Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * drivers/cpufreq/cpufreq_stats.c | |
3 | * | |
4 | * Copyright (C) 2003-2004 Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>. | |
5 | * (C) 2004 Zou Nan hai <nanhai.zou@intel.com>. | |
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 | ||
12 | #include <linux/config.h> | |
13 | #include <linux/kernel.h> | |
14 | #include <linux/sysdev.h> | |
15 | #include <linux/cpu.h> | |
16 | #include <linux/sysfs.h> | |
17 | #include <linux/cpufreq.h> | |
18 | #include <linux/jiffies.h> | |
19 | #include <linux/percpu.h> | |
20 | #include <linux/kobject.h> | |
21 | #include <linux/spinlock.h> | |
22 | ||
23 | static spinlock_t cpufreq_stats_lock; | |
24 | ||
25 | #define CPUFREQ_STATDEVICE_ATTR(_name,_mode,_show) \ | |
26 | static struct freq_attr _attr_##_name = {\ | |
27 | .attr = {.name = __stringify(_name), .owner = THIS_MODULE, \ | |
28 | .mode = _mode, }, \ | |
29 | .show = _show,\ | |
30 | }; | |
31 | ||
32 | static unsigned long | |
33 | delta_time(unsigned long old, unsigned long new) | |
34 | { | |
35 | return (old > new) ? (old - new): (new + ~old + 1); | |
36 | } | |
37 | ||
38 | struct cpufreq_stats { | |
39 | unsigned int cpu; | |
40 | unsigned int total_trans; | |
41 | unsigned long long last_time; | |
42 | unsigned int max_state; | |
43 | unsigned int state_num; | |
44 | unsigned int last_index; | |
45 | unsigned long long *time_in_state; | |
46 | unsigned int *freq_table; | |
47 | #ifdef CONFIG_CPU_FREQ_STAT_DETAILS | |
48 | unsigned int *trans_table; | |
49 | #endif | |
50 | }; | |
51 | ||
52 | static struct cpufreq_stats *cpufreq_stats_table[NR_CPUS]; | |
53 | ||
54 | struct cpufreq_stats_attribute { | |
55 | struct attribute attr; | |
56 | ssize_t(*show) (struct cpufreq_stats *, char *); | |
57 | }; | |
58 | ||
59 | static int | |
60 | cpufreq_stats_update (unsigned int cpu) | |
61 | { | |
62 | struct cpufreq_stats *stat; | |
63 | spin_lock(&cpufreq_stats_lock); | |
64 | stat = cpufreq_stats_table[cpu]; | |
65 | if (stat->time_in_state) | |
66 | stat->time_in_state[stat->last_index] += | |
67 | delta_time(stat->last_time, jiffies); | |
68 | stat->last_time = jiffies; | |
69 | spin_unlock(&cpufreq_stats_lock); | |
70 | return 0; | |
71 | } | |
72 | ||
73 | static ssize_t | |
74 | show_total_trans(struct cpufreq_policy *policy, char *buf) | |
75 | { | |
76 | struct cpufreq_stats *stat = cpufreq_stats_table[policy->cpu]; | |
77 | if(!stat) | |
78 | return 0; | |
79 | return sprintf(buf, "%d\n", | |
80 | cpufreq_stats_table[stat->cpu]->total_trans); | |
81 | } | |
82 | ||
83 | static ssize_t | |
84 | show_time_in_state(struct cpufreq_policy *policy, char *buf) | |
85 | { | |
86 | ssize_t len = 0; | |
87 | int i; | |
88 | struct cpufreq_stats *stat = cpufreq_stats_table[policy->cpu]; | |
89 | if(!stat) | |
90 | return 0; | |
91 | cpufreq_stats_update(stat->cpu); | |
92 | for (i = 0; i < stat->state_num; i++) { | |
93 | len += sprintf(buf + len, "%u %llu\n", | |
94 | stat->freq_table[i], stat->time_in_state[i]); | |
95 | } | |
96 | return len; | |
97 | } | |
98 | ||
99 | #ifdef CONFIG_CPU_FREQ_STAT_DETAILS | |
100 | static ssize_t | |
101 | show_trans_table(struct cpufreq_policy *policy, char *buf) | |
102 | { | |
103 | ssize_t len = 0; | |
104 | int i, j; | |
105 | ||
106 | struct cpufreq_stats *stat = cpufreq_stats_table[policy->cpu]; | |
107 | if(!stat) | |
108 | return 0; | |
109 | cpufreq_stats_update(stat->cpu); | |
110 | for (i = 0; i < stat->state_num; i++) { | |
111 | if (len >= PAGE_SIZE) | |
112 | break; | |
113 | len += snprintf(buf + len, PAGE_SIZE - len, "%9u:\t", | |
114 | stat->freq_table[i]); | |
115 | ||
116 | for (j = 0; j < stat->state_num; j++) { | |
117 | if (len >= PAGE_SIZE) | |
118 | break; | |
119 | len += snprintf(buf + len, PAGE_SIZE - len, "%u\t", | |
120 | stat->trans_table[i*stat->max_state+j]); | |
121 | } | |
122 | len += snprintf(buf + len, PAGE_SIZE - len, "\n"); | |
123 | } | |
124 | return len; | |
125 | } | |
126 | CPUFREQ_STATDEVICE_ATTR(trans_table,0444,show_trans_table); | |
127 | #endif | |
128 | ||
129 | CPUFREQ_STATDEVICE_ATTR(total_trans,0444,show_total_trans); | |
130 | CPUFREQ_STATDEVICE_ATTR(time_in_state,0444,show_time_in_state); | |
131 | ||
132 | static struct attribute *default_attrs[] = { | |
133 | &_attr_total_trans.attr, | |
134 | &_attr_time_in_state.attr, | |
135 | #ifdef CONFIG_CPU_FREQ_STAT_DETAILS | |
136 | &_attr_trans_table.attr, | |
137 | #endif | |
138 | NULL | |
139 | }; | |
140 | static struct attribute_group stats_attr_group = { | |
141 | .attrs = default_attrs, | |
142 | .name = "stats" | |
143 | }; | |
144 | ||
145 | static int | |
146 | freq_table_get_index(struct cpufreq_stats *stat, unsigned int freq) | |
147 | { | |
148 | int index; | |
149 | for (index = 0; index < stat->max_state; index++) | |
150 | if (stat->freq_table[index] == freq) | |
151 | return index; | |
152 | return -1; | |
153 | } | |
154 | ||
155 | static void | |
156 | cpufreq_stats_free_table (unsigned int cpu) | |
157 | { | |
158 | struct cpufreq_stats *stat = cpufreq_stats_table[cpu]; | |
159 | struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); | |
160 | if (policy && policy->cpu == cpu) | |
161 | sysfs_remove_group(&policy->kobj, &stats_attr_group); | |
162 | if (stat) { | |
163 | kfree(stat->time_in_state); | |
164 | kfree(stat); | |
165 | } | |
166 | cpufreq_stats_table[cpu] = NULL; | |
167 | if (policy) | |
168 | cpufreq_cpu_put(policy); | |
169 | } | |
170 | ||
171 | static int | |
172 | cpufreq_stats_create_table (struct cpufreq_policy *policy, | |
173 | struct cpufreq_frequency_table *table) | |
174 | { | |
175 | unsigned int i, j, count = 0, ret = 0; | |
176 | struct cpufreq_stats *stat; | |
177 | struct cpufreq_policy *data; | |
178 | unsigned int alloc_size; | |
179 | unsigned int cpu = policy->cpu; | |
180 | if (cpufreq_stats_table[cpu]) | |
181 | return -EBUSY; | |
182 | if ((stat = kmalloc(sizeof(struct cpufreq_stats), GFP_KERNEL)) == NULL) | |
183 | return -ENOMEM; | |
184 | memset(stat, 0, sizeof (struct cpufreq_stats)); | |
185 | ||
186 | data = cpufreq_cpu_get(cpu); | |
187 | if ((ret = sysfs_create_group(&data->kobj, &stats_attr_group))) | |
188 | goto error_out; | |
189 | ||
190 | stat->cpu = cpu; | |
191 | cpufreq_stats_table[cpu] = stat; | |
192 | ||
193 | for (i=0; table[i].frequency != CPUFREQ_TABLE_END; i++) { | |
194 | unsigned int freq = table[i].frequency; | |
195 | if (freq == CPUFREQ_ENTRY_INVALID) | |
196 | continue; | |
197 | count++; | |
198 | } | |
199 | ||
200 | alloc_size = count * sizeof(int) + count * sizeof(long long); | |
201 | ||
202 | #ifdef CONFIG_CPU_FREQ_STAT_DETAILS | |
203 | alloc_size += count * count * sizeof(int); | |
204 | #endif | |
205 | stat->max_state = count; | |
206 | stat->time_in_state = kmalloc(alloc_size, GFP_KERNEL); | |
207 | if (!stat->time_in_state) { | |
208 | ret = -ENOMEM; | |
209 | goto error_out; | |
210 | } | |
211 | memset(stat->time_in_state, 0, alloc_size); | |
212 | stat->freq_table = (unsigned int *)(stat->time_in_state + count); | |
213 | ||
214 | #ifdef CONFIG_CPU_FREQ_STAT_DETAILS | |
215 | stat->trans_table = stat->freq_table + count; | |
216 | #endif | |
217 | j = 0; | |
218 | for (i = 0; table[i].frequency != CPUFREQ_TABLE_END; i++) { | |
219 | unsigned int freq = table[i].frequency; | |
220 | if (freq == CPUFREQ_ENTRY_INVALID) | |
221 | continue; | |
222 | if (freq_table_get_index(stat, freq) == -1) | |
223 | stat->freq_table[j++] = freq; | |
224 | } | |
225 | stat->state_num = j; | |
226 | spin_lock(&cpufreq_stats_lock); | |
227 | stat->last_time = jiffies; | |
228 | stat->last_index = freq_table_get_index(stat, policy->cur); | |
229 | spin_unlock(&cpufreq_stats_lock); | |
230 | cpufreq_cpu_put(data); | |
231 | return 0; | |
232 | error_out: | |
233 | cpufreq_cpu_put(data); | |
234 | kfree(stat); | |
235 | cpufreq_stats_table[cpu] = NULL; | |
236 | return ret; | |
237 | } | |
238 | ||
239 | static int | |
240 | cpufreq_stat_notifier_policy (struct notifier_block *nb, unsigned long val, | |
241 | void *data) | |
242 | { | |
243 | int ret; | |
244 | struct cpufreq_policy *policy = data; | |
245 | struct cpufreq_frequency_table *table; | |
246 | unsigned int cpu = policy->cpu; | |
247 | if (val != CPUFREQ_NOTIFY) | |
248 | return 0; | |
249 | table = cpufreq_frequency_get_table(cpu); | |
250 | if (!table) | |
251 | return 0; | |
252 | if ((ret = cpufreq_stats_create_table(policy, table))) | |
253 | return ret; | |
254 | return 0; | |
255 | } | |
256 | ||
257 | static int | |
258 | cpufreq_stat_notifier_trans (struct notifier_block *nb, unsigned long val, | |
259 | void *data) | |
260 | { | |
261 | struct cpufreq_freqs *freq = data; | |
262 | struct cpufreq_stats *stat; | |
263 | int old_index, new_index; | |
264 | ||
265 | if (val != CPUFREQ_POSTCHANGE) | |
266 | return 0; | |
267 | ||
268 | stat = cpufreq_stats_table[freq->cpu]; | |
269 | if (!stat) | |
270 | return 0; | |
271 | old_index = freq_table_get_index(stat, freq->old); | |
272 | new_index = freq_table_get_index(stat, freq->new); | |
273 | ||
274 | cpufreq_stats_update(freq->cpu); | |
275 | if (old_index == new_index) | |
276 | return 0; | |
277 | ||
278 | spin_lock(&cpufreq_stats_lock); | |
279 | stat->last_index = new_index; | |
280 | #ifdef CONFIG_CPU_FREQ_STAT_DETAILS | |
281 | stat->trans_table[old_index * stat->max_state + new_index]++; | |
282 | #endif | |
283 | stat->total_trans++; | |
284 | spin_unlock(&cpufreq_stats_lock); | |
285 | return 0; | |
286 | } | |
287 | ||
288 | static struct notifier_block notifier_policy_block = { | |
289 | .notifier_call = cpufreq_stat_notifier_policy | |
290 | }; | |
291 | ||
292 | static struct notifier_block notifier_trans_block = { | |
293 | .notifier_call = cpufreq_stat_notifier_trans | |
294 | }; | |
295 | ||
296 | static int | |
297 | __init cpufreq_stats_init(void) | |
298 | { | |
299 | int ret; | |
300 | unsigned int cpu; | |
301 | spin_lock_init(&cpufreq_stats_lock); | |
302 | if ((ret = cpufreq_register_notifier(¬ifier_policy_block, | |
303 | CPUFREQ_POLICY_NOTIFIER))) | |
304 | return ret; | |
305 | ||
306 | if ((ret = cpufreq_register_notifier(¬ifier_trans_block, | |
307 | CPUFREQ_TRANSITION_NOTIFIER))) { | |
308 | cpufreq_unregister_notifier(¬ifier_policy_block, | |
309 | CPUFREQ_POLICY_NOTIFIER); | |
310 | return ret; | |
311 | } | |
312 | ||
313 | for_each_cpu(cpu) | |
314 | cpufreq_update_policy(cpu); | |
315 | return 0; | |
316 | } | |
317 | static void | |
318 | __exit cpufreq_stats_exit(void) | |
319 | { | |
320 | unsigned int cpu; | |
321 | cpufreq_unregister_notifier(¬ifier_policy_block, | |
322 | CPUFREQ_POLICY_NOTIFIER); | |
323 | cpufreq_unregister_notifier(¬ifier_trans_block, | |
324 | CPUFREQ_TRANSITION_NOTIFIER); | |
325 | for_each_cpu(cpu) | |
326 | cpufreq_stats_free_table(cpu); | |
327 | } | |
328 | ||
329 | MODULE_AUTHOR ("Zou Nan hai <nanhai.zou@intel.com>"); | |
330 | MODULE_DESCRIPTION ("'cpufreq_stats' - A driver to export cpufreq stats through sysfs filesystem"); | |
331 | MODULE_LICENSE ("GPL"); | |
332 | ||
333 | module_init(cpufreq_stats_init); | |
334 | module_exit(cpufreq_stats_exit); |