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barrier.h
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1 /* MN10300 memory barrier definitions
2  *
3  * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
4  * Written by David Howells ([email protected])
5  *
6  * This program is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU General Public Licence
8  * as published by the Free Software Foundation; either version
9  * 2 of the Licence, or (at your option) any later version.
10  */
11 #ifndef _ASM_BARRIER_H
12 #define _ASM_BARRIER_H
13 
14 #define nop() asm volatile ("nop")
15 
16 #define mb() asm volatile ("": : :"memory")
17 #define rmb() mb()
18 #define wmb() asm volatile ("": : :"memory")
19 
20 #ifdef CONFIG_SMP
21 #define smp_mb() mb()
22 #define smp_rmb() rmb()
23 #define smp_wmb() wmb()
24 #define set_mb(var, value) do { xchg(&var, value); } while (0)
25 #else /* CONFIG_SMP */
26 #define smp_mb() barrier()
27 #define smp_rmb() barrier()
28 #define smp_wmb() barrier()
29 #define set_mb(var, value) do { var = value; mb(); } while (0)
30 #endif /* CONFIG_SMP */
31 
32 #define set_wmb(var, value) do { var = value; wmb(); } while (0)
33 
34 #define read_barrier_depends() do {} while (0)
35 #define smp_read_barrier_depends() do {} while (0)
36 
37 #endif /* _ASM_BARRIER_H */