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path: root/drivers/cpufreq/cpufreq_stats.c
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Diffstat (limited to 'drivers/cpufreq/cpufreq_stats.c')
-rw-r--r--drivers/cpufreq/cpufreq_stats.c219
1 files changed, 97 insertions, 122 deletions
diff --git a/drivers/cpufreq/cpufreq_stats.c b/drivers/cpufreq/cpufreq_stats.c
index 0cd9b4dcef99..5e370a30a964 100644
--- a/drivers/cpufreq/cpufreq_stats.c
+++ b/drivers/cpufreq/cpufreq_stats.c
@@ -18,7 +18,6 @@
static spinlock_t cpufreq_stats_lock;
struct cpufreq_stats {
- unsigned int cpu;
unsigned int total_trans;
unsigned long long last_time;
unsigned int max_state;
@@ -31,50 +30,33 @@ struct cpufreq_stats {
#endif
};
-static DEFINE_PER_CPU(struct cpufreq_stats *, cpufreq_stats_table);
-
-struct cpufreq_stats_attribute {
- struct attribute attr;
- ssize_t(*show) (struct cpufreq_stats *, char *);
-};
-
-static int cpufreq_stats_update(unsigned int cpu)
+static int cpufreq_stats_update(struct cpufreq_stats *stats)
{
- struct cpufreq_stats *stat;
- unsigned long long cur_time;
+ unsigned long long cur_time = get_jiffies_64();
- cur_time = get_jiffies_64();
spin_lock(&cpufreq_stats_lock);
- stat = per_cpu(cpufreq_stats_table, cpu);
- if (stat->time_in_state)
- stat->time_in_state[stat->last_index] +=
- cur_time - stat->last_time;
- stat->last_time = cur_time;
+ stats->time_in_state[stats->last_index] += cur_time - stats->last_time;
+ stats->last_time = cur_time;
spin_unlock(&cpufreq_stats_lock);
return 0;
}
static ssize_t show_total_trans(struct cpufreq_policy *policy, char *buf)
{
- struct cpufreq_stats *stat = per_cpu(cpufreq_stats_table, policy->cpu);
- if (!stat)
- return 0;
- return sprintf(buf, "%d\n",
- per_cpu(cpufreq_stats_table, stat->cpu)->total_trans);
+ return sprintf(buf, "%d\n", policy->stats->total_trans);
}
static ssize_t show_time_in_state(struct cpufreq_policy *policy, char *buf)
{
+ struct cpufreq_stats *stats = policy->stats;
ssize_t len = 0;
int i;
- struct cpufreq_stats *stat = per_cpu(cpufreq_stats_table, policy->cpu);
- if (!stat)
- return 0;
- cpufreq_stats_update(stat->cpu);
- for (i = 0; i < stat->state_num; i++) {
- len += sprintf(buf + len, "%u %llu\n", stat->freq_table[i],
+
+ cpufreq_stats_update(stats);
+ for (i = 0; i < stats->state_num; i++) {
+ len += sprintf(buf + len, "%u %llu\n", stats->freq_table[i],
(unsigned long long)
- jiffies_64_to_clock_t(stat->time_in_state[i]));
+ jiffies_64_to_clock_t(stats->time_in_state[i]));
}
return len;
}
@@ -82,38 +64,35 @@ static ssize_t show_time_in_state(struct cpufreq_policy *policy, char *buf)
#ifdef CONFIG_CPU_FREQ_STAT_DETAILS
static ssize_t show_trans_table(struct cpufreq_policy *policy, char *buf)
{
+ struct cpufreq_stats *stats = policy->stats;
ssize_t len = 0;
int i, j;
- struct cpufreq_stats *stat = per_cpu(cpufreq_stats_table, policy->cpu);
- if (!stat)
- return 0;
- cpufreq_stats_update(stat->cpu);
len += snprintf(buf + len, PAGE_SIZE - len, " From : To\n");
len += snprintf(buf + len, PAGE_SIZE - len, " : ");
- for (i = 0; i < stat->state_num; i++) {
+ for (i = 0; i < stats->state_num; i++) {
if (len >= PAGE_SIZE)
break;
len += snprintf(buf + len, PAGE_SIZE - len, "%9u ",
- stat->freq_table[i]);
+ stats->freq_table[i]);
}
if (len >= PAGE_SIZE)
return PAGE_SIZE;
len += snprintf(buf + len, PAGE_SIZE - len, "\n");
- for (i = 0; i < stat->state_num; i++) {
+ for (i = 0; i < stats->state_num; i++) {
if (len >= PAGE_SIZE)
break;
len += snprintf(buf + len, PAGE_SIZE - len, "%9u: ",
- stat->freq_table[i]);
+ stats->freq_table[i]);
- for (j = 0; j < stat->state_num; j++) {
+ for (j = 0; j < stats->state_num; j++) {
if (len >= PAGE_SIZE)
break;
len += snprintf(buf + len, PAGE_SIZE - len, "%9u ",
- stat->trans_table[i*stat->max_state+j]);
+ stats->trans_table[i*stats->max_state+j]);
}
if (len >= PAGE_SIZE)
break;
@@ -142,28 +121,29 @@ static struct attribute_group stats_attr_group = {
.name = "stats"
};
-static int freq_table_get_index(struct cpufreq_stats *stat, unsigned int freq)
+static int freq_table_get_index(struct cpufreq_stats *stats, unsigned int freq)
{
int index;
- for (index = 0; index < stat->max_state; index++)
- if (stat->freq_table[index] == freq)
+ for (index = 0; index < stats->max_state; index++)
+ if (stats->freq_table[index] == freq)
return index;
return -1;
}
static void __cpufreq_stats_free_table(struct cpufreq_policy *policy)
{
- struct cpufreq_stats *stat = per_cpu(cpufreq_stats_table, policy->cpu);
+ struct cpufreq_stats *stats = policy->stats;
- if (!stat)
+ /* Already freed */
+ if (!stats)
return;
- pr_debug("%s: Free stat table\n", __func__);
+ pr_debug("%s: Free stats table\n", __func__);
sysfs_remove_group(&policy->kobj, &stats_attr_group);
- kfree(stat->time_in_state);
- kfree(stat);
- per_cpu(cpufreq_stats_table, policy->cpu) = NULL;
+ kfree(stats->time_in_state);
+ kfree(stats);
+ policy->stats = NULL;
}
static void cpufreq_stats_free_table(unsigned int cpu)
@@ -174,37 +154,33 @@ static void cpufreq_stats_free_table(unsigned int cpu)
if (!policy)
return;
- if (cpufreq_frequency_get_table(policy->cpu))
- __cpufreq_stats_free_table(policy);
+ __cpufreq_stats_free_table(policy);
cpufreq_cpu_put(policy);
}
static int __cpufreq_stats_create_table(struct cpufreq_policy *policy)
{
- unsigned int i, count = 0, ret = 0;
- struct cpufreq_stats *stat;
+ unsigned int i = 0, count = 0, ret = -ENOMEM;
+ struct cpufreq_stats *stats;
unsigned int alloc_size;
unsigned int cpu = policy->cpu;
struct cpufreq_frequency_table *pos, *table;
+ /* We need cpufreq table for creating stats table */
table = cpufreq_frequency_get_table(cpu);
if (unlikely(!table))
return 0;
- if (per_cpu(cpufreq_stats_table, cpu))
- return -EBUSY;
- stat = kzalloc(sizeof(*stat), GFP_KERNEL);
- if ((stat) == NULL)
- return -ENOMEM;
-
- ret = sysfs_create_group(&policy->kobj, &stats_attr_group);
- if (ret)
- goto error_out;
+ /* stats already initialized */
+ if (policy->stats)
+ return -EEXIST;
- stat->cpu = cpu;
- per_cpu(cpufreq_stats_table, cpu) = stat;
+ stats = kzalloc(sizeof(*stats), GFP_KERNEL);
+ if (!stats)
+ return -ENOMEM;
+ /* Find total allocation size */
cpufreq_for_each_valid_entry(pos, table)
count++;
@@ -213,32 +189,40 @@ static int __cpufreq_stats_create_table(struct cpufreq_policy *policy)
#ifdef CONFIG_CPU_FREQ_STAT_DETAILS
alloc_size += count * count * sizeof(int);
#endif
- stat->max_state = count;
- stat->time_in_state = kzalloc(alloc_size, GFP_KERNEL);
- if (!stat->time_in_state) {
- ret = -ENOMEM;
- goto error_alloc;
- }
- stat->freq_table = (unsigned int *)(stat->time_in_state + count);
+
+ /* Allocate memory for time_in_state/freq_table/trans_table in one go */
+ stats->time_in_state = kzalloc(alloc_size, GFP_KERNEL);
+ if (!stats->time_in_state)
+ goto free_stat;
+
+ stats->freq_table = (unsigned int *)(stats->time_in_state + count);
#ifdef CONFIG_CPU_FREQ_STAT_DETAILS
- stat->trans_table = stat->freq_table + count;
+ stats->trans_table = stats->freq_table + count;
#endif
- i = 0;
+
+ stats->max_state = count;
+
+ /* Find valid-unique entries */
cpufreq_for_each_valid_entry(pos, table)
- if (freq_table_get_index(stat, pos->frequency) == -1)
- stat->freq_table[i++] = pos->frequency;
- stat->state_num = i;
- spin_lock(&cpufreq_stats_lock);
- stat->last_time = get_jiffies_64();
- stat->last_index = freq_table_get_index(stat, policy->cur);
- spin_unlock(&cpufreq_stats_lock);
- return 0;
-error_alloc:
- sysfs_remove_group(&policy->kobj, &stats_attr_group);
-error_out:
- kfree(stat);
- per_cpu(cpufreq_stats_table, cpu) = NULL;
+ if (freq_table_get_index(stats, pos->frequency) == -1)
+ stats->freq_table[i++] = pos->frequency;
+
+ stats->state_num = i;
+ stats->last_time = get_jiffies_64();
+ stats->last_index = freq_table_get_index(stats, policy->cur);
+
+ policy->stats = stats;
+ ret = sysfs_create_group(&policy->kobj, &stats_attr_group);
+ if (!ret)
+ return 0;
+
+ /* We failed, release resources */
+ policy->stats = NULL;
+ kfree(stats->time_in_state);
+free_stat:
+ kfree(stats);
+
return ret;
}
@@ -259,30 +243,12 @@ static void cpufreq_stats_create_table(unsigned int cpu)
cpufreq_cpu_put(policy);
}
-static void cpufreq_stats_update_policy_cpu(struct cpufreq_policy *policy)
-{
- struct cpufreq_stats *stat = per_cpu(cpufreq_stats_table,
- policy->last_cpu);
-
- pr_debug("Updating stats_table for new_cpu %u from last_cpu %u\n",
- policy->cpu, policy->last_cpu);
- per_cpu(cpufreq_stats_table, policy->cpu) = per_cpu(cpufreq_stats_table,
- policy->last_cpu);
- per_cpu(cpufreq_stats_table, policy->last_cpu) = NULL;
- stat->cpu = policy->cpu;
-}
-
static int cpufreq_stat_notifier_policy(struct notifier_block *nb,
unsigned long val, void *data)
{
int ret = 0;
struct cpufreq_policy *policy = data;
- if (val == CPUFREQ_UPDATE_POLICY_CPU) {
- cpufreq_stats_update_policy_cpu(policy);
- return 0;
- }
-
if (val == CPUFREQ_CREATE_POLICY)
ret = __cpufreq_stats_create_table(policy);
else if (val == CPUFREQ_REMOVE_POLICY)
@@ -295,35 +261,45 @@ static int cpufreq_stat_notifier_trans(struct notifier_block *nb,
unsigned long val, void *data)
{
struct cpufreq_freqs *freq = data;
- struct cpufreq_stats *stat;
+ struct cpufreq_policy *policy = cpufreq_cpu_get(freq->cpu);
+ struct cpufreq_stats *stats;
int old_index, new_index;
- if (val != CPUFREQ_POSTCHANGE)
+ if (!policy) {
+ pr_err("%s: No policy found\n", __func__);
return 0;
+ }
- stat = per_cpu(cpufreq_stats_table, freq->cpu);
- if (!stat)
- return 0;
+ if (val != CPUFREQ_POSTCHANGE)
+ goto put_policy;
- old_index = stat->last_index;
- new_index = freq_table_get_index(stat, freq->new);
+ if (!policy->stats) {
+ pr_debug("%s: No stats found\n", __func__);
+ goto put_policy;
+ }
- /* We can't do stat->time_in_state[-1]= .. */
- if (old_index == -1 || new_index == -1)
- return 0;
+ stats = policy->stats;
+
+ old_index = stats->last_index;
+ new_index = freq_table_get_index(stats, freq->new);
- cpufreq_stats_update(freq->cpu);
+ /* We can't do stats->time_in_state[-1]= .. */
+ if (old_index == -1 || new_index == -1)
+ goto put_policy;
if (old_index == new_index)
- return 0;
+ goto put_policy;
- spin_lock(&cpufreq_stats_lock);
- stat->last_index = new_index;
+ cpufreq_stats_update(stats);
+
+ stats->last_index = new_index;
#ifdef CONFIG_CPU_FREQ_STAT_DETAILS
- stat->trans_table[old_index * stat->max_state + new_index]++;
+ stats->trans_table[old_index * stats->max_state + new_index]++;
#endif
- stat->total_trans++;
- spin_unlock(&cpufreq_stats_lock);
+ stats->total_trans++;
+
+put_policy:
+ cpufreq_cpu_put(policy);
return 0;
}
@@ -374,8 +350,7 @@ static void __exit cpufreq_stats_exit(void)
}
MODULE_AUTHOR("Zou Nan hai <nanhai.zou@intel.com>");
-MODULE_DESCRIPTION("'cpufreq_stats' - A driver to export cpufreq stats "
- "through sysfs filesystem");
+MODULE_DESCRIPTION("Export cpufreq stats via sysfs");
MODULE_LICENSE("GPL");
module_init(cpufreq_stats_init);