src/rx/rx_atomic.h

   1 /*
   2  * Copyright (c) 2010 Your Filesystem Inc. All rights reserved.
   3  *
   4  * Redistribution and use in source and binary forms, with or without
   5  * modification, are permitted provided that the following conditions
   6  * are met:
   7  * 1. Redistributions of source code must retain the above copyright
   8  *    notice, this list of conditions and the following disclaimer.
   9  * 2. Redistributions in binary form must reproduce the above copyright
  10  *    notice, this list of conditions and the following disclaimer in the
  11  *    documentation and/or other materials provided with the distribution.
  12  *
  13  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR `AS IS'' AND ANY EXPRESS OR
  14  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  15  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  16  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  17  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  18  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  19  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  20  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  21  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  22  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  23  */
  24
  25 #define RX_ATOMIC_INIT(i) { (i) }
  26
  27 #ifdef AFS_NT40_ENV
  28 typedef struct {
  29     volatile int var;
  30 } rx_atomic_t;
  31
  32 static_inline void
  33 rx_atomic_set(rx_atomic_t *atomic, int val) {
  34     atomic->var = val;
  35 }
  36
  37 static_inline int
  38 rx_atomic_read(rx_atomic_t *atomic) {
  39     return atomic->var;
  40 }
  41
  42 static_inline void
  43 rx_atomic_inc(rx_atomic_t *atomic) {
  44     InterlockedIncrement(&atomic->var);
  45 }
  46
  47 static_inline int
  48 rx_atomic_inc_and_read(rx_atomic_t *atomic) {
  49     return InterlockedIncrement(&atomic->var);
  50 }
  51
  52 static_inline void
  53 rx_atomic_add(rx_atomic_t *atomic, int change) {
  54     InterlockedExchangeAdd(&atomic->var, change);
  55 }
  56
  57 static_inline void
  58 rx_atomic_dec(rx_atomic_t *atomic) {
  59     InterlockedDecrement(&atomic->var);
  60 }
  61
  62 static_inline void
  63 rx_atomic_sub(rx_atomic_t *atomic, int change) {
  64     InterlockedExchangeAdd(&atomic->var, 0 - change);
  65 }
  66
  67 #elif defined(AFS_DARWIN80_ENV) || defined(AFS_USR_DARWIN80_ENV)
  68
  69 #include <libkern/OSAtomic.h>
  70 #if defined(KERNEL) && !defined(UKERNEL)
  71 #define OSAtomicIncrement32 OSIncrementAtomic
  72 #define OSAtomicAdd32 OSAddAtomic
  73 #define OSAtomicDecrement32 OSDecrementAtomic
  74 #endif
  75
  76 typedef struct {
  77     volatile int var;
  78 } rx_atomic_t;
  79
  80 static_inline void
  81 rx_atomic_set(rx_atomic_t *atomic, int val) {
  82     atomic->var = val;
  83 }
  84
  85 static_inline int
  86 rx_atomic_read(rx_atomic_t *atomic) {
  87     return atomic->var;
  88 }
  89
  90 static_inline void
  91 rx_atomic_inc(rx_atomic_t *atomic) {
  92     OSAtomicIncrement32(&atomic->var);
  93 }
  94
  95 static_inline int
  96 rx_atomic_inc_and_read(rx_atomic_t *atomic) {
  97     return OSAtomicIncrement32(&atomic->var);
  98 }
  99
 100 static_inline void
 101 rx_atomic_add(rx_atomic_t *atomic, int change) {
 102     OSAtomicAdd32(change, &atomic->var);
 103 }
 104
 105 static_inline void
 106 rx_atomic_dec(rx_atomic_t *atomic) {
 107     OSAtomicDecrement32(&atomic->var);
 108 }
 109
 110 static_inline void
 111 rx_atomic_sub(rx_atomic_t *atomic, int change) {
 112     OSAtomicAdd32(0 - change, &atomic->var);
 113 }
 114 #elif defined(AFS_LINUX20_ENV) && defined(KERNEL)
 115 #include <asm/atomic.h>
 116
 117 typedef atomic_t rx_atomic_t;
 118
 119 #define rx_atomic_set(X)          atomic_set(X)
 120 #define rx_atomic_read(X)         atomic_read(X)
 121 #define rx_atomic_inc(X)          atomic_inc(X)
 122 #define rx_atomic_inc_and_read(X) atomic_inc_return(X)
 123 #define rx_atomic_add(X, V)       atomic_add(V, X)
 124 #define rx_atomic_dec(X)          atomic_dec(X)
 125 #define rx_atomic_sub(X, V)       atomic_sub(V, X)
 126
 127 #elif defined(AFS_SUN58_ENV)
 128 typedef struct {
 129     volatile int var;
 130 } rx_atomic_t;
 131
 132 static_inline void
 133 rx_atomic_set(rx_atomic_t *atomic, int val) {
 134     atomic->var = val;
 135 }
 136
 137 static_inline int
 138 rx_atomic_read(rx_atomic_t *atomic) {
 139     return atomic->var;
 140 }
 141
 142 static_inline void
 143 rx_atomic_inc(rx_atomic_t *atomic) {
 144     atomic_inc_32(&atomic->var);
 145 }
 146
 147 static_inline int
 148 rx_atomic_inc_and_read(rx_atomic_t *atomic) {
 149     return atomic_inc_32_nv(&atomic->var);
 150 }
 151
 152 static_inline void
 153 rx_atomic_add(rx_atomic_t *atomic, int change) {
 154     atomic_add_32(&atomic->var, change);
 155 }
 156
 157 static_inline void
 158 rx_atomic_dec(rx_atomic_t *atomic) {
 159     atomic_dec_32(&atomic->var);
 160 }
 161
 162 static_inline void
 163 rx_atomic_sub(rx_atomic_t *atomic, int change) {
 164     atomic_add_32(&object, 0 - change);
 165 }
 166
 167 #elif defined(__GNUC__) && defined(HAVE_SYNC_FETCH_AND_ADD)
 168
 169 typedef struct {
 170    volatile int var;
 171 } rx_atomic_t;
 172
 173 static_inline void
 174 rx_atomic_set(rx_atomic_t *atomic, int val) {
 175     atomic->var = val;
 176 }
 177
 178 static_inline int
 179 rx_atomic_read(rx_atomic_t *atomic) {
 180     return atomic->var;
 181 }
 182
 183 static_inline void
 184 rx_atomic_inc(rx_atomic_t *atomic) {
 185     (void)__sync_fetch_and_add(&atomic->var, 1);
 186 }
 187
 188 static_inline int
 189 rx_atomic_inc_and_read(rx_atomic_t *atomic) {
 190     return __sync_add_and_fetch(&atomic->var, 1);
 191 }
 192
 193 static_inline void
 194 rx_atomic_add(rx_atomic_t *atomic, int change) {
 195     (void)__sync_fetch_and_add(&atomic->var, change);
 196 }
 197
 198 static_inline void
 199 rx_atomic_dec(rx_atomic_t *atomic) {
 200     (void)__sync_fetch_and_sub(&atomic->var, 1);
 201 }
 202
 203 static_inline void
 204 rx_atomic_sub(rx_atomic_t *atomic, int change) {
 205     (void)__sync_fetch_and_sub(&atomic->var, change);
 206 }
 207
 208 #else
 209
 210 /* If we're on a platform where we have no idea how to do atomics,
 211  * then we fall back to using a single process wide mutex to protect
 212  * all atomic variables. This won't be the quickest thing ever.
 213  */
 214
 215 #ifdef RX_ENABLE_LOCKS
 216 extern afs_kmutex_t rx_atomic_mutex;
 217 #endif
 218
 219 typedef struct {
 220     int var;
 221 } rx_atomic_t;
 222
 223 static_inline void
 224 rx_atomic_set(rx_atomic_t *atomic, int val) {
 225     MUTEX_ENTER(&rx_atomic_mutex);
 226     atomic->var = val;
 227     MUTEX_EXIT(&rx_atomic_mutex);
 228 }
 229
 230 static_inline int
 231 rx_atomic_read(rx_atomic_t *atomic) {
 232     int out;
 233
 234     MUTEX_ENTER(&rx_atomic_mutex);
 235     out = atomic->var;
 236     MUTEX_EXIT(&rx_atomic_mutex);
 237
 238     return out;
 239 }
 240
 241 static_inline void
 242 rx_atomic_inc(rx_atomic_t *atomic) {
 243    MUTEX_ENTER(&rx_atomic_mutex);
 244    atomic->var++;
 245    MUTEX_EXIT(&rx_atomic_mutex);
 246 }
 247
 248 static_inline int
 249 rx_atomic_inc_and_read(rx_atomic_t *atomic) {
 250     int retval;
 251     MUTEX_ENTER(&rx_atomic_mutex);
 252     atomic->var++;
 253     retval = atomic->var;
 254     MUTEX_EXIT(&rx_atomic_mutex);
 255     return retval;
 256 }
 257
 258 static_inline void
 259 rx_atomic_add(rx_atomic_t *atomic, int change) {
 260     MUTEX_ENTER(&rx_atomic_mutex);
 261     atomic->var += change;
 262     MUTEX_EXIT(&rx_atomic_mutex);
 263 }
 264
 265 static_inline void
 266 rx_atomic_dec(rx_atomic_t *atomic) {
 267     MUTEX_ENTER(&rx_atomic_mutex);
 268     atomic->var--;
 269     MUTEX_EXIT(&rx_atomic_mutex);
 270 }
 271
 272 static_inline void
 273 rx_atomic_sub(rx_atomic_t *atomic, int change) {
 274     MUTEX_ENTER(&rx_atomic_mutex);
 275     atomic->var -= change;
 276     MUTEX_ENTER(&rx_atomic_mutex);
 277 }
 278
 279 #endif