = 0; i < all_freq_table->table_size; i++) {
200 freq = all_freq_table->freq_table[i];
201 len += scnprintf(buf + len, PAGE_SIZE - len, "\n%u\t\t", freq);
202 for_each_possible_cpu(cpu) {
203 policy = cpufreq_cpu_get(cpu);
206 all_stat = per_cpu(all_cpufreq_stats, policy->cpu);
207 index = get_index_all_cpufreq_stat(all_stat, freq);
209 len += scnprintf(buf + len, PAGE_SIZE - len,
210 "%llu\t\t", (unsigned long long)
211 cputime64_to_clock_t(all_stat->time_in_state[index]));
213 len += scnprintf(buf + len, PAGE_SIZE - len,
216 cpufreq_cpu_put(policy);
221 len += scnprintf(buf + len, PAGE_SIZE - len, "\n");
225 #ifdef CONFIG_CPU_FREQ_STAT_DETAILS
226 static ssize_t show_trans_table(struct cpufreq_policy *policy, char *buf)
231 struct cpufreq_stats *stat = per_cpu(cpufreq_stats_table, policy->cpu);
234 cpufreq_stats_update(stat->cpu);
235 len += snprintf(buf + len, PAGE_SIZE - len, " From : To\n");
236 len += snprintf(buf + len, PAGE_SIZE - len, " : ");
237 for (i = 0; i < stat->state_num; i++) {
238 if (len >= PAGE_SIZE)
240 len += snprintf(buf + len, PAGE_SIZE - len, "%9u ",
241 stat->freq_table[i]);
243 if (len >= PAGE_SIZE)
246 len += snprintf(buf + len, PAGE_SIZE - len, "\n");
248 for (i = 0; i < stat->state_num; i++) {
249 if (len >= PAGE_SIZE)
252 len += snprintf(buf + len, PAGE_SIZE - len, "%9u: ",
253 stat->freq_table[i]);
255 for (j = 0; j < stat->state_num; j++) {
256 if (len >= PAGE_SIZE)
258 len += snprintf(buf + len, PAGE_SIZE - len, "%9u ",
259 stat->trans_table[i*stat->max_state+j]);
261 if (len >= PAGE_SIZE)
263 len += snprintf(buf + len, PAGE_SIZE - len, "\n");
265 if (len >= PAGE_SIZE)
269 cpufreq_freq_attr_ro(trans_table);
272 cpufreq_freq_attr_ro(total_trans);
273 cpufreq_freq_attr_ro(time_in_state);
275 static struct attribute *default_attrs[] = {
278 #ifdef CONFIG_CPU_FREQ_STAT_DETAILS
283 static struct attribute_group stats_attr_group = {
284 .attrs = default_attrs,
288 static struct kobj_attribute _attr_all_time_in_state = __ATTR(all_time_in_state,
289 0444, show_all_time_in_state, NULL);
291 static struct kobj_attribute _attr_current_in_state = __ATTR(current_in_state,
292 0444, show_current_in_state, NULL);
294 static int freq_table_get_index(struct cpufreq_stats *stat, unsigned int freq)
297 for (index = 0; index < stat->max_state; index++)
298 if (stat->freq_table[index] == freq)
303 /* should be called late in the CPU removal sequence so that the stats
304 * memory is still available in case someone tries to use it.
306 static void cpufreq_stats_free_table(unsigned int cpu)
308 struct cpufreq_stats *stat = per_cpu(cpufreq_stats_table, cpu);
311 pr_debug("%s: Free stat table\n", __func__);
312 kfree(stat->time_in_state);
314 per_cpu(cpufreq_stats_table, cpu) = NULL;
318 /* must be called early in the CPU removal sequence (before
319 * cpufreq_remove_dev) so that policy is still valid.
321 static void cpufreq_stats_free_sysfs(unsigned int cpu)
323 struct cpufreq_policy *policy = cpufreq_cpu_get(cpu);
328 if (!cpufreq_frequency_get_table(cpu))
331 if (!policy_is_shared(policy)) {
332 pr_debug("%s: Free sysfs stat\n", __func__);
333 sysfs_remove_group(&policy->kobj, &stats_attr_group);
337 cpufreq_cpu_put(policy);
340 static void cpufreq_allstats_free(void)
343 struct all_cpufreq_stats *all_stat;
345 sysfs_remove_file(cpufreq_global_kobject,
346 &_attr_all_time_in_state.attr);
348 for_each_possible_cpu(cpu) {
349 all_stat = per_cpu(all_cpufreq_stats, cpu);
352 kfree(all_stat->time_in_state);
354 per_cpu(all_cpufreq_stats, cpu) = NULL;
356 if (all_freq_table) {
357 kfree(all_freq_table->freq_table);
358 kfree(all_freq_table);
359 all_freq_table = NULL;
363 static void cpufreq_powerstats_free(void)
366 struct cpufreq_power_stats *powerstats;
368 sysfs_remove_file(cpufreq_global_kobject, &_attr_current_in_state.attr);
370 for_each_possible_cpu(cpu) {
371 powerstats = per_cpu(cpufreq_power_stats, cpu);
374 kfree(powerstats->curr);
376 per_cpu(cpufreq_power_stats, cpu) = NULL;
380 static int cpufreq_stats_create_table(struct cpufreq_policy *policy,
381 struct cpufreq_frequency_table *table, int count)
383 unsigned int i, j, ret = 0;
384 struct cpufreq_stats *stat;
385 struct cpufreq_policy *data;
386 unsigned int alloc_size;
387 unsigned int cpu = policy->cpu;
388 if (per_cpu(cpufreq_stats_table, cpu))
390 stat = kzalloc(sizeof(struct cpufreq_stats), GFP_KERNEL);
394 data = cpufreq_cpu_get(cpu);
400 ret = sysfs_create_group(&data->kobj, &stats_attr_group);
405 per_cpu(cpufreq_stats_table, cpu) = stat;
408 alloc_size = count * sizeof(int) + count * sizeof(u64);
410 #ifdef CONFIG_CPU_FREQ_STAT_DETAILS
411 alloc_size += count * count * sizeof(int);
413 stat->max_state = count;
414 stat->time_in_state = kzalloc(alloc_size, GFP_KERNEL);
415 if (!stat->time_in_state) {
419 stat->freq_table = (unsigned int *)(stat->time_in_state + count);
421 #ifdef CONFIG_CPU_FREQ_STAT_DETAILS
422 stat->trans_table = stat->freq_table + count;
425 for (i = 0; table[i].frequency != CPUFREQ_TABLE_END; i++) {
426 unsigned int freq = table[i].frequency;
427 if (freq == CPUFREQ_ENTRY_INVALID)
429 if (freq_table_get_index(stat, freq) == -1)
430 stat->freq_table[j++] = freq;
433 spin_lock(&cpufreq_stats_lock);
434 stat->last_time = get_jiffies_64();
435 stat->last_index = freq_table_get_index(stat, policy->cur);
436 #ifdef CONFIG_ARCH_ROCKCHIP
437 if (stat->last_index == -1)
438 stat->last_index = 0;
440 spin_unlock(&cpufreq_stats_lock);
441 cpufreq_cpu_put(data);
444 cpufreq_cpu_put(data);
447 per_cpu(cpufreq_stats_table, cpu) = NULL;
451 static void cpufreq_stats_update_policy_cpu(struct cpufreq_policy *policy)
453 struct cpufreq_stats *stat = per_cpu(cpufreq_stats_table,
456 pr_debug("Updating stats_table for new_cpu %u from last_cpu %u\n",
457 policy->cpu, policy->last_cpu);
458 per_cpu(cpufreq_stats_table, policy->cpu) = per_cpu(cpufreq_stats_table,
460 per_cpu(cpufreq_stats_table, policy->last_cpu) = NULL;
461 stat->cpu = policy->cpu;
464 static void cpufreq_powerstats_create(unsigned int cpu,
465 struct cpufreq_frequency_table *table, int count) {
466 unsigned int alloc_size, i = 0, j = 0, ret = 0;
467 struct cpufreq_power_stats *powerstats;
468 struct device_node *cpu_node;
469 char device_path[16];
471 powerstats = kzalloc(sizeof(struct cpufreq_power_stats),
476 /* Allocate memory for freq table per cpu as well as clockticks per
478 alloc_size = count * sizeof(unsigned int) +
479 count * sizeof(unsigned int);
480 powerstats->curr = kzalloc(alloc_size, GFP_KERNEL);
481 if (!powerstats->curr) {
485 powerstats->freq_table = powerstats->curr + count;
487 spin_lock(&cpufreq_stats_lock);
488 for (i = 0; table[i].frequency != CPUFREQ_TABLE_END && j < count; i++) {
489 unsigned int freq = table[i].frequency;
491 if (freq == CPUFREQ_ENTRY_INVALID)
493 powerstats->freq_table[j++] = freq;
495 powerstats->state_num = j;
497 snprintf(device_path, sizeof(device_path), "/cpus/cpu@%d", cpu);
498 cpu_node = of_find_node_by_path(device_path);
500 ret = of_property_read_u32_array(cpu_node, "current",
501 powerstats->curr, count);
503 kfree(powerstats->curr);
508 per_cpu(cpufreq_power_stats, cpu) = powerstats;
509 spin_unlock(&cpufreq_stats_lock);
512 static int compare_for_sort(const void *lhs_ptr, const void *rhs_ptr)
514 unsigned int lhs = *(const unsigned int *)(lhs_ptr);
515 unsigned int rhs = *(const unsigned int *)(rhs_ptr);
523 static bool check_all_freq_table(unsigned int freq)
526 for (i = 0; i < all_freq_table->table_size; i++) {
527 if (freq == all_freq_table->freq_table[i])
533 static void create_all_freq_table(void)
535 all_freq_table = kzalloc(sizeof(struct all_freq_table),
538 pr_warn("could not allocate memory for all_freq_table\n");
542 static void add_all_freq_table(unsigned int freq)
545 size = sizeof(unsigned int) * (all_freq_table->table_size + 1);
546 all_freq_table->freq_table = krealloc(all_freq_table->freq_table,
548 if (IS_ERR(all_freq_table->freq_table)) {
549 pr_warn("Could not reallocate memory for freq_table\n");
550 all_freq_table->freq_table = NULL;
553 all_freq_table->freq_table[all_freq_table->table_size++] = freq;
556 static void cpufreq_allstats_create(unsigned int cpu,
557 struct cpufreq_frequency_table *table, int count)
560 unsigned int alloc_size;
561 struct all_cpufreq_stats *all_stat;
562 bool sort_needed = false;
564 all_stat = kzalloc(sizeof(struct all_cpufreq_stats),
567 pr_warn("Cannot allocate memory for cpufreq stats\n");
571 /*Allocate memory for freq table per cpu as well as clockticks per freq*/
572 alloc_size = count * sizeof(int) + count * sizeof(cputime64_t);
573 all_stat->time_in_state = kzalloc(alloc_size, GFP_KERNEL);
574 if (!all_stat->time_in_state) {
575 pr_warn("Cannot allocate memory for cpufreq time_in_state\n");
580 all_stat->freq_table = (unsigned int *)
581 (all_stat->time_in_state + count);
583 spin_lock(&cpufreq_stats_lock);
584 for (i = 0; table[i].frequency != CPUFREQ_TABLE_END; i++) {
585 unsigned int freq = table[i].frequency;
586 if (freq == CPUFREQ_ENTRY_INVALID)
588 all_stat->freq_table[j++] = freq;
589 if (all_freq_table && !check_all_freq_table(freq)) {
590 add_all_freq_table(freq);
595 sort(all_freq_table->freq_table, all_freq_table->table_size,
596 sizeof(unsigned int), &compare_for_sort, NULL);
597 all_stat->state_num = j;
598 per_cpu(all_cpufreq_stats, cpu) = all_stat;
599 spin_unlock(&cpufreq_stats_lock);
602 static int cpufreq_stat_notifier_policy(struct notifier_block *nb,
603 unsigned long val, void *data)
605 int ret, count = 0, i;
606 struct cpufreq_policy *policy = data;
607 struct cpufreq_frequency_table *table;
608 unsigned int cpu_num, cpu = policy->cpu;
610 if (val == CPUFREQ_UPDATE_POLICY_CPU) {
611 cpufreq_stats_update_policy_cpu(policy);
615 if (val != CPUFREQ_NOTIFY)
617 table = cpufreq_frequency_get_table(cpu);
621 for (i = 0; table[i].frequency != CPUFREQ_TABLE_END; i++) {
622 unsigned int freq = table[i].frequency;
624 if (freq == CPUFREQ_ENTRY_INVALID)
629 if (!per_cpu(all_cpufreq_stats, cpu))
630 cpufreq_allstats_create(cpu, table, count);
632 for_each_possible_cpu(cpu_num) {
633 if (!per_cpu(cpufreq_power_stats, cpu_num))
634 cpufreq_powerstats_create(cpu_num, table, count);
637 ret = cpufreq_stats_create_table(policy, table, count);
643 static int cpufreq_stat_notifier_trans(struct notifier_block *nb,
644 unsigned long val, void *data)
646 struct cpufreq_freqs *freq = data;
647 struct cpufreq_stats *stat;
648 int old_index, new_index;
650 if (val != CPUFREQ_POSTCHANGE)
653 stat = per_cpu(cpufreq_stats_table, freq->cpu);
657 old_index = stat->last_index;
658 new_index = freq_table_get_index(stat, freq->new);
660 /* We can't do stat->time_in_state[-1]= .. */
661 if (old_index == -1 || new_index == -1)
664 cpufreq_stats_update(freq->cpu);
666 if (old_index == new_index)
669 spin_lock(&cpufreq_stats_lock);
670 stat->last_index = new_index;
671 #ifdef CONFIG_CPU_FREQ_STAT_DETAILS
672 stat->trans_table[old_index * stat->max_state + new_index]++;
675 spin_unlock(&cpufreq_stats_lock);
679 static int cpufreq_stats_create_table_cpu(unsigned int cpu)
681 struct cpufreq_policy *policy;
682 struct cpufreq_frequency_table *table;
683 int i, count, cpu_num, ret = -ENODEV;
685 policy = cpufreq_cpu_get(cpu);
689 table = cpufreq_frequency_get_table(cpu);
694 for (i = 0; table[i].frequency != CPUFREQ_TABLE_END; i++) {
695 unsigned int freq = table[i].frequency;
697 if (freq != CPUFREQ_ENTRY_INVALID)
701 if (!per_cpu(all_cpufreq_stats, cpu))
702 cpufreq_allstats_create(cpu, table, count);
704 for_each_possible_cpu(cpu_num) {
705 if (!per_cpu(cpufreq_power_stats, cpu_num))
706 cpufreq_powerstats_create(cpu_num, table, count);
709 ret = cpufreq_stats_create_table(policy, table, count);
712 cpufreq_cpu_put(policy);
716 static int __cpuinit cpufreq_stat_cpu_callback(struct notifier_block *nfb,
717 unsigned long action,
720 unsigned int cpu = (unsigned long)hcpu;
724 case CPU_ONLINE_FROZEN:
725 cpufreq_update_policy(cpu);
727 case CPU_DOWN_PREPARE:
728 case CPU_DOWN_PREPARE_FROZEN:
729 cpufreq_stats_free_sysfs(cpu);
732 case CPU_DEAD_FROZEN:
733 cpufreq_stats_free_table(cpu);
735 case CPU_DOWN_FAILED:
736 case CPU_DOWN_FAILED_FROZEN:
737 cpufreq_stats_create_table_cpu(cpu);
743 /* priority=1 so this will get called before cpufreq_remove_dev */
744 static struct notifier_block cpufreq_stat_cpu_notifier __refdata = {
745 .notifier_call = cpufreq_stat_cpu_callback,
749 static struct notifier_block notifier_policy_block = {
750 .notifier_call = cpufreq_stat_notifier_policy
753 static struct notifier_block notifier_trans_block = {
754 .notifier_call = cpufreq_stat_notifier_trans
757 static int cpufreq_stats_setup(void)
762 spin_lock_init(&cpufreq_stats_lock);
763 ret = cpufreq_register_notifier(¬ifier_policy_block,
764 CPUFREQ_POLICY_NOTIFIER);
768 register_hotcpu_notifier(&cpufreq_stat_cpu_notifier);
769 for_each_online_cpu(cpu)
770 cpufreq_update_policy(cpu);
772 ret = cpufreq_register_notifier(¬ifier_trans_block,
773 CPUFREQ_TRANSITION_NOTIFIER);
775 cpufreq_unregister_notifier(¬ifier_policy_block,
776 CPUFREQ_POLICY_NOTIFIER);
777 unregister_hotcpu_notifier(&cpufreq_stat_cpu_notifier);
778 for_each_online_cpu(cpu)
779 cpufreq_stats_free_table(cpu);
783 create_all_freq_table();
784 ret = sysfs_create_file(cpufreq_global_kobject,
785 &_attr_all_time_in_state.attr);
787 pr_warn("Cannot create sysfs file for cpufreq stats\n");
789 ret = sysfs_create_file(cpufreq_global_kobject,
790 &_attr_current_in_state.attr);
792 pr_warn("Cannot create sysfs file for cpufreq current stats\n");
797 static void cpufreq_stats_cleanup(void)
801 cpufreq_unregister_notifier(¬ifier_policy_block,
802 CPUFREQ_POLICY_NOTIFIER);
803 cpufreq_unregister_notifier(¬ifier_trans_block,
804 CPUFREQ_TRANSITION_NOTIFIER);
805 unregister_hotcpu_notifier(&cpufreq_stat_cpu_notifier);
806 for_each_online_cpu(cpu) {
807 cpufreq_stats_free_table(cpu);
808 cpufreq_stats_free_sysfs(cpu);
810 cpufreq_allstats_free();
811 cpufreq_powerstats_free();
814 #ifdef CONFIG_BL_SWITCHER
815 static int cpufreq_stats_switcher_notifier(struct notifier_block *nfb,
816 unsigned long action, void *_arg)
819 case BL_NOTIFY_PRE_ENABLE:
820 case BL_NOTIFY_PRE_DISABLE:
821 cpufreq_stats_cleanup();
824 case BL_NOTIFY_POST_ENABLE:
825 case BL_NOTIFY_POST_DISABLE:
826 cpufreq_stats_setup();
836 static struct notifier_block switcher_notifier = {
837 .notifier_call = cpufreq_stats_switcher_notifier,
841 static int __init cpufreq_stats_init(void)
844 spin_lock_init(&cpufreq_stats_lock);
846 ret = cpufreq_stats_setup();
847 #ifdef CONFIG_BL_SWITCHER
849 bL_switcher_register_notifier(&switcher_notifier);
854 static void __exit cpufreq_stats_exit(void)
856 #ifdef CONFIG_BL_SWITCHER
857 bL_switcher_unregister_notifier(&switcher_notifier);
859 cpufreq_stats_cleanup();
862 MODULE_AUTHOR("Zou Nan hai <nanhai.zou@intel.com>");
863 MODULE_DESCRIPTION("'cpufreq_stats' - A driver to export cpufreq stats "
864 "through sysfs filesystem");
865 MODULE_LICENSE("GPL");
867 module_init(cpufreq_stats_init);
868 module_exit(cpufreq_stats_exit);