LXR linux/arch/sparc/include/asm/atomic

   1/* atomic.h: Thankfully the V9 is at least reasonable for this
   2 *           stuff.
   3 *
   4 * Copyright (C) 1996, 1997, 2000, 2012 David S. Miller (davem@redhat.com)
   5 */
   6
   7#ifndef __ARCH_SPARC64_ATOMIC__
   8#define __ARCH_SPARC64_ATOMIC__
   9
  10#include <linux/types.h>
  11#include <asm/cmpxchg.h>
  12#include <asm/barrier.h>
  13
  14#define ATOMIC_INIT(i)          { (i) }
  15#define ATOMIC64_INIT(i)        { (i) }
  16
  17#define atomic_read(v)          ACCESS_ONCE((v)->counter)
  18#define atomic64_read(v)        ACCESS_ONCE((v)->counter)
  19
  20#define atomic_set(v, i)        (((v)->counter) = i)
  21#define atomic64_set(v, i)      (((v)->counter) = i)
  22
  23#define ATOMIC_OP(op)                                                   \
  24void atomic_##op(int, atomic_t *);                                      \
  25void atomic64_##op(long, atomic64_t *);
  26
  27#define ATOMIC_OP_RETURN(op)                                            \
  28int atomic_##op##_return(int, atomic_t *);                              \
  29long atomic64_##op##_return(long, atomic64_t *);
  30
  31#define ATOMIC_OPS(op) ATOMIC_OP(op) ATOMIC_OP_RETURN(op)
  32
  33ATOMIC_OPS(add)
  34ATOMIC_OPS(sub)
  35
  36#undef ATOMIC_OPS
  37#undef ATOMIC_OP_RETURN
  38#undef ATOMIC_OP
  39
  40#define atomic_dec_return(v)   atomic_sub_return(1, v)
  41#define atomic64_dec_return(v) atomic64_sub_return(1, v)
  42
  43#define atomic_inc_return(v)   atomic_add_return(1, v)
  44#define atomic64_inc_return(v) atomic64_add_return(1, v)
  45
  46/*
  47 * atomic_inc_and_test - increment and test
  48 * @v: pointer of type atomic_t
  49 *
  50 * Atomically increments @v by 1
  51 * and returns true if the result is zero, or false for all
  52 * other cases.
  53 */
  54#define atomic_inc_and_test(v) (atomic_inc_return(v) == 0)
  55#define atomic64_inc_and_test(v) (atomic64_inc_return(v) == 0)
  56
  57#define atomic_sub_and_test(i, v) (atomic_sub_return(i, v) == 0)
  58#define atomic64_sub_and_test(i, v) (atomic64_sub_return(i, v) == 0)
  59
  60#define atomic_dec_and_test(v) (atomic_sub_return(1, v) == 0)
  61#define atomic64_dec_and_test(v) (atomic64_sub_return(1, v) == 0)
  62
  63#define atomic_inc(v) atomic_add(1, v)
  64#define atomic64_inc(v) atomic64_add(1, v)
  65
  66#define atomic_dec(v) atomic_sub(1, v)
  67#define atomic64_dec(v) atomic64_sub(1, v)
  68
  69#define atomic_add_negative(i, v) (atomic_add_return(i, v) < 0)
  70#define atomic64_add_negative(i, v) (atomic64_add_return(i, v) < 0)
  71
  72#define atomic_cmpxchg(v, o, n) (cmpxchg(&((v)->counter), (o), (n)))
  73#define atomic_xchg(v, new) (xchg(&((v)->counter), new))
  74
  75static inline int __atomic_add_unless(atomic_t *v, int a, int u)
  76{
  77        int c, old;
  78        c = atomic_read(v);
  79        for (;;) {
  80                if (unlikely(c == (u)))
  81                        break;
  82                old = atomic_cmpxchg((v), c, c + (a));
  83                if (likely(old == c))
  84                        break;
  85                c = old;
  86        }
  87        return c;
  88}
  89
  90#define atomic64_cmpxchg(v, o, n) \
  91        ((__typeof__((v)->counter))cmpxchg(&((v)->counter), (o), (n)))
  92#define atomic64_xchg(v, new) (xchg(&((v)->counter), new))
  93
  94static inline long atomic64_add_unless(atomic64_t *v, long a, long u)
  95{
  96        long c, old;
  97        c = atomic64_read(v);
  98        for (;;) {
  99                if (unlikely(c == (u)))
 100                        break;
 101                old = atomic64_cmpxchg((v), c, c + (a));
 102                if (likely(old == c))
 103                        break;
 104                c = old;
 105        }
 106        return c != (u);
 107}
 108
 109#define atomic64_inc_not_zero(v) atomic64_add_unless((v), 1, 0)
 110
 111long atomic64_dec_if_positive(atomic64_t *v);
 112
 113#endif /* !(__ARCH_SPARC64_ATOMIC__) */
 114