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-rw-r--r--include/asm-x86_64/mutex.h113
1 files changed, 0 insertions, 113 deletions
diff --git a/include/asm-x86_64/mutex.h b/include/asm-x86_64/mutex.h
deleted file mode 100644
index 11fbee2bd6c..00000000000
--- a/include/asm-x86_64/mutex.h
+++ /dev/null
@@ -1,113 +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_MUTEX_H
-#define _ASM_MUTEX_H
-
-/**
- * __mutex_fastpath_lock - decrement and call function if negative
- * @v: pointer of type atomic_t
- * @fail_fn: function to call if the result is negative
- *
- * Atomically decrements @v and calls <fail_fn> if the result is negative.
- */
-#define __mutex_fastpath_lock(v, fail_fn) \
-do { \
- unsigned long dummy; \
- \
- typecheck(atomic_t *, v); \
- typecheck_fn(fastcall void (*)(atomic_t *), fail_fn); \
- \
- __asm__ __volatile__( \
- LOCK " decl (%%rdi) \n" \
- " js 2f \n" \
- "1: \n" \
- \
- LOCK_SECTION_START("") \
- "2: call "#fail_fn" \n" \
- " jmp 1b \n" \
- LOCK_SECTION_END \
- \
- :"=D" (dummy) \
- : "D" (v) \
- : "rax", "rsi", "rdx", "rcx", \
- "r8", "r9", "r10", "r11", "memory"); \
-} 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
- * @fail_fn: function to call if the original value was not 1
- *
- * Change the count from 1 to a value lower than 1, and call <fail_fn> if
- * it wasn't 1 originally. This function returns 0 if the fastpath succeeds,
- * or anything the slow path function returns
- */
-static inline int
-__mutex_fastpath_lock_retval(atomic_t *count,
- int fastcall (*fail_fn)(atomic_t *))
-{
- if (unlikely(atomic_dec_return(count) < 0))
- return fail_fn(count);
- else
- return 0;
-}
-
-/**
- * __mutex_fastpath_unlock - increment and call function if nonpositive
- * @v: pointer of type atomic_t
- * @fail_fn: function to call if the result is nonpositive
- *
- * Atomically increments @v and calls <fail_fn> if the result is nonpositive.
- */
-#define __mutex_fastpath_unlock(v, fail_fn) \
-do { \
- unsigned long dummy; \
- \
- typecheck(atomic_t *, v); \
- typecheck_fn(fastcall void (*)(atomic_t *), fail_fn); \
- \
- __asm__ __volatile__( \
- LOCK " incl (%%rdi) \n" \
- " jle 2f \n" \
- "1: \n" \
- \
- LOCK_SECTION_START("") \
- "2: call "#fail_fn" \n" \
- " jmp 1b \n" \
- LOCK_SECTION_END \
- \
- :"=D" (dummy) \
- : "D" (v) \
- : "rax", "rsi", "rdx", "rcx", \
- "r8", "r9", "r10", "r11", "memory"); \
-} 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 0 and return 1 (success), or return 0 (failure)
- * if it wasn't 1 originally. [the fallback function is never used on
- * x86_64, because all x86_64 CPUs have a CMPXCHG instruction.]
- */
-static inline int
-__mutex_fastpath_trylock(atomic_t *count, int (*fail_fn)(atomic_t *))
-{
- if (likely(atomic_cmpxchg(count, 1, 0) == 1))
- return 1;
- else
- return 0;
-}
-
-#endif