lib/librte_hash/rte_cuckoo_hash.c

   1 /* SPDX-License-Identifier: BSD-3-Clause
   2  * Copyright(c) 2010-2016 Intel Corporation
   3  */
   4
   5 #include <string.h>
   6 #include <stdint.h>
   7 #include <errno.h>
   8 #include <stdio.h>
   9 #include <stdarg.h>
  10 #include <sys/queue.h>
  11
  12 #include <rte_common.h>
  13 #include <rte_memory.h>         /* for definition of RTE_CACHE_LINE_SIZE */
  14 #include <rte_log.h>
  15 #include <rte_memcpy.h>
  16 #include <rte_prefetch.h>
  17 #include <rte_branch_prediction.h>
  18 #include <rte_malloc.h>
  19 #include <rte_eal.h>
  20 #include <rte_eal_memconfig.h>
  21 #include <rte_per_lcore.h>
  22 #include <rte_errno.h>
  23 #include <rte_string_fns.h>
  24 #include <rte_cpuflags.h>
  25 #include <rte_rwlock.h>
  26 #include <rte_spinlock.h>
  27 #include <rte_ring.h>
  28 #include <rte_compat.h>
  29 #include <rte_pause.h>
  30
  31 #include "rte_hash.h"
  32 #include "rte_cuckoo_hash.h"
  33
  34 #if defined(RTE_ARCH_X86)
  35 #include "rte_cuckoo_hash_x86.h"
  36 #endif
  37
  38 TAILQ_HEAD(rte_hash_list, rte_tailq_entry);
  39
  40 static struct rte_tailq_elem rte_hash_tailq = {
  41         .name = "RTE_HASH",
  42 };
  43 EAL_REGISTER_TAILQ(rte_hash_tailq)
  44
  45 struct rte_hash *
  46 rte_hash_find_existing(const char *name)
  47 {
  48         struct rte_hash *h = NULL;
  49         struct rte_tailq_entry *te;
  50         struct rte_hash_list *hash_list;
  51
  52         hash_list = RTE_TAILQ_CAST(rte_hash_tailq.head, rte_hash_list);
  53
  54         rte_rwlock_read_lock(RTE_EAL_TAILQ_RWLOCK);
  55         TAILQ_FOREACH(te, hash_list, next) {
  56                 h = (struct rte_hash *) te->data;
  57                 if (strncmp(name, h->name, RTE_HASH_NAMESIZE) == 0)
  58                         break;
  59         }
  60         rte_rwlock_read_unlock(RTE_EAL_TAILQ_RWLOCK);
  61
  62         if (te == NULL) {
  63                 rte_errno = ENOENT;
  64                 return NULL;
  65         }
  66         return h;
  67 }
  68
  69 void rte_hash_set_cmp_func(struct rte_hash *h, rte_hash_cmp_eq_t func)
  70 {
  71         h->cmp_jump_table_idx = KEY_CUSTOM;
  72         h->rte_hash_custom_cmp_eq = func;
  73 }
  74
  75 static inline int
  76 rte_hash_cmp_eq(const void *key1, const void *key2, const struct rte_hash *h)
  77 {
  78         if (h->cmp_jump_table_idx == KEY_CUSTOM)
  79                 return h->rte_hash_custom_cmp_eq(key1, key2, h->key_len);
  80         else
  81                 return cmp_jump_table[h->cmp_jump_table_idx](key1, key2, h->key_len);
  82 }
  83
  84 struct rte_hash *
  85 rte_hash_create(const struct rte_hash_parameters *params)
  86 {
  87         struct rte_hash *h = NULL;
  88         struct rte_tailq_entry *te = NULL;
  89         struct rte_hash_list *hash_list;
  90         struct rte_ring *r = NULL;
  91         char hash_name[RTE_HASH_NAMESIZE];
  92         void *k = NULL;
  93         void *buckets = NULL;
  94         char ring_name[RTE_RING_NAMESIZE];
  95         unsigned num_key_slots;
  96         unsigned hw_trans_mem_support = 0;
  97         unsigned i;
  98         rte_hash_function default_hash_func = (rte_hash_function)rte_jhash;
  99
 100         hash_list = RTE_TAILQ_CAST(rte_hash_tailq.head, rte_hash_list);
 101
 102         if (params == NULL) {
 103                 RTE_LOG(ERR, HASH, "rte_hash_create has no parameters\n");
 104                 return NULL;
 105         }
 106
 107         /* Check for valid parameters */
 108         if ((params->entries > RTE_HASH_ENTRIES_MAX) ||
 109                         (params->entries < RTE_HASH_BUCKET_ENTRIES) ||
 110                         (params->key_len == 0)) {
 111                 rte_errno = EINVAL;
 112                 RTE_LOG(ERR, HASH, "rte_hash_create has invalid parameters\n");
 113                 return NULL;
 114         }
 115
 116         /* Check extra flags field to check extra options. */
 117         if (params->extra_flag & RTE_HASH_EXTRA_FLAGS_TRANS_MEM_SUPPORT)
 118                 hw_trans_mem_support = 1;
 119
 120         /* Store all keys and leave the first entry as a dummy entry for lookup_bulk */
 121         if (hw_trans_mem_support)
 122                 /*
 123                  * Increase number of slots by total number of indices
 124                  * that can be stored in the lcore caches
 125                  * except for the first cache
 126                  */
 127                 num_key_slots = params->entries + (RTE_MAX_LCORE - 1) *
 128                                         (LCORE_CACHE_SIZE - 1) + 1;
 129         else
 130                 num_key_slots = params->entries + 1;
 131
 132         snprintf(ring_name, sizeof(ring_name), "HT_%s", params->name);
 133         /* Create ring (Dummy slot index is not enqueued) */
 134         r = rte_ring_create(ring_name, rte_align32pow2(num_key_slots),
 135                         params->socket_id, 0);
 136         if (r == NULL) {
 137                 RTE_LOG(ERR, HASH, "memory allocation failed\n");
 138                 goto err;
 139         }
 140
 141         snprintf(hash_name, sizeof(hash_name), "HT_%s", params->name);
 142
 143         rte_rwlock_write_lock(RTE_EAL_TAILQ_RWLOCK);
 144
 145         /* guarantee there's no existing: this is normally already checked
 146          * by ring creation above */
 147         TAILQ_FOREACH(te, hash_list, next) {
 148                 h = (struct rte_hash *) te->data;
 149                 if (strncmp(params->name, h->name, RTE_HASH_NAMESIZE) == 0)
 150                         break;
 151         }
 152         h = NULL;
 153         if (te != NULL) {
 154                 rte_errno = EEXIST;
 155                 te = NULL;
 156                 goto err_unlock;
 157         }
 158
 159         te = rte_zmalloc("HASH_TAILQ_ENTRY", sizeof(*te), 0);
 160         if (te == NULL) {
 161                 RTE_LOG(ERR, HASH, "tailq entry allocation failed\n");
 162                 goto err_unlock;
 163         }
 164
 165         h = (struct rte_hash *)rte_zmalloc_socket(hash_name, sizeof(struct rte_hash),
 166                                         RTE_CACHE_LINE_SIZE, params->socket_id);
 167
 168         if (h == NULL) {
 169                 RTE_LOG(ERR, HASH, "memory allocation failed\n");
 170                 goto err_unlock;
 171         }
 172
 173         const uint32_t num_buckets = rte_align32pow2(params->entries)
 174                                         / RTE_HASH_BUCKET_ENTRIES;
 175
 176         buckets = rte_zmalloc_socket(NULL,
 177                                 num_buckets * sizeof(struct rte_hash_bucket),
 178                                 RTE_CACHE_LINE_SIZE, params->socket_id);
 179
 180         if (buckets == NULL) {
 181                 RTE_LOG(ERR, HASH, "memory allocation failed\n");
 182                 goto err_unlock;
 183         }
 184
 185         const uint32_t key_entry_size = sizeof(struct rte_hash_key) + params->key_len;
 186         const uint64_t key_tbl_size = (uint64_t) key_entry_size * num_key_slots;
 187
 188         k = rte_zmalloc_socket(NULL, key_tbl_size,
 189                         RTE_CACHE_LINE_SIZE, params->socket_id);
 190
 191         if (k == NULL) {
 192                 RTE_LOG(ERR, HASH, "memory allocation failed\n");
 193                 goto err_unlock;
 194         }
 195
 196 /*
 197  * If x86 architecture is used, select appropriate compare function,
 198  * which may use x86 intrinsics, otherwise use memcmp
 199  */
 200 #if defined(RTE_ARCH_X86) || defined(RTE_ARCH_ARM64)
 201         /* Select function to compare keys */
 202         switch (params->key_len) {
 203         case 16:
 204                 h->cmp_jump_table_idx = KEY_16_BYTES;
 205                 break;
 206         case 32:
 207                 h->cmp_jump_table_idx = KEY_32_BYTES;
 208                 break;
 209         case 48:
 210                 h->cmp_jump_table_idx = KEY_48_BYTES;
 211                 break;
 212         case 64:
 213                 h->cmp_jump_table_idx = KEY_64_BYTES;
 214                 break;
 215         case 80:
 216                 h->cmp_jump_table_idx = KEY_80_BYTES;
 217                 break;
 218         case 96:
 219                 h->cmp_jump_table_idx = KEY_96_BYTES;
 220                 break;
 221         case 112:
 222                 h->cmp_jump_table_idx = KEY_112_BYTES;
 223                 break;
 224         case 128:
 225                 h->cmp_jump_table_idx = KEY_128_BYTES;
 226                 break;
 227         default:
 228                 /* If key is not multiple of 16, use generic memcmp */
 229                 h->cmp_jump_table_idx = KEY_OTHER_BYTES;
 230         }
 231 #else
 232         h->cmp_jump_table_idx = KEY_OTHER_BYTES;
 233 #endif
 234
 235         if (hw_trans_mem_support) {
 236                 h->local_free_slots = rte_zmalloc_socket(NULL,
 237                                 sizeof(struct lcore_cache) * RTE_MAX_LCORE,
 238                                 RTE_CACHE_LINE_SIZE, params->socket_id);
 239         }
 240
 241         /* Default hash function */
 242 #if defined(RTE_ARCH_X86)
 243         default_hash_func = (rte_hash_function)rte_hash_crc;
 244 #elif defined(RTE_ARCH_ARM64)
 245         if (rte_cpu_get_flag_enabled(RTE_CPUFLAG_CRC32))
 246                 default_hash_func = (rte_hash_function)rte_hash_crc;
 247 #endif
 248         /* Setup hash context */
 249         snprintf(h->name, sizeof(h->name), "%s", params->name);
 250         h->entries = params->entries;
 251         h->key_len = params->key_len;
 252         h->key_entry_size = key_entry_size;
 253         h->hash_func_init_val = params->hash_func_init_val;
 254
 255         h->num_buckets = num_buckets;
 256         h->bucket_bitmask = h->num_buckets - 1;
 257         h->buckets = buckets;
 258         h->hash_func = (params->hash_func == NULL) ?
 259                 default_hash_func : params->hash_func;
 260         h->key_store = k;
 261         h->free_slots = r;
 262         h->hw_trans_mem_support = hw_trans_mem_support;
 263
 264 #if defined(RTE_ARCH_X86)
 265         if (rte_cpu_get_flag_enabled(RTE_CPUFLAG_AVX2))
 266                 h->sig_cmp_fn = RTE_HASH_COMPARE_AVX2;
 267         else if (rte_cpu_get_flag_enabled(RTE_CPUFLAG_SSE2))
 268                 h->sig_cmp_fn = RTE_HASH_COMPARE_SSE;
 269         else
 270 #endif
 271                 h->sig_cmp_fn = RTE_HASH_COMPARE_SCALAR;
 272
 273         /* Turn on multi-writer only with explicit flat from user and TM
 274          * support.
 275          */
 276         if (params->extra_flag & RTE_HASH_EXTRA_FLAGS_MULTI_WRITER_ADD) {
 277                 if (h->hw_trans_mem_support) {
 278                         h->add_key = ADD_KEY_MULTIWRITER_TM;
 279                 } else {
 280                         h->add_key = ADD_KEY_MULTIWRITER;
 281                         h->multiwriter_lock = rte_malloc(NULL,
 282                                                         sizeof(rte_spinlock_t),
 283                                                         RTE_CACHE_LINE_SIZE);
 284                         if (h->multiwriter_lock == NULL)
 285                                 goto err_unlock;
 286
 287                         rte_spinlock_init(h->multiwriter_lock);
 288                 }
 289         } else
 290                 h->add_key = ADD_KEY_SINGLEWRITER;
 291
 292         /* Populate free slots ring. Entry zero is reserved for key misses. */
 293         for (i = 1; i < num_key_slots; i++)
 294                 rte_ring_sp_enqueue(r, (void *)((uintptr_t) i));
 295
 296         te->data = (void *) h;
 297         TAILQ_INSERT_TAIL(hash_list, te, next);
 298         rte_rwlock_write_unlock(RTE_EAL_TAILQ_RWLOCK);
 299
 300         return h;
 301 err_unlock:
 302         rte_rwlock_write_unlock(RTE_EAL_TAILQ_RWLOCK);
 303 err:
 304         rte_ring_free(r);
 305         rte_free(te);
 306         rte_free(h);
 307         rte_free(buckets);
 308         rte_free(k);
 309         return NULL;
 310 }
 311
 312 void
 313 rte_hash_free(struct rte_hash *h)
 314 {
 315         struct rte_tailq_entry *te;
 316         struct rte_hash_list *hash_list;
 317
 318         if (h == NULL)
 319                 return;
 320
 321         hash_list = RTE_TAILQ_CAST(rte_hash_tailq.head, rte_hash_list);
 322
 323         rte_rwlock_write_lock(RTE_EAL_TAILQ_RWLOCK);
 324
 325         /* find out tailq entry */
 326         TAILQ_FOREACH(te, hash_list, next) {
 327                 if (te->data == (void *) h)
 328                         break;
 329         }
 330
 331         if (te == NULL) {
 332                 rte_rwlock_write_unlock(RTE_EAL_TAILQ_RWLOCK);
 333                 return;
 334         }
 335
 336         TAILQ_REMOVE(hash_list, te, next);
 337
 338         rte_rwlock_write_unlock(RTE_EAL_TAILQ_RWLOCK);
 339
 340         if (h->hw_trans_mem_support)
 341                 rte_free(h->local_free_slots);
 342
 343         if (h->add_key == ADD_KEY_MULTIWRITER)
 344                 rte_free(h->multiwriter_lock);
 345         rte_ring_free(h->free_slots);
 346         rte_free(h->key_store);
 347         rte_free(h->buckets);
 348         rte_free(h);
 349         rte_free(te);
 350 }
 351
 352 hash_sig_t
 353 rte_hash_hash(const struct rte_hash *h, const void *key)
 354 {
 355         /* calc hash result by key */
 356         return h->hash_func(key, h->key_len, h->hash_func_init_val);
 357 }
 358
 359 /* Calc the secondary hash value from the primary hash value of a given key */
 360 static inline hash_sig_t
 361 rte_hash_secondary_hash(const hash_sig_t primary_hash)
 362 {
 363         static const unsigned all_bits_shift = 12;
 364         static const unsigned alt_bits_xor = 0x5bd1e995;
 365
 366         uint32_t tag = primary_hash >> all_bits_shift;
 367
 368         return primary_hash ^ ((tag + 1) * alt_bits_xor);
 369 }
 370
 371 void
 372 rte_hash_reset(struct rte_hash *h)
 373 {
 374         void *ptr;
 375         uint32_t tot_ring_cnt, i;
 376
 377         if (h == NULL)
 378                 return;
 379
 380         memset(h->buckets, 0, h->num_buckets * sizeof(struct rte_hash_bucket));
 381         memset(h->key_store, 0, h->key_entry_size * (h->entries + 1));
 382
 383         /* clear the free ring */
 384         while (rte_ring_dequeue(h->free_slots, &ptr) == 0)
 385                 rte_pause();
 386
 387         /* Repopulate the free slots ring. Entry zero is reserved for key misses */
 388         if (h->hw_trans_mem_support)
 389                 tot_ring_cnt = h->entries + (RTE_MAX_LCORE - 1) *
 390                                         (LCORE_CACHE_SIZE - 1);
 391         else
 392                 tot_ring_cnt = h->entries;
 393
 394         for (i = 1; i < tot_ring_cnt + 1; i++)
 395                 rte_ring_sp_enqueue(h->free_slots, (void *)((uintptr_t) i));
 396
 397         if (h->hw_trans_mem_support) {
 398                 /* Reset local caches per lcore */
 399                 for (i = 0; i < RTE_MAX_LCORE; i++)
 400                         h->local_free_slots[i].len = 0;
 401         }
 402 }
 403
 404 /* Search for an entry that can be pushed to its alternative location */
 405 static inline int
 406 make_space_bucket(const struct rte_hash *h, struct rte_hash_bucket *bkt,
 407                 unsigned int *nr_pushes)
 408 {
 409         unsigned i, j;
 410         int ret;
 411         uint32_t next_bucket_idx;
 412         struct rte_hash_bucket *next_bkt[RTE_HASH_BUCKET_ENTRIES];
 413
 414         /*
 415          * Push existing item (search for bucket with space in
 416          * alternative locations) to its alternative location
 417          */
 418         for (i = 0; i < RTE_HASH_BUCKET_ENTRIES; i++) {
 419                 /* Search for space in alternative locations */
 420                 next_bucket_idx = bkt->sig_alt[i] & h->bucket_bitmask;
 421                 next_bkt[i] = &h->buckets[next_bucket_idx];
 422                 for (j = 0; j < RTE_HASH_BUCKET_ENTRIES; j++) {
 423                         if (next_bkt[i]->key_idx[j] == EMPTY_SLOT)
 424                                 break;
 425                 }
 426
 427                 if (j != RTE_HASH_BUCKET_ENTRIES)
 428                         break;
 429         }
 430
 431         /* Alternative location has spare room (end of recursive function) */
 432         if (i != RTE_HASH_BUCKET_ENTRIES) {
 433                 next_bkt[i]->sig_alt[j] = bkt->sig_current[i];
 434                 next_bkt[i]->sig_current[j] = bkt->sig_alt[i];
 435                 next_bkt[i]->key_idx[j] = bkt->key_idx[i];
 436                 return i;
 437         }
 438
 439         /* Pick entry that has not been pushed yet */
 440         for (i = 0; i < RTE_HASH_BUCKET_ENTRIES; i++)
 441                 if (bkt->flag[i] == 0)
 442                         break;
 443
 444         /* All entries have been pushed, so entry cannot be added */
 445         if (i == RTE_HASH_BUCKET_ENTRIES || ++(*nr_pushes) > RTE_HASH_MAX_PUSHES)
 446                 return -ENOSPC;
 447
 448         /* Set flag to indicate that this entry is going to be pushed */
 449         bkt->flag[i] = 1;
 450
 451         /* Need room in alternative bucket to insert the pushed entry */
 452         ret = make_space_bucket(h, next_bkt[i], nr_pushes);
 453         /*
 454          * After recursive function.
 455          * Clear flags and insert the pushed entry
 456          * in its alternative location if successful,
 457          * or return error
 458          */
 459         bkt->flag[i] = 0;
 460         if (ret >= 0) {
 461                 next_bkt[i]->sig_alt[ret] = bkt->sig_current[i];
 462                 next_bkt[i]->sig_current[ret] = bkt->sig_alt[i];
 463                 next_bkt[i]->key_idx[ret] = bkt->key_idx[i];
 464                 return i;
 465         } else
 466                 return ret;
 467
 468 }
 469
 470 /*
 471  * Function called to enqueue back an index in the cache/ring,
 472  * as slot has not being used and it can be used in the
 473  * next addition attempt.
 474  */
 475 static inline void
 476 enqueue_slot_back(const struct rte_hash *h,
 477                 struct lcore_cache *cached_free_slots,
 478                 void *slot_id)
 479 {
 480         if (h->hw_trans_mem_support) {
 481                 cached_free_slots->objs[cached_free_slots->len] = slot_id;
 482                 cached_free_slots->len++;
 483         } else
 484                 rte_ring_sp_enqueue(h->free_slots, slot_id);
 485 }
 486
 487 static inline int32_t
 488 __rte_hash_add_key_with_hash(const struct rte_hash *h, const void *key,
 489                                                 hash_sig_t sig, void *data)
 490 {
 491         hash_sig_t alt_hash;
 492         uint32_t prim_bucket_idx, sec_bucket_idx;
 493         unsigned i;
 494         struct rte_hash_bucket *prim_bkt, *sec_bkt;
 495         struct rte_hash_key *new_k, *k, *keys = h->key_store;
 496         void *slot_id = NULL;
 497         uint32_t new_idx;
 498         int ret;
 499         unsigned n_slots;
 500         unsigned lcore_id;
 501         struct lcore_cache *cached_free_slots = NULL;
 502         unsigned int nr_pushes = 0;
 503
 504         if (h->add_key == ADD_KEY_MULTIWRITER)
 505                 rte_spinlock_lock(h->multiwriter_lock);
 506
 507         prim_bucket_idx = sig & h->bucket_bitmask;
 508         prim_bkt = &h->buckets[prim_bucket_idx];
 509         rte_prefetch0(prim_bkt);
 510
 511         alt_hash = rte_hash_secondary_hash(sig);
 512         sec_bucket_idx = alt_hash & h->bucket_bitmask;
 513         sec_bkt = &h->buckets[sec_bucket_idx];
 514         rte_prefetch0(sec_bkt);
 515
 516         /* Get a new slot for storing the new key */
 517         if (h->hw_trans_mem_support) {
 518                 lcore_id = rte_lcore_id();
 519                 cached_free_slots = &h->local_free_slots[lcore_id];
 520                 /* Try to get a free slot from the local cache */
 521                 if (cached_free_slots->len == 0) {
 522                         /* Need to get another burst of free slots from global ring */
 523                         n_slots = rte_ring_mc_dequeue_burst(h->free_slots,
 524                                         cached_free_slots->objs,
 525                                         LCORE_CACHE_SIZE, NULL);
 526                         if (n_slots == 0) {
 527                                 ret = -ENOSPC;
 528                                 goto failure;
 529                         }
 530
 531                         cached_free_slots->len += n_slots;
 532                 }
 533
 534                 /* Get a free slot from the local cache */
 535                 cached_free_slots->len--;
 536                 slot_id = cached_free_slots->objs[cached_free_slots->len];
 537         } else {
 538                 if (rte_ring_sc_dequeue(h->free_slots, &slot_id) != 0) {
 539                         ret = -ENOSPC;
 540                         goto failure;
 541                 }
 542         }
 543
 544         new_k = RTE_PTR_ADD(keys, (uintptr_t)slot_id * h->key_entry_size);
 545         rte_prefetch0(new_k);
 546         new_idx = (uint32_t)((uintptr_t) slot_id);
 547
 548         /* Check if key is already inserted in primary location */
 549         for (i = 0; i < RTE_HASH_BUCKET_ENTRIES; i++) {
 550                 if (prim_bkt->sig_current[i] == sig &&
 551                                 prim_bkt->sig_alt[i] == alt_hash) {
 552                         k = (struct rte_hash_key *) ((char *)keys +
 553                                         prim_bkt->key_idx[i] * h->key_entry_size);
 554                         if (rte_hash_cmp_eq(key, k->key, h) == 0) {
 555                                 /* Enqueue index of free slot back in the ring. */
 556                                 enqueue_slot_back(h, cached_free_slots, slot_id);
 557                                 /* Update data */
 558                                 k->pdata = data;
 559                                 /*
 560                                  * Return index where key is stored,
 561                                  * subtracting the first dummy index
 562                                  */
 563                                 ret = prim_bkt->key_idx[i] - 1;
 564                                 goto failure;
 565                         }
 566                 }
 567         }
 568
 569         /* Check if key is already inserted in secondary location */
 570         for (i = 0; i < RTE_HASH_BUCKET_ENTRIES; i++) {
 571                 if (sec_bkt->sig_alt[i] == sig &&
 572                                 sec_bkt->sig_current[i] == alt_hash) {
 573                         k = (struct rte_hash_key *) ((char *)keys +
 574                                         sec_bkt->key_idx[i] * h->key_entry_size);
 575                         if (rte_hash_cmp_eq(key, k->key, h) == 0) {
 576                                 /* Enqueue index of free slot back in the ring. */
 577                                 enqueue_slot_back(h, cached_free_slots, slot_id);
 578                                 /* Update data */
 579                                 k->pdata = data;
 580                                 /*
 581                                  * Return index where key is stored,
 582                                  * subtracting the first dummy index
 583                                  */
 584                                 ret = sec_bkt->key_idx[i] - 1;
 585                                 goto failure;
 586                         }
 587                 }
 588         }
 589
 590         /* Copy key */
 591         rte_memcpy(new_k->key, key, h->key_len);
 592         new_k->pdata = data;
 593
 594 #if defined(RTE_ARCH_X86) /* currently only x86 support HTM */
 595         if (h->add_key == ADD_KEY_MULTIWRITER_TM) {
 596                 ret = rte_hash_cuckoo_insert_mw_tm(prim_bkt,
 597                                 sig, alt_hash, new_idx);
 598                 if (ret >= 0)
 599                         return new_idx - 1;
 600
 601                 /* Primary bucket full, need to make space for new entry */
 602                 ret = rte_hash_cuckoo_make_space_mw_tm(h, prim_bkt, sig,
 603                                                         alt_hash, new_idx);
 604
 605                 if (ret >= 0)
 606                         return new_idx - 1;
 607
 608                 /* Also search secondary bucket to get better occupancy */
 609                 ret = rte_hash_cuckoo_make_space_mw_tm(h, sec_bkt, sig,
 610                                                         alt_hash, new_idx);
 611
 612                 if (ret >= 0)
 613                         return new_idx - 1;
 614         } else {
 615 #endif
 616                 for (i = 0; i < RTE_HASH_BUCKET_ENTRIES; i++) {
 617                         /* Check if slot is available */
 618                         if (likely(prim_bkt->key_idx[i] == EMPTY_SLOT)) {
 619                                 prim_bkt->sig_current[i] = sig;
 620                                 prim_bkt->sig_alt[i] = alt_hash;
 621                                 prim_bkt->key_idx[i] = new_idx;
 622                                 break;
 623                         }
 624                 }
 625
 626                 if (i != RTE_HASH_BUCKET_ENTRIES) {
 627                         if (h->add_key == ADD_KEY_MULTIWRITER)
 628                                 rte_spinlock_unlock(h->multiwriter_lock);
 629                         return new_idx - 1;
 630                 }
 631
 632                 /* Primary bucket full, need to make space for new entry
 633                  * After recursive function.
 634                  * Insert the new entry in the position of the pushed entry
 635                  * if successful or return error and
 636                  * store the new slot back in the ring
 637                  */
 638                 ret = make_space_bucket(h, prim_bkt, &nr_pushes);
 639                 if (ret >= 0) {
 640                         prim_bkt->sig_current[ret] = sig;
 641                         prim_bkt->sig_alt[ret] = alt_hash;
 642                         prim_bkt->key_idx[ret] = new_idx;
 643                         if (h->add_key == ADD_KEY_MULTIWRITER)
 644                                 rte_spinlock_unlock(h->multiwriter_lock);
 645                         return new_idx - 1;
 646                 }
 647 #if defined(RTE_ARCH_X86)
 648         }
 649 #endif
 650         /* Error in addition, store new slot back in the ring and return error */
 651         enqueue_slot_back(h, cached_free_slots, (void *)((uintptr_t) new_idx));
 652
 653 failure:
 654         if (h->add_key == ADD_KEY_MULTIWRITER)
 655                 rte_spinlock_unlock(h->multiwriter_lock);
 656         return ret;
 657 }
 658
 659 int32_t
 660 rte_hash_add_key_with_hash(const struct rte_hash *h,
 661                         const void *key, hash_sig_t sig)
 662 {
 663         RETURN_IF_TRUE(((h == NULL) || (key == NULL)), -EINVAL);
 664         return __rte_hash_add_key_with_hash(h, key, sig, 0);
 665 }
 666
 667 int32_t
 668 rte_hash_add_key(const struct rte_hash *h, const void *key)
 669 {
 670         RETURN_IF_TRUE(((h == NULL) || (key == NULL)), -EINVAL);
 671         return __rte_hash_add_key_with_hash(h, key, rte_hash_hash(h, key), 0);
 672 }
 673
 674 int
 675 rte_hash_add_key_with_hash_data(const struct rte_hash *h,
 676                         const void *key, hash_sig_t sig, void *data)
 677 {
 678         int ret;
 679
 680         RETURN_IF_TRUE(((h == NULL) || (key == NULL)), -EINVAL);
 681         ret = __rte_hash_add_key_with_hash(h, key, sig, data);
 682         if (ret >= 0)
 683                 return 0;
 684         else
 685                 return ret;
 686 }
 687
 688 int
 689 rte_hash_add_key_data(const struct rte_hash *h, const void *key, void *data)
 690 {
 691         int ret;
 692
 693         RETURN_IF_TRUE(((h == NULL) || (key == NULL)), -EINVAL);
 694
 695         ret = __rte_hash_add_key_with_hash(h, key, rte_hash_hash(h, key), data);
 696         if (ret >= 0)
 697                 return 0;
 698         else
 699                 return ret;
 700 }
 701 static inline int32_t
 702 __rte_hash_lookup_with_hash(const struct rte_hash *h, const void *key,
 703                                         hash_sig_t sig, void **data)
 704 {
 705         uint32_t bucket_idx;
 706         hash_sig_t alt_hash;
 707         unsigned i;
 708         struct rte_hash_bucket *bkt;
 709         struct rte_hash_key *k, *keys = h->key_store;
 710
 711         bucket_idx = sig & h->bucket_bitmask;
 712         bkt = &h->buckets[bucket_idx];
 713
 714         /* Check if key is in primary location */
 715         for (i = 0; i < RTE_HASH_BUCKET_ENTRIES; i++) {
 716                 if (bkt->sig_current[i] == sig &&
 717                                 bkt->key_idx[i] != EMPTY_SLOT) {
 718                         k = (struct rte_hash_key *) ((char *)keys +
 719                                         bkt->key_idx[i] * h->key_entry_size);
 720                         if (rte_hash_cmp_eq(key, k->key, h) == 0) {
 721                                 if (data != NULL)
 722                                         *data = k->pdata;
 723                                 /*
 724                                  * Return index where key is stored,
 725                                  * subtracting the first dummy index
 726                                  */
 727                                 return bkt->key_idx[i] - 1;
 728                         }
 729                 }
 730         }
 731
 732         /* Calculate secondary hash */
 733         alt_hash = rte_hash_secondary_hash(sig);
 734         bucket_idx = alt_hash & h->bucket_bitmask;
 735         bkt = &h->buckets[bucket_idx];
 736
 737         /* Check if key is in secondary location */
 738         for (i = 0; i < RTE_HASH_BUCKET_ENTRIES; i++) {
 739                 if (bkt->sig_current[i] == alt_hash &&
 740                                 bkt->sig_alt[i] == sig) {
 741                         k = (struct rte_hash_key *) ((char *)keys +
 742                                         bkt->key_idx[i] * h->key_entry_size);
 743                         if (rte_hash_cmp_eq(key, k->key, h) == 0) {
 744                                 if (data != NULL)
 745                                         *data = k->pdata;
 746                                 /*
 747                                  * Return index where key is stored,
 748                                  * subtracting the first dummy index
 749                                  */
 750                                 return bkt->key_idx[i] - 1;
 751                         }
 752                 }
 753         }
 754
 755         return -ENOENT;
 756 }
 757
 758 int32_t
 759 rte_hash_lookup_with_hash(const struct rte_hash *h,
 760                         const void *key, hash_sig_t sig)
 761 {
 762         RETURN_IF_TRUE(((h == NULL) || (key == NULL)), -EINVAL);
 763         return __rte_hash_lookup_with_hash(h, key, sig, NULL);
 764 }
 765
 766 int32_t
 767 rte_hash_lookup(const struct rte_hash *h, const void *key)
 768 {
 769         RETURN_IF_TRUE(((h == NULL) || (key == NULL)), -EINVAL);
 770         return __rte_hash_lookup_with_hash(h, key, rte_hash_hash(h, key), NULL);
 771 }
 772
 773 int
 774 rte_hash_lookup_with_hash_data(const struct rte_hash *h,
 775                         const void *key, hash_sig_t sig, void **data)
 776 {
 777         RETURN_IF_TRUE(((h == NULL) || (key == NULL)), -EINVAL);
 778         return __rte_hash_lookup_with_hash(h, key, sig, data);
 779 }
 780
 781 int
 782 rte_hash_lookup_data(const struct rte_hash *h, const void *key, void **data)
 783 {
 784         RETURN_IF_TRUE(((h == NULL) || (key == NULL)), -EINVAL);
 785         return __rte_hash_lookup_with_hash(h, key, rte_hash_hash(h, key), data);
 786 }
 787
 788 static inline void
 789 remove_entry(const struct rte_hash *h, struct rte_hash_bucket *bkt, unsigned i)
 790 {
 791         unsigned lcore_id, n_slots;
 792         struct lcore_cache *cached_free_slots;
 793
 794         bkt->sig_current[i] = NULL_SIGNATURE;
 795         bkt->sig_alt[i] = NULL_SIGNATURE;
 796         if (h->hw_trans_mem_support) {
 797                 lcore_id = rte_lcore_id();
 798                 cached_free_slots = &h->local_free_slots[lcore_id];
 799                 /* Cache full, need to free it. */
 800                 if (cached_free_slots->len == LCORE_CACHE_SIZE) {
 801                         /* Need to enqueue the free slots in global ring. */
 802                         n_slots = rte_ring_mp_enqueue_burst(h->free_slots,
 803                                                 cached_free_slots->objs,
 804                                                 LCORE_CACHE_SIZE, NULL);
 805                         cached_free_slots->len -= n_slots;
 806                 }
 807                 /* Put index of new free slot in cache. */
 808                 cached_free_slots->objs[cached_free_slots->len] =
 809                                 (void *)((uintptr_t)bkt->key_idx[i]);
 810                 cached_free_slots->len++;
 811         } else {
 812                 rte_ring_sp_enqueue(h->free_slots,
 813                                 (void *)((uintptr_t)bkt->key_idx[i]));
 814         }
 815 }
 816
 817 static inline int32_t
 818 __rte_hash_del_key_with_hash(const struct rte_hash *h, const void *key,
 819                                                 hash_sig_t sig)
 820 {
 821         uint32_t bucket_idx;
 822         hash_sig_t alt_hash;
 823         unsigned i;
 824         struct rte_hash_bucket *bkt;
 825         struct rte_hash_key *k, *keys = h->key_store;
 826         int32_t ret;
 827
 828         bucket_idx = sig & h->bucket_bitmask;
 829         bkt = &h->buckets[bucket_idx];
 830
 831         /* Check if key is in primary location */
 832         for (i = 0; i < RTE_HASH_BUCKET_ENTRIES; i++) {
 833                 if (bkt->sig_current[i] == sig &&
 834                                 bkt->key_idx[i] != EMPTY_SLOT) {
 835                         k = (struct rte_hash_key *) ((char *)keys +
 836                                         bkt->key_idx[i] * h->key_entry_size);
 837                         if (rte_hash_cmp_eq(key, k->key, h) == 0) {
 838                                 remove_entry(h, bkt, i);
 839
 840                                 /*
 841                                  * Return index where key is stored,
 842                                  * subtracting the first dummy index
 843                                  */
 844                                 ret = bkt->key_idx[i] - 1;
 845                                 bkt->key_idx[i] = EMPTY_SLOT;
 846                                 return ret;
 847                         }
 848                 }
 849         }
 850
 851         /* Calculate secondary hash */
 852         alt_hash = rte_hash_secondary_hash(sig);
 853         bucket_idx = alt_hash & h->bucket_bitmask;
 854         bkt = &h->buckets[bucket_idx];
 855
 856         /* Check if key is in secondary location */
 857         for (i = 0; i < RTE_HASH_BUCKET_ENTRIES; i++) {
 858                 if (bkt->sig_current[i] == alt_hash &&
 859                                 bkt->key_idx[i] != EMPTY_SLOT) {
 860                         k = (struct rte_hash_key *) ((char *)keys +
 861                                         bkt->key_idx[i] * h->key_entry_size);
 862                         if (rte_hash_cmp_eq(key, k->key, h) == 0) {
 863                                 remove_entry(h, bkt, i);
 864
 865                                 /*
 866                                  * Return index where key is stored,
 867                                  * subtracting the first dummy index
 868                                  */
 869                                 ret = bkt->key_idx[i] - 1;
 870                                 bkt->key_idx[i] = EMPTY_SLOT;
 871                                 return ret;
 872                         }
 873                 }
 874         }
 875
 876         return -ENOENT;
 877 }
 878
 879 int32_t
 880 rte_hash_del_key_with_hash(const struct rte_hash *h,
 881                         const void *key, hash_sig_t sig)
 882 {
 883         RETURN_IF_TRUE(((h == NULL) || (key == NULL)), -EINVAL);
 884         return __rte_hash_del_key_with_hash(h, key, sig);
 885 }
 886
 887 int32_t
 888 rte_hash_del_key(const struct rte_hash *h, const void *key)
 889 {
 890         RETURN_IF_TRUE(((h == NULL) || (key == NULL)), -EINVAL);
 891         return __rte_hash_del_key_with_hash(h, key, rte_hash_hash(h, key));
 892 }
 893
 894 int
 895 rte_hash_get_key_with_position(const struct rte_hash *h, const int32_t position,
 896                                void **key)
 897 {
 898         RETURN_IF_TRUE(((h == NULL) || (key == NULL)), -EINVAL);
 899
 900         struct rte_hash_key *k, *keys = h->key_store;
 901         k = (struct rte_hash_key *) ((char *) keys + (position + 1) *
 902                                      h->key_entry_size);
 903         *key = k->key;
 904
 905         if (position !=
 906             __rte_hash_lookup_with_hash(h, *key, rte_hash_hash(h, *key),
 907                                         NULL)) {
 908                 return -ENOENT;
 909         }
 910
 911         return 0;
 912 }
 913
 914 static inline void
 915 compare_signatures(uint32_t *prim_hash_matches, uint32_t *sec_hash_matches,
 916                         const struct rte_hash_bucket *prim_bkt,
 917                         const struct rte_hash_bucket *sec_bkt,
 918                         hash_sig_t prim_hash, hash_sig_t sec_hash,
 919                         enum rte_hash_sig_compare_function sig_cmp_fn)
 920 {
 921         unsigned int i;
 922
 923         switch (sig_cmp_fn) {
 924 #ifdef RTE_MACHINE_CPUFLAG_AVX2
 925         case RTE_HASH_COMPARE_AVX2:
 926                 *prim_hash_matches = _mm256_movemask_ps((__m256)_mm256_cmpeq_epi32(
 927                                 _mm256_load_si256(
 928                                         (__m256i const *)prim_bkt->sig_current),
 929                                 _mm256_set1_epi32(prim_hash)));
 930                 *sec_hash_matches = _mm256_movemask_ps((__m256)_mm256_cmpeq_epi32(
 931                                 _mm256_load_si256(
 932                                         (__m256i const *)sec_bkt->sig_current),
 933                                 _mm256_set1_epi32(sec_hash)));
 934                 break;
 935 #endif
 936 #ifdef RTE_MACHINE_CPUFLAG_SSE2
 937         case RTE_HASH_COMPARE_SSE:
 938                 /* Compare the first 4 signatures in the bucket */
 939                 *prim_hash_matches = _mm_movemask_ps((__m128)_mm_cmpeq_epi16(
 940                                 _mm_load_si128(
 941                                         (__m128i const *)prim_bkt->sig_current),
 942                                 _mm_set1_epi32(prim_hash)));
 943                 *prim_hash_matches |= (_mm_movemask_ps((__m128)_mm_cmpeq_epi16(
 944                                 _mm_load_si128(
 945                                         (__m128i const *)&prim_bkt->sig_current[4]),
 946                                 _mm_set1_epi32(prim_hash)))) << 4;
 947                 /* Compare the first 4 signatures in the bucket */
 948                 *sec_hash_matches = _mm_movemask_ps((__m128)_mm_cmpeq_epi16(
 949                                 _mm_load_si128(
 950                                         (__m128i const *)sec_bkt->sig_current),
 951                                 _mm_set1_epi32(sec_hash)));
 952                 *sec_hash_matches |= (_mm_movemask_ps((__m128)_mm_cmpeq_epi16(
 953                                 _mm_load_si128(
 954                                         (__m128i const *)&sec_bkt->sig_current[4]),
 955                                 _mm_set1_epi32(sec_hash)))) << 4;
 956                 break;
 957 #endif
 958         default:
 959                 for (i = 0; i < RTE_HASH_BUCKET_ENTRIES; i++) {
 960                         *prim_hash_matches |=
 961                                 ((prim_hash == prim_bkt->sig_current[i]) << i);
 962                         *sec_hash_matches |=
 963                                 ((sec_hash == sec_bkt->sig_current[i]) << i);
 964                 }
 965         }
 966
 967 }
 968
 969 #define PREFETCH_OFFSET 4
 970 static inline void
 971 __rte_hash_lookup_bulk(const struct rte_hash *h, const void **keys,
 972                         int32_t num_keys, int32_t *positions,
 973                         uint64_t *hit_mask, void *data[])
 974 {
 975         uint64_t hits = 0;
 976         int32_t i;
 977         uint32_t prim_hash[RTE_HASH_LOOKUP_BULK_MAX];
 978         uint32_t sec_hash[RTE_HASH_LOOKUP_BULK_MAX];
 979         const struct rte_hash_bucket *primary_bkt[RTE_HASH_LOOKUP_BULK_MAX];
 980         const struct rte_hash_bucket *secondary_bkt[RTE_HASH_LOOKUP_BULK_MAX];
 981         uint32_t prim_hitmask[RTE_HASH_LOOKUP_BULK_MAX] = {0};
 982         uint32_t sec_hitmask[RTE_HASH_LOOKUP_BULK_MAX] = {0};
 983
 984         /* Prefetch first keys */
 985         for (i = 0; i < PREFETCH_OFFSET && i < num_keys; i++)
 986                 rte_prefetch0(keys[i]);
 987
 988         /*
 989          * Prefetch rest of the keys, calculate primary and
 990          * secondary bucket and prefetch them
 991          */
 992         for (i = 0; i < (num_keys - PREFETCH_OFFSET); i++) {
 993                 rte_prefetch0(keys[i + PREFETCH_OFFSET]);
 994
 995                 prim_hash[i] = rte_hash_hash(h, keys[i]);
 996                 sec_hash[i] = rte_hash_secondary_hash(prim_hash[i]);
 997
 998                 primary_bkt[i] = &h->buckets[prim_hash[i] & h->bucket_bitmask];
 999                 secondary_bkt[i] = &h->buckets[sec_hash[i] & h->bucket_bitmask];
1000
1001                 rte_prefetch0(primary_bkt[i]);
1002                 rte_prefetch0(secondary_bkt[i]);
1003         }
1004
1005         /* Calculate and prefetch rest of the buckets */
1006         for (; i < num_keys; i++) {
1007                 prim_hash[i] = rte_hash_hash(h, keys[i]);
1008                 sec_hash[i] = rte_hash_secondary_hash(prim_hash[i]);
1009
1010                 primary_bkt[i] = &h->buckets[prim_hash[i] & h->bucket_bitmask];
1011                 secondary_bkt[i] = &h->buckets[sec_hash[i] & h->bucket_bitmask];
1012
1013                 rte_prefetch0(primary_bkt[i]);
1014                 rte_prefetch0(secondary_bkt[i]);
1015         }
1016
1017         /* Compare signatures and prefetch key slot of first hit */
1018         for (i = 0; i < num_keys; i++) {
1019                 compare_signatures(&prim_hitmask[i], &sec_hitmask[i],
1020                                 primary_bkt[i], secondary_bkt[i],
1021                                 prim_hash[i], sec_hash[i], h->sig_cmp_fn);
1022
1023                 if (prim_hitmask[i]) {
1024                         uint32_t first_hit = __builtin_ctzl(prim_hitmask[i]);
1025                         uint32_t key_idx = primary_bkt[i]->key_idx[first_hit];
1026                         const struct rte_hash_key *key_slot =
1027                                 (const struct rte_hash_key *)(
1028                                 (const char *)h->key_store +
1029                                 key_idx * h->key_entry_size);
1030                         rte_prefetch0(key_slot);
1031                         continue;
1032                 }
1033
1034                 if (sec_hitmask[i]) {
1035                         uint32_t first_hit = __builtin_ctzl(sec_hitmask[i]);
1036                         uint32_t key_idx = secondary_bkt[i]->key_idx[first_hit];
1037                         const struct rte_hash_key *key_slot =
1038                                 (const struct rte_hash_key *)(
1039                                 (const char *)h->key_store +
1040                                 key_idx * h->key_entry_size);
1041                         rte_prefetch0(key_slot);
1042                 }
1043         }
1044
1045         /* Compare keys, first hits in primary first */
1046         for (i = 0; i < num_keys; i++) {
1047                 positions[i] = -ENOENT;
1048                 while (prim_hitmask[i]) {
1049                         uint32_t hit_index = __builtin_ctzl(prim_hitmask[i]);
1050
1051                         uint32_t key_idx = primary_bkt[i]->key_idx[hit_index];
1052                         const struct rte_hash_key *key_slot =
1053                                 (const struct rte_hash_key *)(
1054                                 (const char *)h->key_store +
1055                                 key_idx * h->key_entry_size);
1056                         /*
1057                          * If key index is 0, do not compare key,
1058                          * as it is checking the dummy slot
1059                          */
1060                         if (!!key_idx & !rte_hash_cmp_eq(key_slot->key, keys[i], h)) {
1061                                 if (data != NULL)
1062                                         data[i] = key_slot->pdata;
1063
1064                                 hits |= 1ULL << i;
1065                                 positions[i] = key_idx - 1;
1066                                 goto next_key;
1067                         }
1068                         prim_hitmask[i] &= ~(1 << (hit_index));
1069                 }
1070
1071                 while (sec_hitmask[i]) {
1072                         uint32_t hit_index = __builtin_ctzl(sec_hitmask[i]);
1073
1074                         uint32_t key_idx = secondary_bkt[i]->key_idx[hit_index];
1075                         const struct rte_hash_key *key_slot =
1076                                 (const struct rte_hash_key *)(
1077                                 (const char *)h->key_store +
1078                                 key_idx * h->key_entry_size);
1079                         /*
1080                          * If key index is 0, do not compare key,
1081                          * as it is checking the dummy slot
1082                          */
1083
1084                         if (!!key_idx & !rte_hash_cmp_eq(key_slot->key, keys[i], h)) {
1085                                 if (data != NULL)
1086                                         data[i] = key_slot->pdata;
1087
1088                                 hits |= 1ULL << i;
1089                                 positions[i] = key_idx - 1;
1090                                 goto next_key;
1091                         }
1092                         sec_hitmask[i] &= ~(1 << (hit_index));
1093                 }
1094
1095 next_key:
1096                 continue;
1097         }
1098
1099         if (hit_mask != NULL)
1100                 *hit_mask = hits;
1101 }
1102
1103 int
1104 rte_hash_lookup_bulk(const struct rte_hash *h, const void **keys,
1105                       uint32_t num_keys, int32_t *positions)
1106 {
1107         RETURN_IF_TRUE(((h == NULL) || (keys == NULL) || (num_keys == 0) ||
1108                         (num_keys > RTE_HASH_LOOKUP_BULK_MAX) ||
1109                         (positions == NULL)), -EINVAL);
1110
1111         __rte_hash_lookup_bulk(h, keys, num_keys, positions, NULL, NULL);
1112         return 0;
1113 }
1114
1115 int
1116 rte_hash_lookup_bulk_data(const struct rte_hash *h, const void **keys,
1117                       uint32_t num_keys, uint64_t *hit_mask, void *data[])
1118 {
1119         RETURN_IF_TRUE(((h == NULL) || (keys == NULL) || (num_keys == 0) ||
1120                         (num_keys > RTE_HASH_LOOKUP_BULK_MAX) ||
1121                         (hit_mask == NULL)), -EINVAL);
1122
1123         int32_t positions[num_keys];
1124
1125         __rte_hash_lookup_bulk(h, keys, num_keys, positions, hit_mask, data);
1126
1127         /* Return number of hits */
1128         return __builtin_popcountl(*hit_mask);
1129 }
1130
1131 int32_t
1132 rte_hash_iterate(const struct rte_hash *h, const void **key, void **data, uint32_t *next)
1133 {
1134         uint32_t bucket_idx, idx, position;
1135         struct rte_hash_key *next_key;
1136
1137         RETURN_IF_TRUE(((h == NULL) || (next == NULL)), -EINVAL);
1138
1139         const uint32_t total_entries = h->num_buckets * RTE_HASH_BUCKET_ENTRIES;
1140         /* Out of bounds */
1141         if (*next >= total_entries)
1142                 return -ENOENT;
1143
1144         /* Calculate bucket and index of current iterator */
1145         bucket_idx = *next / RTE_HASH_BUCKET_ENTRIES;
1146         idx = *next % RTE_HASH_BUCKET_ENTRIES;
1147
1148         /* If current position is empty, go to the next one */
1149         while (h->buckets[bucket_idx].key_idx[idx] == EMPTY_SLOT) {
1150                 (*next)++;
1151                 /* End of table */
1152                 if (*next == total_entries)
1153                         return -ENOENT;
1154                 bucket_idx = *next / RTE_HASH_BUCKET_ENTRIES;
1155                 idx = *next % RTE_HASH_BUCKET_ENTRIES;
1156         }
1157
1158         /* Get position of entry in key table */
1159         position = h->buckets[bucket_idx].key_idx[idx];
1160         next_key = (struct rte_hash_key *) ((char *)h->key_store +
1161                                 position * h->key_entry_size);
1162         /* Return key and data */
1163         *key = next_key->key;
1164         *data = next_key->pdata;
1165
1166         /* Increment iterator */
1167         (*next)++;
1168
1169         return position - 1;
1170 }