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>

1 files changed, 1 insertions, 34 deletions

diff --git a/drivers/thermal/intel_powerclamp.c b/drivers/thermal/intel_powerclamp.c
index c99af71c0ae7..6d93f1d65dba 100644
--- 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);