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