thermal/intel_powerclamp: stop sched tick in forced idle

With the introduction of play_idle(), idle injection kthread can
go through the normal idle task processing to get correct accounting
and turn off scheduler tick when possible.

Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

diff --git a/drivers/thermal/intel_powerclamp.c b/drivers/thermal/intel_powerclamp.c
index c99af71c0ae78386f18e42536fa6b606b84bfa6d..6d93f1d65dbac28b85e90f537261ddc685406c00 100644 (file)
--- a/drivers/thermal/intel_powerclamp.c
+++ b/drivers/thermal/intel_powerclamp.c
@@ -92,7 +92,6 @@ struct powerclamp_worker_data {
        struct kthread_worker *worker;
        struct kthread_work balancing_work;
        struct kthread_delayed_work idle_injection_work;
-       struct timer_list wakeup_timer;
        unsigned int cpu;
        unsigned int count;
        unsigned int guard;
@@ -277,11 +276,6 @@ static u64 pkg_state_counter(void)
        return count;
 }
 
-static void noop_timer(unsigned long foo)
-{
-       /* empty... just the fact that we get the interrupt wakes us up */
-}
-
 static unsigned int get_compensation(int ratio)
 {
        unsigned int comp = 0;
@@ -431,7 +425,6 @@ static void clamp_balancing_func(struct kthread_work *work)
 static void clamp_idle_injection_func(struct kthread_work *work)
 {
        struct powerclamp_worker_data *w_data;
-       unsigned long target_jiffies;
 
        w_data = container_of(work, struct powerclamp_worker_data,
                              idle_injection_work.work);
@@ -452,31 +445,7 @@ static void clamp_idle_injection_func(struct kthread_work *work)
        if (should_skip)
                goto balance;
 
-       target_jiffies = jiffies + w_data->duration_jiffies;
-       mod_timer(&w_data->wakeup_timer, target_jiffies);
-       if (unlikely(local_softirq_pending()))
-               goto balance;
-       /*
-        * stop tick sched during idle time, interrupts are still
-        * allowed. thus jiffies are updated properly.
-        */
-       preempt_disable();
-       /* mwait until target jiffies is reached */
-       while (time_before(jiffies, target_jiffies)) {
-               unsigned long ecx = 1;
-               unsigned long eax = target_mwait;
-
-               /*
-                * REVISIT: may call enter_idle() to notify drivers who
-                * can save power during cpu idle. same for exit_idle()
-                */
-               local_touch_nmi();
-               stop_critical_timings();
-               mwait_idle_with_hints(eax, ecx);
-               start_critical_timings();
-               atomic_inc(&idle_wakeup_counter);
-       }
-       preempt_enable();
+       play_idle(jiffies_to_msecs(w_data->duration_jiffies));
 
 balance:
        if (clamping && w_data->clamping && cpu_online(w_data->cpu))
@@ -538,7 +507,6 @@ static void start_power_clamp_worker(unsigned long cpu)
        w_data->cpu = cpu;
        w_data->clamping = true;
        set_bit(cpu, cpu_clamping_mask);
-       setup_timer(&w_data->wakeup_timer, noop_timer, 0);
        sched_setscheduler(worker->task, SCHED_FIFO, &sparam);
        kthread_init_work(&w_data->balancing_work, clamp_balancing_func);
        kthread_init_delayed_work(&w_data->idle_injection_work,
@@ -570,7 +538,6 @@ static void stop_power_clamp_worker(unsigned long cpu)
         * a big deal. The balancing work is fast and destroy kthread
         * will wait for it.
         */
-       del_timer_sync(&w_data->wakeup_timer);
        clear_bit(w_data->cpu, cpu_clamping_mask);
        kthread_destroy_worker(w_data->worker);