hash: reorganize bucket structure

Move current signatures of all entries together in the bucket
and same with all alternative signatures, instead of having
current and alternative signatures together per entry in the bucket.
This will be benefitial in the next commits, where a vectorized
comparison will be performed, achieving better performance.

The alternative signatures have been moved away from
the current signatures, to make the key indices be consecutive
to the current signatures, as these two fields are used by lookup,
so they are in the same cache line.

Signed-off-by: Byron Marohn <byron.marohn@intel.com>
Signed-off-by: Saikrishna Edupuganti <saikrishna.edupuganti@intel.com>
Acked-by: Bruce Richardson <bruce.richardson@intel.com>
Acked-by: Sameh Gobriel <sameh.gobriel@intel.com>

diff --git a/lib/librte_hash/rte_cuckoo_hash.c b/lib/librte_hash/rte_cuckoo_hash.c
index 4de4422bbd46119185f9c17922650419964d0734..a7ee2b9c03d380b768db6bdae174f7ab8c653c90 100644 (file)
--- a/lib/librte_hash/rte_cuckoo_hash.c
+++ b/lib/librte_hash/rte_cuckoo_hash.c
@@ -421,7 +421,7 @@ make_space_bucket(const struct rte_hash *h, struct rte_hash_bucket *bkt)
         */
        for (i = 0; i < RTE_HASH_BUCKET_ENTRIES; i++) {
                /* Search for space in alternative locations */
-               next_bucket_idx = bkt->signatures[i].alt & h->bucket_bitmask;
+               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)
@@ -434,8 +434,8 @@ make_space_bucket(const struct rte_hash *h, struct rte_hash_bucket *bkt)
 
        /* Alternative location has spare room (end of recursive function) */
        if (i != RTE_HASH_BUCKET_ENTRIES) {
-               next_bkt[i]->signatures[j].alt = bkt->signatures[i].current;
-               next_bkt[i]->signatures[j].current = bkt->signatures[i].alt;
+               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;
        }
@@ -461,8 +461,8 @@ make_space_bucket(const struct rte_hash *h, struct rte_hash_bucket *bkt)
         */
        bkt->flag[i] = 0;
        if (ret >= 0) {
-               next_bkt[i]->signatures[ret].alt = bkt->signatures[i].current;
-               next_bkt[i]->signatures[ret].current = bkt->signatures[i].alt;
+               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
@@ -544,8 +544,8 @@ __rte_hash_add_key_with_hash(const struct rte_hash *h, const void *key,
 
        /* Check if key is already inserted in primary location */
        for (i = 0; i < RTE_HASH_BUCKET_ENTRIES; i++) {
-               if (prim_bkt->signatures[i].current == sig &&
-                               prim_bkt->signatures[i].alt == alt_hash) {
+               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) {
@@ -564,8 +564,8 @@ __rte_hash_add_key_with_hash(const struct rte_hash *h, const void *key,
 
        /* Check if key is already inserted in secondary location */
        for (i = 0; i < RTE_HASH_BUCKET_ENTRIES; i++) {
-               if (sec_bkt->signatures[i].alt == sig &&
-                               sec_bkt->signatures[i].current == alt_hash) {
+               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) {
@@ -611,8 +611,8 @@ __rte_hash_add_key_with_hash(const struct rte_hash *h, const void *key,
                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->signatures[i].current = sig;
-                               prim_bkt->signatures[i].alt = alt_hash;
+                               prim_bkt->sig_current[i] = sig;
+                               prim_bkt->sig_alt[i] = alt_hash;
                                prim_bkt->key_idx[i] = new_idx;
                                break;
                        }
@@ -632,8 +632,8 @@ __rte_hash_add_key_with_hash(const struct rte_hash *h, const void *key,
                 */
                ret = make_space_bucket(h, prim_bkt);
                if (ret >= 0) {
-                       prim_bkt->signatures[ret].current = sig;
-                       prim_bkt->signatures[ret].alt = alt_hash;
+                       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);
@@ -707,7 +707,7 @@ __rte_hash_lookup_with_hash(const struct rte_hash *h, const void *key,
 
        /* Check if key is in primary location */
        for (i = 0; i < RTE_HASH_BUCKET_ENTRIES; i++) {
-               if (bkt->signatures[i].current == sig &&
+               if (bkt->sig_current[i] == sig &&
                                bkt->key_idx[i] != EMPTY_SLOT) {
                        k = (struct rte_hash_key *) ((char *)keys +
                                        bkt->key_idx[i] * h->key_entry_size);
@@ -730,8 +730,8 @@ __rte_hash_lookup_with_hash(const struct rte_hash *h, const void *key,
 
        /* Check if key is in secondary location */
        for (i = 0; i < RTE_HASH_BUCKET_ENTRIES; i++) {
-               if (bkt->signatures[i].current == alt_hash &&
-                               bkt->signatures[i].alt == sig) {
+               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) {
@@ -785,7 +785,8 @@ remove_entry(const struct rte_hash *h, struct rte_hash_bucket *bkt, unsigned i)
        unsigned lcore_id, n_slots;
        struct lcore_cache *cached_free_slots;
 
-       bkt->signatures[i].sig = NULL_SIGNATURE;
+       bkt->sig_current[i] = NULL_SIGNATURE;
+       bkt->sig_alt[i] = NULL_SIGNATURE;
        if (h->hw_trans_mem_support) {
                lcore_id = rte_lcore_id();
                cached_free_slots = &h->local_free_slots[lcore_id];
@@ -823,7 +824,7 @@ __rte_hash_del_key_with_hash(const struct rte_hash *h, const void *key,
 
        /* Check if key is in primary location */
        for (i = 0; i < RTE_HASH_BUCKET_ENTRIES; i++) {
-               if (bkt->signatures[i].current == sig &&
+               if (bkt->sig_current[i] == sig &&
                                bkt->key_idx[i] != EMPTY_SLOT) {
                        k = (struct rte_hash_key *) ((char *)keys +
                                        bkt->key_idx[i] * h->key_entry_size);
@@ -848,7 +849,7 @@ __rte_hash_del_key_with_hash(const struct rte_hash *h, const void *key,
 
        /* Check if key is in secondary location */
        for (i = 0; i < RTE_HASH_BUCKET_ENTRIES; i++) {
-               if (bkt->signatures[i].current == alt_hash &&
+               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);
@@ -957,8 +958,8 @@ lookup_stage2(unsigned idx, hash_sig_t prim_hash, hash_sig_t sec_hash,
        prim_hash_matches = 1 << RTE_HASH_BUCKET_ENTRIES;
        sec_hash_matches = 1 << RTE_HASH_BUCKET_ENTRIES;
        for (i = 0; i < RTE_HASH_BUCKET_ENTRIES; i++) {
-               prim_hash_matches |= ((prim_hash == prim_bkt->signatures[i].current) << i);
-               sec_hash_matches |= ((sec_hash == sec_bkt->signatures[i].current) << i);
+               prim_hash_matches |= ((prim_hash == prim_bkt->sig_current[i]) << i);
+               sec_hash_matches |= ((sec_hash == sec_bkt->sig_current[i]) << i);
        }
 
        key_idx = prim_bkt->key_idx[__builtin_ctzl(prim_hash_matches)];

diff --git a/lib/librte_hash/rte_cuckoo_hash.h b/lib/librte_hash/rte_cuckoo_hash.h
index 27a47e5dc993d7e7c1905e2fc2091e652f6f33e9..6549731dc2b3b1072e8ac551640367dc52bbac45 100644 (file)
--- a/lib/librte_hash/rte_cuckoo_hash.h
+++ b/lib/librte_hash/rte_cuckoo_hash.h
@@ -151,17 +151,6 @@ struct lcore_cache {
        void *objs[LCORE_CACHE_SIZE]; /**< Cache objects */
 } __rte_cache_aligned;
 
-/* Structure storing both primary and secondary hashes */
-struct rte_hash_signatures {
-       union {
-               struct {
-                       hash_sig_t current;
-                       hash_sig_t alt;
-               };
-               uint64_t sig;
-       };
-};
-
 /* Structure that stores key-value pair */
 struct rte_hash_key {
        union {
@@ -174,9 +163,13 @@ struct rte_hash_key {
 
 /** Bucket structure */
 struct rte_hash_bucket {
-       struct rte_hash_signatures signatures[RTE_HASH_BUCKET_ENTRIES];
+       hash_sig_t sig_current[RTE_HASH_BUCKET_ENTRIES];
+
        /* Includes dummy key index that always contains index 0 */
        uint32_t key_idx[RTE_HASH_BUCKET_ENTRIES + 1];
+
+       hash_sig_t sig_alt[RTE_HASH_BUCKET_ENTRIES];
+
        uint8_t flag[RTE_HASH_BUCKET_ENTRIES];
 } __rte_cache_aligned;
 

diff --git a/lib/librte_hash/rte_cuckoo_hash_x86.h b/lib/librte_hash/rte_cuckoo_hash_x86.h
index 7ffa56f9594fb09611d113b14ef9a419c61eca71..47aec6d130022cd019884baf50bf599e269d7aec 100644 (file)
--- a/lib/librte_hash/rte_cuckoo_hash_x86.h
+++ b/lib/librte_hash/rte_cuckoo_hash_x86.h
@@ -54,8 +54,8 @@ rte_hash_cuckoo_insert_mw_tm(struct rte_hash_bucket *prim_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->signatures[i].current = sig;
-                                       prim_bkt->signatures[i].alt = alt_hash;
+                                       prim_bkt->sig_current[i] = sig;
+                                       prim_bkt->sig_alt[i] = alt_hash;
                                        prim_bkt->key_idx[i] = new_idx;
                                        break;
                                }
@@ -101,7 +101,7 @@ rte_hash_cuckoo_move_insert_mw_tm(const struct rte_hash *h,
                                prev_slot = curr_node->prev_slot;
 
                                prev_alt_bkt_idx
-                                       = prev_bkt->signatures[prev_slot].alt
+                                       = prev_bkt->sig_alt[prev_slot]
                                            & h->bucket_bitmask;
 
                                if (unlikely(&h->buckets[prev_alt_bkt_idx]
@@ -113,10 +113,10 @@ rte_hash_cuckoo_move_insert_mw_tm(const struct rte_hash *h,
                                 * Cuckoo insert to move elements back to its
                                 * primary bucket if available
                                 */
-                               curr_bkt->signatures[curr_slot].alt =
-                                   prev_bkt->signatures[prev_slot].current;
-                               curr_bkt->signatures[curr_slot].current =
-                                   prev_bkt->signatures[prev_slot].alt;
+                               curr_bkt->sig_alt[curr_slot] =
+                                   prev_bkt->sig_current[prev_slot];
+                               curr_bkt->sig_current[curr_slot] =
+                                   prev_bkt->sig_alt[prev_slot];
                                curr_bkt->key_idx[curr_slot]
                                    = prev_bkt->key_idx[prev_slot];
 
@@ -125,8 +125,8 @@ rte_hash_cuckoo_move_insert_mw_tm(const struct rte_hash *h,
                                curr_bkt = curr_node->bkt;
                        }
 
-                       curr_bkt->signatures[curr_slot].current = sig;
-                       curr_bkt->signatures[curr_slot].alt = alt_hash;
+                       curr_bkt->sig_current[curr_slot] = sig;
+                       curr_bkt->sig_alt[curr_slot] = alt_hash;
                        curr_bkt->key_idx[curr_slot] = new_idx;
 
                        rte_xend();
@@ -178,7 +178,7 @@ rte_hash_cuckoo_make_space_mw_tm(const struct rte_hash *h,
                        }
 
                        /* Enqueue new node and keep prev node info */
-                       alt_bkt = &(h->buckets[curr_bkt->signatures[i].alt
+                       alt_bkt = &(h->buckets[curr_bkt->sig_alt[i]
                                                    & h->bucket_bitmask]);
                        head->bkt = alt_bkt;
                        head->prev = tail;