From 59b62bae6e0cd7be660a38a8b93e873fec85e078 Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Sun, 17 Jul 2011 22:08:38 +0200 Subject: [182/256] timer-handle-idle-trylock-in-get-next-timer-irq.patch Signed-off-by: Thomas Gleixner --- include/linux/spinlock_rt.h | 12 +++++++++++- kernel/rtmutex.c | 7 +------ kernel/timer.c | 7 ++++--- 3 files changed, 16 insertions(+), 10 deletions(-) diff --git a/include/linux/spinlock_rt.h b/include/linux/spinlock_rt.h index 205ca95..3b555b4 100644 --- a/include/linux/spinlock_rt.h +++ b/include/linux/spinlock_rt.h @@ -51,7 +51,17 @@ extern void __lockfunc __rt_spin_unlock(struct rt_mutex *lock); #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) \ diff --git a/kernel/rtmutex.c b/kernel/rtmutex.c index f9baaae..921c90b 100644 --- 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); diff --git a/kernel/timer.c b/kernel/timer.c index cc2588b..f6f2958 100644 --- a/kernel/timer.c +++ b/kernel/timer.c @@ -1373,13 +1373,14 @@ unsigned long get_next_timer_interrupt(unsigned long now) /* * 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)) { 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); + rt_spin_unlock(&base->lock); } else { expires = now + 1; }