LXR linux/include/asm-sparc64/atomic.h

   1/* $Id: atomic.h,v 1.22 2001/07/11 23:56:07 davem Exp $
   2 * atomic.h: Thankfully the V9 is at least reasonable for this
   3 *           stuff.
   4 *
   5 * Copyright (C) 1996, 1997, 2000 David S. Miller (davem@redhat.com)
   6 */
   7
   8#ifndef __ARCH_SPARC64_ATOMIC__
   9#define __ARCH_SPARC64_ATOMIC__
  10
  11#include <linux/types.h>
  12
  13typedef struct { volatile int counter; } atomic_t;
  14typedef struct { volatile __s64 counter; } atomic64_t;
  15
  16#define ATOMIC_INIT(i)          { (i) }
  17#define ATOMIC64_INIT(i)        { (i) }
  18
  19#define atomic_read(v)          ((v)->counter)
  20#define atomic64_read(v)        ((v)->counter)
  21
  22#define atomic_set(v, i)        (((v)->counter) = i)
  23#define atomic64_set(v, i)      (((v)->counter) = i)
  24
  25extern void atomic_add(int, atomic_t *);
  26extern void atomic64_add(int, atomic64_t *);
  27extern void atomic_sub(int, atomic_t *);
  28extern void atomic64_sub(int, atomic64_t *);
  29
  30extern int atomic_add_ret(int, atomic_t *);
  31extern int atomic64_add_ret(int, atomic64_t *);
  32extern int atomic_sub_ret(int, atomic_t *);
  33extern int atomic64_sub_ret(int, atomic64_t *);
  34
  35#define atomic_dec_return(v) atomic_sub_ret(1, v)
  36#define atomic64_dec_return(v) atomic64_sub_ret(1, v)
  37
  38#define atomic_inc_return(v) atomic_add_ret(1, v)
  39#define atomic64_inc_return(v) atomic64_add_ret(1, v)
  40
  41#define atomic_sub_return(i, v) atomic_sub_ret(i, v)
  42#define atomic64_sub_return(i, v) atomic64_sub_ret(i, v)
  43
  44#define atomic_add_return(i, v) atomic_add_ret(i, v)
  45#define atomic64_add_return(i, v) atomic64_add_ret(i, v)
  46
  47/*
  48 * atomic_inc_and_test - increment and test
  49 * @v: pointer of type atomic_t
  50 *
  51 * Atomically increments @v by 1
  52 * and returns true if the result is zero, or false for all
  53 * other cases.
  54 */
  55#define atomic_inc_and_test(v) (atomic_inc_return(v) == 0)
  56#define atomic64_inc_and_test(v) (atomic64_inc_return(v) == 0)
  57
  58#define atomic_sub_and_test(i, v) (atomic_sub_ret(i, v) == 0)
  59#define atomic64_sub_and_test(i, v) (atomic64_sub_ret(i, v) == 0)
  60
  61#define atomic_dec_and_test(v) (atomic_sub_ret(1, v) == 0)
  62#define atomic64_dec_and_test(v) (atomic64_sub_ret(1, v) == 0)
  63
  64#define atomic_inc(v) atomic_add(1, v)
  65#define atomic64_inc(v) atomic64_add(1, v)
  66
  67#define atomic_dec(v) atomic_sub(1, v)
  68#define atomic64_dec(v) atomic64_sub(1, v)
  69
  70#define atomic_add_negative(i, v) (atomic_add_ret(i, v) < 0)
  71#define atomic64_add_negative(i, v) (atomic64_add_ret(i, v) < 0)
  72
  73#define atomic_cmpxchg(v, o, n) ((int)cmpxchg(&((v)->counter), (o), (n)))
  74#define atomic_xchg(v, new) (xchg(&((v)->counter), new))
  75
  76#define atomic_add_unless(v, a, u)                              \
  77({                                                              \
  78        int c, old;                                             \
  79        c = atomic_read(v);                                     \
  80        for (;;) {                                              \
  81                if (unlikely(c == (u)))                         \
  82                        break;                                  \
  83                old = atomic_cmpxchg((v), c, c + (a));          \
  84                if (likely(old == c))                           \
  85                        break;                                  \
  86                c = old;                                        \
  87        }                                                       \
  88        likely(c != (u));                                       \
  89})
  90#define atomic_inc_not_zero(v) atomic_add_unless((v), 1, 0)
  91
  92/* Atomic operations are already serializing */
  93#ifdef CONFIG_SMP
  94#define smp_mb__before_atomic_dec()     membar_storeload_loadload();
  95#define smp_mb__after_atomic_dec()      membar_storeload_storestore();
  96#define smp_mb__before_atomic_inc()     membar_storeload_loadload();
  97#define smp_mb__after_atomic_inc()      membar_storeload_storestore();
  98#else
  99#define smp_mb__before_atomic_dec()     barrier()
 100#define smp_mb__after_atomic_dec()      barrier()
 101#define smp_mb__before_atomic_inc()     barrier()
 102#define smp_mb__after_atomic_inc()      barrier()
 103#endif
 104
 105#include <asm-generic/atomic.h>
 106#endif /* !(__ARCH_SPARC64_ATOMIC__) */
 107