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>
25 #include <asm/cputime.h>
26 #ifdef CONFIG_BL_SWITCHER
27 #include <asm/bL_switcher.h>
30 static spinlock_t cpufreq_stats_lock;
32 struct cpufreq_stats {
34 unsigned int total_trans;
35 unsigned long long last_time;
36 unsigned int max_state;
37 unsigned int state_num;
38 unsigned int last_index;
40 unsigned int *freq_table;
41 #ifdef CONFIG_CPU_FREQ_STAT_DETAILS
42 unsigned int *trans_table;
46 struct all_cpufreq_stats {
47 unsigned int state_num;
48 cputime64_t *time_in_state;
49 unsigned int *freq_table;
52 struct all_freq_table {
53 unsigned int *freq_table;
54 unsigned int table_size;
57 static struct all_freq_table *all_freq_table;
59 static DEFINE_PER_CPU(struct all_cpufreq_stats *, all_cpufreq_stats);
60 static DEFINE_PER_CPU(struct cpufreq_stats *, cpufreq_stats_table);
62 struct cpufreq_stats_attribute {
63 struct attribute attr;
64 ssize_t(*show) (struct cpufreq_stats *, char *);
67 static int cpufreq_stats_update(unsigned int cpu)
69 struct cpufreq_stats *stat;
70 struct all_cpufreq_stats *all_stat;
71 unsigned long long cur_time;
73 cur_time = get_jiffies_64();
74 spin_lock(&cpufreq_stats_lock);
75 stat = per_cpu(cpufreq_stats_table, cpu);
76 all_stat = per_cpu(all_cpufreq_stats, cpu);
78 spin_unlock(&cpufreq_stats_lock);
81 if (stat->time_in_state) {
82 stat->time_in_state[stat->last_index] +=
83 cur_time - stat->last_time;
85 all_stat->time_in_state[stat->last_index] +=
86 cur_time - stat->last_time;
88 stat->last_time = cur_time;
89 spin_unlock(&cpufreq_stats_lock);
93 static ssize_t show_total_trans(struct cpufreq_policy *policy, char *buf)
95 struct cpufreq_stats *stat = per_cpu(cpufreq_stats_table, policy->cpu);
98 return sprintf(buf, "%d\n",
99 per_cpu(cpufreq_stats_table, stat->cpu)->total_trans);
102 static ssize_t show_time_in_state(struct cpufreq_policy *policy, char *buf)
106 struct cpufreq_stats *stat = per_cpu(cpufreq_stats_table, policy->cpu);
109 cpufreq_stats_update(stat->cpu);
110 for (i = 0; i < stat->state_num; i++) {
111 len += sprintf(buf + len, "%u %llu\n", stat->freq_table[i],
113 jiffies_64_to_clock_t(stat->time_in_state[i]));
118 static int get_index_all_cpufreq_stat(struct all_cpufreq_stats *all_stat,
124 for (i = 0; i < all_stat->state_num; i++) {
125 if (all_stat->freq_table[i] == freq)
131 static ssize_t show_all_time_in_state(struct kobject *kobj,
132 struct kobj_attribute *attr, char *buf)
135 unsigned int i, cpu, freq, index;
136 struct all_cpufreq_stats *all_stat;
137 struct cpufreq_policy *policy;
139 len += scnprintf(buf + len, PAGE_SIZE - len, "freq\t\t");
140 for_each_possible_cpu(cpu) {
141 len += scnprintf(buf + len, PAGE_SIZE - len, "cpu%d\t\t", cpu);
143 cpufreq_stats_update(cpu);
148 for (i = 0; i < all_freq_table->table_size; i++) {
149 freq = all_freq_table->freq_table[i];
150 len += scnprintf(buf + len, PAGE_SIZE - len, "\n%u\t\t", freq);
151 for_each_possible_cpu(cpu) {
152 policy = cpufreq_cpu_get(cpu);
155 all_stat = per_cpu(all_cpufreq_stats, policy->cpu);
156 index = get_index_all_cpufreq_stat(all_stat, freq);
158 len += scnprintf(buf + len, PAGE_SIZE - len,
159 "%llu\t\t", (unsigned long long)
160 cputime64_to_clock_t(all_stat->time_in_state[index]));
162 len += scnprintf(buf + len, PAGE_SIZE - len,
165 cpufreq_cpu_put(policy);
170 len += scnprintf(buf + len, PAGE_SIZE - len, "\n");
174 #ifdef CONFIG_CPU_FREQ_STAT_DETAILS
175 static ssize_t show_trans_table(struct cpufreq_policy *policy, char *buf)
180 struct cpufreq_stats *stat = per_cpu(cpufreq_stats_table, policy->cpu);
183 cpufreq_stats_update(stat->cpu);
184 len += snprintf(buf + len, PAGE_SIZE - len, " From : To\n");
185 len += snprintf(buf + len, PAGE_SIZE - len, " : ");
186 for (i = 0; i < stat->state_num; i++) {
187 if (len >= PAGE_SIZE)
189 len += snprintf(buf + len, PAGE_SIZE - len, "%9u ",
190 stat->freq_table[i]);
192 if (len >= PAGE_SIZE)
195 len += snprintf(buf + len, PAGE_SIZE - len, "\n");
197 for (i = 0; i < stat->state_num; i++) {
198 if (len >= PAGE_SIZE)
201 len += snprintf(buf + len, PAGE_SIZE - len, "%9u: ",
202 stat->freq_table[i]);
204 for (j = 0; j < stat->state_num; j++) {
205 if (len >= PAGE_SIZE)
207 len += snprintf(buf + len, PAGE_SIZE - len, "%9u ",
208 stat->trans_table[i*stat->max_state+j]);
210 if (len >= PAGE_SIZE)
212 len += snprintf(buf + len, PAGE_SIZE - len, "\n");
214 if (len >= PAGE_SIZE)
218 cpufreq_freq_attr_ro(trans_table);
221 cpufreq_freq_attr_ro(total_trans);
222 cpufreq_freq_attr_ro(time_in_state);
224 static struct attribute *default_attrs[] = {
227 #ifdef CONFIG_CPU_FREQ_STAT_DETAILS
232 static struct attribute_group stats_attr_group = {
233 .attrs = default_attrs,
237 static struct kobj_attribute _attr_all_time_in_state = __ATTR(all_time_in_state,
238 0444, show_all_time_in_state, NULL);
240 static int freq_table_get_index(struct cpufreq_stats *stat, unsigned int freq)
243 for (index = 0; index < stat->max_state; index++)
244 if (stat->freq_table[index] == freq)
249 /* should be called late in the CPU removal sequence so that the stats
250 * memory is still available in case someone tries to use it.
252 static void cpufreq_stats_free_table(unsigned int cpu)
254 struct cpufreq_stats *stat = per_cpu(cpufreq_stats_table, cpu);
257 pr_debug("%s: Free stat table\n", __func__);
258 kfree(stat->time_in_state);
260 per_cpu(cpufreq_stats_table, cpu) = NULL;
264 /* must be called early in the CPU removal sequence (before
265 * cpufreq_remove_dev) so that policy is still valid.
267 static void cpufreq_stats_free_sysfs(unsigned int cpu)
269 struct cpufreq_policy *policy = cpufreq_cpu_get(cpu);
274 if (!cpufreq_frequency_get_table(cpu))
277 if (!policy_is_shared(policy)) {
278 pr_debug("%s: Free sysfs stat\n", __func__);
279 sysfs_remove_group(&policy->kobj, &stats_attr_group);
283 cpufreq_cpu_put(policy);
286 static void cpufreq_allstats_free(void)
289 struct all_cpufreq_stats *all_stat;
291 sysfs_remove_file(cpufreq_global_kobject,
292 &_attr_all_time_in_state.attr);
294 for_each_possible_cpu(cpu) {
295 all_stat = per_cpu(all_cpufreq_stats, cpu);
298 kfree(all_stat->time_in_state);
300 per_cpu(all_cpufreq_stats, cpu) = NULL;
302 if (all_freq_table) {
303 kfree(all_freq_table->freq_table);
304 kfree(all_freq_table);
305 all_freq_table = NULL;
309 static int cpufreq_stats_create_table(struct cpufreq_policy *policy,
310 struct cpufreq_frequency_table *table)
312 unsigned int i, j, count = 0, ret = 0;
313 struct cpufreq_stats *stat;
314 struct cpufreq_policy *data;
315 unsigned int alloc_size;
316 unsigned int cpu = policy->cpu;
317 if (per_cpu(cpufreq_stats_table, cpu))
319 stat = kzalloc(sizeof(struct cpufreq_stats), GFP_KERNEL);
323 data = cpufreq_cpu_get(cpu);
329 ret = sysfs_create_group(&data->kobj, &stats_attr_group);
334 per_cpu(cpufreq_stats_table, cpu) = stat;
336 for (i = 0; table[i].frequency != CPUFREQ_TABLE_END; i++) {
337 unsigned int freq = table[i].frequency;
338 if (freq == CPUFREQ_ENTRY_INVALID)
343 alloc_size = count * sizeof(int) + count * sizeof(u64);
345 #ifdef CONFIG_CPU_FREQ_STAT_DETAILS
346 alloc_size += count * count * sizeof(int);
348 stat->max_state = count;
349 stat->time_in_state = kzalloc(alloc_size, GFP_KERNEL);
350 if (!stat->time_in_state) {
354 stat->freq_table = (unsigned int *)(stat->time_in_state + count);
356 #ifdef CONFIG_CPU_FREQ_STAT_DETAILS
357 stat->trans_table = stat->freq_table + count;
360 for (i = 0; table[i].frequency != CPUFREQ_TABLE_END; i++) {
361 unsigned int freq = table[i].frequency;
362 if (freq == CPUFREQ_ENTRY_INVALID)
364 if (freq_table_get_index(stat, freq) == -1)
365 stat->freq_table[j++] = freq;
368 spin_lock(&cpufreq_stats_lock);
369 stat->last_time = get_jiffies_64();
370 stat->last_index = freq_table_get_index(stat, policy->cur);
371 spin_unlock(&cpufreq_stats_lock);
372 cpufreq_cpu_put(data);
375 cpufreq_cpu_put(data);
378 per_cpu(cpufreq_stats_table, cpu) = NULL;
382 static void cpufreq_stats_update_policy_cpu(struct cpufreq_policy *policy)
384 struct cpufreq_stats *stat = per_cpu(cpufreq_stats_table,
387 pr_debug("Updating stats_table for new_cpu %u from last_cpu %u\n",
388 policy->cpu, policy->last_cpu);
389 per_cpu(cpufreq_stats_table, policy->cpu) = per_cpu(cpufreq_stats_table,
391 per_cpu(cpufreq_stats_table, policy->last_cpu) = NULL;
392 stat->cpu = policy->cpu;
395 static int compare_for_sort(const void *lhs_ptr, const void *rhs_ptr)
397 unsigned int lhs = *(const unsigned int *)(lhs_ptr);
398 unsigned int rhs = *(const unsigned int *)(rhs_ptr);
406 static bool check_all_freq_table(unsigned int freq)
409 for (i = 0; i < all_freq_table->table_size; i++) {
410 if (freq == all_freq_table->freq_table[i])
416 static void create_all_freq_table(void)
418 all_freq_table = kzalloc(sizeof(struct all_freq_table),
421 pr_warn("could not allocate memory for all_freq_table\n");
425 static void add_all_freq_table(unsigned int freq)
428 size = sizeof(unsigned int) * (all_freq_table->table_size + 1);
429 all_freq_table->freq_table = krealloc(all_freq_table->freq_table,
431 if (IS_ERR(all_freq_table->freq_table)) {
432 pr_warn("Could not reallocate memory for freq_table\n");
433 all_freq_table->freq_table = NULL;
436 all_freq_table->freq_table[all_freq_table->table_size++] = freq;
439 static void cpufreq_allstats_create(unsigned int cpu)
442 unsigned int alloc_size, count = 0;
443 struct cpufreq_frequency_table *table = cpufreq_frequency_get_table(cpu);
444 struct all_cpufreq_stats *all_stat;
445 bool sort_needed = false;
450 for (i = 0; table[i].frequency != CPUFREQ_TABLE_END; i++) {
451 unsigned int freq = table[i].frequency;
452 if (freq == CPUFREQ_ENTRY_INVALID)
457 all_stat = kzalloc(sizeof(struct all_cpufreq_stats),
460 pr_warn("Cannot allocate memory for cpufreq stats\n");
464 /*Allocate memory for freq table per cpu as well as clockticks per freq*/
465 alloc_size = count * sizeof(int) + count * sizeof(cputime64_t);
466 all_stat->time_in_state = kzalloc(alloc_size, GFP_KERNEL);
467 if (!all_stat->time_in_state) {
468 pr_warn("Cannot allocate memory for cpufreq time_in_state\n");
473 all_stat->freq_table = (unsigned int *)
474 (all_stat->time_in_state + count);
476 spin_lock(&cpufreq_stats_lock);
477 for (i = 0; table[i].frequency != CPUFREQ_TABLE_END; i++) {
478 unsigned int freq = table[i].frequency;
479 if (freq == CPUFREQ_ENTRY_INVALID)
481 all_stat->freq_table[j++] = freq;
482 if (all_freq_table && !check_all_freq_table(freq)) {
483 add_all_freq_table(freq);
488 sort(all_freq_table->freq_table, all_freq_table->table_size,
489 sizeof(unsigned int), &compare_for_sort, NULL);
490 all_stat->state_num = j;
491 per_cpu(all_cpufreq_stats, cpu) = all_stat;
492 spin_unlock(&cpufreq_stats_lock);
495 static int cpufreq_stat_notifier_policy(struct notifier_block *nb,
496 unsigned long val, void *data)
499 struct cpufreq_policy *policy = data;
500 struct cpufreq_frequency_table *table;
501 unsigned int cpu = policy->cpu;
503 if (val == CPUFREQ_UPDATE_POLICY_CPU) {
504 cpufreq_stats_update_policy_cpu(policy);
508 if (val != CPUFREQ_NOTIFY)
510 table = cpufreq_frequency_get_table(cpu);
514 if (!per_cpu(all_cpufreq_stats, cpu))
515 cpufreq_allstats_create(cpu);
517 ret = cpufreq_stats_create_table(policy, table);
523 static int cpufreq_stat_notifier_trans(struct notifier_block *nb,
524 unsigned long val, void *data)
526 struct cpufreq_freqs *freq = data;
527 struct cpufreq_stats *stat;
528 int old_index, new_index;
530 if (val != CPUFREQ_POSTCHANGE)
533 stat = per_cpu(cpufreq_stats_table, freq->cpu);
537 old_index = stat->last_index;
538 new_index = freq_table_get_index(stat, freq->new);
540 /* We can't do stat->time_in_state[-1]= .. */
541 if (old_index == -1 || new_index == -1)
544 cpufreq_stats_update(freq->cpu);
546 if (old_index == new_index)
549 spin_lock(&cpufreq_stats_lock);
550 stat->last_index = new_index;
551 #ifdef CONFIG_CPU_FREQ_STAT_DETAILS
552 stat->trans_table[old_index * stat->max_state + new_index]++;
555 spin_unlock(&cpufreq_stats_lock);
559 static int cpufreq_stats_create_table_cpu(unsigned int cpu)
561 struct cpufreq_policy *policy;
562 struct cpufreq_frequency_table *table;
565 policy = cpufreq_cpu_get(cpu);
569 table = cpufreq_frequency_get_table(cpu);
573 if (!per_cpu(all_cpufreq_stats, cpu))
574 cpufreq_allstats_create(cpu);
576 ret = cpufreq_stats_create_table(policy, table);
579 cpufreq_cpu_put(policy);
583 static int __cpuinit cpufreq_stat_cpu_callback(struct notifier_block *nfb,
584 unsigned long action,
587 unsigned int cpu = (unsigned long)hcpu;
591 case CPU_ONLINE_FROZEN:
592 cpufreq_update_policy(cpu);
594 case CPU_DOWN_PREPARE:
595 case CPU_DOWN_PREPARE_FROZEN:
596 cpufreq_stats_free_sysfs(cpu);
599 case CPU_DEAD_FROZEN:
600 cpufreq_stats_free_table(cpu);
602 case CPU_DOWN_FAILED:
603 case CPU_DOWN_FAILED_FROZEN:
604 cpufreq_stats_create_table_cpu(cpu);
610 /* priority=1 so this will get called before cpufreq_remove_dev */
611 static struct notifier_block cpufreq_stat_cpu_notifier __refdata = {
612 .notifier_call = cpufreq_stat_cpu_callback,
616 static struct notifier_block notifier_policy_block = {
617 .notifier_call = cpufreq_stat_notifier_policy
620 static struct notifier_block notifier_trans_block = {
621 .notifier_call = cpufreq_stat_notifier_trans
624 static int cpufreq_stats_setup(void)
629 spin_lock_init(&cpufreq_stats_lock);
630 ret = cpufreq_register_notifier(¬ifier_policy_block,
631 CPUFREQ_POLICY_NOTIFIER);
635 register_hotcpu_notifier(&cpufreq_stat_cpu_notifier);
636 for_each_online_cpu(cpu)
637 cpufreq_update_policy(cpu);
639 ret = cpufreq_register_notifier(¬ifier_trans_block,
640 CPUFREQ_TRANSITION_NOTIFIER);
642 cpufreq_unregister_notifier(¬ifier_policy_block,
643 CPUFREQ_POLICY_NOTIFIER);
644 unregister_hotcpu_notifier(&cpufreq_stat_cpu_notifier);
645 for_each_online_cpu(cpu)
646 cpufreq_stats_free_table(cpu);
650 create_all_freq_table();
651 ret = sysfs_create_file(cpufreq_global_kobject,
652 &_attr_all_time_in_state.attr);
654 pr_warn("Error creating sysfs file for cpufreq stats\n");
659 static void cpufreq_stats_cleanup(void)
663 cpufreq_unregister_notifier(¬ifier_policy_block,
664 CPUFREQ_POLICY_NOTIFIER);
665 cpufreq_unregister_notifier(¬ifier_trans_block,
666 CPUFREQ_TRANSITION_NOTIFIER);
667 unregister_hotcpu_notifier(&cpufreq_stat_cpu_notifier);
668 for_each_online_cpu(cpu) {
669 cpufreq_stats_free_table(cpu);
670 cpufreq_stats_free_sysfs(cpu);
672 cpufreq_allstats_free();
675 #ifdef CONFIG_BL_SWITCHER
676 static int cpufreq_stats_switcher_notifier(struct notifier_block *nfb,
677 unsigned long action, void *_arg)
680 case BL_NOTIFY_PRE_ENABLE:
681 case BL_NOTIFY_PRE_DISABLE:
682 cpufreq_stats_cleanup();
685 case BL_NOTIFY_POST_ENABLE:
686 case BL_NOTIFY_POST_DISABLE:
687 cpufreq_stats_setup();
697 static struct notifier_block switcher_notifier = {
698 .notifier_call = cpufreq_stats_switcher_notifier,
702 static int __init cpufreq_stats_init(void)
705 spin_lock_init(&cpufreq_stats_lock);
707 ret = cpufreq_stats_setup();
708 #ifdef CONFIG_BL_SWITCHER
710 bL_switcher_register_notifier(&switcher_notifier);
715 static void __exit cpufreq_stats_exit(void)
717 #ifdef CONFIG_BL_SWITCHER
718 bL_switcher_unregister_notifier(&switcher_notifier);
720 cpufreq_stats_cleanup();
723 MODULE_AUTHOR("Zou Nan hai <nanhai.zou@intel.com>");
724 MODULE_DESCRIPTION("'cpufreq_stats' - A driver to export cpufreq stats "
725 "through sysfs filesystem");
726 MODULE_LICENSE("GPL");
728 module_init(cpufreq_stats_init);
729 module_exit(cpufreq_stats_exit);