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:
7 * http://www.apache.org/licenses/LICENSE-2.0
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.
16 #include <vnet/ip/lookup.h>
17 #include <vnet/dpo/load_balance.h>
18 #include <vnet/dpo/load_balance_map.h>
19 #include <vnet/dpo/drop_dpo.h>
20 #include <vppinfra/math.h> /* for fabs */
21 #include <vnet/adj/adj.h>
22 #include <vnet/adj/adj_internal.h>
23 #include <vnet/fib/fib_urpf_list.h>
26 * distribution error tolerance for load-balancing
28 const f64 multipath_next_hop_error_tolerance = 0.1;
33 #define LB_DBG(_lb, _fmt, _args...) \
36 clib_warning("lb:[%s]:" _fmt, \
37 load_balance_format(load_balance_get_index((_lb)), \
43 #define LB_DBG(_p, _fmt, _args...)
48 * Pool of all DPOs. It's not static so the DP can have fast access
50 load_balance_t *load_balance_pool;
53 * The one instance of load-balance main
55 load_balance_main_t load_balance_main;
58 load_balance_get_multipath_tolerance (void)
60 return (multipath_next_hop_error_tolerance);
64 load_balance_get_index (const load_balance_t *lb)
66 return (lb - load_balance_pool);
69 static inline dpo_id_t*
70 load_balance_get_buckets (load_balance_t *lb)
72 if (LB_HAS_INLINE_BUCKETS(lb))
74 return (lb->lb_buckets_inline);
78 return (lb->lb_buckets);
82 static load_balance_t *
83 load_balance_alloc_i (void)
87 pool_get_aligned(load_balance_pool, lb, CLIB_CACHE_LINE_BYTES);
88 memset(lb, 0, sizeof(*lb));
90 lb->lb_map = INDEX_INVALID;
91 lb->lb_urpf = INDEX_INVALID;
92 vlib_validate_combined_counter(&(load_balance_main.lbm_to_counters),
93 load_balance_get_index(lb));
94 vlib_validate_combined_counter(&(load_balance_main.lbm_via_counters),
95 load_balance_get_index(lb));
96 vlib_zero_combined_counter(&(load_balance_main.lbm_to_counters),
97 load_balance_get_index(lb));
98 vlib_zero_combined_counter(&(load_balance_main.lbm_via_counters),
99 load_balance_get_index(lb));
105 load_balance_format (index_t lbi,
106 load_balance_format_flags_t flags,
110 vlib_counter_t to, via;
115 lb = load_balance_get(lbi);
116 vlib_get_combined_counter(&(load_balance_main.lbm_to_counters), lbi, &to);
117 vlib_get_combined_counter(&(load_balance_main.lbm_via_counters), lbi, &via);
118 buckets = load_balance_get_buckets(lb);
120 s = format(s, "%U: ", format_dpo_type, DPO_LOAD_BALANCE);
121 s = format(s, "[proto:%U ", format_dpo_proto, lb->lb_proto);
122 s = format(s, "index:%d buckets:%d ", lbi, lb->lb_n_buckets);
123 s = format(s, "uRPF:%d ", lb->lb_urpf);
124 s = format(s, "to:[%Ld:%Ld]", to.packets, to.bytes);
125 if (0 != via.packets)
127 s = format(s, " via:[%Ld:%Ld]",
128 via.packets, via.bytes);
132 if (INDEX_INVALID != lb->lb_map)
134 s = format(s, "\n%U%U",
135 format_white_space, indent+4,
136 format_load_balance_map, lb->lb_map, indent+4);
138 for (i = 0; i < lb->lb_n_buckets; i++)
140 s = format(s, "\n%U[%d] %U",
141 format_white_space, indent+2,
144 &buckets[i], indent+6);
150 format_load_balance (u8 * s, va_list * args)
152 index_t lbi = va_arg(*args, index_t);
153 load_balance_format_flags_t flags = va_arg(*args, load_balance_format_flags_t);
155 return (load_balance_format(lbi, flags, 0, s));
158 format_load_balance_dpo (u8 * s, va_list * args)
160 index_t lbi = va_arg(*args, index_t);
161 u32 indent = va_arg(*args, u32);
163 return (load_balance_format(lbi, LOAD_BALANCE_FORMAT_DETAIL, indent, s));
167 static load_balance_t *
168 load_balance_create_i (u32 num_buckets,
169 dpo_proto_t lb_proto,
170 flow_hash_config_t fhc)
174 lb = load_balance_alloc_i();
175 lb->lb_hash_config = fhc;
176 lb->lb_n_buckets = num_buckets;
177 lb->lb_n_buckets_minus_1 = num_buckets-1;
178 lb->lb_proto = lb_proto;
180 if (!LB_HAS_INLINE_BUCKETS(lb))
182 vec_validate_aligned(lb->lb_buckets,
183 lb->lb_n_buckets - 1,
184 CLIB_CACHE_LINE_BYTES);
187 LB_DBG(lb, "create");
193 load_balance_create (u32 n_buckets,
194 dpo_proto_t lb_proto,
195 flow_hash_config_t fhc)
197 return (load_balance_get_index(load_balance_create_i(n_buckets, lb_proto, fhc)));
201 load_balance_set_bucket_i (load_balance_t *lb,
204 const dpo_id_t *next)
206 dpo_stack(DPO_LOAD_BALANCE, lb->lb_proto, &buckets[bucket], next);
210 load_balance_set_bucket (index_t lbi,
212 const dpo_id_t *next)
217 lb = load_balance_get(lbi);
218 buckets = load_balance_get_buckets(lb);
220 ASSERT(bucket < lb->lb_n_buckets);
222 load_balance_set_bucket_i(lb, bucket, buckets, next);
226 load_balance_is_drop (const dpo_id_t *dpo)
230 if (DPO_LOAD_BALANCE != dpo->dpoi_type)
233 lb = load_balance_get(dpo->dpoi_index);
235 if (1 == lb->lb_n_buckets)
237 return (dpo_is_drop(load_balance_get_bucket_i(lb, 0)));
243 load_balance_set_fib_entry_flags (index_t lbi,
244 fib_entry_flag_t flags)
248 lb = load_balance_get(lbi);
249 lb->lb_fib_entry_flags = flags;
254 load_balance_set_urpf (index_t lbi,
260 lb = load_balance_get(lbi);
263 * packets in flight we see this change. but it's atomic, so :P
268 fib_urpf_list_unlock(old);
269 fib_urpf_list_lock(urpf);
273 load_balance_get_urpf (index_t lbi)
277 lb = load_balance_get(lbi);
279 return (lb->lb_urpf);
283 load_balance_get_bucket (index_t lbi,
288 lb = load_balance_get(lbi);
290 return (load_balance_get_bucket_i(lb, bucket));
294 next_hop_sort_by_weight (const load_balance_path_t * n1,
295 const load_balance_path_t * n2)
297 return ((int) n1->path_weight - (int) n2->path_weight);
300 /* Given next hop vector is over-written with normalized one with sorted weights and
301 with weights corresponding to the number of adjacencies for each next hop.
302 Returns number of adjacencies in block. */
304 ip_multipath_normalize_next_hops (const load_balance_path_t * raw_next_hops,
305 load_balance_path_t ** normalized_next_hops,
307 f64 multipath_next_hop_error_tolerance)
309 load_balance_path_t * nhs;
310 uword n_nhs, n_adj, n_adj_left, i, sum_weight;
313 n_nhs = vec_len (raw_next_hops);
318 /* Allocate enough space for 2 copies; we'll use second copy to save original weights. */
319 nhs = *normalized_next_hops;
320 vec_validate (nhs, 2*n_nhs - 1);
322 /* Fast path: 1 next hop in block. */
326 nhs[0] = raw_next_hops[0];
327 nhs[0].path_weight = 1;
335 int cmp = next_hop_sort_by_weight (&raw_next_hops[0], &raw_next_hops[1]) < 0;
338 nhs[0] = raw_next_hops[cmp];
339 nhs[1] = raw_next_hops[cmp ^ 1];
341 /* Fast path: equal cost multipath with 2 next hops. */
342 if (nhs[0].path_weight == nhs[1].path_weight)
344 nhs[0].path_weight = nhs[1].path_weight = 1;
352 clib_memcpy (nhs, raw_next_hops, n_nhs * sizeof (raw_next_hops[0]));
353 qsort (nhs, n_nhs, sizeof (nhs[0]), (void *) next_hop_sort_by_weight);
356 /* Find total weight to normalize weights. */
358 for (i = 0; i < n_nhs; i++)
359 sum_weight += nhs[i].path_weight;
361 /* In the unlikely case that all weights are given as 0, set them all to 1. */
364 for (i = 0; i < n_nhs; i++)
365 nhs[i].path_weight = 1;
369 /* Save copies of all next hop weights to avoid being overwritten in loop below. */
370 for (i = 0; i < n_nhs; i++)
371 nhs[n_nhs + i].path_weight = nhs[i].path_weight;
373 /* Try larger and larger power of 2 sized adjacency blocks until we
374 find one where traffic flows to within 1% of specified weights. */
375 for (n_adj = max_pow2 (n_nhs); ; n_adj *= 2)
379 norm = n_adj / ((f64) sum_weight);
381 for (i = 0; i < n_nhs; i++)
383 f64 nf = nhs[n_nhs + i].path_weight * norm; /* use saved weights */
384 word n = flt_round_nearest (nf);
386 n = n > n_adj_left ? n_adj_left : n;
388 error += fabs (nf - n);
389 nhs[i].path_weight = n;
391 if (0 == nhs[i].path_weight)
394 * when the weight skew is high (norm is small) and n == nf.
395 * without this correction the path with a low weight would have
396 * no represenation in the load-balanace - don't want that.
397 * If the weight skew is high so the load-balance has many buckets
398 * to allow it. pays ya money takes ya choice.
405 nhs[0].path_weight += n_adj_left;
407 /* Less than 5% average error per adjacency with this size adjacency block? */
408 if (error <= multipath_next_hop_error_tolerance*n_adj)
410 /* Truncate any next hops with zero weight. */
417 /* Save vector for next call. */
418 *normalized_next_hops = nhs;
419 *sum_weight_in = sum_weight;
423 static load_balance_path_t *
424 load_balance_multipath_next_hop_fixup (const load_balance_path_t *nhs,
425 dpo_proto_t drop_proto)
427 if (0 == vec_len(nhs))
429 load_balance_path_t *new_nhs = NULL, *nh;
432 * we need something for the load-balance. so use the drop
434 vec_add2(new_nhs, nh, 1);
437 dpo_copy(&nh->path_dpo, drop_dpo_get(drop_proto));
446 * Fill in adjacencies in block based on corresponding
447 * next hop adjacencies.
450 load_balance_fill_buckets (load_balance_t *lb,
451 load_balance_path_t *nhs,
455 load_balance_path_t * nh;
461 * the next-hops have normalised weights. that means their sum is the number
462 * of buckets we need to fill.
464 vec_foreach (nh, nhs)
466 for (ii = 0; ii < nh->path_weight; ii++)
468 ASSERT(bucket < n_buckets);
469 load_balance_set_bucket_i(lb, bucket++, buckets, &nh->path_dpo);
475 load_balance_set_n_buckets (load_balance_t *lb,
478 lb->lb_n_buckets = n_buckets;
479 lb->lb_n_buckets_minus_1 = n_buckets-1;
483 load_balance_multipath_update (const dpo_id_t *dpo,
484 const load_balance_path_t * raw_nhs,
485 load_balance_flags_t flags)
487 load_balance_path_t *nh, *nhs, *fixed_nhs;
488 u32 sum_of_weights, n_buckets, ii;
489 index_t lbmi, old_lbmi;
495 ASSERT(DPO_LOAD_BALANCE == dpo->dpoi_type);
496 lb = load_balance_get(dpo->dpoi_index);
497 fixed_nhs = load_balance_multipath_next_hop_fixup(raw_nhs, lb->lb_proto);
499 ip_multipath_normalize_next_hops((NULL == fixed_nhs ?
504 multipath_next_hop_error_tolerance);
506 ASSERT (n_buckets >= vec_len (raw_nhs));
509 * Save the old load-balance map used, and get a new one if required.
511 old_lbmi = lb->lb_map;
512 if (flags & LOAD_BALANCE_FLAG_USES_MAP)
514 lbmi = load_balance_map_add_or_lock(n_buckets, sum_of_weights, nhs);
518 lbmi = INDEX_INVALID;
521 if (0 == lb->lb_n_buckets)
524 * first time initialisation. no packets inflight, so we can write
527 load_balance_set_n_buckets(lb, n_buckets);
529 if (!LB_HAS_INLINE_BUCKETS(lb))
530 vec_validate_aligned(lb->lb_buckets,
531 lb->lb_n_buckets - 1,
532 CLIB_CACHE_LINE_BYTES);
534 load_balance_fill_buckets(lb, nhs,
535 load_balance_get_buckets(lb),
542 * This is a modification of an existing load-balance.
543 * We need to ensure that packets inflight see a consistent state, that
544 * is the number of reported buckets the LB has (read from
545 * lb_n_buckets_minus_1) is not more than it actually has. So if the
546 * number of buckets is increasing, we must update the bucket array first,
547 * then the reported number. vice-versa if the number of buckets goes down.
549 if (n_buckets == lb->lb_n_buckets)
552 * no change in the number of buckets. we can simply fill what
553 * is new over what is old.
555 load_balance_fill_buckets(lb, nhs,
556 load_balance_get_buckets(lb),
560 else if (n_buckets > lb->lb_n_buckets)
563 * we have more buckets. the old load-balance map (if there is one)
564 * will remain valid, i.e. mapping to indices within range, so we
567 if (n_buckets > LB_NUM_INLINE_BUCKETS &&
568 lb->lb_n_buckets <= LB_NUM_INLINE_BUCKETS)
571 * the new increased number of buckets is crossing the threshold
572 * from the inline storage to out-line. Alloc the outline buckets
573 * first, then fixup the number. then reset the inlines.
575 ASSERT(NULL == lb->lb_buckets);
576 vec_validate_aligned(lb->lb_buckets,
578 CLIB_CACHE_LINE_BYTES);
580 load_balance_fill_buckets(lb, nhs,
583 CLIB_MEMORY_BARRIER();
584 load_balance_set_n_buckets(lb, n_buckets);
586 CLIB_MEMORY_BARRIER();
588 for (ii = 0; ii < LB_NUM_INLINE_BUCKETS; ii++)
590 dpo_reset(&lb->lb_buckets_inline[ii]);
595 if (n_buckets <= LB_NUM_INLINE_BUCKETS)
598 * we are not crossing the threshold and it's still inline buckets.
599 * we can write the new on the old..
601 load_balance_fill_buckets(lb, nhs,
602 load_balance_get_buckets(lb),
604 CLIB_MEMORY_BARRIER();
605 load_balance_set_n_buckets(lb, n_buckets);
610 * we are not crossing the threshold. We need a new bucket array to
611 * hold the increased number of choices.
613 dpo_id_t *new_buckets, *old_buckets, *tmp_dpo;
616 old_buckets = load_balance_get_buckets(lb);
618 vec_validate_aligned(new_buckets,
620 CLIB_CACHE_LINE_BYTES);
622 load_balance_fill_buckets(lb, nhs, new_buckets, n_buckets);
623 CLIB_MEMORY_BARRIER();
624 lb->lb_buckets = new_buckets;
625 CLIB_MEMORY_BARRIER();
626 load_balance_set_n_buckets(lb, n_buckets);
628 vec_foreach(tmp_dpo, old_buckets)
632 vec_free(old_buckets);
637 * buckets fixed. ready for the MAP update.
644 * bucket size shrinkage.
645 * Any map we have will be based on the old
646 * larger number of buckets, so will be translating to indices
647 * out of range. So the new MAP must be installed first.
650 CLIB_MEMORY_BARRIER();
653 if (n_buckets <= LB_NUM_INLINE_BUCKETS &&
654 lb->lb_n_buckets > LB_NUM_INLINE_BUCKETS)
657 * the new decreased number of buckets is crossing the threshold
658 * from out-line storage to inline:
659 * 1 - Fill the inline buckets,
660 * 2 - fixup the number (and this point the inline buckets are
662 * 3 - free the outline buckets
664 load_balance_fill_buckets(lb, nhs,
665 lb->lb_buckets_inline,
667 CLIB_MEMORY_BARRIER();
668 load_balance_set_n_buckets(lb, n_buckets);
669 CLIB_MEMORY_BARRIER();
671 vec_foreach(tmp_dpo, lb->lb_buckets)
675 vec_free(lb->lb_buckets);
680 * not crossing the threshold.
681 * 1 - update the number to the smaller size
682 * 2 - write the new buckets
683 * 3 - reset those no longer used.
688 old_n_buckets = lb->lb_n_buckets;
689 buckets = load_balance_get_buckets(lb);
691 load_balance_set_n_buckets(lb, n_buckets);
692 CLIB_MEMORY_BARRIER();
694 load_balance_fill_buckets(lb, nhs,
698 for (ii = n_buckets; ii < old_n_buckets; ii++)
700 dpo_reset(&buckets[ii]);
706 vec_foreach (nh, nhs)
708 dpo_reset(&nh->path_dpo);
713 load_balance_map_unlock(old_lbmi);
717 load_balance_lock (dpo_id_t *dpo)
721 lb = load_balance_get(dpo->dpoi_index);
727 load_balance_destroy (load_balance_t *lb)
732 buckets = load_balance_get_buckets(lb);
734 for (i = 0; i < lb->lb_n_buckets; i++)
736 dpo_reset(&buckets[i]);
739 LB_DBG(lb, "destroy");
740 if (!LB_HAS_INLINE_BUCKETS(lb))
742 vec_free(lb->lb_buckets);
745 fib_urpf_list_unlock(lb->lb_urpf);
746 load_balance_map_unlock(lb->lb_map);
748 pool_put(load_balance_pool, lb);
752 load_balance_unlock (dpo_id_t *dpo)
756 lb = load_balance_get(dpo->dpoi_index);
760 if (0 == lb->lb_locks)
762 load_balance_destroy(lb);
767 load_balance_mem_show (void)
769 fib_show_memory_usage("load-balance",
770 pool_elts(load_balance_pool),
771 pool_len(load_balance_pool),
772 sizeof(load_balance_t));
773 load_balance_map_show_mem();
776 const static dpo_vft_t lb_vft = {
777 .dv_lock = load_balance_lock,
778 .dv_unlock = load_balance_unlock,
779 .dv_format = format_load_balance_dpo,
780 .dv_mem_show = load_balance_mem_show,
784 * @brief The per-protocol VLIB graph nodes that are assigned to a load-balance
787 * this means that these graph nodes are ones from which a load-balance is the
788 * parent object in the DPO-graph.
790 * We do not list all the load-balance nodes, such as the *-lookup. instead
791 * we are relying on the correct use of the .sibling_of field when setting
792 * up these sibling nodes.
794 const static char* const load_balance_ip4_nodes[] =
799 const static char* const load_balance_ip6_nodes[] =
804 const static char* const load_balance_mpls_nodes[] =
809 const static char* const load_balance_l2_nodes[] =
814 const static char* const load_balance_nsh_nodes[] =
819 const static char* const * const load_balance_nodes[DPO_PROTO_NUM] =
821 [DPO_PROTO_IP4] = load_balance_ip4_nodes,
822 [DPO_PROTO_IP6] = load_balance_ip6_nodes,
823 [DPO_PROTO_MPLS] = load_balance_mpls_nodes,
824 [DPO_PROTO_ETHERNET] = load_balance_l2_nodes,
825 [DPO_PROTO_NSH] = load_balance_nsh_nodes,
829 load_balance_module_init (void)
833 dpo_register(DPO_LOAD_BALANCE, &lb_vft, load_balance_nodes);
836 * Special LB with index zero. we need to define this since the v4 mtrie
837 * assumes an index of 0 implies the ply is empty. therefore all 'real'
838 * adjs need a non-zero index.
839 * This should never be used, but just in case, stack it on a drop.
841 lbi = load_balance_create(1, DPO_PROTO_IP4, 0);
842 load_balance_set_bucket(lbi, 0, drop_dpo_get(DPO_PROTO_IP4));
844 load_balance_map_module_init();
847 static clib_error_t *
848 load_balance_show (vlib_main_t * vm,
849 unformat_input_t * input,
850 vlib_cli_command_t * cmd)
852 index_t lbi = INDEX_INVALID;
854 while (unformat_check_input (input) != UNFORMAT_END_OF_INPUT)
856 if (unformat (input, "%d", &lbi))
862 if (INDEX_INVALID != lbi)
864 vlib_cli_output (vm, "%U", format_load_balance, lbi,
865 LOAD_BALANCE_FORMAT_DETAIL);
871 pool_foreach(lb, load_balance_pool,
873 vlib_cli_output (vm, "%U", format_load_balance,
874 load_balance_get_index(lb),
875 LOAD_BALANCE_FORMAT_NONE);
882 VLIB_CLI_COMMAND (load_balance_show_command, static) = {
883 .path = "show load-balance",
884 .short_help = "show load-balance [<index>]",
885 .function = load_balance_show,
890 ip_flow_hash (void *data)
892 ip4_header_t *iph = (ip4_header_t *) data;
894 if ((iph->ip_version_and_header_length & 0xF0) == 0x40)
895 return ip4_compute_flow_hash (iph, IP_FLOW_HASH_DEFAULT);
897 return ip6_compute_flow_hash ((ip6_header_t *) iph, IP_FLOW_HASH_DEFAULT);
903 return (*((u64 *) m) & 0xffffffffffff);
907 l2_flow_hash (vlib_buffer_t * b0)
909 ethernet_header_t *eh;
911 uword is_ip, eh_size;
914 eh = vlib_buffer_get_current (b0);
915 eh_type = clib_net_to_host_u16 (eh->type);
916 eh_size = ethernet_buffer_header_size (b0);
918 is_ip = (eh_type == ETHERNET_TYPE_IP4 || eh_type == ETHERNET_TYPE_IP6);
920 /* since we have 2 cache lines, use them */
922 a = ip_flow_hash ((u8 *) vlib_buffer_get_current (b0) + eh_size);
926 b = mac_to_u64 ((u8 *) eh->dst_address);
927 c = mac_to_u64 ((u8 *) eh->src_address);
928 hash_mix64 (a, b, c);
933 typedef struct load_balance_trace_t_
936 } load_balance_trace_t;
939 l2_load_balance (vlib_main_t * vm,
940 vlib_node_runtime_t * node,
941 vlib_frame_t * frame)
943 u32 n_left_from, next_index, *from, *to_next;
945 from = vlib_frame_vector_args (frame);
946 n_left_from = frame->n_vectors;
948 next_index = node->cached_next_index;
950 while (n_left_from > 0)
954 vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
956 while (n_left_from > 0 && n_left_to_next > 0)
959 u32 bi0, lbi0, next0;
960 const dpo_id_t *dpo0;
961 const load_balance_t *lb0;
970 b0 = vlib_get_buffer (vm, bi0);
972 /* lookup dst + src mac */
973 lbi0 = vnet_buffer (b0)->ip.adj_index[VLIB_TX];
974 lb0 = load_balance_get(lbi0);
976 vnet_buffer(b0)->ip.flow_hash = l2_flow_hash(b0);
978 dpo0 = load_balance_get_bucket_i(lb0,
979 vnet_buffer(b0)->ip.flow_hash &
980 (lb0->lb_n_buckets_minus_1));
982 next0 = dpo0->dpoi_next_node;
983 vnet_buffer (b0)->ip.adj_index[VLIB_TX] = dpo0->dpoi_index;
985 if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
987 load_balance_trace_t *tr = vlib_add_trace (vm, node, b0,
991 vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next,
992 n_left_to_next, bi0, next0);
995 vlib_put_next_frame (vm, node, next_index, n_left_to_next);
998 return frame->n_vectors;
1002 format_l2_load_balance_trace (u8 * s, va_list * args)
1004 CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
1005 CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
1006 load_balance_trace_t *t = va_arg (*args, load_balance_trace_t *);
1008 s = format (s, "L2-load-balance: index %d", t->lb_index);
1015 VLIB_REGISTER_NODE (l2_load_balance_node) = {
1016 .function = l2_load_balance,
1017 .name = "l2-load-balance",
1018 .vector_size = sizeof (u32),
1020 .format_trace = format_l2_load_balance_trace,
1028 nsh_load_balance (vlib_main_t * vm,
1029 vlib_node_runtime_t * node,
1030 vlib_frame_t * frame)
1032 u32 n_left_from, next_index, *from, *to_next;
1034 from = vlib_frame_vector_args (frame);
1035 n_left_from = frame->n_vectors;
1037 next_index = node->cached_next_index;
1039 while (n_left_from > 0)
1043 vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
1045 while (n_left_from > 0 && n_left_to_next > 0)
1048 u32 bi0, lbi0, next0, *nsh0;
1049 const dpo_id_t *dpo0;
1050 const load_balance_t *lb0;
1057 n_left_to_next -= 1;
1059 b0 = vlib_get_buffer (vm, bi0);
1061 lbi0 = vnet_buffer (b0)->ip.adj_index[VLIB_TX];
1062 lb0 = load_balance_get(lbi0);
1064 /* SPI + SI are the second word of the NSH header */
1065 nsh0 = vlib_buffer_get_current (b0);
1066 vnet_buffer(b0)->ip.flow_hash = nsh0[1] % lb0->lb_n_buckets;
1068 dpo0 = load_balance_get_bucket_i(lb0,
1069 vnet_buffer(b0)->ip.flow_hash &
1070 (lb0->lb_n_buckets_minus_1));
1072 next0 = dpo0->dpoi_next_node;
1073 vnet_buffer (b0)->ip.adj_index[VLIB_TX] = dpo0->dpoi_index;
1075 if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
1077 load_balance_trace_t *tr = vlib_add_trace (vm, node, b0,
1079 tr->lb_index = lbi0;
1081 vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next,
1082 n_left_to_next, bi0, next0);
1085 vlib_put_next_frame (vm, node, next_index, n_left_to_next);
1088 return frame->n_vectors;
1092 format_nsh_load_balance_trace (u8 * s, va_list * args)
1094 CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
1095 CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
1096 load_balance_trace_t *t = va_arg (*args, load_balance_trace_t *);
1098 s = format (s, "NSH-load-balance: index %d", t->lb_index);
1105 VLIB_REGISTER_NODE (nsh_load_balance_node) = {
1106 .function = nsh_load_balance,
1107 .name = "nsh-load-balance",
1108 .vector_size = sizeof (u32),
1110 .format_trace = format_nsh_load_balance_trace,