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Diffstat (limited to 'lib/librte_member/rte_member.h')
| -rw-r--r-- | lib/librte_member/rte_member.h | 513 |
1 files changed, 513 insertions, 0 deletions
diff --git a/lib/librte_member/rte_member.h b/lib/librte_member/rte_member.h new file mode 100644 index 00000000..9b0c8f99 --- /dev/null +++ b/lib/librte_member/rte_member.h @@ -0,0 +1,513 @@ +/*- + * 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. + */ + +/** + * @file + * + * RTE Membership Library + * + * The Membership Library is an extension and generalization of a traditional + * filter (for example Bloom Filter and cuckoo filter) structure that has + * multiple usages in a variety of workloads and applications. The library is + * used to test if a key belongs to certain sets. Two types of such + * "set-summary" structures are implemented: hash-table based (HT) and vector + * bloom filter (vBF). For HT setsummary, two subtypes or modes are available, + * cache and non-cache modes. The table below summarize some properties of + * the different implementations. + * + * @warning + * @b EXPERIMENTAL: this API may change without prior notice + */ + +/** + * <!-- + * +==========+=====================+================+=========================+ + * | type | vbf | HT-cache | HT-non-cache | + * +==========+=====================+==========================================+ + * |structure | bloom-filter array | hash-table like without storing key | + * +----------+---------------------+------------------------------------------+ + * |set id | limited by bf count | [1, 0x7fff] | + * | | up to 32. | | + * +----------+---------------------+------------------------------------------+ + * |usages & | small set range, | can delete, | cache most recent keys, | + * |properties| user-specified | big set range, | have both false-positive| + * | | false-positive rate,| small false | and false-negative | + * | | no deletion support.| positive depend| depend on table size, | + * | | | on table size, | automatic overwritten. | + * | | | new key does | | + * | | | not overwrite | | + * | | | existing key. | | + * +----------+---------------------+----------------+-------------------------+ + * --> + */ + +#ifndef _RTE_MEMBER_H_ +#define _RTE_MEMBER_H_ + +#ifdef __cplusplus +extern "C" { +#endif + +#include <stdint.h> + +/** The set ID type that stored internally in hash table based set summary. */ +typedef uint16_t member_set_t; +/** Invalid set ID used to mean no match found. */ +#define RTE_MEMBER_NO_MATCH 0 +/** Maximum size of hash table that can be created. */ +#define RTE_MEMBER_ENTRIES_MAX (1 << 30) +/** Maximum number of keys that can be searched as a bulk */ +#define RTE_MEMBER_LOOKUP_BULK_MAX 64 +/** Entry count per bucket in hash table based mode. */ +#define RTE_MEMBER_BUCKET_ENTRIES 16 +/** Maximum number of characters in setsum name. */ +#define RTE_MEMBER_NAMESIZE 32 + +/** @internal Hash function used by membership library. */ +#if defined(RTE_ARCH_X86) || defined(RTE_MACHINE_CPUFLAG_CRC32) +#include <rte_hash_crc.h> +#define MEMBER_HASH_FUNC rte_hash_crc +#else +#include <rte_jhash.h> +#define MEMBER_HASH_FUNC rte_jhash +#endif + +extern int librte_member_logtype; + +#define RTE_MEMBER_LOG(level, fmt, args...) \ +rte_log(RTE_LOG_ ## level, librte_member_logtype, "%s(): " fmt, \ + __func__, ## args) + +/** @internal setsummary structure. */ +struct rte_member_setsum; + +/** + * @warning + * @b EXPERIMENTAL: this API may change without prior notice + * + * Parameter struct used to create set summary + */ +struct rte_member_parameters; + +/** + * @warning + * @b EXPERIMENTAL: this API may change without prior notice + * + * Define different set summary types + */ +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 +}; + +/** @internal compare function for different arch. */ +enum rte_member_sig_compare_function { + RTE_MEMBER_COMPARE_SCALAR = 0, + RTE_MEMBER_COMPARE_AVX2, + RTE_MEMBER_COMPARE_NUM +}; + +/** @internal setsummary structure. */ +struct rte_member_setsum { + enum rte_member_setsum_type type; /* Type of the set summary. */ + uint32_t key_len; /* Length of key. */ + uint32_t prim_hash_seed; /* Primary hash function seed. */ + uint32_t sec_hash_seed; /* Secondary hash function seed. */ + + /* Hash table based. */ + uint32_t bucket_cnt; /* Number of buckets. */ + uint32_t bucket_mask; /* Bit mask to get bucket index. */ + /* For runtime selecting AVX, scalar, etc for signature comparison. */ + enum rte_member_sig_compare_function sig_cmp_fn; + uint8_t cache; /* If it is cache mode for ht based. */ + + /* Vector bloom filter. */ + uint32_t num_set; /* Number of set (bf) in vbf. */ + uint32_t bits; /* Number of bits in each bf. */ + uint32_t bit_mask; /* Bit mask to get bit location in bf. */ + uint32_t num_hashes; /* Number of hash values to index bf. */ + + uint32_t mul_shift; /* vbf internal variable used during bit test. */ + uint32_t div_shift; /* vbf internal variable used during bit test. */ + + void *table; /* This is the handler of hash table or vBF array. */ + + + /* Second cache line should start here. */ + uint32_t socket_id; /* NUMA Socket ID for memory. */ + char name[RTE_MEMBER_NAMESIZE]; /* Name of this set summary. */ +} __rte_cache_aligned; + +/** + * @warning + * @b EXPERIMENTAL: this API may change without prior notice + * + * Parameters used when create the set summary table. Currently user can + * specify two types of setsummary: HT based and vBF. For HT based, user can + * specify cache or non-cache mode. Here is a table to describe some differences + * + */ +struct rte_member_parameters { + const char *name; /**< Name of the hash. */ + + /** + * User to specify the type of the setsummary from one of + * rte_member_setsum_type. + * + * HT based setsummary is implemented like a hash table. User should use + * this type when there are many sets. + * + * vBF setsummary is a vector of bloom filters. It is used when number + * of sets is not big (less than 32 for current implementation). + */ + enum rte_member_setsum_type type; + + /** + * is_cache is only used for HT based setsummary. + * + * If it is HT based setsummary, user to specify the subtype or mode + * of the setsummary. It could be cache, or non-cache mode. + * Set is_cache to be 1 if to use as cache mode. + * + * For cache mode, keys can be evicted out of the HT setsummary. Keys + * with the same signature and map to the same bucket + * will overwrite each other in the setsummary table. + * This mode is useful for the case that the set-summary only + * needs to keep record of the recently inserted keys. Both + * false-negative and false-positive could happen. + * + * For non-cache mode, keys cannot be evicted out of the cache. So for + * this mode the setsummary will become full eventually. Keys with the + * same signature but map to the same bucket will still occupy multiple + * entries. This mode does not give false-negative result. + */ + uint8_t is_cache; + + /** + * For HT setsummary, num_keys equals to the number of entries of the + * table. When the number of keys inserted in the HT setsummary + * approaches this number, eviction could happen. For cache mode, + * keys could be evicted out of the table. For non-cache mode, keys will + * be evicted to other buckets like cuckoo hash. The table will also + * likely to become full before the number of inserted keys equal to the + * total number of entries. + * + * For vBF, num_keys equal to the expected number of keys that will + * be inserted into the vBF. The implementation assumes the keys are + * evenly distributed to each BF in vBF. This is used to calculate the + * number of bits we need for each BF. User does not specify the size of + * each BF directly because the optimal size depends on the num_keys + * and false positive rate. + */ + uint32_t num_keys; + + /** + * The length of key is used for hash calculation. Since key is not + * stored in set-summary, large key does not require more memory space. + */ + uint32_t key_len; + + /** + * num_set is only used for vBF, but not used for HT setsummary. + * + * num_set is equal to the number of BFs in vBF. For current + * implementation, it only supports 1,2,4,8,16,32 BFs in one vBF set + * summary. If other number of sets are needed, for example 5, the user + * should allocate the minimum available value that larger than 5, + * which is 8. + */ + uint32_t num_set; + + /** + * false_positive_rate is only used for vBF, but not used for HT + * setsummary. + * + * For vBF, false_positive_rate is the user-defined false positive rate + * given expected number of inserted keys (num_keys). It is used to + * calculate the total number of bits for each BF, and the number of + * hash values used during lookup and insertion. For details please + * refer to vBF implementation and membership library documentation. + * + * For HT, This parameter is not directly set by users. + * HT setsummary's false positive rate is in the order of: + * false_pos = (1/bucket_count)*(1/2^16), since we use 16-bit signature. + * This is because two keys needs to map to same bucket and same + * signature to have a collision (false positive). bucket_count is equal + * to number of entries (num_keys) divided by entry count per bucket + * (RTE_MEMBER_BUCKET_ENTRIES). Thus, the false_positive_rate is not + * directly set by users for HT mode. + */ + float false_positive_rate; + + /** + * We use two seeds to calculate two independent hashes for each key. + * + * For HT type, one hash is used as signature, and the other is used + * for bucket location. + * For vBF type, these two hashes and their combinations are used as + * hash locations to index the bit array. + */ + uint32_t prim_hash_seed; + + /** + * The secondary seed should be a different value from the primary seed. + */ + uint32_t sec_hash_seed; + + int socket_id; /**< NUMA Socket ID for memory. */ +}; + +/** + * @warning + * @b EXPERIMENTAL: this API may change without prior notice + * + * Find an existing set-summary and return a pointer to it. + * + * @param name + * Name of the set-summary. + * @return + * Pointer to the set-summary or NULL if object not found + * with rte_errno set appropriately. Possible rte_errno values include: + * - ENOENT - value not available for return + */ +struct rte_member_setsum * +rte_member_find_existing(const char *name); + +/** + * @warning + * @b EXPERIMENTAL: this API may change without prior notice + * + * Create set-summary (SS). + * + * @param params + * Parameters to initialize the setsummary. + * @return + * Return the pointer to the setsummary. + * Return value is NULL if the creation failed. + */ +struct rte_member_setsum * +rte_member_create(const struct rte_member_parameters *params); + +/** + * @warning + * @b EXPERIMENTAL: this API may change without prior notice + * + * Lookup key in set-summary (SS). + * Single key lookup and return as soon as the first match found + * + * @param setsum + * Pointer of a setsummary. + * @param key + * Pointer of the key to be looked up. + * @param set_id + * Output the set id matches the key. + * @return + * Return 1 for found a match and 0 for not found a match. + */ +int +rte_member_lookup(const struct rte_member_setsum *setsum, const void *key, + member_set_t *set_id); + +/** + * @warning + * @b EXPERIMENTAL: this API may change without prior notice + * + * Lookup bulk of keys in set-summary (SS). + * Each key lookup returns as soon as the first match found + * + * @param setsum + * Pointer of a setsummary. + * @param keys + * Pointer of the bulk of keys to be looked up. + * @param num_keys + * Number of keys that will be lookup. + * @param set_ids + * Output set ids for all the keys to this array. + * User should preallocate array that can contain all results, which size is + * the num_keys. + * @return + * The number of keys that found a match. + */ +int +rte_member_lookup_bulk(const struct rte_member_setsum *setsum, + const void **keys, uint32_t num_keys, + member_set_t *set_ids); + +/** + * @warning + * @b EXPERIMENTAL: this API may change without prior notice + * + * Lookup a key in set-summary (SS) for multiple matches. + * The key lookup will find all matched entries (multiple match). + * Note that for cache mode of HT, each key can have at most one match. This is + * because keys with same signature that maps to same bucket will overwrite + * each other. So multi-match lookup should be used for vBF and non-cache HT. + * + * @param setsum + * Pointer of a set-summary. + * @param key + * Pointer of the key that to be looked up. + * @param max_match_per_key + * User specified maximum number of matches for each key. The function returns + * as soon as this number of matches found for the key. + * @param set_id + * Output set ids for all the matches of the key. User needs to preallocate + * the array that can contain max_match_per_key number of results. + * @return + * The number of matches that found for the key. + * For cache mode HT set-summary, the number should be at most 1. + */ +int +rte_member_lookup_multi(const struct rte_member_setsum *setsum, + const void *key, uint32_t max_match_per_key, + member_set_t *set_id); + +/** + * @warning + * @b EXPERIMENTAL: this API may change without prior notice + * + * Lookup a bulk of keys in set-summary (SS) for multiple matches each key. + * Each key lookup will find all matched entries (multiple match). + * Note that for cache mode HT, each key can have at most one match. So + * multi-match function is mainly used for vBF and non-cache mode HT. + * + * @param setsum + * Pointer of a setsummary. + * @param keys + * Pointer of the keys to be looked up. + * @param num_keys + * The number of keys that will be lookup. + * @param max_match_per_key + * The possible maximum number of matches for each key. + * @param match_count + * Output the number of matches for each key in an array. + * @param set_ids + * Return set ids for all the matches of all keys. Users pass in a + * preallocated 2D array with first dimension as key index and second + * dimension as match index. For example set_ids[bulk_size][max_match_per_key] + * @return + * The number of keys that found one or more matches in the set-summary. + */ +int +rte_member_lookup_multi_bulk(const struct rte_member_setsum *setsum, + const void **keys, uint32_t num_keys, + uint32_t max_match_per_key, + uint32_t *match_count, + member_set_t *set_ids); + +/** + * @warning + * @b EXPERIMENTAL: this API may change without prior notice + * + * Insert key into set-summary (SS). + * + * @param setsum + * Pointer of a set-summary. + * @param key + * Pointer of the key to be added. + * @param set_id + * The set id associated with the key that needs to be added. Different mode + * supports different set_id ranges. 0 cannot be used as set_id since + * RTE_MEMBER_NO_MATCH by default is set as 0. + * For HT mode, the set_id has range as [1, 0x7FFF], MSB is reserved. + * For vBF mode the set id is limited by the num_set parameter when create + * the set-summary. + * @return + * HT (cache mode) and vBF should never fail unless the set_id is not in the + * valid range. In such case -EINVAL is returned. + * For HT (non-cache mode) it could fail with -ENOSPC error code when table is + * full. + * For success it returns different values for different modes to provide + * extra information for users. + * Return 0 for HT (cache mode) if the add does not cause + * eviction, return 1 otherwise. Return 0 for non-cache mode if success, + * -ENOSPC for full, and 1 if cuckoo eviction happens. + * Always returns 0 for vBF mode. + */ +int +rte_member_add(const struct rte_member_setsum *setsum, const void *key, + member_set_t set_id); + +/** + * @warning + * @b EXPERIMENTAL: this API may change without prior notice + * + * De-allocate memory used by set-summary. + * + * @param setsum + * Pointer to the set summary. + */ +void +rte_member_free(struct rte_member_setsum *setsum); + +/** + * @warning + * @b EXPERIMENTAL: this API may change without prior notice + * + * Reset the set-summary tables. E.g. reset bits to be 0 in BF, + * reset set_id in each entry to be RTE_MEMBER_NO_MATCH in HT based SS. + * + * @param setsum + * Pointer to the set-summary. + */ +void +rte_member_reset(const struct rte_member_setsum *setsum); + +/** + * @warning + * @b EXPERIMENTAL: this API may change without prior notice + * + * Delete items from the set-summary. Note that vBF does not support deletion + * in current implementation. For vBF, error code of -EINVAL will be returned. + * + * @param setsum + * Pointer to the set-summary. + * @param key + * Pointer of the key to be deleted. + * @param set_id + * For HT mode, we need both key and its corresponding set_id to + * properly delete the key. Without set_id, we may delete other keys with the + * same signature. + * @return + * If no entry found to delete, an error code of -ENOENT could be returned. + */ +int +rte_member_delete(const struct rte_member_setsum *setsum, const void *key, + member_set_t set_id); + +#ifdef __cplusplus +} +#endif + +#endif /* _RTE_MEMBER_H_ */ |