arch/alpha/include/asm/atomic.h

   1 #ifndef _ALPHA_ATOMIC_H
   2 #define _ALPHA_ATOMIC_H
   3
   4 #include <linux/types.h>
   5 #include <asm/barrier.h>
   6 #include <asm/cmpxchg.h>
   7
   8 /*
   9  * Atomic operations that C can't guarantee us.  Useful for
  10  * resource counting etc...
  11  *
  12  * But use these as seldom as possible since they are much slower
  13  * than regular operations.
  14  */
  15
  16
  17 #define ATOMIC_INIT(i)          { (i) }
  18 #define ATOMIC64_INIT(i)        { (i) }
  19
  20 #define atomic_read(v)          READ_ONCE((v)->counter)
  21 #define atomic64_read(v)        READ_ONCE((v)->counter)
  22
  23 #define atomic_set(v,i)         WRITE_ONCE((v)->counter, (i))
  24 #define atomic64_set(v,i)       WRITE_ONCE((v)->counter, (i))
  25
  26 /*
  27  * To get proper branch prediction for the main line, we must branch
  28  * forward to code at the end of this object's .text section, then
  29  * branch back to restart the operation.
  30  */
  31
  32 #define ATOMIC_OP(op, asm_op)                                           \
  33 static __inline__ void atomic_##op(int i, atomic_t * v)                 \
  34 {                                                                       \
  35         unsigned long temp;                                             \
  36         __asm__ __volatile__(                                           \
  37         "1:     ldl_l %0,%1\n"                                          \
  38         "       " #asm_op " %0,%2,%0\n"                                 \
  39         "       stl_c %0,%1\n"                                          \
  40         "       beq %0,2f\n"                                            \
  41         ".subsection 2\n"                                               \
  42         "2:     br 1b\n"                                                \
  43         ".previous"                                                     \
  44         :"=&r" (temp), "=m" (v->counter)                                \
  45         :"Ir" (i), "m" (v->counter));                                   \
  46 }                                                                       \
  47
  48 #define ATOMIC_OP_RETURN(op, asm_op)                                    \
  49 static inline int atomic_##op##_return_relaxed(int i, atomic_t *v)      \
  50 {                                                                       \
  51         long temp, result;                                              \
  52         __asm__ __volatile__(                                           \
  53         "1:     ldl_l %0,%1\n"                                          \
  54         "       " #asm_op " %0,%3,%2\n"                                 \
  55         "       " #asm_op " %0,%3,%0\n"                                 \
  56         "       stl_c %0,%1\n"                                          \
  57         "       beq %0,2f\n"                                            \
  58         ".subsection 2\n"                                               \
  59         "2:     br 1b\n"                                                \
  60         ".previous"                                                     \
  61         :"=&r" (temp), "=m" (v->counter), "=&r" (result)                \
  62         :"Ir" (i), "m" (v->counter) : "memory");                        \
  63         return result;                                                  \
  64 }
  65
  66 #define ATOMIC_FETCH_OP(op, asm_op)                                     \
  67 static inline int atomic_fetch_##op##_relaxed(int i, atomic_t *v)       \
  68 {                                                                       \
  69         long temp, result;                                              \
  70         __asm__ __volatile__(                                           \
  71         "1:     ldl_l %2,%1\n"                                          \
  72         "       " #asm_op " %2,%3,%0\n"                                 \
  73         "       stl_c %0,%1\n"                                          \
  74         "       beq %0,2f\n"                                            \
  75         ".subsection 2\n"                                               \
  76         "2:     br 1b\n"                                                \
  77         ".previous"                                                     \
  78         :"=&r" (temp), "=m" (v->counter), "=&r" (result)                \
  79         :"Ir" (i), "m" (v->counter) : "memory");                        \
  80         return result;                                                  \
  81 }
  82
  83 #define ATOMIC64_OP(op, asm_op)                                         \
  84 static __inline__ void atomic64_##op(long i, atomic64_t * v)            \
  85 {                                                                       \
  86         unsigned long temp;                                             \
  87         __asm__ __volatile__(                                           \
  88         "1:     ldq_l %0,%1\n"                                          \
  89         "       " #asm_op " %0,%2,%0\n"                                 \
  90         "       stq_c %0,%1\n"                                          \
  91         "       beq %0,2f\n"                                            \
  92         ".subsection 2\n"                                               \
  93         "2:     br 1b\n"                                                \
  94         ".previous"                                                     \
  95         :"=&r" (temp), "=m" (v->counter)                                \
  96         :"Ir" (i), "m" (v->counter));                                   \
  97 }                                                                       \
  98
  99 #define ATOMIC64_OP_RETURN(op, asm_op)                                  \
 100 static __inline__ long atomic64_##op##_return_relaxed(long i, atomic64_t * v)   \
 101 {                                                                       \
 102         long temp, result;                                              \
 103         __asm__ __volatile__(                                           \
 104         "1:     ldq_l %0,%1\n"                                          \
 105         "       " #asm_op " %0,%3,%2\n"                                 \
 106         "       " #asm_op " %0,%3,%0\n"                                 \
 107         "       stq_c %0,%1\n"                                          \
 108         "       beq %0,2f\n"                                            \
 109         ".subsection 2\n"                                               \
 110         "2:     br 1b\n"                                                \
 111         ".previous"                                                     \
 112         :"=&r" (temp), "=m" (v->counter), "=&r" (result)                \
 113         :"Ir" (i), "m" (v->counter) : "memory");                        \
 114         return result;                                                  \
 115 }
 116
 117 #define ATOMIC64_FETCH_OP(op, asm_op)                                   \
 118 static __inline__ long atomic64_fetch_##op##_relaxed(long i, atomic64_t * v)    \
 119 {                                                                       \
 120         long temp, result;                                              \
 121         __asm__ __volatile__(                                           \
 122         "1:     ldq_l %2,%1\n"                                          \
 123         "       " #asm_op " %2,%3,%0\n"                                 \
 124         "       stq_c %0,%1\n"                                          \
 125         "       beq %0,2f\n"                                            \
 126         ".subsection 2\n"                                               \
 127         "2:     br 1b\n"                                                \
 128         ".previous"                                                     \
 129         :"=&r" (temp), "=m" (v->counter), "=&r" (result)                \
 130         :"Ir" (i), "m" (v->counter) : "memory");                        \
 131         return result;                                                  \
 132 }
 133
 134 #define ATOMIC_OPS(op)                                                  \
 135         ATOMIC_OP(op, op##l)                                            \
 136         ATOMIC_OP_RETURN(op, op##l)                                     \
 137         ATOMIC_FETCH_OP(op, op##l)                                      \
 138         ATOMIC64_OP(op, op##q)                                          \
 139         ATOMIC64_OP_RETURN(op, op##q)                                   \
 140         ATOMIC64_FETCH_OP(op, op##q)
 141
 142 ATOMIC_OPS(add)
 143 ATOMIC_OPS(sub)
 144
 145 #define atomic_add_return_relaxed       atomic_add_return_relaxed
 146 #define atomic_sub_return_relaxed       atomic_sub_return_relaxed
 147 #define atomic_fetch_add_relaxed        atomic_fetch_add_relaxed
 148 #define atomic_fetch_sub_relaxed        atomic_fetch_sub_relaxed
 149
 150 #define atomic64_add_return_relaxed     atomic64_add_return_relaxed
 151 #define atomic64_sub_return_relaxed     atomic64_sub_return_relaxed
 152 #define atomic64_fetch_add_relaxed      atomic64_fetch_add_relaxed
 153 #define atomic64_fetch_sub_relaxed      atomic64_fetch_sub_relaxed
 154
 155 #define atomic_andnot atomic_andnot
 156 #define atomic64_andnot atomic64_andnot
 157
 158 #undef ATOMIC_OPS
 159 #define ATOMIC_OPS(op, asm)                                             \
 160         ATOMIC_OP(op, asm)                                              \
 161         ATOMIC_FETCH_OP(op, asm)                                        \
 162         ATOMIC64_OP(op, asm)                                            \
 163         ATOMIC64_FETCH_OP(op, asm)
 164
 165 ATOMIC_OPS(and, and)
 166 ATOMIC_OPS(andnot, bic)
 167 ATOMIC_OPS(or, bis)
 168 ATOMIC_OPS(xor, xor)
 169
 170 #define atomic_fetch_and_relaxed        atomic_fetch_and_relaxed
 171 #define atomic_fetch_andnot_relaxed     atomic_fetch_andnot_relaxed
 172 #define atomic_fetch_or_relaxed         atomic_fetch_or_relaxed
 173 #define atomic_fetch_xor_relaxed        atomic_fetch_xor_relaxed
 174
 175 #define atomic64_fetch_and_relaxed      atomic64_fetch_and_relaxed
 176 #define atomic64_fetch_andnot_relaxed   atomic64_fetch_andnot_relaxed
 177 #define atomic64_fetch_or_relaxed       atomic64_fetch_or_relaxed
 178 #define atomic64_fetch_xor_relaxed      atomic64_fetch_xor_relaxed
 179
 180 #undef ATOMIC_OPS
 181 #undef ATOMIC64_FETCH_OP
 182 #undef ATOMIC64_OP_RETURN
 183 #undef ATOMIC64_OP
 184 #undef ATOMIC_FETCH_OP
 185 #undef ATOMIC_OP_RETURN
 186 #undef ATOMIC_OP
 187
 188 #define atomic64_cmpxchg(v, old, new) (cmpxchg(&((v)->counter), old, new))
 189 #define atomic64_xchg(v, new) (xchg(&((v)->counter), new))
 190
 191 #define atomic_cmpxchg(v, old, new) (cmpxchg(&((v)->counter), old, new))
 192 #define atomic_xchg(v, new) (xchg(&((v)->counter), new))
 193
 194 /**
 195  * __atomic_add_unless - add unless the number is a given value
 196  * @v: pointer of type atomic_t
 197  * @a: the amount to add to v...
 198  * @u: ...unless v is equal to u.
 199  *
 200  * Atomically adds @a to @v, so long as it was not @u.
 201  * Returns the old value of @v.
 202  */
 203 static __inline__ int __atomic_add_unless(atomic_t *v, int a, int u)
 204 {
 205         int c, new, old;
 206         smp_mb();
 207         __asm__ __volatile__(
 208         "1:     ldl_l   %[old],%[mem]\n"
 209         "       cmpeq   %[old],%[u],%[c]\n"
 210         "       addl    %[old],%[a],%[new]\n"
 211         "       bne     %[c],2f\n"
 212         "       stl_c   %[new],%[mem]\n"
 213         "       beq     %[new],3f\n"
 214         "2:\n"
 215         ".subsection 2\n"
 216         "3:     br      1b\n"
 217         ".previous"
 218         : [old] "=&r"(old), [new] "=&r"(new), [c] "=&r"(c)
 219         : [mem] "m"(*v), [a] "rI"(a), [u] "rI"((long)u)
 220         : "memory");
 221         smp_mb();
 222         return old;
 223 }
 224
 225
 226 /**
 227  * atomic64_add_unless - add unless the number is a given value
 228  * @v: pointer of type atomic64_t
 229  * @a: the amount to add to v...
 230  * @u: ...unless v is equal to u.
 231  *
 232  * Atomically adds @a to @v, so long as it was not @u.
 233  * Returns true iff @v was not @u.
 234  */
 235 static __inline__ int atomic64_add_unless(atomic64_t *v, long a, long u)
 236 {
 237         long c, tmp;
 238         smp_mb();
 239         __asm__ __volatile__(
 240         "1:     ldq_l   %[tmp],%[mem]\n"
 241         "       cmpeq   %[tmp],%[u],%[c]\n"
 242         "       addq    %[tmp],%[a],%[tmp]\n"
 243         "       bne     %[c],2f\n"
 244         "       stq_c   %[tmp],%[mem]\n"
 245         "       beq     %[tmp],3f\n"
 246         "2:\n"
 247         ".subsection 2\n"
 248         "3:     br      1b\n"
 249         ".previous"
 250         : [tmp] "=&r"(tmp), [c] "=&r"(c)
 251         : [mem] "m"(*v), [a] "rI"(a), [u] "rI"(u)
 252         : "memory");
 253         smp_mb();
 254         return !c;
 255 }
 256
 257 /*
 258  * atomic64_dec_if_positive - decrement by 1 if old value positive
 259  * @v: pointer of type atomic_t
 260  *
 261  * The function returns the old value of *v minus 1, even if
 262  * the atomic variable, v, was not decremented.
 263  */
 264 static inline long atomic64_dec_if_positive(atomic64_t *v)
 265 {
 266         long old, tmp;
 267         smp_mb();
 268         __asm__ __volatile__(
 269         "1:     ldq_l   %[old],%[mem]\n"
 270         "       subq    %[old],1,%[tmp]\n"
 271         "       ble     %[old],2f\n"
 272         "       stq_c   %[tmp],%[mem]\n"
 273         "       beq     %[tmp],3f\n"
 274         "2:\n"
 275         ".subsection 2\n"
 276         "3:     br      1b\n"
 277         ".previous"
 278         : [old] "=&r"(old), [tmp] "=&r"(tmp)
 279         : [mem] "m"(*v)
 280         : "memory");
 281         smp_mb();
 282         return old - 1;
 283 }
 284
 285 #define atomic64_inc_not_zero(v) atomic64_add_unless((v), 1, 0)
 286
 287 #define atomic_add_negative(a, v) (atomic_add_return((a), (v)) < 0)
 288 #define atomic64_add_negative(a, v) (atomic64_add_return((a), (v)) < 0)
 289
 290 #define atomic_dec_return(v) atomic_sub_return(1,(v))
 291 #define atomic64_dec_return(v) atomic64_sub_return(1,(v))
 292
 293 #define atomic_inc_return(v) atomic_add_return(1,(v))
 294 #define atomic64_inc_return(v) atomic64_add_return(1,(v))
 295
 296 #define atomic_sub_and_test(i,v) (atomic_sub_return((i), (v)) == 0)
 297 #define atomic64_sub_and_test(i,v) (atomic64_sub_return((i), (v)) == 0)
 298
 299 #define atomic_inc_and_test(v) (atomic_add_return(1, (v)) == 0)
 300 #define atomic64_inc_and_test(v) (atomic64_add_return(1, (v)) == 0)
 301
 302 #define atomic_dec_and_test(v) (atomic_sub_return(1, (v)) == 0)
 303 #define atomic64_dec_and_test(v) (atomic64_sub_return(1, (v)) == 0)
 304
 305 #define atomic_inc(v) atomic_add(1,(v))
 306 #define atomic64_inc(v) atomic64_add(1,(v))
 307
 308 #define atomic_dec(v) atomic_sub(1,(v))
 309 #define atomic64_dec(v) atomic64_sub(1,(v))
 310
 311 #endif /* _ALPHA_ATOMIC_H */