| 1 | #include "rsync.h" |
| 2 | |
| 3 | #define POOL_DEF_EXTENT (32 * 1024) |
| 4 | |
| 5 | #define POOL_QALIGN_P2 (1<<16) /* power-of-2 qalign */ |
| 6 | |
| 7 | struct alloc_pool |
| 8 | { |
| 9 | size_t size; /* extent size */ |
| 10 | size_t quantum; /* allocation quantum */ |
| 11 | struct pool_extent *extents; /* top extent is "live" */ |
| 12 | void (*bomb)(); /* function to call if |
| 13 | * malloc fails */ |
| 14 | int flags; |
| 15 | |
| 16 | /* statistical data */ |
| 17 | unsigned long e_created; /* extents created */ |
| 18 | unsigned long e_freed; /* extents destroyed */ |
| 19 | int64 n_allocated; /* calls to alloc */ |
| 20 | int64 n_freed; /* calls to free */ |
| 21 | int64 b_allocated; /* cum. bytes allocated */ |
| 22 | int64 b_freed; /* cum. bytes freed */ |
| 23 | }; |
| 24 | |
| 25 | struct pool_extent |
| 26 | { |
| 27 | struct pool_extent *next; |
| 28 | void *start; /* starting address */ |
| 29 | size_t free; /* free bytecount */ |
| 30 | size_t bound; /* trapped free bytes */ |
| 31 | }; |
| 32 | |
| 33 | struct align_test { |
| 34 | uchar foo; |
| 35 | union { |
| 36 | int64 i; |
| 37 | void *p; |
| 38 | } bar; |
| 39 | }; |
| 40 | |
| 41 | #define MINALIGN offsetof(struct align_test, bar) |
| 42 | |
| 43 | /* Temporarily cast a void* var into a char* var when adding an offset (to |
| 44 | * keep some compilers from complaining about the pointer arithmetic). */ |
| 45 | #define PTR_ADD(b,o) ( (void*) ((char*)(b) + (o)) ) |
| 46 | |
| 47 | alloc_pool_t |
| 48 | pool_create(size_t size, size_t quantum, void (*bomb)(const char *), int flags) |
| 49 | { |
| 50 | struct alloc_pool *pool; |
| 51 | |
| 52 | if (!(pool = new0(struct alloc_pool))) |
| 53 | return NULL; |
| 54 | |
| 55 | if ((MINALIGN & (MINALIGN - 1)) != 0) { |
| 56 | if (bomb) |
| 57 | (*bomb)("Compiler error: MINALIGN is not a power of 2\n"); |
| 58 | return NULL; |
| 59 | } |
| 60 | |
| 61 | if (!size) |
| 62 | size = POOL_DEF_EXTENT; |
| 63 | if (!quantum) |
| 64 | quantum = MINALIGN; |
| 65 | |
| 66 | if (flags & POOL_INTERN) { |
| 67 | if (size <= sizeof (struct pool_extent)) |
| 68 | size = quantum; |
| 69 | else |
| 70 | size -= sizeof (struct pool_extent); |
| 71 | flags |= POOL_PREPEND; |
| 72 | } |
| 73 | |
| 74 | if (quantum <= 1) |
| 75 | flags = (flags | POOL_NO_QALIGN) & ~POOL_QALIGN_P2; |
| 76 | else if (!(flags & POOL_NO_QALIGN)) { |
| 77 | if (size % quantum) |
| 78 | size += quantum - size % quantum; |
| 79 | /* If quantum is a power of 2, we'll avoid using modulus. */ |
| 80 | if (!(quantum & (quantum - 1))) |
| 81 | flags |= POOL_QALIGN_P2; |
| 82 | } |
| 83 | |
| 84 | pool->size = size; |
| 85 | pool->quantum = quantum; |
| 86 | pool->bomb = bomb; |
| 87 | pool->flags = flags; |
| 88 | |
| 89 | return pool; |
| 90 | } |
| 91 | |
| 92 | void |
| 93 | pool_destroy(alloc_pool_t p) |
| 94 | { |
| 95 | struct alloc_pool *pool = (struct alloc_pool *) p; |
| 96 | struct pool_extent *cur, *next; |
| 97 | |
| 98 | if (!pool) |
| 99 | return; |
| 100 | |
| 101 | for (cur = pool->extents; cur; cur = next) { |
| 102 | next = cur->next; |
| 103 | if (pool->flags & POOL_PREPEND) |
| 104 | free(PTR_ADD(cur->start, -sizeof (struct pool_extent))); |
| 105 | else { |
| 106 | free(cur->start); |
| 107 | free(cur); |
| 108 | } |
| 109 | } |
| 110 | |
| 111 | free(pool); |
| 112 | } |
| 113 | |
| 114 | void * |
| 115 | pool_alloc(alloc_pool_t p, size_t len, const char *bomb_msg) |
| 116 | { |
| 117 | struct alloc_pool *pool = (struct alloc_pool *) p; |
| 118 | if (!pool) |
| 119 | return NULL; |
| 120 | |
| 121 | if (!len) |
| 122 | len = pool->quantum; |
| 123 | else if (pool->flags & POOL_QALIGN_P2) { |
| 124 | if (len & (pool->quantum - 1)) |
| 125 | len += pool->quantum - (len & (pool->quantum - 1)); |
| 126 | } else if (!(pool->flags & POOL_NO_QALIGN)) { |
| 127 | if (len % pool->quantum) |
| 128 | len += pool->quantum - len % pool->quantum; |
| 129 | } |
| 130 | |
| 131 | if (len > pool->size) |
| 132 | goto bomb_out; |
| 133 | |
| 134 | if (!pool->extents || len > pool->extents->free) { |
| 135 | void *start; |
| 136 | size_t asize; |
| 137 | struct pool_extent *ext; |
| 138 | |
| 139 | asize = pool->size; |
| 140 | if (pool->flags & POOL_PREPEND) |
| 141 | asize += sizeof (struct pool_extent); |
| 142 | |
| 143 | if (!(start = new_array(char, asize))) |
| 144 | goto bomb_out; |
| 145 | |
| 146 | if (pool->flags & POOL_CLEAR) |
| 147 | memset(start, 0, asize); |
| 148 | |
| 149 | if (pool->flags & POOL_PREPEND) { |
| 150 | ext = start; |
| 151 | start = PTR_ADD(start, sizeof (struct pool_extent)); |
| 152 | } else if (!(ext = new(struct pool_extent))) |
| 153 | goto bomb_out; |
| 154 | ext->start = start; |
| 155 | ext->free = pool->size; |
| 156 | ext->bound = 0; |
| 157 | ext->next = pool->extents; |
| 158 | pool->extents = ext; |
| 159 | |
| 160 | pool->e_created++; |
| 161 | } |
| 162 | |
| 163 | pool->n_allocated++; |
| 164 | pool->b_allocated += len; |
| 165 | |
| 166 | pool->extents->free -= len; |
| 167 | |
| 168 | return PTR_ADD(pool->extents->start, pool->extents->free); |
| 169 | |
| 170 | bomb_out: |
| 171 | if (pool->bomb) |
| 172 | (*pool->bomb)(bomb_msg); |
| 173 | return NULL; |
| 174 | } |
| 175 | |
| 176 | /* This function allows you to declare memory in the pool that you are done |
| 177 | * using. If you free all the memory in a pool's extent, that extent will |
| 178 | * be freed. */ |
| 179 | void |
| 180 | pool_free(alloc_pool_t p, size_t len, void *addr) |
| 181 | { |
| 182 | struct alloc_pool *pool = (struct alloc_pool *)p; |
| 183 | struct pool_extent *cur, *prev; |
| 184 | |
| 185 | if (!pool) |
| 186 | return; |
| 187 | |
| 188 | if (!addr) { |
| 189 | /* A NULL addr starts a fresh extent for new allocations. */ |
| 190 | if ((cur = pool->extents) != NULL && cur->free != pool->size) { |
| 191 | cur->bound += cur->free; |
| 192 | cur->free = 0; |
| 193 | } |
| 194 | return; |
| 195 | } |
| 196 | |
| 197 | if (!len) |
| 198 | len = pool->quantum; |
| 199 | else if (pool->flags & POOL_QALIGN_P2) { |
| 200 | if (len & (pool->quantum - 1)) |
| 201 | len += pool->quantum - (len & (pool->quantum - 1)); |
| 202 | } else if (!(pool->flags & POOL_NO_QALIGN)) { |
| 203 | if (len % pool->quantum) |
| 204 | len += pool->quantum - len % pool->quantum; |
| 205 | } |
| 206 | |
| 207 | pool->n_freed++; |
| 208 | pool->b_freed += len; |
| 209 | |
| 210 | for (prev = NULL, cur = pool->extents; cur; prev = cur, cur = cur->next) { |
| 211 | if (addr >= cur->start |
| 212 | && addr < PTR_ADD(cur->start, pool->size)) |
| 213 | break; |
| 214 | } |
| 215 | if (!cur) |
| 216 | return; |
| 217 | |
| 218 | if (!prev) { |
| 219 | /* The "live" extent is kept ready for more allocations. */ |
| 220 | if (cur->free + cur->bound + len >= pool->size) { |
| 221 | if (pool->flags & POOL_CLEAR) { |
| 222 | memset(PTR_ADD(cur->start, cur->free), 0, |
| 223 | pool->size - cur->free); |
| 224 | } |
| 225 | cur->free = pool->size; |
| 226 | cur->bound = 0; |
| 227 | } else if (addr == PTR_ADD(cur->start, cur->free)) { |
| 228 | if (pool->flags & POOL_CLEAR) |
| 229 | memset(addr, 0, len); |
| 230 | cur->free += len; |
| 231 | } else |
| 232 | cur->bound += len; |
| 233 | } else { |
| 234 | cur->bound += len; |
| 235 | |
| 236 | if (cur->free + cur->bound >= pool->size) { |
| 237 | prev->next = cur->next; |
| 238 | if (pool->flags & POOL_PREPEND) |
| 239 | free(PTR_ADD(cur->start, -sizeof (struct pool_extent))); |
| 240 | else { |
| 241 | free(cur->start); |
| 242 | free(cur); |
| 243 | } |
| 244 | pool->e_freed++; |
| 245 | } else if (prev != pool->extents) { |
| 246 | /* Move the extent to be the first non-live extent. */ |
| 247 | prev->next = cur->next; |
| 248 | cur->next = pool->extents->next; |
| 249 | pool->extents->next = cur; |
| 250 | } |
| 251 | } |
| 252 | } |
| 253 | |
| 254 | /* This allows you to declare that the given address marks the edge of some |
| 255 | * pool memory that is no longer needed. Any extents that hold only data |
| 256 | * older than the boundary address are freed. NOTE: You MUST NOT USE BOTH |
| 257 | * pool_free() and pool_free_old() on the same pool!! */ |
| 258 | void |
| 259 | pool_free_old(alloc_pool_t p, void *addr) |
| 260 | { |
| 261 | struct alloc_pool *pool = (struct alloc_pool *)p; |
| 262 | struct pool_extent *cur, *prev, *next; |
| 263 | |
| 264 | if (!pool || !addr) |
| 265 | return; |
| 266 | |
| 267 | for (prev = NULL, cur = pool->extents; cur; prev = cur, cur = cur->next) { |
| 268 | if (addr >= cur->start |
| 269 | && addr < PTR_ADD(cur->start, pool->size)) |
| 270 | break; |
| 271 | } |
| 272 | if (!cur) |
| 273 | return; |
| 274 | |
| 275 | if (addr == PTR_ADD(cur->start, cur->free)) { |
| 276 | if (prev) { |
| 277 | prev->next = NULL; |
| 278 | next = cur; |
| 279 | } else { |
| 280 | /* The most recent live extent can just be reset. */ |
| 281 | if (pool->flags & POOL_CLEAR) |
| 282 | memset(addr, 0, pool->size - cur->free); |
| 283 | cur->free = pool->size; |
| 284 | cur->bound = 0; |
| 285 | next = cur->next; |
| 286 | cur->next = NULL; |
| 287 | } |
| 288 | } else { |
| 289 | next = cur->next; |
| 290 | cur->next = NULL; |
| 291 | } |
| 292 | |
| 293 | while ((cur = next) != NULL) { |
| 294 | next = cur->next; |
| 295 | if (pool->flags & POOL_PREPEND) |
| 296 | free(PTR_ADD(cur->start, -sizeof (struct pool_extent))); |
| 297 | else { |
| 298 | free(cur->start); |
| 299 | free(cur); |
| 300 | } |
| 301 | pool->e_freed++; |
| 302 | } |
| 303 | } |
| 304 | |
| 305 | /* If the current extent doesn't have "len" free space in it, mark it as full |
| 306 | * so that the next alloc will start a new extent. If len is (size_t)-1, this |
| 307 | * bump will always occur. The function returns a boundary address that can |
| 308 | * be used with pool_free_old(), or a NULL if no memory is allocated. */ |
| 309 | void * |
| 310 | pool_boundary(alloc_pool_t p, size_t len) |
| 311 | { |
| 312 | struct alloc_pool *pool = (struct alloc_pool *)p; |
| 313 | struct pool_extent *cur; |
| 314 | |
| 315 | if (!pool || !pool->extents) |
| 316 | return NULL; |
| 317 | |
| 318 | cur = pool->extents; |
| 319 | |
| 320 | if (cur->free < len) { |
| 321 | cur->bound += cur->free; |
| 322 | cur->free = 0; |
| 323 | } |
| 324 | |
| 325 | return PTR_ADD(cur->start, cur->free); |
| 326 | } |
| 327 | |
| 328 | #define FDPRINT(label, value) \ |
| 329 | snprintf(buf, sizeof buf, label, value), \ |
| 330 | write(fd, buf, strlen(buf)) |
| 331 | |
| 332 | #define FDEXTSTAT(ext) \ |
| 333 | snprintf(buf, sizeof buf, " %12ld %5ld\n", \ |
| 334 | (long) ext->free, \ |
| 335 | (long) ext->bound), \ |
| 336 | write(fd, buf, strlen(buf)) |
| 337 | |
| 338 | void |
| 339 | pool_stats(alloc_pool_t p, int fd, int summarize) |
| 340 | { |
| 341 | struct alloc_pool *pool = (struct alloc_pool *) p; |
| 342 | struct pool_extent *cur; |
| 343 | char buf[BUFSIZ]; |
| 344 | |
| 345 | if (!pool) |
| 346 | return; |
| 347 | |
| 348 | FDPRINT(" Extent size: %12ld\n", (long) pool->size); |
| 349 | FDPRINT(" Alloc quantum: %12ld\n", (long) pool->quantum); |
| 350 | FDPRINT(" Extents created: %12ld\n", pool->e_created); |
| 351 | FDPRINT(" Extents freed: %12ld\n", pool->e_freed); |
| 352 | FDPRINT(" Alloc count: %12.0f\n", (double) pool->n_allocated); |
| 353 | FDPRINT(" Free Count: %12.0f\n", (double) pool->n_freed); |
| 354 | FDPRINT(" Bytes allocated: %12.0f\n", (double) pool->b_allocated); |
| 355 | FDPRINT(" Bytes freed: %12.0f\n", (double) pool->b_freed); |
| 356 | |
| 357 | if (summarize) |
| 358 | return; |
| 359 | |
| 360 | if (!pool->extents) |
| 361 | return; |
| 362 | |
| 363 | write(fd, "\n", 1); |
| 364 | |
| 365 | for (cur = pool->extents; cur; cur = cur->next) |
| 366 | FDEXTSTAT(cur); |
| 367 | } |