diff options
Diffstat (limited to 'include/asm-m32r')
-rw-r--r-- | include/asm-m32r/semaphore.h | 145 |
1 files changed, 1 insertions, 144 deletions
diff --git a/include/asm-m32r/semaphore.h b/include/asm-m32r/semaphore.h index b5bf95a..d9b2034 100644 --- a/include/asm-m32r/semaphore.h +++ b/include/asm-m32r/semaphore.h @@ -1,144 +1 @@ -#ifndef _ASM_M32R_SEMAPHORE_H -#define _ASM_M32R_SEMAPHORE_H - -#include <linux/linkage.h> - -#ifdef __KERNEL__ - -/* - * SMP- and interrupt-safe semaphores.. - * - * Copyright (C) 1996 Linus Torvalds - * Copyright (C) 2004, 2006 Hirokazu Takata <takata at linux-m32r.org> - */ - -#include <linux/wait.h> -#include <linux/rwsem.h> -#include <asm/assembler.h> -#include <asm/system.h> -#include <asm/atomic.h> - -struct semaphore { - atomic_t count; - int sleepers; - wait_queue_head_t wait; -}; - -#define __SEMAPHORE_INITIALIZER(name, n) \ -{ \ - .count = ATOMIC_INIT(n), \ - .sleepers = 0, \ - .wait = __WAIT_QUEUE_HEAD_INITIALIZER((name).wait) \ -} - -#define __DECLARE_SEMAPHORE_GENERIC(name,count) \ - struct semaphore name = __SEMAPHORE_INITIALIZER(name,count) - -#define DECLARE_MUTEX(name) __DECLARE_SEMAPHORE_GENERIC(name,1) - -static inline void sema_init (struct semaphore *sem, int val) -{ -/* - * *sem = (struct semaphore)__SEMAPHORE_INITIALIZER((*sem),val); - * - * i'd rather use the more flexible initialization above, but sadly - * GCC 2.7.2.3 emits a bogus warning. EGCS doesnt. Oh well. - */ - atomic_set(&sem->count, val); - sem->sleepers = 0; - init_waitqueue_head(&sem->wait); -} - -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); -} - -asmlinkage void __down_failed(void /* special register calling convention */); -asmlinkage int __down_failed_interruptible(void /* params in registers */); -asmlinkage int __down_failed_trylock(void /* params in registers */); -asmlinkage void __up_wakeup(void /* special register calling convention */); - -asmlinkage void __down(struct semaphore * sem); -asmlinkage int __down_interruptible(struct semaphore * sem); -asmlinkage int __down_trylock(struct semaphore * sem); -asmlinkage void __up(struct semaphore * sem); - -/* - * Atomically decrement the semaphore's count. If it goes negative, - * block the calling thread in the TASK_UNINTERRUPTIBLE state. - */ -static inline void down(struct semaphore * sem) -{ - might_sleep(); - if (unlikely(atomic_dec_return(&sem->count) < 0)) - __down(sem); -} - -/* - * Interruptible try to acquire a semaphore. If we obtained - * it, return zero. If we were interrupted, returns -EINTR - */ -static inline int down_interruptible(struct semaphore * sem) -{ - int result = 0; - - might_sleep(); - if (unlikely(atomic_dec_return(&sem->count) < 0)) - result = __down_interruptible(sem); - - return result; -} - -/* - * Non-blockingly attempt to down() a semaphore. - * Returns zero if we acquired it - */ -static inline int down_trylock(struct semaphore * sem) -{ - unsigned long flags; - long count; - int result = 0; - - local_irq_save(flags); - __asm__ __volatile__ ( - "# down_trylock \n\t" - DCACHE_CLEAR("%0", "r4", "%1") - M32R_LOCK" %0, @%1; \n\t" - "addi %0, #-1; \n\t" - M32R_UNLOCK" %0, @%1; \n\t" - : "=&r" (count) - : "r" (&sem->count) - : "memory" -#ifdef CONFIG_CHIP_M32700_TS1 - , "r4" -#endif /* CONFIG_CHIP_M32700_TS1 */ - ); - local_irq_restore(flags); - - if (unlikely(count < 0)) - result = __down_trylock(sem); - - return result; -} - -/* - * Note! This is subtle. We jump to wake people up only if - * the semaphore was negative (== somebody was waiting on it). - * The default case (no contention) will result in NO - * jumps for both down() and up(). - */ -static inline void up(struct semaphore * sem) -{ - if (unlikely(atomic_inc_return(&sem->count) <= 0)) - __up(sem); -} - -#endif /* __KERNEL__ */ - -#endif /* _ASM_M32R_SEMAPHORE_H */ +#include <linux/semaphore.h> |