From: Viresh Kumar Date: Tue, 13 Oct 2015 08:09:01 +0000 (+0530) Subject: cpufreq: ondemand: Drop unnecessary locks from update_sampling_rate() X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=083701b13c79a908fb400dc24aaa80aad07ac462;p=linux-beck.git cpufreq: ondemand: Drop unnecessary locks from update_sampling_rate() '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 Signed-off-by: Viresh Kumar Signed-off-by: Rafael J. Wysocki --- diff --git a/drivers/cpufreq/cpufreq_ondemand.c b/drivers/cpufreq/cpufreq_ondemand.c index 1fa9088c84a8..03ac6ce54042 100644 --- a/drivers/cpufreq/cpufreq_ondemand.c +++ b/drivers/cpufreq/cpufreq_ondemand.c @@ -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); } }