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Vector Packet Processing
load_balance.h
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1 /*
2  * Copyright (c) 2016 Cisco and/or its affiliates.
3  * Licensed under the Apache License, Version 2.0 (the "License");
4  * you may not use this file except in compliance with the License.
5  * You may obtain a copy of the License at:
6  *
7  * http://www.apache.org/licenses/LICENSE-2.0
8  *
9  * Unless required by applicable law or agreed to in writing, software
10  * distributed under the License is distributed on an "AS IS" BASIS,
11  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12  * See the License for the specific language governing permissions and
13  * limitations under the License.
14  */
15 /**
16  * \brief
17  * The load-balance object represents an ECMP choice. The buckets of a load
18  * balance object point to the sub-graph after the choice is made.
19  * THe load-balance object is also object type returned from a FIB table lookup.
20  * As such it needs to represent the case where there is only one coice. It may
21  * seem like overkill to use a load-balance object in this case, but the reason
22  * is for performance. If the load-balance object were not the result of the FIB
23  * lookup, then some other object would be. The case where there was ECMP
24  * this other object would need a load-balance as a parent and hence just add
25  * an unnecessary indirection.
26  *
27  * It is also the object in the DP that represents a via-fib-entry in a recursive
28  * route.
29  *
30  */
31 
32 #ifndef __LOAD_BALANCE_H__
33 #define __LOAD_BALANCE_H__
34 
35 #include <vlib/vlib.h>
36 #include <vnet/ip/lookup.h>
37 #include <vnet/dpo/dpo.h>
38 #include <vnet/fib/fib_types.h>
39 #include <vnet/fib/fib_entry.h>
40 
41 /**
42  * Load-balance main
43  */
44 typedef struct load_balance_main_t_
45 {
49 
51 
52 /**
53  * The number of buckets that a load-balance object can have and still
54  * fit in one cache-line
55  */
56 #define LB_NUM_INLINE_BUCKETS 4
57 
58 /**
59  * @brief One path from an [EU]CMP set that the client wants to add to a
60  * load-balance object
61  */
62 typedef struct load_balance_path_t_ {
63  /**
64  * ID of the Data-path object.
65  */
67 
68  /**
69  * The index of the FIB path
70  */
72 
73  /**
74  * weight for the path.
75  */
78 
79 /**
80  * Flags controlling load-balance creation and modification
81  */
82 typedef enum load_balance_attr_t_ {
86 
87 #define LOAD_BALANCE_ATTR_NAMES { \
88  [LOAD_BALANCE_ATTR_USES_MAP] = "uses-map", \
89  [LOAD_BALANCE_ATTR_STICKY] = "sticky", \
90 }
91 
92 #define FOR_EACH_LOAD_BALANCE_ATTR(_attr) \
93  for (_attr = 0; _attr <= LOAD_BALANCE_ATTR_STICKY; _attr++)
94 
95 typedef enum load_balance_flags_t_ {
99 } __attribute__((packed)) load_balance_flags_t;
100 
101 /**
102  * The FIB DPO provieds;
103  * - load-balancing over the next DPOs in the chain/graph
104  * - per-route counters
105  */
106 typedef struct load_balance_t_ {
107  /**
108  * required for pool_get_aligned.
109  * memebers used in the switch path come first!
110  */
111  CLIB_CACHE_LINE_ALIGN_MARK(cacheline0);
112 
113  /**
114  * number of buckets in the load-balance. always a power of 2.
115  */
117  /**
118  * number of buckets in the load-balance - 1. used in the switch path
119  * as part of the hash calculation.
120  */
122 
123  /**
124  * The protocol of packets that traverse this LB.
125  * need in combination with the flow hash config to determine how to hash.
126  * u8.
127  */
129 
130  /**
131  * Flags concenring the LB's creation and modification
132  */
133  load_balance_flags_t lb_flags;
134 
135  /**
136  * Flags from the load-balance's associated fib_entry_t
137  */
139 
140  /**
141  * The number of locks, which is approximately the number of users,
142  * of this load-balance.
143  * Load-balance objects of via-entries are heavily shared by recursives,
144  * so the lock count is a u32.
145  */
147 
148  /**
149  * index of the load-balance map, INVALID if this LB does not use one
150  */
152 
153  /**
154  * This is the index of the uRPF list for this LB
155  */
157 
158  /**
159  * the hash config to use when selecting a bucket. this is a u16
160  */
162 
163  /**
164  * Vector of buckets containing the next DPOs, sized as lbo_num
165  */
167 
168  /**
169  * The rest of the cache line is used for buckets. In the common case
170  * where there there are less than 4 buckets, then the buckets are
171  * on the same cachlie and we save ourselves a pointer dereferance in
172  * the data-path.
173  */
174  dpo_id_t lb_buckets_inline[LB_NUM_INLINE_BUCKETS];
176 
178  "A load_balance object size exceeds one cachline");
179 
180 /**
181  * Flags controlling load-balance formatting/display
182  */
187 
188 extern index_t load_balance_create(u32 num_buckets,
189  dpo_proto_t lb_proto,
190  flow_hash_config_t fhc);
192  const dpo_id_t *dpo,
193  const load_balance_path_t * raw_next_hops,
195 
196 extern void load_balance_set_bucket(index_t lbi,
197  u32 bucket,
198  const dpo_id_t *next);
199 extern void load_balance_set_urpf(index_t lbi,
200  index_t urpf);
204 
205 extern u8* format_load_balance(u8 * s, va_list * args);
206 
207 extern const dpo_id_t *load_balance_get_bucket(index_t lbi,
208  u32 bucket);
209 extern int load_balance_is_drop(const dpo_id_t *dpo);
211 
213 
214 /**
215  * The encapsulation breakages are for fast DP access
216  */
218 static inline load_balance_t*
220 {
221  return (pool_elt_at_index(load_balance_pool, lbi));
222 }
223 
224 #define LB_HAS_INLINE_BUCKETS(_lb) \
225  ((_lb)->lb_n_buckets <= LB_NUM_INLINE_BUCKETS)
226 
227 static inline const dpo_id_t *
229  u32 bucket)
230 {
231  ASSERT(bucket < lb->lb_n_buckets);
232 
234  {
235  return (&lb->lb_buckets_inline[bucket]);
236  }
237  else
238  {
239  return (&lb->lb_buckets[bucket]);
240  }
241 }
242 
243 extern void load_balance_module_init(void);
244 
245 #endif
u16 lb_n_buckets
number of buckets in the load-balance.
Definition: load_balance.h:116
index_t load_balance_get_urpf(index_t lbi)
Definition: load_balance.c:307
dpo_id_t * lb_buckets
Vector of buckets containing the next DPOs, sized as lbo_num.
Definition: load_balance.h:166
void load_balance_multipath_update(const dpo_id_t *dpo, const load_balance_path_t *raw_next_hops, load_balance_flags_t flags)
Definition: load_balance.c:580
vlib_combined_counter_main_t lbm_to_counters
Definition: load_balance.h:46
fib_entry_flag_t lb_fib_entry_flags
Flags from the load-balance&#39;s associated fib_entry_t.
Definition: load_balance.h:138
STATIC_ASSERT(sizeof(load_balance_t)<=CLIB_CACHE_LINE_BYTES,"A load_balance object size exceeds one cachline")
#define CLIB_CACHE_LINE_ALIGN_MARK(mark)
Definition: cache.h:60
u32 flags
Definition: vhost_user.h:115
fib_node_index_t path_index
The index of the FIB path.
Definition: load_balance.h:71
dpo_id_t path_dpo
ID of the Data-path object.
Definition: load_balance.h:66
void load_balance_module_init(void)
Definition: load_balance.c:933
load_balance_main_t load_balance_main
The one instance of load-balance main.
Definition: load_balance.c:55
#define PREDICT_TRUE(x)
Definition: clib.h:112
enum load_balance_format_flags_t_ load_balance_format_flags_t
Flags controlling load-balance formatting/display.
Definitions for all things IP (v4|v6) unicast and multicast lookup related.
f64 load_balance_get_multipath_tolerance(void)
Definition: load_balance.c:67
flow_hash_config_t lb_hash_config
the hash config to use when selecting a bucket.
Definition: load_balance.h:161
void load_balance_set_bucket(index_t lbi, u32 bucket, const dpo_id_t *next)
Definition: load_balance.c:234
load_balance_format_flags_t_
Flags controlling load-balance formatting/display.
Definition: load_balance.h:183
u32 index_t
A Data-Path Object is an object that represents actions that are applied to packets are they are swit...
Definition: dpo.h:41
load_balance_flags_t lb_flags
Flags concenring the LB&#39;s creation and modification.
Definition: load_balance.h:133
void load_balance_set_fib_entry_flags(index_t lbi, fib_entry_flag_t flags)
Definition: load_balance.c:277
unsigned char u8
Definition: types.h:56
double f64
Definition: types.h:142
load_balance_attr_t_
Flags controlling load-balance creation and modification.
Definition: load_balance.h:82
const dpo_id_t * load_balance_get_bucket(index_t lbi, u32 bucket)
Definition: load_balance.c:317
u16 lb_n_buckets_minus_1
number of buckets in the load-balance - 1.
Definition: load_balance.h:121
load_balance_flags_t_
Definition: load_balance.h:95
unsigned int u32
Definition: types.h:88
void load_balance_set_urpf(index_t lbi, index_t urpf)
Definition: load_balance.c:288
enum dpo_proto_t_ dpo_proto_t
Data path protocol.
The identity of a DPO is a combination of its type and its instance number/index of objects of that t...
Definition: dpo.h:168
#define pool_elt_at_index(p, i)
Returns pointer to element at given index.
Definition: pool.h:514
static const dpo_id_t * load_balance_get_bucket_i(const load_balance_t *lb, u32 bucket)
Definition: load_balance.h:228
dpo_proto_t lb_proto
The protocol of packets that traverse this LB.
Definition: load_balance.h:128
unsigned short u16
Definition: types.h:57
The FIB DPO provieds;.
Definition: load_balance.h:106
struct load_balance_main_t_ load_balance_main_t
The load-balance object represents an ECMP choice.
The load-balance object represents an ECMP choice.
Definition: load_balance.h:44
dpo_id_t lb_buckets_inline[LB_NUM_INLINE_BUCKETS]
The rest of the cache line is used for buckets.
Definition: load_balance.h:174
enum load_balance_attr_t_ load_balance_attr_t
Flags controlling load-balance creation and modification.
u32 fib_node_index_t
A typedef of a node index.
Definition: fib_types.h:30
index_t load_balance_create(u32 num_buckets, dpo_proto_t lb_proto, flow_hash_config_t fhc)
Definition: load_balance.c:217
#define LB_NUM_INLINE_BUCKETS
The number of buckets that a load-balance object can have and still fit in one cache-line.
Definition: load_balance.h:56
vlib_combined_counter_main_t lbm_via_counters
Definition: load_balance.h:47
enum fib_entry_flag_t_ fib_entry_flag_t
u8 * format_load_balance(u8 *s, va_list *args)
Definition: load_balance.c:174
#define ASSERT(truth)
index_t lb_urpf
This is the index of the uRPF list for this LB.
Definition: load_balance.h:156
static load_balance_t * load_balance_get(index_t lbi)
Definition: load_balance.h:219
load_balance_t * load_balance_pool
The encapsulation breakages are for fast DP access.
Definition: load_balance.c:50
u32 lb_locks
The number of locks, which is approximately the number of users, of this load-balance.
Definition: load_balance.h:146
struct load_balance_path_t_ load_balance_path_t
One path from an [EU]CMP set that the client wants to add to a load-balance object.
struct load_balance_t_ load_balance_t
The FIB DPO provieds;.
#define LB_HAS_INLINE_BUCKETS(_lb)
Definition: load_balance.h:224
u32 flow_hash_config_t
A flow hash configuration is a mask of the flow hash options.
Definition: lookup.h:84
enum load_balance_flags_t_ load_balance_flags_t
u32 path_weight
weight for the path.
Definition: load_balance.h:76
u16 load_balance_n_buckets(index_t lbi)
Definition: load_balance.c:267
One path from an [EU]CMP set that the client wants to add to a load-balance object.
Definition: load_balance.h:62
A collection of combined counters.
Definition: counter.h:188
index_t lb_map
index of the load-balance map, INVALID if this LB does not use one
Definition: load_balance.h:151
#define CLIB_CACHE_LINE_BYTES
Definition: cache.h:59
int load_balance_is_drop(const dpo_id_t *dpo)
Definition: load_balance.c:250