This source file includes following definitions.
- cpufreq_stats_update
- cpufreq_stats_clear_table
- show_total_trans
- show_time_in_state
- store_reset
- show_trans_table
- freq_table_get_index
- cpufreq_stats_free_table
- cpufreq_stats_create_table
- cpufreq_stats_record_transition
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9 #include <linux/cpu.h>
10 #include <linux/cpufreq.h>
11 #include <linux/module.h>
12 #include <linux/slab.h>
13
14
15 struct cpufreq_stats {
16 unsigned int total_trans;
17 unsigned long long last_time;
18 unsigned int max_state;
19 unsigned int state_num;
20 unsigned int last_index;
21 u64 *time_in_state;
22 spinlock_t lock;
23 unsigned int *freq_table;
24 unsigned int *trans_table;
25 };
26
27 static void cpufreq_stats_update(struct cpufreq_stats *stats)
28 {
29 unsigned long long cur_time = get_jiffies_64();
30
31 stats->time_in_state[stats->last_index] += cur_time - stats->last_time;
32 stats->last_time = cur_time;
33 }
34
35 static void cpufreq_stats_clear_table(struct cpufreq_stats *stats)
36 {
37 unsigned int count = stats->max_state;
38
39 spin_lock(&stats->lock);
40 memset(stats->time_in_state, 0, count * sizeof(u64));
41 memset(stats->trans_table, 0, count * count * sizeof(int));
42 stats->last_time = get_jiffies_64();
43 stats->total_trans = 0;
44 spin_unlock(&stats->lock);
45 }
46
47 static ssize_t show_total_trans(struct cpufreq_policy *policy, char *buf)
48 {
49 return sprintf(buf, "%d\n", policy->stats->total_trans);
50 }
51 cpufreq_freq_attr_ro(total_trans);
52
53 static ssize_t show_time_in_state(struct cpufreq_policy *policy, char *buf)
54 {
55 struct cpufreq_stats *stats = policy->stats;
56 ssize_t len = 0;
57 int i;
58
59 if (policy->fast_switch_enabled)
60 return 0;
61
62 spin_lock(&stats->lock);
63 cpufreq_stats_update(stats);
64 spin_unlock(&stats->lock);
65
66 for (i = 0; i < stats->state_num; i++) {
67 len += sprintf(buf + len, "%u %llu\n", stats->freq_table[i],
68 (unsigned long long)
69 jiffies_64_to_clock_t(stats->time_in_state[i]));
70 }
71 return len;
72 }
73 cpufreq_freq_attr_ro(time_in_state);
74
75 static ssize_t store_reset(struct cpufreq_policy *policy, const char *buf,
76 size_t count)
77 {
78
79 cpufreq_stats_clear_table(policy->stats);
80 return count;
81 }
82 cpufreq_freq_attr_wo(reset);
83
84 static ssize_t show_trans_table(struct cpufreq_policy *policy, char *buf)
85 {
86 struct cpufreq_stats *stats = policy->stats;
87 ssize_t len = 0;
88 int i, j;
89
90 if (policy->fast_switch_enabled)
91 return 0;
92
93 len += snprintf(buf + len, PAGE_SIZE - len, " From : To\n");
94 len += snprintf(buf + len, PAGE_SIZE - len, " : ");
95 for (i = 0; i < stats->state_num; i++) {
96 if (len >= PAGE_SIZE)
97 break;
98 len += snprintf(buf + len, PAGE_SIZE - len, "%9u ",
99 stats->freq_table[i]);
100 }
101 if (len >= PAGE_SIZE)
102 return PAGE_SIZE;
103
104 len += snprintf(buf + len, PAGE_SIZE - len, "\n");
105
106 for (i = 0; i < stats->state_num; i++) {
107 if (len >= PAGE_SIZE)
108 break;
109
110 len += snprintf(buf + len, PAGE_SIZE - len, "%9u: ",
111 stats->freq_table[i]);
112
113 for (j = 0; j < stats->state_num; j++) {
114 if (len >= PAGE_SIZE)
115 break;
116 len += snprintf(buf + len, PAGE_SIZE - len, "%9u ",
117 stats->trans_table[i*stats->max_state+j]);
118 }
119 if (len >= PAGE_SIZE)
120 break;
121 len += snprintf(buf + len, PAGE_SIZE - len, "\n");
122 }
123
124 if (len >= PAGE_SIZE) {
125 pr_warn_once("cpufreq transition table exceeds PAGE_SIZE. Disabling\n");
126 return -EFBIG;
127 }
128 return len;
129 }
130 cpufreq_freq_attr_ro(trans_table);
131
132 static struct attribute *default_attrs[] = {
133 &total_trans.attr,
134 &time_in_state.attr,
135 &reset.attr,
136 &trans_table.attr,
137 NULL
138 };
139 static const struct attribute_group stats_attr_group = {
140 .attrs = default_attrs,
141 .name = "stats"
142 };
143
144 static int freq_table_get_index(struct cpufreq_stats *stats, unsigned int freq)
145 {
146 int index;
147 for (index = 0; index < stats->max_state; index++)
148 if (stats->freq_table[index] == freq)
149 return index;
150 return -1;
151 }
152
153 void cpufreq_stats_free_table(struct cpufreq_policy *policy)
154 {
155 struct cpufreq_stats *stats = policy->stats;
156
157
158 if (!stats)
159 return;
160
161 pr_debug("%s: Free stats table\n", __func__);
162
163 sysfs_remove_group(&policy->kobj, &stats_attr_group);
164 kfree(stats->time_in_state);
165 kfree(stats);
166 policy->stats = NULL;
167 }
168
169 void cpufreq_stats_create_table(struct cpufreq_policy *policy)
170 {
171 unsigned int i = 0, count = 0, ret = -ENOMEM;
172 struct cpufreq_stats *stats;
173 unsigned int alloc_size;
174 struct cpufreq_frequency_table *pos;
175
176 count = cpufreq_table_count_valid_entries(policy);
177 if (!count)
178 return;
179
180
181 if (policy->stats)
182 return;
183
184 stats = kzalloc(sizeof(*stats), GFP_KERNEL);
185 if (!stats)
186 return;
187
188 alloc_size = count * sizeof(int) + count * sizeof(u64);
189
190 alloc_size += count * count * sizeof(int);
191
192
193 stats->time_in_state = kzalloc(alloc_size, GFP_KERNEL);
194 if (!stats->time_in_state)
195 goto free_stat;
196
197 stats->freq_table = (unsigned int *)(stats->time_in_state + count);
198
199 stats->trans_table = stats->freq_table + count;
200
201 stats->max_state = count;
202
203
204 cpufreq_for_each_valid_entry(pos, policy->freq_table)
205 if (freq_table_get_index(stats, pos->frequency) == -1)
206 stats->freq_table[i++] = pos->frequency;
207
208 stats->state_num = i;
209 stats->last_time = get_jiffies_64();
210 stats->last_index = freq_table_get_index(stats, policy->cur);
211 spin_lock_init(&stats->lock);
212
213 policy->stats = stats;
214 ret = sysfs_create_group(&policy->kobj, &stats_attr_group);
215 if (!ret)
216 return;
217
218
219 policy->stats = NULL;
220 kfree(stats->time_in_state);
221 free_stat:
222 kfree(stats);
223 }
224
225 void cpufreq_stats_record_transition(struct cpufreq_policy *policy,
226 unsigned int new_freq)
227 {
228 struct cpufreq_stats *stats = policy->stats;
229 int old_index, new_index;
230
231 if (!stats) {
232 pr_debug("%s: No stats found\n", __func__);
233 return;
234 }
235
236 old_index = stats->last_index;
237 new_index = freq_table_get_index(stats, new_freq);
238
239
240 if (old_index == -1 || new_index == -1 || old_index == new_index)
241 return;
242
243 spin_lock(&stats->lock);
244 cpufreq_stats_update(stats);
245
246 stats->last_index = new_index;
247 stats->trans_table[old_index * stats->max_state + new_index]++;
248 stats->total_trans++;
249 spin_unlock(&stats->lock);
250 }