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> |
58f1df25 | 16 | #include <asm/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 | ||
7a6aedfa | 34 | static DEFINE_PER_CPU(struct cpufreq_stats *, cpufreq_stats_table); |
1da177e4 LT |
35 | |
36 | struct cpufreq_stats_attribute { | |
37 | struct attribute attr; | |
38 | ssize_t(*show) (struct cpufreq_stats *, char *); | |
39 | }; | |
40 | ||
0a829c5a | 41 | static int cpufreq_stats_update(unsigned int cpu) |
1da177e4 LT |
42 | { |
43 | struct cpufreq_stats *stat; | |
58f1df25 VP |
44 | unsigned long long cur_time; |
45 | ||
46 | cur_time = get_jiffies_64(); | |
1da177e4 | 47 | spin_lock(&cpufreq_stats_lock); |
7a6aedfa | 48 | stat = per_cpu(cpufreq_stats_table, cpu); |
1da177e4 | 49 | if (stat->time_in_state) |
64861634 MS |
50 | stat->time_in_state[stat->last_index] += |
51 | cur_time - stat->last_time; | |
58f1df25 | 52 | stat->last_time = cur_time; |
1da177e4 LT |
53 | spin_unlock(&cpufreq_stats_lock); |
54 | return 0; | |
55 | } | |
56 | ||
0a829c5a | 57 | static ssize_t show_total_trans(struct cpufreq_policy *policy, char *buf) |
1da177e4 | 58 | { |
7a6aedfa | 59 | struct cpufreq_stats *stat = per_cpu(cpufreq_stats_table, policy->cpu); |
511e9ee1 | 60 | if (!stat) |
1da177e4 LT |
61 | return 0; |
62 | return sprintf(buf, "%d\n", | |
7a6aedfa | 63 | per_cpu(cpufreq_stats_table, stat->cpu)->total_trans); |
1da177e4 LT |
64 | } |
65 | ||
0a829c5a | 66 | static ssize_t show_time_in_state(struct cpufreq_policy *policy, char *buf) |
1da177e4 LT |
67 | { |
68 | ssize_t len = 0; | |
69 | int i; | |
7a6aedfa | 70 | struct cpufreq_stats *stat = per_cpu(cpufreq_stats_table, policy->cpu); |
511e9ee1 | 71 | if (!stat) |
1da177e4 LT |
72 | return 0; |
73 | cpufreq_stats_update(stat->cpu); | |
74 | for (i = 0; i < stat->state_num; i++) { | |
32ee8c3e | 75 | len += sprintf(buf + len, "%u %llu\n", stat->freq_table[i], |
0a829c5a | 76 | (unsigned long long) |
a857c0b9 | 77 | jiffies_64_to_clock_t(stat->time_in_state[i])); |
1da177e4 LT |
78 | } |
79 | return len; | |
80 | } | |
81 | ||
82 | #ifdef CONFIG_CPU_FREQ_STAT_DETAILS | |
0a829c5a | 83 | static ssize_t show_trans_table(struct cpufreq_policy *policy, char *buf) |
1da177e4 LT |
84 | { |
85 | ssize_t len = 0; | |
86 | int i, j; | |
87 | ||
7a6aedfa | 88 | struct cpufreq_stats *stat = per_cpu(cpufreq_stats_table, policy->cpu); |
511e9ee1 | 89 | if (!stat) |
1da177e4 LT |
90 | return 0; |
91 | cpufreq_stats_update(stat->cpu); | |
58f1df25 VP |
92 | len += snprintf(buf + len, PAGE_SIZE - len, " From : To\n"); |
93 | len += snprintf(buf + len, PAGE_SIZE - len, " : "); | |
94 | for (i = 0; i < stat->state_num; i++) { | |
95 | if (len >= PAGE_SIZE) | |
96 | break; | |
97 | len += snprintf(buf + len, PAGE_SIZE - len, "%9u ", | |
98 | stat->freq_table[i]); | |
99 | } | |
100 | if (len >= PAGE_SIZE) | |
25aca347 | 101 | return PAGE_SIZE; |
58f1df25 VP |
102 | |
103 | len += snprintf(buf + len, PAGE_SIZE - len, "\n"); | |
104 | ||
1da177e4 LT |
105 | for (i = 0; i < stat->state_num; i++) { |
106 | if (len >= PAGE_SIZE) | |
107 | break; | |
58f1df25 VP |
108 | |
109 | len += snprintf(buf + len, PAGE_SIZE - len, "%9u: ", | |
1da177e4 LT |
110 | stat->freq_table[i]); |
111 | ||
bb176f7d | 112 | for (j = 0; j < stat->state_num; j++) { |
1da177e4 LT |
113 | if (len >= PAGE_SIZE) |
114 | break; | |
58f1df25 | 115 | len += snprintf(buf + len, PAGE_SIZE - len, "%9u ", |
1da177e4 LT |
116 | stat->trans_table[i*stat->max_state+j]); |
117 | } | |
25aca347 CEB |
118 | if (len >= PAGE_SIZE) |
119 | break; | |
1da177e4 LT |
120 | len += snprintf(buf + len, PAGE_SIZE - len, "\n"); |
121 | } | |
25aca347 CEB |
122 | if (len >= PAGE_SIZE) |
123 | return PAGE_SIZE; | |
1da177e4 LT |
124 | return len; |
125 | } | |
df18e504 | 126 | cpufreq_freq_attr_ro(trans_table); |
1da177e4 LT |
127 | #endif |
128 | ||
df18e504 VK |
129 | cpufreq_freq_attr_ro(total_trans); |
130 | cpufreq_freq_attr_ro(time_in_state); | |
1da177e4 LT |
131 | |
132 | static struct attribute *default_attrs[] = { | |
df18e504 VK |
133 | &total_trans.attr, |
134 | &time_in_state.attr, | |
1da177e4 | 135 | #ifdef CONFIG_CPU_FREQ_STAT_DETAILS |
df18e504 | 136 | &trans_table.attr, |
1da177e4 LT |
137 | #endif |
138 | NULL | |
139 | }; | |
140 | static struct attribute_group stats_attr_group = { | |
141 | .attrs = default_attrs, | |
142 | .name = "stats" | |
143 | }; | |
144 | ||
0a829c5a | 145 | static int freq_table_get_index(struct cpufreq_stats *stat, unsigned int freq) |
1da177e4 LT |
146 | { |
147 | int index; | |
148 | for (index = 0; index < stat->max_state; index++) | |
149 | if (stat->freq_table[index] == freq) | |
150 | return index; | |
151 | return -1; | |
152 | } | |
153 | ||
98586ed8 | 154 | /* should be called late in the CPU removal sequence so that the stats |
155 | * memory is still available in case someone tries to use it. | |
156 | */ | |
a3323473 | 157 | static void cpufreq_stats_free_table(unsigned int cpu) |
1da177e4 | 158 | { |
7a6aedfa | 159 | struct cpufreq_stats *stat = per_cpu(cpufreq_stats_table, cpu); |
b8eed8af | 160 | |
1da177e4 | 161 | if (stat) { |
b8eed8af | 162 | pr_debug("%s: Free stat table\n", __func__); |
1da177e4 LT |
163 | kfree(stat->time_in_state); |
164 | kfree(stat); | |
b8eed8af | 165 | per_cpu(cpufreq_stats_table, cpu) = NULL; |
1da177e4 | 166 | } |
98586ed8 | 167 | } |
168 | ||
169 | /* must be called early in the CPU removal sequence (before | |
170 | * cpufreq_remove_dev) so that policy is still valid. | |
171 | */ | |
172 | static void cpufreq_stats_free_sysfs(unsigned int cpu) | |
173 | { | |
174 | struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); | |
633d47d6 | 175 | |
187da1d9 | 176 | if (!policy) |
633d47d6 DB |
177 | return; |
178 | ||
187da1d9 | 179 | if (!cpufreq_frequency_get_table(cpu)) |
180 | goto put_ref; | |
181 | ||
182 | if (!policy_is_shared(policy)) { | |
b8eed8af | 183 | pr_debug("%s: Free sysfs stat\n", __func__); |
98586ed8 | 184 | sysfs_remove_group(&policy->kobj, &stats_attr_group); |
b8eed8af | 185 | } |
187da1d9 | 186 | |
187 | put_ref: | |
188 | cpufreq_cpu_put(policy); | |
1da177e4 LT |
189 | } |
190 | ||
0a829c5a | 191 | static int cpufreq_stats_create_table(struct cpufreq_policy *policy, |
1da177e4 LT |
192 | struct cpufreq_frequency_table *table) |
193 | { | |
194 | unsigned int i, j, count = 0, ret = 0; | |
195 | struct cpufreq_stats *stat; | |
3a3e9e06 | 196 | struct cpufreq_policy *current_policy; |
1da177e4 LT |
197 | unsigned int alloc_size; |
198 | unsigned int cpu = policy->cpu; | |
7a6aedfa | 199 | if (per_cpu(cpufreq_stats_table, cpu)) |
1da177e4 | 200 | return -EBUSY; |
d5b73cd8 | 201 | stat = kzalloc(sizeof(*stat), GFP_KERNEL); |
0a829c5a | 202 | if ((stat) == NULL) |
1da177e4 | 203 | return -ENOMEM; |
1da177e4 | 204 | |
3a3e9e06 VK |
205 | current_policy = cpufreq_cpu_get(cpu); |
206 | if (current_policy == NULL) { | |
bc7b26fd DJ |
207 | ret = -EINVAL; |
208 | goto error_get_fail; | |
209 | } | |
210 | ||
3a3e9e06 | 211 | ret = sysfs_create_group(¤t_policy->kobj, &stats_attr_group); |
0a829c5a | 212 | if (ret) |
1da177e4 LT |
213 | goto error_out; |
214 | ||
215 | stat->cpu = cpu; | |
7a6aedfa | 216 | per_cpu(cpufreq_stats_table, cpu) = stat; |
1da177e4 | 217 | |
0a829c5a | 218 | for (i = 0; table[i].frequency != CPUFREQ_TABLE_END; i++) { |
1da177e4 LT |
219 | unsigned int freq = table[i].frequency; |
220 | if (freq == CPUFREQ_ENTRY_INVALID) | |
221 | continue; | |
222 | count++; | |
223 | } | |
224 | ||
1e7586a1 | 225 | alloc_size = count * sizeof(int) + count * sizeof(u64); |
1da177e4 LT |
226 | |
227 | #ifdef CONFIG_CPU_FREQ_STAT_DETAILS | |
228 | alloc_size += count * count * sizeof(int); | |
229 | #endif | |
230 | stat->max_state = count; | |
e98df50c | 231 | stat->time_in_state = kzalloc(alloc_size, GFP_KERNEL); |
1da177e4 LT |
232 | if (!stat->time_in_state) { |
233 | ret = -ENOMEM; | |
234 | goto error_out; | |
235 | } | |
1da177e4 LT |
236 | stat->freq_table = (unsigned int *)(stat->time_in_state + count); |
237 | ||
238 | #ifdef CONFIG_CPU_FREQ_STAT_DETAILS | |
239 | stat->trans_table = stat->freq_table + count; | |
240 | #endif | |
241 | j = 0; | |
242 | for (i = 0; table[i].frequency != CPUFREQ_TABLE_END; i++) { | |
243 | unsigned int freq = table[i].frequency; | |
244 | if (freq == CPUFREQ_ENTRY_INVALID) | |
245 | continue; | |
246 | if (freq_table_get_index(stat, freq) == -1) | |
247 | stat->freq_table[j++] = freq; | |
248 | } | |
249 | stat->state_num = j; | |
250 | spin_lock(&cpufreq_stats_lock); | |
58f1df25 | 251 | stat->last_time = get_jiffies_64(); |
1da177e4 LT |
252 | stat->last_index = freq_table_get_index(stat, policy->cur); |
253 | spin_unlock(&cpufreq_stats_lock); | |
3a3e9e06 | 254 | cpufreq_cpu_put(current_policy); |
1da177e4 LT |
255 | return 0; |
256 | error_out: | |
3a3e9e06 | 257 | cpufreq_cpu_put(current_policy); |
b7fb358c | 258 | error_get_fail: |
1da177e4 | 259 | kfree(stat); |
7a6aedfa | 260 | per_cpu(cpufreq_stats_table, cpu) = NULL; |
1da177e4 LT |
261 | return ret; |
262 | } | |
263 | ||
b8eed8af VK |
264 | static void cpufreq_stats_update_policy_cpu(struct cpufreq_policy *policy) |
265 | { | |
266 | struct cpufreq_stats *stat = per_cpu(cpufreq_stats_table, | |
267 | policy->last_cpu); | |
268 | ||
269 | pr_debug("Updating stats_table for new_cpu %u from last_cpu %u\n", | |
270 | policy->cpu, policy->last_cpu); | |
271 | per_cpu(cpufreq_stats_table, policy->cpu) = per_cpu(cpufreq_stats_table, | |
272 | policy->last_cpu); | |
273 | per_cpu(cpufreq_stats_table, policy->last_cpu) = NULL; | |
274 | stat->cpu = policy->cpu; | |
275 | } | |
276 | ||
0a829c5a DJ |
277 | static int cpufreq_stat_notifier_policy(struct notifier_block *nb, |
278 | unsigned long val, void *data) | |
1da177e4 LT |
279 | { |
280 | int ret; | |
281 | struct cpufreq_policy *policy = data; | |
282 | struct cpufreq_frequency_table *table; | |
283 | unsigned int cpu = policy->cpu; | |
b8eed8af VK |
284 | |
285 | if (val == CPUFREQ_UPDATE_POLICY_CPU) { | |
286 | cpufreq_stats_update_policy_cpu(policy); | |
287 | return 0; | |
288 | } | |
289 | ||
1da177e4 LT |
290 | if (val != CPUFREQ_NOTIFY) |
291 | return 0; | |
292 | table = cpufreq_frequency_get_table(cpu); | |
293 | if (!table) | |
294 | return 0; | |
0a829c5a DJ |
295 | ret = cpufreq_stats_create_table(policy, table); |
296 | if (ret) | |
1da177e4 LT |
297 | return ret; |
298 | return 0; | |
299 | } | |
300 | ||
0a829c5a DJ |
301 | static int cpufreq_stat_notifier_trans(struct notifier_block *nb, |
302 | unsigned long val, void *data) | |
1da177e4 LT |
303 | { |
304 | struct cpufreq_freqs *freq = data; | |
305 | struct cpufreq_stats *stat; | |
306 | int old_index, new_index; | |
307 | ||
308 | if (val != CPUFREQ_POSTCHANGE) | |
309 | return 0; | |
310 | ||
7a6aedfa | 311 | stat = per_cpu(cpufreq_stats_table, freq->cpu); |
1da177e4 LT |
312 | if (!stat) |
313 | return 0; | |
8edc59d9 | 314 | |
6501faf8 | 315 | old_index = stat->last_index; |
1da177e4 LT |
316 | new_index = freq_table_get_index(stat, freq->new); |
317 | ||
46a310b8 KRW |
318 | /* We can't do stat->time_in_state[-1]= .. */ |
319 | if (old_index == -1 || new_index == -1) | |
1da177e4 LT |
320 | return 0; |
321 | ||
46a310b8 KRW |
322 | cpufreq_stats_update(freq->cpu); |
323 | ||
324 | if (old_index == new_index) | |
8edc59d9 VP |
325 | return 0; |
326 | ||
1da177e4 LT |
327 | spin_lock(&cpufreq_stats_lock); |
328 | stat->last_index = new_index; | |
329 | #ifdef CONFIG_CPU_FREQ_STAT_DETAILS | |
330 | stat->trans_table[old_index * stat->max_state + new_index]++; | |
331 | #endif | |
332 | stat->total_trans++; | |
333 | spin_unlock(&cpufreq_stats_lock); | |
334 | return 0; | |
335 | } | |
336 | ||
2760984f | 337 | static int cpufreq_stat_cpu_callback(struct notifier_block *nfb, |
55395ae7 SS |
338 | unsigned long action, |
339 | void *hcpu) | |
c32b6b8e AR |
340 | { |
341 | unsigned int cpu = (unsigned long)hcpu; | |
342 | ||
343 | switch (action) { | |
98586ed8 | 344 | case CPU_DOWN_PREPARE: |
345 | cpufreq_stats_free_sysfs(cpu); | |
346 | break; | |
c32b6b8e AR |
347 | case CPU_DEAD: |
348 | cpufreq_stats_free_table(cpu); | |
349 | break; | |
350 | } | |
351 | return NOTIFY_OK; | |
352 | } | |
353 | ||
98586ed8 | 354 | /* priority=1 so this will get called before cpufreq_remove_dev */ |
469057d5 | 355 | static struct notifier_block cpufreq_stat_cpu_notifier __refdata = { |
c32b6b8e | 356 | .notifier_call = cpufreq_stat_cpu_callback, |
98586ed8 | 357 | .priority = 1, |
c32b6b8e AR |
358 | }; |
359 | ||
1da177e4 LT |
360 | static struct notifier_block notifier_policy_block = { |
361 | .notifier_call = cpufreq_stat_notifier_policy | |
362 | }; | |
363 | ||
364 | static struct notifier_block notifier_trans_block = { | |
365 | .notifier_call = cpufreq_stat_notifier_trans | |
366 | }; | |
367 | ||
0a829c5a | 368 | static int __init cpufreq_stats_init(void) |
1da177e4 LT |
369 | { |
370 | int ret; | |
371 | unsigned int cpu; | |
c32b6b8e | 372 | |
1da177e4 | 373 | spin_lock_init(&cpufreq_stats_lock); |
0a829c5a DJ |
374 | ret = cpufreq_register_notifier(¬ifier_policy_block, |
375 | CPUFREQ_POLICY_NOTIFIER); | |
376 | if (ret) | |
1da177e4 LT |
377 | return ret; |
378 | ||
56836fb4 | 379 | register_hotcpu_notifier(&cpufreq_stat_cpu_notifier); |
56836fb4 | 380 | |
0a829c5a DJ |
381 | ret = cpufreq_register_notifier(¬ifier_trans_block, |
382 | CPUFREQ_TRANSITION_NOTIFIER); | |
383 | if (ret) { | |
1da177e4 LT |
384 | cpufreq_unregister_notifier(¬ifier_policy_block, |
385 | CPUFREQ_POLICY_NOTIFIER); | |
56836fb4 KK |
386 | unregister_hotcpu_notifier(&cpufreq_stat_cpu_notifier); |
387 | for_each_online_cpu(cpu) | |
388 | cpufreq_stats_free_table(cpu); | |
1da177e4 LT |
389 | return ret; |
390 | } | |
391 | ||
1da177e4 LT |
392 | return 0; |
393 | } | |
0a829c5a | 394 | static void __exit cpufreq_stats_exit(void) |
1da177e4 LT |
395 | { |
396 | unsigned int cpu; | |
c32b6b8e | 397 | |
1da177e4 LT |
398 | cpufreq_unregister_notifier(¬ifier_policy_block, |
399 | CPUFREQ_POLICY_NOTIFIER); | |
400 | cpufreq_unregister_notifier(¬ifier_trans_block, | |
401 | CPUFREQ_TRANSITION_NOTIFIER); | |
65edc68c | 402 | unregister_hotcpu_notifier(&cpufreq_stat_cpu_notifier); |
c32b6b8e | 403 | for_each_online_cpu(cpu) { |
55395ae7 | 404 | cpufreq_stats_free_table(cpu); |
13f06753 | 405 | cpufreq_stats_free_sysfs(cpu); |
c32b6b8e | 406 | } |
1da177e4 LT |
407 | } |
408 | ||
0a829c5a DJ |
409 | MODULE_AUTHOR("Zou Nan hai <nanhai.zou@intel.com>"); |
410 | MODULE_DESCRIPTION("'cpufreq_stats' - A driver to export cpufreq stats " | |
e08f5f5b | 411 | "through sysfs filesystem"); |
0a829c5a | 412 | MODULE_LICENSE("GPL"); |
1da177e4 LT |
413 | |
414 | module_init(cpufreq_stats_init); | |
415 | module_exit(cpufreq_stats_exit); |