arch/mn10300/include/asm/barrier.h

   1 /* MN10300 memory barrier definitions
   2  *
   3  * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
   4  * Written by David Howells (dhowells@redhat.com)
   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 */