| /* |
| * drivers/cpufreq/cpufreq_stats.c |
| * |
| * Copyright (C) 2003-2004 Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>. |
| * (C) 2004 Zou Nan hai <nanhai.zou@intel.com>. |
| * |
| * 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 <linux/config.h> |
| #include <linux/kernel.h> |
| #include <linux/sysdev.h> |
| #include <linux/cpu.h> |
| #include <linux/sysfs.h> |
| #include <linux/cpufreq.h> |
| #include <linux/jiffies.h> |
| #include <linux/percpu.h> |
| #include <linux/kobject.h> |
| #include <linux/spinlock.h> |
| #include <asm/cputime.h> |
| |
| static spinlock_t cpufreq_stats_lock; |
| |
| #define CPUFREQ_STATDEVICE_ATTR(_name,_mode,_show) \ |
| static struct freq_attr _attr_##_name = {\ |
| .attr = {.name = __stringify(_name), .owner = THIS_MODULE, \ |
| .mode = _mode, }, \ |
| .show = _show,\ |
| }; |
| |
| struct cpufreq_stats { |
| unsigned int cpu; |
| unsigned int total_trans; |
| unsigned long long last_time; |
| unsigned int max_state; |
| unsigned int state_num; |
| unsigned int last_index; |
| cputime64_t *time_in_state; |
| unsigned int *freq_table; |
| #ifdef CONFIG_CPU_FREQ_STAT_DETAILS |
| unsigned int *trans_table; |
| #endif |
| }; |
| |
| static struct cpufreq_stats *cpufreq_stats_table[NR_CPUS]; |
| |
| struct cpufreq_stats_attribute { |
| struct attribute attr; |
| ssize_t(*show) (struct cpufreq_stats *, char *); |
| }; |
| |
| static int |
| cpufreq_stats_update (unsigned int cpu) |
| { |
| struct cpufreq_stats *stat; |
| unsigned long long cur_time; |
| |
| cur_time = get_jiffies_64(); |
| spin_lock(&cpufreq_stats_lock); |
| stat = cpufreq_stats_table[cpu]; |
| if (stat->time_in_state) |
| stat->time_in_state[stat->last_index] = |
| cputime64_add(stat->time_in_state[stat->last_index], |
| cputime_sub(cur_time, stat->last_time)); |
| stat->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 = cpufreq_stats_table[policy->cpu]; |
| if(!stat) |
| return 0; |
| return sprintf(buf, "%d\n", |
| cpufreq_stats_table[stat->cpu]->total_trans); |
| } |
| |
| static ssize_t |
| show_time_in_state(struct cpufreq_policy *policy, char *buf) |
| { |
| ssize_t len = 0; |
| int i; |
| struct cpufreq_stats *stat = 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], |
| (unsigned long long)cputime64_to_clock_t(stat->time_in_state[i])); |
| } |
| return len; |
| } |
| |
| #ifdef CONFIG_CPU_FREQ_STAT_DETAILS |
| static ssize_t |
| show_trans_table(struct cpufreq_policy *policy, char *buf) |
| { |
| ssize_t len = 0; |
| int i, j; |
| |
| struct cpufreq_stats *stat = 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++) { |
| if (len >= PAGE_SIZE) |
| break; |
| len += snprintf(buf + len, PAGE_SIZE - len, "%9u ", |
| stat->freq_table[i]); |
| } |
| if (len >= PAGE_SIZE) |
| return len; |
| |
| len += snprintf(buf + len, PAGE_SIZE - len, "\n"); |
| |
| for (i = 0; i < stat->state_num; i++) { |
| if (len >= PAGE_SIZE) |
| break; |
| |
| len += snprintf(buf + len, PAGE_SIZE - len, "%9u: ", |
| stat->freq_table[i]); |
| |
| for (j = 0; j < stat->state_num; j++) { |
| if (len >= PAGE_SIZE) |
| break; |
| len += snprintf(buf + len, PAGE_SIZE - len, "%9u ", |
| stat->trans_table[i*stat->max_state+j]); |
| } |
| len += snprintf(buf + len, PAGE_SIZE - len, "\n"); |
| } |
| return len; |
| } |
| CPUFREQ_STATDEVICE_ATTR(trans_table,0444,show_trans_table); |
| #endif |
| |
| CPUFREQ_STATDEVICE_ATTR(total_trans,0444,show_total_trans); |
| CPUFREQ_STATDEVICE_ATTR(time_in_state,0444,show_time_in_state); |
| |
| static struct attribute *default_attrs[] = { |
| &_attr_total_trans.attr, |
| &_attr_time_in_state.attr, |
| #ifdef CONFIG_CPU_FREQ_STAT_DETAILS |
| &_attr_trans_table.attr, |
| #endif |
| NULL |
| }; |
| static struct attribute_group stats_attr_group = { |
| .attrs = default_attrs, |
| .name = "stats" |
| }; |
| |
| static int |
| freq_table_get_index(struct cpufreq_stats *stat, unsigned int freq) |
| { |
| int index; |
| for (index = 0; index < stat->max_state; index++) |
| if (stat->freq_table[index] == freq) |
| return index; |
| return -1; |
| } |
| |
| static void |
| cpufreq_stats_free_table (unsigned int cpu) |
| { |
| struct cpufreq_stats *stat = cpufreq_stats_table[cpu]; |
| struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); |
| if (policy && policy->cpu == cpu) |
| sysfs_remove_group(&policy->kobj, &stats_attr_group); |
| if (stat) { |
| kfree(stat->time_in_state); |
| kfree(stat); |
| } |
| cpufreq_stats_table[cpu] = NULL; |
| if (policy) |
| cpufreq_cpu_put(policy); |
| } |
| |
| static int |
| cpufreq_stats_create_table (struct cpufreq_policy *policy, |
| struct cpufreq_frequency_table *table) |
| { |
| unsigned int i, j, count = 0, ret = 0; |
| struct cpufreq_stats *stat; |
| struct cpufreq_policy *data; |
| unsigned int alloc_size; |
| unsigned int cpu = policy->cpu; |
| if (cpufreq_stats_table[cpu]) |
| return -EBUSY; |
| if ((stat = kzalloc(sizeof(struct cpufreq_stats), GFP_KERNEL)) == NULL) |
| return -ENOMEM; |
| |
| data = cpufreq_cpu_get(cpu); |
| if ((ret = sysfs_create_group(&data->kobj, &stats_attr_group))) |
| goto error_out; |
| |
| stat->cpu = cpu; |
| cpufreq_stats_table[cpu] = stat; |
| |
| for (i=0; table[i].frequency != CPUFREQ_TABLE_END; i++) { |
| unsigned int freq = table[i].frequency; |
| if (freq == CPUFREQ_ENTRY_INVALID) |
| continue; |
| count++; |
| } |
| |
| alloc_size = count * sizeof(int) + count * sizeof(cputime64_t); |
| |
| #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_out; |
| } |
| stat->freq_table = (unsigned int *)(stat->time_in_state + count); |
| |
| #ifdef CONFIG_CPU_FREQ_STAT_DETAILS |
| stat->trans_table = stat->freq_table + count; |
| #endif |
| j = 0; |
| for (i = 0; table[i].frequency != CPUFREQ_TABLE_END; i++) { |
| unsigned int freq = table[i].frequency; |
| if (freq == CPUFREQ_ENTRY_INVALID) |
| continue; |
| if (freq_table_get_index(stat, freq) == -1) |
| stat->freq_table[j++] = freq; |
| } |
| stat->state_num = j; |
| 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); |
| cpufreq_cpu_put(data); |
| return 0; |
| error_out: |
| cpufreq_cpu_put(data); |
| kfree(stat); |
| cpufreq_stats_table[cpu] = NULL; |
| return ret; |
| } |
| |
| static int |
| cpufreq_stat_notifier_policy (struct notifier_block *nb, unsigned long val, |
| void *data) |
| { |
| int ret; |
| struct cpufreq_policy *policy = data; |
| struct cpufreq_frequency_table *table; |
| unsigned int cpu = policy->cpu; |
| if (val != CPUFREQ_NOTIFY) |
| return 0; |
| table = cpufreq_frequency_get_table(cpu); |
| if (!table) |
| return 0; |
| if ((ret = cpufreq_stats_create_table(policy, table))) |
| return ret; |
| return 0; |
| } |
| |
| static int |
| cpufreq_stat_notifier_trans (struct notifier_block *nb, unsigned long val, |
| void *data) |
| { |
| struct cpufreq_freqs *freq = data; |
| struct cpufreq_stats *stat; |
| int old_index, new_index; |
| |
| if (val != CPUFREQ_POSTCHANGE) |
| return 0; |
| |
| stat = cpufreq_stats_table[freq->cpu]; |
| if (!stat) |
| return 0; |
| old_index = freq_table_get_index(stat, freq->old); |
| new_index = freq_table_get_index(stat, freq->new); |
| |
| cpufreq_stats_update(freq->cpu); |
| if (old_index == new_index) |
| return 0; |
| |
| spin_lock(&cpufreq_stats_lock); |
| stat->last_index = new_index; |
| #ifdef CONFIG_CPU_FREQ_STAT_DETAILS |
| stat->trans_table[old_index * stat->max_state + new_index]++; |
| #endif |
| stat->total_trans++; |
| spin_unlock(&cpufreq_stats_lock); |
| return 0; |
| } |
| |
| static struct notifier_block notifier_policy_block = { |
| .notifier_call = cpufreq_stat_notifier_policy |
| }; |
| |
| static struct notifier_block notifier_trans_block = { |
| .notifier_call = cpufreq_stat_notifier_trans |
| }; |
| |
| static int |
| __init cpufreq_stats_init(void) |
| { |
| int ret; |
| unsigned int cpu; |
| spin_lock_init(&cpufreq_stats_lock); |
| if ((ret = cpufreq_register_notifier(¬ifier_policy_block, |
| CPUFREQ_POLICY_NOTIFIER))) |
| return ret; |
| |
| if ((ret = cpufreq_register_notifier(¬ifier_trans_block, |
| CPUFREQ_TRANSITION_NOTIFIER))) { |
| cpufreq_unregister_notifier(¬ifier_policy_block, |
| CPUFREQ_POLICY_NOTIFIER); |
| return ret; |
| } |
| |
| for_each_cpu(cpu) |
| cpufreq_update_policy(cpu); |
| return 0; |
| } |
| static void |
| __exit cpufreq_stats_exit(void) |
| { |
| unsigned int cpu; |
| cpufreq_unregister_notifier(¬ifier_policy_block, |
| CPUFREQ_POLICY_NOTIFIER); |
| cpufreq_unregister_notifier(¬ifier_trans_block, |
| CPUFREQ_TRANSITION_NOTIFIER); |
| for_each_cpu(cpu) |
| cpufreq_stats_free_table(cpu); |
| } |
| |
| MODULE_AUTHOR ("Zou Nan hai <nanhai.zou@intel.com>"); |
| MODULE_DESCRIPTION ("'cpufreq_stats' - A driver to export cpufreq stats through sysfs filesystem"); |
| MODULE_LICENSE ("GPL"); |
| |
| module_init(cpufreq_stats_init); |
| module_exit(cpufreq_stats_exit); |