xref: /dpdk/lib/fib/dir24_8.h (revision daa02b5cddbb8e11b31d41e2bf7bb1ae64dcae2f)
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 _DIR24_8_H_
7 #define _DIR24_8_H_
8 
9 #include <rte_prefetch.h>
10 #include <rte_branch_prediction.h>
11 
12 /**
13  * @file
14  * DIR24_8 algorithm
15  */
16 
17 #define DIR24_8_TBL24_NUM_ENT		(1 << 24)
18 #define DIR24_8_TBL8_GRP_NUM_ENT	256U
19 #define DIR24_8_EXT_ENT			1
20 #define DIR24_8_TBL24_MASK		0xffffff00
21 
22 #define BITMAP_SLAB_BIT_SIZE_LOG2	6
23 #define BITMAP_SLAB_BIT_SIZE		(1 << BITMAP_SLAB_BIT_SIZE_LOG2)
24 #define BITMAP_SLAB_BITMASK		(BITMAP_SLAB_BIT_SIZE - 1)
25 
26 struct dir24_8_tbl {
27 	uint32_t	number_tbl8s;	/**< Total number of tbl8s */
28 	uint32_t	rsvd_tbl8s;	/**< Number of reserved tbl8s */
29 	uint32_t	cur_tbl8s;	/**< Current number of tbl8s */
30 	enum rte_fib_dir24_8_nh_sz	nh_sz;	/**< Size of nexthop entry */
31 	uint64_t	def_nh;		/**< Default next hop */
32 	uint64_t	*tbl8;		/**< tbl8 table. */
33 	uint64_t	*tbl8_idxes;	/**< bitmap containing free tbl8 idxes*/
34 	/* tbl24 table. */
35 	__extension__ uint64_t	tbl24[0] __rte_cache_aligned;
36 };
37 
38 static inline void *
39 get_tbl24_p(struct dir24_8_tbl *dp, uint32_t ip, uint8_t nh_sz)
40 {
41 	return (void *)&((uint8_t *)dp->tbl24)[(ip &
42 		DIR24_8_TBL24_MASK) >> (8 - nh_sz)];
43 }
44 
45 static inline  uint8_t
46 bits_in_nh(uint8_t nh_sz)
47 {
48 	return 8 * (1 << nh_sz);
49 }
50 
51 static inline uint64_t
52 get_max_nh(uint8_t nh_sz)
53 {
54 	return ((1ULL << (bits_in_nh(nh_sz) - 1)) - 1);
55 }
56 
57 static  inline uint32_t
58 get_tbl24_idx(uint32_t ip)
59 {
60 	return ip >> 8;
61 }
62 
63 static  inline uint32_t
64 get_tbl8_idx(uint32_t res, uint32_t ip)
65 {
66 	return (res >> 1) * DIR24_8_TBL8_GRP_NUM_ENT + (uint8_t)ip;
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_idx(uint32_t val, uint8_t nh_sz)
83 {
84 	return val >> (3 - nh_sz);
85 }
86 
87 static inline uint64_t
88 get_tbl24(struct dir24_8_tbl *dp, uint32_t ip, uint8_t nh_sz)
89 {
90 	return ((dp->tbl24[get_tbl_idx(get_tbl24_idx(ip), nh_sz)] >>
91 		(get_psd_idx(get_tbl24_idx(ip), nh_sz) *
92 		bits_in_nh(nh_sz))) & lookup_msk(nh_sz));
93 }
94 
95 static inline uint64_t
96 get_tbl8(struct dir24_8_tbl *dp, uint32_t res, uint32_t ip, uint8_t nh_sz)
97 {
98 	return ((dp->tbl8[get_tbl_idx(get_tbl8_idx(res, ip), nh_sz)] >>
99 		(get_psd_idx(get_tbl8_idx(res, ip), nh_sz) *
100 		bits_in_nh(nh_sz))) & lookup_msk(nh_sz));
101 }
102 
103 static inline int
104 is_entry_extended(uint64_t ent)
105 {
106 	return (ent & DIR24_8_EXT_ENT) == DIR24_8_EXT_ENT;
107 }
108 
109 #define LOOKUP_FUNC(suffix, type, bulk_prefetch, nh_sz)			\
110 static inline void dir24_8_lookup_bulk_##suffix(void *p, const uint32_t *ips, \
111 	uint64_t *next_hops, const unsigned int n)			\
112 {									\
113 	struct dir24_8_tbl *dp = (struct dir24_8_tbl *)p;		\
114 	uint64_t tmp;							\
115 	uint32_t i;							\
116 	uint32_t prefetch_offset =					\
117 		RTE_MIN((unsigned int)bulk_prefetch, n);		\
118 									\
119 	for (i = 0; i < prefetch_offset; i++)				\
120 		rte_prefetch0(get_tbl24_p(dp, ips[i], nh_sz));		\
121 	for (i = 0; i < (n - prefetch_offset); i++) {			\
122 		rte_prefetch0(get_tbl24_p(dp,				\
123 			ips[i + prefetch_offset], nh_sz));		\
124 		tmp = ((type *)dp->tbl24)[ips[i] >> 8];			\
125 		if (unlikely(is_entry_extended(tmp)))			\
126 			tmp = ((type *)dp->tbl8)[(uint8_t)ips[i] +	\
127 				((tmp >> 1) * DIR24_8_TBL8_GRP_NUM_ENT)]; \
128 		next_hops[i] = tmp >> 1;				\
129 	}								\
130 	for (; i < n; i++) {						\
131 		tmp = ((type *)dp->tbl24)[ips[i] >> 8];			\
132 		if (unlikely(is_entry_extended(tmp)))			\
133 			tmp = ((type *)dp->tbl8)[(uint8_t)ips[i] +	\
134 				((tmp >> 1) * DIR24_8_TBL8_GRP_NUM_ENT)]; \
135 		next_hops[i] = tmp >> 1;				\
136 	}								\
137 }									\
138 
139 LOOKUP_FUNC(1b, uint8_t, 5, 0)
140 LOOKUP_FUNC(2b, uint16_t, 6, 1)
141 LOOKUP_FUNC(4b, uint32_t, 15, 2)
142 LOOKUP_FUNC(8b, uint64_t, 12, 3)
143 
144 static inline void
145 dir24_8_lookup_bulk(struct dir24_8_tbl *dp, const uint32_t *ips,
146 	uint64_t *next_hops, const unsigned int n, uint8_t nh_sz)
147 {
148 	uint64_t tmp;
149 	uint32_t i;
150 	uint32_t prefetch_offset = RTE_MIN(15U, n);
151 
152 	for (i = 0; i < prefetch_offset; i++)
153 		rte_prefetch0(get_tbl24_p(dp, ips[i], nh_sz));
154 	for (i = 0; i < (n - prefetch_offset); i++) {
155 		rte_prefetch0(get_tbl24_p(dp, ips[i + prefetch_offset],
156 			nh_sz));
157 		tmp = get_tbl24(dp, ips[i], nh_sz);
158 		if (unlikely(is_entry_extended(tmp)))
159 			tmp = get_tbl8(dp, tmp, ips[i], nh_sz);
160 
161 		next_hops[i] = tmp >> 1;
162 	}
163 	for (; i < n; i++) {
164 		tmp = get_tbl24(dp, ips[i], nh_sz);
165 		if (unlikely(is_entry_extended(tmp)))
166 			tmp = get_tbl8(dp, tmp, ips[i], nh_sz);
167 
168 		next_hops[i] = tmp >> 1;
169 	}
170 }
171 
172 static inline void
173 dir24_8_lookup_bulk_0(void *p, const uint32_t *ips,
174 	uint64_t *next_hops, const unsigned int n)
175 {
176 	struct dir24_8_tbl *dp = (struct dir24_8_tbl *)p;
177 
178 	dir24_8_lookup_bulk(dp, ips, next_hops, n, 0);
179 }
180 
181 static inline void
182 dir24_8_lookup_bulk_1(void *p, const uint32_t *ips,
183 	uint64_t *next_hops, const unsigned int n)
184 {
185 	struct dir24_8_tbl *dp = (struct dir24_8_tbl *)p;
186 
187 	dir24_8_lookup_bulk(dp, ips, next_hops, n, 1);
188 }
189 
190 static inline void
191 dir24_8_lookup_bulk_2(void *p, const uint32_t *ips,
192 	uint64_t *next_hops, const unsigned int n)
193 {
194 	struct dir24_8_tbl *dp = (struct dir24_8_tbl *)p;
195 
196 	dir24_8_lookup_bulk(dp, ips, next_hops, n, 2);
197 }
198 
199 static inline void
200 dir24_8_lookup_bulk_3(void *p, const uint32_t *ips,
201 	uint64_t *next_hops, const unsigned int n)
202 {
203 	struct dir24_8_tbl *dp = (struct dir24_8_tbl *)p;
204 
205 	dir24_8_lookup_bulk(dp, ips, next_hops, n, 3);
206 }
207 
208 static inline void
209 dir24_8_lookup_bulk_uni(void *p, const uint32_t *ips,
210 	uint64_t *next_hops, const unsigned int n)
211 {
212 	struct dir24_8_tbl *dp = (struct dir24_8_tbl *)p;
213 	uint64_t tmp;
214 	uint32_t i;
215 	uint32_t prefetch_offset = RTE_MIN(15U, n);
216 	uint8_t nh_sz = dp->nh_sz;
217 
218 	for (i = 0; i < prefetch_offset; i++)
219 		rte_prefetch0(get_tbl24_p(dp, ips[i], nh_sz));
220 	for (i = 0; i < (n - prefetch_offset); i++) {
221 		rte_prefetch0(get_tbl24_p(dp, ips[i + prefetch_offset],
222 			nh_sz));
223 		tmp = get_tbl24(dp, ips[i], nh_sz);
224 		if (unlikely(is_entry_extended(tmp)))
225 			tmp = get_tbl8(dp, tmp, ips[i], nh_sz);
226 
227 		next_hops[i] = tmp >> 1;
228 	}
229 	for (; i < n; i++) {
230 		tmp = get_tbl24(dp, ips[i], nh_sz);
231 		if (unlikely(is_entry_extended(tmp)))
232 			tmp = get_tbl8(dp, tmp, ips[i], nh_sz);
233 
234 		next_hops[i] = tmp >> 1;
235 	}
236 }
237 
238 void *
239 dir24_8_create(const char *name, int socket_id, struct rte_fib_conf *conf);
240 
241 void
242 dir24_8_free(void *p);
243 
244 rte_fib_lookup_fn_t
245 dir24_8_get_lookup_fn(void *p, enum rte_fib_lookup_type type);
246 
247 int
248 dir24_8_modify(struct rte_fib *fib, uint32_t ip, uint8_t depth,
249 	uint64_t next_hop, int op);
250 
251 #endif /* _DIR24_8_H_ */
252