Commit | Line | Data |
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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> |
bfc3f028 | 16 | #include <linux/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 | ||
2aba0c1b | 34 | static int cpufreq_stats_update(struct cpufreq_stats *stat) |
1da177e4 | 35 | { |
9531347c | 36 | unsigned long long cur_time = get_jiffies_64(); |
58f1df25 | 37 | |
1da177e4 | 38 | spin_lock(&cpufreq_stats_lock); |
1da177e4 | 39 | if (stat->time_in_state) |
64861634 MS |
40 | stat->time_in_state[stat->last_index] += |
41 | cur_time - stat->last_time; | |
58f1df25 | 42 | stat->last_time = cur_time; |
1da177e4 LT |
43 | spin_unlock(&cpufreq_stats_lock); |
44 | return 0; | |
45 | } | |
46 | ||
0a829c5a | 47 | static ssize_t show_total_trans(struct cpufreq_policy *policy, char *buf) |
1da177e4 | 48 | { |
a9aaf291 | 49 | return sprintf(buf, "%d\n", policy->stats->total_trans); |
1da177e4 LT |
50 | } |
51 | ||
0a829c5a | 52 | static ssize_t show_time_in_state(struct cpufreq_policy *policy, char *buf) |
1da177e4 | 53 | { |
a9aaf291 | 54 | struct cpufreq_stats *stat = policy->stats; |
1da177e4 LT |
55 | ssize_t len = 0; |
56 | int i; | |
a9aaf291 | 57 | |
2aba0c1b | 58 | cpufreq_stats_update(stat); |
1da177e4 | 59 | for (i = 0; i < stat->state_num; i++) { |
32ee8c3e | 60 | len += sprintf(buf + len, "%u %llu\n", stat->freq_table[i], |
0a829c5a | 61 | (unsigned long long) |
a857c0b9 | 62 | jiffies_64_to_clock_t(stat->time_in_state[i])); |
1da177e4 LT |
63 | } |
64 | return len; | |
65 | } | |
66 | ||
67 | #ifdef CONFIG_CPU_FREQ_STAT_DETAILS | |
0a829c5a | 68 | static ssize_t show_trans_table(struct cpufreq_policy *policy, char *buf) |
1da177e4 | 69 | { |
a9aaf291 | 70 | struct cpufreq_stats *stat = policy->stats; |
1da177e4 LT |
71 | ssize_t len = 0; |
72 | int i, j; | |
73 | ||
2aba0c1b | 74 | cpufreq_stats_update(stat); |
58f1df25 VP |
75 | len += snprintf(buf + len, PAGE_SIZE - len, " From : To\n"); |
76 | len += snprintf(buf + len, PAGE_SIZE - len, " : "); | |
77 | for (i = 0; i < stat->state_num; i++) { | |
78 | if (len >= PAGE_SIZE) | |
79 | break; | |
80 | len += snprintf(buf + len, PAGE_SIZE - len, "%9u ", | |
81 | stat->freq_table[i]); | |
82 | } | |
83 | if (len >= PAGE_SIZE) | |
25aca347 | 84 | return PAGE_SIZE; |
58f1df25 VP |
85 | |
86 | len += snprintf(buf + len, PAGE_SIZE - len, "\n"); | |
87 | ||
1da177e4 LT |
88 | for (i = 0; i < stat->state_num; i++) { |
89 | if (len >= PAGE_SIZE) | |
90 | break; | |
58f1df25 VP |
91 | |
92 | len += snprintf(buf + len, PAGE_SIZE - len, "%9u: ", | |
1da177e4 LT |
93 | stat->freq_table[i]); |
94 | ||
bb176f7d | 95 | for (j = 0; j < stat->state_num; j++) { |
1da177e4 LT |
96 | if (len >= PAGE_SIZE) |
97 | break; | |
58f1df25 | 98 | len += snprintf(buf + len, PAGE_SIZE - len, "%9u ", |
1da177e4 LT |
99 | stat->trans_table[i*stat->max_state+j]); |
100 | } | |
25aca347 CEB |
101 | if (len >= PAGE_SIZE) |
102 | break; | |
1da177e4 LT |
103 | len += snprintf(buf + len, PAGE_SIZE - len, "\n"); |
104 | } | |
25aca347 CEB |
105 | if (len >= PAGE_SIZE) |
106 | return PAGE_SIZE; | |
1da177e4 LT |
107 | return len; |
108 | } | |
df18e504 | 109 | cpufreq_freq_attr_ro(trans_table); |
1da177e4 LT |
110 | #endif |
111 | ||
df18e504 VK |
112 | cpufreq_freq_attr_ro(total_trans); |
113 | cpufreq_freq_attr_ro(time_in_state); | |
1da177e4 LT |
114 | |
115 | static struct attribute *default_attrs[] = { | |
df18e504 VK |
116 | &total_trans.attr, |
117 | &time_in_state.attr, | |
1da177e4 | 118 | #ifdef CONFIG_CPU_FREQ_STAT_DETAILS |
df18e504 | 119 | &trans_table.attr, |
1da177e4 LT |
120 | #endif |
121 | NULL | |
122 | }; | |
123 | static struct attribute_group stats_attr_group = { | |
124 | .attrs = default_attrs, | |
125 | .name = "stats" | |
126 | }; | |
127 | ||
0a829c5a | 128 | static int freq_table_get_index(struct cpufreq_stats *stat, unsigned int freq) |
1da177e4 LT |
129 | { |
130 | int index; | |
131 | for (index = 0; index < stat->max_state; index++) | |
132 | if (stat->freq_table[index] == freq) | |
133 | return index; | |
134 | return -1; | |
135 | } | |
136 | ||
2d13594d | 137 | static void __cpufreq_stats_free_table(struct cpufreq_policy *policy) |
1da177e4 | 138 | { |
a9aaf291 | 139 | struct cpufreq_stats *stat = policy->stats; |
b8eed8af | 140 | |
a9aaf291 | 141 | /* Already freed */ |
2d13594d VK |
142 | if (!stat) |
143 | return; | |
144 | ||
145 | pr_debug("%s: Free stat table\n", __func__); | |
146 | ||
147 | sysfs_remove_group(&policy->kobj, &stats_attr_group); | |
148 | kfree(stat->time_in_state); | |
149 | kfree(stat); | |
a9aaf291 | 150 | policy->stats = NULL; |
98586ed8 | 151 | } |
152 | ||
2d13594d | 153 | static void cpufreq_stats_free_table(unsigned int cpu) |
98586ed8 | 154 | { |
2d13594d | 155 | struct cpufreq_policy *policy; |
633d47d6 | 156 | |
2d13594d | 157 | policy = cpufreq_cpu_get(cpu); |
187da1d9 | 158 | if (!policy) |
633d47d6 DB |
159 | return; |
160 | ||
f93dbbbd | 161 | __cpufreq_stats_free_table(policy); |
187da1d9 | 162 | |
187da1d9 | 163 | cpufreq_cpu_put(policy); |
1da177e4 LT |
164 | } |
165 | ||
ad4c2302 | 166 | static int __cpufreq_stats_create_table(struct cpufreq_policy *policy) |
1da177e4 | 167 | { |
041526f9 | 168 | unsigned int i, count = 0, ret = 0; |
1da177e4 | 169 | struct cpufreq_stats *stat; |
1da177e4 LT |
170 | unsigned int alloc_size; |
171 | unsigned int cpu = policy->cpu; | |
041526f9 | 172 | struct cpufreq_frequency_table *pos, *table; |
ad4c2302 SK |
173 | |
174 | table = cpufreq_frequency_get_table(cpu); | |
175 | if (unlikely(!table)) | |
176 | return 0; | |
177 | ||
b8c67448 | 178 | /* stats already initialized */ |
a9aaf291 | 179 | if (policy->stats) |
b8c67448 VK |
180 | return -EEXIST; |
181 | ||
d5b73cd8 | 182 | stat = kzalloc(sizeof(*stat), GFP_KERNEL); |
0a829c5a | 183 | if ((stat) == NULL) |
1da177e4 | 184 | return -ENOMEM; |
1da177e4 | 185 | |
b24a5b65 | 186 | ret = sysfs_create_group(&policy->kobj, &stats_attr_group); |
0a829c5a | 187 | if (ret) |
1da177e4 LT |
188 | goto error_out; |
189 | ||
190 | stat->cpu = cpu; | |
a9aaf291 | 191 | policy->stats = stat; |
1da177e4 | 192 | |
041526f9 | 193 | cpufreq_for_each_valid_entry(pos, table) |
1da177e4 | 194 | count++; |
1da177e4 | 195 | |
1e7586a1 | 196 | alloc_size = count * sizeof(int) + count * sizeof(u64); |
1da177e4 LT |
197 | |
198 | #ifdef CONFIG_CPU_FREQ_STAT_DETAILS | |
199 | alloc_size += count * count * sizeof(int); | |
200 | #endif | |
201 | stat->max_state = count; | |
e98df50c | 202 | stat->time_in_state = kzalloc(alloc_size, GFP_KERNEL); |
1da177e4 LT |
203 | if (!stat->time_in_state) { |
204 | ret = -ENOMEM; | |
0b7528d9 | 205 | goto error_alloc; |
1da177e4 | 206 | } |
1da177e4 LT |
207 | stat->freq_table = (unsigned int *)(stat->time_in_state + count); |
208 | ||
209 | #ifdef CONFIG_CPU_FREQ_STAT_DETAILS | |
210 | stat->trans_table = stat->freq_table + count; | |
211 | #endif | |
041526f9 SK |
212 | i = 0; |
213 | cpufreq_for_each_valid_entry(pos, table) | |
214 | if (freq_table_get_index(stat, pos->frequency) == -1) | |
215 | stat->freq_table[i++] = pos->frequency; | |
216 | stat->state_num = i; | |
1da177e4 | 217 | spin_lock(&cpufreq_stats_lock); |
58f1df25 | 218 | stat->last_time = get_jiffies_64(); |
1da177e4 LT |
219 | stat->last_index = freq_table_get_index(stat, policy->cur); |
220 | spin_unlock(&cpufreq_stats_lock); | |
1da177e4 | 221 | return 0; |
0b7528d9 SK |
222 | error_alloc: |
223 | sysfs_remove_group(&policy->kobj, &stats_attr_group); | |
1da177e4 | 224 | error_out: |
1da177e4 | 225 | kfree(stat); |
a9aaf291 | 226 | policy->stats = NULL; |
1da177e4 LT |
227 | return ret; |
228 | } | |
229 | ||
b3f9ff88 VK |
230 | static void cpufreq_stats_create_table(unsigned int cpu) |
231 | { | |
232 | struct cpufreq_policy *policy; | |
b3f9ff88 VK |
233 | |
234 | /* | |
235 | * "likely(!policy)" because normally cpufreq_stats will be registered | |
236 | * before cpufreq driver | |
237 | */ | |
238 | policy = cpufreq_cpu_get(cpu); | |
239 | if (likely(!policy)) | |
240 | return; | |
241 | ||
ad4c2302 | 242 | __cpufreq_stats_create_table(policy); |
b3f9ff88 VK |
243 | |
244 | cpufreq_cpu_put(policy); | |
245 | } | |
246 | ||
b8eed8af VK |
247 | static void cpufreq_stats_update_policy_cpu(struct cpufreq_policy *policy) |
248 | { | |
a9aaf291 | 249 | policy->stats->cpu = policy->cpu; |
b8eed8af VK |
250 | } |
251 | ||
0a829c5a DJ |
252 | static int cpufreq_stat_notifier_policy(struct notifier_block *nb, |
253 | unsigned long val, void *data) | |
1da177e4 | 254 | { |
fcd7af91 | 255 | int ret = 0; |
1da177e4 | 256 | struct cpufreq_policy *policy = data; |
b8eed8af VK |
257 | |
258 | if (val == CPUFREQ_UPDATE_POLICY_CPU) { | |
259 | cpufreq_stats_update_policy_cpu(policy); | |
260 | return 0; | |
261 | } | |
262 | ||
fcd7af91 | 263 | if (val == CPUFREQ_CREATE_POLICY) |
ad4c2302 | 264 | ret = __cpufreq_stats_create_table(policy); |
2d13594d VK |
265 | else if (val == CPUFREQ_REMOVE_POLICY) |
266 | __cpufreq_stats_free_table(policy); | |
fcd7af91 VK |
267 | |
268 | return ret; | |
1da177e4 LT |
269 | } |
270 | ||
0a829c5a DJ |
271 | static int cpufreq_stat_notifier_trans(struct notifier_block *nb, |
272 | unsigned long val, void *data) | |
1da177e4 LT |
273 | { |
274 | struct cpufreq_freqs *freq = data; | |
a9aaf291 | 275 | struct cpufreq_policy *policy = cpufreq_cpu_get(freq->cpu); |
1da177e4 LT |
276 | struct cpufreq_stats *stat; |
277 | int old_index, new_index; | |
278 | ||
a9aaf291 VK |
279 | if (!policy) { |
280 | pr_err("%s: No policy found\n", __func__); | |
1da177e4 | 281 | return 0; |
a9aaf291 | 282 | } |
1da177e4 | 283 | |
a9aaf291 VK |
284 | if (val != CPUFREQ_POSTCHANGE) |
285 | goto put_policy; | |
286 | ||
287 | if (!policy->stats) { | |
288 | pr_debug("%s: No stats found\n", __func__); | |
289 | goto put_policy; | |
290 | } | |
291 | ||
292 | stat = policy->stats; | |
8edc59d9 | 293 | |
6501faf8 | 294 | old_index = stat->last_index; |
1da177e4 LT |
295 | new_index = freq_table_get_index(stat, freq->new); |
296 | ||
46a310b8 KRW |
297 | /* We can't do stat->time_in_state[-1]= .. */ |
298 | if (old_index == -1 || new_index == -1) | |
a9aaf291 | 299 | goto put_policy; |
1da177e4 | 300 | |
2aba0c1b | 301 | cpufreq_stats_update(stat); |
46a310b8 KRW |
302 | |
303 | if (old_index == new_index) | |
a9aaf291 | 304 | goto put_policy; |
8edc59d9 | 305 | |
1da177e4 LT |
306 | spin_lock(&cpufreq_stats_lock); |
307 | stat->last_index = new_index; | |
308 | #ifdef CONFIG_CPU_FREQ_STAT_DETAILS | |
309 | stat->trans_table[old_index * stat->max_state + new_index]++; | |
310 | #endif | |
311 | stat->total_trans++; | |
312 | spin_unlock(&cpufreq_stats_lock); | |
a9aaf291 VK |
313 | |
314 | put_policy: | |
315 | cpufreq_cpu_put(policy); | |
1da177e4 LT |
316 | return 0; |
317 | } | |
318 | ||
319 | static struct notifier_block notifier_policy_block = { | |
320 | .notifier_call = cpufreq_stat_notifier_policy | |
321 | }; | |
322 | ||
323 | static struct notifier_block notifier_trans_block = { | |
324 | .notifier_call = cpufreq_stat_notifier_trans | |
325 | }; | |
326 | ||
0a829c5a | 327 | static int __init cpufreq_stats_init(void) |
1da177e4 LT |
328 | { |
329 | int ret; | |
330 | unsigned int cpu; | |
c32b6b8e | 331 | |
1da177e4 | 332 | spin_lock_init(&cpufreq_stats_lock); |
0a829c5a DJ |
333 | ret = cpufreq_register_notifier(¬ifier_policy_block, |
334 | CPUFREQ_POLICY_NOTIFIER); | |
335 | if (ret) | |
1da177e4 LT |
336 | return ret; |
337 | ||
b3f9ff88 VK |
338 | for_each_online_cpu(cpu) |
339 | cpufreq_stats_create_table(cpu); | |
340 | ||
0a829c5a DJ |
341 | ret = cpufreq_register_notifier(¬ifier_trans_block, |
342 | CPUFREQ_TRANSITION_NOTIFIER); | |
343 | if (ret) { | |
1da177e4 LT |
344 | cpufreq_unregister_notifier(¬ifier_policy_block, |
345 | CPUFREQ_POLICY_NOTIFIER); | |
56836fb4 KK |
346 | for_each_online_cpu(cpu) |
347 | cpufreq_stats_free_table(cpu); | |
1da177e4 LT |
348 | return ret; |
349 | } | |
350 | ||
1da177e4 LT |
351 | return 0; |
352 | } | |
0a829c5a | 353 | static void __exit cpufreq_stats_exit(void) |
1da177e4 LT |
354 | { |
355 | unsigned int cpu; | |
c32b6b8e | 356 | |
1da177e4 LT |
357 | cpufreq_unregister_notifier(¬ifier_policy_block, |
358 | CPUFREQ_POLICY_NOTIFIER); | |
359 | cpufreq_unregister_notifier(¬ifier_trans_block, | |
360 | CPUFREQ_TRANSITION_NOTIFIER); | |
2d13594d | 361 | for_each_online_cpu(cpu) |
55395ae7 | 362 | cpufreq_stats_free_table(cpu); |
1da177e4 LT |
363 | } |
364 | ||
0a829c5a | 365 | MODULE_AUTHOR("Zou Nan hai <nanhai.zou@intel.com>"); |
00d0b294 | 366 | MODULE_DESCRIPTION("Export cpufreq stats via sysfs"); |
0a829c5a | 367 | MODULE_LICENSE("GPL"); |
1da177e4 LT |
368 | |
369 | module_init(cpufreq_stats_init); | |
370 | module_exit(cpufreq_stats_exit); |