Commit c8cc7d4d authored by Daniel Lezcano's avatar Daniel Lezcano Committed by Ingo Molnar
Browse files

sched/idle: Reorganize the idle loop 



Now that we have the main cpuidle function in idle.c, move some code from
the idle mainloop to this function for the sake of clarity.

That removes if then else indentation difficult to follow when looking at the
code. This patch does not change the current behavior.

Signed-off-by: default avatarDaniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: default avatarNicolas Pitre <nico@linaro.org>
Signed-off-by: default avatarPeter Zijlstra <peterz@infradead.org>
Cc: tglx@linutronix.de
Cc: rjw@rjwysocki.net
Cc: preeti@linux.vnet.ibm.com
Link: http://lkml.kernel.org/r/1393832934-11625-3-git-send-email-daniel.lezcano@linaro.org


Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
parent 30cdd69e

include/linux/cpuidle.h

+2 −0
Original line number Diff line number Diff line
@@ -180,6 +180,8 @@ static inline int cpuidle_enable_device(struct cpuidle_device *dev) 
{return -ENODEV; }

static inline void cpuidle_disable_device(struct cpuidle_device *dev) { }

static inline int cpuidle_play_dead(void) {return -ENODEV; }

static inline struct cpuidle_driver *cpuidle_get_cpu_driver(

	struct cpuidle_device *dev) {return NULL; }

#endif



#ifdef CONFIG_ARCH_NEEDS_CPU_IDLE_COUPLED

kernel/sched/idle.c

+15 −18
Original line number Diff line number Diff line
@@ -63,7 +63,6 @@ void __weak arch_cpu_idle(void) 
	local_irq_enable();

}



#ifdef CONFIG_CPU_IDLE

/**

 * cpuidle_idle_call - the main idle function

 *
@@ -77,9 +76,14 @@ static int cpuidle_idle_call(void) 
	int next_state, entered_state, ret;

	bool broadcast;



	stop_critical_timings();

	rcu_idle_enter();



	ret = cpuidle_enabled(drv, dev);

	if (ret < 0)

		return ret;

	if (ret < 0) {

		arch_cpu_idle();

		goto out;

	}



	/* ask the governor for the next state */

	next_state = cpuidle_select(drv, dev);
@@ -89,7 +93,7 @@ static int cpuidle_idle_call(void) 
		/* give the governor an opportunity to reflect on the outcome */

		cpuidle_reflect(dev, next_state);

		local_irq_enable();

		return 0;

		goto out;

	}



	broadcast = !!(drv->states[next_state].flags & CPUIDLE_FLAG_TIMER_STOP);
@@ -109,15 +113,15 @@ static int cpuidle_idle_call(void) 


	/* give the governor an opportunity to reflect on the outcome */

	cpuidle_reflect(dev, entered_state);

out:

	if (WARN_ON_ONCE(irqs_disabled()))

		local_irq_enable();



	rcu_idle_exit();

	start_critical_timings();



	return 0;

}

#else

static inline int cpuidle_idle_call(void)

{

	return -ENODEV;

}

#endif



/*

 * Generic idle loop implementation
@@ -150,14 +154,7 @@ static void cpu_idle_loop(void) 
				cpu_idle_poll();

			} else {

				if (!current_clr_polling_and_test()) {

					stop_critical_timings();

					rcu_idle_enter();

					if (cpuidle_idle_call())

						arch_cpu_idle();

					if (WARN_ON_ONCE(irqs_disabled()))

						local_irq_enable();

					rcu_idle_exit();

					start_critical_timings();

					cpuidle_idle_call();

				} else {

					local_irq_enable();

				}

CRA Git | Maintained and supported by SUSTech CRA and CCSE