2005-04-16 22:20:36 +00:00
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/*
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* drivers/cpufreq/cpufreq_stats.c
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*
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* Copyright (C) 2003-2004 Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>.
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2009-01-18 06:49:04 +00:00
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* (C) 2004 Zou Nan hai <nanhai.zou@intel.com>.
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2005-04-16 22:20:36 +00:00
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*/
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#include <linux/cpu.h>
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#include <linux/cpufreq.h>
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2011-05-27 17:23:32 +00:00
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#include <linux/module.h>
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2013-08-06 17:23:03 +00:00
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#include <linux/slab.h>
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2005-05-25 21:46:50 +00:00
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#include <asm/cputime.h>
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2005-04-16 22:20:36 +00:00
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static spinlock_t cpufreq_stats_lock;
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struct cpufreq_stats {
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unsigned int cpu;
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unsigned int total_trans;
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2013-06-19 08:49:33 +00:00
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unsigned long long last_time;
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2005-04-16 22:20:36 +00:00
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unsigned int max_state;
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unsigned int state_num;
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unsigned int last_index;
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2012-10-25 22:51:21 +00:00
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u64 *time_in_state;
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2005-04-16 22:20:36 +00:00
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unsigned int *freq_table;
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#ifdef CONFIG_CPU_FREQ_STAT_DETAILS
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unsigned int *trans_table;
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#endif
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};
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2008-03-25 22:06:53 +00:00
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static DEFINE_PER_CPU(struct cpufreq_stats *, cpufreq_stats_table);
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2005-04-16 22:20:36 +00:00
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struct cpufreq_stats_attribute {
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struct attribute attr;
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ssize_t(*show) (struct cpufreq_stats *, char *);
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};
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2009-01-18 06:49:04 +00:00
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static int cpufreq_stats_update(unsigned int cpu)
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2005-04-16 22:20:36 +00:00
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{
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struct cpufreq_stats *stat;
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2005-05-25 21:46:50 +00:00
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unsigned long long cur_time;
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cur_time = get_jiffies_64();
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2005-04-16 22:20:36 +00:00
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spin_lock(&cpufreq_stats_lock);
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2008-03-25 22:06:53 +00:00
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stat = per_cpu(cpufreq_stats_table, cpu);
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2005-04-16 22:20:36 +00:00
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if (stat->time_in_state)
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2011-12-15 13:56:09 +00:00
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stat->time_in_state[stat->last_index] +=
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cur_time - stat->last_time;
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2005-05-25 21:46:50 +00:00
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stat->last_time = cur_time;
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2005-04-16 22:20:36 +00:00
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spin_unlock(&cpufreq_stats_lock);
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return 0;
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}
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2009-01-18 06:49:04 +00:00
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static ssize_t show_total_trans(struct cpufreq_policy *policy, char *buf)
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2005-04-16 22:20:36 +00:00
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{
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2008-03-25 22:06:53 +00:00
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struct cpufreq_stats *stat = per_cpu(cpufreq_stats_table, policy->cpu);
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2006-05-30 21:57:14 +00:00
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if (!stat)
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2005-04-16 22:20:36 +00:00
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return 0;
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return sprintf(buf, "%d\n",
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2008-03-25 22:06:53 +00:00
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per_cpu(cpufreq_stats_table, stat->cpu)->total_trans);
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2005-04-16 22:20:36 +00:00
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}
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2009-01-18 06:49:04 +00:00
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static ssize_t show_time_in_state(struct cpufreq_policy *policy, char *buf)
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2005-04-16 22:20:36 +00:00
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{
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ssize_t len = 0;
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int i;
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2008-03-25 22:06:53 +00:00
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struct cpufreq_stats *stat = per_cpu(cpufreq_stats_table, policy->cpu);
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2006-05-30 21:57:14 +00:00
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if (!stat)
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2005-04-16 22:20:36 +00:00
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return 0;
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cpufreq_stats_update(stat->cpu);
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for (i = 0; i < stat->state_num; i++) {
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2006-02-28 05:43:23 +00:00
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len += sprintf(buf + len, "%u %llu\n", stat->freq_table[i],
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2009-01-18 06:49:04 +00:00
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(unsigned long long)
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2013-09-07 16:35:08 +00:00
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jiffies_64_to_clock_t(stat->time_in_state[i]));
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2005-04-16 22:20:36 +00:00
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}
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return len;
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}
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#ifdef CONFIG_CPU_FREQ_STAT_DETAILS
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2009-01-18 06:49:04 +00:00
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static ssize_t show_trans_table(struct cpufreq_policy *policy, char *buf)
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2005-04-16 22:20:36 +00:00
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{
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ssize_t len = 0;
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int i, j;
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2008-03-25 22:06:53 +00:00
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struct cpufreq_stats *stat = per_cpu(cpufreq_stats_table, policy->cpu);
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2006-05-30 21:57:14 +00:00
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if (!stat)
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2005-04-16 22:20:36 +00:00
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return 0;
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cpufreq_stats_update(stat->cpu);
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2005-05-25 21:46:50 +00:00
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len += snprintf(buf + len, PAGE_SIZE - len, " From : To\n");
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len += snprintf(buf + len, PAGE_SIZE - len, " : ");
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for (i = 0; i < stat->state_num; i++) {
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if (len >= PAGE_SIZE)
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break;
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len += snprintf(buf + len, PAGE_SIZE - len, "%9u ",
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stat->freq_table[i]);
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}
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if (len >= PAGE_SIZE)
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2008-02-16 10:41:25 +00:00
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return PAGE_SIZE;
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2005-05-25 21:46:50 +00:00
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len += snprintf(buf + len, PAGE_SIZE - len, "\n");
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2005-04-16 22:20:36 +00:00
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for (i = 0; i < stat->state_num; i++) {
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if (len >= PAGE_SIZE)
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break;
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2005-05-25 21:46:50 +00:00
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len += snprintf(buf + len, PAGE_SIZE - len, "%9u: ",
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2005-04-16 22:20:36 +00:00
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stat->freq_table[i]);
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2013-06-19 08:49:33 +00:00
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for (j = 0; j < stat->state_num; j++) {
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2005-04-16 22:20:36 +00:00
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if (len >= PAGE_SIZE)
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break;
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2005-05-25 21:46:50 +00:00
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len += snprintf(buf + len, PAGE_SIZE - len, "%9u ",
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2005-04-16 22:20:36 +00:00
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stat->trans_table[i*stat->max_state+j]);
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}
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2008-02-16 10:41:25 +00:00
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if (len >= PAGE_SIZE)
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break;
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2005-04-16 22:20:36 +00:00
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len += snprintf(buf + len, PAGE_SIZE - len, "\n");
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}
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2008-02-16 10:41:25 +00:00
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if (len >= PAGE_SIZE)
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return PAGE_SIZE;
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2005-04-16 22:20:36 +00:00
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return len;
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}
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2013-02-04 11:38:52 +00:00
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cpufreq_freq_attr_ro(trans_table);
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2005-04-16 22:20:36 +00:00
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#endif
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2013-02-04 11:38:52 +00:00
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cpufreq_freq_attr_ro(total_trans);
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cpufreq_freq_attr_ro(time_in_state);
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2005-04-16 22:20:36 +00:00
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static struct attribute *default_attrs[] = {
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2013-02-04 11:38:52 +00:00
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&total_trans.attr,
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&time_in_state.attr,
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2005-04-16 22:20:36 +00:00
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#ifdef CONFIG_CPU_FREQ_STAT_DETAILS
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2013-02-04 11:38:52 +00:00
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&trans_table.attr,
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2005-04-16 22:20:36 +00:00
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#endif
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NULL
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};
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static struct attribute_group stats_attr_group = {
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.attrs = default_attrs,
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.name = "stats"
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};
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2009-01-18 06:49:04 +00:00
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static int freq_table_get_index(struct cpufreq_stats *stat, unsigned int freq)
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2005-04-16 22:20:36 +00:00
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{
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int index;
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for (index = 0; index < stat->max_state; index++)
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if (stat->freq_table[index] == freq)
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return index;
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return -1;
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}
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2014-01-07 01:40:12 +00:00
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static void __cpufreq_stats_free_table(struct cpufreq_policy *policy)
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2005-04-16 22:20:36 +00:00
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{
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2014-01-07 01:40:12 +00:00
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struct cpufreq_stats *stat = per_cpu(cpufreq_stats_table, policy->cpu);
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2013-01-14 13:23:03 +00:00
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2014-01-07 01:40:12 +00:00
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if (!stat)
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return;
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pr_debug("%s: Free stat table\n", __func__);
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sysfs_remove_group(&policy->kobj, &stats_attr_group);
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kfree(stat->time_in_state);
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kfree(stat);
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per_cpu(cpufreq_stats_table, policy->cpu) = NULL;
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2011-05-02 18:29:17 +00:00
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}
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2014-01-07 01:40:12 +00:00
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static void cpufreq_stats_free_table(unsigned int cpu)
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2011-05-02 18:29:17 +00:00
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{
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2014-01-07 01:40:12 +00:00
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struct cpufreq_policy *policy;
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2013-02-06 17:02:12 +00:00
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2014-01-07 01:40:12 +00:00
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policy = cpufreq_cpu_get(cpu);
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2013-03-22 10:13:52 +00:00
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if (!policy)
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2013-02-06 17:02:12 +00:00
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return;
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2014-01-07 01:40:12 +00:00
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if (cpufreq_frequency_get_table(policy->cpu))
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__cpufreq_stats_free_table(policy);
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2013-03-22 10:13:52 +00:00
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cpufreq_cpu_put(policy);
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2005-04-16 22:20:36 +00:00
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}
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2009-01-18 06:49:04 +00:00
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static int cpufreq_stats_create_table(struct cpufreq_policy *policy,
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2005-04-16 22:20:36 +00:00
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struct cpufreq_frequency_table *table)
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{
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unsigned int i, j, count = 0, ret = 0;
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struct cpufreq_stats *stat;
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2013-08-06 17:23:05 +00:00
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struct cpufreq_policy *current_policy;
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2005-04-16 22:20:36 +00:00
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unsigned int alloc_size;
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unsigned int cpu = policy->cpu;
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2008-03-25 22:06:53 +00:00
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if (per_cpu(cpufreq_stats_table, cpu))
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2005-04-16 22:20:36 +00:00
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return -EBUSY;
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2013-08-06 17:23:06 +00:00
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stat = kzalloc(sizeof(*stat), GFP_KERNEL);
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2009-01-18 06:49:04 +00:00
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if ((stat) == NULL)
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2005-04-16 22:20:36 +00:00
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return -ENOMEM;
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2013-08-06 17:23:05 +00:00
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current_policy = cpufreq_cpu_get(cpu);
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if (current_policy == NULL) {
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2005-10-27 23:02:06 +00:00
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ret = -EINVAL;
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goto error_get_fail;
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}
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2013-08-06 17:23:05 +00:00
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ret = sysfs_create_group(¤t_policy->kobj, &stats_attr_group);
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2009-01-18 06:49:04 +00:00
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if (ret)
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2005-04-16 22:20:36 +00:00
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goto error_out;
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stat->cpu = cpu;
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2008-03-25 22:06:53 +00:00
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per_cpu(cpufreq_stats_table, cpu) = stat;
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2005-04-16 22:20:36 +00:00
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2009-01-18 06:49:04 +00:00
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for (i = 0; table[i].frequency != CPUFREQ_TABLE_END; i++) {
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2005-04-16 22:20:36 +00:00
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unsigned int freq = table[i].frequency;
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if (freq == CPUFREQ_ENTRY_INVALID)
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continue;
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count++;
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}
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2012-10-25 22:51:21 +00:00
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alloc_size = count * sizeof(int) + count * sizeof(u64);
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2005-04-16 22:20:36 +00:00
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#ifdef CONFIG_CPU_FREQ_STAT_DETAILS
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alloc_size += count * count * sizeof(int);
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#endif
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stat->max_state = count;
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2005-10-20 22:17:43 +00:00
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stat->time_in_state = kzalloc(alloc_size, GFP_KERNEL);
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2005-04-16 22:20:36 +00:00
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if (!stat->time_in_state) {
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ret = -ENOMEM;
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goto error_out;
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}
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stat->freq_table = (unsigned int *)(stat->time_in_state + count);
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#ifdef CONFIG_CPU_FREQ_STAT_DETAILS
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stat->trans_table = stat->freq_table + count;
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#endif
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j = 0;
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for (i = 0; table[i].frequency != CPUFREQ_TABLE_END; i++) {
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unsigned int freq = table[i].frequency;
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if (freq == CPUFREQ_ENTRY_INVALID)
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continue;
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if (freq_table_get_index(stat, freq) == -1)
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stat->freq_table[j++] = freq;
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}
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stat->state_num = j;
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spin_lock(&cpufreq_stats_lock);
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2005-05-25 21:46:50 +00:00
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stat->last_time = get_jiffies_64();
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2005-04-16 22:20:36 +00:00
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stat->last_index = freq_table_get_index(stat, policy->cur);
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spin_unlock(&cpufreq_stats_lock);
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2013-08-06 17:23:05 +00:00
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cpufreq_cpu_put(current_policy);
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2005-04-16 22:20:36 +00:00
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return 0;
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error_out:
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2013-08-06 17:23:05 +00:00
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cpufreq_cpu_put(current_policy);
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2005-11-02 07:13:45 +00:00
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error_get_fail:
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2005-04-16 22:20:36 +00:00
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kfree(stat);
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2008-03-25 22:06:53 +00:00
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per_cpu(cpufreq_stats_table, cpu) = NULL;
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2005-04-16 22:20:36 +00:00
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return ret;
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}
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|
2013-01-14 13:23:03 +00:00
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static void cpufreq_stats_update_policy_cpu(struct cpufreq_policy *policy)
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{
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struct cpufreq_stats *stat = per_cpu(cpufreq_stats_table,
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policy->last_cpu);
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pr_debug("Updating stats_table for new_cpu %u from last_cpu %u\n",
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policy->cpu, policy->last_cpu);
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per_cpu(cpufreq_stats_table, policy->cpu) = per_cpu(cpufreq_stats_table,
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policy->last_cpu);
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per_cpu(cpufreq_stats_table, policy->last_cpu) = NULL;
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stat->cpu = policy->cpu;
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}
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|
2009-01-18 06:49:04 +00:00
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static int cpufreq_stat_notifier_policy(struct notifier_block *nb,
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unsigned long val, void *data)
|
2005-04-16 22:20:36 +00:00
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{
|
2014-01-07 01:40:10 +00:00
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int ret = 0;
|
2005-04-16 22:20:36 +00:00
|
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struct cpufreq_policy *policy = data;
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struct cpufreq_frequency_table *table;
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unsigned int cpu = policy->cpu;
|
2013-01-14 13:23:03 +00:00
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if (val == CPUFREQ_UPDATE_POLICY_CPU) {
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cpufreq_stats_update_policy_cpu(policy);
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return 0;
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}
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2005-04-16 22:20:36 +00:00
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table = cpufreq_frequency_get_table(cpu);
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if (!table)
|
|
|
|
return 0;
|
2014-01-07 01:40:10 +00:00
|
|
|
|
|
|
|
if (val == CPUFREQ_CREATE_POLICY)
|
|
|
|
ret = cpufreq_stats_create_table(policy, table);
|
2014-01-07 01:40:12 +00:00
|
|
|
else if (val == CPUFREQ_REMOVE_POLICY)
|
|
|
|
__cpufreq_stats_free_table(policy);
|
2014-01-07 01:40:10 +00:00
|
|
|
|
|
|
|
return ret;
|
2005-04-16 22:20:36 +00:00
|
|
|
}
|
|
|
|
|
2009-01-18 06:49:04 +00:00
|
|
|
static int cpufreq_stat_notifier_trans(struct notifier_block *nb,
|
|
|
|
unsigned long val, void *data)
|
2005-04-16 22:20:36 +00:00
|
|
|
{
|
|
|
|
struct cpufreq_freqs *freq = data;
|
|
|
|
struct cpufreq_stats *stat;
|
|
|
|
int old_index, new_index;
|
|
|
|
|
|
|
|
if (val != CPUFREQ_POSTCHANGE)
|
|
|
|
return 0;
|
|
|
|
|
2008-03-25 22:06:53 +00:00
|
|
|
stat = per_cpu(cpufreq_stats_table, freq->cpu);
|
2005-04-16 22:20:36 +00:00
|
|
|
if (!stat)
|
|
|
|
return 0;
|
2006-12-19 20:58:55 +00:00
|
|
|
|
2008-04-27 20:46:56 +00:00
|
|
|
old_index = stat->last_index;
|
2005-04-16 22:20:36 +00:00
|
|
|
new_index = freq_table_get_index(stat, freq->new);
|
|
|
|
|
[CPUFREQ] Don't set stat->last_index to -1 if the pol->cur has incorrect value.
If the driver submitted an non-existing pol>cur value (say it
used the default initialized value of zero), when the cpufreq
stats tries to setup its initial values it incorrectly sets
stat->last_index to -1 (or 0xfffff...). And cpufreq_stats_update
tries to update at that index location and fails.
This can be caused by:
stat->last_index = freq_table_get_index(stat, policy->cur);
not finding the appropiate frequency in the table (b/c the policy->cur
is wrong) and we end up crashing. The fix however is
concentrated in the 'cpufreq_stats_update' as the last_index
(and old_index) are updated there. Which means it can reset
the last_index to -1 again and on the next iteration cause a crash.
Without this patch, the following crash is observed:
powernow-k8: Found 1 AMD Athlon(tm) 64 Processor 3700+ (1 cpu cores) (version 2.20.00)
powernow-k8: fid 0x2 (1000 MHz), vid 0x12
powernow-k8: fid 0xa (1800 MHz), vid 0xa
powernow-k8: fid 0xc (2000 MHz), vid 0x8
powernow-k8: fid 0xe (2200 MHz), vid 0x8
Marking TSC unstable due to cpufreq changes
powernow-k8: fid trans failed, fid 0x2, curr 0x0
BUG: unable to handle kernel paging request at ffff880807e07b78
IP: [<ffffffff81479163>] cpufreq_stats_update+0x46/0x5b
.. snip..
Pid: 1, comm: swapper Not tainted 3.0.0-rc2 #45 MICRO-STAR INTERNATIONAL CO., LTD MS-7094/MS-7094
..snip..
Call Trace:
[<ffffffff81479248>] cpufreq_stat_notifier_trans+0x48/0x7c
[<ffffffff81095d68>] notifier_call_chain+0x32/0x5e
[<ffffffff81095e6b>] __srcu_notifier_call_chain+0x47/0x63
[<ffffffff81095e96>] srcu_notifier_call_chain+0xf/0x11
[<ffffffff81477e7a>] cpufreq_notify_transition+0x111/0x134
[<ffffffff8147b0d4>] powernowk8_target+0x53b/0x617
[<ffffffff8147723a>] __cpufreq_driver_target+0x2e/0x30
[<ffffffff8147a127>] cpufreq_governor_dbs+0x339/0x356
[<ffffffff81477394>] __cpufreq_governor+0xa8/0xe9
[<ffffffff81477525>] __cpufreq_set_policy+0x132/0x13e
[<ffffffff8147848d>] cpufreq_add_dev_interface+0x272/0x28c
Reported-by: Tobias Diedrich <ranma+xen@tdiedrich.de>
Tested-by: Tobias Diedrich <ranma+xen@tdiedrich.de>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Dave Jones <davej@redhat.com>
2011-06-16 19:36:38 +00:00
|
|
|
/* We can't do stat->time_in_state[-1]= .. */
|
|
|
|
if (old_index == -1 || new_index == -1)
|
2005-04-16 22:20:36 +00:00
|
|
|
return 0;
|
|
|
|
|
[CPUFREQ] Don't set stat->last_index to -1 if the pol->cur has incorrect value.
If the driver submitted an non-existing pol>cur value (say it
used the default initialized value of zero), when the cpufreq
stats tries to setup its initial values it incorrectly sets
stat->last_index to -1 (or 0xfffff...). And cpufreq_stats_update
tries to update at that index location and fails.
This can be caused by:
stat->last_index = freq_table_get_index(stat, policy->cur);
not finding the appropiate frequency in the table (b/c the policy->cur
is wrong) and we end up crashing. The fix however is
concentrated in the 'cpufreq_stats_update' as the last_index
(and old_index) are updated there. Which means it can reset
the last_index to -1 again and on the next iteration cause a crash.
Without this patch, the following crash is observed:
powernow-k8: Found 1 AMD Athlon(tm) 64 Processor 3700+ (1 cpu cores) (version 2.20.00)
powernow-k8: fid 0x2 (1000 MHz), vid 0x12
powernow-k8: fid 0xa (1800 MHz), vid 0xa
powernow-k8: fid 0xc (2000 MHz), vid 0x8
powernow-k8: fid 0xe (2200 MHz), vid 0x8
Marking TSC unstable due to cpufreq changes
powernow-k8: fid trans failed, fid 0x2, curr 0x0
BUG: unable to handle kernel paging request at ffff880807e07b78
IP: [<ffffffff81479163>] cpufreq_stats_update+0x46/0x5b
.. snip..
Pid: 1, comm: swapper Not tainted 3.0.0-rc2 #45 MICRO-STAR INTERNATIONAL CO., LTD MS-7094/MS-7094
..snip..
Call Trace:
[<ffffffff81479248>] cpufreq_stat_notifier_trans+0x48/0x7c
[<ffffffff81095d68>] notifier_call_chain+0x32/0x5e
[<ffffffff81095e6b>] __srcu_notifier_call_chain+0x47/0x63
[<ffffffff81095e96>] srcu_notifier_call_chain+0xf/0x11
[<ffffffff81477e7a>] cpufreq_notify_transition+0x111/0x134
[<ffffffff8147b0d4>] powernowk8_target+0x53b/0x617
[<ffffffff8147723a>] __cpufreq_driver_target+0x2e/0x30
[<ffffffff8147a127>] cpufreq_governor_dbs+0x339/0x356
[<ffffffff81477394>] __cpufreq_governor+0xa8/0xe9
[<ffffffff81477525>] __cpufreq_set_policy+0x132/0x13e
[<ffffffff8147848d>] cpufreq_add_dev_interface+0x272/0x28c
Reported-by: Tobias Diedrich <ranma+xen@tdiedrich.de>
Tested-by: Tobias Diedrich <ranma+xen@tdiedrich.de>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Dave Jones <davej@redhat.com>
2011-06-16 19:36:38 +00:00
|
|
|
cpufreq_stats_update(freq->cpu);
|
|
|
|
|
|
|
|
if (old_index == new_index)
|
2006-12-19 20:58:55 +00:00
|
|
|
return 0;
|
|
|
|
|
2005-04-16 22:20:36 +00:00
|
|
|
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
|
|
|
|
};
|
|
|
|
|
2009-01-18 06:49:04 +00:00
|
|
|
static int __init cpufreq_stats_init(void)
|
2005-04-16 22:20:36 +00:00
|
|
|
{
|
|
|
|
int ret;
|
|
|
|
unsigned int cpu;
|
2005-10-30 22:59:54 +00:00
|
|
|
|
2005-04-16 22:20:36 +00:00
|
|
|
spin_lock_init(&cpufreq_stats_lock);
|
2009-01-18 06:49:04 +00:00
|
|
|
ret = cpufreq_register_notifier(¬ifier_policy_block,
|
|
|
|
CPUFREQ_POLICY_NOTIFIER);
|
|
|
|
if (ret)
|
2005-04-16 22:20:36 +00:00
|
|
|
return ret;
|
|
|
|
|
2009-01-18 06:49:04 +00:00
|
|
|
ret = cpufreq_register_notifier(¬ifier_trans_block,
|
|
|
|
CPUFREQ_TRANSITION_NOTIFIER);
|
|
|
|
if (ret) {
|
2005-04-16 22:20:36 +00:00
|
|
|
cpufreq_unregister_notifier(¬ifier_policy_block,
|
|
|
|
CPUFREQ_POLICY_NOTIFIER);
|
2012-12-14 23:22:02 +00:00
|
|
|
for_each_online_cpu(cpu)
|
|
|
|
cpufreq_stats_free_table(cpu);
|
2005-04-16 22:20:36 +00:00
|
|
|
return ret;
|
|
|
|
}
|
|
|
|
|
|
|
|
return 0;
|
|
|
|
}
|
2009-01-18 06:49:04 +00:00
|
|
|
static void __exit cpufreq_stats_exit(void)
|
2005-04-16 22:20:36 +00:00
|
|
|
{
|
|
|
|
unsigned int cpu;
|
2005-10-30 22:59:54 +00:00
|
|
|
|
2005-04-16 22:20:36 +00:00
|
|
|
cpufreq_unregister_notifier(¬ifier_policy_block,
|
|
|
|
CPUFREQ_POLICY_NOTIFIER);
|
|
|
|
cpufreq_unregister_notifier(¬ifier_trans_block,
|
|
|
|
CPUFREQ_TRANSITION_NOTIFIER);
|
2014-01-07 01:40:12 +00:00
|
|
|
for_each_online_cpu(cpu)
|
2007-10-02 20:28:15 +00:00
|
|
|
cpufreq_stats_free_table(cpu);
|
2005-04-16 22:20:36 +00:00
|
|
|
}
|
|
|
|
|
2009-01-18 06:49:04 +00:00
|
|
|
MODULE_AUTHOR("Zou Nan hai <nanhai.zou@intel.com>");
|
|
|
|
MODULE_DESCRIPTION("'cpufreq_stats' - A driver to export cpufreq stats "
|
2006-10-26 10:50:58 +00:00
|
|
|
"through sysfs filesystem");
|
2009-01-18 06:49:04 +00:00
|
|
|
MODULE_LICENSE("GPL");
|
2005-04-16 22:20:36 +00:00
|
|
|
|
|
|
|
module_init(cpufreq_stats_init);
|
|
|
|
module_exit(cpufreq_stats_exit);
|