arch/ia64/include/asm/atomic.h

   1 #ifndef _ASM_IA64_ATOMIC_H
   2 #define _ASM_IA64_ATOMIC_H
   3
   4 /*
   5  * Atomic operations that C can't guarantee us.  Useful for
   6  * resource counting etc..
   7  *
   8  * NOTE: don't mess with the types below!  The "unsigned long" and
   9  * "int" types were carefully placed so as to ensure proper operation
  10  * of the macros.
  11  *
  12  * Copyright (C) 1998, 1999, 2002-2003 Hewlett-Packard Co
  13  *      David Mosberger-Tang <davidm@hpl.hp.com>
  14  */
  15 #include <linux/types.h>
  16
  17 #include <asm/intrinsics.h>
  18 #include <asm/barrier.h>
  19
  20
  21 #define ATOMIC_INIT(i)          { (i) }
  22 #define ATOMIC64_INIT(i)        { (i) }
  23
  24 #define atomic_read(v)          ACCESS_ONCE((v)->counter)
  25 #define atomic64_read(v)        ACCESS_ONCE((v)->counter)
  26
  27 #define atomic_set(v,i)         (((v)->counter) = (i))
  28 #define atomic64_set(v,i)       (((v)->counter) = (i))
  29
  30 #define ATOMIC_OP(op, c_op)                                             \
  31 static __inline__ int                                                   \
  32 ia64_atomic_##op (int i, atomic_t *v)                                   \
  33 {                                                                       \
  34         __s32 old, new;                                                 \
  35         CMPXCHG_BUGCHECK_DECL                                           \
  36                                                                         \
  37         do {                                                            \
  38                 CMPXCHG_BUGCHECK(v);                                    \
  39                 old = atomic_read(v);                                   \
  40                 new = old c_op i;                                       \
  41         } while (ia64_cmpxchg(acq, v, old, new, sizeof(atomic_t)) != old); \
  42         return new;                                                     \
  43 }
  44
  45 ATOMIC_OP(add, +)
  46 ATOMIC_OP(sub, -)
  47
  48 #undef ATOMIC_OP
  49
  50 #define atomic_add_return(i,v)                                          \
  51 ({                                                                      \
  52         int __ia64_aar_i = (i);                                         \
  53         (__builtin_constant_p(i)                                        \
  54          && (   (__ia64_aar_i ==  1) || (__ia64_aar_i ==   4)           \
  55              || (__ia64_aar_i ==  8) || (__ia64_aar_i ==  16)           \
  56              || (__ia64_aar_i == -1) || (__ia64_aar_i ==  -4)           \
  57              || (__ia64_aar_i == -8) || (__ia64_aar_i == -16)))         \
  58                 ? ia64_fetch_and_add(__ia64_aar_i, &(v)->counter)       \
  59                 : ia64_atomic_add(__ia64_aar_i, v);                     \
  60 })
  61
  62 #define atomic_sub_return(i,v)                                          \
  63 ({                                                                      \
  64         int __ia64_asr_i = (i);                                         \
  65         (__builtin_constant_p(i)                                        \
  66          && (   (__ia64_asr_i ==   1) || (__ia64_asr_i ==   4)          \
  67              || (__ia64_asr_i ==   8) || (__ia64_asr_i ==  16)          \
  68              || (__ia64_asr_i ==  -1) || (__ia64_asr_i ==  -4)          \
  69              || (__ia64_asr_i ==  -8) || (__ia64_asr_i == -16)))        \
  70                 ? ia64_fetch_and_add(-__ia64_asr_i, &(v)->counter)      \
  71                 : ia64_atomic_sub(__ia64_asr_i, v);                     \
  72 })
  73
  74 #define ATOMIC64_OP(op, c_op)                                           \
  75 static __inline__ long                                                  \
  76 ia64_atomic64_##op (__s64 i, atomic64_t *v)                             \
  77 {                                                                       \
  78         __s64 old, new;                                                 \
  79         CMPXCHG_BUGCHECK_DECL                                           \
  80                                                                         \
  81         do {                                                            \
  82                 CMPXCHG_BUGCHECK(v);                                    \
  83                 old = atomic64_read(v);                                 \
  84                 new = old c_op i;                                       \
  85         } while (ia64_cmpxchg(acq, v, old, new, sizeof(atomic64_t)) != old); \
  86         return new;                                                     \
  87 }
  88
  89 ATOMIC64_OP(add, +)
  90 ATOMIC64_OP(sub, -)
  91
  92 #undef ATOMIC64_OP
  93
  94 #define atomic64_add_return(i,v)                                        \
  95 ({                                                                      \
  96         long __ia64_aar_i = (i);                                        \
  97         (__builtin_constant_p(i)                                        \
  98          && (   (__ia64_aar_i ==  1) || (__ia64_aar_i ==   4)           \
  99              || (__ia64_aar_i ==  8) || (__ia64_aar_i ==  16)           \
 100              || (__ia64_aar_i == -1) || (__ia64_aar_i ==  -4)           \
 101              || (__ia64_aar_i == -8) || (__ia64_aar_i == -16)))         \
 102                 ? ia64_fetch_and_add(__ia64_aar_i, &(v)->counter)       \
 103                 : ia64_atomic64_add(__ia64_aar_i, v);                   \
 104 })
 105
 106 #define atomic64_sub_return(i,v)                                        \
 107 ({                                                                      \
 108         long __ia64_asr_i = (i);                                        \
 109         (__builtin_constant_p(i)                                        \
 110          && (   (__ia64_asr_i ==   1) || (__ia64_asr_i ==   4)          \
 111              || (__ia64_asr_i ==   8) || (__ia64_asr_i ==  16)          \
 112              || (__ia64_asr_i ==  -1) || (__ia64_asr_i ==  -4)          \
 113              || (__ia64_asr_i ==  -8) || (__ia64_asr_i == -16)))        \
 114                 ? ia64_fetch_and_add(-__ia64_asr_i, &(v)->counter)      \
 115                 : ia64_atomic64_sub(__ia64_asr_i, v);                   \
 116 })
 117
 118 #define atomic_cmpxchg(v, old, new) (cmpxchg(&((v)->counter), old, new))
 119 #define atomic_xchg(v, new) (xchg(&((v)->counter), new))
 120
 121 #define atomic64_cmpxchg(v, old, new) \
 122         (cmpxchg(&((v)->counter), old, new))
 123 #define atomic64_xchg(v, new) (xchg(&((v)->counter), new))
 124
 125 static __inline__ int __atomic_add_unless(atomic_t *v, int a, int u)
 126 {
 127         int c, old;
 128         c = atomic_read(v);
 129         for (;;) {
 130                 if (unlikely(c == (u)))
 131                         break;
 132                 old = atomic_cmpxchg((v), c, c + (a));
 133                 if (likely(old == c))
 134                         break;
 135                 c = old;
 136         }
 137         return c;
 138 }
 139
 140
 141 static __inline__ long atomic64_add_unless(atomic64_t *v, long a, long u)
 142 {
 143         long c, old;
 144         c = atomic64_read(v);
 145         for (;;) {
 146                 if (unlikely(c == (u)))
 147                         break;
 148                 old = atomic64_cmpxchg((v), c, c + (a));
 149                 if (likely(old == c))
 150                         break;
 151                 c = old;
 152         }
 153         return c != (u);
 154 }
 155
 156 #define atomic64_inc_not_zero(v) atomic64_add_unless((v), 1, 0)
 157
 158 /*
 159  * Atomically add I to V and return TRUE if the resulting value is
 160  * negative.
 161  */
 162 static __inline__ int
 163 atomic_add_negative (int i, atomic_t *v)
 164 {
 165         return atomic_add_return(i, v) < 0;
 166 }
 167
 168 static __inline__ long
 169 atomic64_add_negative (__s64 i, atomic64_t *v)
 170 {
 171         return atomic64_add_return(i, v) < 0;
 172 }
 173
 174 #define atomic_dec_return(v)            atomic_sub_return(1, (v))
 175 #define atomic_inc_return(v)            atomic_add_return(1, (v))
 176 #define atomic64_dec_return(v)          atomic64_sub_return(1, (v))
 177 #define atomic64_inc_return(v)          atomic64_add_return(1, (v))
 178
 179 #define atomic_sub_and_test(i,v)        (atomic_sub_return((i), (v)) == 0)
 180 #define atomic_dec_and_test(v)          (atomic_sub_return(1, (v)) == 0)
 181 #define atomic_inc_and_test(v)          (atomic_add_return(1, (v)) == 0)
 182 #define atomic64_sub_and_test(i,v)      (atomic64_sub_return((i), (v)) == 0)
 183 #define atomic64_dec_and_test(v)        (atomic64_sub_return(1, (v)) == 0)
 184 #define atomic64_inc_and_test(v)        (atomic64_add_return(1, (v)) == 0)
 185
 186 #define atomic_add(i,v)                 (void)atomic_add_return((i), (v))
 187 #define atomic_sub(i,v)                 (void)atomic_sub_return((i), (v))
 188 #define atomic_inc(v)                   atomic_add(1, (v))
 189 #define atomic_dec(v)                   atomic_sub(1, (v))
 190
 191 #define atomic64_add(i,v)               (void)atomic64_add_return((i), (v))
 192 #define atomic64_sub(i,v)               (void)atomic64_sub_return((i), (v))
 193 #define atomic64_inc(v)                 atomic64_add(1, (v))
 194 #define atomic64_dec(v)                 atomic64_sub(1, (v))
 195
 196 #endif /* _ASM_IA64_ATOMIC_H */