[CPUFREQ] Make cpufreq_conservative handle out-of-sync events properly

Make cpufreq_conservative handle out-of-sync events properly

Currently, the cpufreq_conservative governor doesn't get notified when the
actual frequency the cpu is running at differs from what cpufreq thought it
was. As a result the cpu may stay at the maximum frequency after a s2ram /
resume cycle even though the system is idle.

Signed-off-by: Elias Oltmanns <eo@nebensachen.de>
Signed-off-by: Dave Jones <davej@redhat.com>
This commit is contained in:
Elias Oltmanns 2007-10-22 09:50:13 +02:00 committed by Dave Jones
parent c5829cd07e
commit a8d7c3bc23

View File

@ -116,6 +116,27 @@ static inline unsigned int get_cpu_idle_time(unsigned int cpu)
return ret;
}
/* keep track of frequency transitions */
static int
dbs_cpufreq_notifier(struct notifier_block *nb, unsigned long val,
void *data)
{
struct cpufreq_freqs *freq = data;
struct cpu_dbs_info_s *this_dbs_info = &per_cpu(cpu_dbs_info,
freq->cpu);
if (!this_dbs_info->enable)
return 0;
this_dbs_info->requested_freq = freq->new;
return 0;
}
static struct notifier_block dbs_cpufreq_notifier_block = {
.notifier_call = dbs_cpufreq_notifier
};
/************************** sysfs interface ************************/
static ssize_t show_sampling_rate_max(struct cpufreq_policy *policy, char *buf)
{
@ -511,6 +532,9 @@ static int cpufreq_governor_dbs(struct cpufreq_policy *policy,
dbs_tuners_ins.sampling_rate = def_sampling_rate;
dbs_timer_init();
cpufreq_register_notifier(
&dbs_cpufreq_notifier_block,
CPUFREQ_TRANSITION_NOTIFIER);
}
mutex_unlock(&dbs_mutex);
@ -525,9 +549,13 @@ static int cpufreq_governor_dbs(struct cpufreq_policy *policy,
* Stop the timerschedule work, when this governor
* is used for first time
*/
if (dbs_enable == 0)
if (dbs_enable == 0) {
dbs_timer_exit();
cpufreq_unregister_notifier(
&dbs_cpufreq_notifier_block,
CPUFREQ_TRANSITION_NOTIFIER);
}
mutex_unlock(&dbs_mutex);
break;