diff options
Diffstat (limited to 'include/asm-mn10300/semaphore.h')
| -rw-r--r-- | include/asm-mn10300/semaphore.h | 170 |
1 files changed, 1 insertions, 169 deletions
diff --git a/include/asm-mn10300/semaphore.h b/include/asm-mn10300/semaphore.h index 5a9e1ad0b253..d9b2034ed1d2 100644 --- a/include/asm-mn10300/semaphore.h +++ b/include/asm-mn10300/semaphore.h @@ -1,169 +1 @@ -/* MN10300 Semaphores - * - * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved. - * Written by David Howells (dhowells@redhat.com) - * - * This program is free software; you can redistribute it and/or - * modify it under the terms of the GNU General Public Licence - * as published by the Free Software Foundation; either version - * 2 of the Licence, or (at your option) any later version. - */ -#ifndef _ASM_SEMAPHORE_H -#define _ASM_SEMAPHORE_H - -#ifndef __ASSEMBLY__ - -#include <linux/linkage.h> -#include <linux/wait.h> -#include <linux/spinlock.h> -#include <linux/rwsem.h> - -#define SEMAPHORE_DEBUG 0 - -/* - * the semaphore definition - * - if count is >0 then there are tokens available on the semaphore for down - * to collect - * - if count is <=0 then there are no spare tokens, and anyone that wants one - * must wait - * - if wait_list is not empty, then there are processes waiting for the - * semaphore - */ -struct semaphore { - atomic_t count; /* it's not really atomic, it's - * just that certain modules - * expect to be able to access - * it directly */ - spinlock_t wait_lock; - struct list_head wait_list; -#if SEMAPHORE_DEBUG - unsigned __magic; -#endif -}; - -#if SEMAPHORE_DEBUG -# define __SEM_DEBUG_INIT(name) , (long)&(name).__magic -#else -# define __SEM_DEBUG_INIT(name) -#endif - - -#define __SEMAPHORE_INITIALIZER(name, init_count) \ -{ \ - .count = ATOMIC_INIT(init_count), \ - .wait_lock = __SPIN_LOCK_UNLOCKED((name).wait_lock), \ - .wait_list = LIST_HEAD_INIT((name).wait_list) \ - __SEM_DEBUG_INIT(name) \ -} - -#define __DECLARE_SEMAPHORE_GENERIC(name,count) \ - struct semaphore name = __SEMAPHORE_INITIALIZER(name, count) - -#define DECLARE_MUTEX(name) __DECLARE_SEMAPHORE_GENERIC(name, 1) -#define DECLARE_MUTEX_LOCKED(name) __DECLARE_SEMAPHORE_GENERIC(name, 0) - -static inline void sema_init(struct semaphore *sem, int val) -{ - *sem = (struct semaphore) __SEMAPHORE_INITIALIZER(*sem, val); -} - -static inline void init_MUTEX(struct semaphore *sem) -{ - sema_init(sem, 1); -} - -static inline void init_MUTEX_LOCKED(struct semaphore *sem) -{ - sema_init(sem, 0); -} - -extern void __down(struct semaphore *sem, unsigned long flags); -extern int __down_interruptible(struct semaphore *sem, unsigned long flags); -extern void __up(struct semaphore *sem); - -static inline void down(struct semaphore *sem) -{ - unsigned long flags; - int count; - -#if SEMAPHORE_DEBUG - CHECK_MAGIC(sem->__magic); -#endif - - spin_lock_irqsave(&sem->wait_lock, flags); - count = atomic_read(&sem->count); - if (likely(count > 0)) { - atomic_set(&sem->count, count - 1); - spin_unlock_irqrestore(&sem->wait_lock, flags); - } else { - __down(sem, flags); - } -} - -static inline int down_interruptible(struct semaphore *sem) -{ - unsigned long flags; - int count, ret = 0; - -#if SEMAPHORE_DEBUG - CHECK_MAGIC(sem->__magic); -#endif - - spin_lock_irqsave(&sem->wait_lock, flags); - count = atomic_read(&sem->count); - if (likely(count > 0)) { - atomic_set(&sem->count, count - 1); - spin_unlock_irqrestore(&sem->wait_lock, flags); - } else { - ret = __down_interruptible(sem, flags); - } - return ret; -} - -/* - * non-blockingly attempt to down() a semaphore. - * - returns zero if we acquired it - */ -static inline int down_trylock(struct semaphore *sem) -{ - unsigned long flags; - int count, success = 0; - -#if SEMAPHORE_DEBUG - CHECK_MAGIC(sem->__magic); -#endif - - spin_lock_irqsave(&sem->wait_lock, flags); - count = atomic_read(&sem->count); - if (likely(count > 0)) { - atomic_set(&sem->count, count - 1); - success = 1; - } - spin_unlock_irqrestore(&sem->wait_lock, flags); - return !success; -} - -static inline void up(struct semaphore *sem) -{ - unsigned long flags; - -#if SEMAPHORE_DEBUG - CHECK_MAGIC(sem->__magic); -#endif - - spin_lock_irqsave(&sem->wait_lock, flags); - if (!list_empty(&sem->wait_list)) - __up(sem); - else - atomic_set(&sem->count, atomic_read(&sem->count) + 1); - spin_unlock_irqrestore(&sem->wait_lock, flags); -} - -static inline int sem_getcount(struct semaphore *sem) -{ - return atomic_read(&sem->count); -} - -#endif /* __ASSEMBLY__ */ - -#endif +#include <linux/semaphore.h> |