Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit dc775dd8 authored by Thomas Gleixner's avatar Thomas Gleixner
Browse files

sh: Use generic idle loop 



Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Paul McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Reviewed-by: default avatarCc: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Cc: Magnus Damm <magnus.damm@gmail.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Link: http://lkml.kernel.org/r/20130321215235.216323644@linutronix.de


Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
parent 99444202

arch/sh/Kconfig

+2 −0
Original line number Diff line number Diff line
@@ -33,6 +33,8 @@ config SUPERH 
	select GENERIC_ATOMIC64

	select GENERIC_IRQ_SHOW

	select GENERIC_SMP_IDLE_THREAD

	select GENERIC_IDLE_LOOP

	select GENERIC_IDLE_POLL_SETUP

	select GENERIC_CLOCKEVENTS

	select GENERIC_CMOS_UPDATE if SH_SH03 || SH_DREAMCAST

	select GENERIC_STRNCPY_FROM_USER

arch/sh/kernel/idle.c

+11 −90
Original line number Diff line number Diff line
@@ -24,98 +24,24 @@ 


static void (*sh_idle)(void);



static int hlt_counter;



static int __init nohlt_setup(char *__unused)

{

	hlt_counter = 1;

	return 1;

}

__setup("nohlt", nohlt_setup);



static int __init hlt_setup(char *__unused)

{

	hlt_counter = 0;

	return 1;

}

__setup("hlt", hlt_setup);



static inline int hlt_works(void)

{

	return !hlt_counter;

}



/*

 * On SMP it's slightly faster (but much more power-consuming!)

 * to poll the ->work.need_resched flag instead of waiting for the

 * cross-CPU IPI to arrive. Use this option with caution.

 */

static void poll_idle(void)

{

	local_irq_enable();

	while (!need_resched())

		cpu_relax();

}



void default_idle(void)

{

	if (hlt_works()) {

		clear_thread_flag(TIF_POLLING_NRFLAG);

		smp_mb__after_clear_bit();



	set_bl_bit();

		if (!need_resched()) {

	local_irq_enable();

	/* Isn't this racy ? */

	cpu_sleep();

		} else

			local_irq_enable();



		set_thread_flag(TIF_POLLING_NRFLAG);

	clear_bl_bit();

	} else

		poll_idle();

}



/*

 * The idle thread. There's no useful work to be done, so just try to conserve

 * power and have a low exit latency (ie sit in a loop waiting for somebody to

 * say that they'd like to reschedule)

 */

void cpu_idle(void)

void arch_cpu_idle_dead(void)

{

	unsigned int cpu = smp_processor_id();



	set_thread_flag(TIF_POLLING_NRFLAG);



	/* endless idle loop with no priority at all */

	while (1) {

		tick_nohz_idle_enter();

		rcu_idle_enter();



		while (!need_resched()) {

			check_pgt_cache();

			rmb();



			if (cpu_is_offline(cpu))

	play_dead();

}



			local_irq_disable();

			/* Don't trace irqs off for idle */

			stop_critical_timings();

void arch_cpu_idle(void)

{

	if (cpuidle_idle_call())

		sh_idle();

			/*

			 * Sanity check to ensure that sh_idle() returns

			 * with IRQs enabled

			 */

			WARN_ON(irqs_disabled());

			start_critical_timings();

		}



		rcu_idle_exit();

		tick_nohz_idle_exit();

		schedule_preempt_disabled();

	}

}



void __init select_idle_routine(void)
@@ -123,13 +49,8 @@ void __init select_idle_routine(void) 
	/*

	 * If a platform has set its own idle routine, leave it alone.

	 */

	if (sh_idle)

		return;



	if (hlt_works())

	if (!sh_idle)

		sh_idle = default_idle;

	else

		sh_idle = poll_idle;

}



void stop_this_cpu(void *unused)

arch/sh/kernel/smp.c

+1 −1
Original line number Diff line number Diff line
@@ -203,7 +203,7 @@ asmlinkage void __cpuinit start_secondary(void) 
	set_cpu_online(cpu, true);

	per_cpu(cpu_state, cpu) = CPU_ONLINE;



	cpu_idle();

	cpu_startup_entry(CPUHP_ONLINE);

}



extern struct {