hash: use partial-key hashing
[dpdk.git] / lib / librte_hash / rte_cuckoo_hash.c
index 375e7d2..9a48934 100644 (file)
 #include "rte_hash.h"
 #include "rte_cuckoo_hash.h"
 
-#if defined(RTE_ARCH_X86)
-#include "rte_cuckoo_hash_x86.h"
-#endif
+#define FOR_EACH_BUCKET(CURRENT_BKT, START_BUCKET)                            \
+       for (CURRENT_BKT = START_BUCKET;                                      \
+               CURRENT_BKT != NULL;                                          \
+               CURRENT_BKT = CURRENT_BKT->next)
 
 TAILQ_HEAD(rte_hash_list, rte_tailq_entry);
 
@@ -66,6 +67,14 @@ rte_hash_find_existing(const char *name)
        return h;
 }
 
+static inline struct rte_hash_bucket *
+rte_hash_get_last_bkt(struct rte_hash_bucket *lst_bkt)
+{
+       while (lst_bkt->next != NULL)
+               lst_bkt = lst_bkt->next;
+       return lst_bkt;
+}
+
 void rte_hash_set_cmp_func(struct rte_hash *h, rte_hash_cmp_eq_t func)
 {
        h->cmp_jump_table_idx = KEY_CUSTOM;
@@ -81,6 +90,36 @@ rte_hash_cmp_eq(const void *key1, const void *key2, const struct rte_hash *h)
                return cmp_jump_table[h->cmp_jump_table_idx](key1, key2, h->key_len);
 }
 
+/*
+ * We use higher 16 bits of hash as the signature value stored in table.
+ * We use the lower bits for the primary bucket
+ * location. Then we XOR primary bucket location and the signature
+ * to get the secondary bucket location. This is same as
+ * proposed in Bin Fan, et al's paper
+ * "MemC3: Compact and Concurrent MemCache with Dumber Caching and
+ * Smarter Hashing". The benefit to use
+ * XOR is that one could derive the alternative bucket location
+ * by only using the current bucket location and the signature.
+ */
+static inline uint16_t
+get_short_sig(const hash_sig_t hash)
+{
+       return hash >> 16;
+}
+
+static inline uint32_t
+get_prim_bucket_index(const struct rte_hash *h, const hash_sig_t hash)
+{
+       return hash & h->bucket_bitmask;
+}
+
+static inline uint32_t
+get_alt_bucket_index(const struct rte_hash *h,
+                       uint32_t cur_bkt_idx, uint16_t sig)
+{
+       return (cur_bkt_idx ^ sig) & h->bucket_bitmask;
+}
+
 struct rte_hash *
 rte_hash_create(const struct rte_hash_parameters *params)
 {
@@ -88,13 +127,19 @@ rte_hash_create(const struct rte_hash_parameters *params)
        struct rte_tailq_entry *te = NULL;
        struct rte_hash_list *hash_list;
        struct rte_ring *r = NULL;
+       struct rte_ring *r_ext = NULL;
        char hash_name[RTE_HASH_NAMESIZE];
        void *k = NULL;
        void *buckets = NULL;
+       void *buckets_ext = NULL;
        char ring_name[RTE_RING_NAMESIZE];
+       char ext_ring_name[RTE_RING_NAMESIZE];
        unsigned num_key_slots;
-       unsigned hw_trans_mem_support = 0;
        unsigned i;
+       unsigned int hw_trans_mem_support = 0, multi_writer_support = 0;
+       unsigned int ext_table_support = 0;
+       unsigned int readwrite_concur_support = 0;
+
        rte_hash_function default_hash_func = (rte_hash_function)rte_jhash;
 
        hash_list = RTE_TAILQ_CAST(rte_hash_tailq.head, rte_hash_list);
@@ -117,27 +162,56 @@ rte_hash_create(const struct rte_hash_parameters *params)
        if (params->extra_flag & RTE_HASH_EXTRA_FLAGS_TRANS_MEM_SUPPORT)
                hw_trans_mem_support = 1;
 
+       if (params->extra_flag & RTE_HASH_EXTRA_FLAGS_MULTI_WRITER_ADD)
+               multi_writer_support = 1;
+
+       if (params->extra_flag & RTE_HASH_EXTRA_FLAGS_RW_CONCURRENCY) {
+               readwrite_concur_support = 1;
+               multi_writer_support = 1;
+       }
+
+       if (params->extra_flag & RTE_HASH_EXTRA_FLAGS_EXT_TABLE)
+               ext_table_support = 1;
+
        /* Store all keys and leave the first entry as a dummy entry for lookup_bulk */
-       if (hw_trans_mem_support)
+       if (multi_writer_support)
                /*
                 * Increase number of slots by total number of indices
                 * that can be stored in the lcore caches
                 * except for the first cache
                 */
                num_key_slots = params->entries + (RTE_MAX_LCORE - 1) *
-                                       LCORE_CACHE_SIZE + 1;
+                                       (LCORE_CACHE_SIZE - 1) + 1;
        else
                num_key_slots = params->entries + 1;
 
        snprintf(ring_name, sizeof(ring_name), "HT_%s", params->name);
        /* Create ring (Dummy slot index is not enqueued) */
-       r = rte_ring_create(ring_name, rte_align32pow2(num_key_slots - 1),
+       r = rte_ring_create(ring_name, rte_align32pow2(num_key_slots),
                        params->socket_id, 0);
        if (r == NULL) {
                RTE_LOG(ERR, HASH, "memory allocation failed\n");
                goto err;
        }
 
+       const uint32_t num_buckets = rte_align32pow2(params->entries) /
+                                               RTE_HASH_BUCKET_ENTRIES;
+
+       /* Create ring for extendable buckets. */
+       if (ext_table_support) {
+               snprintf(ext_ring_name, sizeof(ext_ring_name), "HT_EXT_%s",
+                                                               params->name);
+               r_ext = rte_ring_create(ext_ring_name,
+                               rte_align32pow2(num_buckets + 1),
+                               params->socket_id, 0);
+
+               if (r_ext == NULL) {
+                       RTE_LOG(ERR, HASH, "ext buckets memory allocation "
+                                                               "failed\n");
+                       goto err;
+               }
+       }
+
        snprintf(hash_name, sizeof(hash_name), "HT_%s", params->name);
 
        rte_rwlock_write_lock(RTE_EAL_TAILQ_RWLOCK);
@@ -170,18 +244,34 @@ rte_hash_create(const struct rte_hash_parameters *params)
                goto err_unlock;
        }
 
-       const uint32_t num_buckets = rte_align32pow2(params->entries)
-                                       / RTE_HASH_BUCKET_ENTRIES;
-
        buckets = rte_zmalloc_socket(NULL,
                                num_buckets * sizeof(struct rte_hash_bucket),
                                RTE_CACHE_LINE_SIZE, params->socket_id);
 
        if (buckets == NULL) {
-               RTE_LOG(ERR, HASH, "memory allocation failed\n");
+               RTE_LOG(ERR, HASH, "buckets memory allocation failed\n");
                goto err_unlock;
        }
 
+       /* Allocate same number of extendable buckets */
+       if (ext_table_support) {
+               buckets_ext = rte_zmalloc_socket(NULL,
+                               num_buckets * sizeof(struct rte_hash_bucket),
+                               RTE_CACHE_LINE_SIZE, params->socket_id);
+               if (buckets_ext == NULL) {
+                       RTE_LOG(ERR, HASH, "ext buckets memory allocation "
+                                                       "failed\n");
+                       goto err_unlock;
+               }
+               /* Populate ext bkt ring. We reserve 0 similar to the
+                * key-data slot, just in case in future we want to
+                * use bucket index for the linked list and 0 means NULL
+                * for next bucket
+                */
+               for (i = 1; i <= num_buckets; i++)
+                       rte_ring_sp_enqueue(r_ext, (void *)((uintptr_t) i));
+       }
+
        const uint32_t key_entry_size = sizeof(struct rte_hash_key) + params->key_len;
        const uint64_t key_tbl_size = (uint64_t) key_entry_size * num_key_slots;
 
@@ -232,7 +322,7 @@ rte_hash_create(const struct rte_hash_parameters *params)
        h->cmp_jump_table_idx = KEY_OTHER_BYTES;
 #endif
 
-       if (hw_trans_mem_support) {
+       if (multi_writer_support) {
                h->local_free_slots = rte_zmalloc_socket(NULL,
                                sizeof(struct lcore_cache) * RTE_MAX_LCORE,
                                RTE_CACHE_LINE_SIZE, params->socket_id);
@@ -255,39 +345,38 @@ rte_hash_create(const struct rte_hash_parameters *params)
        h->num_buckets = num_buckets;
        h->bucket_bitmask = h->num_buckets - 1;
        h->buckets = buckets;
+       h->buckets_ext = buckets_ext;
+       h->free_ext_bkts = r_ext;
        h->hash_func = (params->hash_func == NULL) ?
                default_hash_func : params->hash_func;
        h->key_store = k;
        h->free_slots = r;
        h->hw_trans_mem_support = hw_trans_mem_support;
+       h->multi_writer_support = multi_writer_support;
+       h->readwrite_concur_support = readwrite_concur_support;
+       h->ext_table_support = ext_table_support;
 
 #if defined(RTE_ARCH_X86)
-       if (rte_cpu_get_flag_enabled(RTE_CPUFLAG_AVX2))
-               h->sig_cmp_fn = RTE_HASH_COMPARE_AVX2;
-       else if (rte_cpu_get_flag_enabled(RTE_CPUFLAG_SSE2))
+       if (rte_cpu_get_flag_enabled(RTE_CPUFLAG_SSE2))
                h->sig_cmp_fn = RTE_HASH_COMPARE_SSE;
        else
 #endif
                h->sig_cmp_fn = RTE_HASH_COMPARE_SCALAR;
 
-       /* Turn on multi-writer only with explicit flat from user and TM
+       /* Turn on multi-writer only with explicit flag from user and TM
         * support.
         */
-       if (params->extra_flag & RTE_HASH_EXTRA_FLAGS_MULTI_WRITER_ADD) {
-               if (h->hw_trans_mem_support) {
-                       h->add_key = ADD_KEY_MULTIWRITER_TM;
-               } else {
-                       h->add_key = ADD_KEY_MULTIWRITER;
-                       h->multiwriter_lock = rte_malloc(NULL,
-                                                       sizeof(rte_spinlock_t),
-                                                       LCORE_CACHE_SIZE);
-                       rte_spinlock_init(h->multiwriter_lock);
-               }
-       } else
-               h->add_key = ADD_KEY_SINGLEWRITER;
+       if (h->multi_writer_support) {
+               h->readwrite_lock = rte_malloc(NULL, sizeof(rte_rwlock_t),
+                                               RTE_CACHE_LINE_SIZE);
+               if (h->readwrite_lock == NULL)
+                       goto err_unlock;
+
+               rte_rwlock_init(h->readwrite_lock);
+       }
 
        /* Populate free slots ring. Entry zero is reserved for key misses. */
-       for (i = 1; i < params->entries + 1; i++)
+       for (i = 1; i < num_key_slots; i++)
                rte_ring_sp_enqueue(r, (void *)((uintptr_t) i));
 
        te->data = (void *) h;
@@ -299,9 +388,11 @@ err_unlock:
        rte_rwlock_write_unlock(RTE_EAL_TAILQ_RWLOCK);
 err:
        rte_ring_free(r);
+       rte_ring_free(r_ext);
        rte_free(te);
        rte_free(h);
        rte_free(buckets);
+       rte_free(buckets_ext);
        rte_free(k);
        return NULL;
 }
@@ -334,14 +425,15 @@ rte_hash_free(struct rte_hash *h)
 
        rte_rwlock_write_unlock(RTE_EAL_TAILQ_RWLOCK);
 
-       if (h->hw_trans_mem_support)
+       if (h->multi_writer_support) {
                rte_free(h->local_free_slots);
-
-       if (h->add_key == ADD_KEY_MULTIWRITER)
-               rte_free(h->multiwriter_lock);
+               rte_free(h->readwrite_lock);
+       }
        rte_ring_free(h->free_slots);
+       rte_ring_free(h->free_ext_bkts);
        rte_free(h->key_store);
        rte_free(h->buckets);
+       rte_free(h->buckets_ext);
        rte_free(h);
        rte_free(te);
 }
@@ -353,27 +445,77 @@ rte_hash_hash(const struct rte_hash *h, const void *key)
        return h->hash_func(key, h->key_len, h->hash_func_init_val);
 }
 
-/* Calc the secondary hash value from the primary hash value of a given key */
-static inline hash_sig_t
-rte_hash_secondary_hash(const hash_sig_t primary_hash)
+int32_t
+rte_hash_count(const struct rte_hash *h)
 {
-       static const unsigned all_bits_shift = 12;
-       static const unsigned alt_bits_xor = 0x5bd1e995;
+       uint32_t tot_ring_cnt, cached_cnt = 0;
+       uint32_t i, ret;
 
-       uint32_t tag = primary_hash >> all_bits_shift;
+       if (h == NULL)
+               return -EINVAL;
 
-       return primary_hash ^ ((tag + 1) * alt_bits_xor);
+       if (h->multi_writer_support) {
+               tot_ring_cnt = h->entries + (RTE_MAX_LCORE - 1) *
+                                       (LCORE_CACHE_SIZE - 1);
+               for (i = 0; i < RTE_MAX_LCORE; i++)
+                       cached_cnt += h->local_free_slots[i].len;
+
+               ret = tot_ring_cnt - rte_ring_count(h->free_slots) -
+                                                               cached_cnt;
+       } else {
+               tot_ring_cnt = h->entries;
+               ret = tot_ring_cnt - rte_ring_count(h->free_slots);
+       }
+       return ret;
+}
+
+/* Read write locks implemented using rte_rwlock */
+static inline void
+__hash_rw_writer_lock(const struct rte_hash *h)
+{
+       if (h->multi_writer_support && h->hw_trans_mem_support)
+               rte_rwlock_write_lock_tm(h->readwrite_lock);
+       else if (h->multi_writer_support)
+               rte_rwlock_write_lock(h->readwrite_lock);
+}
+
+static inline void
+__hash_rw_reader_lock(const struct rte_hash *h)
+{
+       if (h->readwrite_concur_support && h->hw_trans_mem_support)
+               rte_rwlock_read_lock_tm(h->readwrite_lock);
+       else if (h->readwrite_concur_support)
+               rte_rwlock_read_lock(h->readwrite_lock);
+}
+
+static inline void
+__hash_rw_writer_unlock(const struct rte_hash *h)
+{
+       if (h->multi_writer_support && h->hw_trans_mem_support)
+               rte_rwlock_write_unlock_tm(h->readwrite_lock);
+       else if (h->multi_writer_support)
+               rte_rwlock_write_unlock(h->readwrite_lock);
+}
+
+static inline void
+__hash_rw_reader_unlock(const struct rte_hash *h)
+{
+       if (h->readwrite_concur_support && h->hw_trans_mem_support)
+               rte_rwlock_read_unlock_tm(h->readwrite_lock);
+       else if (h->readwrite_concur_support)
+               rte_rwlock_read_unlock(h->readwrite_lock);
 }
 
 void
 rte_hash_reset(struct rte_hash *h)
 {
        void *ptr;
-       unsigned i;
+       uint32_t tot_ring_cnt, i;
 
        if (h == NULL)
                return;
 
+       __hash_rw_writer_lock(h);
        memset(h->buckets, 0, h->num_buckets * sizeof(struct rte_hash_bucket));
        memset(h->key_store, 0, h->key_entry_size * (h->entries + 1));
 
@@ -381,131 +523,332 @@ rte_hash_reset(struct rte_hash *h)
        while (rte_ring_dequeue(h->free_slots, &ptr) == 0)
                rte_pause();
 
+       /* clear free extendable bucket ring and memory */
+       if (h->ext_table_support) {
+               memset(h->buckets_ext, 0, h->num_buckets *
+                                               sizeof(struct rte_hash_bucket));
+               while (rte_ring_dequeue(h->free_ext_bkts, &ptr) == 0)
+                       rte_pause();
+       }
+
        /* Repopulate the free slots ring. Entry zero is reserved for key misses */
-       for (i = 1; i < h->entries + 1; i++)
+       if (h->multi_writer_support)
+               tot_ring_cnt = h->entries + (RTE_MAX_LCORE - 1) *
+                                       (LCORE_CACHE_SIZE - 1);
+       else
+               tot_ring_cnt = h->entries;
+
+       for (i = 1; i < tot_ring_cnt + 1; i++)
                rte_ring_sp_enqueue(h->free_slots, (void *)((uintptr_t) i));
 
-       if (h->hw_trans_mem_support) {
+       /* Repopulate the free ext bkt ring. */
+       if (h->ext_table_support) {
+               for (i = 1; i <= h->num_buckets; i++)
+                       rte_ring_sp_enqueue(h->free_ext_bkts,
+                                               (void *)((uintptr_t) i));
+       }
+
+       if (h->multi_writer_support) {
                /* Reset local caches per lcore */
                for (i = 0; i < RTE_MAX_LCORE; i++)
                        h->local_free_slots[i].len = 0;
        }
+       __hash_rw_writer_unlock(h);
 }
 
-/* Search for an entry that can be pushed to its alternative location */
-static inline int
-make_space_bucket(const struct rte_hash *h, struct rte_hash_bucket *bkt,
-               unsigned int *nr_pushes)
+/*
+ * Function called to enqueue back an index in the cache/ring,
+ * as slot has not being used and it can be used in the
+ * next addition attempt.
+ */
+static inline void
+enqueue_slot_back(const struct rte_hash *h,
+               struct lcore_cache *cached_free_slots,
+               void *slot_id)
 {
-       unsigned i, j;
-       int ret;
-       uint32_t next_bucket_idx;
-       struct rte_hash_bucket *next_bkt[RTE_HASH_BUCKET_ENTRIES];
+       if (h->multi_writer_support) {
+               cached_free_slots->objs[cached_free_slots->len] = slot_id;
+               cached_free_slots->len++;
+       } else
+               rte_ring_sp_enqueue(h->free_slots, slot_id);
+}
+
+/* Search a key from bucket and update its data */
+static inline int32_t
+search_and_update(const struct rte_hash *h, void *data, const void *key,
+       struct rte_hash_bucket *bkt, uint16_t sig)
+{
+       int i;
+       struct rte_hash_key *k, *keys = h->key_store;
 
-       /*
-        * Push existing item (search for bucket with space in
-        * alternative locations) to its alternative location
-        */
        for (i = 0; i < RTE_HASH_BUCKET_ENTRIES; i++) {
-               /* Search for space in alternative locations */
-               next_bucket_idx = bkt->sig_alt[i] & h->bucket_bitmask;
-               next_bkt[i] = &h->buckets[next_bucket_idx];
-               for (j = 0; j < RTE_HASH_BUCKET_ENTRIES; j++) {
-                       if (next_bkt[i]->key_idx[j] == EMPTY_SLOT)
-                               break;
+               if (bkt->sig_current[i] == sig) {
+                       k = (struct rte_hash_key *) ((char *)keys +
+                                       bkt->key_idx[i] * h->key_entry_size);
+                       if (rte_hash_cmp_eq(key, k->key, h) == 0) {
+                               /* Update data */
+                               k->pdata = data;
+                               /*
+                                * Return index where key is stored,
+                                * subtracting the first dummy index
+                                */
+                               return bkt->key_idx[i] - 1;
+                       }
                }
+       }
+       return -1;
+}
 
-               if (j != RTE_HASH_BUCKET_ENTRIES)
-                       break;
+/* Only tries to insert at one bucket (@prim_bkt) without trying to push
+ * buckets around.
+ * return 1 if matching existing key, return 0 if succeeds, return -1 for no
+ * empty entry.
+ */
+static inline int32_t
+rte_hash_cuckoo_insert_mw(const struct rte_hash *h,
+               struct rte_hash_bucket *prim_bkt,
+               struct rte_hash_bucket *sec_bkt,
+               const struct rte_hash_key *key, void *data,
+               uint16_t sig, uint32_t new_idx,
+               int32_t *ret_val)
+{
+       unsigned int i;
+       struct rte_hash_bucket *cur_bkt;
+       int32_t ret;
+
+       __hash_rw_writer_lock(h);
+       /* Check if key was inserted after last check but before this
+        * protected region in case of inserting duplicated keys.
+        */
+       ret = search_and_update(h, data, key, prim_bkt, sig);
+       if (ret != -1) {
+               __hash_rw_writer_unlock(h);
+               *ret_val = ret;
+               return 1;
        }
 
-       /* Alternative location has spare room (end of recursive function) */
-       if (i != RTE_HASH_BUCKET_ENTRIES) {
-               next_bkt[i]->sig_alt[j] = bkt->sig_current[i];
-               next_bkt[i]->sig_current[j] = bkt->sig_alt[i];
-               next_bkt[i]->key_idx[j] = bkt->key_idx[i];
-               return i;
+       FOR_EACH_BUCKET(cur_bkt, sec_bkt) {
+               ret = search_and_update(h, data, key, cur_bkt, sig);
+               if (ret != -1) {
+                       __hash_rw_writer_unlock(h);
+                       *ret_val = ret;
+                       return 1;
+               }
        }
 
-       /* Pick entry that has not been pushed yet */
-       for (i = 0; i < RTE_HASH_BUCKET_ENTRIES; i++)
-               if (bkt->flag[i] == 0)
+       /* Insert new entry if there is room in the primary
+        * bucket.
+        */
+       for (i = 0; i < RTE_HASH_BUCKET_ENTRIES; i++) {
+               /* Check if slot is available */
+               if (likely(prim_bkt->key_idx[i] == EMPTY_SLOT)) {
+                       prim_bkt->sig_current[i] = sig;
+                       prim_bkt->key_idx[i] = new_idx;
                        break;
+               }
+       }
+       __hash_rw_writer_unlock(h);
 
-       /* All entries have been pushed, so entry cannot be added */
-       if (i == RTE_HASH_BUCKET_ENTRIES || ++(*nr_pushes) > RTE_HASH_MAX_PUSHES)
-               return -ENOSPC;
+       if (i != RTE_HASH_BUCKET_ENTRIES)
+               return 0;
 
-       /* Set flag to indicate that this entry is going to be pushed */
-       bkt->flag[i] = 1;
+       /* no empty entry */
+       return -1;
+}
 
-       /* Need room in alternative bucket to insert the pushed entry */
-       ret = make_space_bucket(h, next_bkt[i], nr_pushes);
-       /*
-        * After recursive function.
-        * Clear flags and insert the pushed entry
-        * in its alternative location if successful,
-        * or return error
+/* Shift buckets along provided cuckoo_path (@leaf and @leaf_slot) and fill
+ * the path head with new entry (sig, alt_hash, new_idx)
+ * return 1 if matched key found, return -1 if cuckoo path invalided and fail,
+ * return 0 if succeeds.
+ */
+static inline int
+rte_hash_cuckoo_move_insert_mw(const struct rte_hash *h,
+                       struct rte_hash_bucket *bkt,
+                       struct rte_hash_bucket *alt_bkt,
+                       const struct rte_hash_key *key, void *data,
+                       struct queue_node *leaf, uint32_t leaf_slot,
+                       uint16_t sig, uint32_t new_idx,
+                       int32_t *ret_val)
+{
+       uint32_t prev_alt_bkt_idx;
+       struct rte_hash_bucket *cur_bkt;
+       struct queue_node *prev_node, *curr_node = leaf;
+       struct rte_hash_bucket *prev_bkt, *curr_bkt = leaf->bkt;
+       uint32_t prev_slot, curr_slot = leaf_slot;
+       int32_t ret;
+
+       __hash_rw_writer_lock(h);
+
+       /* In case empty slot was gone before entering protected region */
+       if (curr_bkt->key_idx[curr_slot] != EMPTY_SLOT) {
+               __hash_rw_writer_unlock(h);
+               return -1;
+       }
+
+       /* Check if key was inserted after last check but before this
+        * protected region.
         */
-       bkt->flag[i] = 0;
-       if (ret >= 0) {
-               next_bkt[i]->sig_alt[ret] = bkt->sig_current[i];
-               next_bkt[i]->sig_current[ret] = bkt->sig_alt[i];
-               next_bkt[i]->key_idx[ret] = bkt->key_idx[i];
-               return i;
-       } else
-               return ret;
+       ret = search_and_update(h, data, key, bkt, sig);
+       if (ret != -1) {
+               __hash_rw_writer_unlock(h);
+               *ret_val = ret;
+               return 1;
+       }
+
+       FOR_EACH_BUCKET(cur_bkt, alt_bkt) {
+               ret = search_and_update(h, data, key, cur_bkt, sig);
+               if (ret != -1) {
+                       __hash_rw_writer_unlock(h);
+                       *ret_val = ret;
+                       return 1;
+               }
+       }
+
+       while (likely(curr_node->prev != NULL)) {
+               prev_node = curr_node->prev;
+               prev_bkt = prev_node->bkt;
+               prev_slot = curr_node->prev_slot;
+
+               prev_alt_bkt_idx = get_alt_bucket_index(h,
+                                       prev_node->cur_bkt_idx,
+                                       prev_bkt->sig_current[prev_slot]);
+
+               if (unlikely(&h->buckets[prev_alt_bkt_idx]
+                               != curr_bkt)) {
+                       /* revert it to empty, otherwise duplicated keys */
+                       curr_bkt->key_idx[curr_slot] = EMPTY_SLOT;
+                       __hash_rw_writer_unlock(h);
+                       return -1;
+               }
+
+               /* Need to swap current/alt sig to allow later
+                * Cuckoo insert to move elements back to its
+                * primary bucket if available
+                */
+               curr_bkt->sig_current[curr_slot] =
+                       prev_bkt->sig_current[prev_slot];
+               curr_bkt->key_idx[curr_slot] =
+                       prev_bkt->key_idx[prev_slot];
+
+               curr_slot = prev_slot;
+               curr_node = prev_node;
+               curr_bkt = curr_node->bkt;
+       }
+
+       curr_bkt->sig_current[curr_slot] = sig;
+       curr_bkt->key_idx[curr_slot] = new_idx;
+
+       __hash_rw_writer_unlock(h);
+
+       return 0;
 
 }
 
 /*
- * Function called to enqueue back an index in the cache/ring,
- * as slot has not being used and it can be used in the
- * next addition attempt.
+ * Make space for new key, using bfs Cuckoo Search and Multi-Writer safe
+ * Cuckoo
  */
-static inline void
-enqueue_slot_back(const struct rte_hash *h,
-               struct lcore_cache *cached_free_slots,
-               void *slot_id)
+static inline int
+rte_hash_cuckoo_make_space_mw(const struct rte_hash *h,
+                       struct rte_hash_bucket *bkt,
+                       struct rte_hash_bucket *sec_bkt,
+                       const struct rte_hash_key *key, void *data,
+                       uint16_t sig, uint32_t bucket_idx,
+                       uint32_t new_idx, int32_t *ret_val)
 {
-       if (h->hw_trans_mem_support) {
-               cached_free_slots->objs[cached_free_slots->len] = slot_id;
-               cached_free_slots->len++;
-       } else
-               rte_ring_sp_enqueue(h->free_slots, slot_id);
+       unsigned int i;
+       struct queue_node queue[RTE_HASH_BFS_QUEUE_MAX_LEN];
+       struct queue_node *tail, *head;
+       struct rte_hash_bucket *curr_bkt, *alt_bkt;
+       uint32_t cur_idx, alt_idx;
+
+       tail = queue;
+       head = queue + 1;
+       tail->bkt = bkt;
+       tail->prev = NULL;
+       tail->prev_slot = -1;
+       tail->cur_bkt_idx = bucket_idx;
+
+       /* Cuckoo bfs Search */
+       while (likely(tail != head && head <
+                                       queue + RTE_HASH_BFS_QUEUE_MAX_LEN -
+                                       RTE_HASH_BUCKET_ENTRIES)) {
+               curr_bkt = tail->bkt;
+               cur_idx = tail->cur_bkt_idx;
+               for (i = 0; i < RTE_HASH_BUCKET_ENTRIES; i++) {
+                       if (curr_bkt->key_idx[i] == EMPTY_SLOT) {
+                               int32_t ret = rte_hash_cuckoo_move_insert_mw(h,
+                                               bkt, sec_bkt, key, data,
+                                               tail, i, sig,
+                                               new_idx, ret_val);
+                               if (likely(ret != -1))
+                                       return ret;
+                       }
+
+                       /* Enqueue new node and keep prev node info */
+                       alt_idx = get_alt_bucket_index(h, cur_idx,
+                                               curr_bkt->sig_current[i]);
+                       alt_bkt = &(h->buckets[alt_idx]);
+                       head->bkt = alt_bkt;
+                       head->cur_bkt_idx = alt_idx;
+                       head->prev = tail;
+                       head->prev_slot = i;
+                       head++;
+               }
+               tail++;
+       }
+
+       return -ENOSPC;
 }
 
 static inline int32_t
 __rte_hash_add_key_with_hash(const struct rte_hash *h, const void *key,
                                                hash_sig_t sig, void *data)
 {
-       hash_sig_t alt_hash;
+       uint16_t short_sig;
        uint32_t prim_bucket_idx, sec_bucket_idx;
-       unsigned i;
-       struct rte_hash_bucket *prim_bkt, *sec_bkt;
-       struct rte_hash_key *new_k, *k, *keys = h->key_store;
+       struct rte_hash_bucket *prim_bkt, *sec_bkt, *cur_bkt;
+       struct rte_hash_key *new_k, *keys = h->key_store;
        void *slot_id = NULL;
-       uint32_t new_idx;
+       void *ext_bkt_id = NULL;
+       uint32_t new_idx, bkt_id;
        int ret;
        unsigned n_slots;
        unsigned lcore_id;
+       unsigned int i;
        struct lcore_cache *cached_free_slots = NULL;
-       unsigned int nr_pushes = 0;
-
-       if (h->add_key == ADD_KEY_MULTIWRITER)
-               rte_spinlock_lock(h->multiwriter_lock);
+       int32_t ret_val;
+       struct rte_hash_bucket *last;
 
-       prim_bucket_idx = sig & h->bucket_bitmask;
+       short_sig = get_short_sig(sig);
+       prim_bucket_idx = get_prim_bucket_index(h, sig);
+       sec_bucket_idx = get_alt_bucket_index(h, prim_bucket_idx, short_sig);
        prim_bkt = &h->buckets[prim_bucket_idx];
-       rte_prefetch0(prim_bkt);
-
-       alt_hash = rte_hash_secondary_hash(sig);
-       sec_bucket_idx = alt_hash & h->bucket_bitmask;
        sec_bkt = &h->buckets[sec_bucket_idx];
+       rte_prefetch0(prim_bkt);
        rte_prefetch0(sec_bkt);
 
-       /* Get a new slot for storing the new key */
-       if (h->hw_trans_mem_support) {
+       /* Check if key is already inserted in primary location */
+       __hash_rw_writer_lock(h);
+       ret = search_and_update(h, data, key, prim_bkt, short_sig);
+       if (ret != -1) {
+               __hash_rw_writer_unlock(h);
+               return ret;
+       }
+
+       /* Check if key is already inserted in secondary location */
+       FOR_EACH_BUCKET(cur_bkt, sec_bkt) {
+               ret = search_and_update(h, data, key, cur_bkt, short_sig);
+               if (ret != -1) {
+                       __hash_rw_writer_unlock(h);
+                       return ret;
+               }
+       }
+
+       __hash_rw_writer_unlock(h);
+
+       /* Did not find a match, so get a new slot for storing the new key */
+       if (h->multi_writer_support) {
                lcore_id = rte_lcore_id();
                cached_free_slots = &h->local_free_slots[lcore_id];
                /* Try to get a free slot from the local cache */
@@ -515,8 +858,7 @@ __rte_hash_add_key_with_hash(const struct rte_hash *h, const void *key,
                                        cached_free_slots->objs,
                                        LCORE_CACHE_SIZE, NULL);
                        if (n_slots == 0) {
-                               ret = -ENOSPC;
-                               goto failure;
+                               return -ENOSPC;
                        }
 
                        cached_free_slots->len += n_slots;
@@ -527,124 +869,108 @@ __rte_hash_add_key_with_hash(const struct rte_hash *h, const void *key,
                slot_id = cached_free_slots->objs[cached_free_slots->len];
        } else {
                if (rte_ring_sc_dequeue(h->free_slots, &slot_id) != 0) {
-                       ret = -ENOSPC;
-                       goto failure;
+                       return -ENOSPC;
                }
        }
 
        new_k = RTE_PTR_ADD(keys, (uintptr_t)slot_id * h->key_entry_size);
-       rte_prefetch0(new_k);
        new_idx = (uint32_t)((uintptr_t) slot_id);
+       /* Copy key */
+       rte_memcpy(new_k->key, key, h->key_len);
+       new_k->pdata = data;
 
-       /* Check if key is already inserted in primary location */
-       for (i = 0; i < RTE_HASH_BUCKET_ENTRIES; i++) {
-               if (prim_bkt->sig_current[i] == sig &&
-                               prim_bkt->sig_alt[i] == alt_hash) {
-                       k = (struct rte_hash_key *) ((char *)keys +
-                                       prim_bkt->key_idx[i] * h->key_entry_size);
-                       if (rte_hash_cmp_eq(key, k->key, h) == 0) {
-                               /* Enqueue index of free slot back in the ring. */
-                               enqueue_slot_back(h, cached_free_slots, slot_id);
-                               /* Update data */
-                               k->pdata = data;
-                               /*
-                                * Return index where key is stored,
-                                * subtracting the first dummy index
-                                */
-                               ret = prim_bkt->key_idx[i] - 1;
-                               goto failure;
-                       }
-               }
+
+       /* Find an empty slot and insert */
+       ret = rte_hash_cuckoo_insert_mw(h, prim_bkt, sec_bkt, key, data,
+                                       short_sig, new_idx, &ret_val);
+       if (ret == 0)
+               return new_idx - 1;
+       else if (ret == 1) {
+               enqueue_slot_back(h, cached_free_slots, slot_id);
+               return ret_val;
        }
 
-       /* Check if key is already inserted in secondary location */
-       for (i = 0; i < RTE_HASH_BUCKET_ENTRIES; i++) {
-               if (sec_bkt->sig_alt[i] == sig &&
-                               sec_bkt->sig_current[i] == alt_hash) {
-                       k = (struct rte_hash_key *) ((char *)keys +
-                                       sec_bkt->key_idx[i] * h->key_entry_size);
-                       if (rte_hash_cmp_eq(key, k->key, h) == 0) {
-                               /* Enqueue index of free slot back in the ring. */
-                               enqueue_slot_back(h, cached_free_slots, slot_id);
-                               /* Update data */
-                               k->pdata = data;
-                               /*
-                                * Return index where key is stored,
-                                * subtracting the first dummy index
-                                */
-                               ret = sec_bkt->key_idx[i] - 1;
-                               goto failure;
-                       }
-               }
+       /* Primary bucket full, need to make space for new entry */
+       ret = rte_hash_cuckoo_make_space_mw(h, prim_bkt, sec_bkt, key, data,
+                               short_sig, prim_bucket_idx, new_idx, &ret_val);
+       if (ret == 0)
+               return new_idx - 1;
+       else if (ret == 1) {
+               enqueue_slot_back(h, cached_free_slots, slot_id);
+               return ret_val;
        }
 
-       /* Copy key */
-       rte_memcpy(new_k->key, key, h->key_len);
-       new_k->pdata = data;
+       /* Also search secondary bucket to get better occupancy */
+       ret = rte_hash_cuckoo_make_space_mw(h, sec_bkt, prim_bkt, key, data,
+                               short_sig, sec_bucket_idx, new_idx, &ret_val);
 
-#if defined(RTE_ARCH_X86) /* currently only x86 support HTM */
-       if (h->add_key == ADD_KEY_MULTIWRITER_TM) {
-               ret = rte_hash_cuckoo_insert_mw_tm(prim_bkt,
-                               sig, alt_hash, new_idx);
-               if (ret >= 0)
-                       return new_idx - 1;
+       if (ret == 0)
+               return new_idx - 1;
+       else if (ret == 1) {
+               enqueue_slot_back(h, cached_free_slots, slot_id);
+               return ret_val;
+       }
 
-               /* Primary bucket full, need to make space for new entry */
-               ret = rte_hash_cuckoo_make_space_mw_tm(h, prim_bkt, sig,
-                                                       alt_hash, new_idx);
+       /* if ext table not enabled, we failed the insertion */
+       if (!h->ext_table_support) {
+               enqueue_slot_back(h, cached_free_slots, slot_id);
+               return ret;
+       }
 
-               if (ret >= 0)
-                       return new_idx - 1;
+       /* Now we need to go through the extendable bucket. Protection is needed
+        * to protect all extendable bucket processes.
+        */
+       __hash_rw_writer_lock(h);
+       /* We check for duplicates again since could be inserted before the lock */
+       ret = search_and_update(h, data, key, prim_bkt, short_sig);
+       if (ret != -1) {
+               enqueue_slot_back(h, cached_free_slots, slot_id);
+               goto failure;
+       }
 
-               /* Also search secondary bucket to get better occupancy */
-               ret = rte_hash_cuckoo_make_space_mw_tm(h, sec_bkt, sig,
-                                                       alt_hash, new_idx);
+       FOR_EACH_BUCKET(cur_bkt, sec_bkt) {
+               ret = search_and_update(h, data, key, cur_bkt, short_sig);
+               if (ret != -1) {
+                       enqueue_slot_back(h, cached_free_slots, slot_id);
+                       goto failure;
+               }
+       }
 
-               if (ret >= 0)
-                       return new_idx - 1;
-       } else {
-#endif
+       /* Search sec and ext buckets to find an empty entry to insert. */
+       FOR_EACH_BUCKET(cur_bkt, sec_bkt) {
                for (i = 0; i < RTE_HASH_BUCKET_ENTRIES; i++) {
                        /* Check if slot is available */
-                       if (likely(prim_bkt->key_idx[i] == EMPTY_SLOT)) {
-                               prim_bkt->sig_current[i] = sig;
-                               prim_bkt->sig_alt[i] = alt_hash;
-                               prim_bkt->key_idx[i] = new_idx;
-                               break;
+                       if (likely(cur_bkt->key_idx[i] == EMPTY_SLOT)) {
+                               cur_bkt->sig_current[i] = short_sig;
+                               cur_bkt->key_idx[i] = new_idx;
+                               __hash_rw_writer_unlock(h);
+                               return new_idx - 1;
                        }
                }
+       }
 
-               if (i != RTE_HASH_BUCKET_ENTRIES) {
-                       if (h->add_key == ADD_KEY_MULTIWRITER)
-                               rte_spinlock_unlock(h->multiwriter_lock);
-                       return new_idx - 1;
-               }
-
-               /* Primary bucket full, need to make space for new entry
-                * After recursive function.
-                * Insert the new entry in the position of the pushed entry
-                * if successful or return error and
-                * store the new slot back in the ring
-                */
-               ret = make_space_bucket(h, prim_bkt, &nr_pushes);
-               if (ret >= 0) {
-                       prim_bkt->sig_current[ret] = sig;
-                       prim_bkt->sig_alt[ret] = alt_hash;
-                       prim_bkt->key_idx[ret] = new_idx;
-                       if (h->add_key == ADD_KEY_MULTIWRITER)
-                               rte_spinlock_unlock(h->multiwriter_lock);
-                       return new_idx - 1;
-               }
-#if defined(RTE_ARCH_X86)
+       /* Failed to get an empty entry from extendable buckets. Link a new
+        * extendable bucket. We first get a free bucket from ring.
+        */
+       if (rte_ring_sc_dequeue(h->free_ext_bkts, &ext_bkt_id) != 0) {
+               ret = -ENOSPC;
+               goto failure;
        }
-#endif
-       /* Error in addition, store new slot back in the ring and return error */
-       enqueue_slot_back(h, cached_free_slots, (void *)((uintptr_t) new_idx));
+
+       bkt_id = (uint32_t)((uintptr_t)ext_bkt_id) - 1;
+       /* Use the first location of the new bucket */
+       (h->buckets_ext[bkt_id]).sig_current[0] = short_sig;
+       (h->buckets_ext[bkt_id]).key_idx[0] = new_idx;
+       /* Link the new bucket to sec bucket linked list */
+       last = rte_hash_get_last_bkt(sec_bkt);
+       last->next = &h->buckets_ext[bkt_id];
+       __hash_rw_writer_unlock(h);
+       return new_idx - 1;
 
 failure:
-       if (h->add_key == ADD_KEY_MULTIWRITER)
-               rte_spinlock_unlock(h->multiwriter_lock);
+       __hash_rw_writer_unlock(h);
        return ret;
+
 }
 
 int32_t
@@ -689,20 +1015,15 @@ rte_hash_add_key_data(const struct rte_hash *h, const void *key, void *data)
        else
                return ret;
 }
+
+/* Search one bucket to find the match key */
 static inline int32_t
-__rte_hash_lookup_with_hash(const struct rte_hash *h, const void *key,
-                                       hash_sig_t sig, void **data)
+search_one_bucket(const struct rte_hash *h, const void *key, uint16_t sig,
+                       void **data, const struct rte_hash_bucket *bkt)
 {
-       uint32_t bucket_idx;
-       hash_sig_t alt_hash;
-       unsigned i;
-       struct rte_hash_bucket *bkt;
+       int i;
        struct rte_hash_key *k, *keys = h->key_store;
 
-       bucket_idx = sig & h->bucket_bitmask;
-       bkt = &h->buckets[bucket_idx];
-
-       /* Check if key is in primary location */
        for (i = 0; i < RTE_HASH_BUCKET_ENTRIES; i++) {
                if (bkt->sig_current[i] == sig &&
                                bkt->key_idx[i] != EMPTY_SLOT) {
@@ -719,30 +1040,43 @@ __rte_hash_lookup_with_hash(const struct rte_hash *h, const void *key,
                        }
                }
        }
+       return -1;
+}
 
+static inline int32_t
+__rte_hash_lookup_with_hash(const struct rte_hash *h, const void *key,
+                                       hash_sig_t sig, void **data)
+{
+       uint32_t prim_bucket_idx, sec_bucket_idx;
+       struct rte_hash_bucket *bkt, *cur_bkt;
+       int ret;
+       uint16_t short_sig;
+
+       short_sig = get_short_sig(sig);
+       prim_bucket_idx = get_prim_bucket_index(h, sig);
+       sec_bucket_idx = get_alt_bucket_index(h, prim_bucket_idx, short_sig);
+       bkt = &h->buckets[prim_bucket_idx];
+
+       __hash_rw_reader_lock(h);
+
+       /* Check if key is in primary location */
+       ret = search_one_bucket(h, key, short_sig, data, bkt);
+       if (ret != -1) {
+               __hash_rw_reader_unlock(h);
+               return ret;
+       }
        /* Calculate secondary hash */
-       alt_hash = rte_hash_secondary_hash(sig);
-       bucket_idx = alt_hash & h->bucket_bitmask;
-       bkt = &h->buckets[bucket_idx];
+       bkt = &h->buckets[sec_bucket_idx];
 
        /* Check if key is in secondary location */
-       for (i = 0; i < RTE_HASH_BUCKET_ENTRIES; i++) {
-               if (bkt->sig_current[i] == alt_hash &&
-                               bkt->sig_alt[i] == sig) {
-                       k = (struct rte_hash_key *) ((char *)keys +
-                                       bkt->key_idx[i] * h->key_entry_size);
-                       if (rte_hash_cmp_eq(key, k->key, h) == 0) {
-                               if (data != NULL)
-                                       *data = k->pdata;
-                               /*
-                                * Return index where key is stored,
-                                * subtracting the first dummy index
-                                */
-                               return bkt->key_idx[i] - 1;
-                       }
+       FOR_EACH_BUCKET(cur_bkt, bkt) {
+               ret = search_one_bucket(h, key, short_sig, data, cur_bkt);
+               if (ret != -1) {
+                       __hash_rw_reader_unlock(h);
+                       return ret;
                }
        }
-
+       __hash_rw_reader_unlock(h);
        return -ENOENT;
 }
 
@@ -783,8 +1117,7 @@ remove_entry(const struct rte_hash *h, struct rte_hash_bucket *bkt, unsigned i)
        struct lcore_cache *cached_free_slots;
 
        bkt->sig_current[i] = NULL_SIGNATURE;
-       bkt->sig_alt[i] = NULL_SIGNATURE;
-       if (h->hw_trans_mem_support) {
+       if (h->multi_writer_support) {
                lcore_id = rte_lcore_id();
                cached_free_slots = &h->local_free_slots[lcore_id];
                /* Cache full, need to free it. */
@@ -805,21 +1138,40 @@ remove_entry(const struct rte_hash *h, struct rte_hash_bucket *bkt, unsigned i)
        }
 }
 
+/* Compact the linked list by moving key from last entry in linked list to the
+ * empty slot.
+ */
+static inline void
+__rte_hash_compact_ll(struct rte_hash_bucket *cur_bkt, int pos) {
+       int i;
+       struct rte_hash_bucket *last_bkt;
+
+       if (!cur_bkt->next)
+               return;
+
+       last_bkt = rte_hash_get_last_bkt(cur_bkt);
+
+       for (i = RTE_HASH_BUCKET_ENTRIES - 1; i >= 0; i--) {
+               if (last_bkt->key_idx[i] != EMPTY_SLOT) {
+                       cur_bkt->key_idx[pos] = last_bkt->key_idx[i];
+                       cur_bkt->sig_current[pos] = last_bkt->sig_current[i];
+                       last_bkt->sig_current[i] = NULL_SIGNATURE;
+                       last_bkt->key_idx[i] = EMPTY_SLOT;
+                       return;
+               }
+       }
+}
+
+/* Search one bucket and remove the matched key */
 static inline int32_t
-__rte_hash_del_key_with_hash(const struct rte_hash *h, const void *key,
-                                               hash_sig_t sig)
+search_and_remove(const struct rte_hash *h, const void *key,
+                       struct rte_hash_bucket *bkt, uint16_t sig, int *pos)
 {
-       uint32_t bucket_idx;
-       hash_sig_t alt_hash;
-       unsigned i;
-       struct rte_hash_bucket *bkt;
        struct rte_hash_key *k, *keys = h->key_store;
+       unsigned int i;
        int32_t ret;
 
-       bucket_idx = sig & h->bucket_bitmask;
-       bkt = &h->buckets[bucket_idx];
-
-       /* Check if key is in primary location */
+       /* Check if key is in bucket */
        for (i = 0; i < RTE_HASH_BUCKET_ENTRIES; i++) {
                if (bkt->sig_current[i] == sig &&
                                bkt->key_idx[i] != EMPTY_SLOT) {
@@ -828,43 +1180,85 @@ __rte_hash_del_key_with_hash(const struct rte_hash *h, const void *key,
                        if (rte_hash_cmp_eq(key, k->key, h) == 0) {
                                remove_entry(h, bkt, i);
 
-                               /*
-                                * Return index where key is stored,
+                               /* Return index where key is stored,
                                 * subtracting the first dummy index
                                 */
                                ret = bkt->key_idx[i] - 1;
                                bkt->key_idx[i] = EMPTY_SLOT;
+                               *pos = i;
                                return ret;
                        }
                }
        }
+       return -1;
+}
 
-       /* Calculate secondary hash */
-       alt_hash = rte_hash_secondary_hash(sig);
-       bucket_idx = alt_hash & h->bucket_bitmask;
-       bkt = &h->buckets[bucket_idx];
+static inline int32_t
+__rte_hash_del_key_with_hash(const struct rte_hash *h, const void *key,
+                                               hash_sig_t sig)
+{
+       uint32_t prim_bucket_idx, sec_bucket_idx;
+       struct rte_hash_bucket *prim_bkt, *sec_bkt, *prev_bkt, *last_bkt;
+       struct rte_hash_bucket *cur_bkt;
+       int pos;
+       int32_t ret, i;
+       uint16_t short_sig;
+
+       short_sig = get_short_sig(sig);
+       prim_bucket_idx = get_prim_bucket_index(h, sig);
+       sec_bucket_idx = get_alt_bucket_index(h, prim_bucket_idx, short_sig);
+       prim_bkt = &h->buckets[prim_bucket_idx];
 
-       /* Check if key is in secondary location */
-       for (i = 0; i < RTE_HASH_BUCKET_ENTRIES; i++) {
-               if (bkt->sig_current[i] == alt_hash &&
-                               bkt->key_idx[i] != EMPTY_SLOT) {
-                       k = (struct rte_hash_key *) ((char *)keys +
-                                       bkt->key_idx[i] * h->key_entry_size);
-                       if (rte_hash_cmp_eq(key, k->key, h) == 0) {
-                               remove_entry(h, bkt, i);
+       __hash_rw_writer_lock(h);
+       /* look for key in primary bucket */
+       ret = search_and_remove(h, key, prim_bkt, short_sig, &pos);
+       if (ret != -1) {
+               __rte_hash_compact_ll(prim_bkt, pos);
+               last_bkt = prim_bkt->next;
+               prev_bkt = prim_bkt;
+               goto return_bkt;
+       }
 
-                               /*
-                                * Return index where key is stored,
-                                * subtracting the first dummy index
-                                */
-                               ret = bkt->key_idx[i] - 1;
-                               bkt->key_idx[i] = EMPTY_SLOT;
-                               return ret;
-                       }
+       /* Calculate secondary hash */
+       sec_bkt = &h->buckets[sec_bucket_idx];
+
+       FOR_EACH_BUCKET(cur_bkt, sec_bkt) {
+               ret = search_and_remove(h, key, cur_bkt, short_sig, &pos);
+               if (ret != -1) {
+                       __rte_hash_compact_ll(cur_bkt, pos);
+                       last_bkt = sec_bkt->next;
+                       prev_bkt = sec_bkt;
+                       goto return_bkt;
                }
        }
 
+       __hash_rw_writer_unlock(h);
        return -ENOENT;
+
+/* Search last bucket to see if empty to be recycled */
+return_bkt:
+       if (!last_bkt) {
+               __hash_rw_writer_unlock(h);
+               return ret;
+       }
+       while (last_bkt->next) {
+               prev_bkt = last_bkt;
+               last_bkt = last_bkt->next;
+       }
+
+       for (i = 0; i < RTE_HASH_BUCKET_ENTRIES; i++) {
+               if (last_bkt->key_idx[i] != EMPTY_SLOT)
+                       break;
+       }
+       /* found empty bucket and recycle */
+       if (i == RTE_HASH_BUCKET_ENTRIES) {
+               prev_bkt->next = last_bkt->next = NULL;
+               uint32_t index = last_bkt - h->buckets_ext + 1;
+               rte_ring_sp_enqueue(h->free_ext_bkts, (void *)(uintptr_t)index);
+       }
+
+       __hash_rw_writer_unlock(h);
+       return ret;
 }
 
 int32_t
@@ -906,55 +1300,35 @@ static inline void
 compare_signatures(uint32_t *prim_hash_matches, uint32_t *sec_hash_matches,
                        const struct rte_hash_bucket *prim_bkt,
                        const struct rte_hash_bucket *sec_bkt,
-                       hash_sig_t prim_hash, hash_sig_t sec_hash,
+                       uint16_t sig,
                        enum rte_hash_sig_compare_function sig_cmp_fn)
 {
        unsigned int i;
 
+       /* For match mask the first bit of every two bits indicates the match */
        switch (sig_cmp_fn) {
-#ifdef RTE_MACHINE_CPUFLAG_AVX2
-       case RTE_HASH_COMPARE_AVX2:
-               *prim_hash_matches = _mm256_movemask_ps((__m256)_mm256_cmpeq_epi32(
-                               _mm256_load_si256(
-                                       (__m256i const *)prim_bkt->sig_current),
-                               _mm256_set1_epi32(prim_hash)));
-               *sec_hash_matches = _mm256_movemask_ps((__m256)_mm256_cmpeq_epi32(
-                               _mm256_load_si256(
-                                       (__m256i const *)sec_bkt->sig_current),
-                               _mm256_set1_epi32(sec_hash)));
-               break;
-#endif
 #ifdef RTE_MACHINE_CPUFLAG_SSE2
        case RTE_HASH_COMPARE_SSE:
-               /* Compare the first 4 signatures in the bucket */
-               *prim_hash_matches = _mm_movemask_ps((__m128)_mm_cmpeq_epi16(
+               /* Compare all signatures in the bucket */
+               *prim_hash_matches = _mm_movemask_epi8(_mm_cmpeq_epi16(
                                _mm_load_si128(
                                        (__m128i const *)prim_bkt->sig_current),
-                               _mm_set1_epi32(prim_hash)));
-               *prim_hash_matches |= (_mm_movemask_ps((__m128)_mm_cmpeq_epi16(
-                               _mm_load_si128(
-                                       (__m128i const *)&prim_bkt->sig_current[4]),
-                               _mm_set1_epi32(prim_hash)))) << 4;
-               /* Compare the first 4 signatures in the bucket */
-               *sec_hash_matches = _mm_movemask_ps((__m128)_mm_cmpeq_epi16(
+                               _mm_set1_epi16(sig)));
+               /* Compare all signatures in the bucket */
+               *sec_hash_matches = _mm_movemask_epi8(_mm_cmpeq_epi16(
                                _mm_load_si128(
                                        (__m128i const *)sec_bkt->sig_current),
-                               _mm_set1_epi32(sec_hash)));
-               *sec_hash_matches |= (_mm_movemask_ps((__m128)_mm_cmpeq_epi16(
-                               _mm_load_si128(
-                                       (__m128i const *)&sec_bkt->sig_current[4]),
-                               _mm_set1_epi32(sec_hash)))) << 4;
+                               _mm_set1_epi16(sig)));
                break;
 #endif
        default:
                for (i = 0; i < RTE_HASH_BUCKET_ENTRIES; i++) {
                        *prim_hash_matches |=
-                               ((prim_hash == prim_bkt->sig_current[i]) << i);
+                               ((sig == prim_bkt->sig_current[i]) << (i << 1));
                        *sec_hash_matches |=
-                               ((sec_hash == sec_bkt->sig_current[i]) << i);
+                               ((sig == sec_bkt->sig_current[i]) << (i << 1));
                }
        }
-
 }
 
 #define PREFETCH_OFFSET 4
@@ -965,12 +1339,16 @@ __rte_hash_lookup_bulk(const struct rte_hash *h, const void **keys,
 {
        uint64_t hits = 0;
        int32_t i;
+       int32_t ret;
        uint32_t prim_hash[RTE_HASH_LOOKUP_BULK_MAX];
-       uint32_t sec_hash[RTE_HASH_LOOKUP_BULK_MAX];
+       uint32_t prim_index[RTE_HASH_LOOKUP_BULK_MAX];
+       uint32_t sec_index[RTE_HASH_LOOKUP_BULK_MAX];
+       uint16_t sig[RTE_HASH_LOOKUP_BULK_MAX];
        const struct rte_hash_bucket *primary_bkt[RTE_HASH_LOOKUP_BULK_MAX];
        const struct rte_hash_bucket *secondary_bkt[RTE_HASH_LOOKUP_BULK_MAX];
        uint32_t prim_hitmask[RTE_HASH_LOOKUP_BULK_MAX] = {0};
        uint32_t sec_hitmask[RTE_HASH_LOOKUP_BULK_MAX] = {0};
+       struct rte_hash_bucket *cur_bkt, *next_bkt;
 
        /* Prefetch first keys */
        for (i = 0; i < PREFETCH_OFFSET && i < num_keys; i++)
@@ -984,10 +1362,13 @@ __rte_hash_lookup_bulk(const struct rte_hash *h, const void **keys,
                rte_prefetch0(keys[i + PREFETCH_OFFSET]);
 
                prim_hash[i] = rte_hash_hash(h, keys[i]);
-               sec_hash[i] = rte_hash_secondary_hash(prim_hash[i]);
 
-               primary_bkt[i] = &h->buckets[prim_hash[i] & h->bucket_bitmask];
-               secondary_bkt[i] = &h->buckets[sec_hash[i] & h->bucket_bitmask];
+               sig[i] = get_short_sig(prim_hash[i]);
+               prim_index[i] = get_prim_bucket_index(h, prim_hash[i]);
+               sec_index[i] = get_alt_bucket_index(h, prim_index[i], sig[i]);
+
+               primary_bkt[i] = &h->buckets[prim_index[i]];
+               secondary_bkt[i] = &h->buckets[sec_index[i]];
 
                rte_prefetch0(primary_bkt[i]);
                rte_prefetch0(secondary_bkt[i]);
@@ -996,23 +1377,28 @@ __rte_hash_lookup_bulk(const struct rte_hash *h, const void **keys,
        /* Calculate and prefetch rest of the buckets */
        for (; i < num_keys; i++) {
                prim_hash[i] = rte_hash_hash(h, keys[i]);
-               sec_hash[i] = rte_hash_secondary_hash(prim_hash[i]);
 
-               primary_bkt[i] = &h->buckets[prim_hash[i] & h->bucket_bitmask];
-               secondary_bkt[i] = &h->buckets[sec_hash[i] & h->bucket_bitmask];
+               sig[i] = get_short_sig(prim_hash[i]);
+               prim_index[i] = get_prim_bucket_index(h, prim_hash[i]);
+               sec_index[i] = get_alt_bucket_index(h, prim_index[i], sig[i]);
+
+               primary_bkt[i] = &h->buckets[prim_index[i]];
+               secondary_bkt[i] = &h->buckets[sec_index[i]];
 
                rte_prefetch0(primary_bkt[i]);
                rte_prefetch0(secondary_bkt[i]);
        }
 
+       __hash_rw_reader_lock(h);
        /* Compare signatures and prefetch key slot of first hit */
        for (i = 0; i < num_keys; i++) {
                compare_signatures(&prim_hitmask[i], &sec_hitmask[i],
                                primary_bkt[i], secondary_bkt[i],
-                               prim_hash[i], sec_hash[i], h->sig_cmp_fn);
+                               sig[i], h->sig_cmp_fn);
 
                if (prim_hitmask[i]) {
-                       uint32_t first_hit = __builtin_ctzl(prim_hitmask[i]);
+                       uint32_t first_hit =
+                                       __builtin_ctzl(prim_hitmask[i]) >> 1;
                        uint32_t key_idx = primary_bkt[i]->key_idx[first_hit];
                        const struct rte_hash_key *key_slot =
                                (const struct rte_hash_key *)(
@@ -1023,7 +1409,8 @@ __rte_hash_lookup_bulk(const struct rte_hash *h, const void **keys,
                }
 
                if (sec_hitmask[i]) {
-                       uint32_t first_hit = __builtin_ctzl(sec_hitmask[i]);
+                       uint32_t first_hit =
+                                       __builtin_ctzl(sec_hitmask[i]) >> 1;
                        uint32_t key_idx = secondary_bkt[i]->key_idx[first_hit];
                        const struct rte_hash_key *key_slot =
                                (const struct rte_hash_key *)(
@@ -1037,7 +1424,8 @@ __rte_hash_lookup_bulk(const struct rte_hash *h, const void **keys,
        for (i = 0; i < num_keys; i++) {
                positions[i] = -ENOENT;
                while (prim_hitmask[i]) {
-                       uint32_t hit_index = __builtin_ctzl(prim_hitmask[i]);
+                       uint32_t hit_index =
+                                       __builtin_ctzl(prim_hitmask[i]) >> 1;
 
                        uint32_t key_idx = primary_bkt[i]->key_idx[hit_index];
                        const struct rte_hash_key *key_slot =
@@ -1056,11 +1444,12 @@ __rte_hash_lookup_bulk(const struct rte_hash *h, const void **keys,
                                positions[i] = key_idx - 1;
                                goto next_key;
                        }
-                       prim_hitmask[i] &= ~(1 << (hit_index));
+                       prim_hitmask[i] &= ~(3ULL << (hit_index << 1));
                }
 
                while (sec_hitmask[i]) {
-                       uint32_t hit_index = __builtin_ctzl(sec_hitmask[i]);
+                       uint32_t hit_index =
+                                       __builtin_ctzl(sec_hitmask[i]) >> 1;
 
                        uint32_t key_idx = secondary_bkt[i]->key_idx[hit_index];
                        const struct rte_hash_key *key_slot =
@@ -1080,13 +1469,43 @@ __rte_hash_lookup_bulk(const struct rte_hash *h, const void **keys,
                                positions[i] = key_idx - 1;
                                goto next_key;
                        }
-                       sec_hitmask[i] &= ~(1 << (hit_index));
+                       sec_hitmask[i] &= ~(3ULL << (hit_index << 1));
                }
 
 next_key:
                continue;
        }
 
+       /* all found, do not need to go through ext bkt */
+       if ((hits == ((1ULL << num_keys) - 1)) || !h->ext_table_support) {
+               if (hit_mask != NULL)
+                       *hit_mask = hits;
+               __hash_rw_reader_unlock(h);
+               return;
+       }
+
+       /* need to check ext buckets for match */
+       for (i = 0; i < num_keys; i++) {
+               if ((hits & (1ULL << i)) != 0)
+                       continue;
+               next_bkt = secondary_bkt[i]->next;
+               FOR_EACH_BUCKET(cur_bkt, next_bkt) {
+                       if (data != NULL)
+                               ret = search_one_bucket(h, keys[i],
+                                               sig[i], &data[i], cur_bkt);
+                       else
+                               ret = search_one_bucket(h, keys[i],
+                                               sig[i], NULL, cur_bkt);
+                       if (ret != -1) {
+                               positions[i] = ret;
+                               hits |= 1ULL << i;
+                               break;
+                       }
+               }
+       }
+
+       __hash_rw_reader_unlock(h);
+
        if (hit_mask != NULL)
                *hit_mask = hits;
 }
@@ -1127,35 +1546,69 @@ rte_hash_iterate(const struct rte_hash *h, const void **key, void **data, uint32
 
        RETURN_IF_TRUE(((h == NULL) || (next == NULL)), -EINVAL);
 
-       const uint32_t total_entries = h->num_buckets * RTE_HASH_BUCKET_ENTRIES;
-       /* Out of bounds */
-       if (*next >= total_entries)
-               return -ENOENT;
+       const uint32_t total_entries_main = h->num_buckets *
+                                                       RTE_HASH_BUCKET_ENTRIES;
+       const uint32_t total_entries = total_entries_main << 1;
+
+       /* Out of bounds of all buckets (both main table and ext table) */
+       if (*next >= total_entries_main)
+               goto extend_table;
 
        /* Calculate bucket and index of current iterator */
        bucket_idx = *next / RTE_HASH_BUCKET_ENTRIES;
        idx = *next % RTE_HASH_BUCKET_ENTRIES;
 
        /* If current position is empty, go to the next one */
-       while (h->buckets[bucket_idx].key_idx[idx] == EMPTY_SLOT) {
+       while ((position = h->buckets[bucket_idx].key_idx[idx]) == EMPTY_SLOT) {
                (*next)++;
                /* End of table */
-               if (*next == total_entries)
-                       return -ENOENT;
+               if (*next == total_entries_main)
+                       goto extend_table;
                bucket_idx = *next / RTE_HASH_BUCKET_ENTRIES;
                idx = *next % RTE_HASH_BUCKET_ENTRIES;
        }
 
-       /* Get position of entry in key table */
-       position = h->buckets[bucket_idx].key_idx[idx];
+       __hash_rw_reader_lock(h);
        next_key = (struct rte_hash_key *) ((char *)h->key_store +
                                position * h->key_entry_size);
        /* Return key and data */
        *key = next_key->key;
        *data = next_key->pdata;
 
+       __hash_rw_reader_unlock(h);
+
        /* Increment iterator */
        (*next)++;
 
        return position - 1;
+
+/* Begin to iterate extendable buckets */
+extend_table:
+       /* Out of total bound or if ext bucket feature is not enabled */
+       if (*next >= total_entries || !h->ext_table_support)
+               return -ENOENT;
+
+       bucket_idx = (*next - total_entries_main) / RTE_HASH_BUCKET_ENTRIES;
+       idx = (*next - total_entries_main) % RTE_HASH_BUCKET_ENTRIES;
+
+       while ((position = h->buckets_ext[bucket_idx].key_idx[idx]) == EMPTY_SLOT) {
+               (*next)++;
+               if (*next == total_entries)
+                       return -ENOENT;
+               bucket_idx = (*next - total_entries_main) /
+                                               RTE_HASH_BUCKET_ENTRIES;
+               idx = (*next - total_entries_main) % RTE_HASH_BUCKET_ENTRIES;
+       }
+       __hash_rw_reader_lock(h);
+       next_key = (struct rte_hash_key *) ((char *)h->key_store +
+                               position * h->key_entry_size);
+       /* Return key and data */
+       *key = next_key->key;
+       *data = next_key->pdata;
+
+       __hash_rw_reader_unlock(h);
+
+       /* Increment iterator */
+       (*next)++;
+       return position - 1;
 }