FD.io VPP  v19.04.2-12-g66b1689
Vector Packet Processing
adj_nbr.c
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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 #include <vnet/adj/adj_nbr.h>
17 #include <vnet/adj/adj_internal.h>
19 #include <vnet/fib/fib_walk.h>
20 
21 #include <vppinfra/bihash_24_8.h>
22 
23 /*
24  * Vector Hash tables of neighbour (traditional) adjacencies
25  * Key: interface(for the vector index), address (and its proto),
26  * link-type/ether-type.
27  */
28 static BVT(clib_bihash) **adj_nbr_tables[FIB_PROTOCOL_MAX];
29 
30 // FIXME SIZE APPROPRIATELY. ASK DAVEB.
31 #define ADJ_NBR_DEFAULT_HASH_NUM_BUCKETS (64 * 64)
32 #define ADJ_NBR_DEFAULT_HASH_MEMORY_SIZE (32<<20)
33 
34 
35 #define ADJ_NBR_SET_KEY(_key, _lt, _nh) \
36 { \
37  _key.key[0] = (_nh)->as_u64[0]; \
38  _key.key[1] = (_nh)->as_u64[1]; \
39  _key.key[2] = (_lt); \
40 }
41 
42 #define ADJ_NBR_ITF_OK(_proto, _itf) \
43  (((_itf) < vec_len(adj_nbr_tables[_proto])) && \
44  (NULL != adj_nbr_tables[_proto][sw_if_index]))
45 
46 static void
47 adj_nbr_insert (fib_protocol_t nh_proto,
48  vnet_link_t link_type,
49  const ip46_address_t *nh_addr,
51  adj_index_t adj_index)
52 {
53  BVT(clib_bihash_kv) kv;
54 
55  if (sw_if_index >= vec_len(adj_nbr_tables[nh_proto]))
56  {
57  vec_validate(adj_nbr_tables[nh_proto], sw_if_index);
58  }
59  if (NULL == adj_nbr_tables[nh_proto][sw_if_index])
60  {
61  adj_nbr_tables[nh_proto][sw_if_index] =
62  clib_mem_alloc_aligned(sizeof(BVT(clib_bihash)),
64  clib_memset(adj_nbr_tables[nh_proto][sw_if_index],
65  0,
66  sizeof(BVT(clib_bihash)));
67 
68  BV(clib_bihash_init) (adj_nbr_tables[nh_proto][sw_if_index],
69  "Adjacency Neighbour table",
72  }
73 
74  ADJ_NBR_SET_KEY(kv, link_type, nh_addr);
75  kv.value = adj_index;
76 
77  BV(clib_bihash_add_del) (adj_nbr_tables[nh_proto][sw_if_index], &kv, 1);
78 }
79 
80 void
82  fib_protocol_t nh_proto,
83  vnet_link_t link_type,
84  const ip46_address_t *nh_addr,
86 {
87  BVT(clib_bihash_kv) kv;
88 
89  if (!ADJ_NBR_ITF_OK(nh_proto, sw_if_index))
90  return;
91 
92  ADJ_NBR_SET_KEY(kv, link_type, nh_addr);
93  kv.value = ai;
94 
95  BV(clib_bihash_add_del) (adj_nbr_tables[nh_proto][sw_if_index], &kv, 0);
96 }
97 
100  vnet_link_t link_type,
101  const ip46_address_t *nh_addr,
103 {
104  BVT(clib_bihash_kv) kv;
105 
106  ADJ_NBR_SET_KEY(kv, link_type, nh_addr);
107 
108  if (!ADJ_NBR_ITF_OK(nh_proto, sw_if_index))
109  return (ADJ_INDEX_INVALID);
110 
111  if (BV(clib_bihash_search)(adj_nbr_tables[nh_proto][sw_if_index],
112  &kv, &kv) < 0)
113  {
114  return (ADJ_INDEX_INVALID);
115  }
116  else
117  {
118  return (kv.value);
119  }
120 }
121 
122 static inline u32
124 {
125  switch (proto) {
126  case FIB_PROTOCOL_IP4:
127  return (ip4_arp_node.index);
128  case FIB_PROTOCOL_IP6:
129  return (ip6_discover_neighbor_node.index);
130  case FIB_PROTOCOL_MPLS:
131  break;
132  }
133  ASSERT(0);
134  return (ip4_arp_node.index);
135 }
136 
137 /**
138  * @brief Check and set feature flags if o/p interface has any o/p features.
139  */
140 static void
142 {
143  ip_adjacency_t *adj;
145  i16 feature_count;
146  u8 arc_index;
148 
149  adj = adj_get(ai);
150 
151  switch (adj->ia_link)
152  {
153  case VNET_LINK_IP4:
155  break;
156  case VNET_LINK_IP6:
158  break;
159  case VNET_LINK_MPLS:
161  break;
162  default:
163  return;
164  }
165 
166  sw_if_index = adj->rewrite_header.sw_if_index;
167  if (vec_len(fm->feature_count_by_sw_if_index[arc_index]) > sw_if_index)
168  {
169  feature_count = fm->feature_count_by_sw_if_index[arc_index][sw_if_index];
170  if (feature_count > 0)
171  adj->rewrite_header.flags |= VNET_REWRITE_HAS_FEATURES;
172  }
173 
174  return;
175 }
176 
177 static ip_adjacency_t*
179  vnet_link_t link_type,
180  const ip46_address_t *nh_addr,
182 {
183  ip_adjacency_t *adj;
184 
185  adj = adj_alloc(nh_proto);
186 
187  adj_nbr_insert(nh_proto, link_type, nh_addr,
188  sw_if_index,
189  adj_get_index(adj));
190 
191  /*
192  * since we just added the ADJ we have no rewrite string for it,
193  * so its for ARP
194  */
196  adj->sub_type.nbr.next_hop = *nh_addr;
197  adj->ia_link = link_type;
198  adj->ia_nh_proto = nh_proto;
199  adj->rewrite_header.sw_if_index = sw_if_index;
201  &adj->rewrite_header);
202 
204  return (adj);
205 }
206 
207 /*
208  * adj_nbr_add_or_lock
209  *
210  * Add an adjacency for the neighbour requested.
211  *
212  * The key for an adj is:
213  * - the Next-hops protocol (i.e. v4 or v6)
214  * - the address of the next-hop
215  * - the interface the next-hop is reachable through
216  */
219  vnet_link_t link_type,
220  const ip46_address_t *nh_addr,
222 {
223  adj_index_t adj_index;
224  ip_adjacency_t *adj;
225 
226  adj_index = adj_nbr_find(nh_proto, link_type, nh_addr, sw_if_index);
227 
228  if (ADJ_INDEX_INVALID == adj_index)
229  {
230  vnet_main_t *vnm;
231 
232  vnm = vnet_get_main();
233  adj = adj_nbr_alloc(nh_proto, link_type, nh_addr, sw_if_index);
234  adj_index = adj_get_index(adj);
235  adj_lock(adj_index);
236 
237  if (ip46_address_is_equal(&ADJ_BCAST_ADDR, nh_addr))
238  {
240  }
241 
242  vnet_rewrite_init(vnm, sw_if_index, link_type,
243  adj_get_nd_node(nh_proto),
244  vnet_tx_node_index_for_sw_interface(vnm, sw_if_index),
245  &adj->rewrite_header);
246 
247  /*
248  * we need a rewrite where the destination IP address is converted
249  * to the appropriate link-layer address. This is interface specific.
250  * So ask the interface to do it.
251  */
252  vnet_update_adjacency_for_sw_interface(vnm, sw_if_index, adj_index);
253  }
254  else
255  {
256  adj_lock(adj_index);
257  }
258 
259  return (adj_index);
260 }
261 
264  vnet_link_t link_type,
265  const ip46_address_t *nh_addr,
267  u8 *rewrite)
268 {
269  adj_index_t adj_index;
270 
271  adj_index = adj_nbr_find(nh_proto, link_type, nh_addr, sw_if_index);
272 
273  if (ADJ_INDEX_INVALID == adj_index)
274  {
275  ip_adjacency_t *adj;
276 
277  adj = adj_nbr_alloc(nh_proto, link_type, nh_addr, sw_if_index);
278  adj->rewrite_header.sw_if_index = sw_if_index;
279  adj_index = adj_get_index(adj);
280  }
281 
282  adj_lock(adj_index);
283  adj_nbr_update_rewrite(adj_index,
285  rewrite);
286 
287  return (adj_index);
288 }
289 
290 /**
291  * adj_nbr_update_rewrite
292  *
293  * Update the adjacency's rewrite string. A NULL string implies the
294  * rewrite is reset (i.e. when ARP/ND entry is gone).
295  * NB: the adj being updated may be handling traffic in the DP.
296  */
297 void
300  u8 *rewrite)
301 {
302  ip_adjacency_t *adj;
303 
304  ASSERT(ADJ_INDEX_INVALID != adj_index);
305 
306  adj = adj_get(adj_index);
307 
308  if (flags & ADJ_NBR_REWRITE_FLAG_COMPLETE)
309  {
310  /*
311  * update the adj's rewrite string and build the arc
312  * from the rewrite node to the interface's TX node
313  */
317  vnet_get_main(),
318  adj->rewrite_header.sw_if_index),
319  rewrite);
320  }
321  else
322  {
326  vnet_get_main(),
327  adj->rewrite_header.sw_if_index),
328  rewrite);
329  }
330 }
331 
332 /**
333  * adj_nbr_update_rewrite_internal
334  *
335  * Update the adjacency's rewrite string. A NULL string implies the
336  * rewrite is reset (i.e. when ARP/ND entry is gone).
337  * NB: the adj being updated may be handling traffic in the DP.
338  */
339 void
341  ip_lookup_next_t adj_next_index,
342  u32 this_node,
343  u32 next_node,
344  u8 *rewrite)
345 {
346  ip_adjacency_t *walk_adj;
347  adj_index_t walk_ai;
348  vlib_main_t * vm;
349  u32 old_next;
350  int do_walk;
351 
352  vm = vlib_get_main();
353  old_next = adj->lookup_next_index;
354 
355  walk_ai = adj_get_index(adj);
356  if (VNET_LINK_MPLS == adj->ia_link)
357  {
358  /*
359  * The link type MPLS has no children in the control plane graph, it only
360  * has children in the data-plane graph. The backwalk is up the former.
361  * So we need to walk from its IP cousin.
362  */
363  walk_ai = adj_nbr_find(adj->ia_nh_proto,
365  &adj->sub_type.nbr.next_hop,
366  adj->rewrite_header.sw_if_index);
367  }
368 
369  /*
370  * Don't call the walk re-entrantly
371  */
372  if (ADJ_INDEX_INVALID != walk_ai)
373  {
374  walk_adj = adj_get(walk_ai);
375  if (ADJ_FLAG_SYNC_WALK_ACTIVE & walk_adj->ia_flags)
376  {
377  do_walk = 0;
378  }
379  else
380  {
381  /*
382  * Prevent re-entrant walk of the same adj
383  */
384  walk_adj->ia_flags |= ADJ_FLAG_SYNC_WALK_ACTIVE;
385  do_walk = 1;
386  }
387  }
388  else
389  {
390  do_walk = 0;
391  }
392 
393  /*
394  * lock the adjacencies that are affected by updates this walk will provoke.
395  * Since the aim of the walk is to update children to link to a different
396  * DPO, this adj will no longer be in use and its lock count will drop to 0.
397  * We don't want it to be deleted as part of this endeavour.
398  */
399  adj_lock(adj_get_index(adj));
400  adj_lock(walk_ai);
401 
402  /*
403  * Updating a rewrite string is not atomic;
404  * - the rewrite string is too long to write in one instruction
405  * - when swapping from incomplete to complete, we also need to update
406  * the VLIB graph next-index of the adj.
407  * ideally we would only want to suspend forwarding via this adj whilst we
408  * do this, but we do not have that level of granularity - it's suspend all
409  * worker threads or nothing.
410  * The other choices are:
411  * - to mark the adj down and back walk so child load-balances drop this adj
412  * from the set.
413  * - update the next_node index of this adj to point to error-drop
414  * both of which will mean for MAC change we will drop for this adj
415  * which is not acceptable. However, when the adj changes type (from
416  * complete to incomplete and vice-versa) the child DPOs, which have the
417  * VLIB graph next node index, will be sending packets to the wrong graph
418  * node. So from the options above, updating the next_node of the adj to
419  * be drop will work, but it relies on each graph node v4/v6/mpls, rewrite/
420  * arp/midchain always be valid w.r.t. a mis-match of adj type and node type
421  * (i.e. a rewrite adj in the arp node). This is not enforceable. Getting it
422  * wrong will lead to hard to find bugs since its a race condition. So we
423  * choose the more reliable method of updating the children to use the drop,
424  * then switching adj's type, then updating the children again. Did I mention
425  * that this doesn't happen often...
426  * So we need to distinguish between the two cases:
427  * 1 - mac change
428  * 2 - adj type change
429  */
430  if (do_walk &&
431  old_next != adj_next_index &&
432  ADJ_INDEX_INVALID != walk_ai)
433  {
434  /*
435  * the adj is changing type. we need to fix all children so that they
436  * stack momentarily on a drop, while the adj changes. If we don't do
437  * this the children will send packets to a VLIB graph node that does
438  * not correspond to the adj's type - and it goes downhill from there.
439  */
440  fib_node_back_walk_ctx_t bw_ctx = {
442  /*
443  * force this walk to be synchronous. if we don't and a node in the graph
444  * (a heavily shared path-list) chooses to back-ground the walk (make it
445  * async) then it will pause and we will do the adj update below, before
446  * all the children are updated. not good.
447  */
448  .fnbw_flags = FIB_NODE_BW_FLAG_FORCE_SYNC,
449  };
450 
451  fib_walk_sync(FIB_NODE_TYPE_ADJ, walk_ai, &bw_ctx);
452  }
453 
454  /*
455  * If we are just updating the MAC string of the adj (which we also can't
456  * do atomically), then we need to stop packets switching through the adj.
457  * We can't do that on a per-adj basis, so it's all the packets.
458  * If we are updating the type, and we walked back to the children above,
459  * then this barrier serves to flush the queues/frames.
460  */
462 
463  adj->lookup_next_index = adj_next_index;
464 
465  if (NULL != rewrite)
466  {
467  /*
468  * new rewrite provided.
469  * fill in the adj's rewrite string, and build the VLIB graph arc.
470  */
471  vnet_rewrite_set_data_internal(&adj->rewrite_header,
472  sizeof(adj->rewrite_data),
473  rewrite,
474  vec_len(rewrite));
475  vec_free(rewrite);
476  }
477  else
478  {
479  vnet_rewrite_clear_data_internal(&adj->rewrite_header,
480  sizeof(adj->rewrite_data));
481  }
482  adj->rewrite_header.next_index = vlib_node_add_next(vlib_get_main(),
483  this_node,
484  next_node);
485 
486  /*
487  * done with the rewrite update - let the workers loose.
488  */
490 
491  if (do_walk &&
492  (old_next != adj->lookup_next_index) &&
493  (ADJ_INDEX_INVALID != walk_ai))
494  {
495  /*
496  * backwalk to the children so they can stack on the now updated
497  * adjacency
498  */
499  fib_node_back_walk_ctx_t bw_ctx = {
501  };
502 
503  fib_walk_sync(FIB_NODE_TYPE_ADJ, walk_ai, &bw_ctx);
504  }
505  /*
506  * Prevent re-entrant walk of the same adj
507  */
508  if (do_walk)
509  {
510  walk_adj->ia_flags &= ~ADJ_FLAG_SYNC_WALK_ACTIVE;
511  }
512 
514  adj_unlock(walk_ai);
515 }
516 
517 typedef struct adj_db_count_ctx_t_ {
520 
521 static void
522 adj_db_count (BVT(clib_bihash_kv) * kvp,
523  void *arg)
524 {
525  adj_db_count_ctx_t * ctx = arg;
526  ctx->count++;
527 }
528 
529 u32
531 {
533  .count = 0,
534  };
535  fib_protocol_t proto;
536  u32 sw_if_index = 0;
537 
538  for (proto = FIB_PROTOCOL_IP4; proto <= FIB_PROTOCOL_IP6; proto++)
539  {
540  vec_foreach_index(sw_if_index, adj_nbr_tables[proto])
541  {
542  if (NULL != adj_nbr_tables[proto][sw_if_index])
543  {
545  adj_nbr_tables[proto][sw_if_index],
546  adj_db_count,
547  &ctx);
548  }
549  }
550  }
551  return (ctx.count);
552 }
553 
554 /**
555  * @brief Context for a walk of the adjacency neighbour DB
556  */
557 typedef struct adj_walk_ctx_t_
558 {
560  void *awc_ctx;
562 
563 static void
564 adj_nbr_walk_cb (BVT(clib_bihash_kv) * kvp,
565  void *arg)
566 {
567  adj_walk_ctx_t *ctx = arg;
568 
569  // FIXME: can't stop early...
570  ctx->awc_cb(kvp->value, ctx->awc_ctx);
571 }
572 
573 void
575  fib_protocol_t adj_nh_proto,
576  adj_walk_cb_t cb,
577  void *ctx)
578 {
579  if (!ADJ_NBR_ITF_OK(adj_nh_proto, sw_if_index))
580  return;
581 
582  adj_walk_ctx_t awc = {
583  .awc_ctx = ctx,
584  .awc_cb = cb,
585  };
586 
588  adj_nbr_tables[adj_nh_proto][sw_if_index],
590  &awc);
591 }
592 
593 /**
594  * @brief Walk adjacencies on a link with a given v4 next-hop.
595  * that is visit the adjacencies with different link types.
596  */
597 void
599  const ip4_address_t *addr,
600  adj_walk_cb_t cb,
601  void *ctx)
602 {
603  if (!ADJ_NBR_ITF_OK(FIB_PROTOCOL_IP4, sw_if_index))
604  return;
605 
606  ip46_address_t nh = {
607  .ip4 = *addr,
608  };
609  vnet_link_t linkt;
610  adj_index_t ai;
611 
612  FOR_EACH_VNET_LINK(linkt)
613  {
614  ai = adj_nbr_find (FIB_PROTOCOL_IP4, linkt, &nh, sw_if_index);
615 
616  if (INDEX_INVALID != ai)
617  cb(ai, ctx);
618  }
619 }
620 
621 /**
622  * @brief Walk adjacencies on a link with a given v6 next-hop.
623  * that is visit the adjacencies with different link types.
624  */
625 void
627  const ip6_address_t *addr,
628  adj_walk_cb_t cb,
629  void *ctx)
630 {
631  if (!ADJ_NBR_ITF_OK(FIB_PROTOCOL_IP6, sw_if_index))
632  return;
633 
634  ip46_address_t nh = {
635  .ip6 = *addr,
636  };
637  vnet_link_t linkt;
638  adj_index_t ai;
639 
640  FOR_EACH_VNET_LINK(linkt)
641  {
642  ai = adj_nbr_find (FIB_PROTOCOL_IP6, linkt, &nh, sw_if_index);
643 
644  if (INDEX_INVALID != ai)
645  cb(ai, ctx);
646  }
647 }
648 
649 /**
650  * @brief Walk adjacencies on a link with a given next-hop.
651  * that is visit the adjacencies with different link types.
652  */
653 void
655  fib_protocol_t adj_nh_proto,
656  const ip46_address_t *nh,
657  adj_walk_cb_t cb,
658  void *ctx)
659 {
660  if (!ADJ_NBR_ITF_OK(adj_nh_proto, sw_if_index))
661  return;
662 
663  vnet_link_t linkt;
664  adj_index_t ai;
665 
666  FOR_EACH_VNET_LINK(linkt)
667  {
668  ai = adj_nbr_find (FIB_PROTOCOL_IP4, linkt, nh, sw_if_index);
669 
670  if (INDEX_INVALID != ai)
671  cb(ai, ctx);
672  }
673 }
674 
675 /**
676  * Flags associated with the interface state walks
677  */
679 {
682 
683 /**
684  * Context for the state change walk of the DB
685  */
687 {
688  /**
689  * Flags on the interface
690  */
693 
694 static adj_walk_rc_t
696  void *arg)
697 {
698  /*
699  * Back walk the graph to inform the forwarding entries
700  * that this interface state has changed. Do this synchronously
701  * since this is the walk that provides convergence
702  */
704  fib_node_back_walk_ctx_t bw_ctx = {
705  .fnbw_reason = ((ctx->flags & ADJ_NBR_INTERFACE_UP) ?
708  /*
709  * the force sync applies only as far as the first fib_entry.
710  * And it's the fib_entry's we need to converge away from
711  * the adjacencies on the now down link
712  */
713  .fnbw_flags = (!(ctx->flags & ADJ_NBR_INTERFACE_UP) ?
716  };
717  ip_adjacency_t *adj;
718 
719  adj = adj_get(ai);
720 
722  fib_walk_sync(FIB_NODE_TYPE_ADJ, ai, &bw_ctx);
724 
725  return (ADJ_WALK_RC_CONTINUE);
726 }
727 
728 /**
729  * @brief Registered function for SW interface state changes
730  */
731 static clib_error_t *
734  u32 flags)
735 {
736  fib_protocol_t proto;
737 
738  /*
739  * walk each adj on the interface and trigger a walk from that adj
740  */
741  for (proto = FIB_PROTOCOL_IP4; proto <= FIB_PROTOCOL_IP6; proto++)
742  {
744  .flags = ((flags & VNET_SW_INTERFACE_FLAG_ADMIN_UP) ?
746  0),
747  };
748 
749  adj_nbr_walk(sw_if_index, proto,
751  &ctx);
752  }
753 
754  return (NULL);
755 }
756 
760 
761 /**
762  * @brief Invoked on each SW interface of a HW interface when the
763  * HW interface state changes
764  */
765 static walk_rc_t
768  void *arg)
769 {
771  fib_protocol_t proto;
772 
773  /*
774  * walk each adj on the interface and trigger a walk from that adj
775  */
776  for (proto = FIB_PROTOCOL_IP4; proto <= FIB_PROTOCOL_IP6; proto++)
777  {
778  adj_nbr_walk(sw_if_index, proto,
780  ctx);
781  }
782  return (WALK_CONTINUE);
783 }
784 
785 /**
786  * @brief Registered callback for HW interface state changes
787  */
788 static clib_error_t *
790  u32 hw_if_index,
791  u32 flags)
792 {
793  /*
794  * walk SW interface on the HW
795  */
797  .flags = ((flags & VNET_HW_INTERFACE_FLAG_LINK_UP) ?
799  0),
800  };
801 
802  vnet_hw_interface_walk_sw(vnm, hw_if_index,
804  &ctx);
805 
806  return (NULL);
807 }
808 
812 
813 static adj_walk_rc_t
815  void *arg)
816 {
817  /*
818  * Back walk the graph to inform the forwarding entries
819  * that this interface has been deleted.
820  */
821  fib_node_back_walk_ctx_t bw_ctx = {
823  };
824  ip_adjacency_t *adj;
825 
826  adj = adj_get(ai);
827 
829  fib_walk_sync(FIB_NODE_TYPE_ADJ, ai, &bw_ctx);
831 
832  return (ADJ_WALK_RC_CONTINUE);
833 }
834 
835 /**
836  * adj_nbr_interface_add_del
837  *
838  * Registered to receive interface Add and delete notifications
839  */
840 static clib_error_t *
843  u32 is_add)
844 {
845  fib_protocol_t proto;
846 
847  if (is_add)
848  {
849  /*
850  * not interested in interface additions. we will not back walk
851  * to resolve paths through newly added interfaces. Why? The control
852  * plane should have the brains to add interfaces first, then routes.
853  * So the case where there are paths with a interface that matches
854  * one just created is the case where the path resolved through an
855  * interface that was deleted, and still has not been removed. The
856  * new interface added, is NO GUARANTEE that the interface being
857  * added now, even though it may have the same sw_if_index, is the
858  * same interface that the path needs. So tough!
859  * If the control plane wants these routes to resolve it needs to
860  * remove and add them again.
861  */
862  return (NULL);
863  }
864 
865  for (proto = FIB_PROTOCOL_IP4; proto <= FIB_PROTOCOL_IP6; proto++)
866  {
867  adj_nbr_walk(sw_if_index, proto,
869  NULL);
870  }
871 
872  return (NULL);
873 
874 }
875 
877 
878 
879 static adj_walk_rc_t
881  void *arg)
882 {
883  vlib_cli_output (arg, "[@%d] %U",
884  ai,
887 
888  return (ADJ_WALK_RC_CONTINUE);
889 }
890 
891 static clib_error_t *
893  unformat_input_t * input,
894  vlib_cli_command_t * cmd)
895 {
897  u32 sw_if_index = ~0;
898 
900  {
901  if (unformat (input, "%d", &ai))
902  ;
903  else if (unformat (input, "%U",
905  &sw_if_index))
906  ;
907  else
908  break;
909  }
910 
911  if (ADJ_INDEX_INVALID != ai)
912  {
913  vlib_cli_output (vm, "[@%d] %U",
914  ai,
917  }
918  else if (~0 != sw_if_index)
919  {
920  fib_protocol_t proto;
921 
922  for (proto = FIB_PROTOCOL_IP4; proto <= FIB_PROTOCOL_IP6; proto++)
923  {
924  adj_nbr_walk(sw_if_index, proto,
926  vm);
927  }
928  }
929  else
930  {
931  fib_protocol_t proto;
932 
933  for (proto = FIB_PROTOCOL_IP4; proto <= FIB_PROTOCOL_IP6; proto++)
934  {
935  vec_foreach_index(sw_if_index, adj_nbr_tables[proto])
936  {
937  adj_nbr_walk(sw_if_index, proto,
939  vm);
940  }
941  }
942  }
943 
944  return 0;
945 }
946 
947 /*?
948  * Show all neighbour adjacencies.
949  * @cliexpar
950  * @cliexstart{sh adj nbr}
951  * [@2] ipv4 via 1.0.0.2 loop0: IP4: 00:00:22:aa:bb:cc -> 00:00:11:aa:bb:cc
952  * [@3] mpls via 1.0.0.2 loop0: MPLS_UNICAST: 00:00:22:aa:bb:cc -> 00:00:11:aa:bb:cc
953  * [@4] ipv4 via 1.0.0.3 loop0: IP4: 00:00:22:aa:bb:cc -> 00:00:11:aa:bb:cc
954  * [@5] mpls via 1.0.0.3 loop0: MPLS_UNICAST: 00:00:22:aa:bb:cc -> 00:00:11:aa:bb:cc
955  * @cliexend
956  ?*/
957 VLIB_CLI_COMMAND (ip4_show_fib_command, static) = {
958  .path = "show adj nbr",
959  .short_help = "show adj nbr [<adj_index>] [interface]",
960  .function = adj_nbr_show,
961 };
962 
963 u8*
964 format_adj_nbr_incomplete (u8* s, va_list *ap)
965 {
966  index_t index = va_arg(*ap, index_t);
967  CLIB_UNUSED(u32 indent) = va_arg(*ap, u32);
968  vnet_main_t * vnm = vnet_get_main();
969  ip_adjacency_t * adj = adj_get(index);
970 
971  s = format (s, "arp-%U", format_vnet_link, adj->ia_link);
972  s = format (s, ": via %U",
973  format_ip46_address, &adj->sub_type.nbr.next_hop,
975  s = format (s, " %U",
977  vnm, adj->rewrite_header.sw_if_index);
978 
979  return (s);
980 }
981 
982 u8*
983 format_adj_nbr (u8* s, va_list *ap)
984 {
985  index_t index = va_arg(*ap, index_t);
986  CLIB_UNUSED(u32 indent) = va_arg(*ap, u32);
987  ip_adjacency_t * adj = adj_get(index);
988 
989  s = format (s, "%U", format_vnet_link, adj->ia_link);
990  s = format (s, " via %U ",
991  format_ip46_address, &adj->sub_type.nbr.next_hop,
993  s = format (s, "%U",
995  &adj->rewrite_header, sizeof (adj->rewrite_data), 0);
996 
997  return (s);
998 }
999 
1000 static void
1002 {
1003  adj_lock(dpo->dpoi_index);
1004 }
1005 static void
1007 {
1008  adj_unlock(dpo->dpoi_index);
1009 }
1010 
1011 static void
1013 {
1014  fib_show_memory_usage("Adjacency",
1016  pool_len(adj_pool),
1017  sizeof(ip_adjacency_t));
1018 }
1019 
1020 const static dpo_vft_t adj_nbr_dpo_vft = {
1021  .dv_lock = adj_dpo_lock,
1022  .dv_unlock = adj_dpo_unlock,
1023  .dv_format = format_adj_nbr,
1024  .dv_mem_show = adj_mem_show,
1025  .dv_get_urpf = adj_dpo_get_urpf,
1026 };
1027 const static dpo_vft_t adj_nbr_incompl_dpo_vft = {
1028  .dv_lock = adj_dpo_lock,
1029  .dv_unlock = adj_dpo_unlock,
1030  .dv_format = format_adj_nbr_incomplete,
1031  .dv_get_urpf = adj_dpo_get_urpf,
1032 };
1033 
1034 /**
1035  * @brief The per-protocol VLIB graph nodes that are assigned to an adjacency
1036  * object.
1037  *
1038  * this means that these graph nodes are ones from which a nbr is the
1039  * parent object in the DPO-graph.
1040  */
1041 const static char* const nbr_ip4_nodes[] =
1042 {
1043  "ip4-rewrite",
1044  NULL,
1045 };
1046 const static char* const nbr_ip6_nodes[] =
1047 {
1048  "ip6-rewrite",
1049  NULL,
1050 };
1051 const static char* const nbr_mpls_nodes[] =
1052 {
1053  "mpls-output",
1054  NULL,
1055 };
1056 const static char* const nbr_ethernet_nodes[] =
1057 {
1058  "adj-l2-rewrite",
1059  NULL,
1060 };
1061 const static char* const * const nbr_nodes[DPO_PROTO_NUM] =
1062 {
1067 };
1068 
1069 const static char* const nbr_incomplete_ip4_nodes[] =
1070 {
1071  "ip4-arp",
1072  NULL,
1073 };
1074 const static char* const nbr_incomplete_ip6_nodes[] =
1075 {
1076  "ip6-discover-neighbor",
1077  NULL,
1078 };
1079 const static char* const nbr_incomplete_mpls_nodes[] =
1080 {
1081  "mpls-adj-incomplete",
1082  NULL,
1083 };
1084 
1085 const static char* const * const nbr_incomplete_nodes[DPO_PROTO_NUM] =
1086 {
1090 };
1091 
1092 void
1094 {
1096  &adj_nbr_dpo_vft,
1097  nbr_nodes);
1099  &adj_nbr_incompl_dpo_vft,
1100  nbr_incomplete_nodes);
1101 }
#define vec_validate(V, I)
Make sure vector is long enough for given index (no header, unspecified alignment) ...
Definition: vec.h:439
u32 sw_if_index
Definition: ipsec_gre.api:37
dpo_lock_fn_t dv_lock
A reference counting lock function.
Definition: dpo.h:404
void adj_nbr_walk_nh(u32 sw_if_index, fib_protocol_t adj_nh_proto, const ip46_address_t *nh, adj_walk_cb_t cb, void *ctx)
Walk adjacencies on a link with a given next-hop.
Definition: adj_nbr.c:654
static clib_error_t * adj_nbr_hw_interface_state_change(vnet_main_t *vnm, u32 hw_if_index, u32 flags)
Registered callback for HW interface state changes.
Definition: adj_nbr.c:789
#define vec_foreach_index(var, v)
Iterate over vector indices.
adj_flags_t ia_flags
Flags on the adjacency 1-bytes.
Definition: adj.h:255
u32 flags
Definition: vhost_user.h:115
Context for a walk of the adjacency neighbour DB.
Definition: adj_nbr.c:557
ip_adjacency_t * adj_pool
The global adjacnecy pool.
Definition: adj.c:33
#define CLIB_UNUSED(x)
Definition: clib.h:82
A virtual function table regisitered for a DPO type.
Definition: dpo.h:399
enum adj_nbr_interface_flags_t_ adj_nbr_interface_flags_t
Flags associated with the interface state walks.
u8 * format_adj_nbr(u8 *s, va_list *ap)
Format a neigbour (REWRITE) adjacency.
Definition: adj_nbr.c:983
void adj_lock(adj_index_t adj_index)
Take a reference counting lock on the adjacency.
Definition: adj.c:301
An indication that the rewrite is complete, i.e.
Definition: adj_nbr.h:98
vnet_main_t * vnet_get_main(void)
Definition: misc.c:47
static const char *const nbr_ethernet_nodes[]
Definition: adj_nbr.c:1056
static const char *const nbr_incomplete_ip6_nodes[]
Definition: adj_nbr.c:1074
unsigned long u64
Definition: types.h:89
static adj_walk_rc_t adj_nbr_interface_state_change_one(adj_index_t ai, void *arg)
Definition: adj_nbr.c:695
void vnet_hw_interface_walk_sw(vnet_main_t *vnm, u32 hw_if_index, vnet_hw_sw_interface_walk_t fn, void *ctx)
Walk the SW interfaces on a HW interface - this is the super interface and any sub-interfaces.
Definition: interface.c:1021
#define NULL
Definition: clib.h:58
Broadcasr Adjacency.
Definition: adj.h:85
IP unicast adjacency.
Definition: adj.h:221
Context for the state change walk of the DB.
Definition: adj_nbr.c:686
This packet is to be rewritten and forwarded to the next processing node.
Definition: adj.h:73
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
format_function_t format_ip46_address
Definition: format.h:61
clib_memset(h->entries, 0, sizeof(h->entries[0])*entries)
ip_lookup_main_t lookup_main
Definition: ip4.h:98
adj_walk_cb_t awc_cb
Definition: adj_nbr.c:559
void adj_nbr_walk_nh4(u32 sw_if_index, const ip4_address_t *addr, adj_walk_cb_t cb, void *ctx)
Walk adjacencies on a link with a given v4 next-hop.
Definition: adj_nbr.c:598
u8 * format(u8 *s, const char *fmt,...)
Definition: format.c:424
unformat_function_t unformat_vnet_sw_interface
u8 * format_adj_nbr_incomplete(u8 *s, va_list *ap)
Format aa incomplete neigbour (ARP) adjacency.
Definition: adj_nbr.c:964
static const char *const nbr_incomplete_mpls_nodes[]
Definition: adj_nbr.c:1079
u32 adj_dpo_get_urpf(const dpo_id_t *dpo)
Definition: adj.c:291
vhost_vring_addr_t addr
Definition: vhost_user.h:121
adj_index_t adj_nbr_add_or_lock_w_rewrite(fib_protocol_t nh_proto, vnet_link_t link_type, const ip46_address_t *nh_addr, u32 sw_if_index, u8 *rewrite)
Add (and lock) a new or lock an existing neighbour adjacency.
Definition: adj_nbr.c:263
format_function_t format_vnet_sw_if_index_name
static uword vlib_node_add_next(vlib_main_t *vm, uword node, uword next_node)
Definition: node_funcs.h:1122
unsigned char u8
Definition: types.h:56
ip_lookup_next_t
An adjacency is a representation of an attached L3 peer.
Definition: adj.h:50
struct ip_adjacency_t_::@46::@47 nbr
IP_LOOKUP_NEXT_ARP/IP_LOOKUP_NEXT_REWRITE.
#define pool_len(p)
Number of elements in pool vector.
Definition: pool.h:140
enum fib_protocol_t_ fib_protocol_t
Protocol Type.
#define vlib_worker_thread_barrier_sync(X)
Definition: threads.h:204
vnet_link_t ia_link
link/ether-type 1 bytes
Definition: adj.h:242
#define fm
enum walk_rc_t_ walk_rc_t
Walk return code.
u8 output_feature_arc_index
Definition: lookup.h:140
static clib_error_t * adj_nbr_sw_interface_state_change(vnet_main_t *vnm, u32 sw_if_index, u32 flags)
Registered function for SW interface state changes.
Definition: adj_nbr.c:732
static ip_adjacency_t * adj_get(adj_index_t adj_index)
Get a pointer to an adjacency object from its index.
Definition: adj.h:433
vlib_node_registration_t ip6_discover_neighbor_node
(constructor) VLIB_REGISTER_NODE (ip6_discover_neighbor_node)
VNET_SW_INTERFACE_ADMIN_UP_DOWN_FUNCTION_PRIO(adj_nbr_sw_interface_state_change, VNET_ITF_FUNC_PRIORITY_HIGH)
void dpo_register(dpo_type_t type, const dpo_vft_t *vft, const char *const *const *nodes)
For a given DPO type Register:
Definition: dpo.c:321
int clib_bihash_add_del(clib_bihash *h, clib_bihash_kv *add_v, int is_add)
Add or delete a (key,value) pair from a bi-hash table.
format_function_t format_ip_adjacency
Definition: format.h:58
void fib_walk_sync(fib_node_type_t parent_type, fib_node_index_t parent_index, fib_node_back_walk_ctx_t *ctx)
Back walk all the children of a FIB node.
Definition: fib_walk.c:745
static void vnet_rewrite_clear_data_internal(vnet_rewrite_header_t *rw, int max_size)
Definition: rewrite.h:116
static const char *const nbr_incomplete_ip4_nodes[]
Definition: adj_nbr.c:1069
static BVT(clib_bihash)
Definition: adj_nbr.c:28
enum adj_walk_rc_t_ adj_walk_rc_t
return codes from a adjacency walker callback function
static walk_rc_t adj_nbr_hw_sw_interface_state_change(vnet_main_t *vnm, u32 sw_if_index, void *arg)
Invoked on each SW interface of a HW interface when the HW interface state changes.
Definition: adj_nbr.c:766
static clib_error_t * adj_nbr_show(vlib_main_t *vm, unformat_input_t *input, vlib_cli_command_t *cmd)
Definition: adj_nbr.c:892
struct adj_walk_ctx_t_ adj_walk_ctx_t
Context for a walk of the adjacency neighbour DB.
static const char *const nbr_mpls_nodes[]
Definition: adj_nbr.c:1051
static void adj_nbr_walk_cb(BVT(clib_bihash_kv)*kvp, void *arg)
Definition: adj_nbr.c:564
static void adj_dpo_lock(dpo_id_t *dpo)
Definition: adj_nbr.c:1001
void fib_show_memory_usage(const char *name, u32 in_use_elts, u32 allocd_elts, size_t size_elt)
Show the memory usage for a type.
Definition: fib_node.c:220
void adj_unlock(adj_index_t adj_index)
Release a reference counting lock on the adjacency.
Definition: adj.c:318
void vnet_update_adjacency_for_sw_interface(vnet_main_t *vnm, u32 sw_if_index, u32 ai)
Definition: rewrite.c:205
unsigned int u32
Definition: types.h:88
static const char *const nbr_ip6_nodes[]
Definition: adj_nbr.c:1046
static void adj_nbr_evaluate_feature(adj_index_t ai)
Check and set feature flags if o/p interface has any o/p features.
Definition: adj_nbr.c:141
format_function_t format_vnet_rewrite
Definition: rewrite.h:253
u8 output_feature_arc_index
Definition: mpls.h:57
u32 adj_nbr_db_size(void)
Return the size of the adjacency database.
Definition: adj_nbr.c:530
#define ADJ_NBR_DEFAULT_HASH_NUM_BUCKETS
vlib_node_registration_t ip4_arp_node
(constructor) VLIB_REGISTER_NODE (ip4_arp_node)
Definition: ip4_forward.c:1939
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
fib_node_bw_reason_flag_t fnbw_reason
The reason/trigger for the backwalk.
Definition: fib_node.h:208
#define ADJ_INDEX_INVALID
Invalid ADJ index - used when no adj is known likewise blazoned capitals INVALID speak volumes where ...
Definition: adj_types.h:36
void adj_nbr_remove(adj_index_t ai, fib_protocol_t nh_proto, vnet_link_t link_type, const ip46_address_t *nh_addr, u32 sw_if_index)
Definition: adj_nbr.c:81
long ctx[MAX_CONNS]
Definition: main.c:144
struct _unformat_input_t unformat_input_t
static adj_index_t adj_get_index(ip_adjacency_t *adj)
Get a pointer to an adjacency object from its index.
Definition: adj_internal.h:101
static clib_error_t * adj_nbr_interface_add_del(vnet_main_t *vnm, u32 sw_if_index, u32 is_add)
adj_nbr_interface_add_del
Definition: adj_nbr.c:841
#define ADJ_NBR_DEFAULT_HASH_MEMORY_SIZE
void adj_nbr_module_init(void)
Module initialisation.
Definition: adj_nbr.c:1093
void clib_bihash_init(clib_bihash *h, char *name, u32 nbuckets, uword memory_size)
initialize a bounded index extensible hash table
#define ADJ_NBR_SET_KEY(_key, _lt, _nh)
void clib_bihash_foreach_key_value_pair(clib_bihash *h, void *callback, void *arg)
Visit active (key,value) pairs in a bi-hash table.
This packet matches an "incomplete adjacency" and packets need to be passed to ARP to find rewrite st...
Definition: adj.h:63
#define UNFORMAT_END_OF_INPUT
Definition: format.h:144
void vnet_rewrite_init(vnet_main_t *vnm, u32 sw_if_index, vnet_link_t linkt, u32 this_node, u32 next_node, vnet_rewrite_header_t *rw)
Definition: rewrite.c:80
mpls_main_t mpls_main
Definition: mpls.c:25
vlib_main_t * vm
Definition: buffer.c:312
#define vec_free(V)
Free vector&#39;s memory (no header).
Definition: vec.h:341
static adj_walk_rc_t adj_nbr_show_one(adj_index_t ai, void *arg)
Definition: adj_nbr.c:880
Force the walk to be synchronous.
Definition: fib_node.h:170
u32 vnet_tx_node_index_for_sw_interface(vnet_main_t *vnm, u32 sw_if_index)
Definition: rewrite.c:73
static void vnet_rewrite_set_data_internal(vnet_rewrite_header_t *rw, int max_size, void *data, int data_bytes)
Definition: rewrite.h:126
adj_walk_rc_t(* adj_walk_cb_t)(adj_index_t ai, void *ctx)
Call back function when walking adjacencies.
Definition: adj_types.h:50
u32 adj_index_t
An index for adjacencies.
Definition: adj_types.h:30
static void adj_mem_show(void)
Definition: adj_nbr.c:1012
static ip_adjacency_t * adj_nbr_alloc(fib_protocol_t nh_proto, vnet_link_t link_type, const ip46_address_t *nh_addr, u32 sw_if_index)
Definition: adj_nbr.c:178
void adj_nbr_walk(u32 sw_if_index, fib_protocol_t adj_nh_proto, adj_walk_cb_t cb, void *ctx)
Walk the neighbour Adjacencies on a given interface.
Definition: adj_nbr.c:574
i16 ** feature_count_by_sw_if_index
feature reference counts by interface
Definition: feature.h:109
#define FOR_EACH_VNET_LINK(_link)
Definition: interface.h:333
Context passed between object during a back walk.
Definition: fib_node.h:204
#define VLIB_CLI_COMMAND(x,...)
Definition: cli.h:155
VNET_HW_INTERFACE_LINK_UP_DOWN_FUNCTION_PRIO(adj_nbr_hw_interface_state_change, VNET_ITF_FUNC_PRIORITY_HIGH)
adj_nbr_interface_flags_t flags
Flags on the interface.
Definition: adj_nbr.c:691
#define ASSERT(truth)
ip6_main_t ip6_main
Definition: ip6_forward.c:2688
ip_lookup_main_t lookup_main
Definition: ip6.h:179
u8 is_add
Definition: ipsec_gre.api:36
enum vnet_link_t_ vnet_link_t
Link Type: A description of the protocol of packets on the link.
void * awc_ctx
Definition: adj_nbr.c:560
static const char *const nbr_ip4_nodes[]
The per-protocol VLIB graph nodes that are assigned to an adjacency object.
Definition: adj_nbr.c:1041
static u32 adj_get_rewrite_node(vnet_link_t linkt)
Definition: adj_internal.h:46
static u32 adj_get_nd_node(fib_protocol_t proto)
Definition: adj_nbr.c:123
static vlib_main_t * vlib_get_main(void)
Definition: global_funcs.h:23
fib_protocol_t ia_nh_proto
The protocol of the neighbor/peer.
Definition: adj.h:249
#define DPO_PROTO_NUM
Definition: dpo.h:70
index_t dpoi_index
the index of objects of that type
Definition: dpo.h:184
union ip_adjacency_t_::@46 sub_type
#define ip46_address_is_equal(a1, a2)
Definition: ip6_packet.h:94
#define vec_len(v)
Number of elements in vector (rvalue-only, NULL tolerant)
ip_lookup_next_t lookup_next_index
Next hop after ip4-lookup.
Definition: adj.h:236
void adj_nbr_update_rewrite_internal(ip_adjacency_t *adj, ip_lookup_next_t adj_next_index, u32 this_node, u32 next_node, u8 *rewrite)
adj_nbr_update_rewrite_internal
Definition: adj_nbr.c:340
enum adj_nbr_rewrite_flag_t_ adj_nbr_rewrite_flag_t
When adding a rewrite to an adjacency these are flags that apply to that rewrite. ...
#define INDEX_INVALID
Invalid index - used when no index is known blazoned capitals INVALID speak volumes where ~0 does not...
Definition: dpo.h:47
ip_adjacency_t * adj_alloc(fib_protocol_t proto)
Definition: adj.c:63
static void adj_db_count(BVT(clib_bihash_kv)*kvp, void *arg)
Definition: adj_nbr.c:522
static adj_walk_rc_t adj_nbr_interface_delete_one(adj_index_t ai, void *arg)
Definition: adj_nbr.c:814
#define FIB_PROTOCOL_MAX
Definition outside of enum so it does not need to be included in non-defaulted switch statements...
Definition: fib_types.h:52
static void * clib_mem_alloc_aligned(uword size, uword align)
Definition: mem.h:140
adj_nbr_interface_flags_t_
Flags associated with the interface state walks.
Definition: adj_nbr.c:678
void vlib_worker_thread_barrier_release(vlib_main_t *vm)
Definition: threads.c:1487
ip4_main_t ip4_main
Global ip4 main structure.
Definition: ip4_forward.c:905
adj_index_t adj_nbr_add_or_lock(fib_protocol_t nh_proto, vnet_link_t link_type, const ip46_address_t *nh_addr, u32 sw_if_index)
Neighbour Adjacency sub-type.
Definition: adj_nbr.c:218
struct adj_db_count_ctx_t_ adj_db_count_ctx_t
vnet_link_t fib_proto_to_link(fib_protocol_t proto)
Convert from a protocol to a link type.
Definition: fib_types.c:271
u8 * format_vnet_link(u8 *s, va_list *ap)
Definition: fib_types.c:40
VNET_SW_INTERFACE_ADD_DEL_FUNCTION(adj_nbr_interface_add_del)
static void adj_dpo_unlock(dpo_id_t *dpo)
Definition: adj_nbr.c:1006
#define CLIB_CACHE_LINE_BYTES
Definition: cache.h:59
#define ADJ_NBR_ITF_OK(_proto, _itf)
This adjacency/interface has output features configured.
Definition: rewrite.h:57
void vnet_rewrite_update_mtu(vnet_main_t *vnm, vnet_link_t linkt, vnet_rewrite_header_t *rw)
Definition: rewrite.c:92
vnet_feature_main_t feature_main
Definition: feature.c:19
void adj_nbr_update_rewrite(adj_index_t adj_index, adj_nbr_rewrite_flag_t flags, u8 *rewrite)
adj_nbr_update_rewrite
Definition: adj_nbr.c:298
void vlib_cli_output(vlib_main_t *vm, char *fmt,...)
Definition: cli.c:762
const ip46_address_t ADJ_BCAST_ADDR
The special broadcast address (to construct a broadcast adjacency.
Definition: adj.c:41
struct adj_nbr_interface_state_change_ctx_t_ adj_nbr_interface_state_change_ctx_t
Context for the state change walk of the DB.
uword unformat(unformat_input_t *i, const char *fmt,...)
Definition: unformat.c:972
static uword unformat_check_input(unformat_input_t *i)
Definition: format.h:170
static ip46_type_t adj_proto_to_46(fib_protocol_t proto)
Definition: adj_internal.h:82
signed short i16
Definition: types.h:46
adj_index_t adj_nbr_find(fib_protocol_t nh_proto, vnet_link_t link_type, const ip46_address_t *nh_addr, u32 sw_if_index)
Lookup neighbor adjancency.
Definition: adj_nbr.c:99
void adj_nbr_walk_nh6(u32 sw_if_index, const ip6_address_t *addr, adj_walk_cb_t cb, void *ctx)
Walk adjacencies on a link with a given v6 next-hop.
Definition: adj_nbr.c:626
static uword pool_elts(void *v)
Number of active elements in a pool.
Definition: pool.h:128