bgpd: Adding changes for Selection Deferral Timer config cmd

and DS.

* Added config commands and data structures for deferral timer
configuration and processing.
Cmd : bgp graceful-restart select-defer-time (0-3600)
Cmd : no bgp graceful-restart select-defertime (0-3600)

Signed-off-by: Biswajit Sadhu <sadhub@vmware.com>
Signed-off-by: Soman K S <somanks@vmware.com>

bgpd/bgp_vty.c

@@ -2214,6 +2214,28 @@ DEFUN (bgp_graceful_restart_restart_time,
 	return CMD_SUCCESS;
 }
 
+DEFUN (bgp_graceful_restart_select_defer_time,
+       bgp_graceful_restart_select_defer_time_cmd,
+       "bgp graceful-restart select-defer-time (0-3600)",
+       "BGP specific commands\n"
+       "Graceful restart capability parameters\n"
+       "Set the time to defer the BGP route selection after restart\n"
+       "Delay value (seconds, 0 - disable)\n")
+{
+	VTY_DECLVAR_CONTEXT(bgp, bgp);
+	int idx_number = 3;
+	uint32_t defer_time;
+
+	defer_time = strtoul(argv[idx_number]->arg, NULL, 10);
+	bgp->select_defer_time = defer_time;
+	if (defer_time == 0)
+		bgp_flag_set(bgp, BGP_FLAG_SELECT_DEFER_DISABLE);
+	else
+		bgp_flag_unset(bgp, BGP_FLAG_SELECT_DEFER_DISABLE);
+
+	return CMD_SUCCESS;
+}
+
 DEFUN (no_bgp_graceful_restart_stalepath_time,
 		no_bgp_graceful_restart_stalepath_time_cmd,
 		"no bgp graceful-restart stalepath-time [(1-4095)]",
@@ -2244,6 +2266,23 @@ DEFUN (no_bgp_graceful_restart_restart_time,
 	return CMD_SUCCESS;
 }
 
+DEFUN (no_bgp_graceful_restart_select_defer_time,
+       no_bgp_graceful_restart_select_defer_time_cmd,
+       "no bgp graceful-restart select-defer-time [(0-3600)]",
+       NO_STR
+       "BGP specific commands\n"
+       "Graceful restart capability parameters\n"
+       "Set the time to defer the BGP route selection after restart\n"
+       "Delay value (seconds)\n")
+{
+	VTY_DECLVAR_CONTEXT(bgp, bgp);
+
+	bgp->select_defer_time = BGP_DEFAULT_SELECT_DEFERRAL_TIME;
+	bgp_flag_unset(bgp, BGP_FLAG_SELECT_DEFER_DISABLE);
+
+	return CMD_SUCCESS;
+}
+
 DEFUN (bgp_graceful_restart_preserve_fw,
 		bgp_graceful_restart_preserve_fw_cmd,
 		"bgp graceful-restart preserve-fw-state",
@@ -14379,6 +14418,27 @@ static void bgp_config_write_peer_global(struct vty *vty, struct bgp *bgp,
 	if (peer->as_path_loop_detection)
 		vty_out(vty, " neighbor %s sender-as-path-loop-detection\n",
 			addr);
+
+	if (!CHECK_FLAG(peer->peer_gr_new_status_flag,
+		PEER_GRACEFUL_RESTART_NEW_STATE_INHERIT)) {
+
+		if (CHECK_FLAG(peer->peer_gr_new_status_flag,
+				PEER_GRACEFUL_RESTART_NEW_STATE_HELPER)) {
+			vty_out(vty,
+				" neighbor %s graceful-restart-helper\n", addr);
+		} else if (CHECK_FLAG(peer->peer_gr_new_status_flag,
+				PEER_GRACEFUL_RESTART_NEW_STATE_RESTART)) {
+			vty_out(vty,
+				" neighbor %s graceful-restart\n", addr);
+		} else if ((!(CHECK_FLAG(peer->peer_gr_new_status_flag,
+				PEER_GRACEFUL_RESTART_NEW_STATE_HELPER))
+				&& !(CHECK_FLAG(peer->peer_gr_new_status_flag,
+				PEER_GRACEFUL_RESTART_NEW_STATE_RESTART)))) {
+			vty_out(vty,
+				" neighbor %s graceful-restart-disable\n",
+					addr);
+		}
+	}
 }
 
 /* BGP peer configuration display function. */
@@ -14905,12 +14965,22 @@ int bgp_config_write(struct vty *vty)
 			vty_out(vty,
 				" bgp graceful-restart stalepath-time %u\n",
 				bgp->stalepath_time);
+
 		if (bgp->restart_time != BGP_DEFAULT_RESTART_TIME)
 			vty_out(vty, " bgp graceful-restart restart-time %u\n",
 				bgp->restart_time);
-		if (bgp_flag_check(bgp, BGP_FLAG_GRACEFUL_RESTART))
+
+		if (bgp->select_defer_time != BGP_DEFAULT_SELECT_DEFERRAL_TIME)
+			vty_out(vty,
+				" bgp graceful-restart select-defer-time %u\n",
+				bgp->select_defer_time);
+
+		if (bgp_global_gr_mode_get(bgp) == GLOBAL_GR)
 			vty_out(vty, " bgp graceful-restart\n");
 
+		if (bgp_global_gr_mode_get(bgp) == GLOBAL_DISABLE)
+			vty_out(vty, " bgp graceful-restart-disable\n");
+
 		/* BGP graceful-shutdown */
 		if (bgp_flag_check(bgp, BGP_FLAG_GRACEFUL_SHUTDOWN))
 			vty_out(vty, " bgp graceful-shutdown\n");
@@ -15322,7 +15392,8 @@ void bgp_vty_init(void)
 	install_element(BGP_NODE, &no_bgp_graceful_restart_stalepath_time_cmd);
 	install_element(BGP_NODE, &bgp_graceful_restart_restart_time_cmd);
 	install_element(BGP_NODE, &no_bgp_graceful_restart_restart_time_cmd);
-
+	install_element(BGP_NODE, &bgp_graceful_restart_select_defer_time_cmd);
+	install_element(BGP_NODE, &no_bgp_graceful_restart_select_defer_time_cmd);
 	install_element(BGP_NODE, &bgp_graceful_restart_preserve_fw_cmd);
 	install_element(BGP_NODE, &no_bgp_graceful_restart_preserve_fw_cmd);
 

bgpd/bgpd.c

@@ -3017,6 +3017,12 @@ static struct bgp *bgp_create(as_t *as, const char *name,
 				      multipath_num, 0);
 		bgp_maximum_paths_set(bgp, afi, safi, BGP_PEER_IBGP,
 				      multipath_num, 0);
+		/* Initialize graceful restart info */
+		bgp->gr_info[afi][safi].eor_required = 0;
+		bgp->gr_info[afi][safi].eor_received = 0;
+		bgp->gr_info[afi][safi].t_select_deferral = NULL;
+		bgp->gr_info[afi][safi].t_route_select = NULL;
+		bgp->gr_info[afi][safi].route_list = list_new();
 	}
 
 	bgp->v_update_delay = BGP_UPDATE_DELAY_DEF;
@@ -3026,6 +3032,7 @@ static struct bgp *bgp_create(as_t *as, const char *name,
 	bgp_timers_unset(bgp);
 	bgp->restart_time = BGP_DEFAULT_RESTART_TIME;
 	bgp->stalepath_time = BGP_DEFAULT_STALEPATH_TIME;
+	bgp->select_defer_time = BGP_DEFAULT_SELECT_DEFERRAL_TIME;
 	bgp->dynamic_neighbors_limit = BGP_DYNAMIC_NEIGHBORS_LIMIT_DEFAULT;
 	bgp->dynamic_neighbors_count = 0;
 	bgp->ebgp_requires_policy = DEFAULT_EBGP_POLICY_DISABLED;
@@ -3351,7 +3358,9 @@ int bgp_delete(struct bgp *bgp)
 	struct listnode *node, *next;
 	struct vrf *vrf;
 	afi_t afi;
+	safi_t safi;
 	int i;
+	struct graceful_restart_info *gr_info;
 
 	assert(bgp);
 
@@ -3365,6 +3374,19 @@ int bgp_delete(struct bgp *bgp)
 	/* Set flag indicating bgp instance delete in progress */
 	bgp_flag_set(bgp, BGP_FLAG_DELETE_IN_PROGRESS);
 
+	/* Delete the graceful restart info */
+	FOREACH_AFI_SAFI (afi, safi) {
+		gr_info = &bgp->gr_info[afi][safi];
+		if (gr_info) {
+			BGP_TIMER_OFF(gr_info->t_select_deferral);
+			gr_info->t_select_deferral = NULL;
+			BGP_TIMER_OFF(gr_info->t_route_select);
+			gr_info->t_route_select = NULL;
+			if (gr_info->route_list)
+				list_delete(&gr_info->route_list);
+		}
+	}
+
 	if (BGP_DEBUG(zebra, ZEBRA)) {
 		if (bgp->inst_type == BGP_INSTANCE_TYPE_DEFAULT)
 			zlog_debug("Deleting Default VRF");

bgpd/bgpd.h

@@ -407,7 +407,7 @@ struct bgp {
 #define BGP_FLAG_GR_PRESERVE_FWD          (1 << 20)
 #define BGP_FLAG_GRACEFUL_SHUTDOWN        (1 << 21)
 #define BGP_FLAG_DELETE_IN_PROGRESS       (1 << 22)
-
+#define BGP_FLAG_SELECT_DEFER_DISABLE     (1 << 23)
 
 	enum global_mode GLOBAL_GR_FSM[GLOBAL_MODE][EVENT_CMD];
 	enum global_mode global_gr_present_state;
@@ -508,7 +508,8 @@ struct bgp {
 	uint32_t stalepath_time;
 	uint32_t select_defer_time;
 	struct graceful_restart_info gr_info[AFI_MAX][SAFI_MAX];
-
+#define BGP_ROUTE_SELECT_DELAY 1
+#define BGP_MAX_BEST_ROUTE_SELECT 10000
 	/* Maximum-paths configuration */
 	struct bgp_maxpaths_cfg {
 		uint16_t maxpaths_ebgp;
@@ -635,6 +636,13 @@ DECLARE_HOOK(bgp_inst_config_write,
 		(struct bgp *bgp, struct vty *vty),
 		(bgp, vty))
 
+	/* Thread callback information */
+	struct afi_safi_info {
+		afi_t afi;
+		safi_t safi;
+		struct bgp *bgp;
+	};
+
 #define BGP_ROUTE_ADV_HOLD(bgp) (bgp->main_peers_update_hold)
 
 #define IS_BGP_INST_KNOWN_TO_ZEBRA(bgp)                                        \
@@ -642,6 +650,9 @@ DECLARE_HOOK(bgp_inst_config_write,
 	 || (bgp->inst_type == BGP_INSTANCE_TYPE_VRF                           \
 	     && bgp->vrf_id != VRF_UNKNOWN))
 
+#define BGP_SELECT_DEFER_DISABLE(bgp)                                  \
+       (bgp_flag_check(bgp, BGP_FLAG_SELECT_DEFER_DISABLE))
+
 /* BGP peer-group support. */
 struct peer_group {
 	/* Name of the peer-group. */
@@ -1553,6 +1564,7 @@ struct bgp_nlri {
 /* BGP graceful restart  */
 #define BGP_DEFAULT_RESTART_TIME               120
 #define BGP_DEFAULT_STALEPATH_TIME             360
+#define BGP_DEFAULT_SELECT_DEFERRAL_TIME       360
 
 /* BGP uptime string length.  */
 #define BGP_UPTIME_LEN 25