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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-cris/semaphore-helper.h | |
download | kernel_samsung_tuna-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.zip kernel_samsung_tuna-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.gz kernel_samsung_tuna-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.bz2 |
Linux-2.6.12-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-cris/semaphore-helper.h')
-rw-r--r-- | include/asm-cris/semaphore-helper.h | 81 |
1 files changed, 81 insertions, 0 deletions
diff --git a/include/asm-cris/semaphore-helper.h b/include/asm-cris/semaphore-helper.h new file mode 100644 index 0000000..dbd0f30 --- /dev/null +++ b/include/asm-cris/semaphore-helper.h @@ -0,0 +1,81 @@ +/* $Id: semaphore-helper.h,v 1.3 2001/03/26 15:00:33 orjanf Exp $ + * + * SMP- and interrupt-safe semaphores helper functions. Generic versions, no + * optimizations whatsoever... + * + */ + +#ifndef _ASM_SEMAPHORE_HELPER_H +#define _ASM_SEMAPHORE_HELPER_H + +#include <asm/atomic.h> +#include <linux/errno.h> + +#define read(a) ((a)->counter) +#define inc(a) (((a)->counter)++) +#define dec(a) (((a)->counter)--) + +#define count_inc(a) ((*(a))++) + +/* + * These two _must_ execute atomically wrt each other. + */ +extern inline void wake_one_more(struct semaphore * sem) +{ + atomic_inc(&sem->waking); +} + +extern inline int waking_non_zero(struct semaphore *sem) +{ + unsigned long flags; + int ret = 0; + + local_save_flags(flags); + local_irq_disable(); + if (read(&sem->waking) > 0) { + dec(&sem->waking); + ret = 1; + } + local_irq_restore(flags); + return ret; +} + +extern inline int waking_non_zero_interruptible(struct semaphore *sem, + struct task_struct *tsk) +{ + int ret = 0; + unsigned long flags; + + local_save_flags(flags); + local_irq_disable(); + if (read(&sem->waking) > 0) { + dec(&sem->waking); + ret = 1; + } else if (signal_pending(tsk)) { + inc(&sem->count); + ret = -EINTR; + } + local_irq_restore(flags); + return ret; +} + +extern inline int waking_non_zero_trylock(struct semaphore *sem) +{ + int ret = 1; + unsigned long flags; + + local_save_flags(flags); + local_irq_disable(); + if (read(&sem->waking) <= 0) + inc(&sem->count); + else { + dec(&sem->waking); + ret = 0; + } + local_irq_restore(flags); + return ret; +} + +#endif /* _ASM_SEMAPHORE_HELPER_H */ + + |