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/kernel.h>
13 #include <linux/sysdev.h>
14 #include <linux/cpu.h>
15 #include <linux/sysfs.h>
16 #include <linux/cpufreq.h>
17 #include <linux/jiffies.h>
18 #include <linux/percpu.h>
19 #include <linux/kobject.h>
20 #include <linux/spinlock.h>
21 #include <linux/notifier.h>
22 #include <asm/cputime.h>
24 static spinlock_t cpufreq_stats_lock
;
26 #define CPUFREQ_STATDEVICE_ATTR(_name,_mode,_show) \
27 static struct freq_attr _attr_##_name = {\
28 .attr = {.name = __stringify(_name), .mode = _mode, }, \
32 struct cpufreq_stats
{
34 unsigned int total_trans
;
35 unsigned long long last_time
;
36 unsigned int max_state
;
37 unsigned int state_num
;
38 unsigned int last_index
;
39 cputime64_t
*time_in_state
;
40 unsigned int *freq_table
;
41 #ifdef CONFIG_CPU_FREQ_STAT_DETAILS
42 unsigned int *trans_table
;
46 static struct cpufreq_stats
*cpufreq_stats_table
[NR_CPUS
];
48 struct cpufreq_stats_attribute
{
49 struct attribute attr
;
50 ssize_t(*show
) (struct cpufreq_stats
*, char *);
54 cpufreq_stats_update (unsigned int cpu
)
56 struct cpufreq_stats
*stat
;
57 unsigned long long cur_time
;
59 cur_time
= get_jiffies_64();
60 spin_lock(&cpufreq_stats_lock
);
61 stat
= cpufreq_stats_table
[cpu
];
62 if (stat
->time_in_state
)
63 stat
->time_in_state
[stat
->last_index
] =
64 cputime64_add(stat
->time_in_state
[stat
->last_index
],
65 cputime_sub(cur_time
, stat
->last_time
));
66 stat
->last_time
= cur_time
;
67 spin_unlock(&cpufreq_stats_lock
);
72 show_total_trans(struct cpufreq_policy
*policy
, char *buf
)
74 struct cpufreq_stats
*stat
= cpufreq_stats_table
[policy
->cpu
];
77 return sprintf(buf
, "%d\n",
78 cpufreq_stats_table
[stat
->cpu
]->total_trans
);
82 show_time_in_state(struct cpufreq_policy
*policy
, char *buf
)
86 struct cpufreq_stats
*stat
= cpufreq_stats_table
[policy
->cpu
];
89 cpufreq_stats_update(stat
->cpu
);
90 for (i
= 0; i
< stat
->state_num
; i
++) {
91 len
+= sprintf(buf
+ len
, "%u %llu\n", stat
->freq_table
[i
],
92 (unsigned long long)cputime64_to_clock_t(stat
->time_in_state
[i
]));
97 #ifdef CONFIG_CPU_FREQ_STAT_DETAILS
99 show_trans_table(struct cpufreq_policy
*policy
, char *buf
)
104 struct cpufreq_stats
*stat
= cpufreq_stats_table
[policy
->cpu
];
107 cpufreq_stats_update(stat
->cpu
);
108 len
+= snprintf(buf
+ len
, PAGE_SIZE
- len
, " From : To\n");
109 len
+= snprintf(buf
+ len
, PAGE_SIZE
- len
, " : ");
110 for (i
= 0; i
< stat
->state_num
; i
++) {
111 if (len
>= PAGE_SIZE
)
113 len
+= snprintf(buf
+ len
, PAGE_SIZE
- len
, "%9u ",
114 stat
->freq_table
[i
]);
116 if (len
>= PAGE_SIZE
)
119 len
+= snprintf(buf
+ len
, PAGE_SIZE
- len
, "\n");
121 for (i
= 0; i
< stat
->state_num
; i
++) {
122 if (len
>= PAGE_SIZE
)
125 len
+= snprintf(buf
+ len
, PAGE_SIZE
- len
, "%9u: ",
126 stat
->freq_table
[i
]);
128 for (j
= 0; j
< stat
->state_num
; j
++) {
129 if (len
>= PAGE_SIZE
)
131 len
+= snprintf(buf
+ len
, PAGE_SIZE
- len
, "%9u ",
132 stat
->trans_table
[i
*stat
->max_state
+j
]);
134 if (len
>= PAGE_SIZE
)
136 len
+= snprintf(buf
+ len
, PAGE_SIZE
- len
, "\n");
138 if (len
>= PAGE_SIZE
)
142 CPUFREQ_STATDEVICE_ATTR(trans_table
,0444,show_trans_table
);
145 CPUFREQ_STATDEVICE_ATTR(total_trans
,0444,show_total_trans
);
146 CPUFREQ_STATDEVICE_ATTR(time_in_state
,0444,show_time_in_state
);
148 static struct attribute
*default_attrs
[] = {
149 &_attr_total_trans
.attr
,
150 &_attr_time_in_state
.attr
,
151 #ifdef CONFIG_CPU_FREQ_STAT_DETAILS
152 &_attr_trans_table
.attr
,
156 static struct attribute_group stats_attr_group
= {
157 .attrs
= default_attrs
,
162 freq_table_get_index(struct cpufreq_stats
*stat
, unsigned int freq
)
165 for (index
= 0; index
< stat
->max_state
; index
++)
166 if (stat
->freq_table
[index
] == freq
)
171 static void cpufreq_stats_free_table(unsigned int cpu
)
173 struct cpufreq_stats
*stat
= cpufreq_stats_table
[cpu
];
174 struct cpufreq_policy
*policy
= cpufreq_cpu_get(cpu
);
175 if (policy
&& policy
->cpu
== cpu
)
176 sysfs_remove_group(&policy
->kobj
, &stats_attr_group
);
178 kfree(stat
->time_in_state
);
181 cpufreq_stats_table
[cpu
] = NULL
;
183 cpufreq_cpu_put(policy
);
187 cpufreq_stats_create_table (struct cpufreq_policy
*policy
,
188 struct cpufreq_frequency_table
*table
)
190 unsigned int i
, j
, count
= 0, ret
= 0;
191 struct cpufreq_stats
*stat
;
192 struct cpufreq_policy
*data
;
193 unsigned int alloc_size
;
194 unsigned int cpu
= policy
->cpu
;
195 if (cpufreq_stats_table
[cpu
])
197 if ((stat
= kzalloc(sizeof(struct cpufreq_stats
), GFP_KERNEL
)) == NULL
)
200 data
= cpufreq_cpu_get(cpu
);
206 if ((ret
= sysfs_create_group(&data
->kobj
, &stats_attr_group
)))
210 cpufreq_stats_table
[cpu
] = stat
;
212 for (i
=0; table
[i
].frequency
!= CPUFREQ_TABLE_END
; i
++) {
213 unsigned int freq
= table
[i
].frequency
;
214 if (freq
== CPUFREQ_ENTRY_INVALID
)
219 alloc_size
= count
* sizeof(int) + count
* sizeof(cputime64_t
);
221 #ifdef CONFIG_CPU_FREQ_STAT_DETAILS
222 alloc_size
+= count
* count
* sizeof(int);
224 stat
->max_state
= count
;
225 stat
->time_in_state
= kzalloc(alloc_size
, GFP_KERNEL
);
226 if (!stat
->time_in_state
) {
230 stat
->freq_table
= (unsigned int *)(stat
->time_in_state
+ count
);
232 #ifdef CONFIG_CPU_FREQ_STAT_DETAILS
233 stat
->trans_table
= stat
->freq_table
+ count
;
236 for (i
= 0; table
[i
].frequency
!= CPUFREQ_TABLE_END
; i
++) {
237 unsigned int freq
= table
[i
].frequency
;
238 if (freq
== CPUFREQ_ENTRY_INVALID
)
240 if (freq_table_get_index(stat
, freq
) == -1)
241 stat
->freq_table
[j
++] = freq
;
244 spin_lock(&cpufreq_stats_lock
);
245 stat
->last_time
= get_jiffies_64();
246 stat
->last_index
= freq_table_get_index(stat
, policy
->cur
);
247 spin_unlock(&cpufreq_stats_lock
);
248 cpufreq_cpu_put(data
);
251 cpufreq_cpu_put(data
);
254 cpufreq_stats_table
[cpu
] = NULL
;
259 cpufreq_stat_notifier_policy (struct notifier_block
*nb
, unsigned long val
,
263 struct cpufreq_policy
*policy
= data
;
264 struct cpufreq_frequency_table
*table
;
265 unsigned int cpu
= policy
->cpu
;
266 if (val
!= CPUFREQ_NOTIFY
)
268 table
= cpufreq_frequency_get_table(cpu
);
271 if ((ret
= cpufreq_stats_create_table(policy
, table
)))
277 cpufreq_stat_notifier_trans (struct notifier_block
*nb
, unsigned long val
,
280 struct cpufreq_freqs
*freq
= data
;
281 struct cpufreq_stats
*stat
;
282 int old_index
, new_index
;
284 if (val
!= CPUFREQ_POSTCHANGE
)
287 stat
= cpufreq_stats_table
[freq
->cpu
];
291 old_index
= stat
->last_index
;
292 new_index
= freq_table_get_index(stat
, freq
->new);
294 cpufreq_stats_update(freq
->cpu
);
295 if (old_index
== new_index
)
298 if (old_index
== -1 || new_index
== -1)
301 spin_lock(&cpufreq_stats_lock
);
302 stat
->last_index
= new_index
;
303 #ifdef CONFIG_CPU_FREQ_STAT_DETAILS
304 stat
->trans_table
[old_index
* stat
->max_state
+ new_index
]++;
307 spin_unlock(&cpufreq_stats_lock
);
311 static int __cpuinit
cpufreq_stat_cpu_callback(struct notifier_block
*nfb
,
312 unsigned long action
,
315 unsigned int cpu
= (unsigned long)hcpu
;
319 case CPU_ONLINE_FROZEN
:
320 cpufreq_update_policy(cpu
);
323 case CPU_DEAD_FROZEN
:
324 cpufreq_stats_free_table(cpu
);
330 static struct notifier_block cpufreq_stat_cpu_notifier __refdata
=
332 .notifier_call
= cpufreq_stat_cpu_callback
,
335 static struct notifier_block notifier_policy_block
= {
336 .notifier_call
= cpufreq_stat_notifier_policy
339 static struct notifier_block notifier_trans_block
= {
340 .notifier_call
= cpufreq_stat_notifier_trans
344 __init
cpufreq_stats_init(void)
349 spin_lock_init(&cpufreq_stats_lock
);
350 if ((ret
= cpufreq_register_notifier(¬ifier_policy_block
,
351 CPUFREQ_POLICY_NOTIFIER
)))
354 if ((ret
= cpufreq_register_notifier(¬ifier_trans_block
,
355 CPUFREQ_TRANSITION_NOTIFIER
))) {
356 cpufreq_unregister_notifier(¬ifier_policy_block
,
357 CPUFREQ_POLICY_NOTIFIER
);
361 register_hotcpu_notifier(&cpufreq_stat_cpu_notifier
);
362 for_each_online_cpu(cpu
) {
363 cpufreq_update_policy(cpu
);
368 __exit
cpufreq_stats_exit(void)
372 cpufreq_unregister_notifier(¬ifier_policy_block
,
373 CPUFREQ_POLICY_NOTIFIER
);
374 cpufreq_unregister_notifier(¬ifier_trans_block
,
375 CPUFREQ_TRANSITION_NOTIFIER
);
376 unregister_hotcpu_notifier(&cpufreq_stat_cpu_notifier
);
377 for_each_online_cpu(cpu
) {
378 cpufreq_stats_free_table(cpu
);
382 MODULE_AUTHOR ("Zou Nan hai <nanhai.zou@intel.com>");
383 MODULE_DESCRIPTION ("'cpufreq_stats' - A driver to export cpufreq stats "
384 "through sysfs filesystem");
385 MODULE_LICENSE ("GPL");
387 module_init(cpufreq_stats_init
);
388 module_exit(cpufreq_stats_exit
);