BGP: route-map scale

- use a hash to store the route-maps
- reduce the number of route_map_lookup_by_name() calls in BGP

Signed-off-by: Daniel Walton <dwalton@cumulusnetworks.com>
Reviewed-by:   Donald Sharp <sharpd@cumulusnetworks.com>

Ticket: CM-7407

bgpd/bgp_routemap.c

@@ -2666,8 +2666,9 @@ bgp_route_set_delete (struct vty *vty, struct route_map_index *index,
  * modifications.
  */
 static void
-bgp_route_map_process_peer (const char *rmap_name, struct peer *peer,
+bgp_route_map_process_peer (const char *rmap_name, struct route_map *map,
-			    int afi, int safi, int route_update)
+                            struct peer *peer, int afi, int safi,
+                            int route_update)
 {
 
   int update;
@@ -2687,8 +2688,7 @@ bgp_route_map_process_peer (const char *rmap_name, struct peer *peer,
       if (filter->map[RMAP_IN].name &&
 	  (strcmp(rmap_name, filter->map[RMAP_IN].name) == 0))
 	{
-	  filter->map[RMAP_IN].map =
+	  filter->map[RMAP_IN].map = map;
-	    route_map_lookup_by_name (filter->map[RMAP_IN].name);
 
 	  if (route_update && peer->status == Established)
 	    {
@@ -2723,17 +2723,14 @@ bgp_route_map_process_peer (const char *rmap_name, struct peer *peer,
       if (filter->map[RMAP_IMPORT].name &&
 	  (strcmp(rmap_name, filter->map[RMAP_IMPORT].name) == 0))
 	{
-	  filter->map[RMAP_IMPORT].map =
+	  filter->map[RMAP_IMPORT].map = map;
-	    route_map_lookup_by_name (filter->map[RMAP_IMPORT].name);
 	  update = 1;
 	}
 
       if (filter->map[RMAP_EXPORT].name &&
 	  (strcmp(rmap_name, filter->map[RMAP_EXPORT].name) == 0))
 	{
-	  filter->map[RMAP_EXPORT].map =
+	  filter->map[RMAP_EXPORT].map = map;
-	    route_map_lookup_by_name (filter->map[RMAP_EXPORT].name);
-
 	  update = 1;
 	}
 
@@ -2769,21 +2766,20 @@ bgp_route_map_process_peer (const char *rmap_name, struct peer *peer,
    */
   if (filter->map[RMAP_OUT].name &&
       (strcmp(rmap_name, filter->map[RMAP_OUT].name) == 0))
-    filter->map[RMAP_OUT].map =
+    filter->map[RMAP_OUT].map = map;
-      route_map_lookup_by_name (filter->map[RMAP_OUT].name);
 
   if (filter->usmap.name &&
       (strcmp(rmap_name, filter->usmap.name) == 0))
-    filter->usmap.map = route_map_lookup_by_name (filter->usmap.name);
+    filter->usmap.map = map;
 
   if (peer->default_rmap[afi][safi].name &&
       (strcmp (rmap_name, peer->default_rmap[afi][safi].name) == 0))
-    peer->default_rmap[afi][safi].map =
+    peer->default_rmap[afi][safi].map = map;
-      route_map_lookup_by_name (peer->default_rmap[afi][safi].name);
 }
 
 static void
-bgp_route_map_update_peer_group(const char *rmap_name, struct bgp *bgp)
+bgp_route_map_update_peer_group(const char *rmap_name, struct route_map *map,
+                                struct bgp *bgp)
 {
   struct peer_group *group;
   struct listnode *node, *nnode;
@@ -2807,16 +2803,22 @@ bgp_route_map_update_peer_group(const char *rmap_name, struct bgp *bgp)
 	    {
 	      if ((filter->map[direct].name) &&
 		  (strcmp(rmap_name, filter->map[direct].name) == 0))
-		filter->map[direct].map =
+		filter->map[direct].map = map;
-		  route_map_lookup_by_name (filter->map[direct].name);
 	    }
 
 	  if (filter->usmap.name &&
 	      (strcmp(rmap_name, filter->usmap.name) == 0))
-	    filter->usmap.map = route_map_lookup_by_name (filter->usmap.name);
+	    filter->usmap.map = map;
 	}
 }
 
+/*
+ * Note that if an extreme number (tens of thousands) of route-maps are in use
+ * and if bgp has an extreme number of peers, network statements, etc then this
+ * function can consume a lot of cycles. This is due to this function being
+ * called for each route-map and within this function we walk the list of peers,
+ * network statements, etc looking to see if they use this route-map.
+ */
 static int
 bgp_route_map_process_update (void *arg, const char *rmap_name, int route_update)
 {
@@ -2828,11 +2830,14 @@ bgp_route_map_process_update (void *arg, const char *rmap_name, int route_update
   struct bgp_static *bgp_static;
   struct bgp *bgp = (struct bgp *)arg;
   struct listnode *node, *nnode;
+  struct route_map *map;
   char buf[INET6_ADDRSTRLEN];
 
   if (!bgp)
     return (-1);
 
+  map = route_map_lookup_by_name (rmap_name);
+
   for (ALL_LIST_ELEMENTS (bgp->peer, node, nnode, peer))
     {
 
@@ -2848,7 +2853,7 @@ bgp_route_map_process_update (void *arg, const char *rmap_name, int route_update
 	      continue;
 
 	    /* process in/out/import/export/default-orig route-maps */
-	    bgp_route_map_process_peer(rmap_name, peer, afi, safi, route_update);
+	    bgp_route_map_process_peer(rmap_name, map, peer, afi, safi, route_update);
 	  }
     }
 
@@ -2857,37 +2862,33 @@ bgp_route_map_process_update (void *arg, const char *rmap_name, int route_update
 			     route_update, 0);
 
   /* update peer-group config (template) */
-  bgp_route_map_update_peer_group(rmap_name, bgp);
+  bgp_route_map_update_peer_group(rmap_name, map, bgp);
 
-  /* For table route-map updates. */
   for (afi = AFI_IP; afi < AFI_MAX; afi++)
     for (safi = SAFI_UNICAST; safi < SAFI_MAX; safi++)
       {
+        /* For table route-map updates. */
 	if (bgp->table_map[afi][safi].name &&
 	    (strcmp(rmap_name, bgp->table_map[afi][safi].name) == 0))
 	  {
-	    bgp->table_map[afi][safi].map =
+	    bgp->table_map[afi][safi].map = map;
-	      route_map_lookup_by_name (bgp->table_map[afi][safi].name);
+
             if (BGP_DEBUG (zebra, ZEBRA))
 	      zlog_debug("Processing route_map %s update on "
 			 "table map", rmap_name);
 	    if (route_update)
 	      bgp_zebra_announce_table(bgp, afi, safi);
 	  }
-      }
 
         /* For network route-map updates. */
-  for (afi = AFI_IP; afi < AFI_MAX; afi++)
+        for (bn = bgp_table_top (bgp->route[afi][safi]); bn; bn = bgp_route_next (bn))
-    for (safi = SAFI_UNICAST; safi < SAFI_MAX; safi++)
-      for (bn = bgp_table_top (bgp->route[afi][safi]); bn;
-	   bn = bgp_route_next (bn))
           if ((bgp_static = bn->info) != NULL)
             {
               if (bgp_static->rmap.name &&
                   (strcmp(rmap_name, bgp_static->rmap.name) == 0))
                 {
-		bgp_static->rmap.map =
+                  bgp_static->rmap.map = map;
-		  route_map_lookup_by_name (bgp_static->rmap.name);
+
                   if (route_update)
                     if (!bgp_static->backdoor)
                       {
@@ -2900,6 +2901,7 @@ bgp_route_map_process_update (void *arg, const char *rmap_name, int route_update
                       }
                 }
             }
+      }
 
   /* For redistribute route-map updates. */
   for (afi = AFI_IP; afi < AFI_MAX; afi++)
@@ -2918,8 +2920,7 @@ bgp_route_map_process_update (void *arg, const char *rmap_name, int route_update
             if (red->rmap.name &&
                 (strcmp(rmap_name, red->rmap.name) == 0))
               {
-                red->rmap.map =
+                red->rmap.map = map;
-                  route_map_lookup_by_name (red->rmap.name);
 
                 if (route_update)
                   {

lib/routemap.c

@@ -66,6 +66,38 @@ struct route_map_list
 
 /* Master list of route map. */
 static struct route_map_list route_map_master = { NULL, NULL, NULL, NULL, NULL };
+struct hash *route_map_master_hash = NULL;
+
+static unsigned int
+route_map_hash_key_make (void *p)
+{
+  const struct route_map *map = p;
+  return string_hash_make (map->name);
+}
+
+static int
+route_map_hash_cmp(const void *p1, const void *p2)
+{
+  const struct route_map *map1 = p1;
+  const struct route_map *map2 = p2;
+
+  if (map1->deleted == map2->deleted)
+    {
+      if (map1->name && map2->name)
+        {
+          if (!strcmp (map1->name, map2->name))
+            {
+              return 1;
+            }
+        }
+      else if (!map1->name && !map2->name)
+        {
+          return 1;
+        }
+    }
+
+  return 0;
+}
 
 enum route_map_upd8_type
   {
@@ -128,6 +160,9 @@ route_map_add (const char *name)
   map = route_map_new (name);
   list = &route_map_master;
 
+  /* Add map to the hash */
+  hash_get(route_map_master_hash, map, hash_alloc_intern);
+
   map->next = NULL;
   map->prev = list->tail;
   if (list->tail)
@@ -172,6 +207,7 @@ route_map_free_map (struct route_map *map)
       else
 	list->head = map->next;
 
+      hash_release(route_map_master_hash, map);
       XFREE (MTYPE_ROUTE_MAP_NAME, map->name);
       XFREE (MTYPE_ROUTE_MAP, map);
     }
@@ -211,14 +247,17 @@ struct route_map *
 route_map_lookup_by_name (const char *name)
 {
   struct route_map *map;
+  struct route_map tmp_map;
 
   if (!name)
     return NULL;
 
-  for (map = route_map_master.head; map; map = map->next)
+  // map.deleted is 0 via memset
-    if ((strcmp (map->name, name) == 0) && (!map->deleted))
+  memset(&tmp_map, 0, sizeof(struct route_map));
+  tmp_map.name = XSTRDUP(MTYPE_ROUTE_MAP_NAME, name);
+  map = hash_lookup(route_map_master_hash, &tmp_map);
+  XFREE(MTYPE_ROUTE_MAP_NAME, tmp_map.name);
   return map;
-  return NULL;
 }
 
 int
@@ -226,13 +265,26 @@ route_map_mark_updated (const char *name, int del_later)
 {
   struct route_map *map;
   int ret = -1;
+  struct route_map tmp_map;
 
-  /* We need to do this walk manually instead of calling lookup_by_name()
+  if (!name)
-   * because the lookup function doesn't return route maps marked as
+    return (ret);
-   * deleted.
+
+  map = route_map_lookup_by_name(name);
+
+  /* If we did not find the routemap with deleted=0 try again
+   * with deleted=1
    */
-  for (map = route_map_master.head; map; map = map->next)
+  if (!map)
-    if (strcmp (map->name, name) == 0)
+    {
+      memset(&tmp_map, 0, sizeof(struct route_map));
+      tmp_map.name = XSTRDUP(MTYPE_ROUTE_MAP_NAME, name);
+      tmp_map.deleted = 1;
+      map = hash_lookup(route_map_master_hash, &tmp_map);
+      XFREE(MTYPE_ROUTE_MAP_NAME, tmp_map.name);
+    }
+
+  if (map)
     {
       map->to_be_processed = 1;
       ret = 0;
@@ -386,8 +438,12 @@ vty_show_route_map (struct vty *vty, const char *name)
         }
       else
         {
-          vty_out (vty, "%%route-map %s not found%s", name, VTY_NEWLINE);
+          if (zlog_default)
-          return CMD_WARNING;
+            vty_out (vty, "%s", zlog_proto_names[zlog_default->protocol]);
+          if (zlog_default->instance)
+            vty_out (vty, " %d", zlog_default->instance);
+          vty_out (vty, ": 'route-map %s' not found%s", name, VTY_NEWLINE);
+          return CMD_SUCCESS;
         }
     }
   else
@@ -1049,6 +1105,7 @@ route_map_init (void)
   /* Make vector for match and set. */
   route_match_vec = vector_init (1);
   route_set_vec = vector_init (1);
+  route_map_master_hash = hash_create(route_map_hash_key_make, route_map_hash_cmp);
 }
 
 void