xref: /dpdk/lib/fib/trie.h (revision 9ad3a41ab2a10db0059e1decdbf3ec038f348e08)
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 
14 /* @internal Total number of tbl24 entries. */
15 #define TRIE_TBL24_NUM_ENT	(1 << 24)
16 /* Maximum depth value possible for IPv6 LPM. */
17 #define TRIE_MAX_DEPTH		128
18 /* @internal Number of entries in a tbl8 group. */
19 #define TRIE_TBL8_GRP_NUM_ENT	256ULL
20 /* @internal Total number of tbl8 groups in the tbl8. */
21 #define TRIE_TBL8_NUM_GROUPS	65536
22 /* @internal bitmask with valid and valid_group fields set */
23 #define TRIE_EXT_ENT		1
24 
25 #define BITMAP_SLAB_BIT_SIZE_LOG2	6
26 #define BITMAP_SLAB_BIT_SIZE		(1ULL << BITMAP_SLAB_BIT_SIZE_LOG2)
27 #define BITMAP_SLAB_BITMASK		(BITMAP_SLAB_BIT_SIZE - 1)
28 
29 struct rte_trie_tbl {
30 	uint32_t	number_tbl8s;	/**< Total number of tbl8s */
31 	uint32_t	rsvd_tbl8s;	/**< Number of reserved tbl8s */
32 	uint32_t	cur_tbl8s;	/**< Current cumber of tbl8s */
33 	uint64_t	def_nh;		/**< Default next hop */
34 	enum rte_fib_trie_nh_sz	nh_sz;	/**< Size of nexthop entry */
35 	uint64_t	*tbl8;		/**< tbl8 table. */
36 	uint32_t	*tbl8_pool;	/**< bitmap containing free tbl8 idxes*/
37 	uint32_t	tbl8_pool_pos;
38 	/* tbl24 table. */
39 	__extension__ uint64_t	tbl24[0] __rte_cache_aligned;
40 };
41 
42 static inline uint32_t
43 get_tbl24_idx(const uint8_t *ip)
44 {
45 	return ip[0] << 16|ip[1] << 8|ip[2];
46 }
47 
48 static inline void *
49 get_tbl24_p(struct rte_trie_tbl *dp, const uint8_t *ip, uint8_t nh_sz)
50 {
51 	uint32_t tbl24_idx;
52 
53 	tbl24_idx = get_tbl24_idx(ip);
54 	return (void *)&((uint8_t *)dp->tbl24)[tbl24_idx << nh_sz];
55 }
56 
57 static inline uint8_t
58 bits_in_nh(uint8_t nh_sz)
59 {
60 	return 8 * (1 << nh_sz);
61 }
62 
63 static inline uint64_t
64 get_max_nh(uint8_t nh_sz)
65 {
66 	return ((1ULL << (bits_in_nh(nh_sz) - 1)) - 1);
67 }
68 
69 static inline uint64_t
70 lookup_msk(uint8_t nh_sz)
71 {
72 	return ((1ULL << ((1 << (nh_sz + 3)) - 1)) << 1) - 1;
73 }
74 
75 static inline uint8_t
76 get_psd_idx(uint32_t val, uint8_t nh_sz)
77 {
78 	return val & ((1 << (3 - nh_sz)) - 1);
79 }
80 
81 static inline uint32_t
82 get_tbl_pos(uint32_t val, uint8_t nh_sz)
83 {
84 	return val >> (3 - nh_sz);
85 }
86 
87 static inline uint64_t
88 get_tbl_val_by_idx(uint64_t *tbl, uint32_t idx, uint8_t nh_sz)
89 {
90 	return ((tbl[get_tbl_pos(idx, nh_sz)] >> (get_psd_idx(idx, nh_sz) *
91 		bits_in_nh(nh_sz))) & lookup_msk(nh_sz));
92 }
93 
94 static inline void *
95 get_tbl_p_by_idx(uint64_t *tbl, uint64_t idx, uint8_t nh_sz)
96 {
97 	return (uint8_t *)tbl + (idx << nh_sz);
98 }
99 
100 static inline int
101 is_entry_extended(uint64_t ent)
102 {
103 	return (ent & TRIE_EXT_ENT) == TRIE_EXT_ENT;
104 }
105 
106 #define LOOKUP_FUNC(suffix, type, nh_sz)				\
107 static inline void rte_trie_lookup_bulk_##suffix(void *p,		\
108 	uint8_t ips[][RTE_FIB6_IPV6_ADDR_SIZE],				\
109 	uint64_t *next_hops, const unsigned int n)			\
110 {									\
111 	struct rte_trie_tbl *dp = (struct rte_trie_tbl *)p;		\
112 	uint64_t tmp;							\
113 	uint32_t i, j;							\
114 									\
115 	for (i = 0; i < n; i++) {					\
116 		tmp = ((type *)dp->tbl24)[get_tbl24_idx(&ips[i][0])];	\
117 		j = 3;							\
118 		while (is_entry_extended(tmp)) {			\
119 			tmp = ((type *)dp->tbl8)[ips[i][j++] +		\
120 				((tmp >> 1) * TRIE_TBL8_GRP_NUM_ENT)];	\
121 		}							\
122 		next_hops[i] = tmp >> 1;				\
123 	}								\
124 }
125 LOOKUP_FUNC(2b, uint16_t, 1)
126 LOOKUP_FUNC(4b, uint32_t, 2)
127 LOOKUP_FUNC(8b, uint64_t, 3)
128 
129 void *
130 trie_create(const char *name, int socket_id, struct rte_fib6_conf *conf);
131 
132 void
133 trie_free(void *p);
134 
135 rte_fib6_lookup_fn_t
136 trie_get_lookup_fn(void *p, enum rte_fib6_lookup_type type);
137 
138 int
139 trie_modify(struct rte_fib6 *fib, const uint8_t ip[RTE_FIB6_IPV6_ADDR_SIZE],
140 	uint8_t depth, uint64_t next_hop, int op);
141 
142 #endif /* _TRIE_H_ */
143