/* * drivers/cpufreq/cpufreq_stats.c * * Copyright (C) 2003-2004 Venkatesh Pallipadi . * (C) 2004 Zou Nan hai . * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as * published by the Free Software Foundation. */ #include #include #include #include static DEFINE_SPINLOCK(cpufreq_stats_lock); struct cpufreq_stats { unsigned int total_trans; unsigned long long last_time; unsigned int max_state; unsigned int state_num; unsigned int last_index; u64 *time_in_state; unsigned int *freq_table; unsigned int *trans_table; }; static void cpufreq_stats_update(struct cpufreq_stats *stats) { unsigned long long cur_time = get_jiffies_64(); spin_lock(&cpufreq_stats_lock); stats->time_in_state[stats->last_index] += cur_time - stats->last_time; stats->last_time = cur_time; spin_unlock(&cpufreq_stats_lock); } static void cpufreq_stats_clear_table(struct cpufreq_stats *stats) { unsigned int count = stats->max_state; memset(stats->time_in_state, 0, count * sizeof(u64)); memset(stats->trans_table, 0, count * count * sizeof(int)); stats->last_time = get_jiffies_64(); stats->total_trans = 0; } static ssize_t show_total_trans(struct cpufreq_policy *policy, char *buf) { 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; if (policy->fast_switch_enabled) return 0; 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(stats->time_in_state[i])); } return len; } static ssize_t store_reset(struct cpufreq_policy *policy, const char *buf, size_t count) { /* We don't care what is written to the attribute. */ cpufreq_stats_clear_table(policy->stats); return count; } 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; if (policy->fast_switch_enabled) return 0; len += snprintf(buf + len, PAGE_SIZE - len, " From : To\n"); len += snprintf(buf + len, PAGE_SIZE - len, " : "); for (i = 0; i < stats->state_num; i++) { if (len >= PAGE_SIZE) break; len += snprintf(buf + len, PAGE_SIZE - len, "%9u ", stats->freq_table[i]); } if (len >= PAGE_SIZE) return PAGE_SIZE; len += snprintf(buf + len, PAGE_SIZE - len, "\n"); for (i = 0; i < stats->state_num; i++) { if (len >= PAGE_SIZE) break; len += snprintf(buf + len, PAGE_SIZE - len, "%9u: ", stats->freq_table[i]); for (j = 0; j < stats->state_num; j++) { if (len >= PAGE_SIZE) break; len += snprintf(buf + len, PAGE_SIZE - len, "%9u ", stats->trans_table[i*stats->max_state+j]); } if (len >= PAGE_SIZE) break; len += snprintf(buf + len, PAGE_SIZE - len, "\n"); } if (len >= PAGE_SIZE) { pr_warn_once("cpufreq transition table exceeds PAGE_SIZE. Disabling\n"); return -EFBIG; } return len; } cpufreq_freq_attr_ro(trans_table); cpufreq_freq_attr_ro(total_trans); cpufreq_freq_attr_ro(time_in_state); cpufreq_freq_attr_wo(reset); static struct attribute *default_attrs[] = { &total_trans.attr, &time_in_state.attr, &reset.attr, &trans_table.attr, NULL }; static const struct attribute_group stats_attr_group = { .attrs = default_attrs, .name = "stats" }; static int freq_table_get_index(struct cpufreq_stats *stats, unsigned int freq) { int index; for (index = 0; index < stats->max_state; index++) if (stats->freq_table[index] == freq) return index; return -1; } void cpufreq_stats_free_table(struct cpufreq_policy *policy) { struct cpufreq_stats *stats = policy->stats; /* Already freed */ if (!stats) return; pr_debug("%s: Free stats table\n", __func__); sysfs_remove_group(&policy->kobj, &stats_attr_group); kfree(stats->time_in_state); kfree(stats); policy->stats = NULL; } void cpufreq_stats_create_table(struct cpufreq_policy *policy) { unsigned int i = 0, count = 0, ret = -ENOMEM; struct cpufreq_stats *stats; unsigned int alloc_size; struct cpufreq_frequency_table *pos; count = cpufreq_table_count_valid_entries(policy); if (!count) return; /* stats already initialized */ if (policy->stats) return; stats = kzalloc(sizeof(*stats), GFP_KERNEL); if (!stats) return; alloc_size = count * sizeof(int) + count * sizeof(u64); alloc_size += count * count * sizeof(int); /* 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); stats->trans_table = stats->freq_table + count; stats->max_state = count; /* Find valid-unique entries */ cpufreq_for_each_valid_entry(pos, policy->freq_table) 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; /* We failed, release resources */ policy->stats = NULL; kfree(stats->time_in_state); free_stat: kfree(stats); } void cpufreq_stats_record_transition(struct cpufreq_policy *policy, unsigned int new_freq) { struct cpufreq_stats *stats = policy->stats; int old_index, new_index; if (!stats) { pr_debug("%s: No stats found\n", __func__); return; } old_index = stats->last_index; new_index = freq_table_get_index(stats, new_freq); /* We can't do stats->time_in_state[-1]= .. */ if (old_index == -1 || new_index == -1 || old_index == new_index) return; cpufreq_stats_update(stats); stats->last_index = new_index; stats->trans_table[old_index * stats->max_state + new_index]++; stats->total_trans++; }