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@@ -1,112 +0,0 @@
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-/*
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- * include/asm-generic/mutex-dec.h
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- *
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- * Generic implementation of the mutex fastpath, based on atomic
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- * decrement/increment.
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- */
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-#ifndef _ASM_GENERIC_MUTEX_DEC_H
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-#define _ASM_GENERIC_MUTEX_DEC_H
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-
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-/**
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- * __mutex_fastpath_lock - try to take the lock by moving the count
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- * from 1 to a 0 value
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- * @count: pointer of type atomic_t
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- * @fail_fn: function to call if the original value was not 1
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- *
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- * Change the count from 1 to a value lower than 1, and call <fail_fn> if
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- * it wasn't 1 originally. This function MUST leave the value lower than
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- * 1 even when the "1" assertion wasn't true.
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- */
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-static inline void
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-__mutex_fastpath_lock(atomic_t *count, fastcall 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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-/**
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- * __mutex_fastpath_lock_retval - try to take the lock by moving the count
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- * from 1 to a 0 value
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- * @count: pointer of type atomic_t
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- * @fail_fn: function to call if the original value was not 1
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- *
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- * Change the count from 1 to a value lower than 1, and call <fail_fn> if
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- * it wasn't 1 originally. This function returns 0 if the fastpath succeeds,
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- * or anything the slow path function returns.
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- */
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-static inline int
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-__mutex_fastpath_lock_retval(atomic_t *count, fastcall 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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-/**
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- * __mutex_fastpath_unlock - try to promote the count from 0 to 1
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- * @count: pointer of type atomic_t
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- * @fail_fn: function to call if the original value was not 0
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- *
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- * Try to promote the count from 0 to 1. If it wasn't 0, call <fail_fn>.
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- * In the failure case, this function is allowed to either set the value to
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- * 1, or to set it to a value lower than 1.
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- *
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- * If the implementation sets it to a value of lower than 1, then the
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- * __mutex_slowpath_needs_to_unlock() macro needs to return 1, it needs
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- * to return 0 otherwise.
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- */
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-static inline void
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-__mutex_fastpath_unlock(atomic_t *count, fastcall 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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-/**
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- * __mutex_fastpath_trylock - try to acquire the mutex, without waiting
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- *
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- * @count: pointer of type atomic_t
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- * @fail_fn: fallback function
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- *
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- * Change the count from 1 to a value lower than 1, and return 0 (failure)
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- * if it wasn't 1 originally, or return 1 (success) otherwise. This function
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- * MUST leave the value lower than 1 even when the "1" assertion wasn't true.
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- * Additionally, if the value was < 0 originally, this function must not leave
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- * it to 0 on failure.
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- *
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- * If the architecture has no effective trylock variant, it should call the
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- * <fail_fn> spinlock-based trylock variant unconditionally.
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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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