/*
* Generic idle loop implementation
*/
static void cpu_idle_loop(void)
{
while (1) {
tick_nohz_idle_enter();
while (!need_resched()) {
check_pgt_cache();
rmb();
if (cpu_is_offline(smp_processor_id()))
arch_cpu_idle_dead();
local_irq_disable();
arch_cpu_idle_enter();
/*
* In poll mode we reenable interrupts and spin.
*
* Also if we detected in the wakeup from idle
* path that the tick broadcast device expired
* for us, we don't want to go deep idle as we
* know that the IPI is going to arrive right
* away
*/
if (cpu_idle_force_poll || tick_check_broadcast_expired()) {
cpu_idle_poll();
} else {
current_clr_polling();
if (!need_resched()) {
stop_critical_timings();
rcu_idle_enter();
arch_cpu_idle();
WARN_ON_ONCE(irqs_disabled());
rcu_idle_exit();
start_critical_timings();
} else {
local_irq_enable();
}
current_set_polling();
}
arch_cpu_idle_exit();
}
tick_nohz_idle_exit();
schedule_preempt_disabled();
}
}
static int poll_idle(struct cpuidle_device *dev,
struct cpuidle_driver *drv, int index)
{
ktime_t t1, t2;
s64 diff;
t1 = ktime_get();
local_irq_enable();
if (!current_set_polling_and_test()) {
while (!need_resched())
cpu_relax();
}
current_clr_polling();
t2 = ktime_get();
diff = ktime_to_us(ktime_sub(t2, t1));
if (diff > INT_MAX)
diff = INT_MAX;
dev->last_residency = (int) diff;
return index;
}
