[dpdk-dev] [PATCH v5 4/4] hash: use partial-key hashing

Wang, Yipeng1 yipeng1.wang at intel.com
Wed Oct 3 02:43:10 CEST 2018


I am sorry that I did not clearly say in the cover letter that this patch set is
depending on another bug-fix patch set (http://patchwork.dpdk.org/cover/45611/)
we submitted. I will update the cover letter in next version.

They were in the same patch set and I separated them because one is dedicated to bug fixing.

Please check if this is the reason that you cannot apply.

Thanks
Yipeng

>-----Original Message-----
>From: Dharmik Thakkar [mailto:Dharmik.Thakkar at arm.com]
>Sent: Tuesday, October 2, 2018 1:53 PM
>To: Wang, Yipeng1 <yipeng1.wang at intel.com>
>Cc: Richardson, Bruce <bruce.richardson at intel.com>; Ananyev, Konstantin <konstantin.ananyev at intel.com>; dev at dpdk.org;
>Honnappa Nagarahalli <Honnappa.Nagarahalli at arm.com>; Gobriel, Sameh <sameh.gobriel at intel.com>
>Subject: Re: [dpdk-dev] [PATCH v5 4/4] hash: use partial-key hashing
>
>I am attempting to test the patch on an Arm machine, but it failed to apply.
>
>I’m getting the following error:
>
>error: patch failed: test/test/test_hash_perf.c:18
>error: test/test/test_hash_perf.c: patch does not apply
>Patch failed at 0003 test/hash: implement extendable bucket hash test
>
>> On Oct 1, 2018, at 1:35 PM, Yipeng Wang <yipeng1.wang at intel.com> wrote:
>>
>> This commit changes the hashing mechanism to "partial-key
>> hashing" to calculate bucket index and signature of key.
>>
>> This is  proposed in Bin Fan, et al's paper
>> "MemC3: Compact and Concurrent MemCache with Dumber Caching
>> and Smarter Hashing". Bascially the idea is to use "xor" to
>> derive alternative bucket from current bucket index and
>> signature.
>>
>> With "partial-key hashing", it reduces the bucket memory
>> requirement from two cache lines to one cache line, which
>> improves the memory efficiency and thus the lookup speed.
>>
>> Signed-off-by: Yipeng Wang <yipeng1.wang at intel.com>
>> Reviewed-by: Honnappa Nagarahalli <honnappa.nagarahalli at arm.com>
>> ---
>> lib/librte_hash/rte_cuckoo_hash.c | 246 +++++++++++++++++++-------------------
>> lib/librte_hash/rte_cuckoo_hash.h |   6 +-
>> lib/librte_hash/rte_hash.h        |   5 +-
>> 3 files changed, 131 insertions(+), 126 deletions(-)
>>
>> diff --git a/lib/librte_hash/rte_cuckoo_hash.c b/lib/librte_hash/rte_cuckoo_hash.c
>> index 133e181..3c7c9c5 100644
>> --- a/lib/librte_hash/rte_cuckoo_hash.c
>> +++ b/lib/librte_hash/rte_cuckoo_hash.c
>> @@ -90,6 +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)
>> {
>> @@ -327,9 +357,7 @@ rte_hash_create(const struct rte_hash_parameters *params)
>> 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
>> @@ -417,18 +445,6 @@ 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)
>> -{
>> -static const unsigned all_bits_shift = 12;
>> -static const unsigned alt_bits_xor = 0x5bd1e995;
>> -
>> -uint32_t tag = primary_hash >> all_bits_shift;
>> -
>> -return primary_hash ^ ((tag + 1) * alt_bits_xor);
>> -}
>> -
>> int32_t
>> rte_hash_count(const struct rte_hash *h)
>> {
>> @@ -560,14 +576,13 @@ enqueue_slot_back(const struct rte_hash *h,
>> /* 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, hash_sig_t sig, hash_sig_t alt_hash)
>> +struct rte_hash_bucket *bkt, uint16_t sig)
>> {
>> int i;
>> struct rte_hash_key *k, *keys = h->key_store;
>>
>> for (i = 0; i < RTE_HASH_BUCKET_ENTRIES; i++) {
>> -if (bkt->sig_current[i] == sig &&
>> -bkt->sig_alt[i] == alt_hash) {
>> +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) {
>> @@ -594,7 +609,7 @@ 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,
>> -hash_sig_t sig, hash_sig_t alt_hash, uint32_t new_idx,
>> +uint16_t sig, uint32_t new_idx,
>> int32_t *ret_val)
>> {
>> unsigned int i;
>> @@ -605,7 +620,7 @@ rte_hash_cuckoo_insert_mw(const struct rte_hash *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, alt_hash);
>> +ret = search_and_update(h, data, key, prim_bkt, sig);
>> if (ret != -1) {
>> __hash_rw_writer_unlock(h);
>> *ret_val = ret;
>> @@ -613,7 +628,7 @@ rte_hash_cuckoo_insert_mw(const struct rte_hash *h,
>> }
>>
>> FOR_EACH_BUCKET(cur_bkt, sec_bkt) {
>> -ret = search_and_update(h, data, key, cur_bkt, alt_hash, sig);
>> +ret = search_and_update(h, data, key, cur_bkt, sig);
>> if (ret != -1) {
>> __hash_rw_writer_unlock(h);
>> *ret_val = ret;
>> @@ -628,7 +643,6 @@ rte_hash_cuckoo_insert_mw(const struct rte_hash *h,
>> /* 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;
>> }
>> @@ -653,7 +667,7 @@ rte_hash_cuckoo_move_insert_mw(const struct rte_hash *h,
>> struct rte_hash_bucket *alt_bkt,
>> const struct rte_hash_key *key, void *data,
>> struct queue_node *leaf, uint32_t leaf_slot,
>> -hash_sig_t sig, hash_sig_t alt_hash, uint32_t new_idx,
>> +uint16_t sig, uint32_t new_idx,
>> int32_t *ret_val)
>> {
>> uint32_t prev_alt_bkt_idx;
>> @@ -674,7 +688,7 @@ rte_hash_cuckoo_move_insert_mw(const struct rte_hash *h,
>> /* Check if key was inserted after last check but before this
>>  * protected region.
>>  */
>> -ret = search_and_update(h, data, key, bkt, sig, alt_hash);
>> +ret = search_and_update(h, data, key, bkt, sig);
>> if (ret != -1) {
>> __hash_rw_writer_unlock(h);
>> *ret_val = ret;
>> @@ -682,7 +696,7 @@ rte_hash_cuckoo_move_insert_mw(const struct rte_hash *h,
>> }
>>
>> FOR_EACH_BUCKET(cur_bkt, alt_bkt) {
>> -ret = search_and_update(h, data, key, cur_bkt, alt_hash, sig);
>> +ret = search_and_update(h, data, key, cur_bkt, sig);
>> if (ret != -1) {
>> __hash_rw_writer_unlock(h);
>> *ret_val = ret;
>> @@ -695,8 +709,9 @@ rte_hash_cuckoo_move_insert_mw(const struct rte_hash *h,
>> prev_bkt = prev_node->bkt;
>> prev_slot = curr_node->prev_slot;
>>
>> -prev_alt_bkt_idx =
>> -prev_bkt->sig_alt[prev_slot] & h->bucket_bitmask;
>> +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)) {
>> @@ -710,10 +725,8 @@ rte_hash_cuckoo_move_insert_mw(const struct rte_hash *h,
>>  * Cuckoo insert to move elements back to its
>>  * primary bucket if available
>>  */
>> -curr_bkt->sig_alt[curr_slot] =
>> - prev_bkt->sig_current[prev_slot];
>> curr_bkt->sig_current[curr_slot] =
>> -prev_bkt->sig_alt[prev_slot];
>> +prev_bkt->sig_current[prev_slot];
>> curr_bkt->key_idx[curr_slot] =
>> prev_bkt->key_idx[prev_slot];
>>
>> @@ -723,7 +736,6 @@ rte_hash_cuckoo_move_insert_mw(const struct rte_hash *h,
>> }
>>
>> curr_bkt->sig_current[curr_slot] = sig;
>> -curr_bkt->sig_alt[curr_slot] = alt_hash;
>> curr_bkt->key_idx[curr_slot] = new_idx;
>>
>> __hash_rw_writer_unlock(h);
>> @@ -741,39 +753,44 @@ 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,
>> -hash_sig_t sig, hash_sig_t alt_hash,
>> +uint16_t sig, uint32_t bucket_idx,
>> uint32_t new_idx, int32_t *ret_val)
>> {
>> 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, alt_hash,
>> +tail, i, sig,
>> new_idx, ret_val);
>> if (likely(ret != -1))
>> return ret;
>> }
>>
>> /* Enqueue new node and keep prev node info */
>> -alt_bkt = &(h->buckets[curr_bkt->sig_alt[i]
>> -    & h->bucket_bitmask]);
>> +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++;
>> @@ -788,7 +805,7 @@ 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;
>> struct rte_hash_bucket *prim_bkt, *sec_bkt, *cur_bkt;
>> struct rte_hash_key *new_k, *keys = h->key_store;
>> @@ -803,18 +820,17 @@ __rte_hash_add_key_with_hash(const struct rte_hash *h, const void *key,
>> 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);
>>
>> /* Check if key is already inserted in primary location */
>> __hash_rw_writer_lock(h);
>> -ret = search_and_update(h, data, key, prim_bkt, sig, alt_hash);
>> +ret = search_and_update(h, data, key, prim_bkt, short_sig);
>> if (ret != -1) {
>> __hash_rw_writer_unlock(h);
>> return ret;
>> @@ -822,12 +838,13 @@ __rte_hash_add_key_with_hash(const struct rte_hash *h, const void *key,
>>
>> /* 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, alt_hash, sig);
>> +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 */
>> @@ -865,7 +882,7 @@ __rte_hash_add_key_with_hash(const struct rte_hash *h, const void *key,
>>
>> /* Find an empty slot and insert */
>> ret = rte_hash_cuckoo_insert_mw(h, prim_bkt, sec_bkt, key, data,
>> -sig, alt_hash, new_idx, &ret_val);
>> +short_sig, new_idx, &ret_val);
>> if (ret == 0)
>> return new_idx - 1;
>> else if (ret == 1) {
>> @@ -875,7 +892,7 @@ __rte_hash_add_key_with_hash(const struct rte_hash *h, const void *key,
>>
>> /* Primary bucket full, need to make space for new entry */
>> ret = rte_hash_cuckoo_make_space_mw(h, prim_bkt, sec_bkt, key, data,
>> -sig, alt_hash, new_idx, &ret_val);
>> +short_sig, prim_bucket_idx, new_idx, &ret_val);
>> if (ret == 0)
>> return new_idx - 1;
>> else if (ret == 1) {
>> @@ -885,7 +902,7 @@ __rte_hash_add_key_with_hash(const struct rte_hash *h, const void *key,
>>
>> /* Also search secondary bucket to get better occupancy */
>> ret = rte_hash_cuckoo_make_space_mw(h, sec_bkt, prim_bkt, key, data,
>> -alt_hash, sig, new_idx, &ret_val);
>> +short_sig, sec_bucket_idx, new_idx, &ret_val);
>>
>> if (ret == 0)
>> return new_idx - 1;
>> @@ -905,14 +922,14 @@ __rte_hash_add_key_with_hash(const struct rte_hash *h, const void *key,
>>  */
>> __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, sig, alt_hash);
>> +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;
>> }
>>
>> FOR_EACH_BUCKET(cur_bkt, sec_bkt) {
>> -ret = search_and_update(h, data, key, cur_bkt, alt_hash, sig);
>> +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;
>> @@ -924,8 +941,7 @@ __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(cur_bkt->key_idx[i] == EMPTY_SLOT)) {
>> -cur_bkt->sig_current[i] = alt_hash;
>> -cur_bkt->sig_alt[i] = sig;
>> +cur_bkt->sig_current[i] = short_sig;
>> cur_bkt->key_idx[i] = new_idx;
>> __hash_rw_writer_unlock(h);
>> return new_idx - 1;
>> @@ -943,8 +959,7 @@ __rte_hash_add_key_with_hash(const struct rte_hash *h, const void *key,
>>
>> 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] = alt_hash;
>> -(h->buckets_ext[bkt_id]).sig_alt[0] = sig;
>> +(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);
>> @@ -1003,7 +1018,7 @@ rte_hash_add_key_data(const struct rte_hash *h, const void *key, void *data)
>>
>> /* Search one bucket to find the match key */
>> static inline int32_t
>> -search_one_bucket(const struct rte_hash *h, const void *key, hash_sig_t sig,
>> +search_one_bucket(const struct rte_hash *h, const void *key, uint16_t sig,
>> void **data, const struct rte_hash_bucket *bkt)
>> {
>> int i;
>> @@ -1032,30 +1047,30 @@ 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 bucket_idx;
>> -hash_sig_t alt_hash;
>> +uint32_t prim_bucket_idx, sec_bucket_idx;
>> struct rte_hash_bucket *bkt, *cur_bkt;
>> int ret;
>> +uint16_t short_sig;
>>
>> -bucket_idx = sig & h->bucket_bitmask;
>> -bkt = &h->buckets[bucket_idx];
>> +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, sig, data, bkt);
>> +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_EACH_BUCKET(cur_bkt, bkt) {
>> -ret = search_one_bucket(h, key, alt_hash, data, cur_bkt);
>> +ret = search_one_bucket(h, key, short_sig, data, cur_bkt);
>> if (ret != -1) {
>> __hash_rw_reader_unlock(h);
>> return ret;
>> @@ -1102,7 +1117,6 @@ 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->multi_writer_support) {
>> lcore_id = rte_lcore_id();
>> cached_free_slots = &h->local_free_slots[lcore_id];
>> @@ -1141,9 +1155,7 @@ __rte_hash_compact_ll(struct rte_hash_bucket *cur_bkt, int pos) {
>> 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];
>> -cur_bkt->sig_alt[pos] = last_bkt->sig_alt[i];
>> last_bkt->sig_current[i] = NULL_SIGNATURE;
>> -last_bkt->sig_alt[i] = NULL_SIGNATURE;
>> last_bkt->key_idx[i] = EMPTY_SLOT;
>> return;
>> }
>> @@ -1153,7 +1165,7 @@ __rte_hash_compact_ll(struct rte_hash_bucket *cur_bkt, int pos) {
>> /* Search one bucket and remove the matched key */
>> static inline int32_t
>> search_and_remove(const struct rte_hash *h, const void *key,
>> -struct rte_hash_bucket *bkt, hash_sig_t sig, int *pos)
>> +struct rte_hash_bucket *bkt, uint16_t sig, int *pos)
>> {
>> struct rte_hash_key *k, *keys = h->key_store;
>> unsigned int i;
>> @@ -1185,19 +1197,21 @@ static inline int32_t
>> __rte_hash_del_key_with_hash(const struct rte_hash *h, const void *key,
>> hash_sig_t sig)
>> {
>> -uint32_t bucket_idx;
>> -hash_sig_t alt_hash;
>> +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;
>>
>> -bucket_idx = sig & h->bucket_bitmask;
>> -prim_bkt = &h->buckets[bucket_idx];
>> +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];
>>
>> __hash_rw_writer_lock(h);
>> /* look for key in primary bucket */
>> -ret = search_and_remove(h, key, prim_bkt, sig, &pos);
>> +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;
>> @@ -1206,12 +1220,10 @@ __rte_hash_del_key_with_hash(const struct rte_hash *h, const void *key,
>> }
>>
>> /* Calculate secondary hash */
>> -alt_hash = rte_hash_secondary_hash(sig);
>> -bucket_idx = alt_hash & h->bucket_bitmask;
>> -sec_bkt = &h->buckets[bucket_idx];
>> +sec_bkt = &h->buckets[sec_bucket_idx];
>>
>> FOR_EACH_BUCKET(cur_bkt, sec_bkt) {
>> -ret = search_and_remove(h, key, cur_bkt, alt_hash, &pos);
>> +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;
>> @@ -1288,55 +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
>> @@ -1349,7 +1341,9 @@ __rte_hash_lookup_bulk(const struct rte_hash *h, const void **keys,
>> 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};
>> @@ -1368,10 +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]);
>> @@ -1380,10 +1377,13 @@ __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]);
>> @@ -1394,10 +1394,11 @@ __rte_hash_lookup_bulk(const struct rte_hash *h, const void **keys,
>> 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 *)(
>> @@ -1408,7 +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 *)(
>> @@ -1422,7 +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 =
>> @@ -1441,11 +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 =
>> @@ -1465,7 +1469,7 @@ __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:
>> @@ -1488,10 +1492,10 @@ __rte_hash_lookup_bulk(const struct rte_hash *h, const void **keys,
>> FOR_EACH_BUCKET(cur_bkt, next_bkt) {
>> if (data != NULL)
>> ret = search_one_bucket(h, keys[i],
>> -sec_hash[i], &data[i], cur_bkt);
>> +sig[i], &data[i], cur_bkt);
>> else
>> ret = search_one_bucket(h, keys[i],
>> -sec_hash[i], NULL, cur_bkt);
>> +sig[i], NULL, cur_bkt);
>> if (ret != -1) {
>> positions[i] = ret;
>> hits |= 1ULL << i;
>> diff --git a/lib/librte_hash/rte_cuckoo_hash.h b/lib/librte_hash/rte_cuckoo_hash.h
>> index e601520..7753cd8 100644
>> --- a/lib/librte_hash/rte_cuckoo_hash.h
>> +++ b/lib/librte_hash/rte_cuckoo_hash.h
>> @@ -129,18 +129,15 @@ struct rte_hash_key {
>> enum rte_hash_sig_compare_function {
>> RTE_HASH_COMPARE_SCALAR = 0,
>> RTE_HASH_COMPARE_SSE,
>> -RTE_HASH_COMPARE_AVX2,
>> RTE_HASH_COMPARE_NUM
>> };
>>
>> /** Bucket structure */
>> struct rte_hash_bucket {
>> -hash_sig_t sig_current[RTE_HASH_BUCKET_ENTRIES];
>> +uint16_t sig_current[RTE_HASH_BUCKET_ENTRIES];
>>
>> uint32_t key_idx[RTE_HASH_BUCKET_ENTRIES];
>>
>> -hash_sig_t sig_alt[RTE_HASH_BUCKET_ENTRIES];
>> -
>> uint8_t flag[RTE_HASH_BUCKET_ENTRIES];
>>
>> void *next;
>> @@ -193,6 +190,7 @@ struct rte_hash {
>>
>> struct queue_node {
>> struct rte_hash_bucket *bkt; /* Current bucket on the bfs search */
>> +uint32_t cur_bkt_idx;
>>
>> struct queue_node *prev;     /* Parent(bucket) in search path */
>> int prev_slot;               /* Parent(slot) in search path */
>> diff --git a/lib/librte_hash/rte_hash.h b/lib/librte_hash/rte_hash.h
>> index 11d8e28..6ace64e 100644
>> --- a/lib/librte_hash/rte_hash.h
>> +++ b/lib/librte_hash/rte_hash.h
>> @@ -40,7 +40,10 @@ extern "C" {
>> /** Flag to indicate the extendabe bucket table feature should be used */
>> #define RTE_HASH_EXTRA_FLAGS_EXT_TABLE 0x08
>>
>> -/** Signature of key that is stored internally. */
>> +/**
>> + * The type of hash value of a key.
>> + * It should be a value of at least 32bit with fully random pattern.
>> + */
>> typedef uint32_t hash_sig_t;
>>
>> /** Type of function that can be used for calculating the hash value. */
>> --
>> 2.7.4
>>
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