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/kernel.h> |
5a0e3ad6 | 13 | #include <linux/slab.h> |
1da177e4 LT |
14 | #include <linux/cpu.h> |
15 | #include <linux/sysfs.h> | |
16 | #include <linux/cpufreq.h> | |
5c720d37 | 17 | #include <linux/module.h> |
1da177e4 LT |
18 | #include <linux/jiffies.h> |
19 | #include <linux/percpu.h> | |
20 | #include <linux/kobject.h> | |
21 | #include <linux/spinlock.h> | |
c32b6b8e | 22 | #include <linux/notifier.h> |
58f1df25 | 23 | #include <asm/cputime.h> |
1da177e4 LT |
24 | |
25 | static spinlock_t cpufreq_stats_lock; | |
26 | ||
1da177e4 LT |
27 | struct cpufreq_stats { |
28 | unsigned int cpu; | |
29 | unsigned int total_trans; | |
bb176f7d | 30 | unsigned long long last_time; |
1da177e4 LT |
31 | unsigned int max_state; |
32 | unsigned int state_num; | |
33 | unsigned int last_index; | |
1e7586a1 | 34 | u64 *time_in_state; |
1da177e4 LT |
35 | unsigned int *freq_table; |
36 | #ifdef CONFIG_CPU_FREQ_STAT_DETAILS | |
37 | unsigned int *trans_table; | |
38 | #endif | |
39 | }; | |
40 | ||
7a6aedfa | 41 | static DEFINE_PER_CPU(struct cpufreq_stats *, cpufreq_stats_table); |
1da177e4 LT |
42 | |
43 | struct cpufreq_stats_attribute { | |
44 | struct attribute attr; | |
45 | ssize_t(*show) (struct cpufreq_stats *, char *); | |
46 | }; | |
47 | ||
0a829c5a | 48 | static int cpufreq_stats_update(unsigned int cpu) |
1da177e4 LT |
49 | { |
50 | struct cpufreq_stats *stat; | |
58f1df25 VP |
51 | unsigned long long cur_time; |
52 | ||
53 | cur_time = get_jiffies_64(); | |
1da177e4 | 54 | spin_lock(&cpufreq_stats_lock); |
7a6aedfa | 55 | stat = per_cpu(cpufreq_stats_table, cpu); |
1da177e4 | 56 | if (stat->time_in_state) |
64861634 MS |
57 | stat->time_in_state[stat->last_index] += |
58 | cur_time - stat->last_time; | |
58f1df25 | 59 | stat->last_time = cur_time; |
1da177e4 LT |
60 | spin_unlock(&cpufreq_stats_lock); |
61 | return 0; | |
62 | } | |
63 | ||
0a829c5a | 64 | static ssize_t show_total_trans(struct cpufreq_policy *policy, char *buf) |
1da177e4 | 65 | { |
7a6aedfa | 66 | struct cpufreq_stats *stat = per_cpu(cpufreq_stats_table, policy->cpu); |
511e9ee1 | 67 | if (!stat) |
1da177e4 LT |
68 | return 0; |
69 | return sprintf(buf, "%d\n", | |
7a6aedfa | 70 | per_cpu(cpufreq_stats_table, stat->cpu)->total_trans); |
1da177e4 LT |
71 | } |
72 | ||
0a829c5a | 73 | static ssize_t show_time_in_state(struct cpufreq_policy *policy, char *buf) |
1da177e4 LT |
74 | { |
75 | ssize_t len = 0; | |
76 | int i; | |
7a6aedfa | 77 | struct cpufreq_stats *stat = per_cpu(cpufreq_stats_table, policy->cpu); |
511e9ee1 | 78 | if (!stat) |
1da177e4 LT |
79 | return 0; |
80 | cpufreq_stats_update(stat->cpu); | |
81 | for (i = 0; i < stat->state_num; i++) { | |
32ee8c3e | 82 | len += sprintf(buf + len, "%u %llu\n", stat->freq_table[i], |
0a829c5a DJ |
83 | (unsigned long long) |
84 | cputime64_to_clock_t(stat->time_in_state[i])); | |
1da177e4 LT |
85 | } |
86 | return len; | |
87 | } | |
88 | ||
89 | #ifdef CONFIG_CPU_FREQ_STAT_DETAILS | |
0a829c5a | 90 | static ssize_t show_trans_table(struct cpufreq_policy *policy, char *buf) |
1da177e4 LT |
91 | { |
92 | ssize_t len = 0; | |
93 | int i, j; | |
94 | ||
7a6aedfa | 95 | struct cpufreq_stats *stat = per_cpu(cpufreq_stats_table, policy->cpu); |
511e9ee1 | 96 | if (!stat) |
1da177e4 LT |
97 | return 0; |
98 | cpufreq_stats_update(stat->cpu); | |
58f1df25 VP |
99 | len += snprintf(buf + len, PAGE_SIZE - len, " From : To\n"); |
100 | len += snprintf(buf + len, PAGE_SIZE - len, " : "); | |
101 | for (i = 0; i < stat->state_num; i++) { | |
102 | if (len >= PAGE_SIZE) | |
103 | break; | |
104 | len += snprintf(buf + len, PAGE_SIZE - len, "%9u ", | |
105 | stat->freq_table[i]); | |
106 | } | |
107 | if (len >= PAGE_SIZE) | |
25aca347 | 108 | return PAGE_SIZE; |
58f1df25 VP |
109 | |
110 | len += snprintf(buf + len, PAGE_SIZE - len, "\n"); | |
111 | ||
1da177e4 LT |
112 | for (i = 0; i < stat->state_num; i++) { |
113 | if (len >= PAGE_SIZE) | |
114 | break; | |
58f1df25 VP |
115 | |
116 | len += snprintf(buf + len, PAGE_SIZE - len, "%9u: ", | |
1da177e4 LT |
117 | stat->freq_table[i]); |
118 | ||
bb176f7d | 119 | for (j = 0; j < stat->state_num; j++) { |
1da177e4 LT |
120 | if (len >= PAGE_SIZE) |
121 | break; | |
58f1df25 | 122 | len += snprintf(buf + len, PAGE_SIZE - len, "%9u ", |
1da177e4 LT |
123 | stat->trans_table[i*stat->max_state+j]); |
124 | } | |
25aca347 CEB |
125 | if (len >= PAGE_SIZE) |
126 | break; | |
1da177e4 LT |
127 | len += snprintf(buf + len, PAGE_SIZE - len, "\n"); |
128 | } | |
25aca347 CEB |
129 | if (len >= PAGE_SIZE) |
130 | return PAGE_SIZE; | |
1da177e4 LT |
131 | return len; |
132 | } | |
df18e504 | 133 | cpufreq_freq_attr_ro(trans_table); |
1da177e4 LT |
134 | #endif |
135 | ||
df18e504 VK |
136 | cpufreq_freq_attr_ro(total_trans); |
137 | cpufreq_freq_attr_ro(time_in_state); | |
1da177e4 LT |
138 | |
139 | static struct attribute *default_attrs[] = { | |
df18e504 VK |
140 | &total_trans.attr, |
141 | &time_in_state.attr, | |
1da177e4 | 142 | #ifdef CONFIG_CPU_FREQ_STAT_DETAILS |
df18e504 | 143 | &trans_table.attr, |
1da177e4 LT |
144 | #endif |
145 | NULL | |
146 | }; | |
147 | static struct attribute_group stats_attr_group = { | |
148 | .attrs = default_attrs, | |
149 | .name = "stats" | |
150 | }; | |
151 | ||
0a829c5a | 152 | static int freq_table_get_index(struct cpufreq_stats *stat, unsigned int freq) |
1da177e4 LT |
153 | { |
154 | int index; | |
155 | for (index = 0; index < stat->max_state; index++) | |
156 | if (stat->freq_table[index] == freq) | |
157 | return index; | |
158 | return -1; | |
159 | } | |
160 | ||
98586ed8 | 161 | /* should be called late in the CPU removal sequence so that the stats |
162 | * memory is still available in case someone tries to use it. | |
163 | */ | |
a3323473 | 164 | static void cpufreq_stats_free_table(unsigned int cpu) |
1da177e4 | 165 | { |
7a6aedfa | 166 | struct cpufreq_stats *stat = per_cpu(cpufreq_stats_table, cpu); |
b8eed8af | 167 | |
1da177e4 | 168 | if (stat) { |
b8eed8af | 169 | pr_debug("%s: Free stat table\n", __func__); |
1da177e4 LT |
170 | kfree(stat->time_in_state); |
171 | kfree(stat); | |
b8eed8af | 172 | per_cpu(cpufreq_stats_table, cpu) = NULL; |
1da177e4 | 173 | } |
98586ed8 | 174 | } |
175 | ||
176 | /* must be called early in the CPU removal sequence (before | |
177 | * cpufreq_remove_dev) so that policy is still valid. | |
178 | */ | |
179 | static void cpufreq_stats_free_sysfs(unsigned int cpu) | |
180 | { | |
181 | struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); | |
633d47d6 | 182 | |
187da1d9 | 183 | if (!policy) |
633d47d6 DB |
184 | return; |
185 | ||
187da1d9 | 186 | if (!cpufreq_frequency_get_table(cpu)) |
187 | goto put_ref; | |
188 | ||
189 | if (!policy_is_shared(policy)) { | |
b8eed8af | 190 | pr_debug("%s: Free sysfs stat\n", __func__); |
98586ed8 | 191 | sysfs_remove_group(&policy->kobj, &stats_attr_group); |
b8eed8af | 192 | } |
187da1d9 | 193 | |
194 | put_ref: | |
195 | cpufreq_cpu_put(policy); | |
1da177e4 LT |
196 | } |
197 | ||
0a829c5a | 198 | static int cpufreq_stats_create_table(struct cpufreq_policy *policy, |
1da177e4 LT |
199 | struct cpufreq_frequency_table *table) |
200 | { | |
201 | unsigned int i, j, count = 0, ret = 0; | |
202 | struct cpufreq_stats *stat; | |
203 | struct cpufreq_policy *data; | |
204 | unsigned int alloc_size; | |
205 | unsigned int cpu = policy->cpu; | |
7a6aedfa | 206 | if (per_cpu(cpufreq_stats_table, cpu)) |
1da177e4 | 207 | return -EBUSY; |
0a829c5a DJ |
208 | stat = kzalloc(sizeof(struct cpufreq_stats), GFP_KERNEL); |
209 | if ((stat) == NULL) | |
1da177e4 | 210 | return -ENOMEM; |
1da177e4 LT |
211 | |
212 | data = cpufreq_cpu_get(cpu); | |
bc7b26fd DJ |
213 | if (data == NULL) { |
214 | ret = -EINVAL; | |
215 | goto error_get_fail; | |
216 | } | |
217 | ||
0a829c5a DJ |
218 | ret = sysfs_create_group(&data->kobj, &stats_attr_group); |
219 | if (ret) | |
1da177e4 LT |
220 | goto error_out; |
221 | ||
222 | stat->cpu = cpu; | |
7a6aedfa | 223 | per_cpu(cpufreq_stats_table, cpu) = stat; |
1da177e4 | 224 | |
0a829c5a | 225 | for (i = 0; table[i].frequency != CPUFREQ_TABLE_END; i++) { |
1da177e4 LT |
226 | unsigned int freq = table[i].frequency; |
227 | if (freq == CPUFREQ_ENTRY_INVALID) | |
228 | continue; | |
229 | count++; | |
230 | } | |
231 | ||
1e7586a1 | 232 | alloc_size = count * sizeof(int) + count * sizeof(u64); |
1da177e4 LT |
233 | |
234 | #ifdef CONFIG_CPU_FREQ_STAT_DETAILS | |
235 | alloc_size += count * count * sizeof(int); | |
236 | #endif | |
237 | stat->max_state = count; | |
e98df50c | 238 | stat->time_in_state = kzalloc(alloc_size, GFP_KERNEL); |
1da177e4 LT |
239 | if (!stat->time_in_state) { |
240 | ret = -ENOMEM; | |
241 | goto error_out; | |
242 | } | |
1da177e4 LT |
243 | stat->freq_table = (unsigned int *)(stat->time_in_state + count); |
244 | ||
245 | #ifdef CONFIG_CPU_FREQ_STAT_DETAILS | |
246 | stat->trans_table = stat->freq_table + count; | |
247 | #endif | |
248 | j = 0; | |
249 | for (i = 0; table[i].frequency != CPUFREQ_TABLE_END; i++) { | |
250 | unsigned int freq = table[i].frequency; | |
251 | if (freq == CPUFREQ_ENTRY_INVALID) | |
252 | continue; | |
253 | if (freq_table_get_index(stat, freq) == -1) | |
254 | stat->freq_table[j++] = freq; | |
255 | } | |
256 | stat->state_num = j; | |
257 | spin_lock(&cpufreq_stats_lock); | |
58f1df25 | 258 | stat->last_time = get_jiffies_64(); |
1da177e4 LT |
259 | stat->last_index = freq_table_get_index(stat, policy->cur); |
260 | spin_unlock(&cpufreq_stats_lock); | |
261 | cpufreq_cpu_put(data); | |
262 | return 0; | |
263 | error_out: | |
264 | cpufreq_cpu_put(data); | |
b7fb358c | 265 | error_get_fail: |
1da177e4 | 266 | kfree(stat); |
7a6aedfa | 267 | per_cpu(cpufreq_stats_table, cpu) = NULL; |
1da177e4 LT |
268 | return ret; |
269 | } | |
270 | ||
b8eed8af VK |
271 | static void cpufreq_stats_update_policy_cpu(struct cpufreq_policy *policy) |
272 | { | |
273 | struct cpufreq_stats *stat = per_cpu(cpufreq_stats_table, | |
274 | policy->last_cpu); | |
275 | ||
276 | pr_debug("Updating stats_table for new_cpu %u from last_cpu %u\n", | |
277 | policy->cpu, policy->last_cpu); | |
278 | per_cpu(cpufreq_stats_table, policy->cpu) = per_cpu(cpufreq_stats_table, | |
279 | policy->last_cpu); | |
280 | per_cpu(cpufreq_stats_table, policy->last_cpu) = NULL; | |
281 | stat->cpu = policy->cpu; | |
282 | } | |
283 | ||
0a829c5a DJ |
284 | static int cpufreq_stat_notifier_policy(struct notifier_block *nb, |
285 | unsigned long val, void *data) | |
1da177e4 LT |
286 | { |
287 | int ret; | |
288 | struct cpufreq_policy *policy = data; | |
289 | struct cpufreq_frequency_table *table; | |
290 | unsigned int cpu = policy->cpu; | |
b8eed8af VK |
291 | |
292 | if (val == CPUFREQ_UPDATE_POLICY_CPU) { | |
293 | cpufreq_stats_update_policy_cpu(policy); | |
294 | return 0; | |
295 | } | |
296 | ||
1da177e4 LT |
297 | if (val != CPUFREQ_NOTIFY) |
298 | return 0; | |
299 | table = cpufreq_frequency_get_table(cpu); | |
300 | if (!table) | |
301 | return 0; | |
0a829c5a DJ |
302 | ret = cpufreq_stats_create_table(policy, table); |
303 | if (ret) | |
1da177e4 LT |
304 | return ret; |
305 | return 0; | |
306 | } | |
307 | ||
0a829c5a DJ |
308 | static int cpufreq_stat_notifier_trans(struct notifier_block *nb, |
309 | unsigned long val, void *data) | |
1da177e4 LT |
310 | { |
311 | struct cpufreq_freqs *freq = data; | |
312 | struct cpufreq_stats *stat; | |
313 | int old_index, new_index; | |
314 | ||
315 | if (val != CPUFREQ_POSTCHANGE) | |
316 | return 0; | |
317 | ||
7a6aedfa | 318 | stat = per_cpu(cpufreq_stats_table, freq->cpu); |
1da177e4 LT |
319 | if (!stat) |
320 | return 0; | |
8edc59d9 | 321 | |
6501faf8 | 322 | old_index = stat->last_index; |
1da177e4 LT |
323 | new_index = freq_table_get_index(stat, freq->new); |
324 | ||
46a310b8 KRW |
325 | /* We can't do stat->time_in_state[-1]= .. */ |
326 | if (old_index == -1 || new_index == -1) | |
1da177e4 LT |
327 | return 0; |
328 | ||
46a310b8 KRW |
329 | cpufreq_stats_update(freq->cpu); |
330 | ||
331 | if (old_index == new_index) | |
8edc59d9 VP |
332 | return 0; |
333 | ||
1da177e4 LT |
334 | spin_lock(&cpufreq_stats_lock); |
335 | stat->last_index = new_index; | |
336 | #ifdef CONFIG_CPU_FREQ_STAT_DETAILS | |
337 | stat->trans_table[old_index * stat->max_state + new_index]++; | |
338 | #endif | |
339 | stat->total_trans++; | |
340 | spin_unlock(&cpufreq_stats_lock); | |
341 | return 0; | |
342 | } | |
343 | ||
2760984f | 344 | static int cpufreq_stat_cpu_callback(struct notifier_block *nfb, |
55395ae7 SS |
345 | unsigned long action, |
346 | void *hcpu) | |
c32b6b8e AR |
347 | { |
348 | unsigned int cpu = (unsigned long)hcpu; | |
349 | ||
350 | switch (action) { | |
351 | case CPU_ONLINE: | |
f51e1eb6 | 352 | case CPU_ONLINE_FROZEN: |
c32b6b8e AR |
353 | cpufreq_update_policy(cpu); |
354 | break; | |
98586ed8 | 355 | case CPU_DOWN_PREPARE: |
aae760ed | 356 | case CPU_DOWN_PREPARE_FROZEN: |
98586ed8 | 357 | cpufreq_stats_free_sysfs(cpu); |
358 | break; | |
c32b6b8e | 359 | case CPU_DEAD: |
aae760ed | 360 | case CPU_DEAD_FROZEN: |
c32b6b8e AR |
361 | cpufreq_stats_free_table(cpu); |
362 | break; | |
363 | } | |
364 | return NOTIFY_OK; | |
365 | } | |
366 | ||
98586ed8 | 367 | /* priority=1 so this will get called before cpufreq_remove_dev */ |
469057d5 | 368 | static struct notifier_block cpufreq_stat_cpu_notifier __refdata = { |
c32b6b8e | 369 | .notifier_call = cpufreq_stat_cpu_callback, |
98586ed8 | 370 | .priority = 1, |
c32b6b8e AR |
371 | }; |
372 | ||
1da177e4 LT |
373 | static struct notifier_block notifier_policy_block = { |
374 | .notifier_call = cpufreq_stat_notifier_policy | |
375 | }; | |
376 | ||
377 | static struct notifier_block notifier_trans_block = { | |
378 | .notifier_call = cpufreq_stat_notifier_trans | |
379 | }; | |
380 | ||
0a829c5a | 381 | static int __init cpufreq_stats_init(void) |
1da177e4 LT |
382 | { |
383 | int ret; | |
384 | unsigned int cpu; | |
c32b6b8e | 385 | |
1da177e4 | 386 | spin_lock_init(&cpufreq_stats_lock); |
0a829c5a DJ |
387 | ret = cpufreq_register_notifier(¬ifier_policy_block, |
388 | CPUFREQ_POLICY_NOTIFIER); | |
389 | if (ret) | |
1da177e4 LT |
390 | return ret; |
391 | ||
56836fb4 KK |
392 | register_hotcpu_notifier(&cpufreq_stat_cpu_notifier); |
393 | for_each_online_cpu(cpu) | |
394 | cpufreq_update_policy(cpu); | |
395 | ||
0a829c5a DJ |
396 | ret = cpufreq_register_notifier(¬ifier_trans_block, |
397 | CPUFREQ_TRANSITION_NOTIFIER); | |
398 | if (ret) { | |
1da177e4 LT |
399 | cpufreq_unregister_notifier(¬ifier_policy_block, |
400 | CPUFREQ_POLICY_NOTIFIER); | |
56836fb4 KK |
401 | unregister_hotcpu_notifier(&cpufreq_stat_cpu_notifier); |
402 | for_each_online_cpu(cpu) | |
403 | cpufreq_stats_free_table(cpu); | |
1da177e4 LT |
404 | return ret; |
405 | } | |
406 | ||
1da177e4 LT |
407 | return 0; |
408 | } | |
0a829c5a | 409 | static void __exit cpufreq_stats_exit(void) |
1da177e4 LT |
410 | { |
411 | unsigned int cpu; | |
c32b6b8e | 412 | |
1da177e4 LT |
413 | cpufreq_unregister_notifier(¬ifier_policy_block, |
414 | CPUFREQ_POLICY_NOTIFIER); | |
415 | cpufreq_unregister_notifier(¬ifier_trans_block, | |
416 | CPUFREQ_TRANSITION_NOTIFIER); | |
65edc68c | 417 | unregister_hotcpu_notifier(&cpufreq_stat_cpu_notifier); |
c32b6b8e | 418 | for_each_online_cpu(cpu) { |
55395ae7 | 419 | cpufreq_stats_free_table(cpu); |
13f06753 | 420 | cpufreq_stats_free_sysfs(cpu); |
c32b6b8e | 421 | } |
1da177e4 LT |
422 | } |
423 | ||
0a829c5a DJ |
424 | MODULE_AUTHOR("Zou Nan hai <nanhai.zou@intel.com>"); |
425 | MODULE_DESCRIPTION("'cpufreq_stats' - A driver to export cpufreq stats " | |
e08f5f5b | 426 | "through sysfs filesystem"); |
0a829c5a | 427 | MODULE_LICENSE("GPL"); |
1da177e4 LT |
428 | |
429 | module_init(cpufreq_stats_init); | |
430 | module_exit(cpufreq_stats_exit); |