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-rw-r--r--arch/x86/include/asm/mutex_32.h110
1 files changed, 0 insertions, 110 deletions
diff --git a/arch/x86/include/asm/mutex_32.h b/arch/x86/include/asm/mutex_32.h
deleted file mode 100644
index e9355a84fc67..000000000000
--- a/arch/x86/include/asm/mutex_32.h
+++ /dev/null
@@ -1,110 +0,0 @@
-/*
- * Assembly implementation of the mutex fastpath, based on atomic
- * decrement/increment.
- *
- * started by Ingo Molnar:
- *
- * Copyright (C) 2004, 2005, 2006 Red Hat, Inc., Ingo Molnar <mingo@redhat.com>
- */
-#ifndef _ASM_X86_MUTEX_32_H
-#define _ASM_X86_MUTEX_32_H
-
-#include <asm/alternative.h>
-
-/**
- * __mutex_fastpath_lock - try to take the lock by moving the count
- * from 1 to a 0 value
- * @count: pointer of type atomic_t
- * @fn: function to call if the original value was not 1
- *
- * Change the count from 1 to a value lower than 1, and call <fn> if it
- * wasn't 1 originally. This function MUST leave the value lower than 1
- * even when the "1" assertion wasn't true.
- */
-#define __mutex_fastpath_lock(count, fail_fn) \
-do { \
- unsigned int dummy; \
- \
- typecheck(atomic_t *, count); \
- typecheck_fn(void (*)(atomic_t *), fail_fn); \
- \
- asm volatile(LOCK_PREFIX " decl (%%eax)\n" \
- " jns 1f \n" \
- " call " #fail_fn "\n" \
- "1:\n" \
- : "=a" (dummy) \
- : "a" (count) \
- : "memory", "ecx", "edx"); \
-} while (0)
-
-
-/**
- * __mutex_fastpath_lock_retval - try to take the lock by moving the count
- * from 1 to a 0 value
- * @count: pointer of type atomic_t
- *
- * Change the count from 1 to a value lower than 1. This function returns 0
- * if the fastpath succeeds, or -1 otherwise.
- */
-static inline int __mutex_fastpath_lock_retval(atomic_t *count)
-{
- if (unlikely(atomic_dec_return(count) < 0))
- return -1;
- else
- return 0;
-}
-
-/**
- * __mutex_fastpath_unlock - try to promote the mutex from 0 to 1
- * @count: pointer of type atomic_t
- * @fail_fn: function to call if the original value was not 0
- *
- * try to promote the mutex from 0 to 1. if it wasn't 0, call <fail_fn>.
- * In the failure case, this function is allowed to either set the value
- * to 1, or to set it to a value lower than 1.
- *
- * If the implementation sets it to a value of lower than 1, the
- * __mutex_slowpath_needs_to_unlock() macro needs to return 1, it needs
- * to return 0 otherwise.
- */
-#define __mutex_fastpath_unlock(count, fail_fn) \
-do { \
- unsigned int dummy; \
- \
- typecheck(atomic_t *, count); \
- typecheck_fn(void (*)(atomic_t *), fail_fn); \
- \
- asm volatile(LOCK_PREFIX " incl (%%eax)\n" \
- " jg 1f\n" \
- " call " #fail_fn "\n" \
- "1:\n" \
- : "=a" (dummy) \
- : "a" (count) \
- : "memory", "ecx", "edx"); \
-} while (0)
-
-#define __mutex_slowpath_needs_to_unlock() 1
-
-/**
- * __mutex_fastpath_trylock - try to acquire the mutex, without waiting
- *
- * @count: pointer of type atomic_t
- * @fail_fn: fallback function
- *
- * Change the count from 1 to a value lower than 1, and return 0 (failure)
- * if it wasn't 1 originally, or return 1 (success) otherwise. This function
- * MUST leave the value lower than 1 even when the "1" assertion wasn't true.
- * Additionally, if the value was < 0 originally, this function must not leave
- * it to 0 on failure.
- */
-static inline int __mutex_fastpath_trylock(atomic_t *count,
- int (*fail_fn)(atomic_t *))
-{
- /* cmpxchg because it never induces a false contention state. */
- if (likely(atomic_read(count) == 1 && atomic_cmpxchg(count, 1, 0) == 1))
- return 1;
-
- return 0;
-}
-
-#endif /* _ASM_X86_MUTEX_32_H */