| Subject: timer-handle-idle-trylock-in-get-next-timer-irq.patch |
| From: Thomas Gleixner <tglx@linutronix.de> |
| Date: Sun, 17 Jul 2011 22:08:38 +0200 |
| |
| Signed-off-by: Thomas Gleixner <tglx@linutronix.de> |
| --- |
| include/linux/spinlock_rt.h | 12 +++++++++++- |
| kernel/rtmutex.c | 7 +------ |
| kernel/timer.c | 9 +++++++-- |
| 3 files changed, 19 insertions(+), 9 deletions(-) |
| |
| --- a/include/linux/spinlock_rt.h |
| +++ b/include/linux/spinlock_rt.h |
| @@ -53,7 +53,17 @@ extern void __lockfunc __rt_spin_unlock( |
| |
| #define spin_lock_irq(lock) spin_lock(lock) |
| |
| -#define spin_trylock(lock) __cond_lock(lock, rt_spin_trylock(lock)) |
| +#define spin_do_trylock(lock) __cond_lock(lock, rt_spin_trylock(lock)) |
| + |
| +#define spin_trylock(lock) \ |
| +({ \ |
| + int __locked; \ |
| + migrate_disable(); \ |
| + __locked = spin_do_trylock(lock); \ |
| + if (!__locked) \ |
| + migrate_enable(); \ |
| + __locked; \ |
| +}) |
| |
| #ifdef CONFIG_LOCKDEP |
| # define spin_lock_nested(lock, subclass) \ |
| --- a/kernel/rtmutex.c |
| +++ b/kernel/rtmutex.c |
| @@ -861,15 +861,10 @@ EXPORT_SYMBOL(rt_spin_unlock_wait); |
| |
| int __lockfunc rt_spin_trylock(spinlock_t *lock) |
| { |
| - int ret; |
| + int ret = rt_mutex_trylock(&lock->lock); |
| |
| - migrate_disable(); |
| - ret = rt_mutex_trylock(&lock->lock); |
| if (ret) |
| spin_acquire(&lock->dep_map, 0, 1, _RET_IP_); |
| - else |
| - migrate_enable(); |
| - |
| return ret; |
| } |
| EXPORT_SYMBOL(rt_spin_trylock); |
| --- a/kernel/timer.c |
| +++ b/kernel/timer.c |
| @@ -1382,9 +1382,10 @@ unsigned long get_next_timer_interrupt(u |
| /* |
| * On PREEMPT_RT we cannot sleep here. If the trylock does not |
| * succeed then we return the worst-case 'expires in 1 tick' |
| - * value: |
| + * value. We use the rt functions here directly to avoid a |
| + * migrate_disable() call. |
| */ |
| - if (!spin_trylock(&base->lock)) |
| + if (!spin_do_trylock(&base->lock)) |
| return now + 1; |
| #else |
| spin_lock(&base->lock); |
| @@ -1394,7 +1395,11 @@ unsigned long get_next_timer_interrupt(u |
| base->next_timer = __next_timer_interrupt(base); |
| expires = base->next_timer; |
| } |
| +#ifdef CONFIG_PREEMPT_RT_FULL |
| + rt_spin_unlock(&base->lock); |
| +#else |
| spin_unlock(&base->lock); |
| +#endif |
| |
| if (time_before_eq(expires, now)) |
| return now; |