lib/librte_hash/rte_cuckoo_hash.c

   1 /* SPDX-License-Identifier: BSD-3-Clause
   2  * Copyright(c) 2010-2016 Intel Corporation
   3  * Copyright(c) 2018 Arm Limited
   4  */
   5
   6 #include <string.h>
   7 #include <stdint.h>
   8 #include <errno.h>
   9 #include <stdio.h>
  10 #include <stdarg.h>
  11 #include <sys/queue.h>
  12
  13 #include <rte_common.h>
  14 #include <rte_memory.h>         /* for definition of RTE_CACHE_LINE_SIZE */
  15 #include <rte_log.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_elem.h>
  28 #include <rte_compat.h>
  29 #include <rte_vect.h>
  30 #include <rte_tailq.h>
  31
  32 #include "rte_hash.h"
  33 #include "rte_cuckoo_hash.h"
  34
  35 #define FOR_EACH_BUCKET(CURRENT_BKT, START_BUCKET)                            \
  36         for (CURRENT_BKT = START_BUCKET;                                      \
  37                 CURRENT_BKT != NULL;                                          \
  38                 CURRENT_BKT = CURRENT_BKT->next)
  39
  40 TAILQ_HEAD(rte_hash_list, rte_tailq_entry);
  41
  42 static struct rte_tailq_elem rte_hash_tailq = {
  43         .name = "RTE_HASH",
  44 };
  45 EAL_REGISTER_TAILQ(rte_hash_tailq)
  46
  47 struct rte_hash *
  48 rte_hash_find_existing(const char *name)
  49 {
  50         struct rte_hash *h = NULL;
  51         struct rte_tailq_entry *te;
  52         struct rte_hash_list *hash_list;
  53
  54         hash_list = RTE_TAILQ_CAST(rte_hash_tailq.head, rte_hash_list);
  55
  56         rte_mcfg_tailq_read_lock();
  57         TAILQ_FOREACH(te, hash_list, next) {
  58                 h = (struct rte_hash *) te->data;
  59                 if (strncmp(name, h->name, RTE_HASH_NAMESIZE) == 0)
  60                         break;
  61         }
  62         rte_mcfg_tailq_read_unlock();
  63
  64         if (te == NULL) {
  65                 rte_errno = ENOENT;
  66                 return NULL;
  67         }
  68         return h;
  69 }
  70
  71 static inline struct rte_hash_bucket *
  72 rte_hash_get_last_bkt(struct rte_hash_bucket *lst_bkt)
  73 {
  74         while (lst_bkt->next != NULL)
  75                 lst_bkt = lst_bkt->next;
  76         return lst_bkt;
  77 }
  78
  79 void rte_hash_set_cmp_func(struct rte_hash *h, rte_hash_cmp_eq_t func)
  80 {
  81         h->cmp_jump_table_idx = KEY_CUSTOM;
  82         h->rte_hash_custom_cmp_eq = func;
  83 }
  84
  85 static inline int
  86 rte_hash_cmp_eq(const void *key1, const void *key2, const struct rte_hash *h)
  87 {
  88         if (h->cmp_jump_table_idx == KEY_CUSTOM)
  89                 return h->rte_hash_custom_cmp_eq(key1, key2, h->key_len);
  90         else
  91                 return cmp_jump_table[h->cmp_jump_table_idx](key1, key2, h->key_len);
  92 }
  93
  94 /*
  95  * We use higher 16 bits of hash as the signature value stored in table.
  96  * We use the lower bits for the primary bucket
  97  * location. Then we XOR primary bucket location and the signature
  98  * to get the secondary bucket location. This is same as
  99  * proposed in Bin Fan, et al's paper
 100  * "MemC3: Compact and Concurrent MemCache with Dumber Caching and
 101  * Smarter Hashing". The benefit to use
 102  * XOR is that one could derive the alternative bucket location
 103  * by only using the current bucket location and the signature.
 104  */
 105 static inline uint16_t
 106 get_short_sig(const hash_sig_t hash)
 107 {
 108         return hash >> 16;
 109 }
 110
 111 static inline uint32_t
 112 get_prim_bucket_index(const struct rte_hash *h, const hash_sig_t hash)
 113 {
 114         return hash & h->bucket_bitmask;
 115 }
 116
 117 static inline uint32_t
 118 get_alt_bucket_index(const struct rte_hash *h,
 119                         uint32_t cur_bkt_idx, uint16_t sig)
 120 {
 121         return (cur_bkt_idx ^ sig) & h->bucket_bitmask;
 122 }
 123
 124 struct rte_hash *
 125 rte_hash_create(const struct rte_hash_parameters *params)
 126 {
 127         struct rte_hash *h = NULL;
 128         struct rte_tailq_entry *te = NULL;
 129         struct rte_hash_list *hash_list;
 130         struct rte_ring *r = NULL;
 131         struct rte_ring *r_ext = NULL;
 132         char hash_name[RTE_HASH_NAMESIZE];
 133         void *k = NULL;
 134         void *buckets = NULL;
 135         void *buckets_ext = NULL;
 136         char ring_name[RTE_RING_NAMESIZE];
 137         char ext_ring_name[RTE_RING_NAMESIZE];
 138         unsigned num_key_slots;
 139         unsigned int hw_trans_mem_support = 0, use_local_cache = 0;
 140         unsigned int ext_table_support = 0;
 141         unsigned int readwrite_concur_support = 0;
 142         unsigned int writer_takes_lock = 0;
 143         unsigned int no_free_on_del = 0;
 144         uint32_t *ext_bkt_to_free = NULL;
 145         uint32_t *tbl_chng_cnt = NULL;
 146         unsigned int readwrite_concur_lf_support = 0;
 147         uint32_t i;
 148
 149         rte_hash_function default_hash_func = (rte_hash_function)rte_jhash;
 150
 151         hash_list = RTE_TAILQ_CAST(rte_hash_tailq.head, rte_hash_list);
 152
 153         if (params == NULL) {
 154                 RTE_LOG(ERR, HASH, "rte_hash_create has no parameters\n");
 155                 return NULL;
 156         }
 157
 158         /* Check for valid parameters */
 159         if ((params->entries > RTE_HASH_ENTRIES_MAX) ||
 160                         (params->entries < RTE_HASH_BUCKET_ENTRIES) ||
 161                         (params->key_len == 0)) {
 162                 rte_errno = EINVAL;
 163                 RTE_LOG(ERR, HASH, "rte_hash_create has invalid parameters\n");
 164                 return NULL;
 165         }
 166
 167         /* Validate correct usage of extra options */
 168         if ((params->extra_flag & RTE_HASH_EXTRA_FLAGS_RW_CONCURRENCY) &&
 169             (params->extra_flag & RTE_HASH_EXTRA_FLAGS_RW_CONCURRENCY_LF)) {
 170                 rte_errno = EINVAL;
 171                 RTE_LOG(ERR, HASH, "rte_hash_create: choose rw concurrency or "
 172                         "rw concurrency lock free\n");
 173                 return NULL;
 174         }
 175
 176         /* Check extra flags field to check extra options. */
 177         if (params->extra_flag & RTE_HASH_EXTRA_FLAGS_TRANS_MEM_SUPPORT)
 178                 hw_trans_mem_support = 1;
 179
 180         if (params->extra_flag & RTE_HASH_EXTRA_FLAGS_MULTI_WRITER_ADD) {
 181                 use_local_cache = 1;
 182                 writer_takes_lock = 1;
 183         }
 184
 185         if (params->extra_flag & RTE_HASH_EXTRA_FLAGS_RW_CONCURRENCY) {
 186                 readwrite_concur_support = 1;
 187                 writer_takes_lock = 1;
 188         }
 189
 190         if (params->extra_flag & RTE_HASH_EXTRA_FLAGS_EXT_TABLE)
 191                 ext_table_support = 1;
 192
 193         if (params->extra_flag & RTE_HASH_EXTRA_FLAGS_NO_FREE_ON_DEL)
 194                 no_free_on_del = 1;
 195
 196         if (params->extra_flag & RTE_HASH_EXTRA_FLAGS_RW_CONCURRENCY_LF) {
 197                 readwrite_concur_lf_support = 1;
 198                 /* Enable not freeing internal memory/index on delete */
 199                 no_free_on_del = 1;
 200         }
 201
 202         /* Store all keys and leave the first entry as a dummy entry for lookup_bulk */
 203         if (use_local_cache)
 204                 /*
 205                  * Increase number of slots by total number of indices
 206                  * that can be stored in the lcore caches
 207                  * except for the first cache
 208                  */
 209                 num_key_slots = params->entries + (RTE_MAX_LCORE - 1) *
 210                                         (LCORE_CACHE_SIZE - 1) + 1;
 211         else
 212                 num_key_slots = params->entries + 1;
 213
 214         snprintf(ring_name, sizeof(ring_name), "HT_%s", params->name);
 215         /* Create ring (Dummy slot index is not enqueued) */
 216         r = rte_ring_create_elem(ring_name, sizeof(uint32_t),
 217                         rte_align32pow2(num_key_slots), params->socket_id, 0);
 218         if (r == NULL) {
 219                 RTE_LOG(ERR, HASH, "memory allocation failed\n");
 220                 goto err;
 221         }
 222
 223         const uint32_t num_buckets = rte_align32pow2(params->entries) /
 224                                                 RTE_HASH_BUCKET_ENTRIES;
 225
 226         /* Create ring for extendable buckets. */
 227         if (ext_table_support) {
 228                 snprintf(ext_ring_name, sizeof(ext_ring_name), "HT_EXT_%s",
 229                                                                 params->name);
 230                 r_ext = rte_ring_create_elem(ext_ring_name, sizeof(uint32_t),
 231                                 rte_align32pow2(num_buckets + 1),
 232                                 params->socket_id, 0);
 233
 234                 if (r_ext == NULL) {
 235                         RTE_LOG(ERR, HASH, "ext buckets memory allocation "
 236                                                                 "failed\n");
 237                         goto err;
 238                 }
 239         }
 240
 241         snprintf(hash_name, sizeof(hash_name), "HT_%s", params->name);
 242
 243         rte_mcfg_tailq_write_lock();
 244
 245         /* guarantee there's no existing: this is normally already checked
 246          * by ring creation above */
 247         TAILQ_FOREACH(te, hash_list, next) {
 248                 h = (struct rte_hash *) te->data;
 249                 if (strncmp(params->name, h->name, RTE_HASH_NAMESIZE) == 0)
 250                         break;
 251         }
 252         h = NULL;
 253         if (te != NULL) {
 254                 rte_errno = EEXIST;
 255                 te = NULL;
 256                 goto err_unlock;
 257         }
 258
 259         te = rte_zmalloc("HASH_TAILQ_ENTRY", sizeof(*te), 0);
 260         if (te == NULL) {
 261                 RTE_LOG(ERR, HASH, "tailq entry allocation failed\n");
 262                 goto err_unlock;
 263         }
 264
 265         h = (struct rte_hash *)rte_zmalloc_socket(hash_name, sizeof(struct rte_hash),
 266                                         RTE_CACHE_LINE_SIZE, params->socket_id);
 267
 268         if (h == NULL) {
 269                 RTE_LOG(ERR, HASH, "memory allocation failed\n");
 270                 goto err_unlock;
 271         }
 272
 273         buckets = rte_zmalloc_socket(NULL,
 274                                 num_buckets * sizeof(struct rte_hash_bucket),
 275                                 RTE_CACHE_LINE_SIZE, params->socket_id);
 276
 277         if (buckets == NULL) {
 278                 RTE_LOG(ERR, HASH, "buckets memory allocation failed\n");
 279                 goto err_unlock;
 280         }
 281
 282         /* Allocate same number of extendable buckets */
 283         if (ext_table_support) {
 284                 buckets_ext = rte_zmalloc_socket(NULL,
 285                                 num_buckets * sizeof(struct rte_hash_bucket),
 286                                 RTE_CACHE_LINE_SIZE, params->socket_id);
 287                 if (buckets_ext == NULL) {
 288                         RTE_LOG(ERR, HASH, "ext buckets memory allocation "
 289                                                         "failed\n");
 290                         goto err_unlock;
 291                 }
 292                 /* Populate ext bkt ring. We reserve 0 similar to the
 293                  * key-data slot, just in case in future we want to
 294                  * use bucket index for the linked list and 0 means NULL
 295                  * for next bucket
 296                  */
 297                 for (i = 1; i <= num_buckets; i++)
 298                         rte_ring_sp_enqueue_elem(r_ext, &i, sizeof(uint32_t));
 299
 300                 if (readwrite_concur_lf_support) {
 301                         ext_bkt_to_free = rte_zmalloc(NULL, sizeof(uint32_t) *
 302                                                                 num_key_slots, 0);
 303                         if (ext_bkt_to_free == NULL) {
 304                                 RTE_LOG(ERR, HASH, "ext bkt to free memory allocation "
 305                                                                 "failed\n");
 306                                 goto err_unlock;
 307                         }
 308                 }
 309         }
 310
 311         const uint32_t key_entry_size =
 312                 RTE_ALIGN(sizeof(struct rte_hash_key) + params->key_len,
 313                           KEY_ALIGNMENT);
 314         const uint64_t key_tbl_size = (uint64_t) key_entry_size * num_key_slots;
 315
 316         k = rte_zmalloc_socket(NULL, key_tbl_size,
 317                         RTE_CACHE_LINE_SIZE, params->socket_id);
 318
 319         if (k == NULL) {
 320                 RTE_LOG(ERR, HASH, "memory allocation failed\n");
 321                 goto err_unlock;
 322         }
 323
 324         tbl_chng_cnt = rte_zmalloc_socket(NULL, sizeof(uint32_t),
 325                         RTE_CACHE_LINE_SIZE, params->socket_id);
 326
 327         if (tbl_chng_cnt == NULL) {
 328                 RTE_LOG(ERR, HASH, "memory allocation failed\n");
 329                 goto err_unlock;
 330         }
 331
 332 /*
 333  * If x86 architecture is used, select appropriate compare function,
 334  * which may use x86 intrinsics, otherwise use memcmp
 335  */
 336 #if defined(RTE_ARCH_X86) || defined(RTE_ARCH_ARM64)
 337         /* Select function to compare keys */
 338         switch (params->key_len) {
 339         case 16:
 340                 h->cmp_jump_table_idx = KEY_16_BYTES;
 341                 break;
 342         case 32:
 343                 h->cmp_jump_table_idx = KEY_32_BYTES;
 344                 break;
 345         case 48:
 346                 h->cmp_jump_table_idx = KEY_48_BYTES;
 347                 break;
 348         case 64:
 349                 h->cmp_jump_table_idx = KEY_64_BYTES;
 350                 break;
 351         case 80:
 352                 h->cmp_jump_table_idx = KEY_80_BYTES;
 353                 break;
 354         case 96:
 355                 h->cmp_jump_table_idx = KEY_96_BYTES;
 356                 break;
 357         case 112:
 358                 h->cmp_jump_table_idx = KEY_112_BYTES;
 359                 break;
 360         case 128:
 361                 h->cmp_jump_table_idx = KEY_128_BYTES;
 362                 break;
 363         default:
 364                 /* If key is not multiple of 16, use generic memcmp */
 365                 h->cmp_jump_table_idx = KEY_OTHER_BYTES;
 366         }
 367 #else
 368         h->cmp_jump_table_idx = KEY_OTHER_BYTES;
 369 #endif
 370
 371         if (use_local_cache) {
 372                 h->local_free_slots = rte_zmalloc_socket(NULL,
 373                                 sizeof(struct lcore_cache) * RTE_MAX_LCORE,
 374                                 RTE_CACHE_LINE_SIZE, params->socket_id);
 375         }
 376
 377         /* Default hash function */
 378 #if defined(RTE_ARCH_X86)
 379         default_hash_func = (rte_hash_function)rte_hash_crc;
 380 #elif defined(RTE_ARCH_ARM64)
 381         if (rte_cpu_get_flag_enabled(RTE_CPUFLAG_CRC32))
 382                 default_hash_func = (rte_hash_function)rte_hash_crc;
 383 #endif
 384         /* Setup hash context */
 385         strlcpy(h->name, params->name, sizeof(h->name));
 386         h->entries = params->entries;
 387         h->key_len = params->key_len;
 388         h->key_entry_size = key_entry_size;
 389         h->hash_func_init_val = params->hash_func_init_val;
 390
 391         h->num_buckets = num_buckets;
 392         h->bucket_bitmask = h->num_buckets - 1;
 393         h->buckets = buckets;
 394         h->buckets_ext = buckets_ext;
 395         h->free_ext_bkts = r_ext;
 396         h->hash_func = (params->hash_func == NULL) ?
 397                 default_hash_func : params->hash_func;
 398         h->key_store = k;
 399         h->free_slots = r;
 400         h->ext_bkt_to_free = ext_bkt_to_free;
 401         h->tbl_chng_cnt = tbl_chng_cnt;
 402         *h->tbl_chng_cnt = 0;
 403         h->hw_trans_mem_support = hw_trans_mem_support;
 404         h->use_local_cache = use_local_cache;
 405         h->readwrite_concur_support = readwrite_concur_support;
 406         h->ext_table_support = ext_table_support;
 407         h->writer_takes_lock = writer_takes_lock;
 408         h->no_free_on_del = no_free_on_del;
 409         h->readwrite_concur_lf_support = readwrite_concur_lf_support;
 410
 411 #if defined(RTE_ARCH_X86)
 412         if (rte_cpu_get_flag_enabled(RTE_CPUFLAG_SSE2))
 413                 h->sig_cmp_fn = RTE_HASH_COMPARE_SSE;
 414         else
 415 #elif defined(RTE_ARCH_ARM64)
 416         if (rte_cpu_get_flag_enabled(RTE_CPUFLAG_NEON))
 417                 h->sig_cmp_fn = RTE_HASH_COMPARE_NEON;
 418         else
 419 #endif
 420                 h->sig_cmp_fn = RTE_HASH_COMPARE_SCALAR;
 421
 422         /* Writer threads need to take the lock when:
 423          * 1) RTE_HASH_EXTRA_FLAGS_RW_CONCURRENCY is enabled OR
 424          * 2) RTE_HASH_EXTRA_FLAGS_MULTI_WRITER_ADD is enabled
 425          */
 426         if (h->writer_takes_lock) {
 427                 h->readwrite_lock = rte_malloc(NULL, sizeof(rte_rwlock_t),
 428                                                 RTE_CACHE_LINE_SIZE);
 429                 if (h->readwrite_lock == NULL)
 430                         goto err_unlock;
 431
 432                 rte_rwlock_init(h->readwrite_lock);
 433         }
 434
 435         /* Populate free slots ring. Entry zero is reserved for key misses. */
 436         for (i = 1; i < num_key_slots; i++)
 437                 rte_ring_sp_enqueue_elem(r, &i, sizeof(uint32_t));
 438
 439         te->data = (void *) h;
 440         TAILQ_INSERT_TAIL(hash_list, te, next);
 441         rte_mcfg_tailq_write_unlock();
 442
 443         return h;
 444 err_unlock:
 445         rte_mcfg_tailq_write_unlock();
 446 err:
 447         rte_ring_free(r);
 448         rte_ring_free(r_ext);
 449         rte_free(te);
 450         rte_free(h);
 451         rte_free(buckets);
 452         rte_free(buckets_ext);
 453         rte_free(k);
 454         rte_free(tbl_chng_cnt);
 455         rte_free(ext_bkt_to_free);
 456         return NULL;
 457 }
 458
 459 void
 460 rte_hash_free(struct rte_hash *h)
 461 {
 462         struct rte_tailq_entry *te;
 463         struct rte_hash_list *hash_list;
 464
 465         if (h == NULL)
 466                 return;
 467
 468         hash_list = RTE_TAILQ_CAST(rte_hash_tailq.head, rte_hash_list);
 469
 470         rte_mcfg_tailq_write_lock();
 471
 472         /* find out tailq entry */
 473         TAILQ_FOREACH(te, hash_list, next) {
 474                 if (te->data == (void *) h)
 475                         break;
 476         }
 477
 478         if (te == NULL) {
 479                 rte_mcfg_tailq_write_unlock();
 480                 return;
 481         }
 482
 483         TAILQ_REMOVE(hash_list, te, next);
 484
 485         rte_mcfg_tailq_write_unlock();
 486
 487         if (h->use_local_cache)
 488                 rte_free(h->local_free_slots);
 489         if (h->writer_takes_lock)
 490                 rte_free(h->readwrite_lock);
 491         rte_ring_free(h->free_slots);
 492         rte_ring_free(h->free_ext_bkts);
 493         rte_free(h->key_store);
 494         rte_free(h->buckets);
 495         rte_free(h->buckets_ext);
 496         rte_free(h->tbl_chng_cnt);
 497         rte_free(h->ext_bkt_to_free);
 498         rte_free(h);
 499         rte_free(te);
 500 }
 501
 502 hash_sig_t
 503 rte_hash_hash(const struct rte_hash *h, const void *key)
 504 {
 505         /* calc hash result by key */
 506         return h->hash_func(key, h->key_len, h->hash_func_init_val);
 507 }
 508
 509 int32_t
 510 rte_hash_max_key_id(const struct rte_hash *h)
 511 {
 512         RETURN_IF_TRUE((h == NULL), -EINVAL);
 513         if (h->use_local_cache)
 514                 /*
 515                  * Increase number of slots by total number of indices
 516                  * that can be stored in the lcore caches
 517                  */
 518                 return (h->entries + ((RTE_MAX_LCORE - 1) *
 519                                         (LCORE_CACHE_SIZE - 1)));
 520         else
 521                 return h->entries;
 522 }
 523
 524 int32_t
 525 rte_hash_count(const struct rte_hash *h)
 526 {
 527         uint32_t tot_ring_cnt, cached_cnt = 0;
 528         uint32_t i, ret;
 529
 530         if (h == NULL)
 531                 return -EINVAL;
 532
 533         if (h->use_local_cache) {
 534                 tot_ring_cnt = h->entries + (RTE_MAX_LCORE - 1) *
 535                                         (LCORE_CACHE_SIZE - 1);
 536                 for (i = 0; i < RTE_MAX_LCORE; i++)
 537                         cached_cnt += h->local_free_slots[i].len;
 538
 539                 ret = tot_ring_cnt - rte_ring_count(h->free_slots) -
 540                                                                 cached_cnt;
 541         } else {
 542                 tot_ring_cnt = h->entries;
 543                 ret = tot_ring_cnt - rte_ring_count(h->free_slots);
 544         }
 545         return ret;
 546 }
 547
 548 /* Read write locks implemented using rte_rwlock */
 549 static inline void
 550 __hash_rw_writer_lock(const struct rte_hash *h)
 551 {
 552         if (h->writer_takes_lock && h->hw_trans_mem_support)
 553                 rte_rwlock_write_lock_tm(h->readwrite_lock);
 554         else if (h->writer_takes_lock)
 555                 rte_rwlock_write_lock(h->readwrite_lock);
 556 }
 557
 558 static inline void
 559 __hash_rw_reader_lock(const struct rte_hash *h)
 560 {
 561         if (h->readwrite_concur_support && h->hw_trans_mem_support)
 562                 rte_rwlock_read_lock_tm(h->readwrite_lock);
 563         else if (h->readwrite_concur_support)
 564                 rte_rwlock_read_lock(h->readwrite_lock);
 565 }
 566
 567 static inline void
 568 __hash_rw_writer_unlock(const struct rte_hash *h)
 569 {
 570         if (h->writer_takes_lock && h->hw_trans_mem_support)
 571                 rte_rwlock_write_unlock_tm(h->readwrite_lock);
 572         else if (h->writer_takes_lock)
 573                 rte_rwlock_write_unlock(h->readwrite_lock);
 574 }
 575
 576 static inline void
 577 __hash_rw_reader_unlock(const struct rte_hash *h)
 578 {
 579         if (h->readwrite_concur_support && h->hw_trans_mem_support)
 580                 rte_rwlock_read_unlock_tm(h->readwrite_lock);
 581         else if (h->readwrite_concur_support)
 582                 rte_rwlock_read_unlock(h->readwrite_lock);
 583 }
 584
 585 void
 586 rte_hash_reset(struct rte_hash *h)
 587 {
 588         uint32_t tot_ring_cnt, i;
 589
 590         if (h == NULL)
 591                 return;
 592
 593         __hash_rw_writer_lock(h);
 594         memset(h->buckets, 0, h->num_buckets * sizeof(struct rte_hash_bucket));
 595         memset(h->key_store, 0, h->key_entry_size * (h->entries + 1));
 596         *h->tbl_chng_cnt = 0;
 597
 598         /* reset the free ring */
 599         rte_ring_reset(h->free_slots);
 600
 601         /* flush free extendable bucket ring and memory */
 602         if (h->ext_table_support) {
 603                 memset(h->buckets_ext, 0, h->num_buckets *
 604                                                 sizeof(struct rte_hash_bucket));
 605                 rte_ring_reset(h->free_ext_bkts);
 606         }
 607
 608         /* Repopulate the free slots ring. Entry zero is reserved for key misses */
 609         if (h->use_local_cache)
 610                 tot_ring_cnt = h->entries + (RTE_MAX_LCORE - 1) *
 611                                         (LCORE_CACHE_SIZE - 1);
 612         else
 613                 tot_ring_cnt = h->entries;
 614
 615         for (i = 1; i < tot_ring_cnt + 1; i++)
 616                 rte_ring_sp_enqueue_elem(h->free_slots, &i, sizeof(uint32_t));
 617
 618         /* Repopulate the free ext bkt ring. */
 619         if (h->ext_table_support) {
 620                 for (i = 1; i <= h->num_buckets; i++)
 621                         rte_ring_sp_enqueue_elem(h->free_ext_bkts, &i,
 622                                                         sizeof(uint32_t));
 623         }
 624
 625         if (h->use_local_cache) {
 626                 /* Reset local caches per lcore */
 627                 for (i = 0; i < RTE_MAX_LCORE; i++)
 628                         h->local_free_slots[i].len = 0;
 629         }
 630         __hash_rw_writer_unlock(h);
 631 }
 632
 633 /*
 634  * Function called to enqueue back an index in the cache/ring,
 635  * as slot has not being used and it can be used in the
 636  * next addition attempt.
 637  */
 638 static inline void
 639 enqueue_slot_back(const struct rte_hash *h,
 640                 struct lcore_cache *cached_free_slots,
 641                 uint32_t slot_id)
 642 {
 643         if (h->use_local_cache) {
 644                 cached_free_slots->objs[cached_free_slots->len] = slot_id;
 645                 cached_free_slots->len++;
 646         } else
 647                 rte_ring_sp_enqueue_elem(h->free_slots, &slot_id,
 648                                                 sizeof(uint32_t));
 649 }
 650
 651 /* Search a key from bucket and update its data.
 652  * Writer holds the lock before calling this.
 653  */
 654 static inline int32_t
 655 search_and_update(const struct rte_hash *h, void *data, const void *key,
 656         struct rte_hash_bucket *bkt, uint16_t sig)
 657 {
 658         int i;
 659         struct rte_hash_key *k, *keys = h->key_store;
 660
 661         for (i = 0; i < RTE_HASH_BUCKET_ENTRIES; i++) {
 662                 if (bkt->sig_current[i] == sig) {
 663                         k = (struct rte_hash_key *) ((char *)keys +
 664                                         bkt->key_idx[i] * h->key_entry_size);
 665                         if (rte_hash_cmp_eq(key, k->key, h) == 0) {
 666                                 /* The store to application data at *data
 667                                  * should not leak after the store to pdata
 668                                  * in the key store. i.e. pdata is the guard
 669                                  * variable. Release the application data
 670                                  * to the readers.
 671                                  */
 672                                 __atomic_store_n(&k->pdata,
 673                                         data,
 674                                         __ATOMIC_RELEASE);
 675                                 /*
 676                                  * Return index where key is stored,
 677                                  * subtracting the first dummy index
 678                                  */
 679                                 return bkt->key_idx[i] - 1;
 680                         }
 681                 }
 682         }
 683         return -1;
 684 }
 685
 686 /* Only tries to insert at one bucket (@prim_bkt) without trying to push
 687  * buckets around.
 688  * return 1 if matching existing key, return 0 if succeeds, return -1 for no
 689  * empty entry.
 690  */
 691 static inline int32_t
 692 rte_hash_cuckoo_insert_mw(const struct rte_hash *h,
 693                 struct rte_hash_bucket *prim_bkt,
 694                 struct rte_hash_bucket *sec_bkt,
 695                 const struct rte_hash_key *key, void *data,
 696                 uint16_t sig, uint32_t new_idx,
 697                 int32_t *ret_val)
 698 {
 699         unsigned int i;
 700         struct rte_hash_bucket *cur_bkt;
 701         int32_t ret;
 702
 703         __hash_rw_writer_lock(h);
 704         /* Check if key was inserted after last check but before this
 705          * protected region in case of inserting duplicated keys.
 706          */
 707         ret = search_and_update(h, data, key, prim_bkt, sig);
 708         if (ret != -1) {
 709                 __hash_rw_writer_unlock(h);
 710                 *ret_val = ret;
 711                 return 1;
 712         }
 713
 714         FOR_EACH_BUCKET(cur_bkt, sec_bkt) {
 715                 ret = search_and_update(h, data, key, cur_bkt, sig);
 716                 if (ret != -1) {
 717                         __hash_rw_writer_unlock(h);
 718                         *ret_val = ret;
 719                         return 1;
 720                 }
 721         }
 722
 723         /* Insert new entry if there is room in the primary
 724          * bucket.
 725          */
 726         for (i = 0; i < RTE_HASH_BUCKET_ENTRIES; i++) {
 727                 /* Check if slot is available */
 728                 if (likely(prim_bkt->key_idx[i] == EMPTY_SLOT)) {
 729                         prim_bkt->sig_current[i] = sig;
 730                         /* Store to signature and key should not
 731                          * leak after the store to key_idx. i.e.
 732                          * key_idx is the guard variable for signature
 733                          * and key.
 734                          */
 735                         __atomic_store_n(&prim_bkt->key_idx[i],
 736                                          new_idx,
 737                                          __ATOMIC_RELEASE);
 738                         break;
 739                 }
 740         }
 741         __hash_rw_writer_unlock(h);
 742
 743         if (i != RTE_HASH_BUCKET_ENTRIES)
 744                 return 0;
 745
 746         /* no empty entry */
 747         return -1;
 748 }
 749
 750 /* Shift buckets along provided cuckoo_path (@leaf and @leaf_slot) and fill
 751  * the path head with new entry (sig, alt_hash, new_idx)
 752  * return 1 if matched key found, return -1 if cuckoo path invalided and fail,
 753  * return 0 if succeeds.
 754  */
 755 static inline int
 756 rte_hash_cuckoo_move_insert_mw(const struct rte_hash *h,
 757                         struct rte_hash_bucket *bkt,
 758                         struct rte_hash_bucket *alt_bkt,
 759                         const struct rte_hash_key *key, void *data,
 760                         struct queue_node *leaf, uint32_t leaf_slot,
 761                         uint16_t sig, uint32_t new_idx,
 762                         int32_t *ret_val)
 763 {
 764         uint32_t prev_alt_bkt_idx;
 765         struct rte_hash_bucket *cur_bkt;
 766         struct queue_node *prev_node, *curr_node = leaf;
 767         struct rte_hash_bucket *prev_bkt, *curr_bkt = leaf->bkt;
 768         uint32_t prev_slot, curr_slot = leaf_slot;
 769         int32_t ret;
 770
 771         __hash_rw_writer_lock(h);
 772
 773         /* In case empty slot was gone before entering protected region */
 774         if (curr_bkt->key_idx[curr_slot] != EMPTY_SLOT) {
 775                 __hash_rw_writer_unlock(h);
 776                 return -1;
 777         }
 778
 779         /* Check if key was inserted after last check but before this
 780          * protected region.
 781          */
 782         ret = search_and_update(h, data, key, bkt, sig);
 783         if (ret != -1) {
 784                 __hash_rw_writer_unlock(h);
 785                 *ret_val = ret;
 786                 return 1;
 787         }
 788
 789         FOR_EACH_BUCKET(cur_bkt, alt_bkt) {
 790                 ret = search_and_update(h, data, key, cur_bkt, sig);
 791                 if (ret != -1) {
 792                         __hash_rw_writer_unlock(h);
 793                         *ret_val = ret;
 794                         return 1;
 795                 }
 796         }
 797
 798         while (likely(curr_node->prev != NULL)) {
 799                 prev_node = curr_node->prev;
 800                 prev_bkt = prev_node->bkt;
 801                 prev_slot = curr_node->prev_slot;
 802
 803                 prev_alt_bkt_idx = get_alt_bucket_index(h,
 804                                         prev_node->cur_bkt_idx,
 805                                         prev_bkt->sig_current[prev_slot]);
 806
 807                 if (unlikely(&h->buckets[prev_alt_bkt_idx]
 808                                 != curr_bkt)) {
 809                         /* revert it to empty, otherwise duplicated keys */
 810                         __atomic_store_n(&curr_bkt->key_idx[curr_slot],
 811                                 EMPTY_SLOT,
 812                                 __ATOMIC_RELEASE);
 813                         __hash_rw_writer_unlock(h);
 814                         return -1;
 815                 }
 816
 817                 if (h->readwrite_concur_lf_support) {
 818                         /* Inform the previous move. The current move need
 819                          * not be informed now as the current bucket entry
 820                          * is present in both primary and secondary.
 821                          * Since there is one writer, load acquires on
 822                          * tbl_chng_cnt are not required.
 823                          */
 824                         __atomic_store_n(h->tbl_chng_cnt,
 825                                          *h->tbl_chng_cnt + 1,
 826                                          __ATOMIC_RELEASE);
 827                         /* The store to sig_current should not
 828                          * move above the store to tbl_chng_cnt.
 829                          */
 830                         __atomic_thread_fence(__ATOMIC_RELEASE);
 831                 }
 832
 833                 /* Need to swap current/alt sig to allow later
 834                  * Cuckoo insert to move elements back to its
 835                  * primary bucket if available
 836                  */
 837                 curr_bkt->sig_current[curr_slot] =
 838                         prev_bkt->sig_current[prev_slot];
 839                 /* Release the updated bucket entry */
 840                 __atomic_store_n(&curr_bkt->key_idx[curr_slot],
 841                         prev_bkt->key_idx[prev_slot],
 842                         __ATOMIC_RELEASE);
 843
 844                 curr_slot = prev_slot;
 845                 curr_node = prev_node;
 846                 curr_bkt = curr_node->bkt;
 847         }
 848
 849         if (h->readwrite_concur_lf_support) {
 850                 /* Inform the previous move. The current move need
 851                  * not be informed now as the current bucket entry
 852                  * is present in both primary and secondary.
 853                  * Since there is one writer, load acquires on
 854                  * tbl_chng_cnt are not required.
 855                  */
 856                 __atomic_store_n(h->tbl_chng_cnt,
 857                                  *h->tbl_chng_cnt + 1,
 858                                  __ATOMIC_RELEASE);
 859                 /* The store to sig_current should not
 860                  * move above the store to tbl_chng_cnt.
 861                  */
 862                 __atomic_thread_fence(__ATOMIC_RELEASE);
 863         }
 864
 865         curr_bkt->sig_current[curr_slot] = sig;
 866         /* Release the new bucket entry */
 867         __atomic_store_n(&curr_bkt->key_idx[curr_slot],
 868                          new_idx,
 869                          __ATOMIC_RELEASE);
 870
 871         __hash_rw_writer_unlock(h);
 872
 873         return 0;
 874
 875 }
 876
 877 /*
 878  * Make space for new key, using bfs Cuckoo Search and Multi-Writer safe
 879  * Cuckoo
 880  */
 881 static inline int
 882 rte_hash_cuckoo_make_space_mw(const struct rte_hash *h,
 883                         struct rte_hash_bucket *bkt,
 884                         struct rte_hash_bucket *sec_bkt,
 885                         const struct rte_hash_key *key, void *data,
 886                         uint16_t sig, uint32_t bucket_idx,
 887                         uint32_t new_idx, int32_t *ret_val)
 888 {
 889         unsigned int i;
 890         struct queue_node queue[RTE_HASH_BFS_QUEUE_MAX_LEN];
 891         struct queue_node *tail, *head;
 892         struct rte_hash_bucket *curr_bkt, *alt_bkt;
 893         uint32_t cur_idx, alt_idx;
 894
 895         tail = queue;
 896         head = queue + 1;
 897         tail->bkt = bkt;
 898         tail->prev = NULL;
 899         tail->prev_slot = -1;
 900         tail->cur_bkt_idx = bucket_idx;
 901
 902         /* Cuckoo bfs Search */
 903         while (likely(tail != head && head <
 904                                         queue + RTE_HASH_BFS_QUEUE_MAX_LEN -
 905                                         RTE_HASH_BUCKET_ENTRIES)) {
 906                 curr_bkt = tail->bkt;
 907                 cur_idx = tail->cur_bkt_idx;
 908                 for (i = 0; i < RTE_HASH_BUCKET_ENTRIES; i++) {
 909                         if (curr_bkt->key_idx[i] == EMPTY_SLOT) {
 910                                 int32_t ret = rte_hash_cuckoo_move_insert_mw(h,
 911                                                 bkt, sec_bkt, key, data,
 912                                                 tail, i, sig,
 913                                                 new_idx, ret_val);
 914                                 if (likely(ret != -1))
 915                                         return ret;
 916                         }
 917
 918                         /* Enqueue new node and keep prev node info */
 919                         alt_idx = get_alt_bucket_index(h, cur_idx,
 920                                                 curr_bkt->sig_current[i]);
 921                         alt_bkt = &(h->buckets[alt_idx]);
 922                         head->bkt = alt_bkt;
 923                         head->cur_bkt_idx = alt_idx;
 924                         head->prev = tail;
 925                         head->prev_slot = i;
 926                         head++;
 927                 }
 928                 tail++;
 929         }
 930
 931         return -ENOSPC;
 932 }
 933
 934 static inline int32_t
 935 __rte_hash_add_key_with_hash(const struct rte_hash *h, const void *key,
 936                                                 hash_sig_t sig, void *data)
 937 {
 938         uint16_t short_sig;
 939         uint32_t prim_bucket_idx, sec_bucket_idx;
 940         struct rte_hash_bucket *prim_bkt, *sec_bkt, *cur_bkt;
 941         struct rte_hash_key *new_k, *keys = h->key_store;
 942         uint32_t slot_id;
 943         uint32_t ext_bkt_id;
 944         int ret;
 945         unsigned n_slots;
 946         unsigned lcore_id;
 947         unsigned int i;
 948         struct lcore_cache *cached_free_slots = NULL;
 949         int32_t ret_val;
 950         struct rte_hash_bucket *last;
 951
 952         short_sig = get_short_sig(sig);
 953         prim_bucket_idx = get_prim_bucket_index(h, sig);
 954         sec_bucket_idx = get_alt_bucket_index(h, prim_bucket_idx, short_sig);
 955         prim_bkt = &h->buckets[prim_bucket_idx];
 956         sec_bkt = &h->buckets[sec_bucket_idx];
 957         rte_prefetch0(prim_bkt);
 958         rte_prefetch0(sec_bkt);
 959
 960         /* Check if key is already inserted in primary location */
 961         __hash_rw_writer_lock(h);
 962         ret = search_and_update(h, data, key, prim_bkt, short_sig);
 963         if (ret != -1) {
 964                 __hash_rw_writer_unlock(h);
 965                 return ret;
 966         }
 967
 968         /* Check if key is already inserted in secondary location */
 969         FOR_EACH_BUCKET(cur_bkt, sec_bkt) {
 970                 ret = search_and_update(h, data, key, cur_bkt, short_sig);
 971                 if (ret != -1) {
 972                         __hash_rw_writer_unlock(h);
 973                         return ret;
 974                 }
 975         }
 976
 977         __hash_rw_writer_unlock(h);
 978
 979         /* Did not find a match, so get a new slot for storing the new key */
 980         if (h->use_local_cache) {
 981                 lcore_id = rte_lcore_id();
 982                 cached_free_slots = &h->local_free_slots[lcore_id];
 983                 /* Try to get a free slot from the local cache */
 984                 if (cached_free_slots->len == 0) {
 985                         /* Need to get another burst of free slots from global ring */
 986                         n_slots = rte_ring_mc_dequeue_burst_elem(h->free_slots,
 987                                         cached_free_slots->objs,
 988                                         sizeof(uint32_t),
 989                                         LCORE_CACHE_SIZE, NULL);
 990                         if (n_slots == 0) {
 991                                 return -ENOSPC;
 992                         }
 993
 994                         cached_free_slots->len += n_slots;
 995                 }
 996
 997                 /* Get a free slot from the local cache */
 998                 cached_free_slots->len--;
 999                 slot_id = cached_free_slots->objs[cached_free_slots->len];
1000         } else {
1001                 if (rte_ring_sc_dequeue_elem(h->free_slots, &slot_id,
1002                                                 sizeof(uint32_t)) != 0) {
1003                         return -ENOSPC;
1004                 }
1005         }
1006
1007         new_k = RTE_PTR_ADD(keys, slot_id * h->key_entry_size);
1008         /* The store to application data (by the application) at *data should
1009          * not leak after the store of pdata in the key store. i.e. pdata is
1010          * the guard variable. Release the application data to the readers.
1011          */
1012         __atomic_store_n(&new_k->pdata,
1013                 data,
1014                 __ATOMIC_RELEASE);
1015         /* Copy key */
1016         memcpy(new_k->key, key, h->key_len);
1017
1018         /* Find an empty slot and insert */
1019         ret = rte_hash_cuckoo_insert_mw(h, prim_bkt, sec_bkt, key, data,
1020                                         short_sig, slot_id, &ret_val);
1021         if (ret == 0)
1022                 return slot_id - 1;
1023         else if (ret == 1) {
1024                 enqueue_slot_back(h, cached_free_slots, slot_id);
1025                 return ret_val;
1026         }
1027
1028         /* Primary bucket full, need to make space for new entry */
1029         ret = rte_hash_cuckoo_make_space_mw(h, prim_bkt, sec_bkt, key, data,
1030                                 short_sig, prim_bucket_idx, slot_id, &ret_val);
1031         if (ret == 0)
1032                 return slot_id - 1;
1033         else if (ret == 1) {
1034                 enqueue_slot_back(h, cached_free_slots, slot_id);
1035                 return ret_val;
1036         }
1037
1038         /* Also search secondary bucket to get better occupancy */
1039         ret = rte_hash_cuckoo_make_space_mw(h, sec_bkt, prim_bkt, key, data,
1040                                 short_sig, sec_bucket_idx, slot_id, &ret_val);
1041
1042         if (ret == 0)
1043                 return slot_id - 1;
1044         else if (ret == 1) {
1045                 enqueue_slot_back(h, cached_free_slots, slot_id);
1046                 return ret_val;
1047         }
1048
1049         /* if ext table not enabled, we failed the insertion */
1050         if (!h->ext_table_support) {
1051                 enqueue_slot_back(h, cached_free_slots, slot_id);
1052                 return ret;
1053         }
1054
1055         /* Now we need to go through the extendable bucket. Protection is needed
1056          * to protect all extendable bucket processes.
1057          */
1058         __hash_rw_writer_lock(h);
1059         /* We check for duplicates again since could be inserted before the lock */
1060         ret = search_and_update(h, data, key, prim_bkt, short_sig);
1061         if (ret != -1) {
1062                 enqueue_slot_back(h, cached_free_slots, slot_id);
1063                 goto failure;
1064         }
1065
1066         FOR_EACH_BUCKET(cur_bkt, sec_bkt) {
1067                 ret = search_and_update(h, data, key, cur_bkt, short_sig);
1068                 if (ret != -1) {
1069                         enqueue_slot_back(h, cached_free_slots, slot_id);
1070                         goto failure;
1071                 }
1072         }
1073
1074         /* Search sec and ext buckets to find an empty entry to insert. */
1075         FOR_EACH_BUCKET(cur_bkt, sec_bkt) {
1076                 for (i = 0; i < RTE_HASH_BUCKET_ENTRIES; i++) {
1077                         /* Check if slot is available */
1078                         if (likely(cur_bkt->key_idx[i] == EMPTY_SLOT)) {
1079                                 cur_bkt->sig_current[i] = short_sig;
1080                                 /* Store to signature and key should not
1081                                  * leak after the store to key_idx. i.e.
1082                                  * key_idx is the guard variable for signature
1083                                  * and key.
1084                                  */
1085                                 __atomic_store_n(&cur_bkt->key_idx[i],
1086                                                  slot_id,
1087                                                  __ATOMIC_RELEASE);
1088                                 __hash_rw_writer_unlock(h);
1089                                 return slot_id - 1;
1090                         }
1091                 }
1092         }
1093
1094         /* Failed to get an empty entry from extendable buckets. Link a new
1095          * extendable bucket. We first get a free bucket from ring.
1096          */
1097         if (rte_ring_sc_dequeue_elem(h->free_ext_bkts, &ext_bkt_id,
1098                                                 sizeof(uint32_t)) != 0) {
1099                 ret = -ENOSPC;
1100                 goto failure;
1101         }
1102
1103         /* Use the first location of the new bucket */
1104         (h->buckets_ext[ext_bkt_id - 1]).sig_current[0] = short_sig;
1105         /* Store to signature and key should not leak after
1106          * the store to key_idx. i.e. key_idx is the guard variable
1107          * for signature and key.
1108          */
1109         __atomic_store_n(&(h->buckets_ext[ext_bkt_id - 1]).key_idx[0],
1110                          slot_id,
1111                          __ATOMIC_RELEASE);
1112         /* Link the new bucket to sec bucket linked list */
1113         last = rte_hash_get_last_bkt(sec_bkt);
1114         last->next = &h->buckets_ext[ext_bkt_id - 1];
1115         __hash_rw_writer_unlock(h);
1116         return slot_id - 1;
1117
1118 failure:
1119         __hash_rw_writer_unlock(h);
1120         return ret;
1121
1122 }
1123
1124 int32_t
1125 rte_hash_add_key_with_hash(const struct rte_hash *h,
1126                         const void *key, hash_sig_t sig)
1127 {
1128         RETURN_IF_TRUE(((h == NULL) || (key == NULL)), -EINVAL);
1129         return __rte_hash_add_key_with_hash(h, key, sig, 0);
1130 }
1131
1132 int32_t
1133 rte_hash_add_key(const struct rte_hash *h, const void *key)
1134 {
1135         RETURN_IF_TRUE(((h == NULL) || (key == NULL)), -EINVAL);
1136         return __rte_hash_add_key_with_hash(h, key, rte_hash_hash(h, key), 0);
1137 }
1138
1139 int
1140 rte_hash_add_key_with_hash_data(const struct rte_hash *h,
1141                         const void *key, hash_sig_t sig, void *data)
1142 {
1143         int ret;
1144
1145         RETURN_IF_TRUE(((h == NULL) || (key == NULL)), -EINVAL);
1146         ret = __rte_hash_add_key_with_hash(h, key, sig, data);
1147         if (ret >= 0)
1148                 return 0;
1149         else
1150                 return ret;
1151 }
1152
1153 int
1154 rte_hash_add_key_data(const struct rte_hash *h, const void *key, void *data)
1155 {
1156         int ret;
1157
1158         RETURN_IF_TRUE(((h == NULL) || (key == NULL)), -EINVAL);
1159
1160         ret = __rte_hash_add_key_with_hash(h, key, rte_hash_hash(h, key), data);
1161         if (ret >= 0)
1162                 return 0;
1163         else
1164                 return ret;
1165 }
1166
1167 /* Search one bucket to find the match key - uses rw lock */
1168 static inline int32_t
1169 search_one_bucket_l(const struct rte_hash *h, const void *key,
1170                 uint16_t sig, void **data,
1171                 const struct rte_hash_bucket *bkt)
1172 {
1173         int i;
1174         struct rte_hash_key *k, *keys = h->key_store;
1175
1176         for (i = 0; i < RTE_HASH_BUCKET_ENTRIES; i++) {
1177                 if (bkt->sig_current[i] == sig &&
1178                                 bkt->key_idx[i] != EMPTY_SLOT) {
1179                         k = (struct rte_hash_key *) ((char *)keys +
1180                                         bkt->key_idx[i] * h->key_entry_size);
1181
1182                         if (rte_hash_cmp_eq(key, k->key, h) == 0) {
1183                                 if (data != NULL)
1184                                         *data = k->pdata;
1185                                 /*
1186                                  * Return index where key is stored,
1187                                  * subtracting the first dummy index
1188                                  */
1189                                 return bkt->key_idx[i] - 1;
1190                         }
1191                 }
1192         }
1193         return -1;
1194 }
1195
1196 /* Search one bucket to find the match key */
1197 static inline int32_t
1198 search_one_bucket_lf(const struct rte_hash *h, const void *key, uint16_t sig,
1199                         void **data, const struct rte_hash_bucket *bkt)
1200 {
1201         int i;
1202         uint32_t key_idx;
1203         struct rte_hash_key *k, *keys = h->key_store;
1204
1205         for (i = 0; i < RTE_HASH_BUCKET_ENTRIES; i++) {
1206                 /* Signature comparison is done before the acquire-load
1207                  * of the key index to achieve better performance.
1208                  * This can result in the reader loading old signature
1209                  * (which matches), while the key_idx is updated to a
1210                  * value that belongs to a new key. However, the full
1211                  * key comparison will ensure that the lookup fails.
1212                  */
1213                 if (bkt->sig_current[i] == sig) {
1214                         key_idx = __atomic_load_n(&bkt->key_idx[i],
1215                                           __ATOMIC_ACQUIRE);
1216                         if (key_idx != EMPTY_SLOT) {
1217                                 k = (struct rte_hash_key *) ((char *)keys +
1218                                                 key_idx * h->key_entry_size);
1219
1220                                 if (rte_hash_cmp_eq(key, k->key, h) == 0) {
1221                                         if (data != NULL) {
1222                                                 *data = __atomic_load_n(
1223                                                         &k->pdata,
1224                                                         __ATOMIC_ACQUIRE);
1225                                         }
1226                                         /*
1227                                          * Return index where key is stored,
1228                                          * subtracting the first dummy index
1229                                          */
1230                                         return key_idx - 1;
1231                                 }
1232                         }
1233                 }
1234         }
1235         return -1;
1236 }
1237
1238 static inline int32_t
1239 __rte_hash_lookup_with_hash_l(const struct rte_hash *h, const void *key,
1240                                 hash_sig_t sig, void **data)
1241 {
1242         uint32_t prim_bucket_idx, sec_bucket_idx;
1243         struct rte_hash_bucket *bkt, *cur_bkt;
1244         int ret;
1245         uint16_t short_sig;
1246
1247         short_sig = get_short_sig(sig);
1248         prim_bucket_idx = get_prim_bucket_index(h, sig);
1249         sec_bucket_idx = get_alt_bucket_index(h, prim_bucket_idx, short_sig);
1250
1251         bkt = &h->buckets[prim_bucket_idx];
1252
1253         __hash_rw_reader_lock(h);
1254
1255         /* Check if key is in primary location */
1256         ret = search_one_bucket_l(h, key, short_sig, data, bkt);
1257         if (ret != -1) {
1258                 __hash_rw_reader_unlock(h);
1259                 return ret;
1260         }
1261         /* Calculate secondary hash */
1262         bkt = &h->buckets[sec_bucket_idx];
1263
1264         /* Check if key is in secondary location */
1265         FOR_EACH_BUCKET(cur_bkt, bkt) {
1266                 ret = search_one_bucket_l(h, key, short_sig,
1267                                         data, cur_bkt);
1268                 if (ret != -1) {
1269                         __hash_rw_reader_unlock(h);
1270                         return ret;
1271                 }
1272         }
1273
1274         __hash_rw_reader_unlock(h);
1275
1276         return -ENOENT;
1277 }
1278
1279 static inline int32_t
1280 __rte_hash_lookup_with_hash_lf(const struct rte_hash *h, const void *key,
1281                                         hash_sig_t sig, void **data)
1282 {
1283         uint32_t prim_bucket_idx, sec_bucket_idx;
1284         struct rte_hash_bucket *bkt, *cur_bkt;
1285         uint32_t cnt_b, cnt_a;
1286         int ret;
1287         uint16_t short_sig;
1288
1289         short_sig = get_short_sig(sig);
1290         prim_bucket_idx = get_prim_bucket_index(h, sig);
1291         sec_bucket_idx = get_alt_bucket_index(h, prim_bucket_idx, short_sig);
1292
1293         do {
1294                 /* Load the table change counter before the lookup
1295                  * starts. Acquire semantics will make sure that
1296                  * loads in search_one_bucket are not hoisted.
1297                  */
1298                 cnt_b = __atomic_load_n(h->tbl_chng_cnt,
1299                                 __ATOMIC_ACQUIRE);
1300
1301                 /* Check if key is in primary location */
1302                 bkt = &h->buckets[prim_bucket_idx];
1303                 ret = search_one_bucket_lf(h, key, short_sig, data, bkt);
1304                 if (ret != -1)
1305                         return ret;
1306                 /* Calculate secondary hash */
1307                 bkt = &h->buckets[sec_bucket_idx];
1308
1309                 /* Check if key is in secondary location */
1310                 FOR_EACH_BUCKET(cur_bkt, bkt) {
1311                         ret = search_one_bucket_lf(h, key, short_sig,
1312                                                 data, cur_bkt);
1313                         if (ret != -1)
1314                                 return ret;
1315                 }
1316
1317                 /* The loads of sig_current in search_one_bucket
1318                  * should not move below the load from tbl_chng_cnt.
1319                  */
1320                 __atomic_thread_fence(__ATOMIC_ACQUIRE);
1321                 /* Re-read the table change counter to check if the
1322                  * table has changed during search. If yes, re-do
1323                  * the search.
1324                  * This load should not get hoisted. The load
1325                  * acquires on cnt_b, key index in primary bucket
1326                  * and key index in secondary bucket will make sure
1327                  * that it does not get hoisted.
1328                  */
1329                 cnt_a = __atomic_load_n(h->tbl_chng_cnt,
1330                                         __ATOMIC_ACQUIRE);
1331         } while (cnt_b != cnt_a);
1332
1333         return -ENOENT;
1334 }
1335
1336 static inline int32_t
1337 __rte_hash_lookup_with_hash(const struct rte_hash *h, const void *key,
1338                                         hash_sig_t sig, void **data)
1339 {
1340         if (h->readwrite_concur_lf_support)
1341                 return __rte_hash_lookup_with_hash_lf(h, key, sig, data);
1342         else
1343                 return __rte_hash_lookup_with_hash_l(h, key, sig, data);
1344 }
1345
1346 int32_t
1347 rte_hash_lookup_with_hash(const struct rte_hash *h,
1348                         const void *key, hash_sig_t sig)
1349 {
1350         RETURN_IF_TRUE(((h == NULL) || (key == NULL)), -EINVAL);
1351         return __rte_hash_lookup_with_hash(h, key, sig, NULL);
1352 }
1353
1354 int32_t
1355 rte_hash_lookup(const struct rte_hash *h, const void *key)
1356 {
1357         RETURN_IF_TRUE(((h == NULL) || (key == NULL)), -EINVAL);
1358         return __rte_hash_lookup_with_hash(h, key, rte_hash_hash(h, key), NULL);
1359 }
1360
1361 int
1362 rte_hash_lookup_with_hash_data(const struct rte_hash *h,
1363                         const void *key, hash_sig_t sig, void **data)
1364 {
1365         RETURN_IF_TRUE(((h == NULL) || (key == NULL)), -EINVAL);
1366         return __rte_hash_lookup_with_hash(h, key, sig, data);
1367 }
1368
1369 int
1370 rte_hash_lookup_data(const struct rte_hash *h, const void *key, void **data)
1371 {
1372         RETURN_IF_TRUE(((h == NULL) || (key == NULL)), -EINVAL);
1373         return __rte_hash_lookup_with_hash(h, key, rte_hash_hash(h, key), data);
1374 }
1375
1376 static inline void
1377 remove_entry(const struct rte_hash *h, struct rte_hash_bucket *bkt, unsigned i)
1378 {
1379         unsigned lcore_id, n_slots;
1380         struct lcore_cache *cached_free_slots;
1381
1382         if (h->use_local_cache) {
1383                 lcore_id = rte_lcore_id();
1384                 cached_free_slots = &h->local_free_slots[lcore_id];
1385                 /* Cache full, need to free it. */
1386                 if (cached_free_slots->len == LCORE_CACHE_SIZE) {
1387                         /* Need to enqueue the free slots in global ring. */
1388                         n_slots = rte_ring_mp_enqueue_burst_elem(h->free_slots,
1389                                                 cached_free_slots->objs,
1390                                                 sizeof(uint32_t),
1391                                                 LCORE_CACHE_SIZE, NULL);
1392                         ERR_IF_TRUE((n_slots == 0),
1393                                 "%s: could not enqueue free slots in global ring\n",
1394                                 __func__);
1395                         cached_free_slots->len -= n_slots;
1396                 }
1397                 /* Put index of new free slot in cache. */
1398                 cached_free_slots->objs[cached_free_slots->len] =
1399                                                         bkt->key_idx[i];
1400                 cached_free_slots->len++;
1401         } else {
1402                 rte_ring_sp_enqueue_elem(h->free_slots,
1403                                 &bkt->key_idx[i], sizeof(uint32_t));
1404         }
1405 }
1406
1407 /* Compact the linked list by moving key from last entry in linked list to the
1408  * empty slot.
1409  */
1410 static inline void
1411 __rte_hash_compact_ll(const struct rte_hash *h,
1412                         struct rte_hash_bucket *cur_bkt, int pos) {
1413         int i;
1414         struct rte_hash_bucket *last_bkt;
1415
1416         if (!cur_bkt->next)
1417                 return;
1418
1419         last_bkt = rte_hash_get_last_bkt(cur_bkt);
1420
1421         for (i = RTE_HASH_BUCKET_ENTRIES - 1; i >= 0; i--) {
1422                 if (last_bkt->key_idx[i] != EMPTY_SLOT) {
1423                         cur_bkt->sig_current[pos] = last_bkt->sig_current[i];
1424                         __atomic_store_n(&cur_bkt->key_idx[pos],
1425                                          last_bkt->key_idx[i],
1426                                          __ATOMIC_RELEASE);
1427                         if (h->readwrite_concur_lf_support) {
1428                                 /* Inform the readers that the table has changed
1429                                  * Since there is one writer, load acquire on
1430                                  * tbl_chng_cnt is not required.
1431                                  */
1432                                 __atomic_store_n(h->tbl_chng_cnt,
1433                                          *h->tbl_chng_cnt + 1,
1434                                          __ATOMIC_RELEASE);
1435                                 /* The store to sig_current should
1436                                  * not move above the store to tbl_chng_cnt.
1437                                  */
1438                                 __atomic_thread_fence(__ATOMIC_RELEASE);
1439                         }
1440                         last_bkt->sig_current[i] = NULL_SIGNATURE;
1441                         __atomic_store_n(&last_bkt->key_idx[i],
1442                                          EMPTY_SLOT,
1443                                          __ATOMIC_RELEASE);
1444                         return;
1445                 }
1446         }
1447 }
1448
1449 /* Search one bucket and remove the matched key.
1450  * Writer is expected to hold the lock while calling this
1451  * function.
1452  */
1453 static inline int32_t
1454 search_and_remove(const struct rte_hash *h, const void *key,
1455                         struct rte_hash_bucket *bkt, uint16_t sig, int *pos)
1456 {
1457         struct rte_hash_key *k, *keys = h->key_store;
1458         unsigned int i;
1459         uint32_t key_idx;
1460
1461         /* Check if key is in bucket */
1462         for (i = 0; i < RTE_HASH_BUCKET_ENTRIES; i++) {
1463                 key_idx = __atomic_load_n(&bkt->key_idx[i],
1464                                           __ATOMIC_ACQUIRE);
1465                 if (bkt->sig_current[i] == sig && key_idx != EMPTY_SLOT) {
1466                         k = (struct rte_hash_key *) ((char *)keys +
1467                                         key_idx * h->key_entry_size);
1468                         if (rte_hash_cmp_eq(key, k->key, h) == 0) {
1469                                 bkt->sig_current[i] = NULL_SIGNATURE;
1470                                 /* Free the key store index if
1471                                  * no_free_on_del is disabled.
1472                                  */
1473                                 if (!h->no_free_on_del)
1474                                         remove_entry(h, bkt, i);
1475
1476                                 __atomic_store_n(&bkt->key_idx[i],
1477                                                  EMPTY_SLOT,
1478                                                  __ATOMIC_RELEASE);
1479
1480                                 *pos = i;
1481                                 /*
1482                                  * Return index where key is stored,
1483                                  * subtracting the first dummy index
1484                                  */
1485                                 return key_idx - 1;
1486                         }
1487                 }
1488         }
1489         return -1;
1490 }
1491
1492 static inline int32_t
1493 __rte_hash_del_key_with_hash(const struct rte_hash *h, const void *key,
1494                                                 hash_sig_t sig)
1495 {
1496         uint32_t prim_bucket_idx, sec_bucket_idx;
1497         struct rte_hash_bucket *prim_bkt, *sec_bkt, *prev_bkt, *last_bkt;
1498         struct rte_hash_bucket *cur_bkt;
1499         int pos;
1500         int32_t ret, i;
1501         uint16_t short_sig;
1502
1503         short_sig = get_short_sig(sig);
1504         prim_bucket_idx = get_prim_bucket_index(h, sig);
1505         sec_bucket_idx = get_alt_bucket_index(h, prim_bucket_idx, short_sig);
1506         prim_bkt = &h->buckets[prim_bucket_idx];
1507
1508         __hash_rw_writer_lock(h);
1509         /* look for key in primary bucket */
1510         ret = search_and_remove(h, key, prim_bkt, short_sig, &pos);
1511         if (ret != -1) {
1512                 __rte_hash_compact_ll(h, prim_bkt, pos);
1513                 last_bkt = prim_bkt->next;
1514                 prev_bkt = prim_bkt;
1515                 goto return_bkt;
1516         }
1517
1518         /* Calculate secondary hash */
1519         sec_bkt = &h->buckets[sec_bucket_idx];
1520
1521         FOR_EACH_BUCKET(cur_bkt, sec_bkt) {
1522                 ret = search_and_remove(h, key, cur_bkt, short_sig, &pos);
1523                 if (ret != -1) {
1524                         __rte_hash_compact_ll(h, cur_bkt, pos);
1525                         last_bkt = sec_bkt->next;
1526                         prev_bkt = sec_bkt;
1527                         goto return_bkt;
1528                 }
1529         }
1530
1531         __hash_rw_writer_unlock(h);
1532         return -ENOENT;
1533
1534 /* Search last bucket to see if empty to be recycled */
1535 return_bkt:
1536         if (!last_bkt) {
1537                 __hash_rw_writer_unlock(h);
1538                 return ret;
1539         }
1540         while (last_bkt->next) {
1541                 prev_bkt = last_bkt;
1542                 last_bkt = last_bkt->next;
1543         }
1544
1545         for (i = 0; i < RTE_HASH_BUCKET_ENTRIES; i++) {
1546                 if (last_bkt->key_idx[i] != EMPTY_SLOT)
1547                         break;
1548         }
1549         /* found empty bucket and recycle */
1550         if (i == RTE_HASH_BUCKET_ENTRIES) {
1551                 prev_bkt->next = NULL;
1552                 uint32_t index = last_bkt - h->buckets_ext + 1;
1553                 /* Recycle the empty bkt if
1554                  * no_free_on_del is disabled.
1555                  */
1556                 if (h->no_free_on_del)
1557                         /* Store index of an empty ext bkt to be recycled
1558                          * on calling rte_hash_del_xxx APIs.
1559                          * When lock free read-write concurrency is enabled,
1560                          * an empty ext bkt cannot be put into free list
1561                          * immediately (as readers might be using it still).
1562                          * Hence freeing of the ext bkt is piggy-backed to
1563                          * freeing of the key index.
1564                          */
1565                         h->ext_bkt_to_free[ret] = index;
1566                 else
1567                         rte_ring_sp_enqueue_elem(h->free_ext_bkts, &index,
1568                                                         sizeof(uint32_t));
1569         }
1570         __hash_rw_writer_unlock(h);
1571         return ret;
1572 }
1573
1574 int32_t
1575 rte_hash_del_key_with_hash(const struct rte_hash *h,
1576                         const void *key, hash_sig_t sig)
1577 {
1578         RETURN_IF_TRUE(((h == NULL) || (key == NULL)), -EINVAL);
1579         return __rte_hash_del_key_with_hash(h, key, sig);
1580 }
1581
1582 int32_t
1583 rte_hash_del_key(const struct rte_hash *h, const void *key)
1584 {
1585         RETURN_IF_TRUE(((h == NULL) || (key == NULL)), -EINVAL);
1586         return __rte_hash_del_key_with_hash(h, key, rte_hash_hash(h, key));
1587 }
1588
1589 int
1590 rte_hash_get_key_with_position(const struct rte_hash *h, const int32_t position,
1591                                void **key)
1592 {
1593         RETURN_IF_TRUE(((h == NULL) || (key == NULL)), -EINVAL);
1594
1595         struct rte_hash_key *k, *keys = h->key_store;
1596         k = (struct rte_hash_key *) ((char *) keys + (position + 1) *
1597                                      h->key_entry_size);
1598         *key = k->key;
1599
1600         if (position !=
1601             __rte_hash_lookup_with_hash(h, *key, rte_hash_hash(h, *key),
1602                                         NULL)) {
1603                 return -ENOENT;
1604         }
1605
1606         return 0;
1607 }
1608
1609 int
1610 rte_hash_free_key_with_position(const struct rte_hash *h,
1611                                 const int32_t position)
1612 {
1613         /* Key index where key is stored, adding the first dummy index */
1614         uint32_t key_idx = position + 1;
1615
1616         RETURN_IF_TRUE(((h == NULL) || (key_idx == EMPTY_SLOT)), -EINVAL);
1617
1618         unsigned int lcore_id, n_slots;
1619         struct lcore_cache *cached_free_slots;
1620         const uint32_t total_entries = h->use_local_cache ?
1621                 h->entries + (RTE_MAX_LCORE - 1) * (LCORE_CACHE_SIZE - 1) + 1
1622                                                         : h->entries + 1;
1623
1624         /* Out of bounds */
1625         if (key_idx >= total_entries)
1626                 return -EINVAL;
1627         if (h->ext_table_support && h->readwrite_concur_lf_support) {
1628                 uint32_t index = h->ext_bkt_to_free[position];
1629                 if (index) {
1630                         /* Recycle empty ext bkt to free list. */
1631                         rte_ring_sp_enqueue_elem(h->free_ext_bkts, &index,
1632                                                         sizeof(uint32_t));
1633                         h->ext_bkt_to_free[position] = 0;
1634                 }
1635         }
1636
1637         if (h->use_local_cache) {
1638                 lcore_id = rte_lcore_id();
1639                 cached_free_slots = &h->local_free_slots[lcore_id];
1640                 /* Cache full, need to free it. */
1641                 if (cached_free_slots->len == LCORE_CACHE_SIZE) {
1642                         /* Need to enqueue the free slots in global ring. */
1643                         n_slots = rte_ring_mp_enqueue_burst_elem(h->free_slots,
1644                                                 cached_free_slots->objs,
1645                                                 sizeof(uint32_t),
1646                                                 LCORE_CACHE_SIZE, NULL);
1647                         RETURN_IF_TRUE((n_slots == 0), -EFAULT);
1648                         cached_free_slots->len -= n_slots;
1649                 }
1650                 /* Put index of new free slot in cache. */
1651                 cached_free_slots->objs[cached_free_slots->len] = key_idx;
1652                 cached_free_slots->len++;
1653         } else {
1654                 rte_ring_sp_enqueue_elem(h->free_slots, &key_idx,
1655                                                 sizeof(uint32_t));
1656         }
1657
1658         return 0;
1659 }
1660
1661 static inline void
1662 compare_signatures(uint32_t *prim_hash_matches, uint32_t *sec_hash_matches,
1663                         const struct rte_hash_bucket *prim_bkt,
1664                         const struct rte_hash_bucket *sec_bkt,
1665                         uint16_t sig,
1666                         enum rte_hash_sig_compare_function sig_cmp_fn)
1667 {
1668         unsigned int i;
1669
1670         /* For match mask the first bit of every two bits indicates the match */
1671         switch (sig_cmp_fn) {
1672 #if defined(RTE_MACHINE_CPUFLAG_SSE2)
1673         case RTE_HASH_COMPARE_SSE:
1674                 /* Compare all signatures in the bucket */
1675                 *prim_hash_matches = _mm_movemask_epi8(_mm_cmpeq_epi16(
1676                                 _mm_load_si128(
1677                                         (__m128i const *)prim_bkt->sig_current),
1678                                 _mm_set1_epi16(sig)));
1679                 /* Compare all signatures in the bucket */
1680                 *sec_hash_matches = _mm_movemask_epi8(_mm_cmpeq_epi16(
1681                                 _mm_load_si128(
1682                                         (__m128i const *)sec_bkt->sig_current),
1683                                 _mm_set1_epi16(sig)));
1684                 break;
1685 #elif defined(RTE_MACHINE_CPUFLAG_NEON)
1686         case RTE_HASH_COMPARE_NEON: {
1687                 uint16x8_t vmat, vsig, x;
1688                 int16x8_t shift = {-15, -13, -11, -9, -7, -5, -3, -1};
1689
1690                 vsig = vld1q_dup_u16((uint16_t const *)&sig);
1691                 /* Compare all signatures in the primary bucket */
1692                 vmat = vceqq_u16(vsig,
1693                         vld1q_u16((uint16_t const *)prim_bkt->sig_current));
1694                 x = vshlq_u16(vandq_u16(vmat, vdupq_n_u16(0x8000)), shift);
1695                 *prim_hash_matches = (uint32_t)(vaddvq_u16(x));
1696                 /* Compare all signatures in the secondary bucket */
1697                 vmat = vceqq_u16(vsig,
1698                         vld1q_u16((uint16_t const *)sec_bkt->sig_current));
1699                 x = vshlq_u16(vandq_u16(vmat, vdupq_n_u16(0x8000)), shift);
1700                 *sec_hash_matches = (uint32_t)(vaddvq_u16(x));
1701                 }
1702                 break;
1703 #endif
1704         default:
1705                 for (i = 0; i < RTE_HASH_BUCKET_ENTRIES; i++) {
1706                         *prim_hash_matches |=
1707                                 ((sig == prim_bkt->sig_current[i]) << (i << 1));
1708                         *sec_hash_matches |=
1709                                 ((sig == sec_bkt->sig_current[i]) << (i << 1));
1710                 }
1711         }
1712 }
1713
1714 static inline void
1715 __bulk_lookup_l(const struct rte_hash *h, const void **keys,
1716                 const struct rte_hash_bucket **primary_bkt,
1717                 const struct rte_hash_bucket **secondary_bkt,
1718                 uint16_t *sig, int32_t num_keys, int32_t *positions,
1719                 uint64_t *hit_mask, void *data[])
1720 {
1721         uint64_t hits = 0;
1722         int32_t i;
1723         int32_t ret;
1724         uint32_t prim_hitmask[RTE_HASH_LOOKUP_BULK_MAX] = {0};
1725         uint32_t sec_hitmask[RTE_HASH_LOOKUP_BULK_MAX] = {0};
1726         struct rte_hash_bucket *cur_bkt, *next_bkt;
1727
1728         __hash_rw_reader_lock(h);
1729
1730         /* Compare signatures and prefetch key slot of first hit */
1731         for (i = 0; i < num_keys; i++) {
1732                 compare_signatures(&prim_hitmask[i], &sec_hitmask[i],
1733                         primary_bkt[i], secondary_bkt[i],
1734                         sig[i], h->sig_cmp_fn);
1735
1736                 if (prim_hitmask[i]) {
1737                         uint32_t first_hit =
1738                                         __builtin_ctzl(prim_hitmask[i])
1739                                         >> 1;
1740                         uint32_t key_idx =
1741                                 primary_bkt[i]->key_idx[first_hit];
1742                         const struct rte_hash_key *key_slot =
1743                                 (const struct rte_hash_key *)(
1744                                 (const char *)h->key_store +
1745                                 key_idx * h->key_entry_size);
1746                         rte_prefetch0(key_slot);
1747                         continue;
1748                 }
1749
1750                 if (sec_hitmask[i]) {
1751                         uint32_t first_hit =
1752                                         __builtin_ctzl(sec_hitmask[i])
1753                                         >> 1;
1754                         uint32_t key_idx =
1755                                 secondary_bkt[i]->key_idx[first_hit];
1756                         const struct rte_hash_key *key_slot =
1757                                 (const struct rte_hash_key *)(
1758                                 (const char *)h->key_store +
1759                                 key_idx * h->key_entry_size);
1760                         rte_prefetch0(key_slot);
1761                 }
1762         }
1763
1764         /* Compare keys, first hits in primary first */
1765         for (i = 0; i < num_keys; i++) {
1766                 positions[i] = -ENOENT;
1767                 while (prim_hitmask[i]) {
1768                         uint32_t hit_index =
1769                                         __builtin_ctzl(prim_hitmask[i])
1770                                         >> 1;
1771                         uint32_t key_idx =
1772                                 primary_bkt[i]->key_idx[hit_index];
1773                         const struct rte_hash_key *key_slot =
1774                                 (const struct rte_hash_key *)(
1775                                 (const char *)h->key_store +
1776                                 key_idx * h->key_entry_size);
1777
1778                         /*
1779                          * If key index is 0, do not compare key,
1780                          * as it is checking the dummy slot
1781                          */
1782                         if (!!key_idx &
1783                                 !rte_hash_cmp_eq(
1784                                         key_slot->key, keys[i], h)) {
1785                                 if (data != NULL)
1786                                         data[i] = key_slot->pdata;
1787
1788                                 hits |= 1ULL << i;
1789                                 positions[i] = key_idx - 1;
1790                                 goto next_key;
1791                         }
1792                         prim_hitmask[i] &= ~(3ULL << (hit_index << 1));
1793                 }
1794
1795                 while (sec_hitmask[i]) {
1796                         uint32_t hit_index =
1797                                         __builtin_ctzl(sec_hitmask[i])
1798                                         >> 1;
1799                         uint32_t key_idx =
1800                                 secondary_bkt[i]->key_idx[hit_index];
1801                         const struct rte_hash_key *key_slot =
1802                                 (const struct rte_hash_key *)(
1803                                 (const char *)h->key_store +
1804                                 key_idx * h->key_entry_size);
1805
1806                         /*
1807                          * If key index is 0, do not compare key,
1808                          * as it is checking the dummy slot
1809                          */
1810
1811                         if (!!key_idx &
1812                                 !rte_hash_cmp_eq(
1813                                         key_slot->key, keys[i], h)) {
1814                                 if (data != NULL)
1815                                         data[i] = key_slot->pdata;
1816
1817                                 hits |= 1ULL << i;
1818                                 positions[i] = key_idx - 1;
1819                                 goto next_key;
1820                         }
1821                         sec_hitmask[i] &= ~(3ULL << (hit_index << 1));
1822                 }
1823 next_key:
1824                 continue;
1825         }
1826
1827         /* all found, do not need to go through ext bkt */
1828         if ((hits == ((1ULL << num_keys) - 1)) || !h->ext_table_support) {
1829                 if (hit_mask != NULL)
1830                         *hit_mask = hits;
1831                 __hash_rw_reader_unlock(h);
1832                 return;
1833         }
1834
1835         /* need to check ext buckets for match */
1836         for (i = 0; i < num_keys; i++) {
1837                 if ((hits & (1ULL << i)) != 0)
1838                         continue;
1839                 next_bkt = secondary_bkt[i]->next;
1840                 FOR_EACH_BUCKET(cur_bkt, next_bkt) {
1841                         if (data != NULL)
1842                                 ret = search_one_bucket_l(h, keys[i],
1843                                                 sig[i], &data[i], cur_bkt);
1844                         else
1845                                 ret = search_one_bucket_l(h, keys[i],
1846                                                 sig[i], NULL, cur_bkt);
1847                         if (ret != -1) {
1848                                 positions[i] = ret;
1849                                 hits |= 1ULL << i;
1850                                 break;
1851                         }
1852                 }
1853         }
1854
1855         __hash_rw_reader_unlock(h);
1856
1857         if (hit_mask != NULL)
1858                 *hit_mask = hits;
1859 }
1860
1861 static inline void
1862 __bulk_lookup_lf(const struct rte_hash *h, const void **keys,
1863                 const struct rte_hash_bucket **primary_bkt,
1864                 const struct rte_hash_bucket **secondary_bkt,
1865                 uint16_t *sig, int32_t num_keys, int32_t *positions,
1866                 uint64_t *hit_mask, void *data[])
1867 {
1868         uint64_t hits = 0;
1869         int32_t i;
1870         int32_t ret;
1871         uint32_t prim_hitmask[RTE_HASH_LOOKUP_BULK_MAX] = {0};
1872         uint32_t sec_hitmask[RTE_HASH_LOOKUP_BULK_MAX] = {0};
1873         struct rte_hash_bucket *cur_bkt, *next_bkt;
1874         uint32_t cnt_b, cnt_a;
1875
1876         for (i = 0; i < num_keys; i++)
1877                 positions[i] = -ENOENT;
1878
1879         do {
1880                 /* Load the table change counter before the lookup
1881                  * starts. Acquire semantics will make sure that
1882                  * loads in compare_signatures are not hoisted.
1883                  */
1884                 cnt_b = __atomic_load_n(h->tbl_chng_cnt,
1885                                         __ATOMIC_ACQUIRE);
1886
1887                 /* Compare signatures and prefetch key slot of first hit */
1888                 for (i = 0; i < num_keys; i++) {
1889                         compare_signatures(&prim_hitmask[i], &sec_hitmask[i],
1890                                 primary_bkt[i], secondary_bkt[i],
1891                                 sig[i], h->sig_cmp_fn);
1892
1893                         if (prim_hitmask[i]) {
1894                                 uint32_t first_hit =
1895                                                 __builtin_ctzl(prim_hitmask[i])
1896                                                 >> 1;
1897                                 uint32_t key_idx =
1898                                         primary_bkt[i]->key_idx[first_hit];
1899                                 const struct rte_hash_key *key_slot =
1900                                         (const struct rte_hash_key *)(
1901                                         (const char *)h->key_store +
1902                                         key_idx * h->key_entry_size);
1903                                 rte_prefetch0(key_slot);
1904                                 continue;
1905                         }
1906
1907                         if (sec_hitmask[i]) {
1908                                 uint32_t first_hit =
1909                                                 __builtin_ctzl(sec_hitmask[i])
1910                                                 >> 1;
1911                                 uint32_t key_idx =
1912                                         secondary_bkt[i]->key_idx[first_hit];
1913                                 const struct rte_hash_key *key_slot =
1914                                         (const struct rte_hash_key *)(
1915                                         (const char *)h->key_store +
1916                                         key_idx * h->key_entry_size);
1917                                 rte_prefetch0(key_slot);
1918                         }
1919                 }
1920
1921                 /* Compare keys, first hits in primary first */
1922                 for (i = 0; i < num_keys; i++) {
1923                         while (prim_hitmask[i]) {
1924                                 uint32_t hit_index =
1925                                                 __builtin_ctzl(prim_hitmask[i])
1926                                                 >> 1;
1927                                 uint32_t key_idx =
1928                                 __atomic_load_n(
1929                                         &primary_bkt[i]->key_idx[hit_index],
1930                                         __ATOMIC_ACQUIRE);
1931                                 const struct rte_hash_key *key_slot =
1932                                         (const struct rte_hash_key *)(
1933                                         (const char *)h->key_store +
1934                                         key_idx * h->key_entry_size);
1935
1936                                 /*
1937                                  * If key index is 0, do not compare key,
1938                                  * as it is checking the dummy slot
1939                                  */
1940                                 if (!!key_idx &
1941                                         !rte_hash_cmp_eq(
1942                                                 key_slot->key, keys[i], h)) {
1943                                         if (data != NULL)
1944                                                 data[i] = __atomic_load_n(
1945                                                         &key_slot->pdata,
1946                                                         __ATOMIC_ACQUIRE);
1947
1948                                         hits |= 1ULL << i;
1949                                         positions[i] = key_idx - 1;
1950                                         goto next_key;
1951                                 }
1952                                 prim_hitmask[i] &= ~(3ULL << (hit_index << 1));
1953                         }
1954
1955                         while (sec_hitmask[i]) {
1956                                 uint32_t hit_index =
1957                                                 __builtin_ctzl(sec_hitmask[i])
1958                                                 >> 1;
1959                                 uint32_t key_idx =
1960                                 __atomic_load_n(
1961                                         &secondary_bkt[i]->key_idx[hit_index],
1962                                         __ATOMIC_ACQUIRE);
1963                                 const struct rte_hash_key *key_slot =
1964                                         (const struct rte_hash_key *)(
1965                                         (const char *)h->key_store +
1966                                         key_idx * h->key_entry_size);
1967
1968                                 /*
1969                                  * If key index is 0, do not compare key,
1970                                  * as it is checking the dummy slot
1971                                  */
1972
1973                                 if (!!key_idx &
1974                                         !rte_hash_cmp_eq(
1975                                                 key_slot->key, keys[i], h)) {
1976                                         if (data != NULL)
1977                                                 data[i] = __atomic_load_n(
1978                                                         &key_slot->pdata,
1979                                                         __ATOMIC_ACQUIRE);
1980
1981                                         hits |= 1ULL << i;
1982                                         positions[i] = key_idx - 1;
1983                                         goto next_key;
1984                                 }
1985                                 sec_hitmask[i] &= ~(3ULL << (hit_index << 1));
1986                         }
1987 next_key:
1988                         continue;
1989                 }
1990
1991                 /* all found, do not need to go through ext bkt */
1992                 if (hits == ((1ULL << num_keys) - 1)) {
1993                         if (hit_mask != NULL)
1994                                 *hit_mask = hits;
1995                         return;
1996                 }
1997                 /* need to check ext buckets for match */
1998                 if (h->ext_table_support) {
1999                         for (i = 0; i < num_keys; i++) {
2000                                 if ((hits & (1ULL << i)) != 0)
2001                                         continue;
2002                                 next_bkt = secondary_bkt[i]->next;
2003                                 FOR_EACH_BUCKET(cur_bkt, next_bkt) {
2004                                         if (data != NULL)
2005                                                 ret = search_one_bucket_lf(h,
2006                                                         keys[i], sig[i],
2007                                                         &data[i], cur_bkt);
2008                                         else
2009                                                 ret = search_one_bucket_lf(h,
2010                                                                 keys[i], sig[i],
2011                                                                 NULL, cur_bkt);
2012                                         if (ret != -1) {
2013                                                 positions[i] = ret;
2014                                                 hits |= 1ULL << i;
2015                                                 break;
2016                                         }
2017                                 }
2018                         }
2019                 }
2020                 /* The loads of sig_current in compare_signatures
2021                  * should not move below the load from tbl_chng_cnt.
2022                  */
2023                 __atomic_thread_fence(__ATOMIC_ACQUIRE);
2024                 /* Re-read the table change counter to check if the
2025                  * table has changed during search. If yes, re-do
2026                  * the search.
2027                  * This load should not get hoisted. The load
2028                  * acquires on cnt_b, primary key index and secondary
2029                  * key index will make sure that it does not get
2030                  * hoisted.
2031                  */
2032                 cnt_a = __atomic_load_n(h->tbl_chng_cnt,
2033                                         __ATOMIC_ACQUIRE);
2034         } while (cnt_b != cnt_a);
2035
2036         if (hit_mask != NULL)
2037                 *hit_mask = hits;
2038 }
2039
2040 #define PREFETCH_OFFSET 4
2041 static inline void
2042 __bulk_lookup_prefetching_loop(const struct rte_hash *h,
2043         const void **keys, int32_t num_keys,
2044         uint16_t *sig,
2045         const struct rte_hash_bucket **primary_bkt,
2046         const struct rte_hash_bucket **secondary_bkt)
2047 {
2048         int32_t i;
2049         uint32_t prim_hash[RTE_HASH_LOOKUP_BULK_MAX];
2050         uint32_t prim_index[RTE_HASH_LOOKUP_BULK_MAX];
2051         uint32_t sec_index[RTE_HASH_LOOKUP_BULK_MAX];
2052
2053         /* Prefetch first keys */
2054         for (i = 0; i < PREFETCH_OFFSET && i < num_keys; i++)
2055                 rte_prefetch0(keys[i]);
2056
2057         /*
2058          * Prefetch rest of the keys, calculate primary and
2059          * secondary bucket and prefetch them
2060          */
2061         for (i = 0; i < (num_keys - PREFETCH_OFFSET); i++) {
2062                 rte_prefetch0(keys[i + PREFETCH_OFFSET]);
2063
2064                 prim_hash[i] = rte_hash_hash(h, keys[i]);
2065
2066                 sig[i] = get_short_sig(prim_hash[i]);
2067                 prim_index[i] = get_prim_bucket_index(h, prim_hash[i]);
2068                 sec_index[i] = get_alt_bucket_index(h, prim_index[i], sig[i]);
2069
2070                 primary_bkt[i] = &h->buckets[prim_index[i]];
2071                 secondary_bkt[i] = &h->buckets[sec_index[i]];
2072
2073                 rte_prefetch0(primary_bkt[i]);
2074                 rte_prefetch0(secondary_bkt[i]);
2075         }
2076
2077         /* Calculate and prefetch rest of the buckets */
2078         for (; i < num_keys; i++) {
2079                 prim_hash[i] = rte_hash_hash(h, keys[i]);
2080
2081                 sig[i] = get_short_sig(prim_hash[i]);
2082                 prim_index[i] = get_prim_bucket_index(h, prim_hash[i]);
2083                 sec_index[i] = get_alt_bucket_index(h, prim_index[i], sig[i]);
2084
2085                 primary_bkt[i] = &h->buckets[prim_index[i]];
2086                 secondary_bkt[i] = &h->buckets[sec_index[i]];
2087
2088                 rte_prefetch0(primary_bkt[i]);
2089                 rte_prefetch0(secondary_bkt[i]);
2090         }
2091 }
2092
2093
2094 static inline void
2095 __rte_hash_lookup_bulk_l(const struct rte_hash *h, const void **keys,
2096                         int32_t num_keys, int32_t *positions,
2097                         uint64_t *hit_mask, void *data[])
2098 {
2099         uint16_t sig[RTE_HASH_LOOKUP_BULK_MAX];
2100         const struct rte_hash_bucket *primary_bkt[RTE_HASH_LOOKUP_BULK_MAX];
2101         const struct rte_hash_bucket *secondary_bkt[RTE_HASH_LOOKUP_BULK_MAX];
2102
2103         __bulk_lookup_prefetching_loop(h, keys, num_keys, sig,
2104                 primary_bkt, secondary_bkt);
2105
2106         __bulk_lookup_l(h, keys, primary_bkt, secondary_bkt, sig, num_keys,
2107                 positions, hit_mask, data);
2108 }
2109
2110 static inline void
2111 __rte_hash_lookup_bulk_lf(const struct rte_hash *h, const void **keys,
2112                         int32_t num_keys, int32_t *positions,
2113                         uint64_t *hit_mask, void *data[])
2114 {
2115         uint16_t sig[RTE_HASH_LOOKUP_BULK_MAX];
2116         const struct rte_hash_bucket *primary_bkt[RTE_HASH_LOOKUP_BULK_MAX];
2117         const struct rte_hash_bucket *secondary_bkt[RTE_HASH_LOOKUP_BULK_MAX];
2118
2119         __bulk_lookup_prefetching_loop(h, keys, num_keys, sig,
2120                 primary_bkt, secondary_bkt);
2121
2122         __bulk_lookup_lf(h, keys, primary_bkt, secondary_bkt, sig, num_keys,
2123                 positions, hit_mask, data);
2124 }
2125
2126 static inline void
2127 __rte_hash_lookup_bulk(const struct rte_hash *h, const void **keys,
2128                         int32_t num_keys, int32_t *positions,
2129                         uint64_t *hit_mask, void *data[])
2130 {
2131         if (h->readwrite_concur_lf_support)
2132                 __rte_hash_lookup_bulk_lf(h, keys, num_keys, positions,
2133                                           hit_mask, data);
2134         else
2135                 __rte_hash_lookup_bulk_l(h, keys, num_keys, positions,
2136                                          hit_mask, data);
2137 }
2138
2139 int
2140 rte_hash_lookup_bulk(const struct rte_hash *h, const void **keys,
2141                       uint32_t num_keys, int32_t *positions)
2142 {
2143         RETURN_IF_TRUE(((h == NULL) || (keys == NULL) || (num_keys == 0) ||
2144                         (num_keys > RTE_HASH_LOOKUP_BULK_MAX) ||
2145                         (positions == NULL)), -EINVAL);
2146
2147         __rte_hash_lookup_bulk(h, keys, num_keys, positions, NULL, NULL);
2148         return 0;
2149 }
2150
2151 int
2152 rte_hash_lookup_bulk_data(const struct rte_hash *h, const void **keys,
2153                       uint32_t num_keys, uint64_t *hit_mask, void *data[])
2154 {
2155         RETURN_IF_TRUE(((h == NULL) || (keys == NULL) || (num_keys == 0) ||
2156                         (num_keys > RTE_HASH_LOOKUP_BULK_MAX) ||
2157                         (hit_mask == NULL)), -EINVAL);
2158
2159         int32_t positions[num_keys];
2160
2161         __rte_hash_lookup_bulk(h, keys, num_keys, positions, hit_mask, data);
2162
2163         /* Return number of hits */
2164         return __builtin_popcountl(*hit_mask);
2165 }
2166
2167
2168 static inline void
2169 __rte_hash_lookup_with_hash_bulk_l(const struct rte_hash *h,
2170                         const void **keys, hash_sig_t *prim_hash,
2171                         int32_t num_keys, int32_t *positions,
2172                         uint64_t *hit_mask, void *data[])
2173 {
2174         int32_t i;
2175         uint32_t prim_index[RTE_HASH_LOOKUP_BULK_MAX];
2176         uint32_t sec_index[RTE_HASH_LOOKUP_BULK_MAX];
2177         uint16_t sig[RTE_HASH_LOOKUP_BULK_MAX];
2178         const struct rte_hash_bucket *primary_bkt[RTE_HASH_LOOKUP_BULK_MAX];
2179         const struct rte_hash_bucket *secondary_bkt[RTE_HASH_LOOKUP_BULK_MAX];
2180
2181         /*
2182          * Prefetch keys, calculate primary and
2183          * secondary bucket and prefetch them
2184          */
2185         for (i = 0; i < num_keys; i++) {
2186                 rte_prefetch0(keys[i]);
2187
2188                 sig[i] = get_short_sig(prim_hash[i]);
2189                 prim_index[i] = get_prim_bucket_index(h, prim_hash[i]);
2190                 sec_index[i] = get_alt_bucket_index(h, prim_index[i], sig[i]);
2191
2192                 primary_bkt[i] = &h->buckets[prim_index[i]];
2193                 secondary_bkt[i] = &h->buckets[sec_index[i]];
2194
2195                 rte_prefetch0(primary_bkt[i]);
2196                 rte_prefetch0(secondary_bkt[i]);
2197         }
2198
2199         __bulk_lookup_l(h, keys, primary_bkt, secondary_bkt, sig, num_keys,
2200                 positions, hit_mask, data);
2201 }
2202
2203 static inline void
2204 __rte_hash_lookup_with_hash_bulk_lf(const struct rte_hash *h,
2205                         const void **keys, hash_sig_t *prim_hash,
2206                         int32_t num_keys, int32_t *positions,
2207                         uint64_t *hit_mask, void *data[])
2208 {
2209         int32_t i;
2210         uint32_t prim_index[RTE_HASH_LOOKUP_BULK_MAX];
2211         uint32_t sec_index[RTE_HASH_LOOKUP_BULK_MAX];
2212         uint16_t sig[RTE_HASH_LOOKUP_BULK_MAX];
2213         const struct rte_hash_bucket *primary_bkt[RTE_HASH_LOOKUP_BULK_MAX];
2214         const struct rte_hash_bucket *secondary_bkt[RTE_HASH_LOOKUP_BULK_MAX];
2215
2216         /*
2217          * Prefetch keys, calculate primary and
2218          * secondary bucket and prefetch them
2219          */
2220         for (i = 0; i < num_keys; i++) {
2221                 rte_prefetch0(keys[i]);
2222
2223                 sig[i] = get_short_sig(prim_hash[i]);
2224                 prim_index[i] = get_prim_bucket_index(h, prim_hash[i]);
2225                 sec_index[i] = get_alt_bucket_index(h, prim_index[i], sig[i]);
2226
2227                 primary_bkt[i] = &h->buckets[prim_index[i]];
2228                 secondary_bkt[i] = &h->buckets[sec_index[i]];
2229
2230                 rte_prefetch0(primary_bkt[i]);
2231                 rte_prefetch0(secondary_bkt[i]);
2232         }
2233
2234         __bulk_lookup_lf(h, keys, primary_bkt, secondary_bkt, sig, num_keys,
2235                 positions, hit_mask, data);
2236 }
2237
2238 static inline void
2239 __rte_hash_lookup_with_hash_bulk(const struct rte_hash *h, const void **keys,
2240                         hash_sig_t *prim_hash, int32_t num_keys,
2241                         int32_t *positions, uint64_t *hit_mask, void *data[])
2242 {
2243         if (h->readwrite_concur_lf_support)
2244                 __rte_hash_lookup_with_hash_bulk_lf(h, keys, prim_hash,
2245                                 num_keys, positions, hit_mask, data);
2246         else
2247                 __rte_hash_lookup_with_hash_bulk_l(h, keys, prim_hash,
2248                                 num_keys, positions, hit_mask, data);
2249 }
2250
2251 int
2252 rte_hash_lookup_with_hash_bulk(const struct rte_hash *h, const void **keys,
2253                 hash_sig_t *sig, uint32_t num_keys, int32_t *positions)
2254 {
2255         RETURN_IF_TRUE(((h == NULL) || (keys == NULL) ||
2256                         (sig == NULL) || (num_keys == 0) ||
2257                         (num_keys > RTE_HASH_LOOKUP_BULK_MAX) ||
2258                         (positions == NULL)), -EINVAL);
2259
2260         __rte_hash_lookup_with_hash_bulk(h, keys, sig, num_keys,
2261                 positions, NULL, NULL);
2262         return 0;
2263 }
2264
2265 int
2266 rte_hash_lookup_with_hash_bulk_data(const struct rte_hash *h,
2267                 const void **keys, hash_sig_t *sig,
2268                 uint32_t num_keys, uint64_t *hit_mask, void *data[])
2269 {
2270         RETURN_IF_TRUE(((h == NULL) || (keys == NULL) ||
2271                         (sig == NULL) || (num_keys == 0) ||
2272                         (num_keys > RTE_HASH_LOOKUP_BULK_MAX) ||
2273                         (hit_mask == NULL)), -EINVAL);
2274
2275         int32_t positions[num_keys];
2276
2277         __rte_hash_lookup_with_hash_bulk(h, keys, sig, num_keys,
2278                         positions, hit_mask, data);
2279
2280         /* Return number of hits */
2281         return __builtin_popcountl(*hit_mask);
2282 }
2283
2284 int32_t
2285 rte_hash_iterate(const struct rte_hash *h, const void **key, void **data, uint32_t *next)
2286 {
2287         uint32_t bucket_idx, idx, position;
2288         struct rte_hash_key *next_key;
2289
2290         RETURN_IF_TRUE(((h == NULL) || (next == NULL)), -EINVAL);
2291
2292         const uint32_t total_entries_main = h->num_buckets *
2293                                                         RTE_HASH_BUCKET_ENTRIES;
2294         const uint32_t total_entries = total_entries_main << 1;
2295
2296         /* Out of bounds of all buckets (both main table and ext table) */
2297         if (*next >= total_entries_main)
2298                 goto extend_table;
2299
2300         /* Calculate bucket and index of current iterator */
2301         bucket_idx = *next / RTE_HASH_BUCKET_ENTRIES;
2302         idx = *next % RTE_HASH_BUCKET_ENTRIES;
2303
2304         /* If current position is empty, go to the next one */
2305         while ((position = __atomic_load_n(&h->buckets[bucket_idx].key_idx[idx],
2306                                         __ATOMIC_ACQUIRE)) == EMPTY_SLOT) {
2307                 (*next)++;
2308                 /* End of table */
2309                 if (*next == total_entries_main)
2310                         goto extend_table;
2311                 bucket_idx = *next / RTE_HASH_BUCKET_ENTRIES;
2312                 idx = *next % RTE_HASH_BUCKET_ENTRIES;
2313         }
2314
2315         __hash_rw_reader_lock(h);
2316         next_key = (struct rte_hash_key *) ((char *)h->key_store +
2317                                 position * h->key_entry_size);
2318         /* Return key and data */
2319         *key = next_key->key;
2320         *data = next_key->pdata;
2321
2322         __hash_rw_reader_unlock(h);
2323
2324         /* Increment iterator */
2325         (*next)++;
2326
2327         return position - 1;
2328
2329 /* Begin to iterate extendable buckets */
2330 extend_table:
2331         /* Out of total bound or if ext bucket feature is not enabled */
2332         if (*next >= total_entries || !h->ext_table_support)
2333                 return -ENOENT;
2334
2335         bucket_idx = (*next - total_entries_main) / RTE_HASH_BUCKET_ENTRIES;
2336         idx = (*next - total_entries_main) % RTE_HASH_BUCKET_ENTRIES;
2337
2338         while ((position = h->buckets_ext[bucket_idx].key_idx[idx]) == EMPTY_SLOT) {
2339                 (*next)++;
2340                 if (*next == total_entries)
2341                         return -ENOENT;
2342                 bucket_idx = (*next - total_entries_main) /
2343                                                 RTE_HASH_BUCKET_ENTRIES;
2344                 idx = (*next - total_entries_main) % RTE_HASH_BUCKET_ENTRIES;
2345         }
2346         __hash_rw_reader_lock(h);
2347         next_key = (struct rte_hash_key *) ((char *)h->key_store +
2348                                 position * h->key_entry_size);
2349         /* Return key and data */
2350         *key = next_key->key;
2351         *data = next_key->pdata;
2352
2353         __hash_rw_reader_unlock(h);
2354
2355         /* Increment iterator */
2356         (*next)++;
2357         return position - 1;
2358 }