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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 18:20:36 -0400
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 18:20:36 -0400
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /drivers/cpufreq/cpufreq_stats.c
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'drivers/cpufreq/cpufreq_stats.c')
-rw-r--r--drivers/cpufreq/cpufreq_stats.c334
1 files changed, 334 insertions, 0 deletions
diff --git a/drivers/cpufreq/cpufreq_stats.c b/drivers/cpufreq/cpufreq_stats.c
new file mode 100644
index 000000000000..2084593937c6
--- /dev/null
+++ b/drivers/cpufreq/cpufreq_stats.c
@@ -0,0 +1,334 @@
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
23static spinlock_t cpufreq_stats_lock;
24
25#define CPUFREQ_STATDEVICE_ATTR(_name,_mode,_show) \
26static struct freq_attr _attr_##_name = {\
27 .attr = {.name = __stringify(_name), .owner = THIS_MODULE, \
28 .mode = _mode, }, \
29 .show = _show,\
30};
31
32static unsigned long
33delta_time(unsigned long old, unsigned long new)
34{
35 return (old > new) ? (old - new): (new + ~old + 1);
36}
37
38struct 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
52static struct cpufreq_stats *cpufreq_stats_table[NR_CPUS];
53
54struct cpufreq_stats_attribute {
55 struct attribute attr;
56 ssize_t(*show) (struct cpufreq_stats *, char *);
57};
58
59static int
60cpufreq_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
73static ssize_t
74show_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
83static ssize_t
84show_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
100static ssize_t
101show_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}
126CPUFREQ_STATDEVICE_ATTR(trans_table,0444,show_trans_table);
127#endif
128
129CPUFREQ_STATDEVICE_ATTR(total_trans,0444,show_total_trans);
130CPUFREQ_STATDEVICE_ATTR(time_in_state,0444,show_time_in_state);
131
132static 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};
140static struct attribute_group stats_attr_group = {
141 .attrs = default_attrs,
142 .name = "stats"
143};
144
145static int
146freq_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
155static void
156cpufreq_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
171static int
172cpufreq_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;
232error_out:
233 cpufreq_cpu_put(data);
234 kfree(stat);
235 cpufreq_stats_table[cpu] = NULL;
236 return ret;
237}
238
239static int
240cpufreq_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
257static int
258cpufreq_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
288static struct notifier_block notifier_policy_block = {
289 .notifier_call = cpufreq_stat_notifier_policy
290};
291
292static struct notifier_block notifier_trans_block = {
293 .notifier_call = cpufreq_stat_notifier_trans
294};
295
296static 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(&notifier_policy_block,
303 CPUFREQ_POLICY_NOTIFIER)))
304 return ret;
305
306 if ((ret = cpufreq_register_notifier(&notifier_trans_block,
307 CPUFREQ_TRANSITION_NOTIFIER))) {
308 cpufreq_unregister_notifier(&notifier_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}
317static void
318__exit cpufreq_stats_exit(void)
319{
320 unsigned int cpu;
321 cpufreq_unregister_notifier(&notifier_policy_block,
322 CPUFREQ_POLICY_NOTIFIER);
323 cpufreq_unregister_notifier(&notifier_trans_block,
324 CPUFREQ_TRANSITION_NOTIFIER);
325 for_each_cpu(cpu)
326 cpufreq_stats_free_table(cpu);
327}
328
329MODULE_AUTHOR ("Zou Nan hai <nanhai.zou@intel.com>");
330MODULE_DESCRIPTION ("'cpufreq_stats' - A driver to export cpufreq stats through sysfs filesystem");
331MODULE_LICENSE ("GPL");
332
333module_init(cpufreq_stats_init);
334module_exit(cpufreq_stats_exit);