Merge "cpufreq: Sync on thread migration optimizations" (ccf5f1f9) · Commits · e / devices / android_kernel_sony_msm8994

drivers/cpufreq/cpu-boost.c

+11 −0

Original line number	Diff line number	Diff line
		@@ -173,6 +173,17 @@ static int boost_mig_sync_thread(void *data)

		/* Force policy re-evaluation to trigger adjust notifier. */
		get_online_cpus();
		if (cpu_online(src_cpu))
		/*
		* Send an unchanged policy update to the source
		* CPU. Even though the policy isn't changed from
		* its existing boosted or non-boosted state
		* notifying the source CPU will let the governor
		* know a boost happened on another CPU and that it
		* should re-evaluate the frequency at the next timer
		* event without interference from a min sample time.
		*/
		cpufreq_update_policy(src_cpu);
		if (cpu_online(dest_cpu)) {
		cpufreq_update_policy(dest_cpu);
		queue_delayed_work_on(dest_cpu, cpu_boost_wq,

drivers/cpufreq/cpufreq_interactive.c

+46 −12

Original line number	Diff line number	Diff line
		@@ -55,8 +55,11 @@ struct cpufreq_interactive_cpuinfo {
		struct rw_semaphore enable_sem;
		int governor_enabled;
		int prev_load;
		bool limits_changed;
		};

		#define MIN_TIMER_JIFFIES 1UL

		static DEFINE_PER_CPU(struct cpufreq_interactive_cpuinfo, cpuinfo);

		/* realtime thread handles frequency scaling */
		@@ -174,11 +177,15 @@ static void cpufreq_interactive_timer_resched(
		* The cpu_timer and cpu_slack_timer must be deactivated when calling this
		* function.
		*/
		static void cpufreq_interactive_timer_start(int cpu)
		static void cpufreq_interactive_timer_start(int cpu, int time_override)
		{
		struct cpufreq_interactive_cpuinfo *pcpu = &per_cpu(cpuinfo, cpu);
		unsigned long expires = jiffies + usecs_to_jiffies(timer_rate);
		unsigned long flags;
		unsigned long expires;
		if (time_override)
		expires = jiffies + time_override;
		else
		expires = jiffies + usecs_to_jiffies(timer_rate);

		pcpu->cpu_timer.expires = expires;
		add_timer_on(&pcpu->cpu_timer, cpu);
		@@ -448,6 +455,10 @@ static void cpufreq_interactive_timer(unsigned long data)
		else
		mod_min_sample_time = min_sample_time;

		if (pcpu->limits_changed) {
		mod_min_sample_time = 0;
		pcpu->limits_changed = false;
		}
		if (new_freq < pcpu->floor_freq) {
		if (now - pcpu->floor_validate_time < mod_min_sample_time) {
		trace_cpufreq_interactive_notyet(
		@@ -1192,6 +1203,7 @@ static int cpufreq_governor_interactive(struct cpufreq_policy *policy,
		unsigned int j;
		struct cpufreq_interactive_cpuinfo *pcpu;
		struct cpufreq_frequency_table *freq_table;
		unsigned long expire_time;

		switch (event) {
		case CPUFREQ_GOV_START:
		@@ -1218,7 +1230,7 @@ static int cpufreq_governor_interactive(struct cpufreq_policy *policy,
		down_write(&pcpu->enable_sem);
		del_timer_sync(&pcpu->cpu_timer);
		del_timer_sync(&pcpu->cpu_slack_timer);
		cpufreq_interactive_timer_start(j);
		cpufreq_interactive_timer_start(j, 0);
		pcpu->governor_enabled = 1;
		up_write(&pcpu->enable_sem);
		}
		@@ -1296,18 +1308,40 @@ static int cpufreq_governor_interactive(struct cpufreq_policy *policy,
		/* 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.
		/*
		* Delete and reschedule timer.
		* Else the timer callback may return without
		* re-arming the timer when it fails to acquire
		* the semaphore. This race condition may cause the
		* timer to stop unexpectedly.
		*/
		del_timer_sync(&pcpu->cpu_timer);
		del_timer_sync(&pcpu->cpu_slack_timer);
		cpufreq_interactive_timer_start(j);
		if (policy->min >= pcpu->target_freq) {
		pcpu->target_freq = policy->min;
		/*
		* Reschedule timer.
		* The governor needs more time to evaluate
		* the load after changing policy parameters.
		*/
		cpufreq_interactive_timer_start(j, 0);
		} else {
		/*
		* Reschedule timer with variable duration.
		* No boost was applied so the governor
		* doesn't need extra time to evaluate load.
		* The timer can be set to fire quicker if it
		* was already going to expire soon.
		*/
		expire_time = pcpu->cpu_timer.expires - jiffies;
		expire_time = min(usecs_to_jiffies(timer_rate),
		expire_time);
		expire_time = max(MIN_TIMER_JIFFIES,
		expire_time);

		cpufreq_interactive_timer_start(j, expire_time);
		}
		pcpu->limits_changed = true;
		up_write(&pcpu->enable_sem);
		}
		break;