LXR linux/arch/xtensa/include/asm/barrier.h

   1/*
   2 * This file is subject to the terms and conditions of the GNU General Public
   3 * License.  See the file "COPYING" in the main directory of this archive
   4 * for more details.
   5 *
   6 * Copyright (C) 2001 - 2012 Tensilica Inc.
   7 */
   8
   9#ifndef _XTENSA_SYSTEM_H
  10#define _XTENSA_SYSTEM_H
  11
  12#define smp_read_barrier_depends() do { } while(0)
  13#define read_barrier_depends() do { } while(0)
  14
  15#define mb()  ({ __asm__ __volatile__("memw" : : : "memory"); })
  16#define rmb() barrier()
  17#define wmb() mb()
  18
  19#ifdef CONFIG_SMP
  20#error smp_* not defined
  21#else
  22#define smp_mb()        barrier()
  23#define smp_rmb()       barrier()
  24#define smp_wmb()       barrier()
  25#endif
  26
  27#define set_mb(var, value)      do { var = value; mb(); } while (0)
  28
  29#endif /* _XTENSA_SYSTEM_H */
  30