cpufreq: conservative: call dbs_check_cpu only when necessary

Modify conservative timer to not resample CPU utilization if recently
sampled from another SW coordinated core.

Signed-off-by: Fabio Baltieri <fabio.baltieri@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This commit is contained in:
Fabio Baltieri 2012-12-27 14:55:41 +00:00 committed by Rafael J. Wysocki
parent da53d61e21
commit 66df2a01df
1 changed files with 41 additions and 6 deletions

View File

@ -111,22 +111,57 @@ static void cs_check_cpu(int cpu, unsigned int load)
}
}
static void cs_dbs_timer(struct work_struct *work)
static void cs_timer_update(struct cs_cpu_dbs_info_s *dbs_info, bool sample,
struct delayed_work *dw)
{
struct cs_cpu_dbs_info_s *dbs_info = container_of(work,
struct cs_cpu_dbs_info_s, cdbs.work.work);
unsigned int cpu = dbs_info->cdbs.cpu;
int delay = delay_for_sampling_rate(cs_tuners.sampling_rate);
if (sample)
dbs_check_cpu(&cs_dbs_data, cpu);
schedule_delayed_work_on(smp_processor_id(), dw, delay);
}
static void cs_timer_coordinated(struct cs_cpu_dbs_info_s *dbs_info_local,
struct delayed_work *dw)
{
struct cs_cpu_dbs_info_s *dbs_info;
ktime_t time_now;
s64 delta_us;
bool sample = true;
/* use leader CPU's dbs_info */
dbs_info = &per_cpu(cs_cpu_dbs_info, dbs_info_local->cdbs.cpu);
mutex_lock(&dbs_info->cdbs.timer_mutex);
dbs_check_cpu(&cs_dbs_data, cpu);
time_now = ktime_get();
delta_us = ktime_us_delta(time_now, dbs_info->cdbs.time_stamp);
schedule_delayed_work_on(smp_processor_id(), &dbs_info->cdbs.work,
delay);
/* Do nothing if we recently have sampled */
if (delta_us < (s64)(cs_tuners.sampling_rate / 2))
sample = false;
else
dbs_info->cdbs.time_stamp = time_now;
cs_timer_update(dbs_info, sample, dw);
mutex_unlock(&dbs_info->cdbs.timer_mutex);
}
static void cs_dbs_timer(struct work_struct *work)
{
struct delayed_work *dw = to_delayed_work(work);
struct cs_cpu_dbs_info_s *dbs_info = container_of(work,
struct cs_cpu_dbs_info_s, cdbs.work.work);
if (dbs_sw_coordinated_cpus(&dbs_info->cdbs)) {
cs_timer_coordinated(dbs_info, dw);
} else {
mutex_lock(&dbs_info->cdbs.timer_mutex);
cs_timer_update(dbs_info, true, dw);
mutex_unlock(&dbs_info->cdbs.timer_mutex);
}
}
static int dbs_cpufreq_notifier(struct notifier_block *nb, unsigned long val,
void *data)
{