Techwizz/kernel-fxtec-pro1x
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity

cpufreq: ondemand: Drop unnecessary locks from update_sampling_rate()

Browse source 
'timer_mutex' is required to sync work-handlers of policy->cpus.
update_sampling_rate() is just canceling the works and queuing them
again. This isn't protecting anything at all in update_sampling_rate()
and is not gonna be of any use.

Even if a work-handler is already running for a CPU,
cancel_delayed_work_sync() will wait for it to finish.

Drop these unnecessary locks.

Reviewed-by: Preeti U Murthy <preeti@linux.vnet.ibm.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This commit is contained in:
Viresh Kumar 2015-10-13 13:39:01 +05:30 committed by Rafael J. Wysocki
parent 51443fbf3d
commit 083701b13c
1 changed files with 1 additions and 9 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

10
drivers/cpufreq/cpufreq_ondemand.c
View file

@ -267,27 +267,19 @@ static void update_sampling_rate(struct dbs_data *dbs_data,
dbs_info = &per_cpu(od_cpu_dbs_info, cpu);
cpufreq_cpu_put(policy);
mutex_lock(&dbs_info->cdbs.shared->timer_mutex);
if (!delayed_work_pending(&dbs_info->cdbs.dwork)) {
mutex_unlock(&dbs_info->cdbs.shared->timer_mutex);
if (!delayed_work_pending(&dbs_info->cdbs.dwork))
continue;
}
next_sampling = jiffies + usecs_to_jiffies(new_rate);
appointed_at = dbs_info->cdbs.dwork.timer.expires;
if (time_before(next_sampling, appointed_at)) {
mutex_unlock(&dbs_info->cdbs.shared->timer_mutex);
cancel_delayed_work_sync(&dbs_info->cdbs.dwork);
mutex_lock(&dbs_info->cdbs.shared->timer_mutex);
gov_queue_work(dbs_data, policy,
usecs_to_jiffies(new_rate), true);
}
mutex_unlock(&dbs_info->cdbs.shared->timer_mutex);
}
}