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Blackfin: convert to asm-generic/mutex-dec.h for all systems 

The Blackfin mutex.h is merely a copy of an older asm-generic/mutex-dec.h,
so punt it and just use the common one directly.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
This commit is contained in:
Mike Frysinger 2011-05-29 12:17:22 -04:00
parent fb1d9be596
commit 50f92aa334
1 changed files with 1 additions and 76 deletions
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77
arch/blackfin/include/asm/mutex.h
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@ -1,76 +1 @@
/* #include <asm-generic/mutex-dec.h>
* Pull in the generic implementation for the mutex fastpath.
*
* TODO: implement optimized primitives instead, or leave the generic
* implementation in place, or pick the atomic_xchg() based generic
* implementation. (see asm-generic/mutex-xchg.h for details)
*
* Copyright 2006-2009 Analog Devices Inc.
*
* Licensed under the GPL-2 or later.
*/
#ifndef _ASM_MUTEX_H
#define _ASM_MUTEX_H
#ifndef CONFIG_SMP
#include <asm-generic/mutex.h>
#else
static inline void
__mutex_fastpath_lock(atomic_t *count, void (*fail_fn)(atomic_t *))
{
if (unlikely(atomic_dec_return(count) < 0))
fail_fn(count);
else
smp_mb();
}
static inline int
__mutex_fastpath_lock_retval(atomic_t *count, int (*fail_fn)(atomic_t *))
{
if (unlikely(atomic_dec_return(count) < 0))
return fail_fn(count);
else {
smp_mb();
return 0;
}
}
static inline void
__mutex_fastpath_unlock(atomic_t *count, void (*fail_fn)(atomic_t *))
{
smp_mb();
if (unlikely(atomic_inc_return(count) <= 0))
fail_fn(count);
}
#define __mutex_slowpath_needs_to_unlock() 1
static inline int
__mutex_fastpath_trylock(atomic_t *count, int (*fail_fn)(atomic_t *))
{
/*
* We have two variants here. The cmpxchg based one is the best one
* because it never induce a false contention state. It is included
* here because architectures using the inc/dec algorithms over the
* xchg ones are much more likely to support cmpxchg natively.
*
* If not we fall back to the spinlock based variant - that is
* just as efficient (and simpler) as a 'destructive' probing of
* the mutex state would be.
*/
#ifdef __HAVE_ARCH_CMPXCHG
if (likely(atomic_cmpxchg(count, 1, 0) == 1)) {
smp_mb();
return 1;
}
return 0;
#else
return fail_fn(count);
#endif
}
#endif
#endif