LXR linux/arch/s390/include/asm/barrier.h

   1/*
   2 * Copyright IBM Corp. 1999, 2009
   3 *
   4 * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>
   5 */
   6
   7#ifndef __ASM_BARRIER_H
   8#define __ASM_BARRIER_H
   9
  10/*
  11 * Force strict CPU ordering.
  12 * And yes, this is required on UP too when we're talking
  13 * to devices.
  14 */
  15
  16#ifdef CONFIG_HAVE_MARCH_Z196_FEATURES
  17/* Fast-BCR without checkpoint synchronization */
  18#define __ASM_BARRIER "bcr 14,0\n"
  19#else
  20#define __ASM_BARRIER "bcr 15,0\n"
  21#endif
  22
  23#define mb() do {  asm volatile(__ASM_BARRIER : : : "memory"); } while (0)
  24
  25#define rmb()                           barrier()
  26#define wmb()                           barrier()
  27#define dma_rmb()                       mb()
  28#define dma_wmb()                       mb()
  29#define __smp_mb()                      mb()
  30#define __smp_rmb()                     rmb()
  31#define __smp_wmb()                     wmb()
  32
  33#define __smp_store_release(p, v)                                       \
  34do {                                                                    \
  35        compiletime_assert_atomic_type(*p);                             \
  36        barrier();                                                      \
  37        WRITE_ONCE(*p, v);                                              \
  38} while (0)
  39
  40#define __smp_load_acquire(p)                                           \
  41({                                                                      \
  42        typeof(*p) ___p1 = READ_ONCE(*p);                               \
  43        compiletime_assert_atomic_type(*p);                             \
  44        barrier();                                                      \
  45        ___p1;                                                          \
  46})
  47
  48#define __smp_mb__before_atomic()       barrier()
  49#define __smp_mb__after_atomic()        barrier()
  50
  51#include <asm-generic/barrier.h>
  52
  53#endif /* __ASM_BARRIER_H */
  54