LXR linux/include/asm-generic/atomic64.h

   1/*
   2 * Generic implementation of 64-bit atomics using spinlocks,
   3 * useful on processors that don't have 64-bit atomic instructions.
   4 *
   5 * Copyright © 2009 Paul Mackerras, IBM Corp. <paulus@au1.ibm.com>
   6 *
   7 * This program is free software; you can redistribute it and/or
   8 * modify it under the terms of the GNU General Public License
   9 * as published by the Free Software Foundation; either version
  10 * 2 of the License, or (at your option) any later version.
  11 */
  12#ifndef _ASM_GENERIC_ATOMIC64_H
  13#define _ASM_GENERIC_ATOMIC64_H
  14#include <linux/types.h>
  15
  16typedef struct {
  17        long long counter;
  18} atomic64_t;
  19
  20#define ATOMIC64_INIT(i)        { (i) }
  21
  22extern long long atomic64_read(const atomic64_t *v);
  23extern void      atomic64_set(atomic64_t *v, long long i);
  24
  25#define atomic64_set_release(v, i)      atomic64_set((v), (i))
  26
  27#define ATOMIC64_OP(op)                                                 \
  28extern void      atomic64_##op(long long a, atomic64_t *v);
  29
  30#define ATOMIC64_OP_RETURN(op)                                          \
  31extern long long atomic64_##op##_return(long long a, atomic64_t *v);
  32
  33#define ATOMIC64_FETCH_OP(op)                                           \
  34extern long long atomic64_fetch_##op(long long a, atomic64_t *v);
  35
  36#define ATOMIC64_OPS(op)        ATOMIC64_OP(op) ATOMIC64_OP_RETURN(op) ATOMIC64_FETCH_OP(op)
  37
  38ATOMIC64_OPS(add)
  39ATOMIC64_OPS(sub)
  40
  41#undef ATOMIC64_OPS
  42#define ATOMIC64_OPS(op)        ATOMIC64_OP(op) ATOMIC64_FETCH_OP(op)
  43
  44ATOMIC64_OPS(and)
  45ATOMIC64_OPS(or)
  46ATOMIC64_OPS(xor)
  47
  48#undef ATOMIC64_OPS
  49#undef ATOMIC64_FETCH_OP
  50#undef ATOMIC64_OP_RETURN
  51#undef ATOMIC64_OP
  52
  53extern long long atomic64_dec_if_positive(atomic64_t *v);
  54#define atomic64_dec_if_positive atomic64_dec_if_positive
  55extern long long atomic64_cmpxchg(atomic64_t *v, long long o, long long n);
  56extern long long atomic64_xchg(atomic64_t *v, long long new);
  57extern long long atomic64_fetch_add_unless(atomic64_t *v, long long a, long long u);
  58#define atomic64_fetch_add_unless atomic64_fetch_add_unless
  59
  60#endif  /*  _ASM_GENERIC_ATOMIC64_H  */
  61