/* Copyright (c) 2014 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. */ /** @cond DOCUMENTATION_IS_IN_BIHASH_DOC_H */ /* * Note: to instantiate the template multiple times in a single file, * #undef __included_bihash_template_h__... */ #ifndef __included_bihash_template_h__ #define __included_bihash_template_h__ #include <vppinfra/heap.h> #include <vppinfra/format.h> #include <vppinfra/pool.h> #include <vppinfra/cache.h> #ifndef BIHASH_TYPE #error BIHASH_TYPE not defined #endif #define _bv(a,b) a##b #define __bv(a,b) _bv(a,b) #define BV(a) __bv(a,BIHASH_TYPE) #define _bvt(a,b) a##b##_t #define __bvt(a,b) _bvt(a,b) #define BVT(a) __bvt(a,BIHASH_TYPE) typedef struct BV (clib_bihash_value) { union { BVT (clib_bihash_kv) kvp[BIHASH_KVP_PER_PAGE]; struct BV (clib_bihash_value) * next_free; }; } BVT (clib_bihash_value); #define BIHASH_BUCKET_OFFSET_BITS 36 typedef struct { union { struct { u64 offset:BIHASH_BUCKET_OFFSET_BITS; u64 lock:1; u64 linear_search:1; u64 log2_pages:8; i64 refcnt:16; }; u64 as_u64; }; } BVT (clib_bihash_bucket); STATIC_ASSERT_SIZEOF (BVT (clib_bihash_bucket), sizeof (u64)); typedef struct { BVT (clib_bihash_value) * values; BVT (clib_bihash_bucket) * buckets; volatile u32 *alloc_lock; BVT (clib_bihash_value) ** working_copies; int *working_copy_lengths; BVT (clib_bihash_bucket) saved_bucket; u32 nbuckets; u32 log2_nbuckets; u8 *name; u64 cache_hits; u64 cache_misses; BVT (clib_bihash_value) ** freelists; /* * Backing store allocation. Since bihash manages its own * freelists, we simple dole out memory at alloc_arena_next. */ uword alloc_arena; uword alloc_arena_next; uword alloc_arena_size; /** * A custom format function to print the Key and Value of bihash_key instead of default hexdump */ format_function_t *fmt_fn; } BVT (clib_bihash); static inline void BV (clib_bihash_alloc_lock) (BVT (clib_bihash) * h) { while (__atomic_test_and_set (h->alloc_lock, __ATOMIC_ACQUIRE)) ; } static inline void BV (clib_bihash_alloc_unlock) (BVT (clib_bihash) * h) { __atomic_clear (h->alloc_lock, __ATOMIC_RELEASE); } static inline void BV (clib_bihash_lock_bucket) (BVT (clib_bihash_bucket) * b) { BVT (clib_bihash_bucket) unlocked_bucket, locked_bucket; do { locked_bucket.as_u64 = unlocked_bucket.as_u64 = b->as_u64; unlocked_bucket.lock = 0; locked_bucket.lock = 1; } while (__atomic_compare_exchange_n (&b->as_u64, &unlocked_bucket.as_u64, locked_bucket.as_u64, 1 /* weak */ , __ATOMIC_ACQUIRE, __ATOMIC_ACQUIRE) == 0); } static inline void BV (clib_bihash_unlock_bucket) (BVT (clib_bihash_bucket) * b) { CLIB_MEMORY_BARRIER (); b->lock = 0; } static inline void *BV (clib_bihash_get_value) (BVT (clib_bihash) * h, uword offset) { u8 *hp = (u8 *) h->alloc_arena; u8 *vp = hp + offset; return (void *) vp; } static inline int BV (clib_bihash_bucket_is_empty) (BVT (clib_bihash_bucket) * b) { /* Note: applied to locked buckets, test offset */ return b->offset == 0; } static inline uword BV (clib_bihash_get_offset) (BVT (clib_bihash) * h, void *v) { u8 *hp, *vp; hp = (u8 *) h->alloc_arena; vp = (u8 *) v; return vp - hp; } void BV (clib_bihash_init) (BVT (clib_bihash) * h, char *name, u32 nbuckets, uword memory_size); void BV (clib_bihash_set_kvp_format_fn) (BVT (clib_bihash) * h, format_function_t * fmt_fn); void BV (clib_bihash_free) (BVT (clib_bihash) * h); int BV (clib_bihash_add_del) (BVT (clib_bihash) * h, BVT (clib_bihash_kv) * add_v, int is_add); int BV (clib_bihash_search) (BVT (clib_bihash) * h, BVT (clib_bihash_kv) * search_v, BVT (clib_bihash_kv) * return_v); void BV (clib_bihash_foreach_key_value_pair) (BVT (clib_bihash) * h, void *callback, void *arg); format_function_t BV (format_bihash); format_function_t BV (format_bihash_kvp); format_function_t BV (format_bihash_lru); static inline int BV (clib_bihash_search_inline_with_hash) (BVT (clib_bihash) * h, u64 hash, BVT (clib_bihash_kv) * key_result) { u32 bucket_index; BVT (clib_bihash_value) * v; BVT (clib_bihash_bucket) * b; int i, limit; bucket_index = hash & (h->nbuckets - 1); b = &h->buckets[bucket_index]; if (PREDICT_FALSE (BV (clib_bihash_bucket_is_empty) (b))) return -1; if (PREDICT_FALSE (b->lock)) { volatile BVT (clib_bihash_bucket) * bv = b; while (bv->lock) ; } hash >>= h->log2_nbuckets; v = BV (clib_bihash_get_value) (h, b->offset); /* If the bucket has unresolvable collisions, use linear search */ limit = BIHASH_KVP_PER_PAGE; v += (b->linear_search == 0) ? hash & ((1 << b->log2_pages) - 1) : 0; if (PREDICT_FALSE (b->linear_search)) limit <<= b->log2_pages; for (i = 0; i < limit; i++) { if (BV (clib_bihash_key_compare) (v->kvp[i].key, key_result->key)) { *key_result = v->kvp[i]; return 0; } } return -1; } static inline int BV (clib_bihash_search_inline) (BVT (clib_bihash) * h, BVT (clib_bihash_kv) * key_result) { u64 hash; hash = BV (clib_bihash_hash) (key_result); return BV (clib_bihash_search_inline_with_hash) (h, hash, key_result); } static inline void BV (clib_bihash_prefetch_bucket) (BVT (clib_bihash) * h, u64 hash) { u32 bucket_index; BVT (clib_bihash_bucket) * b; bucket_index = hash & (h->nbuckets - 1); b = &h->buckets[bucket_index]; CLIB_PREFETCH (b, CLIB_CACHE_LINE_BYTES, READ); } static inline void BV (clib_bihash_prefetch_data) (BVT (clib_bihash) * h, u64 hash) { u32 bucket_index; BVT (clib_bihash_value) * v; BVT (clib_bihash_bucket) * b; bucket_index = hash & (h->nbuckets - 1); b = &h->buckets[bucket_index]; if (PREDICT_FALSE (BV (clib_bihash_bucket_is_empty) (b))) return; hash >>= h->log2_nbuckets; v = BV (clib_bihash_get_value) (h, b->offset); v += (b->linear_search == 0) ? hash & ((1 << b->log2_pages) - 1) : 0; CLIB_PREFETCH (v, CLIB_CACHE_LINE_BYTES, READ); } static inline int BV (clib_bihash_search_inline_2_with_hash) (BVT (clib_bihash) * h, u64 hash, BVT (clib_bihash_kv) * search_key, BVT (clib_bihash_kv) * valuep) { u32 bucket_index; BVT (clib_bihash_value) * v; BVT (clib_bihash_bucket) * b; int i, limit; ASSERT (valuep); bucket_index = hash & (h->nbuckets - 1); b = &h->buckets[bucket_index]; if (PREDICT_FALSE (BV (clib_bihash_bucket_is_empty) (b))) return -1; if (PREDICT_FALSE (b->lock)) { volatile BVT (clib_bihash_bucket) * bv = b; while (bv->lock) ; } hash >>= h->log2_nbuckets; v = BV (clib_bihash_get_value) (h, b->offset); /* If the bucket has unresolvable collisions, use linear search */ limit = BIHASH_KVP_PER_PAGE; v += (b->linear_search == 0) ? hash & ((1 << b->log2_pages) - 1) : 0; if (PREDICT_FALSE (b->linear_search)) limit <<= b->log2_pages; for (i = 0; i < limit; i++) { if (BV (clib_bihash_key_compare) (v->kvp[i].key, search_key->key)) { *valuep = v->kvp[i]; return 0; } } return -1; } static inline int BV (clib_bihash_search_inline_2) (BVT (clib_bihash) * h, BVT (clib_bihash_kv) * search_key, BVT (clib_bihash_kv) * valuep) { u64 hash; hash = BV (clib_bihash_hash) (search_key); return BV (clib_bihash_search_inline_2_with_hash) (h, hash, search_key, valuep); } #endif /* __included_bihash_template_h__ */ /** @endcond */ /* * fd.io coding-style-patch-verification: ON * * Local Variables: * eval: (c-set-style "gnu") * End: */