lib/fib/trie.h

   1 /* SPDX-License-Identifier: BSD-3-Clause
   2  * Copyright(c) 2018 Vladimir Medvedkin <medvedkinv@gmail.com>
   3  * Copyright(c) 2019 Intel Corporation
   4  */
   5
   6 #ifndef _TRIE_H_
   7 #define _TRIE_H_
   8
   9 /**
  10  * @file
  11  * RTE IPv6 Longest Prefix Match (LPM)
  12  */
  13 #include <rte_prefetch.h>
  14 #include <rte_branch_prediction.h>
  15
  16 /* @internal Total number of tbl24 entries. */
  17 #define TRIE_TBL24_NUM_ENT      (1 << 24)
  18 /* Maximum depth value possible for IPv6 LPM. */
  19 #define TRIE_MAX_DEPTH          128
  20 /* @internal Number of entries in a tbl8 group. */
  21 #define TRIE_TBL8_GRP_NUM_ENT   256ULL
  22 /* @internal Total number of tbl8 groups in the tbl8. */
  23 #define TRIE_TBL8_NUM_GROUPS    65536
  24 /* @internal bitmask with valid and valid_group fields set */
  25 #define TRIE_EXT_ENT            1
  26
  27 #define BITMAP_SLAB_BIT_SIZE_LOG2       6
  28 #define BITMAP_SLAB_BIT_SIZE            (1ULL << BITMAP_SLAB_BIT_SIZE_LOG2)
  29 #define BITMAP_SLAB_BITMASK             (BITMAP_SLAB_BIT_SIZE - 1)
  30
  31 struct rte_trie_tbl {
  32         uint32_t        number_tbl8s;   /**< Total number of tbl8s */
  33         uint32_t        rsvd_tbl8s;     /**< Number of reserved tbl8s */
  34         uint32_t        cur_tbl8s;      /**< Current cumber of tbl8s */
  35         uint64_t        def_nh;         /**< Default next hop */
  36         enum rte_fib_trie_nh_sz nh_sz;  /**< Size of nexthop entry */
  37         uint64_t        *tbl8;          /**< tbl8 table. */
  38         uint32_t        *tbl8_pool;     /**< bitmap containing free tbl8 idxes*/
  39         uint32_t        tbl8_pool_pos;
  40         /* tbl24 table. */
  41         __extension__ uint64_t  tbl24[0] __rte_cache_aligned;
  42 };
  43
  44 static inline uint32_t
  45 get_tbl24_idx(const uint8_t *ip)
  46 {
  47         return ip[0] << 16|ip[1] << 8|ip[2];
  48 }
  49
  50 static inline void *
  51 get_tbl24_p(struct rte_trie_tbl *dp, const uint8_t *ip, uint8_t nh_sz)
  52 {
  53         uint32_t tbl24_idx;
  54
  55         tbl24_idx = get_tbl24_idx(ip);
  56         return (void *)&((uint8_t *)dp->tbl24)[tbl24_idx << nh_sz];
  57 }
  58
  59 static inline uint8_t
  60 bits_in_nh(uint8_t nh_sz)
  61 {
  62         return 8 * (1 << nh_sz);
  63 }
  64
  65 static inline uint64_t
  66 get_max_nh(uint8_t nh_sz)
  67 {
  68         return ((1ULL << (bits_in_nh(nh_sz) - 1)) - 1);
  69 }
  70
  71 static inline uint64_t
  72 lookup_msk(uint8_t nh_sz)
  73 {
  74         return ((1ULL << ((1 << (nh_sz + 3)) - 1)) << 1) - 1;
  75 }
  76
  77 static inline uint8_t
  78 get_psd_idx(uint32_t val, uint8_t nh_sz)
  79 {
  80         return val & ((1 << (3 - nh_sz)) - 1);
  81 }
  82
  83 static inline uint32_t
  84 get_tbl_pos(uint32_t val, uint8_t nh_sz)
  85 {
  86         return val >> (3 - nh_sz);
  87 }
  88
  89 static inline uint64_t
  90 get_tbl_val_by_idx(uint64_t *tbl, uint32_t idx, uint8_t nh_sz)
  91 {
  92         return ((tbl[get_tbl_pos(idx, nh_sz)] >> (get_psd_idx(idx, nh_sz) *
  93                 bits_in_nh(nh_sz))) & lookup_msk(nh_sz));
  94 }
  95
  96 static inline void *
  97 get_tbl_p_by_idx(uint64_t *tbl, uint64_t idx, uint8_t nh_sz)
  98 {
  99         return (uint8_t *)tbl + (idx << nh_sz);
 100 }
 101
 102 static inline int
 103 is_entry_extended(uint64_t ent)
 104 {
 105         return (ent & TRIE_EXT_ENT) == TRIE_EXT_ENT;
 106 }
 107
 108 #define LOOKUP_FUNC(suffix, type, nh_sz)                                \
 109 static inline void rte_trie_lookup_bulk_##suffix(void *p,               \
 110         uint8_t ips[][RTE_FIB6_IPV6_ADDR_SIZE],                         \
 111         uint64_t *next_hops, const unsigned int n)                      \
 112 {                                                                       \
 113         struct rte_trie_tbl *dp = (struct rte_trie_tbl *)p;             \
 114         uint64_t tmp;                                                   \
 115         uint32_t i, j;                                                  \
 116                                                                         \
 117         for (i = 0; i < n; i++) {                                       \
 118                 tmp = ((type *)dp->tbl24)[get_tbl24_idx(&ips[i][0])];   \
 119                 j = 3;                                                  \
 120                 while (is_entry_extended(tmp)) {                        \
 121                         tmp = ((type *)dp->tbl8)[ips[i][j++] +          \
 122                                 ((tmp >> 1) * TRIE_TBL8_GRP_NUM_ENT)];  \
 123                 }                                                       \
 124                 next_hops[i] = tmp >> 1;                                \
 125         }                                                               \
 126 }
 127 LOOKUP_FUNC(2b, uint16_t, 1)
 128 LOOKUP_FUNC(4b, uint32_t, 2)
 129 LOOKUP_FUNC(8b, uint64_t, 3)
 130
 131 void *
 132 trie_create(const char *name, int socket_id, struct rte_fib6_conf *conf);
 133
 134 void
 135 trie_free(void *p);
 136
 137 rte_fib6_lookup_fn_t
 138 trie_get_lookup_fn(void *p, enum rte_fib6_lookup_type type);
 139
 140 int
 141 trie_modify(struct rte_fib6 *fib, const uint8_t ip[RTE_FIB6_IPV6_ADDR_SIZE],
 142         uint8_t depth, uint64_t next_hop, int op);
 143
 144 #endif /* _TRIE_H_ */