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/cpu.h>
13 #include <linux/cpufreq.h>
14 #include <linux/module.h>
15 #include <linux/slab.h>
17 static DEFINE_SPINLOCK(cpufreq_stats_lock
);
19 struct cpufreq_stats
{
20 unsigned int total_trans
;
21 unsigned long long last_time
;
22 unsigned int max_state
;
23 unsigned int state_num
;
24 unsigned int last_index
;
26 unsigned int *freq_table
;
27 #ifdef CONFIG_CPU_FREQ_STAT_DETAILS
28 unsigned int *trans_table
;
32 static int cpufreq_stats_update(struct cpufreq_stats
*stats
)
34 unsigned long long cur_time
= get_jiffies_64();
36 spin_lock(&cpufreq_stats_lock
);
37 stats
->time_in_state
[stats
->last_index
] += cur_time
- stats
->last_time
;
38 stats
->last_time
= cur_time
;
39 spin_unlock(&cpufreq_stats_lock
);
43 static void cpufreq_stats_clear_table(struct cpufreq_stats
*stats
)
45 unsigned int count
= stats
->max_state
;
47 memset(stats
->time_in_state
, 0, count
* sizeof(u64
));
48 #ifdef CONFIG_CPU_FREQ_STAT_DETAILS
49 memset(stats
->trans_table
, 0, count
* count
* sizeof(int));
51 stats
->last_time
= get_jiffies_64();
52 stats
->total_trans
= 0;
55 static ssize_t
show_total_trans(struct cpufreq_policy
*policy
, char *buf
)
57 return sprintf(buf
, "%d\n", policy
->stats
->total_trans
);
60 static ssize_t
show_time_in_state(struct cpufreq_policy
*policy
, char *buf
)
62 struct cpufreq_stats
*stats
= policy
->stats
;
66 if (policy
->fast_switch_enabled
)
69 cpufreq_stats_update(stats
);
70 for (i
= 0; i
< stats
->state_num
; i
++) {
71 len
+= sprintf(buf
+ len
, "%u %llu\n", stats
->freq_table
[i
],
73 jiffies_64_to_clock_t(stats
->time_in_state
[i
]));
78 static ssize_t
store_reset(struct cpufreq_policy
*policy
, const char *buf
,
81 /* We don't care what is written to the attribute. */
82 cpufreq_stats_clear_table(policy
->stats
);
86 #ifdef CONFIG_CPU_FREQ_STAT_DETAILS
87 static ssize_t
show_trans_table(struct cpufreq_policy
*policy
, char *buf
)
89 struct cpufreq_stats
*stats
= policy
->stats
;
93 if (policy
->fast_switch_enabled
)
96 len
+= snprintf(buf
+ len
, PAGE_SIZE
- len
, " From : To\n");
97 len
+= snprintf(buf
+ len
, PAGE_SIZE
- len
, " : ");
98 for (i
= 0; i
< stats
->state_num
; i
++) {
101 len
+= snprintf(buf
+ len
, PAGE_SIZE
- len
, "%9u ",
102 stats
->freq_table
[i
]);
104 if (len
>= PAGE_SIZE
)
107 len
+= snprintf(buf
+ len
, PAGE_SIZE
- len
, "\n");
109 for (i
= 0; i
< stats
->state_num
; i
++) {
110 if (len
>= PAGE_SIZE
)
113 len
+= snprintf(buf
+ len
, PAGE_SIZE
- len
, "%9u: ",
114 stats
->freq_table
[i
]);
116 for (j
= 0; j
< stats
->state_num
; j
++) {
117 if (len
>= PAGE_SIZE
)
119 len
+= snprintf(buf
+ len
, PAGE_SIZE
- len
, "%9u ",
120 stats
->trans_table
[i
*stats
->max_state
+j
]);
122 if (len
>= PAGE_SIZE
)
124 len
+= snprintf(buf
+ len
, PAGE_SIZE
- len
, "\n");
126 if (len
>= PAGE_SIZE
)
130 cpufreq_freq_attr_ro(trans_table
);
133 cpufreq_freq_attr_ro(total_trans
);
134 cpufreq_freq_attr_ro(time_in_state
);
135 cpufreq_freq_attr_wo(reset
);
137 static struct attribute
*default_attrs
[] = {
141 #ifdef CONFIG_CPU_FREQ_STAT_DETAILS
146 static struct attribute_group stats_attr_group
= {
147 .attrs
= default_attrs
,
151 static int freq_table_get_index(struct cpufreq_stats
*stats
, unsigned int freq
)
154 for (index
= 0; index
< stats
->max_state
; index
++)
155 if (stats
->freq_table
[index
] == freq
)
160 void cpufreq_stats_free_table(struct cpufreq_policy
*policy
)
162 struct cpufreq_stats
*stats
= policy
->stats
;
168 pr_debug("%s: Free stats table\n", __func__
);
170 sysfs_remove_group(&policy
->kobj
, &stats_attr_group
);
171 kfree(stats
->time_in_state
);
173 policy
->stats
= NULL
;
176 void cpufreq_stats_create_table(struct cpufreq_policy
*policy
)
178 unsigned int i
= 0, count
= 0, ret
= -ENOMEM
;
179 struct cpufreq_stats
*stats
;
180 unsigned int alloc_size
;
181 struct cpufreq_frequency_table
*pos
, *table
;
183 /* We need cpufreq table for creating stats table */
184 table
= policy
->freq_table
;
185 if (unlikely(!table
))
188 /* stats already initialized */
192 stats
= kzalloc(sizeof(*stats
), GFP_KERNEL
);
196 /* Find total allocation size */
197 cpufreq_for_each_valid_entry(pos
, table
)
200 alloc_size
= count
* sizeof(int) + count
* sizeof(u64
);
202 #ifdef CONFIG_CPU_FREQ_STAT_DETAILS
203 alloc_size
+= count
* count
* sizeof(int);
206 /* Allocate memory for time_in_state/freq_table/trans_table in one go */
207 stats
->time_in_state
= kzalloc(alloc_size
, GFP_KERNEL
);
208 if (!stats
->time_in_state
)
211 stats
->freq_table
= (unsigned int *)(stats
->time_in_state
+ count
);
213 #ifdef CONFIG_CPU_FREQ_STAT_DETAILS
214 stats
->trans_table
= stats
->freq_table
+ count
;
217 stats
->max_state
= count
;
219 /* Find valid-unique entries */
220 cpufreq_for_each_valid_entry(pos
, table
)
221 if (freq_table_get_index(stats
, pos
->frequency
) == -1)
222 stats
->freq_table
[i
++] = pos
->frequency
;
224 stats
->state_num
= i
;
225 stats
->last_time
= get_jiffies_64();
226 stats
->last_index
= freq_table_get_index(stats
, policy
->cur
);
228 policy
->stats
= stats
;
229 ret
= sysfs_create_group(&policy
->kobj
, &stats_attr_group
);
233 /* We failed, release resources */
234 policy
->stats
= NULL
;
235 kfree(stats
->time_in_state
);
240 void cpufreq_stats_record_transition(struct cpufreq_policy
*policy
,
241 unsigned int new_freq
)
243 struct cpufreq_stats
*stats
= policy
->stats
;
244 int old_index
, new_index
;
247 pr_debug("%s: No stats found\n", __func__
);
251 old_index
= stats
->last_index
;
252 new_index
= freq_table_get_index(stats
, new_freq
);
254 /* We can't do stats->time_in_state[-1]= .. */
255 if (old_index
== -1 || new_index
== -1 || old_index
== new_index
)
258 cpufreq_stats_update(stats
);
260 stats
->last_index
= new_index
;
261 #ifdef CONFIG_CPU_FREQ_STAT_DETAILS
262 stats
->trans_table
[old_index
* stats
->max_state
+ new_index
]++;
264 stats
->total_trans
++;