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author | Paul Mackerras <paulus@samba.org> | 2007-05-08 03:37:51 (GMT) |
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committer | Paul Mackerras <paulus@samba.org> | 2007-05-08 03:37:51 (GMT) |
commit | 02bbc0f09c90cefdb2837605c96a66c5ce4ba2e1 (patch) | |
tree | 04ef573cd4de095c500c9fc3477f4278c0b36300 /include/asm-blackfin/semaphore-helper.h | |
parent | 7487a2245b8841c77ba9db406cf99a483b9334e9 (diff) | |
parent | 5b94f675f57e4ff16c8fda09088d7480a84dcd91 (diff) | |
download | linux-fsl-qoriq-02bbc0f09c90cefdb2837605c96a66c5ce4ba2e1.tar.xz |
Merge branch 'linux-2.6'
Diffstat (limited to 'include/asm-blackfin/semaphore-helper.h')
-rw-r--r-- | include/asm-blackfin/semaphore-helper.h | 82 |
1 files changed, 82 insertions, 0 deletions
diff --git a/include/asm-blackfin/semaphore-helper.h b/include/asm-blackfin/semaphore-helper.h new file mode 100644 index 0000000..9082b0d --- /dev/null +++ b/include/asm-blackfin/semaphore-helper.h @@ -0,0 +1,82 @@ +/* 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 <asm/errno.h> + +/* + * 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 */ |