LXR linux/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 */
  38