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