From: Yipeng Wang Date: Wed, 4 Oct 2017 03:12:21 +0000 (-0700) Subject: member: implement vBF mode X-Git-Tag: spdx-start~1698 X-Git-Url: http://git.droids-corp.org/?a=commitdiff_plain;h=54b8edc07c5572c97124efb4227aff52b66b9a5f;p=dpdk.git member: implement vBF mode Bloom Filter (BF) [1] is a well-known space-efficient probabilistic data structure that answers set membership queries. Vector of Bloom Filters (vBF) is an extension to traditional BF that supports multi-set membership testing. Traditional BF will return found or not-found for each key. vBF will also return which set the key belongs to if it is found. Since each set requires a BF, vBF should be used when set count is small. vBF's false positive rate could be set appropriately so that its memory requirement and lookup speed is better in certain cases comparing to HT based set-summary. This patch adds the vBF implementation. [1]B H Bloom, “Space/Time Trade-offs in Hash Coding with Allowable Errors,” Communications of the ACM, 1970. Signed-off-by: Yipeng Wang Reviewed-by: Pablo de Lara --- diff --git a/lib/librte_member/Makefile b/lib/librte_member/Makefile index 434f74531e..3bac1d0abd 100644 --- a/lib/librte_member/Makefile +++ b/lib/librte_member/Makefile @@ -44,7 +44,7 @@ EXPORT_MAP := rte_member_version.map LIBABIVER := 1 # all source are stored in SRCS-y -SRCS-$(CONFIG_RTE_LIBRTE_MEMBER) += rte_member.c rte_member_ht.c +SRCS-$(CONFIG_RTE_LIBRTE_MEMBER) += rte_member.c rte_member_ht.c rte_member_vbf.c # install includes SYMLINK-$(CONFIG_RTE_LIBRTE_MEMBER)-include := rte_member.h diff --git a/lib/librte_member/rte_member.c b/lib/librte_member/rte_member.c index 7e74e1835f..b9def9a575 100644 --- a/lib/librte_member/rte_member.c +++ b/lib/librte_member/rte_member.c @@ -42,6 +42,7 @@ #include "rte_member.h" #include "rte_member_ht.h" +#include "rte_member_vbf.h" int librte_member_logtype; @@ -100,6 +101,9 @@ rte_member_free(struct rte_member_setsum *setsum) case RTE_MEMBER_TYPE_HT: rte_member_free_ht(setsum); break; + case RTE_MEMBER_TYPE_VBF: + rte_member_free_vbf(setsum); + break; default: break; } @@ -170,6 +174,9 @@ rte_member_create(const struct rte_member_parameters *params) case RTE_MEMBER_TYPE_HT: ret = rte_member_create_ht(setsum, params); break; + case RTE_MEMBER_TYPE_VBF: + ret = rte_member_create_vbf(setsum, params); + break; default: goto error_unlock_exit; } @@ -200,6 +207,8 @@ rte_member_add(const struct rte_member_setsum *setsum, const void *key, switch (setsum->type) { case RTE_MEMBER_TYPE_HT: return rte_member_add_ht(setsum, key, set_id); + case RTE_MEMBER_TYPE_VBF: + return rte_member_add_vbf(setsum, key, set_id); default: return -EINVAL; } @@ -215,6 +224,8 @@ rte_member_lookup(const struct rte_member_setsum *setsum, const void *key, switch (setsum->type) { case RTE_MEMBER_TYPE_HT: return rte_member_lookup_ht(setsum, key, set_id); + case RTE_MEMBER_TYPE_VBF: + return rte_member_lookup_vbf(setsum, key, set_id); default: return -EINVAL; } @@ -232,6 +243,9 @@ rte_member_lookup_bulk(const struct rte_member_setsum *setsum, case RTE_MEMBER_TYPE_HT: return rte_member_lookup_bulk_ht(setsum, keys, num_keys, set_ids); + case RTE_MEMBER_TYPE_VBF: + return rte_member_lookup_bulk_vbf(setsum, keys, num_keys, + set_ids); default: return -EINVAL; } @@ -248,6 +262,9 @@ rte_member_lookup_multi(const struct rte_member_setsum *setsum, const void *key, case RTE_MEMBER_TYPE_HT: return rte_member_lookup_multi_ht(setsum, key, match_per_key, set_id); + case RTE_MEMBER_TYPE_VBF: + return rte_member_lookup_multi_vbf(setsum, key, match_per_key, + set_id); default: return -EINVAL; } @@ -267,6 +284,9 @@ rte_member_lookup_multi_bulk(const struct rte_member_setsum *setsum, case RTE_MEMBER_TYPE_HT: return rte_member_lookup_multi_bulk_ht(setsum, keys, num_keys, max_match_per_key, match_count, set_ids); + case RTE_MEMBER_TYPE_VBF: + return rte_member_lookup_multi_bulk_vbf(setsum, keys, num_keys, + max_match_per_key, match_count, set_ids); default: return -EINVAL; } @@ -282,6 +302,8 @@ rte_member_delete(const struct rte_member_setsum *setsum, const void *key, switch (setsum->type) { case RTE_MEMBER_TYPE_HT: return rte_member_delete_ht(setsum, key, set_id); + /* current vBF implementation does not support delete function */ + case RTE_MEMBER_TYPE_VBF: default: return -EINVAL; } @@ -296,6 +318,9 @@ rte_member_reset(const struct rte_member_setsum *setsum) case RTE_MEMBER_TYPE_HT: rte_member_reset_ht(setsum); return; + case RTE_MEMBER_TYPE_VBF: + rte_member_reset_vbf(setsum); + return; default: return; } diff --git a/lib/librte_member/rte_member.h b/lib/librte_member/rte_member.h index 8f24296ead..b7213cd419 100644 --- a/lib/librte_member/rte_member.h +++ b/lib/librte_member/rte_member.h @@ -127,6 +127,7 @@ struct rte_member_parameters; */ enum rte_member_setsum_type { RTE_MEMBER_TYPE_HT = 0, /**< Hash table based set summary. */ + RTE_MEMBER_TYPE_VBF, /**< Vector of bloom filters. */ RTE_MEMBER_NUM_TYPE }; diff --git a/lib/librte_member/rte_member_vbf.c b/lib/librte_member/rte_member_vbf.c new file mode 100644 index 0000000000..1a98ac84c8 --- /dev/null +++ b/lib/librte_member/rte_member_vbf.c @@ -0,0 +1,350 @@ +/*- + * BSD LICENSE + * + * Copyright(c) 2017 Intel Corporation. All rights reserved. + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * * Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * * Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in + * the documentation and/or other materials provided with the + * distribution. + * * Neither the name of Intel Corporation nor the names of its + * contributors may be used to endorse or promote products derived + * from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ + +#include +#include + +#include +#include +#include +#include + +#include "rte_member.h" +#include "rte_member_vbf.h" + +/* + * vBF currently implemented as a big array. + * The BFs have a vertical layout. Bits in same location of all bfs will stay + * in the same cache line. + * For example, if we have 32 bloom filters, we use a uint32_t array to + * represent all of them. array[0] represent the first location of all the + * bloom filters, array[1] represents the second location of all the + * bloom filters, etc. The advantage of this layout is to minimize the average + * number of memory accesses to test all bloom filters. + * + * Currently the implementation supports vBF containing 1,2,4,8,16,32 BFs. + */ +int +rte_member_create_vbf(struct rte_member_setsum *ss, + const struct rte_member_parameters *params) +{ + + if (params->num_set > RTE_MEMBER_MAX_BF || + !rte_is_power_of_2(params->num_set) || + params->num_keys == 0 || + params->false_positive_rate == 0 || + params->false_positive_rate > 1) { + rte_errno = EINVAL; + RTE_MEMBER_LOG(ERR, "Membership vBF create with invalid parameters\n"); + return -EINVAL; + } + + /* We assume expected keys evenly distribute to all BFs */ + uint32_t num_keys_per_bf = 1 + (params->num_keys - 1) / ss->num_set; + + /* + * Note that the false positive rate is for all BFs in the vBF + * such that the single BF's false positive rate needs to be + * calculated. + * Assume each BF's False positive rate is fp_one_bf. The total false + * positive rate is fp = 1-(1-fp_one_bf)^n. + * => fp_one_bf = 1 - (1-fp)^(1/n) + */ + + float fp_one_bf = 1 - pow((1 - params->false_positive_rate), + 1.0 / ss->num_set); + + if (fp_one_bf == 0) { + rte_errno = EINVAL; + RTE_MEMBER_LOG(ERR, "Membership BF false positive rate is too small\n"); + return -EINVAL; + } + + uint32_t bits = ceil((num_keys_per_bf * + log(fp_one_bf)) / + log(1.0 / (pow(2.0, log(2.0))))); + + /* We round to power of 2 for performance during lookup */ + ss->bits = rte_align32pow2(bits); + + ss->num_hashes = (uint32_t)(log(2.0) * bits / num_keys_per_bf); + ss->bit_mask = ss->bits - 1; + + /* + * Since we round the bits to power of 2, the final false positive + * rate will probably not be same as the user specified. We log the + * new value as debug message. + */ + float new_fp = pow((1 - pow((1 - 1.0 / ss->bits), num_keys_per_bf * + ss->num_hashes)), ss->num_hashes); + new_fp = 1 - pow((1 - new_fp), ss->num_set); + + /* + * Reduce hash function count, until we approach the user specified + * false-positive rate. Otherwise it is too conservative + */ + int tmp_num_hash = ss->num_hashes; + + while (tmp_num_hash > 1) { + float tmp_fp = new_fp; + + tmp_num_hash--; + new_fp = pow((1 - pow((1 - 1.0 / ss->bits), num_keys_per_bf * + tmp_num_hash)), tmp_num_hash); + new_fp = 1 - pow((1 - new_fp), ss->num_set); + + if (new_fp > params->false_positive_rate) { + new_fp = tmp_fp; + tmp_num_hash++; + break; + } + } + + ss->num_hashes = tmp_num_hash; + + /* + * To avoid multiplication and division: + * mul_shift is used for multiplication shift during bit test + * div_shift is used for division shift, to be divided by number of bits + * represented by a uint32_t variable + */ + ss->mul_shift = __builtin_ctzl(ss->num_set); + ss->div_shift = __builtin_ctzl(32 >> ss->mul_shift); + + RTE_MEMBER_LOG(DEBUG, "vector bloom filter created, " + "each bloom filter expects %u keys, needs %u bits, %u hashes, " + "with false positive rate set as %.5f, " + "The new calculated vBF false positive rate is %.5f\n", + num_keys_per_bf, ss->bits, ss->num_hashes, fp_one_bf, new_fp); + + ss->table = rte_zmalloc_socket(NULL, ss->num_set * (ss->bits >> 3), + RTE_CACHE_LINE_SIZE, ss->socket_id); + if (ss->table == NULL) + return -ENOMEM; + + return 0; +} + +static inline uint32_t +test_bit(uint32_t bit_loc, const struct rte_member_setsum *ss) +{ + uint32_t *vbf = ss->table; + uint32_t n = ss->num_set; + uint32_t div_shift = ss->div_shift; + uint32_t mul_shift = ss->mul_shift; + /* + * a is how many bits in one BF are represented by one 32bit + * variable. + */ + uint32_t a = 32 >> mul_shift; + /* + * x>>b is the divide, x & (a-1) is the mod, & (1<> div_shift] >> + ((bit_loc & (a - 1)) << mul_shift)) & ((1ULL << n) - 1); +} + +static inline void +set_bit(uint32_t bit_loc, const struct rte_member_setsum *ss, int32_t set) +{ + uint32_t *vbf = ss->table; + uint32_t div_shift = ss->div_shift; + uint32_t mul_shift = ss->mul_shift; + uint32_t a = 32 >> mul_shift; + + vbf[bit_loc >> div_shift] |= + 1UL << (((bit_loc & (a - 1)) << mul_shift) + set - 1); +} + +int +rte_member_lookup_vbf(const struct rte_member_setsum *ss, const void *key, + member_set_t *set_id) +{ + uint32_t j; + uint32_t h1 = MEMBER_HASH_FUNC(key, ss->key_len, ss->prim_hash_seed); + uint32_t h2 = MEMBER_HASH_FUNC(&h1, sizeof(uint32_t), + ss->sec_hash_seed); + uint32_t mask = ~0; + uint32_t bit_loc; + + for (j = 0; j < ss->num_hashes; j++) { + bit_loc = (h1 + j * h2) & ss->bit_mask; + mask &= test_bit(bit_loc, ss); + } + + if (mask) { + *set_id = __builtin_ctzl(mask) + 1; + return 1; + } + + *set_id = RTE_MEMBER_NO_MATCH; + return 0; +} + +uint32_t +rte_member_lookup_bulk_vbf(const struct rte_member_setsum *ss, + const void **keys, uint32_t num_keys, member_set_t *set_ids) +{ + uint32_t i, k; + uint32_t num_matches = 0; + uint32_t mask[RTE_MEMBER_LOOKUP_BULK_MAX]; + uint32_t h1[RTE_MEMBER_LOOKUP_BULK_MAX], h2[RTE_MEMBER_LOOKUP_BULK_MAX]; + uint32_t bit_loc; + + for (i = 0; i < num_keys; i++) + h1[i] = MEMBER_HASH_FUNC(keys[i], ss->key_len, + ss->prim_hash_seed); + for (i = 0; i < num_keys; i++) + h2[i] = MEMBER_HASH_FUNC(&h1[i], sizeof(uint32_t), + ss->sec_hash_seed); + for (i = 0; i < num_keys; i++) { + mask[i] = ~0; + for (k = 0; k < ss->num_hashes; k++) { + bit_loc = (h1[i] + k * h2[i]) & ss->bit_mask; + mask[i] &= test_bit(bit_loc, ss); + } + } + for (i = 0; i < num_keys; i++) { + if (mask[i]) { + set_ids[i] = __builtin_ctzl(mask[i]) + 1; + num_matches++; + } else + set_ids[i] = RTE_MEMBER_NO_MATCH; + } + return num_matches; +} + +uint32_t +rte_member_lookup_multi_vbf(const struct rte_member_setsum *ss, + const void *key, uint32_t match_per_key, + member_set_t *set_id) +{ + uint32_t num_matches = 0; + uint32_t j; + uint32_t h1 = MEMBER_HASH_FUNC(key, ss->key_len, ss->prim_hash_seed); + uint32_t h2 = MEMBER_HASH_FUNC(&h1, sizeof(uint32_t), + ss->sec_hash_seed); + uint32_t mask = ~0; + uint32_t bit_loc; + + for (j = 0; j < ss->num_hashes; j++) { + bit_loc = (h1 + j * h2) & ss->bit_mask; + mask &= test_bit(bit_loc, ss); + } + while (mask) { + uint32_t loc = __builtin_ctzl(mask); + set_id[num_matches] = loc + 1; + num_matches++; + if (num_matches >= match_per_key) + return num_matches; + mask &= ~(1UL << loc); + } + return num_matches; +} + +uint32_t +rte_member_lookup_multi_bulk_vbf(const struct rte_member_setsum *ss, + const void **keys, uint32_t num_keys, uint32_t match_per_key, + uint32_t *match_count, + member_set_t *set_ids) +{ + uint32_t i, k; + uint32_t num_matches = 0; + uint32_t match_cnt_t; + uint32_t mask[RTE_MEMBER_LOOKUP_BULK_MAX]; + uint32_t h1[RTE_MEMBER_LOOKUP_BULK_MAX], h2[RTE_MEMBER_LOOKUP_BULK_MAX]; + uint32_t bit_loc; + + for (i = 0; i < num_keys; i++) + h1[i] = MEMBER_HASH_FUNC(keys[i], ss->key_len, + ss->prim_hash_seed); + for (i = 0; i < num_keys; i++) + h2[i] = MEMBER_HASH_FUNC(&h1[i], sizeof(uint32_t), + ss->sec_hash_seed); + for (i = 0; i < num_keys; i++) { + mask[i] = ~0; + for (k = 0; k < ss->num_hashes; k++) { + bit_loc = (h1[i] + k * h2[i]) & ss->bit_mask; + mask[i] &= test_bit(bit_loc, ss); + } + } + for (i = 0; i < num_keys; i++) { + match_cnt_t = 0; + while (mask[i]) { + uint32_t loc = __builtin_ctzl(mask[i]); + set_ids[i * match_per_key + match_cnt_t] = loc + 1; + match_cnt_t++; + if (match_cnt_t >= match_per_key) + break; + mask[i] &= ~(1UL << loc); + } + match_count[i] = match_cnt_t; + if (match_cnt_t != 0) + num_matches++; + } + return num_matches; +} + +int +rte_member_add_vbf(const struct rte_member_setsum *ss, + const void *key, member_set_t set_id) +{ + uint32_t i, h1, h2; + uint32_t bit_loc; + + if (set_id > ss->num_set || set_id == RTE_MEMBER_NO_MATCH) + return -EINVAL; + + h1 = MEMBER_HASH_FUNC(key, ss->key_len, ss->prim_hash_seed); + h2 = MEMBER_HASH_FUNC(&h1, sizeof(uint32_t), ss->sec_hash_seed); + + for (i = 0; i < ss->num_hashes; i++) { + bit_loc = (h1 + i * h2) & ss->bit_mask; + set_bit(bit_loc, ss, set_id); + } + return 0; +} + +void +rte_member_free_vbf(struct rte_member_setsum *ss) +{ + rte_free(ss->table); +} + +void +rte_member_reset_vbf(const struct rte_member_setsum *ss) +{ + uint32_t *vbf = ss->table; + memset(vbf, 0, (ss->num_set * ss->bits) >> 3); +} diff --git a/lib/librte_member/rte_member_vbf.h b/lib/librte_member/rte_member_vbf.h new file mode 100644 index 0000000000..5bc158b9e4 --- /dev/null +++ b/lib/librte_member/rte_member_vbf.h @@ -0,0 +1,82 @@ +/*- + * BSD LICENSE + * + * Copyright(c) 2017 Intel Corporation. All rights reserved. + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * * Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * * Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in + * the documentation and/or other materials provided with the + * distribution. + * * Neither the name of Intel Corporation nor the names of its + * contributors may be used to endorse or promote products derived + * from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ + +#ifndef _RTE_MEMBER_VBF_H_ +#define _RTE_MEMBER_VBF_H_ + +#ifdef __cplusplus +extern "C" { +#endif + +/* Currently we only support up to 32 sets in vBF */ +#define RTE_MEMBER_MAX_BF 32 + +int +rte_member_create_vbf(struct rte_member_setsum *ss, + const struct rte_member_parameters *params); + +int +rte_member_lookup_vbf(const struct rte_member_setsum *setsum, + const void *key, member_set_t *set_id); + +uint32_t +rte_member_lookup_bulk_vbf(const struct rte_member_setsum *setsum, + const void **keys, uint32_t num_keys, + member_set_t *set_ids); + +uint32_t +rte_member_lookup_multi_vbf(const struct rte_member_setsum *setsum, + const void *key, uint32_t match_per_key, + member_set_t *set_id); + +uint32_t +rte_member_lookup_multi_bulk_vbf(const struct rte_member_setsum *setsum, + const void **keys, uint32_t num_keys, uint32_t match_per_key, + uint32_t *match_count, + member_set_t *set_ids); + +int +rte_member_add_vbf(const struct rte_member_setsum *setsum, + const void *key, member_set_t set_id); + +void +rte_member_free_vbf(struct rte_member_setsum *ss); + +void +rte_member_reset_vbf(const struct rte_member_setsum *setsum); + +#ifdef __cplusplus +} +#endif + +#endif /* _RTE_MEMBER_VBF_H_ */