From 8292c9e15c3b069459794a04f5e2cf0d5665ddc4 Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Wed, 24 Feb 2010 09:50:22 +0100 Subject: [PATCH] locking, semaphores: Annotate inner lock as raw There is no reason to have the spin_lock protecting the semaphore preemptible on -rt. Annotate it as a raw_spinlock. In mainline this change documents the low level nature of the lock - otherwise there's no functional difference. Lockdep and Sparse checking will work as usual. ( On rt this also solves lockdep complaining about the rt_mutex.wait_lock being not initialized. ) Signed-off-by: Thomas Gleixner Signed-off-by: Ingo Molnar --- include/linux/semaphore.h | 4 ++-- kernel/semaphore.c | 28 ++++++++++++++-------------- 2 files changed, 16 insertions(+), 16 deletions(-) diff --git a/include/linux/semaphore.h b/include/linux/semaphore.h index 39fa04966aa8..dc368b8ce215 100644 --- a/include/linux/semaphore.h +++ b/include/linux/semaphore.h @@ -14,14 +14,14 @@ /* Please don't access any members of this structure directly */ struct semaphore { - spinlock_t lock; + raw_spinlock_t lock; unsigned int count; struct list_head wait_list; }; #define __SEMAPHORE_INITIALIZER(name, n) \ { \ - .lock = __SPIN_LOCK_UNLOCKED((name).lock), \ + .lock = __RAW_SPIN_LOCK_UNLOCKED((name).lock), \ .count = n, \ .wait_list = LIST_HEAD_INIT((name).wait_list), \ } diff --git a/kernel/semaphore.c b/kernel/semaphore.c index 94a62c0d4ade..d831841e55a7 100644 --- a/kernel/semaphore.c +++ b/kernel/semaphore.c @@ -54,12 +54,12 @@ void down(struct semaphore *sem) { unsigned long flags; - spin_lock_irqsave(&sem->lock, flags); + raw_spin_lock_irqsave(&sem->lock, flags); if (likely(sem->count > 0)) sem->count--; else __down(sem); - spin_unlock_irqrestore(&sem->lock, flags); + raw_spin_unlock_irqrestore(&sem->lock, flags); } EXPORT_SYMBOL(down); @@ -77,12 +77,12 @@ int down_interruptible(struct semaphore *sem) unsigned long flags; int result = 0; - spin_lock_irqsave(&sem->lock, flags); + raw_spin_lock_irqsave(&sem->lock, flags); if (likely(sem->count > 0)) sem->count--; else result = __down_interruptible(sem); - spin_unlock_irqrestore(&sem->lock, flags); + raw_spin_unlock_irqrestore(&sem->lock, flags); return result; } @@ -103,12 +103,12 @@ int down_killable(struct semaphore *sem) unsigned long flags; int result = 0; - spin_lock_irqsave(&sem->lock, flags); + raw_spin_lock_irqsave(&sem->lock, flags); if (likely(sem->count > 0)) sem->count--; else result = __down_killable(sem); - spin_unlock_irqrestore(&sem->lock, flags); + raw_spin_unlock_irqrestore(&sem->lock, flags); return result; } @@ -132,11 +132,11 @@ int down_trylock(struct semaphore *sem) unsigned long flags; int count; - spin_lock_irqsave(&sem->lock, flags); + raw_spin_lock_irqsave(&sem->lock, flags); count = sem->count - 1; if (likely(count >= 0)) sem->count = count; - spin_unlock_irqrestore(&sem->lock, flags); + raw_spin_unlock_irqrestore(&sem->lock, flags); return (count < 0); } @@ -157,12 +157,12 @@ int down_timeout(struct semaphore *sem, long jiffies) unsigned long flags; int result = 0; - spin_lock_irqsave(&sem->lock, flags); + raw_spin_lock_irqsave(&sem->lock, flags); if (likely(sem->count > 0)) sem->count--; else result = __down_timeout(sem, jiffies); - spin_unlock_irqrestore(&sem->lock, flags); + raw_spin_unlock_irqrestore(&sem->lock, flags); return result; } @@ -179,12 +179,12 @@ void up(struct semaphore *sem) { unsigned long flags; - spin_lock_irqsave(&sem->lock, flags); + raw_spin_lock_irqsave(&sem->lock, flags); if (likely(list_empty(&sem->wait_list))) sem->count++; else __up(sem); - spin_unlock_irqrestore(&sem->lock, flags); + raw_spin_unlock_irqrestore(&sem->lock, flags); } EXPORT_SYMBOL(up); @@ -217,9 +217,9 @@ static inline int __sched __down_common(struct semaphore *sem, long state, if (timeout <= 0) goto timed_out; __set_task_state(task, state); - spin_unlock_irq(&sem->lock); + raw_spin_unlock_irq(&sem->lock); timeout = schedule_timeout(timeout); - spin_lock_irq(&sem->lock); + raw_spin_lock_irq(&sem->lock); if (waiter.up) return 0; } -- 2.30.2