Re: [PATCH V3 3/6] sched: idle: Get the next timer event and pass it the cpuidle framework

On Fri, Nov 07, 2014 at 03:31:24PM +0100, Daniel Lezcano wrote:

static void cpu_idle_loop(void) {

• unsigned int latency_req;

• unsigned int latency_req, next_timer_event;

while (1) { /* @@ -221,6 +222,9 @@ static void cpu_idle_loop(void) latency_req = pm_qos_request(PM_QOS_CPU_DMA_LATENCY);

• 	next_timer_event =
  

• 		ktime_to_us(tick_nohz_get_sleep_length());
  

• /*
   * In poll mode we reenable interrupts and spin.
   *
  

@@ -238,7 +242,8 @@ static void cpu_idle_loop(void) tick_check_broadcast_expired()) cpu_idle_poll(); else

• 		cpuidle_idle_call(latency_req);
  

• 		cpuidle_idle_call(latency_req,
  

• 				  next_timer_event);
  

arch_cpu_idle_exit(); }

Why do we want to query the next timer in the poll case? Afaict the other patches don't make use of this either.