1a4bd5210SJason Evans /* 2a4bd5210SJason Evans ******************************************************************************* 3a4bd5210SJason Evans * Implementation of (2^1+,2) cuckoo hashing, where 2^1+ indicates that each 4a4bd5210SJason Evans * hash bucket contains 2^n cells, for n >= 1, and 2 indicates that two hash 5a4bd5210SJason Evans * functions are employed. The original cuckoo hashing algorithm was described 6a4bd5210SJason Evans * in: 7a4bd5210SJason Evans * 8a4bd5210SJason Evans * Pagh, R., F.F. Rodler (2004) Cuckoo Hashing. Journal of Algorithms 9a4bd5210SJason Evans * 51(2):122-144. 10a4bd5210SJason Evans * 11a4bd5210SJason Evans * Generalization of cuckoo hashing was discussed in: 12a4bd5210SJason Evans * 13a4bd5210SJason Evans * Erlingsson, U., M. Manasse, F. McSherry (2006) A cool and practical 14a4bd5210SJason Evans * alternative to traditional hash tables. In Proceedings of the 7th 15a4bd5210SJason Evans * Workshop on Distributed Data and Structures (WDAS'06), Santa Clara, CA, 16a4bd5210SJason Evans * January 2006. 17a4bd5210SJason Evans * 18a4bd5210SJason Evans * This implementation uses precisely two hash functions because that is the 19a4bd5210SJason Evans * fewest that can work, and supporting multiple hashes is an implementation 20a4bd5210SJason Evans * burden. Here is a reproduction of Figure 1 from Erlingsson et al. (2006) 21a4bd5210SJason Evans * that shows approximate expected maximum load factors for various 22a4bd5210SJason Evans * configurations: 23a4bd5210SJason Evans * 24a4bd5210SJason Evans * | #cells/bucket | 25a4bd5210SJason Evans * #hashes | 1 | 2 | 4 | 8 | 26a4bd5210SJason Evans * --------+-------+-------+-------+-------+ 27a4bd5210SJason Evans * 1 | 0.006 | 0.006 | 0.03 | 0.12 | 28a4bd5210SJason Evans * 2 | 0.49 | 0.86 |>0.93< |>0.96< | 29a4bd5210SJason Evans * 3 | 0.91 | 0.97 | 0.98 | 0.999 | 30a4bd5210SJason Evans * 4 | 0.97 | 0.99 | 0.999 | | 31a4bd5210SJason Evans * 32a4bd5210SJason Evans * The number of cells per bucket is chosen such that a bucket fits in one cache 33a4bd5210SJason Evans * line. So, on 32- and 64-bit systems, we use (8,2) and (4,2) cuckoo hashing, 34a4bd5210SJason Evans * respectively. 35a4bd5210SJason Evans * 36a4bd5210SJason Evans ******************************************************************************/ 37a4bd5210SJason Evans #define JEMALLOC_CKH_C_ 38a4bd5210SJason Evans #include "jemalloc/internal/jemalloc_internal.h" 39a4bd5210SJason Evans 40a4bd5210SJason Evans /******************************************************************************/ 41a4bd5210SJason Evans /* Function prototypes for non-inline static functions. */ 42a4bd5210SJason Evans 43a4bd5210SJason Evans static bool ckh_grow(ckh_t *ckh); 44a4bd5210SJason Evans static void ckh_shrink(ckh_t *ckh); 45a4bd5210SJason Evans 46a4bd5210SJason Evans /******************************************************************************/ 47a4bd5210SJason Evans 48a4bd5210SJason Evans /* 49a4bd5210SJason Evans * Search bucket for key and return the cell number if found; SIZE_T_MAX 50a4bd5210SJason Evans * otherwise. 51a4bd5210SJason Evans */ 52a4bd5210SJason Evans JEMALLOC_INLINE size_t 53a4bd5210SJason Evans ckh_bucket_search(ckh_t *ckh, size_t bucket, const void *key) 54a4bd5210SJason Evans { 55a4bd5210SJason Evans ckhc_t *cell; 56a4bd5210SJason Evans unsigned i; 57a4bd5210SJason Evans 58a4bd5210SJason Evans for (i = 0; i < (ZU(1) << LG_CKH_BUCKET_CELLS); i++) { 59a4bd5210SJason Evans cell = &ckh->tab[(bucket << LG_CKH_BUCKET_CELLS) + i]; 60a4bd5210SJason Evans if (cell->key != NULL && ckh->keycomp(key, cell->key)) 61a4bd5210SJason Evans return ((bucket << LG_CKH_BUCKET_CELLS) + i); 62a4bd5210SJason Evans } 63a4bd5210SJason Evans 64a4bd5210SJason Evans return (SIZE_T_MAX); 65a4bd5210SJason Evans } 66a4bd5210SJason Evans 67a4bd5210SJason Evans /* 68a4bd5210SJason Evans * Search table for key and return cell number if found; SIZE_T_MAX otherwise. 69a4bd5210SJason Evans */ 70a4bd5210SJason Evans JEMALLOC_INLINE size_t 71a4bd5210SJason Evans ckh_isearch(ckh_t *ckh, const void *key) 72a4bd5210SJason Evans { 7388ad2f8dSJason Evans size_t hashes[2], bucket, cell; 74a4bd5210SJason Evans 75a4bd5210SJason Evans assert(ckh != NULL); 76a4bd5210SJason Evans 7788ad2f8dSJason Evans ckh->hash(key, hashes); 78a4bd5210SJason Evans 79a4bd5210SJason Evans /* Search primary bucket. */ 8088ad2f8dSJason Evans bucket = hashes[0] & ((ZU(1) << ckh->lg_curbuckets) - 1); 81a4bd5210SJason Evans cell = ckh_bucket_search(ckh, bucket, key); 82a4bd5210SJason Evans if (cell != SIZE_T_MAX) 83a4bd5210SJason Evans return (cell); 84a4bd5210SJason Evans 85a4bd5210SJason Evans /* Search secondary bucket. */ 8688ad2f8dSJason Evans bucket = hashes[1] & ((ZU(1) << ckh->lg_curbuckets) - 1); 87a4bd5210SJason Evans cell = ckh_bucket_search(ckh, bucket, key); 88a4bd5210SJason Evans return (cell); 89a4bd5210SJason Evans } 90a4bd5210SJason Evans 91a4bd5210SJason Evans JEMALLOC_INLINE bool 92a4bd5210SJason Evans ckh_try_bucket_insert(ckh_t *ckh, size_t bucket, const void *key, 93a4bd5210SJason Evans const void *data) 94a4bd5210SJason Evans { 95a4bd5210SJason Evans ckhc_t *cell; 96a4bd5210SJason Evans unsigned offset, i; 97a4bd5210SJason Evans 98a4bd5210SJason Evans /* 99a4bd5210SJason Evans * Cycle through the cells in the bucket, starting at a random position. 100a4bd5210SJason Evans * The randomness avoids worst-case search overhead as buckets fill up. 101a4bd5210SJason Evans */ 102a4bd5210SJason Evans prng32(offset, LG_CKH_BUCKET_CELLS, ckh->prng_state, CKH_A, CKH_C); 103a4bd5210SJason Evans for (i = 0; i < (ZU(1) << LG_CKH_BUCKET_CELLS); i++) { 104a4bd5210SJason Evans cell = &ckh->tab[(bucket << LG_CKH_BUCKET_CELLS) + 105a4bd5210SJason Evans ((i + offset) & ((ZU(1) << LG_CKH_BUCKET_CELLS) - 1))]; 106a4bd5210SJason Evans if (cell->key == NULL) { 107a4bd5210SJason Evans cell->key = key; 108a4bd5210SJason Evans cell->data = data; 109a4bd5210SJason Evans ckh->count++; 110a4bd5210SJason Evans return (false); 111a4bd5210SJason Evans } 112a4bd5210SJason Evans } 113a4bd5210SJason Evans 114a4bd5210SJason Evans return (true); 115a4bd5210SJason Evans } 116a4bd5210SJason Evans 117a4bd5210SJason Evans /* 118a4bd5210SJason Evans * No space is available in bucket. Randomly evict an item, then try to find an 119a4bd5210SJason Evans * alternate location for that item. Iteratively repeat this 120a4bd5210SJason Evans * eviction/relocation procedure until either success or detection of an 121a4bd5210SJason Evans * eviction/relocation bucket cycle. 122a4bd5210SJason Evans */ 123a4bd5210SJason Evans JEMALLOC_INLINE bool 124a4bd5210SJason Evans ckh_evict_reloc_insert(ckh_t *ckh, size_t argbucket, void const **argkey, 125a4bd5210SJason Evans void const **argdata) 126a4bd5210SJason Evans { 127a4bd5210SJason Evans const void *key, *data, *tkey, *tdata; 128a4bd5210SJason Evans ckhc_t *cell; 12988ad2f8dSJason Evans size_t hashes[2], bucket, tbucket; 130a4bd5210SJason Evans unsigned i; 131a4bd5210SJason Evans 132a4bd5210SJason Evans bucket = argbucket; 133a4bd5210SJason Evans key = *argkey; 134a4bd5210SJason Evans data = *argdata; 135a4bd5210SJason Evans while (true) { 136a4bd5210SJason Evans /* 137a4bd5210SJason Evans * Choose a random item within the bucket to evict. This is 138a4bd5210SJason Evans * critical to correct function, because without (eventually) 139a4bd5210SJason Evans * evicting all items within a bucket during iteration, it 140a4bd5210SJason Evans * would be possible to get stuck in an infinite loop if there 141a4bd5210SJason Evans * were an item for which both hashes indicated the same 142a4bd5210SJason Evans * bucket. 143a4bd5210SJason Evans */ 144a4bd5210SJason Evans prng32(i, LG_CKH_BUCKET_CELLS, ckh->prng_state, CKH_A, CKH_C); 145a4bd5210SJason Evans cell = &ckh->tab[(bucket << LG_CKH_BUCKET_CELLS) + i]; 146a4bd5210SJason Evans assert(cell->key != NULL); 147a4bd5210SJason Evans 148a4bd5210SJason Evans /* Swap cell->{key,data} and {key,data} (evict). */ 149a4bd5210SJason Evans tkey = cell->key; tdata = cell->data; 150a4bd5210SJason Evans cell->key = key; cell->data = data; 151a4bd5210SJason Evans key = tkey; data = tdata; 152a4bd5210SJason Evans 153a4bd5210SJason Evans #ifdef CKH_COUNT 154a4bd5210SJason Evans ckh->nrelocs++; 155a4bd5210SJason Evans #endif 156a4bd5210SJason Evans 157a4bd5210SJason Evans /* Find the alternate bucket for the evicted item. */ 15888ad2f8dSJason Evans ckh->hash(key, hashes); 15988ad2f8dSJason Evans tbucket = hashes[1] & ((ZU(1) << ckh->lg_curbuckets) - 1); 160a4bd5210SJason Evans if (tbucket == bucket) { 16188ad2f8dSJason Evans tbucket = hashes[0] & ((ZU(1) << ckh->lg_curbuckets) 16288ad2f8dSJason Evans - 1); 163a4bd5210SJason Evans /* 164a4bd5210SJason Evans * It may be that (tbucket == bucket) still, if the 165a4bd5210SJason Evans * item's hashes both indicate this bucket. However, 166a4bd5210SJason Evans * we are guaranteed to eventually escape this bucket 167a4bd5210SJason Evans * during iteration, assuming pseudo-random item 168a4bd5210SJason Evans * selection (true randomness would make infinite 169a4bd5210SJason Evans * looping a remote possibility). The reason we can 170a4bd5210SJason Evans * never get trapped forever is that there are two 171a4bd5210SJason Evans * cases: 172a4bd5210SJason Evans * 173a4bd5210SJason Evans * 1) This bucket == argbucket, so we will quickly 174a4bd5210SJason Evans * detect an eviction cycle and terminate. 175a4bd5210SJason Evans * 2) An item was evicted to this bucket from another, 176a4bd5210SJason Evans * which means that at least one item in this bucket 177a4bd5210SJason Evans * has hashes that indicate distinct buckets. 178a4bd5210SJason Evans */ 179a4bd5210SJason Evans } 180a4bd5210SJason Evans /* Check for a cycle. */ 181a4bd5210SJason Evans if (tbucket == argbucket) { 182a4bd5210SJason Evans *argkey = key; 183a4bd5210SJason Evans *argdata = data; 184a4bd5210SJason Evans return (true); 185a4bd5210SJason Evans } 186a4bd5210SJason Evans 187a4bd5210SJason Evans bucket = tbucket; 188a4bd5210SJason Evans if (ckh_try_bucket_insert(ckh, bucket, key, data) == false) 189a4bd5210SJason Evans return (false); 190a4bd5210SJason Evans } 191a4bd5210SJason Evans } 192a4bd5210SJason Evans 193a4bd5210SJason Evans JEMALLOC_INLINE bool 194a4bd5210SJason Evans ckh_try_insert(ckh_t *ckh, void const**argkey, void const**argdata) 195a4bd5210SJason Evans { 19688ad2f8dSJason Evans size_t hashes[2], bucket; 197a4bd5210SJason Evans const void *key = *argkey; 198a4bd5210SJason Evans const void *data = *argdata; 199a4bd5210SJason Evans 20088ad2f8dSJason Evans ckh->hash(key, hashes); 201a4bd5210SJason Evans 202a4bd5210SJason Evans /* Try to insert in primary bucket. */ 20388ad2f8dSJason Evans bucket = hashes[0] & ((ZU(1) << ckh->lg_curbuckets) - 1); 204a4bd5210SJason Evans if (ckh_try_bucket_insert(ckh, bucket, key, data) == false) 205a4bd5210SJason Evans return (false); 206a4bd5210SJason Evans 207a4bd5210SJason Evans /* Try to insert in secondary bucket. */ 20888ad2f8dSJason Evans bucket = hashes[1] & ((ZU(1) << ckh->lg_curbuckets) - 1); 209a4bd5210SJason Evans if (ckh_try_bucket_insert(ckh, bucket, key, data) == false) 210a4bd5210SJason Evans return (false); 211a4bd5210SJason Evans 212a4bd5210SJason Evans /* 213a4bd5210SJason Evans * Try to find a place for this item via iterative eviction/relocation. 214a4bd5210SJason Evans */ 215a4bd5210SJason Evans return (ckh_evict_reloc_insert(ckh, bucket, argkey, argdata)); 216a4bd5210SJason Evans } 217a4bd5210SJason Evans 218a4bd5210SJason Evans /* 219a4bd5210SJason Evans * Try to rebuild the hash table from scratch by inserting all items from the 220a4bd5210SJason Evans * old table into the new. 221a4bd5210SJason Evans */ 222a4bd5210SJason Evans JEMALLOC_INLINE bool 223a4bd5210SJason Evans ckh_rebuild(ckh_t *ckh, ckhc_t *aTab) 224a4bd5210SJason Evans { 225a4bd5210SJason Evans size_t count, i, nins; 226a4bd5210SJason Evans const void *key, *data; 227a4bd5210SJason Evans 228a4bd5210SJason Evans count = ckh->count; 229a4bd5210SJason Evans ckh->count = 0; 230a4bd5210SJason Evans for (i = nins = 0; nins < count; i++) { 231a4bd5210SJason Evans if (aTab[i].key != NULL) { 232a4bd5210SJason Evans key = aTab[i].key; 233a4bd5210SJason Evans data = aTab[i].data; 234a4bd5210SJason Evans if (ckh_try_insert(ckh, &key, &data)) { 235a4bd5210SJason Evans ckh->count = count; 236a4bd5210SJason Evans return (true); 237a4bd5210SJason Evans } 238a4bd5210SJason Evans nins++; 239a4bd5210SJason Evans } 240a4bd5210SJason Evans } 241a4bd5210SJason Evans 242a4bd5210SJason Evans return (false); 243a4bd5210SJason Evans } 244a4bd5210SJason Evans 245a4bd5210SJason Evans static bool 246a4bd5210SJason Evans ckh_grow(ckh_t *ckh) 247a4bd5210SJason Evans { 248a4bd5210SJason Evans bool ret; 249a4bd5210SJason Evans ckhc_t *tab, *ttab; 250a4bd5210SJason Evans size_t lg_curcells; 251a4bd5210SJason Evans unsigned lg_prevbuckets; 252a4bd5210SJason Evans 253a4bd5210SJason Evans #ifdef CKH_COUNT 254a4bd5210SJason Evans ckh->ngrows++; 255a4bd5210SJason Evans #endif 256a4bd5210SJason Evans 257a4bd5210SJason Evans /* 258a4bd5210SJason Evans * It is possible (though unlikely, given well behaved hashes) that the 259a4bd5210SJason Evans * table will have to be doubled more than once in order to create a 260a4bd5210SJason Evans * usable table. 261a4bd5210SJason Evans */ 262a4bd5210SJason Evans lg_prevbuckets = ckh->lg_curbuckets; 263a4bd5210SJason Evans lg_curcells = ckh->lg_curbuckets + LG_CKH_BUCKET_CELLS; 264a4bd5210SJason Evans while (true) { 265a4bd5210SJason Evans size_t usize; 266a4bd5210SJason Evans 267a4bd5210SJason Evans lg_curcells++; 268a4bd5210SJason Evans usize = sa2u(sizeof(ckhc_t) << lg_curcells, CACHELINE); 269a4bd5210SJason Evans if (usize == 0) { 270a4bd5210SJason Evans ret = true; 271a4bd5210SJason Evans goto label_return; 272a4bd5210SJason Evans } 273a4bd5210SJason Evans tab = (ckhc_t *)ipalloc(usize, CACHELINE, true); 274a4bd5210SJason Evans if (tab == NULL) { 275a4bd5210SJason Evans ret = true; 276a4bd5210SJason Evans goto label_return; 277a4bd5210SJason Evans } 278a4bd5210SJason Evans /* Swap in new table. */ 279a4bd5210SJason Evans ttab = ckh->tab; 280a4bd5210SJason Evans ckh->tab = tab; 281a4bd5210SJason Evans tab = ttab; 282a4bd5210SJason Evans ckh->lg_curbuckets = lg_curcells - LG_CKH_BUCKET_CELLS; 283a4bd5210SJason Evans 284a4bd5210SJason Evans if (ckh_rebuild(ckh, tab) == false) { 285a4bd5210SJason Evans idalloc(tab); 286a4bd5210SJason Evans break; 287a4bd5210SJason Evans } 288a4bd5210SJason Evans 289a4bd5210SJason Evans /* Rebuilding failed, so back out partially rebuilt table. */ 290a4bd5210SJason Evans idalloc(ckh->tab); 291a4bd5210SJason Evans ckh->tab = tab; 292a4bd5210SJason Evans ckh->lg_curbuckets = lg_prevbuckets; 293a4bd5210SJason Evans } 294a4bd5210SJason Evans 295a4bd5210SJason Evans ret = false; 296a4bd5210SJason Evans label_return: 297a4bd5210SJason Evans return (ret); 298a4bd5210SJason Evans } 299a4bd5210SJason Evans 300a4bd5210SJason Evans static void 301a4bd5210SJason Evans ckh_shrink(ckh_t *ckh) 302a4bd5210SJason Evans { 303a4bd5210SJason Evans ckhc_t *tab, *ttab; 304a4bd5210SJason Evans size_t lg_curcells, usize; 305a4bd5210SJason Evans unsigned lg_prevbuckets; 306a4bd5210SJason Evans 307a4bd5210SJason Evans /* 308a4bd5210SJason Evans * It is possible (though unlikely, given well behaved hashes) that the 309a4bd5210SJason Evans * table rebuild will fail. 310a4bd5210SJason Evans */ 311a4bd5210SJason Evans lg_prevbuckets = ckh->lg_curbuckets; 312a4bd5210SJason Evans lg_curcells = ckh->lg_curbuckets + LG_CKH_BUCKET_CELLS - 1; 313a4bd5210SJason Evans usize = sa2u(sizeof(ckhc_t) << lg_curcells, CACHELINE); 314a4bd5210SJason Evans if (usize == 0) 315a4bd5210SJason Evans return; 316a4bd5210SJason Evans tab = (ckhc_t *)ipalloc(usize, CACHELINE, true); 317a4bd5210SJason Evans if (tab == NULL) { 318a4bd5210SJason Evans /* 319a4bd5210SJason Evans * An OOM error isn't worth propagating, since it doesn't 320a4bd5210SJason Evans * prevent this or future operations from proceeding. 321a4bd5210SJason Evans */ 322a4bd5210SJason Evans return; 323a4bd5210SJason Evans } 324a4bd5210SJason Evans /* Swap in new table. */ 325a4bd5210SJason Evans ttab = ckh->tab; 326a4bd5210SJason Evans ckh->tab = tab; 327a4bd5210SJason Evans tab = ttab; 328a4bd5210SJason Evans ckh->lg_curbuckets = lg_curcells - LG_CKH_BUCKET_CELLS; 329a4bd5210SJason Evans 330a4bd5210SJason Evans if (ckh_rebuild(ckh, tab) == false) { 331a4bd5210SJason Evans idalloc(tab); 332a4bd5210SJason Evans #ifdef CKH_COUNT 333a4bd5210SJason Evans ckh->nshrinks++; 334a4bd5210SJason Evans #endif 335a4bd5210SJason Evans return; 336a4bd5210SJason Evans } 337a4bd5210SJason Evans 338a4bd5210SJason Evans /* Rebuilding failed, so back out partially rebuilt table. */ 339a4bd5210SJason Evans idalloc(ckh->tab); 340a4bd5210SJason Evans ckh->tab = tab; 341a4bd5210SJason Evans ckh->lg_curbuckets = lg_prevbuckets; 342a4bd5210SJason Evans #ifdef CKH_COUNT 343a4bd5210SJason Evans ckh->nshrinkfails++; 344a4bd5210SJason Evans #endif 345a4bd5210SJason Evans } 346a4bd5210SJason Evans 347a4bd5210SJason Evans bool 348a4bd5210SJason Evans ckh_new(ckh_t *ckh, size_t minitems, ckh_hash_t *hash, ckh_keycomp_t *keycomp) 349a4bd5210SJason Evans { 350a4bd5210SJason Evans bool ret; 351a4bd5210SJason Evans size_t mincells, usize; 352a4bd5210SJason Evans unsigned lg_mincells; 353a4bd5210SJason Evans 354a4bd5210SJason Evans assert(minitems > 0); 355a4bd5210SJason Evans assert(hash != NULL); 356a4bd5210SJason Evans assert(keycomp != NULL); 357a4bd5210SJason Evans 358a4bd5210SJason Evans #ifdef CKH_COUNT 359a4bd5210SJason Evans ckh->ngrows = 0; 360a4bd5210SJason Evans ckh->nshrinks = 0; 361a4bd5210SJason Evans ckh->nshrinkfails = 0; 362a4bd5210SJason Evans ckh->ninserts = 0; 363a4bd5210SJason Evans ckh->nrelocs = 0; 364a4bd5210SJason Evans #endif 365a4bd5210SJason Evans ckh->prng_state = 42; /* Value doesn't really matter. */ 366a4bd5210SJason Evans ckh->count = 0; 367a4bd5210SJason Evans 368a4bd5210SJason Evans /* 369a4bd5210SJason Evans * Find the minimum power of 2 that is large enough to fit aBaseCount 370a4bd5210SJason Evans * entries. We are using (2+,2) cuckoo hashing, which has an expected 371a4bd5210SJason Evans * maximum load factor of at least ~0.86, so 0.75 is a conservative load 372a4bd5210SJason Evans * factor that will typically allow 2^aLgMinItems to fit without ever 373a4bd5210SJason Evans * growing the table. 374a4bd5210SJason Evans */ 375a4bd5210SJason Evans assert(LG_CKH_BUCKET_CELLS > 0); 376a4bd5210SJason Evans mincells = ((minitems + (3 - (minitems % 3))) / 3) << 2; 377a4bd5210SJason Evans for (lg_mincells = LG_CKH_BUCKET_CELLS; 378a4bd5210SJason Evans (ZU(1) << lg_mincells) < mincells; 379a4bd5210SJason Evans lg_mincells++) 380a4bd5210SJason Evans ; /* Do nothing. */ 381a4bd5210SJason Evans ckh->lg_minbuckets = lg_mincells - LG_CKH_BUCKET_CELLS; 382a4bd5210SJason Evans ckh->lg_curbuckets = lg_mincells - LG_CKH_BUCKET_CELLS; 383a4bd5210SJason Evans ckh->hash = hash; 384a4bd5210SJason Evans ckh->keycomp = keycomp; 385a4bd5210SJason Evans 386a4bd5210SJason Evans usize = sa2u(sizeof(ckhc_t) << lg_mincells, CACHELINE); 387a4bd5210SJason Evans if (usize == 0) { 388a4bd5210SJason Evans ret = true; 389a4bd5210SJason Evans goto label_return; 390a4bd5210SJason Evans } 391a4bd5210SJason Evans ckh->tab = (ckhc_t *)ipalloc(usize, CACHELINE, true); 392a4bd5210SJason Evans if (ckh->tab == NULL) { 393a4bd5210SJason Evans ret = true; 394a4bd5210SJason Evans goto label_return; 395a4bd5210SJason Evans } 396a4bd5210SJason Evans 397a4bd5210SJason Evans ret = false; 398a4bd5210SJason Evans label_return: 399a4bd5210SJason Evans return (ret); 400a4bd5210SJason Evans } 401a4bd5210SJason Evans 402a4bd5210SJason Evans void 403a4bd5210SJason Evans ckh_delete(ckh_t *ckh) 404a4bd5210SJason Evans { 405a4bd5210SJason Evans 406a4bd5210SJason Evans assert(ckh != NULL); 407a4bd5210SJason Evans 408a4bd5210SJason Evans #ifdef CKH_VERBOSE 409a4bd5210SJason Evans malloc_printf( 410a4bd5210SJason Evans "%s(%p): ngrows: %"PRIu64", nshrinks: %"PRIu64"," 411a4bd5210SJason Evans " nshrinkfails: %"PRIu64", ninserts: %"PRIu64"," 412a4bd5210SJason Evans " nrelocs: %"PRIu64"\n", __func__, ckh, 413a4bd5210SJason Evans (unsigned long long)ckh->ngrows, 414a4bd5210SJason Evans (unsigned long long)ckh->nshrinks, 415a4bd5210SJason Evans (unsigned long long)ckh->nshrinkfails, 416a4bd5210SJason Evans (unsigned long long)ckh->ninserts, 417a4bd5210SJason Evans (unsigned long long)ckh->nrelocs); 418a4bd5210SJason Evans #endif 419a4bd5210SJason Evans 420a4bd5210SJason Evans idalloc(ckh->tab); 42188ad2f8dSJason Evans if (config_debug) 422a4bd5210SJason Evans memset(ckh, 0x5a, sizeof(ckh_t)); 423a4bd5210SJason Evans } 424a4bd5210SJason Evans 425a4bd5210SJason Evans size_t 426a4bd5210SJason Evans ckh_count(ckh_t *ckh) 427a4bd5210SJason Evans { 428a4bd5210SJason Evans 429a4bd5210SJason Evans assert(ckh != NULL); 430a4bd5210SJason Evans 431a4bd5210SJason Evans return (ckh->count); 432a4bd5210SJason Evans } 433a4bd5210SJason Evans 434a4bd5210SJason Evans bool 435a4bd5210SJason Evans ckh_iter(ckh_t *ckh, size_t *tabind, void **key, void **data) 436a4bd5210SJason Evans { 437a4bd5210SJason Evans size_t i, ncells; 438a4bd5210SJason Evans 439a4bd5210SJason Evans for (i = *tabind, ncells = (ZU(1) << (ckh->lg_curbuckets + 440a4bd5210SJason Evans LG_CKH_BUCKET_CELLS)); i < ncells; i++) { 441a4bd5210SJason Evans if (ckh->tab[i].key != NULL) { 442a4bd5210SJason Evans if (key != NULL) 443a4bd5210SJason Evans *key = (void *)ckh->tab[i].key; 444a4bd5210SJason Evans if (data != NULL) 445a4bd5210SJason Evans *data = (void *)ckh->tab[i].data; 446a4bd5210SJason Evans *tabind = i + 1; 447a4bd5210SJason Evans return (false); 448a4bd5210SJason Evans } 449a4bd5210SJason Evans } 450a4bd5210SJason Evans 451a4bd5210SJason Evans return (true); 452a4bd5210SJason Evans } 453a4bd5210SJason Evans 454a4bd5210SJason Evans bool 455a4bd5210SJason Evans ckh_insert(ckh_t *ckh, const void *key, const void *data) 456a4bd5210SJason Evans { 457a4bd5210SJason Evans bool ret; 458a4bd5210SJason Evans 459a4bd5210SJason Evans assert(ckh != NULL); 460a4bd5210SJason Evans assert(ckh_search(ckh, key, NULL, NULL)); 461a4bd5210SJason Evans 462a4bd5210SJason Evans #ifdef CKH_COUNT 463a4bd5210SJason Evans ckh->ninserts++; 464a4bd5210SJason Evans #endif 465a4bd5210SJason Evans 466a4bd5210SJason Evans while (ckh_try_insert(ckh, &key, &data)) { 467a4bd5210SJason Evans if (ckh_grow(ckh)) { 468a4bd5210SJason Evans ret = true; 469a4bd5210SJason Evans goto label_return; 470a4bd5210SJason Evans } 471a4bd5210SJason Evans } 472a4bd5210SJason Evans 473a4bd5210SJason Evans ret = false; 474a4bd5210SJason Evans label_return: 475a4bd5210SJason Evans return (ret); 476a4bd5210SJason Evans } 477a4bd5210SJason Evans 478a4bd5210SJason Evans bool 479a4bd5210SJason Evans ckh_remove(ckh_t *ckh, const void *searchkey, void **key, void **data) 480a4bd5210SJason Evans { 481a4bd5210SJason Evans size_t cell; 482a4bd5210SJason Evans 483a4bd5210SJason Evans assert(ckh != NULL); 484a4bd5210SJason Evans 485a4bd5210SJason Evans cell = ckh_isearch(ckh, searchkey); 486a4bd5210SJason Evans if (cell != SIZE_T_MAX) { 487a4bd5210SJason Evans if (key != NULL) 488a4bd5210SJason Evans *key = (void *)ckh->tab[cell].key; 489a4bd5210SJason Evans if (data != NULL) 490a4bd5210SJason Evans *data = (void *)ckh->tab[cell].data; 491a4bd5210SJason Evans ckh->tab[cell].key = NULL; 492a4bd5210SJason Evans ckh->tab[cell].data = NULL; /* Not necessary. */ 493a4bd5210SJason Evans 494a4bd5210SJason Evans ckh->count--; 495a4bd5210SJason Evans /* Try to halve the table if it is less than 1/4 full. */ 496a4bd5210SJason Evans if (ckh->count < (ZU(1) << (ckh->lg_curbuckets 497a4bd5210SJason Evans + LG_CKH_BUCKET_CELLS - 2)) && ckh->lg_curbuckets 498a4bd5210SJason Evans > ckh->lg_minbuckets) { 499a4bd5210SJason Evans /* Ignore error due to OOM. */ 500a4bd5210SJason Evans ckh_shrink(ckh); 501a4bd5210SJason Evans } 502a4bd5210SJason Evans 503a4bd5210SJason Evans return (false); 504a4bd5210SJason Evans } 505a4bd5210SJason Evans 506a4bd5210SJason Evans return (true); 507a4bd5210SJason Evans } 508a4bd5210SJason Evans 509a4bd5210SJason Evans bool 510a4bd5210SJason Evans ckh_search(ckh_t *ckh, const void *searchkey, void **key, void **data) 511a4bd5210SJason Evans { 512a4bd5210SJason Evans size_t cell; 513a4bd5210SJason Evans 514a4bd5210SJason Evans assert(ckh != NULL); 515a4bd5210SJason Evans 516a4bd5210SJason Evans cell = ckh_isearch(ckh, searchkey); 517a4bd5210SJason Evans if (cell != SIZE_T_MAX) { 518a4bd5210SJason Evans if (key != NULL) 519a4bd5210SJason Evans *key = (void *)ckh->tab[cell].key; 520a4bd5210SJason Evans if (data != NULL) 521a4bd5210SJason Evans *data = (void *)ckh->tab[cell].data; 522a4bd5210SJason Evans return (false); 523a4bd5210SJason Evans } 524a4bd5210SJason Evans 525a4bd5210SJason Evans return (true); 526a4bd5210SJason Evans } 527a4bd5210SJason Evans 528a4bd5210SJason Evans void 52988ad2f8dSJason Evans ckh_string_hash(const void *key, size_t r_hash[2]) 530a4bd5210SJason Evans { 531a4bd5210SJason Evans 53288ad2f8dSJason Evans hash(key, strlen((const char *)key), 0x94122f33U, r_hash); 533a4bd5210SJason Evans } 534a4bd5210SJason Evans 535a4bd5210SJason Evans bool 536a4bd5210SJason Evans ckh_string_keycomp(const void *k1, const void *k2) 537a4bd5210SJason Evans { 538a4bd5210SJason Evans 539a4bd5210SJason Evans assert(k1 != NULL); 540a4bd5210SJason Evans assert(k2 != NULL); 541a4bd5210SJason Evans 542a4bd5210SJason Evans return (strcmp((char *)k1, (char *)k2) ? false : true); 543a4bd5210SJason Evans } 544a4bd5210SJason Evans 545a4bd5210SJason Evans void 54688ad2f8dSJason Evans ckh_pointer_hash(const void *key, size_t r_hash[2]) 547a4bd5210SJason Evans { 548a4bd5210SJason Evans union { 549a4bd5210SJason Evans const void *v; 55088ad2f8dSJason Evans size_t i; 551a4bd5210SJason Evans } u; 552a4bd5210SJason Evans 553a4bd5210SJason Evans assert(sizeof(u.v) == sizeof(u.i)); 554a4bd5210SJason Evans u.v = key; 55588ad2f8dSJason Evans hash(&u.i, sizeof(u.i), 0xd983396eU, r_hash); 556a4bd5210SJason Evans } 557a4bd5210SJason Evans 558a4bd5210SJason Evans bool 559a4bd5210SJason Evans ckh_pointer_keycomp(const void *k1, const void *k2) 560a4bd5210SJason Evans { 561a4bd5210SJason Evans 562a4bd5210SJason Evans return ((k1 == k2) ? true : false); 563a4bd5210SJason Evans } 564