From 64ac24e738823161693bf791f87adc802cf529ff Mon Sep 17 00:00:00 2001 From: Matthew Wilcox Date: Fri, 7 Mar 2008 21:55:58 -0500 Subject: Generic semaphore implementation Semaphores are no longer performance-critical, so a generic C implementation is better for maintainability, debuggability and extensibility. Thanks to Peter Zijlstra for fixing the lockdep warning. Thanks to Harvey Harrison for pointing out that the unlikely() was unnecessary. Signed-off-by: Matthew Wilcox Acked-by: Ingo Molnar --- include/asm-blackfin/semaphore-helper.h | 82 --------------------------------- 1 file changed, 82 deletions(-) delete mode 100644 include/asm-blackfin/semaphore-helper.h (limited to 'include/asm-blackfin/semaphore-helper.h') diff --git a/include/asm-blackfin/semaphore-helper.h b/include/asm-blackfin/semaphore-helper.h deleted file mode 100644 index 9082b0dc3eb..00000000000 --- a/include/asm-blackfin/semaphore-helper.h +++ /dev/null @@ -1,82 +0,0 @@ -/* Based on M68K version, Lineo Inc. May 2001 */ - -#ifndef _BFIN_SEMAPHORE_HELPER_H -#define _BFIN_SEMAPHORE_HELPER_H - -/* - * SMP- and interrupt-safe semaphores helper functions. - * - * (C) Copyright 1996 Linus Torvalds - * - */ - -#include - -/* - * These two _must_ execute atomically wrt each other. - */ -static inline void wake_one_more(struct semaphore *sem) -{ - atomic_inc(&sem->waking); -} - -static inline int waking_non_zero(struct semaphore *sem) -{ - int ret; - unsigned long flags = 0; - - spin_lock_irqsave(&semaphore_wake_lock, flags); - ret = 0; - if (atomic_read(&sem->waking) > 0) { - atomic_dec(&sem->waking); - ret = 1; - } - spin_unlock_irqrestore(&semaphore_wake_lock, flags); - return ret; -} - -/* - * waking_non_zero_interruptible: - * 1 got the lock - * 0 go to sleep - * -EINTR interrupted - */ -static inline int waking_non_zero_interruptible(struct semaphore *sem, - struct task_struct *tsk) -{ - int ret = 0; - unsigned long flags = 0; - - spin_lock_irqsave(&semaphore_wake_lock, flags); - if (atomic_read(&sem->waking) > 0) { - atomic_dec(&sem->waking); - ret = 1; - } else if (signal_pending(tsk)) { - atomic_inc(&sem->count); - ret = -EINTR; - } - spin_unlock_irqrestore(&semaphore_wake_lock, flags); - return ret; -} - -/* - * waking_non_zero_trylock: - * 1 failed to lock - * 0 got the lock - */ -static inline int waking_non_zero_trylock(struct semaphore *sem) -{ - int ret = 1; - unsigned long flags = 0; - - spin_lock_irqsave(&semaphore_wake_lock, flags); - if (atomic_read(&sem->waking) > 0) { - atomic_dec(&sem->waking); - ret = 0; - } else - atomic_inc(&sem->count); - spin_unlock_irqrestore(&semaphore_wake_lock, flags); - return ret; -} - -#endif /* _BFIN_SEMAPHORE_HELPER_H */ -- cgit v1.2.3