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 <[email protected]>
  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)          READ_ONCE((v)->counter)
  25 #define atomic64_read(v)        READ_ONCE((v)->counter)
  26
  27 #define atomic_set(v,i)         WRITE_ONCE(((v)->counter), (i))
  28 #define atomic64_set(v,i)       WRITE_ONCE(((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 #define atomic_add_return(i,v)                                          \
  49 ({                                                                      \
  50         int __ia64_aar_i = (i);                                         \
  51         (__builtin_constant_p(i)                                        \
  52          && (   (__ia64_aar_i ==  1) || (__ia64_aar_i ==   4)           \
  53              || (__ia64_aar_i ==  8) || (__ia64_aar_i ==  16)           \
  54              || (__ia64_aar_i == -1) || (__ia64_aar_i ==  -4)           \
  55              || (__ia64_aar_i == -8) || (__ia64_aar_i == -16)))         \
  56                 ? ia64_fetch_and_add(__ia64_aar_i, &(v)->counter)       \
  57                 : ia64_atomic_add(__ia64_aar_i, v);                     \
  58 })
  59
  60 #define atomic_sub_return(i,v)                                          \
  61 ({                                                                      \
  62         int __ia64_asr_i = (i);                                         \
  63         (__builtin_constant_p(i)                                        \
  64          && (   (__ia64_asr_i ==   1) || (__ia64_asr_i ==   4)          \
  65              || (__ia64_asr_i ==   8) || (__ia64_asr_i ==  16)          \
  66              || (__ia64_asr_i ==  -1) || (__ia64_asr_i ==  -4)          \
  67              || (__ia64_asr_i ==  -8) || (__ia64_asr_i == -16)))        \
  68                 ? ia64_fetch_and_add(-__ia64_asr_i, &(v)->counter)      \
  69                 : ia64_atomic_sub(__ia64_asr_i, v);                     \
  70 })
  71
  72 ATOMIC_OP(and, &)
  73 ATOMIC_OP(or, |)
  74 ATOMIC_OP(xor, ^)
  75
  76 #define atomic_and(i,v) (void)ia64_atomic_and(i,v)
  77 #define atomic_or(i,v)  (void)ia64_atomic_or(i,v)
  78 #define atomic_xor(i,v) (void)ia64_atomic_xor(i,v)
  79
  80 #undef ATOMIC_OP
  81
  82 #define ATOMIC64_OP(op, c_op)                                           \
  83 static __inline__ long                                                  \
  84 ia64_atomic64_##op (__s64 i, atomic64_t *v)                             \
  85 {                                                                       \
  86         __s64 old, new;                                                 \
  87         CMPXCHG_BUGCHECK_DECL                                           \
  88                                                                         \
  89         do {                                                            \
  90                 CMPXCHG_BUGCHECK(v);                                    \
  91                 old = atomic64_read(v);                                 \
  92                 new = old c_op i;                                       \
  93         } while (ia64_cmpxchg(acq, v, old, new, sizeof(atomic64_t)) != old); \
  94         return new;                                                     \
  95 }
  96
  97 ATOMIC64_OP(add, +)
  98 ATOMIC64_OP(sub, -)
  99
 100 #define atomic64_add_return(i,v)                                        \
 101 ({                                                                      \
 102         long __ia64_aar_i = (i);                                        \
 103         (__builtin_constant_p(i)                                        \
 104          && (   (__ia64_aar_i ==  1) || (__ia64_aar_i ==   4)           \
 105              || (__ia64_aar_i ==  8) || (__ia64_aar_i ==  16)           \
 106              || (__ia64_aar_i == -1) || (__ia64_aar_i ==  -4)           \
 107              || (__ia64_aar_i == -8) || (__ia64_aar_i == -16)))         \
 108                 ? ia64_fetch_and_add(__ia64_aar_i, &(v)->counter)       \
 109                 : ia64_atomic64_add(__ia64_aar_i, v);                   \
 110 })
 111
 112 #define atomic64_sub_return(i,v)                                        \
 113 ({                                                                      \
 114         long __ia64_asr_i = (i);                                        \
 115         (__builtin_constant_p(i)                                        \
 116          && (   (__ia64_asr_i ==   1) || (__ia64_asr_i ==   4)          \
 117              || (__ia64_asr_i ==   8) || (__ia64_asr_i ==  16)          \
 118              || (__ia64_asr_i ==  -1) || (__ia64_asr_i ==  -4)          \
 119              || (__ia64_asr_i ==  -8) || (__ia64_asr_i == -16)))        \
 120                 ? ia64_fetch_and_add(-__ia64_asr_i, &(v)->counter)      \
 121                 : ia64_atomic64_sub(__ia64_asr_i, v);                   \
 122 })
 123
 124 ATOMIC64_OP(and, &)
 125 ATOMIC64_OP(or, |)
 126 ATOMIC64_OP(xor, ^)
 127
 128 #define atomic64_and(i,v)       (void)ia64_atomic64_and(i,v)
 129 #define atomic64_or(i,v)        (void)ia64_atomic64_or(i,v)
 130 #define atomic64_xor(i,v)       (void)ia64_atomic64_xor(i,v)
 131
 132 #undef ATOMIC64_OP
 133
 134 #define atomic_cmpxchg(v, old, new) (cmpxchg(&((v)->counter), old, new))
 135 #define atomic_xchg(v, new) (xchg(&((v)->counter), new))
 136
 137 #define atomic64_cmpxchg(v, old, new) \
 138         (cmpxchg(&((v)->counter), old, new))
 139 #define atomic64_xchg(v, new) (xchg(&((v)->counter), new))
 140
 141 static __inline__ int __atomic_add_unless(atomic_t *v, int a, int u)
 142 {
 143         int c, old;
 144         c = atomic_read(v);
 145         for (;;) {
 146                 if (unlikely(c == (u)))
 147                         break;
 148                 old = atomic_cmpxchg((v), c, c + (a));
 149                 if (likely(old == c))
 150                         break;
 151                 c = old;
 152         }
 153         return c;
 154 }
 155
 156
 157 static __inline__ long atomic64_add_unless(atomic64_t *v, long a, long u)
 158 {
 159         long c, old;
 160         c = atomic64_read(v);
 161         for (;;) {
 162                 if (unlikely(c == (u)))
 163                         break;
 164                 old = atomic64_cmpxchg((v), c, c + (a));
 165                 if (likely(old == c))
 166                         break;
 167                 c = old;
 168         }
 169         return c != (u);
 170 }
 171
 172 #define atomic64_inc_not_zero(v) atomic64_add_unless((v), 1, 0)
 173
 174 /*
 175  * Atomically add I to V and return TRUE if the resulting value is
 176  * negative.
 177  */
 178 static __inline__ int
 179 atomic_add_negative (int i, atomic_t *v)
 180 {
 181         return atomic_add_return(i, v) < 0;
 182 }
 183
 184 static __inline__ long
 185 atomic64_add_negative (__s64 i, atomic64_t *v)
 186 {
 187         return atomic64_add_return(i, v) < 0;
 188 }
 189
 190 #define atomic_dec_return(v)            atomic_sub_return(1, (v))
 191 #define atomic_inc_return(v)            atomic_add_return(1, (v))
 192 #define atomic64_dec_return(v)          atomic64_sub_return(1, (v))
 193 #define atomic64_inc_return(v)          atomic64_add_return(1, (v))
 194
 195 #define atomic_sub_and_test(i,v)        (atomic_sub_return((i), (v)) == 0)
 196 #define atomic_dec_and_test(v)          (atomic_sub_return(1, (v)) == 0)
 197 #define atomic_inc_and_test(v)          (atomic_add_return(1, (v)) == 0)
 198 #define atomic64_sub_and_test(i,v)      (atomic64_sub_return((i), (v)) == 0)
 199 #define atomic64_dec_and_test(v)        (atomic64_sub_return(1, (v)) == 0)
 200 #define atomic64_inc_and_test(v)        (atomic64_add_return(1, (v)) == 0)
 201
 202 #define atomic_add(i,v)                 (void)atomic_add_return((i), (v))
 203 #define atomic_sub(i,v)                 (void)atomic_sub_return((i), (v))
 204 #define atomic_inc(v)                   atomic_add(1, (v))
 205 #define atomic_dec(v)                   atomic_sub(1, (v))
 206
 207 #define atomic64_add(i,v)               (void)atomic64_add_return((i), (v))
 208 #define atomic64_sub(i,v)               (void)atomic64_sub_return((i), (v))
 209 #define atomic64_inc(v)                 atomic64_add(1, (v))
 210 #define atomic64_dec(v)                 atomic64_sub(1, (v))
 211
 212 #endif /* _ASM_IA64_ATOMIC_H */