diff options
Diffstat (limited to 'arch/sh/kernel/idle.c')
| -rw-r--r-- | arch/sh/kernel/idle.c | 127 | 
1 files changed, 14 insertions, 113 deletions
diff --git a/arch/sh/kernel/idle.c b/arch/sh/kernel/idle.c index 425d604e3a2..be616ee0cf8 100644 --- a/arch/sh/kernel/idle.c +++ b/arch/sh/kernel/idle.c @@ -16,104 +16,30 @@  #include <linux/thread_info.h>  #include <linux/irqflags.h>  #include <linux/smp.h> +#include <linux/atomic.h>  #include <asm/pgalloc.h> -#include <asm/system.h> -#include <asm/atomic.h>  #include <asm/smp.h> +#include <asm/bl_bit.h> -void (*pm_idle)(void) = NULL; +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) +void default_idle(void)  { +	set_bl_bit();  	local_irq_enable(); -	while (!need_resched()) -		cpu_relax(); +	/* Isn't this racy ? */ +	cpu_sleep(); +	clear_bl_bit();  } -void default_idle(void) +void arch_cpu_idle_dead(void)  { -	if (hlt_works()) { -		clear_thread_flag(TIF_POLLING_NRFLAG); -		smp_mb__after_clear_bit(); - -		set_bl_bit(); -		if (!need_resched()) { -			local_irq_enable(); -			cpu_sleep(); -		} else -			local_irq_enable(); - -		set_thread_flag(TIF_POLLING_NRFLAG); -		clear_bl_bit(); -	} else -		poll_idle(); +	play_dead();  } -/* - * 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(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_stop_sched_tick(1); - -		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(); -			pm_idle(); -			/* -			 * Sanity check to ensure that pm_idle() returns -			 * with IRQs enabled -			 */ -			WARN_ON(irqs_disabled()); -			start_critical_timings(); -		} - -		tick_nohz_restart_sched_tick(); -		preempt_enable_no_resched(); -		schedule(); -		preempt_disable(); -	} +	sh_idle();  }  void __init select_idle_routine(void) @@ -121,17 +47,8 @@ void __init select_idle_routine(void)  	/*  	 * If a platform has set its own idle routine, leave it alone.  	 */ -	if (pm_idle) -		return; - -	if (hlt_works()) -		pm_idle = default_idle; -	else -		pm_idle = poll_idle; -} - -static void do_nothing(void *unused) -{ +	if (!sh_idle) +		sh_idle = default_idle;  }  void stop_this_cpu(void *unused) @@ -142,19 +59,3 @@ void stop_this_cpu(void *unused)  	for (;;)  		cpu_sleep();  } - -/* - * cpu_idle_wait - Used to ensure that all the CPUs discard old value of - * pm_idle and update to new pm_idle value. Required while changing pm_idle - * handler on SMP systems. - * - * Caller must have changed pm_idle to the new value before the call. Old - * pm_idle value will not be used by any CPU after the return of this function. - */ -void cpu_idle_wait(void) -{ -	smp_mb(); -	/* kick all the CPUs so that they exit out of pm_idle */ -	smp_call_function(do_nothing, NULL, 1); -} -EXPORT_SYMBOL_GPL(cpu_idle_wait);  | 
