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
  36ATOMIC_OP(and)
  37ATOMIC_OP(or)
  38ATOMIC_OP(xor)
  39
  40#undef ATOMIC_OPS
  41#undef ATOMIC_OP_RETURN
  42#undef ATOMIC_OP
  43
  44#define atomic_dec_return(v)   atomic_sub_return(1, v)
  45#define atomic64_dec_return(v) atomic64_sub_return(1, v)
  46
  47#define atomic_inc_return(v)   atomic_add_return(1, v)
  48#define atomic64_inc_return(v) atomic64_add_return(1, v)
  49
  50/*
  51 * atomic_inc_and_test - increment and test
  52 * @v: pointer of type atomic_t
  53 *
  54 * Atomically increments @v by 1
  55 * and returns true if the result is zero, or false for all
  56 * other cases.
  57 */
  58#define atomic_inc_and_test(v) (atomic_inc_return(v) == 0)
  59#define atomic64_inc_and_test(v) (atomic64_inc_return(v) == 0)
  60
  61#define atomic_sub_and_test(i, v) (atomic_sub_return(i, v) == 0)
  62#define atomic64_sub_and_test(i, v) (atomic64_sub_return(i, v) == 0)
  63
  64#define atomic_dec_and_test(v) (atomic_sub_return(1, v) == 0)
  65#define atomic64_dec_and_test(v) (atomic64_sub_return(1, v) == 0)
  66
  67#define atomic_inc(v) atomic_add(1, v)
  68#define atomic64_inc(v) atomic64_add(1, v)
  69
  70#define atomic_dec(v) atomic_sub(1, v)
  71#define atomic64_dec(v) atomic64_sub(1, v)
  72
  73#define atomic_add_negative(i, v) (atomic_add_return(i, v) < 0)
  74#define atomic64_add_negative(i, v) (atomic64_add_return(i, v) < 0)
  75
  76#define atomic_cmpxchg(v, o, n) (cmpxchg(&((v)->counter), (o), (n)))
  77#define atomic_xchg(v, new) (xchg(&((v)->counter), new))
  78
  79static inline int __atomic_add_unless(atomic_t *v, int a, int u)
  80{
  81        int c, old;
  82        c = atomic_read(v);
  83        for (;;) {
  84                if (unlikely(c == (u)))
  85                        break;
  86                old = atomic_cmpxchg((v), c, c + (a));
  87                if (likely(old == c))
  88                        break;
  89                c = old;
  90        }
  91        return c;
  92}
  93
  94#define atomic64_cmpxchg(v, o, n) \
  95        ((__typeof__((v)->counter))cmpxchg(&((v)->counter), (o), (n)))
  96#define atomic64_xchg(v, new) (xchg(&((v)->counter), new))
  97
  98static inline long atomic64_add_unless(atomic64_t *v, long a, long u)
  99{
 100        long c, old;
 101        c = atomic64_read(v);
 102        for (;;) {
 103                if (unlikely(c == (u)))
 104                        break;
 105                old = atomic64_cmpxchg((v), c, c + (a));
 106                if (likely(old == c))
 107                        break;
 108                c = old;
 109        }
 110        return c != (u);
 111}
 112
 113#define atomic64_inc_not_zero(v) atomic64_add_unless((v), 1, 0)
 114
 115long atomic64_dec_if_positive(atomic64_t *v);
 116
 117#endif /* !(__ARCH_SPARC64_ATOMIC__) */
 118