From 2ea83398b75309d8fdc999c4bb252e72d7e4fd9d Mon Sep 17 00:00:00 2001 From: Russell King Date: Mon, 27 Jun 2005 14:04:05 +0100 Subject: [PATCH] [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: Russell King --- arch/arm/kernel/process.c | 5 ++++- arch/arm/kernel/time.c | 10 +++++++--- include/asm-arm/mach/time.h | 2 ++ 3 files changed, 13 insertions(+), 4 deletions(-) diff --git a/arch/arm/kernel/process.c b/arch/arm/kernel/process.c index 8f146a4b47..bbea636ff6 100644 --- a/arch/arm/kernel/process.c +++ b/arch/arm/kernel/process.c @@ -32,6 +32,7 @@ #include #include #include +#include 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(); } diff --git a/arch/arm/kernel/time.c b/arch/arm/kernel/time.c index 06054c9ba0..1b7fcd50c3 100644 --- a/arch/arm/kernel/time.c +++ b/arch/arm/kernel/time.c @@ -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) diff --git a/include/asm-arm/mach/time.h b/include/asm-arm/mach/time.h index 047980ad18..2cf279a440 100644 --- a/include/asm-arm/mach/time.h +++ b/include/asm-arm/mach/time.h @@ -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; -- 2.39.5