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Diffstat (limited to 'hicn-plugin/src/hashtb.h')
| -rw-r--r-- | hicn-plugin/src/hashtb.h | 536 |
1 files changed, 0 insertions, 536 deletions
diff --git a/hicn-plugin/src/hashtb.h b/hicn-plugin/src/hashtb.h deleted file mode 100644 index 3965ec65d..000000000 --- a/hicn-plugin/src/hashtb.h +++ /dev/null @@ -1,536 +0,0 @@ -/* - * Copyright (c) 2017-2019 Cisco and/or its affiliates. - * Licensed under the Apache License, Version 2.0 (the "License"); - * you may not use this file except in compliance with the License. - * You may obtain a copy of the License at: - * - * http://www.apache.org/licenses/LICENSE-2.0 - * - * Unless required by applicable law or agreed to in writing, software - * distributed under the License is distributed on an "AS IS" BASIS, - * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. - * See the License for the specific language governing permissions and - * limitations under the License. - */ - -#ifndef __HICN_HASHTB_H__ -#define __HICN_HASHTB_H__ - -#include <stdint.h> -#include <vppinfra/bihash_8_8.h> -#include <vppinfra/bihash_24_8.h> - -#include "params.h" -#include "parser.h" -#include "error.h" - -/** - * @file hashtb.h - * Lookup is finding a hashtable record whose name matches the name being - * looked up. Most of the lookup work is based on the hash value of the two - * names. Note that the intel cache line size is 64 bytes, and some platforms - * load in 2 cache lines together. - * - first step is to match a record at the bucket/slot level (htab has an - * array of htbucket_t/htbc_elmt, where each bucket has 7 slots to hold - * indices for entries.) Matching at this level implies - * - the hashes of the lookup name and the record map to the same bucket - * - the high 32 bits of the hashes (slot bce_hash_msb32s) match. Read - * cost (on the hash table size, i.e. ignoring reading the name being - * looked up): - * - First step normally requires 1 cache line load to pull in the - * 64-byte htbucket_t with the 7 element slot table holding the - * hash_msb32s. - * - In the event (hopefully rare for a hash table with appropriate - * number of buckets) that more than 7 elements hash to the same bucket, - * lookup may well need to look not only at the static htbc_elmt_t but at - * the chain of dynamically allocated htbc_elmt_t's linked to the static - * htbc_elmt_t, where each of these holds slot entries for additional - * elements. - * - Before reaching that point, it is initially required to read in the - * hash table record fields (ht_bucket_buf, htnode buf, etc) holding - * pointers to the arrays, but these cache lines are common to all - * lookups so will likely already be in the cache. - * - second step is to match at the record level (htnode/htkb level) once a - * slot-level match happens. Matching at this level implies the following - * match - * - the hash values (the full 64 bits vs. bucket+32 msb, above). - * - the name which, on the hash table side, is stored as a list of htkb_t - * (key buffers). - * - * Some hashtables (for which rare false positives are tolerable) store hash - * values but no keys. (In ISM NDN forwarder, this was used for dcm_dpf: data - * cache manager's dataplane filter, where speed was critical and very rare - * false positives would be detected in the full dcm check.) - No key buffers - * are used (or even allocated at hash table creation). - */ - -/* Handy abbreviations for success status, and for boolean values */ -#ifndef TRUE -#define TRUE 1 -#endif - -#ifndef FALSE -#define FALSE 0 -#endif - -#define HICN_HASH_INVALID_IDX ~0 -/* - * for hicn_hashtb_next_node() iterator, this otherwise illegal context value - * indicates first call of iteration. Note: must not be 0, which is a legal - * context value. - */ -#define HICN_HASH_WALK_CTX_INITIAL (~((u64) 0)) - -/* - * Key memory allocation scheme. - * - * The key is the bytestring that a hashtable entry is storing, e.g. a fib - * prefix or packet name. The hash of the name is used not just to pick the - * bucket, but also as a surrogate for the actual key value. - * - * Client calls pass key/name as contiguous memory for lookup/add/delete but - * hashable stores its copy of the key/name as a list of one or more hash_key - * structs. - key memory is managed as a list of keys (cache line - * sized/aligned buffers). - If (keysize < 128) then use key struct's full - * 128 bytes - If not, first key struct is head of a linked list of elements - * where the first bytes are used for the key and the last 4 bytes are the - * index of the next entry (or an end marker). - key memory is generally the - * single largest use of memory in the hash table, especially for PIT, as - * names are bigger than node structs (which is also per name/entry). - * - */ - -/* Compute hash node index from node pointer */ -#define NODE_IDX_FROM_NODE(p, h) (u32) ((p) - ((h)->ht_nodes)) - -#define HICN_HASH_KEY_BYTES 20 - -typedef struct -{ - struct - { - u8 key[HICN_HASH_KEY_BYTES]; - } ks; /* Entire key in one block */ -} hicn_hash_key_t; - -/* - * Ratio of extra key blocks to allocate, in case the embedded ones aren't - * sufficient. This is the fraction of the number of entries allocated. - */ -#define HICN_HASHTB_KEY_RATIO 8 - -/* - * hash node, used to store a hash table entry; indexed by an entry in a - * bucket. the node contains an embedded key; long keys are stored as chains - * of keys. - * - * The memory block for a node includes space for storing outgoing faces for - * interests, additional memory located off the end of the htnode data - * structure. - * - */ - -/* Size this so that we can offer 64B aligned on 64-bits for storing outgoing - * faces information - */ -#define HICN_HASH_NODE_APP_DATA_SIZE 64 - -/* How to align in the right way */ -typedef struct __attribute__ ((packed)) hicn_hash_node_s -{ - /* Bucket id containing the corresponding hash entry. */ - u32 bucket_id; - - /* Hash entry index in the bucket */ - u32 entry_idx; - - /* Total size of the key */ - u16 hn_keysize; - - /* 1 byte of flags for application use */ - u8 hn_flags; - - u8 _hn_reserved1; /* TBD, to align what follows back to - * 32 */ - - hicn_hash_key_t hn_key; /* Key value embedded in the node, may chain - * to more key buffers if necessary */ - - /* 32B + HICN_HASH_NODE_APP_DATA_SIZE */ - /* Followed by app-specific data (fib or pit or cs entry, e.g.) */ - u8 hn_data[HICN_HASH_NODE_APP_DATA_SIZE]; - -} hicn_hash_node_t; - -#define HICN_HASH_NODE_FLAGS_DEFAULT 0x00 -#define HICN_HASH_NODE_CS_FLAGS 0x01 -#define HICN_HASH_NODE_OVERFLOW_BUCKET 0x02 - -/* - * hicn_hash_entry_t Structure holding all or part of a hash value, a node - * index, and other key pieces of info. - * - * - 128 bytes/bucket with 19 bytes/entry gives 6 entries, or 5 entries plus - * next bucket ptr if overflow Changes in this structure will affect - * hicn_hash_bucket_t - */ -typedef struct __attribute__ ((packed)) hicn_hash_entry_s -{ - - /* MSB of the hash value */ - u64 he_msb64; - - /* Index of node block */ - u32 he_node; - - /* - * Lock to prevent hash_node deletion while there are still interest - * or data referring to it - */ - u32 locks; - - /* Index of dpo (4B) */ - index_t dpo_ctx_id; - - /* A few flags, including 'this points to a chain of buckets' */ - u8 he_flags; - - /* - * Index of the virtual function table corresponding to the dpo_ctx - * strategy - */ - u8 vft_id; - -} hicn_hash_entry_t; // size 22B - -STATIC_ASSERT (sizeof (index_t) <= 4, "sizeof index_t is greater than 4B"); - -#define HICN_HASH_ENTRY_FLAGS_DEFAULT 0x00 - -/* If entry is PIT this flag is 0 */ -#define HICN_HASH_ENTRY_FLAG_CS_ENTRY 0x01 - -/* - * This entry heads a chain of overflow buckets (we expect to see this only - * in the last entry in a bucket.) In this case, the index is to an overflow - * bucket rather than to a single node block. - */ -#define HICN_HASH_ENTRY_FLAG_OVERFLOW 0x04 - -/* This entry has been marked for deletion */ -#define HICN_HASH_ENTRY_FLAG_DELETED 0x08 - -/* Use fast he_timeout units for expiration, slow if not */ -#define HICN_HASH_ENTRY_FLAG_FAST_TIMEOUT 0x10 - -/* - * hash bucket: Contains an array of entries. Cache line sized/aligned, so no - * room for extra fields unless bucket size is increased to 2 cache lines or - * the entry struct shrinks. - */ - -/* - * Overflow bucket ratio as a fraction of the fixed/configured count; a pool - * of hash buckets used if a row in the fixed table overflows. - */ -#define HICN_HASHTB_BUCKET_ENTRIES 5 - -typedef struct __attribute__ ((packed)) -{ - hicn_hash_entry_t hb_entries[HICN_HASHTB_BUCKET_ENTRIES]; - u64 align1; - u64 align2; - u16 align3; -} hicn_hash_bucket_t; - -/* Overall target fill-factor for the hashtable */ -#define HICN_HASHTB_FILL_FACTOR 4 - -#define HICN_HASHTB_MIN_ENTRIES (1 << 4) // includes dummy node 0 entry -#define HICN_HASHTB_MAX_ENTRIES (1 << 24) - -#define HICN_HASHTB_MIN_BUCKETS (1 << 10) - -/* - * htab_t - * - * Hash table main structure. - * - * Contains - pointers to dynamically allocated arrays of cache-line - * sized/aligned structures (buckets, nodes, keys). Put frequently accessed - * fields in the first cache line. - */ -typedef struct hicn_hashtb_s -{ - - /* 8B - main array of hash buckets */ - hicn_hash_bucket_t *ht_buckets; - - /* 8B - just-in-case block of overflow buckets */ - hicn_hash_bucket_t *ht_overflow_buckets; - - /* 8B - block of nodes associated with entries in buckets */ - hicn_hash_node_t *ht_nodes; - - /* Flags */ - u32 ht_flags; - - /* Count of buckets allocated in the main array */ - u32 ht_bucket_count; - - /* Count of overflow buckets allocated */ - u32 ht_overflow_bucket_count; - u32 ht_overflow_buckets_used; - - /* Count of nodes allocated */ - u32 ht_node_count; - u32 ht_nodes_used; - - /* Count of overflow key structs allocated */ - u32 ht_key_count; - u32 ht_keys_used; - -} hicn_hashtb_t, *hicn_hashtb_h; - -/* - * Offset to aligned start of additional data (PIT/CS, FIB) embedded in each - * node. - */ -extern u32 ht_node_data_offset_aligned; - -/* Flags for hashtable */ - -#define HICN_HASHTB_FLAGS_DEFAULT 0x00 - -/* - * Don't use the last entry in each bucket - only use it for overflow. We use - * this for the FIB, currently, so that we can support in-place FIB changes - * that would be difficult if there were hash entry copies as part of - * overflow handling. - */ -#define HICN_HASHTB_FLAG_USE_SEVEN 0x04 -#define HICN_HASHTB_FLAG_KEY_FMT_PFX 0x08 -#define HICN_HASHTB_FLAG_KEY_FMT_NAME 0x10 - -/* - * Max prefix name components we'll support in our incremental hashing; - * currently used only for LPM in the FIB. - */ -#define HICN_HASHTB_MAX_NAME_COMPS HICN_PARAM_FIB_ENTRY_PFX_COMPS_MAX - -/* - * APIs and inlines - */ - -/* Compute hash node index from node pointer */ -static inline u32 -hicn_hashtb_node_idx_from_node (hicn_hashtb_h h, hicn_hash_node_t *p) -{ - return (p - h->ht_nodes); -} - -/* Retrieve a hashtable node by node index */ -static inline hicn_hash_node_t * -hicn_hashtb_node_from_idx (hicn_hashtb_h h, u32 idx) -{ - return (pool_elt_at_index (h->ht_nodes, idx)); -} - -/* Allocate a brand-new hashtable */ -int hicn_hashtb_alloc (hicn_hashtb_h *ph, u32 max_elems, size_t app_data_size); - -/* Free a hashtable, including its embedded arrays */ -int hicn_hashtb_free (hicn_hashtb_h *ph); - -/* Hash a bytestring, currently using bihash */ -u64 hicn_hashtb_hash_bytestring (const u8 *key, u32 keylen); - -always_inline hicn_hash_entry_t * -hicn_hashtb_get_entry (hicn_hashtb_h h, u32 entry_idx, u32 bucket_id, - u8 bucket_overflow) -{ - hicn_hash_bucket_t *bucket; - if (bucket_overflow) - bucket = pool_elt_at_index (h->ht_overflow_buckets, bucket_id); - else - bucket = (hicn_hash_bucket_t *) (h->ht_buckets + bucket_id); - - return &(bucket->hb_entries[entry_idx]); -} - -/* Hash a name, currently using bihash */ -always_inline u64 -hicn_hashtb_hash_name (const u8 *key, u16 keylen) -{ - if (key != NULL && keylen == HICN_V4_NAME_LEN) - { - clib_bihash_kv_8_8_t kv; - kv.key = ((u64 *) key)[0]; - return clib_bihash_hash_8_8 (&kv); - } - else if (key != NULL && keylen == HICN_V6_NAME_LEN) - { - clib_bihash_kv_24_8_t kv; - kv.key[0] = ((u64 *) key)[0]; - kv.key[1] = ((u64 *) key)[1]; - kv.key[2] = ((u32 *) key)[4]; - return clib_bihash_hash_24_8 (&kv); - } - else - { - return (-1LL); - } -} - -/* - * Prepare a hashtable node for insertion, supplying the key and computed - * hash info. This sets up the node->key relationship, possibly allocating - * overflow key buffers. - */ -void hicn_hashtb_init_node (hicn_hashtb_h h, hicn_hash_node_t *node, - const u8 *key, u32 keylen); - -/* - * Insert a node into the hashtable. We expect the caller has used the init - * api to set the node key and hash info, and populated the extra data area - * (if any) - or done the equivalent work itself. - */ -int hicn_hashtb_insert (hicn_hashtb_h h, hicn_hash_node_t *node, - hicn_hash_entry_t **hash_entry, u64 hash, u32 *node_id, - index_t *dpo_ctx_id, u8 *vft_id, u8 *is_cs, - u8 *hash_entry_id, u32 *bucket_id, - u8 *bucket_is_overflow); - -/* - * Basic api to lookup a specific hash+key tuple. This does the entire lookup - * operation, retrieving node structs and comparing keys, so it's not - * optimized for prefetching or high performance. - * - * Returns zero and mails back a node on success, errno otherwise. - */ -int hicn_hashtb_lookup_node (hicn_hashtb_h h, const u8 *key, u32 keylen, - u64 hashval, u8 is_data, u32 *node_id, - index_t *dpo_ctx_id, u8 *vft_id, u8 *is_cs, - u8 *hash_entry_id, u32 *bucket_id, - u8 *bucket_is_overflow); - -/* - * Extended api to lookup a specific hash+key tuple. The implementation - * allows the caller to locate nodes that are marked for deletion; this is - * part of some hashtable applications, such as the FIB. - * - * This does the entire lookup operation, retrieving node structs and comparing - * keys, so it's not optimized for prefetching or high performance. - * - * Returns zero and mails back a node on success, errno otherwise. - */ -int hicn_hashtb_lookup_node_ex (hicn_hashtb_h h, const u8 *key, u32 keylen, - u64 hashval, u8 is_data, int include_deleted_p, - u32 *node_id, index_t *dpo_ctx_id, u8 *vft_id, - u8 *is_cs, u8 *hash_entry_id, u32 *bucket_id, - u8 *bucket_is_overflow); - -/** - * @brief Compares the key in the node with the given key - * - * This function allows to split the hash verification from the comparison of - * the entire key. Useful to exploit prefertching. - * @result 1 if equals, 0 otherwise - */ -int hicn_node_compare (const u8 *key, u32 keylen, hicn_hash_node_t *node); - -/* - * Remove a node from a hashtable using the node itself. The internal data - * structs are cleaned up, but the node struct itself is not: the caller must - * free the node itself. - */ -void hicn_hashtb_remove_node (hicn_hashtb_h h, hicn_hash_node_t *node, - u64 hashval); - -/* - * Delete a node from a hashtable using the node itself, and delete/free the - * node. Caller's pointer is cleared on success. - */ -void hicn_hashtb_delete (hicn_hashtb_h h, hicn_hash_node_t **pnode, - u64 hashval); - -/* - * Utility to init a new entry in a hashtable bucket/row. We use this to add - * new a node+hash, and to clear out an entry during removal. - */ -void hicn_hashtb_init_entry (hicn_hash_entry_t *entry, u32 nodeidx, - u64 hashval, u32 locks); - -/* - * Return data area embedded in a hash node struct. We maintain an 'offset' - * value in case the common node body struct doesn't leave the data area - * aligned properly. - */ -static inline void * -hicn_hashtb_node_data (hicn_hash_node_t *node) -{ - return ((u8 *) (node) + ht_node_data_offset_aligned); -} - -/* - * Use some bits of the low half of the hash to locate a row/bucket in the - * table - */ -static inline u32 -hicn_hashtb_bucket_idx (hicn_hashtb_h h, u64 hashval) -{ - return ((u32) (hashval & (h->ht_bucket_count - 1))); -} - -/* - * Return a hash node struct from the free list, or NULL. Note that the - * returned struct is _not_ cleared/zeroed - init is up to the caller. - */ -static inline hicn_hash_node_t * -hicn_hashtb_alloc_node (hicn_hashtb_h h) -{ - hicn_hash_node_t *p = NULL; - - if (h->ht_nodes_used < h->ht_node_count) - { - pool_get_aligned (h->ht_nodes, p, 8); - h->ht_nodes_used++; - } - return (p); -} - -/* - * Release a hashtable node back to the free list when an entry is cleared - */ -void hicn_hashtb_free_node (hicn_hashtb_h h, hicn_hash_node_t *node); - -/* - * Walk a hashtable, iterating through the nodes, keeping context in 'ctx' - * between calls. - * - * Set the context value to HICN_HASH_WALK_CTX_INITIAL to start an iteration. - */ -int hicn_hashtb_next_node (hicn_hashtb_h h, hicn_hash_node_t **pnode, - u64 *ctx); - -int hicn_hashtb_key_to_str (hicn_hashtb_h h, const hicn_hash_node_t *node, - char *buf, int bufsize, int must_fit); - -/* - * single hash full name can pass offset for two hashes calculation in case - * we use CS and PIT in a two steps hashes (prefix + seqno) - */ -always_inline int -hicn_hashtb_fullhash (const u8 *name, u16 namelen, u64 *name_hash) -{ - *name_hash = hicn_hashtb_hash_name (name, namelen); - return (*name_hash != (-1LL) ? HICN_ERROR_NONE : HICN_ERROR_HASHTB_INVAL); -} - -#endif /* // __HICN_HASHTB_H__ */ - -/* - * fd.io coding-style-patch-verification: ON - * - * Local Variables: eval: (c-set-style "gnu") End: - */ |