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author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /include/asm-arm26/semaphore.h | |
download | op-kernel-dev-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.zip op-kernel-dev-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.gz |
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'include/asm-arm26/semaphore.h')
-rw-r--r-- | include/asm-arm26/semaphore.h | 103 |
1 files changed, 103 insertions, 0 deletions
diff --git a/include/asm-arm26/semaphore.h b/include/asm-arm26/semaphore.h new file mode 100644 index 0000000..c1b6a1e --- /dev/null +++ b/include/asm-arm26/semaphore.h @@ -0,0 +1,103 @@ +/* + * linux/include/asm-arm/semaphore.h + */ +#ifndef __ASM_ARM_SEMAPHORE_H +#define __ASM_ARM_SEMAPHORE_H + +#include <linux/linkage.h> +#include <linux/spinlock.h> +#include <linux/wait.h> +#include <linux/rwsem.h> + +#include <asm/atomic.h> +#include <asm/locks.h> + +struct semaphore { + atomic_t count; + int sleepers; + wait_queue_head_t wait; +}; + +#define __SEMAPHORE_INIT(name, n) \ +{ \ + .count = ATOMIC_INIT(n), \ + .sleepers = 0, \ + .wait = __WAIT_QUEUE_HEAD_INITIALIZER((name).wait), \ +} + +#define __MUTEX_INITIALIZER(name) \ + __SEMAPHORE_INIT(name,1) + +#define __DECLARE_SEMAPHORE_GENERIC(name,count) \ + struct semaphore name = __SEMAPHORE_INIT(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) +{ + 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); +} + +/* + * special register calling convention + */ +asmlinkage void __down_failed(void); +asmlinkage int __down_interruptible_failed(void); +asmlinkage int __down_trylock_failed(void); +asmlinkage void __up_wakeup(void); + +extern void __down(struct semaphore * sem); +extern int __down_interruptible(struct semaphore * sem); +extern int __down_trylock(struct semaphore * sem); +extern void __up(struct semaphore * sem); + +/* + * This is ugly, but we want the default case to fall through. + * "__down" is the actual routine that waits... + */ +static inline void down(struct semaphore * sem) +{ + might_sleep(); + __down_op(sem, __down_failed); +} + +/* + * This is ugly, but we want the default case to fall through. + * "__down_interruptible" is the actual routine that waits... + */ +static inline int down_interruptible (struct semaphore * sem) +{ + might_sleep(); + return __down_op_ret(sem, __down_interruptible_failed); +} + +static inline int down_trylock(struct semaphore *sem) +{ + return __down_op_ret(sem, __down_trylock_failed); +} + +/* + * 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) +{ + __up_op(sem, __up_wakeup); +} + +#endif |