diff options
| -rw-r--r-- | drivers/cpufreq/cpufreq_interactive.c | 64 |
1 files changed, 54 insertions, 10 deletions
diff --git a/drivers/cpufreq/cpufreq_interactive.c b/drivers/cpufreq/cpufreq_interactive.c index 691923d6c86..90958fdd64d 100644 --- a/drivers/cpufreq/cpufreq_interactive.c +++ b/drivers/cpufreq/cpufreq_interactive.c @@ -189,6 +189,32 @@ static void cpufreq_interactive_timer_resched( spin_unlock_irqrestore(&pcpu->load_lock, flags); } +/* The caller shall take enable_sem write semaphore to avoid any timer race. + * The cpu_timer and cpu_slack_timer must be deactivated when calling this + * function. + */ +static void cpufreq_interactive_timer_start(int cpu) +{ + struct cpufreq_interactive_cpuinfo *pcpu = &per_cpu(cpuinfo, cpu); + unsigned long expires = jiffies + usecs_to_jiffies(timer_rate); + unsigned long flags; + + pcpu->cpu_timer.expires = expires; + add_timer_on(&pcpu->cpu_timer, cpu); + if (timer_slack_val >= 0 && pcpu->target_freq > pcpu->policy->min) { + expires += usecs_to_jiffies(timer_slack_val); + pcpu->cpu_slack_timer.expires = expires; + add_timer_on(&pcpu->cpu_slack_timer, cpu); + } + + spin_lock_irqsave(&pcpu->load_lock, flags); + pcpu->time_in_idle = + get_cpu_idle_time(cpu, &pcpu->time_in_idle_timestamp); + pcpu->cputime_speedadj = 0; + pcpu->cputime_speedadj_timestamp = pcpu->time_in_idle_timestamp; + spin_unlock_irqrestore(&pcpu->load_lock, flags); +} + static unsigned int freq_to_above_hispeed_delay(unsigned int freq) { int i; @@ -1058,8 +1084,6 @@ static int cpufreq_governor_interactive(struct cpufreq_policy *policy, hispeed_freq = policy->max; for_each_cpu(j, policy->cpus) { - unsigned long expires; - pcpu = &per_cpu(cpuinfo, j); pcpu->policy = policy; pcpu->target_freq = policy->cur; @@ -1070,14 +1094,7 @@ static int cpufreq_governor_interactive(struct cpufreq_policy *policy, pcpu->hispeed_validate_time = pcpu->floor_validate_time; down_write(&pcpu->enable_sem); - expires = jiffies + usecs_to_jiffies(timer_rate); - pcpu->cpu_timer.expires = expires; - add_timer_on(&pcpu->cpu_timer, j); - if (timer_slack_val >= 0) { - expires += usecs_to_jiffies(timer_slack_val); - pcpu->cpu_slack_timer.expires = expires; - add_timer_on(&pcpu->cpu_slack_timer, j); - } + cpufreq_interactive_timer_start(j); pcpu->governor_enabled = 1; up_write(&pcpu->enable_sem); } @@ -1136,6 +1153,33 @@ static int cpufreq_governor_interactive(struct cpufreq_policy *policy, else if (policy->min > policy->cur) __cpufreq_driver_target(policy, policy->min, CPUFREQ_RELATION_L); + for_each_cpu(j, policy->cpus) { + pcpu = &per_cpu(cpuinfo, j); + + /* hold write semaphore to avoid race */ + down_write(&pcpu->enable_sem); + if (pcpu->governor_enabled == 0) { + up_write(&pcpu->enable_sem); + continue; + } + + /* update target_freq firstly */ + if (policy->max < pcpu->target_freq) + pcpu->target_freq = policy->max; + else if (policy->min > pcpu->target_freq) + pcpu->target_freq = policy->min; + + /* Reschedule timer. + * Delete the timers, else the timer callback may + * return without re-arm the timer when failed + * acquire the semaphore. This race may cause timer + * stopped unexpectedly. + */ + del_timer_sync(&pcpu->cpu_timer); + del_timer_sync(&pcpu->cpu_slack_timer); + cpufreq_interactive_timer_start(j); + up_write(&pcpu->enable_sem); + } break; } return 0; |