diff options
| -rw-r--r-- | kernel/sched/cpufreq_schedutil.c | 34 |
1 files changed, 26 insertions, 8 deletions
diff --git a/kernel/sched/cpufreq_schedutil.c b/kernel/sched/cpufreq_schedutil.c index caf435c14a52..178946e36393 100644 --- a/kernel/sched/cpufreq_schedutil.c +++ b/kernel/sched/cpufreq_schedutil.c @@ -92,9 +92,6 @@ static bool sugov_should_update_freq(struct sugov_policy *sg_policy, u64 time) !cpufreq_this_cpu_can_update(sg_policy->policy)) return false; - if (sg_policy->work_in_progress) - return false; - if (unlikely(sg_policy->need_freq_update)) return true; @@ -121,7 +118,7 @@ static void sugov_update_commit(struct sugov_policy *sg_policy, u64 time, policy->cur = next_freq; trace_cpu_frequency(next_freq, smp_processor_id()); - } else { + } else if (!sg_policy->work_in_progress) { sg_policy->work_in_progress = true; irq_work_queue(&sg_policy->irq_work); } @@ -366,6 +363,13 @@ static void sugov_update_single(struct update_util_data *hook, u64 time, ignore_dl_rate_limit(sg_cpu, sg_policy); + /* + * For slow-switch systems, single policy requests can't run at the + * moment if update is in progress, unless we acquire update_lock. + */ + if (sg_policy->work_in_progress) + return; + if (!sugov_should_update_freq(sg_policy, time)) return; @@ -440,13 +444,27 @@ sugov_update_shared(struct update_util_data *hook, u64 time, unsigned int flags) static void sugov_work(struct kthread_work *work) { struct sugov_policy *sg_policy = container_of(work, struct sugov_policy, work); + unsigned int freq; + unsigned long flags; + + /* + * Hold sg_policy->update_lock shortly to handle the case where: + * incase sg_policy->next_freq is read here, and then updated by + * sugov_update_shared just before work_in_progress is set to false + * here, we may miss queueing the new update. + * + * Note: If a work was queued after the update_lock is released, + * sugov_work will just be called again by kthread_work code; and the + * request will be proceed before the sugov thread sleeps. + */ + raw_spin_lock_irqsave(&sg_policy->update_lock, flags); + freq = sg_policy->next_freq; + sg_policy->work_in_progress = false; + raw_spin_unlock_irqrestore(&sg_policy->update_lock, flags); mutex_lock(&sg_policy->work_lock); - __cpufreq_driver_target(sg_policy->policy, sg_policy->next_freq, - CPUFREQ_RELATION_L); + __cpufreq_driver_target(sg_policy->policy, freq, CPUFREQ_RELATION_L); mutex_unlock(&sg_policy->work_lock); - - sg_policy->work_in_progress = false; } static void sugov_irq_work(struct irq_work *irq_work) |