diff options
Diffstat (limited to 'kernel/idle.c')
| -rw-r--r-- | kernel/idle.c | 44 |
1 files changed, 34 insertions, 10 deletions
diff --git a/kernel/idle.c b/kernel/idle.c index b6e7d8f18..4f036cbcc 100644 --- a/kernel/idle.c +++ b/kernel/idle.c @@ -18,6 +18,15 @@ * state. */ s32_t _sys_idle_threshold_ticks = CONFIG_TICKLESS_IDLE_THRESH; + +#if defined(CONFIG_TICKLESS_KERNEL) +#define _must_enter_tickless_idle(ticks) (1) +#else +#define _must_enter_tickless_idle(ticks) \ + ((ticks == K_FOREVER) || (ticks >= _sys_idle_threshold_ticks)) +#endif +#else +#define _must_enter_tickless_idle(ticks) ((void)ticks, (0)) #endif /* CONFIG_TICKLESS_IDLE */ #ifdef CONFIG_SYS_POWER_MANAGEMENT @@ -54,18 +63,37 @@ static void set_kernel_idle_time_in_ticks(s32_t ticks) #define set_kernel_idle_time_in_ticks(x) do { } while (0) #endif -static void _sys_power_save_idle(s32_t ticks __unused) +static void _sys_power_save_idle(s32_t ticks) { -#if defined(CONFIG_TICKLESS_IDLE) - if ((ticks == K_FOREVER) || ticks >= _sys_idle_threshold_ticks) { +#ifdef CONFIG_TICKLESS_KERNEL + if (ticks != K_FOREVER) { + ticks -= _get_elapsed_program_time(); + if (!ticks) { + /* + * Timer has expired or about to expire + * No time for power saving operations + * + * Note that it will never be zero unless some time + * had elapsed since timer was last programmed. + */ + k_cpu_idle(); + return; + } + } +#endif + if (_must_enter_tickless_idle(ticks)) { /* * Stop generating system timer interrupts until it's time for * the next scheduled kernel timer to expire. */ + /* + * In the case of tickless kernel, timer driver should + * reprogram timer only if the currently programmed time + * duration is smaller than the idle time. + */ _timer_idle_enter(ticks); } -#endif /* CONFIG_TICKLESS_IDLE */ set_kernel_idle_time_in_ticks(ticks); #if (defined(CONFIG_SYS_POWER_LOW_POWER_STATE) || \ @@ -108,15 +136,11 @@ void _sys_power_save_idle_exit(s32_t ticks) _sys_soc_resume(); } #endif -#ifdef CONFIG_TICKLESS_IDLE - if ((ticks == K_FOREVER) || ticks >= _sys_idle_threshold_ticks) { - /* Resume normal periodic system timer interrupts */ + if (_must_enter_tickless_idle(ticks)) { + /* Resume normal periodic system timer interrupts */ _timer_idle_exit(); } -#else - ARG_UNUSED(ticks); -#endif /* CONFIG_TICKLESS_IDLE */ } |