[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>
diff --git a/drivers/cpufreq/cpufreq_conservative.c b/drivers/cpufreq/cpufreq_conservative.c
index 4bd33ce..57d02e9 100644
--- a/drivers/cpufreq/cpufreq_conservative.c
+++ b/drivers/cpufreq/cpufreq_conservative.c
@@ -116,6 +116,27 @@
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 @@
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 @@
* 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;