lib/librte_hash/rte_cuckoo_hash.c

   1 /*-
   2  *   BSD LICENSE
   3  *
   4  *   Copyright(c) 2010-2016 Intel Corporation. All rights reserved.
   5  *   All rights reserved.
   6  *
   7  *   Redistribution and use in source and binary forms, with or without
   8  *   modification, are permitted provided that the following conditions
   9  *   are met:
  10  *
  11  *     * Redistributions of source code must retain the above copyright
  12  *       notice, this list of conditions and the following disclaimer.
  13  *     * Redistributions in binary form must reproduce the above copyright
  14  *       notice, this list of conditions and the following disclaimer in
  15  *       the documentation and/or other materials provided with the
  16  *       distribution.
  17  *     * Neither the name of Intel Corporation nor the names of its
  18  *       contributors may be used to endorse or promote products derived
  19  *       from this software without specific prior written permission.
  20  *
  21  *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  22  *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  23  *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  24  *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  25  *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  26  *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  27  *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  28  *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  29  *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  30  *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  31  *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  32  */
  33
  34 #include <string.h>
  35 #include <stdint.h>
  36 #include <errno.h>
  37 #include <stdio.h>
  38 #include <stdarg.h>
  39 #include <sys/queue.h>
  40
  41 #include <rte_common.h>
  42 #include <rte_memory.h>         /* for definition of RTE_CACHE_LINE_SIZE */
  43 #include <rte_log.h>
  44 #include <rte_memcpy.h>
  45 #include <rte_prefetch.h>
  46 #include <rte_branch_prediction.h>
  47 #include <rte_memzone.h>
  48 #include <rte_malloc.h>
  49 #include <rte_eal.h>
  50 #include <rte_eal_memconfig.h>
  51 #include <rte_per_lcore.h>
  52 #include <rte_errno.h>
  53 #include <rte_string_fns.h>
  54 #include <rte_cpuflags.h>
  55 #include <rte_log.h>
  56 #include <rte_rwlock.h>
  57 #include <rte_spinlock.h>
  58 #include <rte_ring.h>
  59 #include <rte_compat.h>
  60
  61 #include "rte_hash.h"
  62 #include "rte_cuckoo_hash.h"
  63
  64 #if defined(RTE_ARCH_X86)
  65 #include "rte_cuckoo_hash_x86.h"
  66 #endif
  67
  68 TAILQ_HEAD(rte_hash_list, rte_tailq_entry);
  69
  70 static struct rte_tailq_elem rte_hash_tailq = {
  71         .name = "RTE_HASH",
  72 };
  73 EAL_REGISTER_TAILQ(rte_hash_tailq)
  74
  75 struct rte_hash *
  76 rte_hash_find_existing(const char *name)
  77 {
  78         struct rte_hash *h = NULL;
  79         struct rte_tailq_entry *te;
  80         struct rte_hash_list *hash_list;
  81
  82         hash_list = RTE_TAILQ_CAST(rte_hash_tailq.head, rte_hash_list);
  83
  84         rte_rwlock_read_lock(RTE_EAL_TAILQ_RWLOCK);
  85         TAILQ_FOREACH(te, hash_list, next) {
  86                 h = (struct rte_hash *) te->data;
  87                 if (strncmp(name, h->name, RTE_HASH_NAMESIZE) == 0)
  88                         break;
  89         }
  90         rte_rwlock_read_unlock(RTE_EAL_TAILQ_RWLOCK);
  91
  92         if (te == NULL) {
  93                 rte_errno = ENOENT;
  94                 return NULL;
  95         }
  96         return h;
  97 }
  98
  99 void rte_hash_set_cmp_func(struct rte_hash *h, rte_hash_cmp_eq_t func)
 100 {
 101         h->cmp_jump_table_idx = KEY_CUSTOM;
 102         h->rte_hash_custom_cmp_eq = func;
 103 }
 104
 105 static inline int
 106 rte_hash_cmp_eq(const void *key1, const void *key2, const struct rte_hash *h)
 107 {
 108         if (h->cmp_jump_table_idx == KEY_CUSTOM)
 109                 return h->rte_hash_custom_cmp_eq(key1, key2, h->key_len);
 110         else
 111                 return cmp_jump_table[h->cmp_jump_table_idx](key1, key2, h->key_len);
 112 }
 113
 114 struct rte_hash *
 115 rte_hash_create(const struct rte_hash_parameters *params)
 116 {
 117         struct rte_hash *h = NULL;
 118         struct rte_tailq_entry *te = NULL;
 119         struct rte_hash_list *hash_list;
 120         struct rte_ring *r = NULL;
 121         char hash_name[RTE_HASH_NAMESIZE];
 122         void *k = NULL;
 123         void *buckets = NULL;
 124         char ring_name[RTE_RING_NAMESIZE];
 125         unsigned num_key_slots;
 126         unsigned hw_trans_mem_support = 0;
 127         unsigned i;
 128
 129         hash_list = RTE_TAILQ_CAST(rte_hash_tailq.head, rte_hash_list);
 130
 131         if (params == NULL) {
 132                 RTE_LOG(ERR, HASH, "rte_hash_create has no parameters\n");
 133                 return NULL;
 134         }
 135
 136         /* Check for valid parameters */
 137         if ((params->entries > RTE_HASH_ENTRIES_MAX) ||
 138                         (params->entries < RTE_HASH_BUCKET_ENTRIES) ||
 139                         !rte_is_power_of_2(RTE_HASH_BUCKET_ENTRIES) ||
 140                         (params->key_len == 0)) {
 141                 rte_errno = EINVAL;
 142                 RTE_LOG(ERR, HASH, "rte_hash_create has invalid parameters\n");
 143                 return NULL;
 144         }
 145
 146         /* Check extra flags field to check extra options. */
 147         if (params->extra_flag & RTE_HASH_EXTRA_FLAGS_TRANS_MEM_SUPPORT)
 148                 hw_trans_mem_support = 1;
 149
 150         /* Store all keys and leave the first entry as a dummy entry for lookup_bulk */
 151         if (hw_trans_mem_support)
 152                 /*
 153                  * Increase number of slots by total number of indices
 154                  * that can be stored in the lcore caches
 155                  * except for the first cache
 156                  */
 157                 num_key_slots = params->entries + (RTE_MAX_LCORE - 1) *
 158                                         LCORE_CACHE_SIZE + 1;
 159         else
 160                 num_key_slots = params->entries + 1;
 161
 162         snprintf(ring_name, sizeof(ring_name), "HT_%s", params->name);
 163         /* Create ring (Dummy slot index is not enqueued) */
 164         r = rte_ring_create(ring_name, rte_align32pow2(num_key_slots - 1),
 165                         params->socket_id, 0);
 166         if (r == NULL) {
 167                 RTE_LOG(ERR, HASH, "memory allocation failed\n");
 168                 goto err;
 169         }
 170
 171         snprintf(hash_name, sizeof(hash_name), "HT_%s", params->name);
 172
 173         rte_rwlock_write_lock(RTE_EAL_TAILQ_RWLOCK);
 174
 175         /* guarantee there's no existing: this is normally already checked
 176          * by ring creation above */
 177         TAILQ_FOREACH(te, hash_list, next) {
 178                 h = (struct rte_hash *) te->data;
 179                 if (strncmp(params->name, h->name, RTE_HASH_NAMESIZE) == 0)
 180                         break;
 181         }
 182         h = NULL;
 183         if (te != NULL) {
 184                 rte_errno = EEXIST;
 185                 te = NULL;
 186                 goto err_unlock;
 187         }
 188
 189         te = rte_zmalloc("HASH_TAILQ_ENTRY", sizeof(*te), 0);
 190         if (te == NULL) {
 191                 RTE_LOG(ERR, HASH, "tailq entry allocation failed\n");
 192                 goto err_unlock;
 193         }
 194
 195         h = (struct rte_hash *)rte_zmalloc_socket(hash_name, sizeof(struct rte_hash),
 196                                         RTE_CACHE_LINE_SIZE, params->socket_id);
 197
 198         if (h == NULL) {
 199                 RTE_LOG(ERR, HASH, "memory allocation failed\n");
 200                 goto err_unlock;
 201         }
 202
 203         const uint32_t num_buckets = rte_align32pow2(params->entries)
 204                                         / RTE_HASH_BUCKET_ENTRIES;
 205
 206         buckets = rte_zmalloc_socket(NULL,
 207                                 num_buckets * sizeof(struct rte_hash_bucket),
 208                                 RTE_CACHE_LINE_SIZE, params->socket_id);
 209
 210         if (buckets == NULL) {
 211                 RTE_LOG(ERR, HASH, "memory allocation failed\n");
 212                 goto err_unlock;
 213         }
 214
 215         const uint32_t key_entry_size = sizeof(struct rte_hash_key) + params->key_len;
 216         const uint64_t key_tbl_size = (uint64_t) key_entry_size * num_key_slots;
 217
 218         k = rte_zmalloc_socket(NULL, key_tbl_size,
 219                         RTE_CACHE_LINE_SIZE, params->socket_id);
 220
 221         if (k == NULL) {
 222                 RTE_LOG(ERR, HASH, "memory allocation failed\n");
 223                 goto err_unlock;
 224         }
 225
 226 /*
 227  * If x86 architecture is used, select appropriate compare function,
 228  * which may use x86 intrinsics, otherwise use memcmp
 229  */
 230 #if defined(RTE_ARCH_X86) || defined(RTE_ARCH_ARM64)
 231         /* Select function to compare keys */
 232         switch (params->key_len) {
 233         case 16:
 234                 h->cmp_jump_table_idx = KEY_16_BYTES;
 235                 break;
 236         case 32:
 237                 h->cmp_jump_table_idx = KEY_32_BYTES;
 238                 break;
 239         case 48:
 240                 h->cmp_jump_table_idx = KEY_48_BYTES;
 241                 break;
 242         case 64:
 243                 h->cmp_jump_table_idx = KEY_64_BYTES;
 244                 break;
 245         case 80:
 246                 h->cmp_jump_table_idx = KEY_80_BYTES;
 247                 break;
 248         case 96:
 249                 h->cmp_jump_table_idx = KEY_96_BYTES;
 250                 break;
 251         case 112:
 252                 h->cmp_jump_table_idx = KEY_112_BYTES;
 253                 break;
 254         case 128:
 255                 h->cmp_jump_table_idx = KEY_128_BYTES;
 256                 break;
 257         default:
 258                 /* If key is not multiple of 16, use generic memcmp */
 259                 h->cmp_jump_table_idx = KEY_OTHER_BYTES;
 260         }
 261 #else
 262         h->cmp_jump_table_idx = KEY_OTHER_BYTES;
 263 #endif
 264
 265         if (hw_trans_mem_support) {
 266                 h->local_free_slots = rte_zmalloc_socket(NULL,
 267                                 sizeof(struct lcore_cache) * RTE_MAX_LCORE,
 268                                 RTE_CACHE_LINE_SIZE, params->socket_id);
 269         }
 270
 271         /* Setup hash context */
 272         snprintf(h->name, sizeof(h->name), "%s", params->name);
 273         h->entries = params->entries;
 274         h->key_len = params->key_len;
 275         h->key_entry_size = key_entry_size;
 276         h->hash_func_init_val = params->hash_func_init_val;
 277
 278         h->num_buckets = num_buckets;
 279         h->bucket_bitmask = h->num_buckets - 1;
 280         h->buckets = buckets;
 281         h->hash_func = (params->hash_func == NULL) ?
 282                 DEFAULT_HASH_FUNC : params->hash_func;
 283         h->key_store = k;
 284         h->free_slots = r;
 285         h->hw_trans_mem_support = hw_trans_mem_support;
 286
 287 #if defined(RTE_ARCH_X86)
 288         if (rte_cpu_get_flag_enabled(RTE_CPUFLAG_AVX2))
 289                 h->sig_cmp_fn = RTE_HASH_COMPARE_AVX2;
 290         else if (rte_cpu_get_flag_enabled(RTE_CPUFLAG_SSE2))
 291                 h->sig_cmp_fn = RTE_HASH_COMPARE_SSE;
 292         else
 293 #endif
 294                 h->sig_cmp_fn = RTE_HASH_COMPARE_SCALAR;
 295
 296         /* Turn on multi-writer only with explicit flat from user and TM
 297          * support.
 298          */
 299         if (params->extra_flag & RTE_HASH_EXTRA_FLAGS_MULTI_WRITER_ADD) {
 300                 if (h->hw_trans_mem_support) {
 301                         h->add_key = ADD_KEY_MULTIWRITER_TM;
 302                 } else {
 303                         h->add_key = ADD_KEY_MULTIWRITER;
 304                         h->multiwriter_lock = rte_malloc(NULL,
 305                                                         sizeof(rte_spinlock_t),
 306                                                         LCORE_CACHE_SIZE);
 307                         rte_spinlock_init(h->multiwriter_lock);
 308                 }
 309         } else
 310                 h->add_key = ADD_KEY_SINGLEWRITER;
 311
 312         /* Populate free slots ring. Entry zero is reserved for key misses. */
 313         for (i = 1; i < params->entries + 1; i++)
 314                 rte_ring_sp_enqueue(r, (void *)((uintptr_t) i));
 315
 316         te->data = (void *) h;
 317         TAILQ_INSERT_TAIL(hash_list, te, next);
 318         rte_rwlock_write_unlock(RTE_EAL_TAILQ_RWLOCK);
 319
 320         return h;
 321 err_unlock:
 322         rte_rwlock_write_unlock(RTE_EAL_TAILQ_RWLOCK);
 323 err:
 324         rte_ring_free(r);
 325         rte_free(te);
 326         rte_free(h);
 327         rte_free(buckets);
 328         rte_free(k);
 329         return NULL;
 330 }
 331
 332 void
 333 rte_hash_free(struct rte_hash *h)
 334 {
 335         struct rte_tailq_entry *te;
 336         struct rte_hash_list *hash_list;
 337
 338         if (h == NULL)
 339                 return;
 340
 341         hash_list = RTE_TAILQ_CAST(rte_hash_tailq.head, rte_hash_list);
 342
 343         rte_rwlock_write_lock(RTE_EAL_TAILQ_RWLOCK);
 344
 345         /* find out tailq entry */
 346         TAILQ_FOREACH(te, hash_list, next) {
 347                 if (te->data == (void *) h)
 348                         break;
 349         }
 350
 351         if (te == NULL) {
 352                 rte_rwlock_write_unlock(RTE_EAL_TAILQ_RWLOCK);
 353                 return;
 354         }
 355
 356         TAILQ_REMOVE(hash_list, te, next);
 357
 358         rte_rwlock_write_unlock(RTE_EAL_TAILQ_RWLOCK);
 359
 360         if (h->hw_trans_mem_support)
 361                 rte_free(h->local_free_slots);
 362
 363         if (h->add_key == ADD_KEY_MULTIWRITER)
 364                 rte_free(h->multiwriter_lock);
 365         rte_ring_free(h->free_slots);
 366         rte_free(h->key_store);
 367         rte_free(h->buckets);
 368         rte_free(h);
 369         rte_free(te);
 370 }
 371
 372 hash_sig_t
 373 rte_hash_hash(const struct rte_hash *h, const void *key)
 374 {
 375         /* calc hash result by key */
 376         return h->hash_func(key, h->key_len, h->hash_func_init_val);
 377 }
 378
 379 /* Calc the secondary hash value from the primary hash value of a given key */
 380 static inline hash_sig_t
 381 rte_hash_secondary_hash(const hash_sig_t primary_hash)
 382 {
 383         static const unsigned all_bits_shift = 12;
 384         static const unsigned alt_bits_xor = 0x5bd1e995;
 385
 386         uint32_t tag = primary_hash >> all_bits_shift;
 387
 388         return primary_hash ^ ((tag + 1) * alt_bits_xor);
 389 }
 390
 391 void
 392 rte_hash_reset(struct rte_hash *h)
 393 {
 394         void *ptr;
 395         unsigned i;
 396
 397         if (h == NULL)
 398                 return;
 399
 400         memset(h->buckets, 0, h->num_buckets * sizeof(struct rte_hash_bucket));
 401         memset(h->key_store, 0, h->key_entry_size * (h->entries + 1));
 402
 403         /* clear the free ring */
 404         while (rte_ring_dequeue(h->free_slots, &ptr) == 0)
 405                 rte_pause();
 406
 407         /* Repopulate the free slots ring. Entry zero is reserved for key misses */
 408         for (i = 1; i < h->entries + 1; i++)
 409                 rte_ring_sp_enqueue(h->free_slots, (void *)((uintptr_t) i));
 410
 411         if (h->hw_trans_mem_support) {
 412                 /* Reset local caches per lcore */
 413                 for (i = 0; i < RTE_MAX_LCORE; i++)
 414                         h->local_free_slots[i].len = 0;
 415         }
 416 }
 417
 418 /* Search for an entry that can be pushed to its alternative location */
 419 static inline int
 420 make_space_bucket(const struct rte_hash *h, struct rte_hash_bucket *bkt,
 421                 unsigned int *nr_pushes)
 422 {
 423         unsigned i, j;
 424         int ret;
 425         uint32_t next_bucket_idx;
 426         struct rte_hash_bucket *next_bkt[RTE_HASH_BUCKET_ENTRIES];
 427
 428         /*
 429          * Push existing item (search for bucket with space in
 430          * alternative locations) to its alternative location
 431          */
 432         for (i = 0; i < RTE_HASH_BUCKET_ENTRIES; i++) {
 433                 /* Search for space in alternative locations */
 434                 next_bucket_idx = bkt->sig_alt[i] & h->bucket_bitmask;
 435                 next_bkt[i] = &h->buckets[next_bucket_idx];
 436                 for (j = 0; j < RTE_HASH_BUCKET_ENTRIES; j++) {
 437                         if (next_bkt[i]->key_idx[j] == EMPTY_SLOT)
 438                                 break;
 439                 }
 440
 441                 if (j != RTE_HASH_BUCKET_ENTRIES)
 442                         break;
 443         }
 444
 445         /* Alternative location has spare room (end of recursive function) */
 446         if (i != RTE_HASH_BUCKET_ENTRIES) {
 447                 next_bkt[i]->sig_alt[j] = bkt->sig_current[i];
 448                 next_bkt[i]->sig_current[j] = bkt->sig_alt[i];
 449                 next_bkt[i]->key_idx[j] = bkt->key_idx[i];
 450                 return i;
 451         }
 452
 453         /* Pick entry that has not been pushed yet */
 454         for (i = 0; i < RTE_HASH_BUCKET_ENTRIES; i++)
 455                 if (bkt->flag[i] == 0)
 456                         break;
 457
 458         /* All entries have been pushed, so entry cannot be added */
 459         if (i == RTE_HASH_BUCKET_ENTRIES || ++(*nr_pushes) > RTE_HASH_MAX_PUSHES)
 460                 return -ENOSPC;
 461
 462         /* Set flag to indicate that this entry is going to be pushed */
 463         bkt->flag[i] = 1;
 464
 465         /* Need room in alternative bucket to insert the pushed entry */
 466         ret = make_space_bucket(h, next_bkt[i], nr_pushes);
 467         /*
 468          * After recursive function.
 469          * Clear flags and insert the pushed entry
 470          * in its alternative location if successful,
 471          * or return error
 472          */
 473         bkt->flag[i] = 0;
 474         if (ret >= 0) {
 475                 next_bkt[i]->sig_alt[ret] = bkt->sig_current[i];
 476                 next_bkt[i]->sig_current[ret] = bkt->sig_alt[i];
 477                 next_bkt[i]->key_idx[ret] = bkt->key_idx[i];
 478                 return i;
 479         } else
 480                 return ret;
 481
 482 }
 483
 484 /*
 485  * Function called to enqueue back an index in the cache/ring,
 486  * as slot has not being used and it can be used in the
 487  * next addition attempt.
 488  */
 489 static inline void
 490 enqueue_slot_back(const struct rte_hash *h,
 491                 struct lcore_cache *cached_free_slots,
 492                 void *slot_id)
 493 {
 494         if (h->hw_trans_mem_support) {
 495                 cached_free_slots->objs[cached_free_slots->len] = slot_id;
 496                 cached_free_slots->len++;
 497         } else
 498                 rte_ring_sp_enqueue(h->free_slots, slot_id);
 499 }
 500
 501 static inline int32_t
 502 __rte_hash_add_key_with_hash(const struct rte_hash *h, const void *key,
 503                                                 hash_sig_t sig, void *data)
 504 {
 505         hash_sig_t alt_hash;
 506         uint32_t prim_bucket_idx, sec_bucket_idx;
 507         unsigned i;
 508         struct rte_hash_bucket *prim_bkt, *sec_bkt;
 509         struct rte_hash_key *new_k, *k, *keys = h->key_store;
 510         void *slot_id = NULL;
 511         uint32_t new_idx;
 512         int ret;
 513         unsigned n_slots;
 514         unsigned lcore_id;
 515         struct lcore_cache *cached_free_slots = NULL;
 516         unsigned int nr_pushes = 0;
 517
 518         if (h->add_key == ADD_KEY_MULTIWRITER)
 519                 rte_spinlock_lock(h->multiwriter_lock);
 520
 521         prim_bucket_idx = sig & h->bucket_bitmask;
 522         prim_bkt = &h->buckets[prim_bucket_idx];
 523         rte_prefetch0(prim_bkt);
 524
 525         alt_hash = rte_hash_secondary_hash(sig);
 526         sec_bucket_idx = alt_hash & h->bucket_bitmask;
 527         sec_bkt = &h->buckets[sec_bucket_idx];
 528         rte_prefetch0(sec_bkt);
 529
 530         /* Get a new slot for storing the new key */
 531         if (h->hw_trans_mem_support) {
 532                 lcore_id = rte_lcore_id();
 533                 cached_free_slots = &h->local_free_slots[lcore_id];
 534                 /* Try to get a free slot from the local cache */
 535                 if (cached_free_slots->len == 0) {
 536                         /* Need to get another burst of free slots from global ring */
 537                         n_slots = rte_ring_mc_dequeue_burst(h->free_slots,
 538                                         cached_free_slots->objs, LCORE_CACHE_SIZE);
 539                         if (n_slots == 0)
 540                                 return -ENOSPC;
 541
 542                         cached_free_slots->len += n_slots;
 543                 }
 544
 545                 /* Get a free slot from the local cache */
 546                 cached_free_slots->len--;
 547                 slot_id = cached_free_slots->objs[cached_free_slots->len];
 548         } else {
 549                 if (rte_ring_sc_dequeue(h->free_slots, &slot_id) != 0)
 550                         return -ENOSPC;
 551         }
 552
 553         new_k = RTE_PTR_ADD(keys, (uintptr_t)slot_id * h->key_entry_size);
 554         rte_prefetch0(new_k);
 555         new_idx = (uint32_t)((uintptr_t) slot_id);
 556
 557         /* Check if key is already inserted in primary location */
 558         for (i = 0; i < RTE_HASH_BUCKET_ENTRIES; i++) {
 559                 if (prim_bkt->sig_current[i] == sig &&
 560                                 prim_bkt->sig_alt[i] == alt_hash) {
 561                         k = (struct rte_hash_key *) ((char *)keys +
 562                                         prim_bkt->key_idx[i] * h->key_entry_size);
 563                         if (rte_hash_cmp_eq(key, k->key, h) == 0) {
 564                                 /* Enqueue index of free slot back in the ring. */
 565                                 enqueue_slot_back(h, cached_free_slots, slot_id);
 566                                 /* Update data */
 567                                 k->pdata = data;
 568                                 /*
 569                                  * Return index where key is stored,
 570                                  * substracting the first dummy index
 571                                  */
 572                                 return prim_bkt->key_idx[i] - 1;
 573                         }
 574                 }
 575         }
 576
 577         /* Check if key is already inserted in secondary location */
 578         for (i = 0; i < RTE_HASH_BUCKET_ENTRIES; i++) {
 579                 if (sec_bkt->sig_alt[i] == sig &&
 580                                 sec_bkt->sig_current[i] == alt_hash) {
 581                         k = (struct rte_hash_key *) ((char *)keys +
 582                                         sec_bkt->key_idx[i] * h->key_entry_size);
 583                         if (rte_hash_cmp_eq(key, k->key, h) == 0) {
 584                                 /* Enqueue index of free slot back in the ring. */
 585                                 enqueue_slot_back(h, cached_free_slots, slot_id);
 586                                 /* Update data */
 587                                 k->pdata = data;
 588                                 /*
 589                                  * Return index where key is stored,
 590                                  * substracting the first dummy index
 591                                  */
 592                                 return sec_bkt->key_idx[i] - 1;
 593                         }
 594                 }
 595         }
 596
 597         /* Copy key */
 598         rte_memcpy(new_k->key, key, h->key_len);
 599         new_k->pdata = data;
 600
 601 #if defined(RTE_ARCH_X86) /* currently only x86 support HTM */
 602         if (h->add_key == ADD_KEY_MULTIWRITER_TM) {
 603                 ret = rte_hash_cuckoo_insert_mw_tm(prim_bkt,
 604                                 sig, alt_hash, new_idx);
 605                 if (ret >= 0)
 606                         return new_idx - 1;
 607
 608                 /* Primary bucket full, need to make space for new entry */
 609                 ret = rte_hash_cuckoo_make_space_mw_tm(h, prim_bkt, sig,
 610                                                         alt_hash, new_idx);
 611
 612                 if (ret >= 0)
 613                         return new_idx - 1;
 614
 615                 /* Also search secondary bucket to get better occupancy */
 616                 ret = rte_hash_cuckoo_make_space_mw_tm(h, sec_bkt, sig,
 617                                                         alt_hash, new_idx);
 618
 619                 if (ret >= 0)
 620                         return new_idx - 1;
 621         } else {
 622 #endif
 623                 for (i = 0; i < RTE_HASH_BUCKET_ENTRIES; i++) {
 624                         /* Check if slot is available */
 625                         if (likely(prim_bkt->key_idx[i] == EMPTY_SLOT)) {
 626                                 prim_bkt->sig_current[i] = sig;
 627                                 prim_bkt->sig_alt[i] = alt_hash;
 628                                 prim_bkt->key_idx[i] = new_idx;
 629                                 break;
 630                         }
 631                 }
 632
 633                 if (i != RTE_HASH_BUCKET_ENTRIES) {
 634                         if (h->add_key == ADD_KEY_MULTIWRITER)
 635                                 rte_spinlock_unlock(h->multiwriter_lock);
 636                         return new_idx - 1;
 637                 }
 638
 639                 /* Primary bucket full, need to make space for new entry
 640                  * After recursive function.
 641                  * Insert the new entry in the position of the pushed entry
 642                  * if successful or return error and
 643                  * store the new slot back in the ring
 644                  */
 645                 ret = make_space_bucket(h, prim_bkt, &nr_pushes);
 646                 if (ret >= 0) {
 647                         prim_bkt->sig_current[ret] = sig;
 648                         prim_bkt->sig_alt[ret] = alt_hash;
 649                         prim_bkt->key_idx[ret] = new_idx;
 650                         if (h->add_key == ADD_KEY_MULTIWRITER)
 651                                 rte_spinlock_unlock(h->multiwriter_lock);
 652                         return new_idx - 1;
 653                 }
 654 #if defined(RTE_ARCH_X86)
 655         }
 656 #endif
 657         /* Error in addition, store new slot back in the ring and return error */
 658         enqueue_slot_back(h, cached_free_slots, (void *)((uintptr_t) new_idx));
 659
 660         if (h->add_key == ADD_KEY_MULTIWRITER)
 661                 rte_spinlock_unlock(h->multiwriter_lock);
 662         return ret;
 663 }
 664
 665 int32_t
 666 rte_hash_add_key_with_hash(const struct rte_hash *h,
 667                         const void *key, hash_sig_t sig)
 668 {
 669         RETURN_IF_TRUE(((h == NULL) || (key == NULL)), -EINVAL);
 670         return __rte_hash_add_key_with_hash(h, key, sig, 0);
 671 }
 672
 673 int32_t
 674 rte_hash_add_key(const struct rte_hash *h, const void *key)
 675 {
 676         RETURN_IF_TRUE(((h == NULL) || (key == NULL)), -EINVAL);
 677         return __rte_hash_add_key_with_hash(h, key, rte_hash_hash(h, key), 0);
 678 }
 679
 680 int
 681 rte_hash_add_key_with_hash_data(const struct rte_hash *h,
 682                         const void *key, hash_sig_t sig, void *data)
 683 {
 684         int ret;
 685
 686         RETURN_IF_TRUE(((h == NULL) || (key == NULL)), -EINVAL);
 687         ret = __rte_hash_add_key_with_hash(h, key, sig, data);
 688         if (ret >= 0)
 689                 return 0;
 690         else
 691                 return ret;
 692 }
 693
 694 int
 695 rte_hash_add_key_data(const struct rte_hash *h, const void *key, void *data)
 696 {
 697         int ret;
 698
 699         RETURN_IF_TRUE(((h == NULL) || (key == NULL)), -EINVAL);
 700
 701         ret = __rte_hash_add_key_with_hash(h, key, rte_hash_hash(h, key), data);
 702         if (ret >= 0)
 703                 return 0;
 704         else
 705                 return ret;
 706 }
 707 static inline int32_t
 708 __rte_hash_lookup_with_hash(const struct rte_hash *h, const void *key,
 709                                         hash_sig_t sig, void **data)
 710 {
 711         uint32_t bucket_idx;
 712         hash_sig_t alt_hash;
 713         unsigned i;
 714         struct rte_hash_bucket *bkt;
 715         struct rte_hash_key *k, *keys = h->key_store;
 716
 717         bucket_idx = sig & h->bucket_bitmask;
 718         bkt = &h->buckets[bucket_idx];
 719
 720         /* Check if key is in primary location */
 721         for (i = 0; i < RTE_HASH_BUCKET_ENTRIES; i++) {
 722                 if (bkt->sig_current[i] == sig &&
 723                                 bkt->key_idx[i] != EMPTY_SLOT) {
 724                         k = (struct rte_hash_key *) ((char *)keys +
 725                                         bkt->key_idx[i] * h->key_entry_size);
 726                         if (rte_hash_cmp_eq(key, k->key, h) == 0) {
 727                                 if (data != NULL)
 728                                         *data = k->pdata;
 729                                 /*
 730                                  * Return index where key is stored,
 731                                  * substracting the first dummy index
 732                                  */
 733                                 return bkt->key_idx[i] - 1;
 734                         }
 735                 }
 736         }
 737
 738         /* Calculate secondary hash */
 739         alt_hash = rte_hash_secondary_hash(sig);
 740         bucket_idx = alt_hash & h->bucket_bitmask;
 741         bkt = &h->buckets[bucket_idx];
 742
 743         /* Check if key is in secondary location */
 744         for (i = 0; i < RTE_HASH_BUCKET_ENTRIES; i++) {
 745                 if (bkt->sig_current[i] == alt_hash &&
 746                                 bkt->sig_alt[i] == sig) {
 747                         k = (struct rte_hash_key *) ((char *)keys +
 748                                         bkt->key_idx[i] * h->key_entry_size);
 749                         if (rte_hash_cmp_eq(key, k->key, h) == 0) {
 750                                 if (data != NULL)
 751                                         *data = k->pdata;
 752                                 /*
 753                                  * Return index where key is stored,
 754                                  * substracting the first dummy index
 755                                  */
 756                                 return bkt->key_idx[i] - 1;
 757                         }
 758                 }
 759         }
 760
 761         return -ENOENT;
 762 }
 763
 764 int32_t
 765 rte_hash_lookup_with_hash(const struct rte_hash *h,
 766                         const void *key, hash_sig_t sig)
 767 {
 768         RETURN_IF_TRUE(((h == NULL) || (key == NULL)), -EINVAL);
 769         return __rte_hash_lookup_with_hash(h, key, sig, NULL);
 770 }
 771
 772 int32_t
 773 rte_hash_lookup(const struct rte_hash *h, const void *key)
 774 {
 775         RETURN_IF_TRUE(((h == NULL) || (key == NULL)), -EINVAL);
 776         return __rte_hash_lookup_with_hash(h, key, rte_hash_hash(h, key), NULL);
 777 }
 778
 779 int
 780 rte_hash_lookup_with_hash_data(const struct rte_hash *h,
 781                         const void *key, hash_sig_t sig, void **data)
 782 {
 783         RETURN_IF_TRUE(((h == NULL) || (key == NULL)), -EINVAL);
 784         return __rte_hash_lookup_with_hash(h, key, sig, data);
 785 }
 786
 787 int
 788 rte_hash_lookup_data(const struct rte_hash *h, const void *key, void **data)
 789 {
 790         RETURN_IF_TRUE(((h == NULL) || (key == NULL)), -EINVAL);
 791         return __rte_hash_lookup_with_hash(h, key, rte_hash_hash(h, key), data);
 792 }
 793
 794 static inline void
 795 remove_entry(const struct rte_hash *h, struct rte_hash_bucket *bkt, unsigned i)
 796 {
 797         unsigned lcore_id, n_slots;
 798         struct lcore_cache *cached_free_slots;
 799
 800         bkt->sig_current[i] = NULL_SIGNATURE;
 801         bkt->sig_alt[i] = NULL_SIGNATURE;
 802         if (h->hw_trans_mem_support) {
 803                 lcore_id = rte_lcore_id();
 804                 cached_free_slots = &h->local_free_slots[lcore_id];
 805                 /* Cache full, need to free it. */
 806                 if (cached_free_slots->len == LCORE_CACHE_SIZE) {
 807                         /* Need to enqueue the free slots in global ring. */
 808                         n_slots = rte_ring_mp_enqueue_burst(h->free_slots,
 809                                                 cached_free_slots->objs,
 810                                                 LCORE_CACHE_SIZE);
 811                         cached_free_slots->len -= n_slots;
 812                 }
 813                 /* Put index of new free slot in cache. */
 814                 cached_free_slots->objs[cached_free_slots->len] =
 815                                 (void *)((uintptr_t)bkt->key_idx[i]);
 816                 cached_free_slots->len++;
 817         } else {
 818                 rte_ring_sp_enqueue(h->free_slots,
 819                                 (void *)((uintptr_t)bkt->key_idx[i]));
 820         }
 821 }
 822
 823 static inline int32_t
 824 __rte_hash_del_key_with_hash(const struct rte_hash *h, const void *key,
 825                                                 hash_sig_t sig)
 826 {
 827         uint32_t bucket_idx;
 828         hash_sig_t alt_hash;
 829         unsigned i;
 830         struct rte_hash_bucket *bkt;
 831         struct rte_hash_key *k, *keys = h->key_store;
 832         int32_t ret;
 833
 834         bucket_idx = sig & h->bucket_bitmask;
 835         bkt = &h->buckets[bucket_idx];
 836
 837         /* Check if key is in primary location */
 838         for (i = 0; i < RTE_HASH_BUCKET_ENTRIES; i++) {
 839                 if (bkt->sig_current[i] == sig &&
 840                                 bkt->key_idx[i] != EMPTY_SLOT) {
 841                         k = (struct rte_hash_key *) ((char *)keys +
 842                                         bkt->key_idx[i] * h->key_entry_size);
 843                         if (rte_hash_cmp_eq(key, k->key, h) == 0) {
 844                                 remove_entry(h, bkt, i);
 845
 846                                 /*
 847                                  * Return index where key is stored,
 848                                  * substracting the first dummy index
 849                                  */
 850                                 ret = bkt->key_idx[i] - 1;
 851                                 bkt->key_idx[i] = EMPTY_SLOT;
 852                                 return ret;
 853                         }
 854                 }
 855         }
 856
 857         /* Calculate secondary hash */
 858         alt_hash = rte_hash_secondary_hash(sig);
 859         bucket_idx = alt_hash & h->bucket_bitmask;
 860         bkt = &h->buckets[bucket_idx];
 861
 862         /* Check if key is in secondary location */
 863         for (i = 0; i < RTE_HASH_BUCKET_ENTRIES; i++) {
 864                 if (bkt->sig_current[i] == alt_hash &&
 865                                 bkt->key_idx[i] != EMPTY_SLOT) {
 866                         k = (struct rte_hash_key *) ((char *)keys +
 867                                         bkt->key_idx[i] * h->key_entry_size);
 868                         if (rte_hash_cmp_eq(key, k->key, h) == 0) {
 869                                 remove_entry(h, bkt, i);
 870
 871                                 /*
 872                                  * Return index where key is stored,
 873                                  * substracting the first dummy index
 874                                  */
 875                                 ret = bkt->key_idx[i] - 1;
 876                                 bkt->key_idx[i] = EMPTY_SLOT;
 877                                 return ret;
 878                         }
 879                 }
 880         }
 881
 882         return -ENOENT;
 883 }
 884
 885 int32_t
 886 rte_hash_del_key_with_hash(const struct rte_hash *h,
 887                         const void *key, hash_sig_t sig)
 888 {
 889         RETURN_IF_TRUE(((h == NULL) || (key == NULL)), -EINVAL);
 890         return __rte_hash_del_key_with_hash(h, key, sig);
 891 }
 892
 893 int32_t
 894 rte_hash_del_key(const struct rte_hash *h, const void *key)
 895 {
 896         RETURN_IF_TRUE(((h == NULL) || (key == NULL)), -EINVAL);
 897         return __rte_hash_del_key_with_hash(h, key, rte_hash_hash(h, key));
 898 }
 899
 900 int
 901 rte_hash_get_key_with_position(const struct rte_hash *h, const int32_t position,
 902                                void **key)
 903 {
 904         RETURN_IF_TRUE(((h == NULL) || (key == NULL)), -EINVAL);
 905
 906         struct rte_hash_key *k, *keys = h->key_store;
 907         k = (struct rte_hash_key *) ((char *) keys + (position + 1) *
 908                                      h->key_entry_size);
 909         *key = k->key;
 910
 911         if (position !=
 912             __rte_hash_lookup_with_hash(h, *key, rte_hash_hash(h, *key),
 913                                         NULL)) {
 914                 return -ENOENT;
 915         }
 916
 917         return 0;
 918 }
 919
 920 static inline void
 921 compare_signatures(uint32_t *prim_hash_matches, uint32_t *sec_hash_matches,
 922                         const struct rte_hash_bucket *prim_bkt,
 923                         const struct rte_hash_bucket *sec_bkt,
 924                         hash_sig_t prim_hash, hash_sig_t sec_hash,
 925                         enum rte_hash_sig_compare_function sig_cmp_fn)
 926 {
 927         unsigned int i;
 928
 929         switch (sig_cmp_fn) {
 930 #ifdef RTE_MACHINE_CPUFLAG_AVX2
 931         case RTE_HASH_COMPARE_AVX2:
 932                 *prim_hash_matches = _mm256_movemask_ps((__m256)_mm256_cmpeq_epi32(
 933                                 _mm256_load_si256(
 934                                         (__m256i const *)prim_bkt->sig_current),
 935                                 _mm256_set1_epi32(prim_hash)));
 936                 *sec_hash_matches = _mm256_movemask_ps((__m256)_mm256_cmpeq_epi32(
 937                                 _mm256_load_si256(
 938                                         (__m256i const *)sec_bkt->sig_current),
 939                                 _mm256_set1_epi32(sec_hash)));
 940                 break;
 941 #endif
 942 #ifdef RTE_MACHINE_CPUFLAG_SSE2
 943         case RTE_HASH_COMPARE_SSE:
 944                 /* Compare the first 4 signatures in the bucket */
 945                 *prim_hash_matches = _mm_movemask_ps((__m128)_mm_cmpeq_epi16(
 946                                 _mm_load_si128(
 947                                         (__m128i const *)prim_bkt->sig_current),
 948                                 _mm_set1_epi32(prim_hash)));
 949                 *prim_hash_matches |= (_mm_movemask_ps((__m128)_mm_cmpeq_epi16(
 950                                 _mm_load_si128(
 951                                         (__m128i const *)&prim_bkt->sig_current[4]),
 952                                 _mm_set1_epi32(prim_hash)))) << 4;
 953                 /* Compare the first 4 signatures in the bucket */
 954                 *sec_hash_matches = _mm_movemask_ps((__m128)_mm_cmpeq_epi16(
 955                                 _mm_load_si128(
 956                                         (__m128i const *)sec_bkt->sig_current),
 957                                 _mm_set1_epi32(sec_hash)));
 958                 *sec_hash_matches |= (_mm_movemask_ps((__m128)_mm_cmpeq_epi16(
 959                                 _mm_load_si128(
 960                                         (__m128i const *)&sec_bkt->sig_current[4]),
 961                                 _mm_set1_epi32(sec_hash)))) << 4;
 962                 break;
 963 #endif
 964         default:
 965                 for (i = 0; i < RTE_HASH_BUCKET_ENTRIES; i++) {
 966                         *prim_hash_matches |=
 967                                 ((prim_hash == prim_bkt->sig_current[i]) << i);
 968                         *sec_hash_matches |=
 969                                 ((sec_hash == sec_bkt->sig_current[i]) << i);
 970                 }
 971         }
 972
 973 }
 974
 975 #define PREFETCH_OFFSET 4
 976 static inline void
 977 __rte_hash_lookup_bulk(const struct rte_hash *h, const void **keys,
 978                         int32_t num_keys, int32_t *positions,
 979                         uint64_t *hit_mask, void *data[])
 980 {
 981         uint64_t hits = 0;
 982         int32_t i;
 983         uint32_t prim_hash[RTE_HASH_LOOKUP_BULK_MAX];
 984         uint32_t sec_hash[RTE_HASH_LOOKUP_BULK_MAX];
 985         const struct rte_hash_bucket *primary_bkt[RTE_HASH_LOOKUP_BULK_MAX];
 986         const struct rte_hash_bucket *secondary_bkt[RTE_HASH_LOOKUP_BULK_MAX];
 987         uint32_t prim_hitmask[RTE_HASH_LOOKUP_BULK_MAX] = {0};
 988         uint32_t sec_hitmask[RTE_HASH_LOOKUP_BULK_MAX] = {0};
 989
 990         /* Prefetch first keys */
 991         for (i = 0; i < PREFETCH_OFFSET && i < num_keys; i++)
 992                 rte_prefetch0(keys[i]);
 993
 994         /*
 995          * Prefetch rest of the keys, calculate primary and
 996          * secondary bucket and prefetch them
 997          */
 998         for (i = 0; i < (num_keys - PREFETCH_OFFSET); i++) {
 999                 rte_prefetch0(keys[i + PREFETCH_OFFSET]);
1000
1001                 prim_hash[i] = rte_hash_hash(h, keys[i]);
1002                 sec_hash[i] = rte_hash_secondary_hash(prim_hash[i]);
1003
1004                 primary_bkt[i] = &h->buckets[prim_hash[i] & h->bucket_bitmask];
1005                 secondary_bkt[i] = &h->buckets[sec_hash[i] & h->bucket_bitmask];
1006
1007                 rte_prefetch0(primary_bkt[i]);
1008                 rte_prefetch0(secondary_bkt[i]);
1009         }
1010
1011         /* Calculate and prefetch rest of the buckets */
1012         for (; i < num_keys; i++) {
1013                 prim_hash[i] = rte_hash_hash(h, keys[i]);
1014                 sec_hash[i] = rte_hash_secondary_hash(prim_hash[i]);
1015
1016                 primary_bkt[i] = &h->buckets[prim_hash[i] & h->bucket_bitmask];
1017                 secondary_bkt[i] = &h->buckets[sec_hash[i] & h->bucket_bitmask];
1018
1019                 rte_prefetch0(primary_bkt[i]);
1020                 rte_prefetch0(secondary_bkt[i]);
1021         }
1022
1023         /* Compare signatures and prefetch key slot of first hit */
1024         for (i = 0; i < num_keys; i++) {
1025                 compare_signatures(&prim_hitmask[i], &sec_hitmask[i],
1026                                 primary_bkt[i], secondary_bkt[i],
1027                                 prim_hash[i], sec_hash[i], h->sig_cmp_fn);
1028
1029                 if (prim_hitmask[i]) {
1030                         uint32_t first_hit = __builtin_ctzl(prim_hitmask[i]);
1031                         uint32_t key_idx = primary_bkt[i]->key_idx[first_hit];
1032                         const struct rte_hash_key *key_slot =
1033                                 (const struct rte_hash_key *)(
1034                                 (const char *)h->key_store +
1035                                 key_idx * h->key_entry_size);
1036                         rte_prefetch0(key_slot);
1037                         continue;
1038                 }
1039
1040                 if (sec_hitmask[i]) {
1041                         uint32_t first_hit = __builtin_ctzl(sec_hitmask[i]);
1042                         uint32_t key_idx = secondary_bkt[i]->key_idx[first_hit];
1043                         const struct rte_hash_key *key_slot =
1044                                 (const struct rte_hash_key *)(
1045                                 (const char *)h->key_store +
1046                                 key_idx * h->key_entry_size);
1047                         rte_prefetch0(key_slot);
1048                 }
1049         }
1050
1051         /* Compare keys, first hits in primary first */
1052         for (i = 0; i < num_keys; i++) {
1053                 positions[i] = -ENOENT;
1054                 while (prim_hitmask[i]) {
1055                         uint32_t hit_index = __builtin_ctzl(prim_hitmask[i]);
1056
1057                         uint32_t key_idx = primary_bkt[i]->key_idx[hit_index];
1058                         const struct rte_hash_key *key_slot =
1059                                 (const struct rte_hash_key *)(
1060                                 (const char *)h->key_store +
1061                                 key_idx * h->key_entry_size);
1062                         /*
1063                          * If key index is 0, do not compare key,
1064                          * as it is checking the dummy slot
1065                          */
1066                         if (!!key_idx & !rte_hash_cmp_eq(key_slot->key, keys[i], h)) {
1067                                 if (data != NULL)
1068                                         data[i] = key_slot->pdata;
1069
1070                                 hits |= 1ULL << i;
1071                                 positions[i] = key_idx - 1;
1072                                 goto next_key;
1073                         }
1074                         prim_hitmask[i] &= ~(1 << (hit_index));
1075                 }
1076
1077                 while (sec_hitmask[i]) {
1078                         uint32_t hit_index = __builtin_ctzl(sec_hitmask[i]);
1079
1080                         uint32_t key_idx = secondary_bkt[i]->key_idx[hit_index];
1081                         const struct rte_hash_key *key_slot =
1082                                 (const struct rte_hash_key *)(
1083                                 (const char *)h->key_store +
1084                                 key_idx * h->key_entry_size);
1085                         /*
1086                          * If key index is 0, do not compare key,
1087                          * as it is checking the dummy slot
1088                          */
1089
1090                         if (!!key_idx & !rte_hash_cmp_eq(key_slot->key, keys[i], h)) {
1091                                 if (data != NULL)
1092                                         data[i] = key_slot->pdata;
1093
1094                                 hits |= 1ULL << i;
1095                                 positions[i] = key_idx - 1;
1096                                 goto next_key;
1097                         }
1098                         sec_hitmask[i] &= ~(1 << (hit_index));
1099                 }
1100
1101 next_key:
1102                 continue;
1103         }
1104
1105         if (hit_mask != NULL)
1106                 *hit_mask = hits;
1107 }
1108
1109 int
1110 rte_hash_lookup_bulk(const struct rte_hash *h, const void **keys,
1111                       uint32_t num_keys, int32_t *positions)
1112 {
1113         RETURN_IF_TRUE(((h == NULL) || (keys == NULL) || (num_keys == 0) ||
1114                         (num_keys > RTE_HASH_LOOKUP_BULK_MAX) ||
1115                         (positions == NULL)), -EINVAL);
1116
1117         __rte_hash_lookup_bulk(h, keys, num_keys, positions, NULL, NULL);
1118         return 0;
1119 }
1120
1121 int
1122 rte_hash_lookup_bulk_data(const struct rte_hash *h, const void **keys,
1123                       uint32_t num_keys, uint64_t *hit_mask, void *data[])
1124 {
1125         RETURN_IF_TRUE(((h == NULL) || (keys == NULL) || (num_keys == 0) ||
1126                         (num_keys > RTE_HASH_LOOKUP_BULK_MAX) ||
1127                         (hit_mask == NULL)), -EINVAL);
1128
1129         int32_t positions[num_keys];
1130
1131         __rte_hash_lookup_bulk(h, keys, num_keys, positions, hit_mask, data);
1132
1133         /* Return number of hits */
1134         return __builtin_popcountl(*hit_mask);
1135 }
1136
1137 int32_t
1138 rte_hash_iterate(const struct rte_hash *h, const void **key, void **data, uint32_t *next)
1139 {
1140         uint32_t bucket_idx, idx, position;
1141         struct rte_hash_key *next_key;
1142
1143         RETURN_IF_TRUE(((h == NULL) || (next == NULL)), -EINVAL);
1144
1145         const uint32_t total_entries = h->num_buckets * RTE_HASH_BUCKET_ENTRIES;
1146         /* Out of bounds */
1147         if (*next >= total_entries)
1148                 return -ENOENT;
1149
1150         /* Calculate bucket and index of current iterator */
1151         bucket_idx = *next / RTE_HASH_BUCKET_ENTRIES;
1152         idx = *next % RTE_HASH_BUCKET_ENTRIES;
1153
1154         /* If current position is empty, go to the next one */
1155         while (h->buckets[bucket_idx].key_idx[idx] == EMPTY_SLOT) {
1156                 (*next)++;
1157                 /* End of table */
1158                 if (*next == total_entries)
1159                         return -ENOENT;
1160                 bucket_idx = *next / RTE_HASH_BUCKET_ENTRIES;
1161                 idx = *next % RTE_HASH_BUCKET_ENTRIES;
1162         }
1163
1164         /* Get position of entry in key table */
1165         position = h->buckets[bucket_idx].key_idx[idx];
1166         next_key = (struct rte_hash_key *) ((char *)h->key_store +
1167                                 position * h->key_entry_size);
1168         /* Return key and data */
1169         *key = next_key->key;
1170         *data = next_key->pdata;
1171
1172         /* Increment iterator */
1173         (*next)++;
1174
1175         return position - 1;
1176 }