BGP: Add dynamic update group support

This patch implements the 'update-groups' functionality in BGP. This is a
function that can significantly improve BGP performance for Update generation
and resultant network convergence. BGP Updates are formed for "groups" of
peers and then replicated and sent out to each peer rather than being formed
for each peer. Thus major BGP operations related to outbound policy
application, adj-out maintenance and actual Update packet formation
are optimized.

BGP update-groups dynamically groups peers together based on configuration
as well as run-time criteria. Thus, it is more flexible than update-formation
based on peer-groups, which relies on operator configuration.

[Note that peer-group based update formation has been introduced into BGP by
Cumulus but is currently intended only for specific releases.]

From 11098af65b2b8f9535484703e7f40330a71cbae4 Mon Sep 17 00:00:00 2001
Subject: [PATCH] updgrp commits

1 files changed, 105 insertions, 2 deletions

diff --git a/bgpd/bgp_debug.c b/bgpd/bgp_debug.c
index 9033b94df4..27d7e69782 100644
--- a/bgpd/bgp_debug.c
+++ b/bgpd/bgp_debug.c
@@ -29,6 +29,7 @@ Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
 #include "log.h"
 #include "sockunion.h"
 #include "memory.h"
+#include "queue.h"
 
 #include "bgpd/bgpd.h"
 #include "bgpd/bgp_aspath.h"
@@ -36,6 +37,7 @@ Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
 #include "bgpd/bgp_attr.h"
 #include "bgpd/bgp_debug.h"
 #include "bgpd/bgp_community.h"
+#include "bgpd/bgp_updgrp.h"
 
 unsigned long conf_bgp_debug_as4;
 unsigned long conf_bgp_debug_neighbor_events;
@@ -46,6 +48,7 @@ unsigned long conf_bgp_debug_keepalive;
 unsigned long conf_bgp_debug_update;
 unsigned long conf_bgp_debug_zebra;
 unsigned long conf_bgp_debug_nht;
+unsigned long conf_bgp_debug_update_groups;
 
 unsigned long term_bgp_debug_as4;
 unsigned long term_bgp_debug_neighbor_events;
@@ -56,6 +59,7 @@ unsigned long term_bgp_debug_keepalive;
 unsigned long term_bgp_debug_update;
 unsigned long term_bgp_debug_zebra;
 unsigned long term_bgp_debug_nht;
+unsigned long term_bgp_debug_update_groups;
 
 struct list *bgp_debug_neighbor_events_peers = NULL;
 struct list *bgp_debug_keepalive_peers = NULL;
@@ -313,6 +317,12 @@ bgp_debug_list_has_entry(struct list *list, struct peer *peer, struct prefix *p)
   return 0;
 }
 
+int
+bgp_debug_peer_updout_enabled(struct peer *peer)
+{
+  return (bgp_debug_list_has_entry(bgp_debug_update_out_peers, peer, NULL));
+}
+
 /* Dump attribute. */
 int
 bgp_dump_attr (struct peer *peer, struct attr *attr, char *buf, size_t size)
@@ -438,6 +448,15 @@ bgp_notify_print(struct peer *peer, struct bgp_notify *bgp_notify,
               bgp_notify->data ? bgp_notify->data : "");
 }
 
+static void
+bgp_debug_clear_updgrp_update_dbg(struct bgp *bgp)
+{
+  if (!bgp)
+    bgp = bgp_get_default();
+  update_group_walk (bgp, update_group_clear_update_dbg, NULL);
+}
+
+
 /* Debug option setting interface. */
 unsigned long bgp_debug_option = 0;
 
@@ -912,7 +931,19 @@ DEFUN (debug_bgp_update_direct_peer,
   if (inbound)
     bgp_debug_list_add_entry(bgp_debug_update_in_peers, peer, NULL);
   else
-    bgp_debug_list_add_entry(bgp_debug_update_out_peers, peer, NULL);
+    {
+      struct peer_af *paf;
+      int af;
+
+      bgp_debug_list_add_entry(bgp_debug_update_out_peers, peer, NULL);
+      PEERAF_FOREACH (peer, paf, af)
+        {
+          if (PAF_SUBGRP (paf))
+            {
+              UPDGRP_PEER_DBG_EN(PAF_SUBGRP(paf)->update_group);
+            }
+        }
+    }
 
   if (vty->node == CONFIG_NODE)
     {
@@ -1006,6 +1037,20 @@ DEFUN (no_debug_bgp_update_direct_peer,
               vty_out (vty, "BGP updates debugging (outbound) is off%s", VTY_NEWLINE);
             }
         }
+
+      if (found_peer)
+        {
+          struct peer_af *paf;
+          int af;
+
+          PEERAF_FOREACH (peer, paf, af)
+            {
+              if (PAF_SUBGRP (paf))
+                {
+                  UPDGRP_PEER_DBG_DIS(PAF_SUBGRP(paf)->update_group);
+                }
+            }
+        }
     }
 
   if (found_peer)
@@ -1133,6 +1178,8 @@ DEFUN (no_debug_bgp_update,
   bgp_debug_list_free(bgp_debug_update_out_peers);
   bgp_debug_list_free(bgp_debug_update_prefixes);
 
+  bgp_debug_clear_updgrp_update_dbg(vty->index);
+
   if (vty->node == CONFIG_NODE)
     {
       DEBUG_OFF (update, UPDATE_IN);
@@ -1281,6 +1328,42 @@ DEFUN (no_debug_bgp_zebra_prefix,
   return CMD_SUCCESS;
 }
 
+/* debug bgp update-groups */
+DEFUN (debug_bgp_update_groups,
+       debug_bgp_update_groups_cmd,
+       "debug bgp update-groups",
+       DEBUG_STR
+       BGP_STR
+       "BGP update-groups\n")
+{
+  if (vty->node == CONFIG_NODE)
+    DEBUG_ON (update_groups, UPDATE_GROUPS);
+  else
+    {
+      TERM_DEBUG_ON (update_groups, UPDATE_GROUPS);
+      vty_out (vty, "BGP update-groups debugging is on%s", VTY_NEWLINE);
+    }
+  return CMD_SUCCESS;
+}
+
+DEFUN (no_debug_bgp_update_groups,
+       no_debug_bgp_update_groups_cmd,
+       "no debug bgp update-groups",
+       NO_STR
+       DEBUG_STR
+       BGP_STR
+       "BGP update-groups\n")
+{
+  if (vty->node == CONFIG_NODE)
+    DEBUG_OFF (update_groups, UPDATE_GROUPS);
+  else
+    {
+      TERM_DEBUG_OFF (update_groups, UPDATE_GROUPS);
+      vty_out (vty, "BGP update-groups debugging is off%s", VTY_NEWLINE);
+    }
+  return CMD_SUCCESS;
+}
+
 DEFUN (no_debug_bgp,
        no_debug_bgp_cmd,
        "no debug bgp",
@@ -1295,6 +1378,8 @@ DEFUN (no_debug_bgp,
   bgp_debug_list_free(bgp_debug_update_prefixes);
   bgp_debug_list_free(bgp_debug_zebra_prefixes);
 
+  bgp_debug_clear_updgrp_update_dbg(vty->index);
+
   TERM_DEBUG_OFF (keepalive, KEEPALIVE);
   TERM_DEBUG_OFF (update, UPDATE_IN);
   TERM_DEBUG_OFF (update, UPDATE_OUT);
@@ -1350,6 +1435,9 @@ DEFUN (show_debugging_bgp,
     bgp_debug_list_print (vty, "  BGP zebra debugging is on",
                           bgp_debug_zebra_prefixes);
 
+  if (BGP_DEBUG (update_groups, UPDATE_GROUPS))
+    vty_out (vty, "  BGP update-groups debugging is on%s", VTY_NEWLINE);
+
   vty_out (vty, "%s", VTY_NEWLINE);
   return CMD_SUCCESS;
 }
@@ -1411,6 +1499,12 @@ bgp_config_write_debug (struct vty *vty)
       write++;
     }
 
+    if (CONF_BGP_DEBUG (update_groups, UPDATE_GROUPS))
+    {
+      vty_out (vty, "debug bgp update-groups%s", VTY_NEWLINE);
+      write++;
+    }
+
   return write;
 }
 
@@ -1445,6 +1539,8 @@ bgp_debug_init (void)
   install_element (CONFIG_NODE, &debug_bgp_update_direct_cmd);
   install_element (ENABLE_NODE, &debug_bgp_zebra_cmd);
   install_element (CONFIG_NODE, &debug_bgp_zebra_cmd);
+  install_element (ENABLE_NODE, &debug_bgp_update_groups_cmd);
+  install_element (CONFIG_NODE, &debug_bgp_update_groups_cmd);
 
   /* deb bgp updates [in|out] A.B.C.D */
   install_element (ENABLE_NODE, &debug_bgp_update_direct_peer_cmd);
@@ -1491,6 +1587,8 @@ bgp_debug_init (void)
   install_element (CONFIG_NODE, &no_debug_bgp_update_cmd);
   install_element (ENABLE_NODE, &no_debug_bgp_zebra_cmd);
   install_element (CONFIG_NODE, &no_debug_bgp_zebra_cmd);
+  install_element (ENABLE_NODE, &no_debug_bgp_update_groups_cmd);
+  install_element (CONFIG_NODE, &no_debug_bgp_update_groups_cmd);
   install_element (ENABLE_NODE, &no_debug_bgp_cmd);
 }
 
@@ -1577,7 +1675,8 @@ bgp_debug_keepalive (struct peer *peer)
 }
 
 int
-bgp_debug_update (struct peer *peer, struct prefix *p, unsigned int inbound)
+bgp_debug_update (struct peer *peer, struct prefix *p,
+                  struct update_group *updgrp, unsigned int inbound)
 {
   if (inbound)
     {
@@ -1593,6 +1692,10 @@ bgp_debug_update (struct peer *peer, struct prefix *p, unsigned int inbound)
                               BGP_DEBUG_UPDATE_OUT,
                               bgp_debug_update_out_peers))
         return 1;
+
+      /* Check if update debugging implicitly enabled for the group. */
+      if (updgrp && UPDGRP_DBG_ON(updgrp))
+        return 1;
     }