2 * drivers/cpufreq/cpufreq_stats.c
4 * Copyright (C) 2003-2004 Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>.
5 * (C) 2004 Zou Nan hai <nanhai.zou@intel.com>.
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.
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 #include <linux/notifier.h>
23 #include <asm/cputime.h>
25 static spinlock_t cpufreq_stats_lock
;
27 #define CPUFREQ_STATDEVICE_ATTR(_name,_mode,_show) \
28 static struct freq_attr _attr_##_name = {\
29 .attr = {.name = __stringify(_name), .owner = THIS_MODULE, \
34 struct cpufreq_stats
{
36 unsigned int total_trans
;
37 unsigned long long last_time
;
38 unsigned int max_state
;
39 unsigned int state_num
;
40 unsigned int last_index
;
41 cputime64_t
*time_in_state
;
42 unsigned int *freq_table
;
43 #ifdef CONFIG_CPU_FREQ_STAT_DETAILS
44 unsigned int *trans_table
;
48 static struct cpufreq_stats
*cpufreq_stats_table
[NR_CPUS
];
50 struct cpufreq_stats_attribute
{
51 struct attribute attr
;
52 ssize_t(*show
) (struct cpufreq_stats
*, char *);
56 cpufreq_stats_update (unsigned int cpu
)
58 struct cpufreq_stats
*stat
;
59 unsigned long long cur_time
;
61 cur_time
= get_jiffies_64();
62 spin_lock(&cpufreq_stats_lock
);
63 stat
= cpufreq_stats_table
[cpu
];
64 if (stat
->time_in_state
)
65 stat
->time_in_state
[stat
->last_index
] =
66 cputime64_add(stat
->time_in_state
[stat
->last_index
],
67 cputime_sub(cur_time
, stat
->last_time
));
68 stat
->last_time
= cur_time
;
69 spin_unlock(&cpufreq_stats_lock
);
74 show_total_trans(struct cpufreq_policy
*policy
, char *buf
)
76 struct cpufreq_stats
*stat
= cpufreq_stats_table
[policy
->cpu
];
79 return sprintf(buf
, "%d\n",
80 cpufreq_stats_table
[stat
->cpu
]->total_trans
);
84 show_time_in_state(struct cpufreq_policy
*policy
, char *buf
)
88 struct cpufreq_stats
*stat
= cpufreq_stats_table
[policy
->cpu
];
91 cpufreq_stats_update(stat
->cpu
);
92 for (i
= 0; i
< stat
->state_num
; i
++) {
93 len
+= sprintf(buf
+ len
, "%u %llu\n", stat
->freq_table
[i
],
94 (unsigned long long)cputime64_to_clock_t(stat
->time_in_state
[i
]));
99 #ifdef CONFIG_CPU_FREQ_STAT_DETAILS
101 show_trans_table(struct cpufreq_policy
*policy
, char *buf
)
106 struct cpufreq_stats
*stat
= cpufreq_stats_table
[policy
->cpu
];
109 cpufreq_stats_update(stat
->cpu
);
110 len
+= snprintf(buf
+ len
, PAGE_SIZE
- len
, " From : To\n");
111 len
+= snprintf(buf
+ len
, PAGE_SIZE
- len
, " : ");
112 for (i
= 0; i
< stat
->state_num
; i
++) {
113 if (len
>= PAGE_SIZE
)
115 len
+= snprintf(buf
+ len
, PAGE_SIZE
- len
, "%9u ",
116 stat
->freq_table
[i
]);
118 if (len
>= PAGE_SIZE
)
121 len
+= snprintf(buf
+ len
, PAGE_SIZE
- len
, "\n");
123 for (i
= 0; i
< stat
->state_num
; i
++) {
124 if (len
>= PAGE_SIZE
)
127 len
+= snprintf(buf
+ len
, PAGE_SIZE
- len
, "%9u: ",
128 stat
->freq_table
[i
]);
130 for (j
= 0; j
< stat
->state_num
; j
++) {
131 if (len
>= PAGE_SIZE
)
133 len
+= snprintf(buf
+ len
, PAGE_SIZE
- len
, "%9u ",
134 stat
->trans_table
[i
*stat
->max_state
+j
]);
136 len
+= snprintf(buf
+ len
, PAGE_SIZE
- len
, "\n");
140 CPUFREQ_STATDEVICE_ATTR(trans_table
,0444,show_trans_table
);
143 CPUFREQ_STATDEVICE_ATTR(total_trans
,0444,show_total_trans
);
144 CPUFREQ_STATDEVICE_ATTR(time_in_state
,0444,show_time_in_state
);
146 static struct attribute
*default_attrs
[] = {
147 &_attr_total_trans
.attr
,
148 &_attr_time_in_state
.attr
,
149 #ifdef CONFIG_CPU_FREQ_STAT_DETAILS
150 &_attr_trans_table
.attr
,
154 static struct attribute_group stats_attr_group
= {
155 .attrs
= default_attrs
,
160 freq_table_get_index(struct cpufreq_stats
*stat
, unsigned int freq
)
163 for (index
= 0; index
< stat
->max_state
; index
++)
164 if (stat
->freq_table
[index
] == freq
)
170 cpufreq_stats_free_table (unsigned int cpu
)
172 struct cpufreq_stats
*stat
= cpufreq_stats_table
[cpu
];
173 struct cpufreq_policy
*policy
= cpufreq_cpu_get(cpu
);
174 if (policy
&& policy
->cpu
== cpu
)
175 sysfs_remove_group(&policy
->kobj
, &stats_attr_group
);
177 kfree(stat
->time_in_state
);
180 cpufreq_stats_table
[cpu
] = NULL
;
182 cpufreq_cpu_put(policy
);
186 cpufreq_stats_create_table (struct cpufreq_policy
*policy
,
187 struct cpufreq_frequency_table
*table
)
189 unsigned int i
, j
, count
= 0, ret
= 0;
190 struct cpufreq_stats
*stat
;
191 struct cpufreq_policy
*data
;
192 unsigned int alloc_size
;
193 unsigned int cpu
= policy
->cpu
;
194 if (cpufreq_stats_table
[cpu
])
196 if ((stat
= kmalloc(sizeof(struct cpufreq_stats
), GFP_KERNEL
)) == NULL
)
198 memset(stat
, 0, sizeof (struct cpufreq_stats
));
200 data
= cpufreq_cpu_get(cpu
);
201 if ((ret
= sysfs_create_group(&data
->kobj
, &stats_attr_group
)))
205 cpufreq_stats_table
[cpu
] = stat
;
207 for (i
=0; table
[i
].frequency
!= CPUFREQ_TABLE_END
; i
++) {
208 unsigned int freq
= table
[i
].frequency
;
209 if (freq
== CPUFREQ_ENTRY_INVALID
)
214 alloc_size
= count
* sizeof(int) + count
* sizeof(cputime64_t
);
216 #ifdef CONFIG_CPU_FREQ_STAT_DETAILS
217 alloc_size
+= count
* count
* sizeof(int);
219 stat
->max_state
= count
;
220 stat
->time_in_state
= kmalloc(alloc_size
, GFP_KERNEL
);
221 if (!stat
->time_in_state
) {
225 memset(stat
->time_in_state
, 0, alloc_size
);
226 stat
->freq_table
= (unsigned int *)(stat
->time_in_state
+ count
);
228 #ifdef CONFIG_CPU_FREQ_STAT_DETAILS
229 stat
->trans_table
= stat
->freq_table
+ count
;
232 for (i
= 0; table
[i
].frequency
!= CPUFREQ_TABLE_END
; i
++) {
233 unsigned int freq
= table
[i
].frequency
;
234 if (freq
== CPUFREQ_ENTRY_INVALID
)
236 if (freq_table_get_index(stat
, freq
) == -1)
237 stat
->freq_table
[j
++] = freq
;
240 spin_lock(&cpufreq_stats_lock
);
241 stat
->last_time
= get_jiffies_64();
242 stat
->last_index
= freq_table_get_index(stat
, policy
->cur
);
243 spin_unlock(&cpufreq_stats_lock
);
244 cpufreq_cpu_put(data
);
247 cpufreq_cpu_put(data
);
249 cpufreq_stats_table
[cpu
] = NULL
;
254 cpufreq_stat_notifier_policy (struct notifier_block
*nb
, unsigned long val
,
258 struct cpufreq_policy
*policy
= data
;
259 struct cpufreq_frequency_table
*table
;
260 unsigned int cpu
= policy
->cpu
;
261 if (val
!= CPUFREQ_NOTIFY
)
263 table
= cpufreq_frequency_get_table(cpu
);
266 if ((ret
= cpufreq_stats_create_table(policy
, table
)))
272 cpufreq_stat_notifier_trans (struct notifier_block
*nb
, unsigned long val
,
275 struct cpufreq_freqs
*freq
= data
;
276 struct cpufreq_stats
*stat
;
277 int old_index
, new_index
;
279 if (val
!= CPUFREQ_POSTCHANGE
)
282 stat
= cpufreq_stats_table
[freq
->cpu
];
285 old_index
= freq_table_get_index(stat
, freq
->old
);
286 new_index
= freq_table_get_index(stat
, freq
->new);
288 cpufreq_stats_update(freq
->cpu
);
289 if (old_index
== new_index
)
292 spin_lock(&cpufreq_stats_lock
);
293 stat
->last_index
= new_index
;
294 #ifdef CONFIG_CPU_FREQ_STAT_DETAILS
295 stat
->trans_table
[old_index
* stat
->max_state
+ new_index
]++;
298 spin_unlock(&cpufreq_stats_lock
);
302 static int __cpuinit
cpufreq_stat_cpu_callback(struct notifier_block
*nfb
,
303 unsigned long action
, void *hcpu
)
305 unsigned int cpu
= (unsigned long)hcpu
;
309 cpufreq_update_policy(cpu
);
312 cpufreq_stats_free_table(cpu
);
318 static struct notifier_block cpufreq_stat_cpu_notifier
=
320 .notifier_call
= cpufreq_stat_cpu_callback
,
323 static struct notifier_block notifier_policy_block
= {
324 .notifier_call
= cpufreq_stat_notifier_policy
327 static struct notifier_block notifier_trans_block
= {
328 .notifier_call
= cpufreq_stat_notifier_trans
332 __init
cpufreq_stats_init(void)
337 spin_lock_init(&cpufreq_stats_lock
);
338 if ((ret
= cpufreq_register_notifier(¬ifier_policy_block
,
339 CPUFREQ_POLICY_NOTIFIER
)))
342 if ((ret
= cpufreq_register_notifier(¬ifier_trans_block
,
343 CPUFREQ_TRANSITION_NOTIFIER
))) {
344 cpufreq_unregister_notifier(¬ifier_policy_block
,
345 CPUFREQ_POLICY_NOTIFIER
);
349 register_cpu_notifier(&cpufreq_stat_cpu_notifier
);
351 for_each_online_cpu(cpu
) {
352 cpufreq_stat_cpu_callback(&cpufreq_stat_cpu_notifier
, CPU_ONLINE
,
355 unlock_cpu_hotplug();
359 __exit
cpufreq_stats_exit(void)
363 cpufreq_unregister_notifier(¬ifier_policy_block
,
364 CPUFREQ_POLICY_NOTIFIER
);
365 cpufreq_unregister_notifier(¬ifier_trans_block
,
366 CPUFREQ_TRANSITION_NOTIFIER
);
367 unregister_cpu_notifier(&cpufreq_stat_cpu_notifier
);
369 for_each_online_cpu(cpu
) {
370 cpufreq_stat_cpu_callback(&cpufreq_stat_cpu_notifier
, CPU_DEAD
,
373 unlock_cpu_hotplug();
376 MODULE_AUTHOR ("Zou Nan hai <nanhai.zou@intel.com>");
377 MODULE_DESCRIPTION ("'cpufreq_stats' - A driver to export cpufreq stats through sysfs filesystem");
378 MODULE_LICENSE ("GPL");
380 module_init(cpufreq_stats_init
);
381 module_exit(cpufreq_stats_exit
);