Commit 2ea83398 authored by Russell King's avatar Russell King Committed by Russell King
Browse files

[PATCH] ARM: Add VST idle loop call 



This call allows the dynamic tick support to reprogram the timer
immediately before the CPU idles.

Signed-off-by: default avatarRussell King <rmk+kernel@arm.linux.org.uk>
parent 99bcc059

arch/arm/kernel/process.c

+4 −1
Original line number Diff line number Diff line
@@ -32,6 +32,7 @@ 
#include <asm/leds.h>

#include <asm/processor.h>

#include <asm/uaccess.h>

#include <asm/mach/time.h>



extern const char *processor_modes[];

extern void setup_mm_for_reboot(char mode);
@@ -85,8 +86,10 @@ EXPORT_SYMBOL(pm_power_off); 
void default_idle(void)

{

	local_irq_disable();

	if (!need_resched() && !hlt_counter)

	if (!need_resched() && !hlt_counter) {

		timer_dyn_reprogram();

		arch_idle();

	}

	local_irq_enable();

}

arch/arm/kernel/time.c

+7 −3
Original line number Diff line number Diff line
@@ -424,15 +424,19 @@ static int timer_dyn_tick_disable(void) 
	return ret;

}



/*

 * Reprogram the system timer for at least the calculated time interval.

 * This function should be called from the idle thread with IRQs disabled,

 * immediately before sleeping.

 */

void timer_dyn_reprogram(void)

{

	struct dyn_tick_timer *dyn_tick = system_timer->dyn_tick;

	unsigned long flags;



	write_seqlock_irqsave(&xtime_lock, flags);

	write_seqlock(&xtime_lock);

	if (dyn_tick->state & DYN_TICK_ENABLED)

		dyn_tick->reprogram(next_timer_interrupt() - jiffies);

	write_sequnlock_irqrestore(&xtime_lock, flags);

	write_sequnlock(&xtime_lock);

}



static ssize_t timer_show_dyn_tick(struct sys_device *dev, char *buf)

include/asm-arm/mach/time.h

+2 −0
Original line number Diff line number Diff line
@@ -60,6 +60,8 @@ struct dyn_tick_timer { 
};



void timer_dyn_reprogram(void);

#else

#define timer_dyn_reprogram()	do { } while (0)

#endif



extern struct sys_timer *system_timer;