| From 1020b7e31c11a7adab9d2e7e793287fff186a315 Mon Sep 17 00:00:00 2001 |
| From: Ingo Molnar <mingo@elte.hu> |
| Date: Fri, 3 Jul 2009 08:30:20 -0500 |
| Subject: [PATCH 109/262] timers: preempt-rt support |
| |
| Signed-off-by: Ingo Molnar <mingo@elte.hu> |
| Signed-off-by: Thomas Gleixner <tglx@linutronix.de> |
| --- |
| kernel/timer.c | 18 +++++++++++++++++- |
| 1 file changed, 17 insertions(+), 1 deletion(-) |
| |
| diff --git a/kernel/timer.c b/kernel/timer.c |
| index d7ad9d0..05cee31 100644 |
| --- a/kernel/timer.c |
| +++ b/kernel/timer.c |
| @@ -1344,6 +1344,22 @@ unsigned long get_next_timer_interrupt(unsigned long now) |
| */ |
| if (cpu_is_offline(smp_processor_id())) |
| return now + NEXT_TIMER_MAX_DELTA; |
| + |
| +#ifdef CONFIG_PREEMPT_RT_FULL |
| + /* |
| + * On PREEMPT_RT we cannot sleep here. If the trylock does not |
| + * succeed then we return the worst-case 'expires in 1 tick' |
| + * value: |
| + */ |
| + if (spin_trylock(&base->lock)) { |
| + if (time_before_eq(base->next_timer, base->timer_jiffies)) |
| + base->next_timer = __next_timer_interrupt(base); |
| + expires = base->next_timer; |
| + spin_unlock(&base->lock); |
| + } else { |
| + expires = now + 1; |
| + } |
| +#else |
| spin_lock(&base->lock); |
| if (time_before_eq(base->next_timer, base->timer_jiffies)) |
| base->next_timer = __next_timer_interrupt(base); |
| @@ -1352,7 +1368,7 @@ unsigned long get_next_timer_interrupt(unsigned long now) |
| |
| if (time_before_eq(expires, now)) |
| return now; |
| - |
| +#endif |
| return cmp_next_hrtimer_event(now, expires); |
| } |
| #endif |
| -- |
| 1.7.10.4 |
| |
