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/system.h>
  19
  20
  21 #define ATOMIC_INIT(i)          ((atomic_t) { (i) })
  22 #define ATOMIC64_INIT(i)        ((atomic64_t) { (i) })
  23
  24 #define atomic_read(v)          (*(volatile int *)&(v)->counter)
  25 #define atomic64_read(v)        (*(volatile long *)&(v)->counter)
  26
  27 #define atomic_set(v,i)         (((v)->counter) = (i))
  28 #define atomic64_set(v,i)       (((v)->counter) = (i))
  29
  30 static __inline__ int
  31 ia64_atomic_add (int i, atomic_t *v)
  32 {
  33         __s32 old, new;
  34         CMPXCHG_BUGCHECK_DECL
  35
  36         do {
  37                 CMPXCHG_BUGCHECK(v);
  38                 old = atomic_read(v);
  39                 new = old + i;
  40         } while (ia64_cmpxchg(acq, v, old, new, sizeof(atomic_t)) != old);
  41         return new;
  42 }
  43
  44 static __inline__ int
  45 ia64_atomic64_add (__s64 i, atomic64_t *v)
  46 {
  47         __s64 old, new;
  48         CMPXCHG_BUGCHECK_DECL
  49
  50         do {
  51                 CMPXCHG_BUGCHECK(v);
  52                 old = atomic64_read(v);
  53                 new = old + i;
  54         } while (ia64_cmpxchg(acq, v, old, new, sizeof(atomic64_t)) != old);
  55         return new;
  56 }
  57
  58 static __inline__ int
  59 ia64_atomic_sub (int i, atomic_t *v)
  60 {
  61         __s32 old, new;
  62         CMPXCHG_BUGCHECK_DECL
  63
  64         do {
  65                 CMPXCHG_BUGCHECK(v);
  66                 old = atomic_read(v);
  67                 new = old - i;
  68         } while (ia64_cmpxchg(acq, v, old, new, sizeof(atomic_t)) != old);
  69         return new;
  70 }
  71
  72 static __inline__ int
  73 ia64_atomic64_sub (__s64 i, atomic64_t *v)
  74 {
  75         __s64 old, new;
  76         CMPXCHG_BUGCHECK_DECL
  77
  78         do {
  79                 CMPXCHG_BUGCHECK(v);
  80                 old = atomic64_read(v);
  81                 new = old - i;
  82         } while (ia64_cmpxchg(acq, v, old, new, sizeof(atomic64_t)) != old);
  83         return new;
  84 }
  85
  86 #define atomic_cmpxchg(v, old, new) (cmpxchg(&((v)->counter), old, new))
  87 #define atomic_xchg(v, new) (xchg(&((v)->counter), new))
  88
  89 #define atomic64_cmpxchg(v, old, new) \
  90         (cmpxchg(&((v)->counter), old, new))
  91 #define atomic64_xchg(v, new) (xchg(&((v)->counter), new))
  92
  93 static __inline__ int atomic_add_unless(atomic_t *v, int a, int u)
  94 {
  95         int c, old;
  96         c = atomic_read(v);
  97         for (;;) {
  98                 if (unlikely(c == (u)))
  99                         break;
 100                 old = atomic_cmpxchg((v), c, c + (a));
 101                 if (likely(old == c))
 102                         break;
 103                 c = old;
 104         }
 105         return c != (u);
 106 }
 107
 108 #define atomic_inc_not_zero(v) atomic_add_unless((v), 1, 0)
 109
 110 static __inline__ int atomic64_add_unless(atomic64_t *v, long a, long u)
 111 {
 112         long c, old;
 113         c = atomic64_read(v);
 114         for (;;) {
 115                 if (unlikely(c == (u)))
 116                         break;
 117                 old = atomic64_cmpxchg((v), c, c + (a));
 118                 if (likely(old == c))
 119                         break;
 120                 c = old;
 121         }
 122         return c != (u);
 123 }
 124
 125 #define atomic64_inc_not_zero(v) atomic64_add_unless((v), 1, 0)
 126
 127 #define atomic_add_return(i,v)                                          \
 128 ({                                                                      \
 129         int __ia64_aar_i = (i);                                         \
 130         (__builtin_constant_p(i)                                        \
 131          && (   (__ia64_aar_i ==  1) || (__ia64_aar_i ==   4)           \
 132              || (__ia64_aar_i ==  8) || (__ia64_aar_i ==  16)           \
 133              || (__ia64_aar_i == -1) || (__ia64_aar_i ==  -4)           \
 134              || (__ia64_aar_i == -8) || (__ia64_aar_i == -16)))         \
 135                 ? ia64_fetch_and_add(__ia64_aar_i, &(v)->counter)       \
 136                 : ia64_atomic_add(__ia64_aar_i, v);                     \
 137 })
 138
 139 #define atomic64_add_return(i,v)                                        \
 140 ({                                                                      \
 141         long __ia64_aar_i = (i);                                        \
 142         (__builtin_constant_p(i)                                        \
 143          && (   (__ia64_aar_i ==  1) || (__ia64_aar_i ==   4)           \
 144              || (__ia64_aar_i ==  8) || (__ia64_aar_i ==  16)           \
 145              || (__ia64_aar_i == -1) || (__ia64_aar_i ==  -4)           \
 146              || (__ia64_aar_i == -8) || (__ia64_aar_i == -16)))         \
 147                 ? ia64_fetch_and_add(__ia64_aar_i, &(v)->counter)       \
 148                 : ia64_atomic64_add(__ia64_aar_i, v);                   \
 149 })
 150
 151 /*
 152  * Atomically add I to V and return TRUE if the resulting value is
 153  * negative.
 154  */
 155 static __inline__ int
 156 atomic_add_negative (int i, atomic_t *v)
 157 {
 158         return atomic_add_return(i, v) < 0;
 159 }
 160
 161 static __inline__ int
 162 atomic64_add_negative (__s64 i, atomic64_t *v)
 163 {
 164         return atomic64_add_return(i, v) < 0;
 165 }
 166
 167 #define atomic_sub_return(i,v)                                          \
 168 ({                                                                      \
 169         int __ia64_asr_i = (i);                                         \
 170         (__builtin_constant_p(i)                                        \
 171          && (   (__ia64_asr_i ==   1) || (__ia64_asr_i ==   4)          \
 172              || (__ia64_asr_i ==   8) || (__ia64_asr_i ==  16)          \
 173              || (__ia64_asr_i ==  -1) || (__ia64_asr_i ==  -4)          \
 174              || (__ia64_asr_i ==  -8) || (__ia64_asr_i == -16)))        \
 175                 ? ia64_fetch_and_add(-__ia64_asr_i, &(v)->counter)      \
 176                 : ia64_atomic_sub(__ia64_asr_i, v);                     \
 177 })
 178
 179 #define atomic64_sub_return(i,v)                                        \
 180 ({                                                                      \
 181         long __ia64_asr_i = (i);                                        \
 182         (__builtin_constant_p(i)                                        \
 183          && (   (__ia64_asr_i ==   1) || (__ia64_asr_i ==   4)          \
 184              || (__ia64_asr_i ==   8) || (__ia64_asr_i ==  16)          \
 185              || (__ia64_asr_i ==  -1) || (__ia64_asr_i ==  -4)          \
 186              || (__ia64_asr_i ==  -8) || (__ia64_asr_i == -16)))        \
 187                 ? ia64_fetch_and_add(-__ia64_asr_i, &(v)->counter)      \
 188                 : ia64_atomic64_sub(__ia64_asr_i, v);                   \
 189 })
 190
 191 #define atomic_dec_return(v)            atomic_sub_return(1, (v))
 192 #define atomic_inc_return(v)            atomic_add_return(1, (v))
 193 #define atomic64_dec_return(v)          atomic64_sub_return(1, (v))
 194 #define atomic64_inc_return(v)          atomic64_add_return(1, (v))
 195
 196 #define atomic_sub_and_test(i,v)        (atomic_sub_return((i), (v)) == 0)
 197 #define atomic_dec_and_test(v)          (atomic_sub_return(1, (v)) == 0)
 198 #define atomic_inc_and_test(v)          (atomic_add_return(1, (v)) == 0)
 199 #define atomic64_sub_and_test(i,v)      (atomic64_sub_return((i), (v)) == 0)
 200 #define atomic64_dec_and_test(v)        (atomic64_sub_return(1, (v)) == 0)
 201 #define atomic64_inc_and_test(v)        (atomic64_add_return(1, (v)) == 0)
 202
 203 #define atomic_add(i,v)                 atomic_add_return((i), (v))
 204 #define atomic_sub(i,v)                 atomic_sub_return((i), (v))
 205 #define atomic_inc(v)                   atomic_add(1, (v))
 206 #define atomic_dec(v)                   atomic_sub(1, (v))
 207
 208 #define atomic64_add(i,v)               atomic64_add_return((i), (v))
 209 #define atomic64_sub(i,v)               atomic64_sub_return((i), (v))
 210 #define atomic64_inc(v)                 atomic64_add(1, (v))
 211 #define atomic64_dec(v)                 atomic64_sub(1, (v))
 212
 213 /* Atomic operations are already serializing */
 214 #define smp_mb__before_atomic_dec()     barrier()
 215 #define smp_mb__after_atomic_dec()      barrier()
 216 #define smp_mb__before_atomic_inc()     barrier()
 217 #define smp_mb__after_atomic_inc()      barrier()
 218
 219 #include <asm-generic/atomic-long.h>
 220 #endif /* _ASM_IA64_ATOMIC_H */