fabricd: add flooding algorithm debugging

Add a command `debug openfabric flooding` to allow verification of
correct operation of the OpenFabric flooding optimization algorithm.

Signed-off-by: Christian Franke <chris@opensourcerouting.org>

isisd/fabricd.c

@@ -491,6 +491,13 @@ static void move_to_dnr(struct isis_lsp *lsp, struct neighbor_entry *n)
 	struct isis_adjacency *adj = listnode_head(n->vertex->Adj_N);
 
 	n->present = false;
+
+	if (isis->debugs & DEBUG_FABRICD_FLOODING) {
+		char buff[PREFIX2STR_BUFFER];
+		zlog_debug("OpenFabric: Adding %s to DNR",
+			   vid2string(n->vertex, buff, sizeof(buff)));
+	}
+
 	if (adj) {
 		isis_tx_queue_add(adj->circuit->tx_queue, lsp,
 				  TX_LSP_CIRCUIT_SCOPED);
@@ -502,6 +509,13 @@ static void move_to_rf(struct isis_lsp *lsp, struct neighbor_entry *n)
 	struct isis_adjacency *adj = listnode_head(n->vertex->Adj_N);
 
 	n->present = false;
+
+	if (isis->debugs & DEBUG_FABRICD_FLOODING) {
+		char buff[PREFIX2STR_BUFFER];
+		zlog_debug("OpenFabric: Adding %s to RF",
+			   vid2string(n->vertex, buff, sizeof(buff)));
+	}
+
 	if (adj) {
 		isis_tx_queue_add(adj->circuit->tx_queue, lsp,
 				  TX_LSP_NORMAL);
@@ -524,12 +538,24 @@ static void handle_firsthops(struct hash_backet *backet, void *arg)
 	struct neighbor_entry *n;
 
 	n = neighbor_entry_lookup_list(f->neighbors, vertex->N.id);
-	if (n)
+	if (n) {
+		if (isis->debugs & DEBUG_FABRICD_FLOODING) {
+			char buff[PREFIX2STR_BUFFER];
+			zlog_debug("Removing %s from NL as its in the reverse path",
+				   vid2string(vertex, buff, sizeof(buff)));
+		}
 		n->present = false;
+	}
 
 	n = neighbor_entry_lookup_hash(f->neighbors_neighbors, vertex->N.id);
-	if (n)
+	if (n) {
+		if (isis->debugs & DEBUG_FABRICD_FLOODING) {
+			char buff[PREFIX2STR_BUFFER];
+			zlog_debug("Removing %s from NN as its in the reverse path",
+				   vid2string(vertex, buff, sizeof(buff)));
+		}
 		n->present = false;
+	}
 }
 
 void fabricd_lsp_flood(struct isis_lsp *lsp)
@@ -540,6 +566,11 @@ void fabricd_lsp_flood(struct isis_lsp *lsp)
 	void *cursor = NULL;
 	struct neighbor_entry *n;
 
+	if (isis->debugs & DEBUG_FABRICD_FLOODING) {
+		zlog_debug("OpenFabric: Flooding LSP %s",
+			   rawlspid_print(lsp->hdr.lsp_id));
+	}
+
 	/* Mark all elements in NL as present and move T0s into DNR */
 	while (!skiplist_next(f->neighbors, NULL, (void **)&n, &cursor)) {
 		n->present = true;
@@ -552,6 +583,11 @@ void fabricd_lsp_flood(struct isis_lsp *lsp)
 		    || lsp->tlvs->spine_leaf->tier != 0)
 			continue;
 
+		if (isis->debugs & DEBUG_FABRICD_FLOODING) {
+			zlog_debug("Moving %s to DNR because it's T0",
+			           rawlspid_print(lsp->hdr.lsp_id));
+		}
+
 		move_to_dnr(lsp, n);
 	}
 
@@ -575,10 +611,22 @@ void fabricd_lsp_flood(struct isis_lsp *lsp)
 
 		struct isis_lsp *nlsp = lsp_for_vertex(f->spftree, n->vertex);
 		if (!nlsp || !nlsp->tlvs) {
+			if (isis->debugs & DEBUG_FABRICD_FLOODING) {
+				char buff[PREFIX2STR_BUFFER];
+				zlog_debug("Moving %s to DNR as it has no LSP",
+					   vid2string(n->vertex, buff, sizeof(buff)));
+			}
+
 			move_to_dnr(lsp, n);
 			continue;
 		}
 
+		if (isis->debugs & DEBUG_FABRICD_FLOODING) {
+			char buff[PREFIX2STR_BUFFER];
+			zlog_debug("Considering %s from NL...",
+				   vid2string(n->vertex, buff, sizeof(buff)));
+		}
+
 		/* For all neighbors of the NL IS check whether they are present
 		 * in NN. If yes, remove from NN and set need_reflood. */
 		bool need_reflood = false;
@@ -591,6 +639,12 @@ void fabricd_lsp_flood(struct isis_lsp *lsp)
 							er->id);
 
 			if (nn) {
+				if (isis->debugs & DEBUG_FABRICD_FLOODING) {
+					char buff[PREFIX2STR_BUFFER];
+					zlog_debug("Found neighbor %s in NN, removing it from NN and setting reflood.",
+						   vid2string(nn->vertex, buff, sizeof(buff)));
+				}
+
 				nn->present = false;
 				need_reflood = true;
 			}
@@ -601,4 +655,8 @@ void fabricd_lsp_flood(struct isis_lsp *lsp)
 		else
 			move_to_dnr(lsp, n);
 	}
+
+	if (isis->debugs & DEBUG_FABRICD_FLOODING) {
+		zlog_debug("OpenFabric: Flooding algorithm complete.");
+	}
 }

isisd/isis_spf.c

@@ -162,8 +162,7 @@ static const char *vtype2string(enum vertextype vtype)
 	return NULL; /* Not reached */
 }
 
-#define VID2STR_BUFFER SRCDEST2STR_BUFFER
+const char *vid2string(struct isis_vertex *vertex, char *buff, int size)
-static const char *vid2string(struct isis_vertex *vertex, char *buff, int size)
 {
 	if (VTYPE_IS(vertex->type) || VTYPE_ES(vertex->type)) {
 		return print_sys_hostname(vertex->N.id);

isisd/isis_spf.h

@@ -40,5 +40,4 @@ void isis_spf_print(struct isis_spftree *spftree, struct vty *vty);
 struct isis_spftree *isis_run_hopcount_spf(struct isis_area *area,
 					   uint8_t *sysid,
 					   struct isis_spftree *spftree);
-
 #endif /* _ZEBRA_ISIS_SPF_H */

isisd/isis_spf_private.h

@@ -354,4 +354,7 @@ static struct isis_lsp *lsp_for_vertex(struct isis_spftree *spftree,
 	return NULL;
 }
 
+#define VID2STR_BUFFER SRCDEST2STR_BUFFER
+const char *vid2string(struct isis_vertex *vertex, char *buff, int size);
+
 #endif

isisd/isis_vty_fabricd.c

@@ -55,8 +55,40 @@ DEFUN (no_fabric_tier,
 	return CMD_SUCCESS;
 }
 
+DEFUN (debug_fabric_flooding,
+       debug_fabric_flooding_cmd,
+       "debug openfabric flooding",
+       DEBUG_STR
+       PROTO_HELP
+       "Flooding optimization algorithm\n")
+{
+	isis->debugs |= DEBUG_FABRICD_FLOODING;
+	print_debug(vty, DEBUG_FABRICD_FLOODING, 1);
+
+	return CMD_SUCCESS;
+}
+
+DEFUN (no_debug_fabric_flooding,
+       no_debug_fabric_flooding_cmd,
+       "no debug openfabric flooding",
+       NO_STR
+       UNDEBUG_STR
+       PROTO_HELP
+       "Flooding optimization algorithm\n")
+{
+	isis->debugs &= ~DEBUG_FABRICD_FLOODING;
+	print_debug(vty, DEBUG_FABRICD_FLOODING, 0);
+
+	return CMD_SUCCESS;
+}
+
+
 void isis_vty_daemon_init(void)
 {
 	install_element(ROUTER_NODE, &fabric_tier_cmd);
 	install_element(ROUTER_NODE, &no_fabric_tier_cmd);
+	install_element(ENABLE_NODE, &debug_fabric_flooding_cmd);
+	install_element(ENABLE_NODE, &no_debug_fabric_flooding_cmd);
+	install_element(CONFIG_NODE, &debug_fabric_flooding_cmd);
+	install_element(CONFIG_NODE, &no_debug_fabric_flooding_cmd);
 }

isisd/isisd.c

@@ -744,6 +744,8 @@ void print_debug(struct vty *vty, int flags, int onoff)
 		vty_out(vty, "IS-IS LSP generation debugging is %s\n", onoffs);
 	if (flags & DEBUG_LSP_SCHED)
 		vty_out(vty, "IS-IS LSP scheduling debugging is %s\n", onoffs);
+	if (flags & DEBUG_FABRICD_FLOODING)
+		vty_out(vty, "OpenFabric Flooding debugging is %s\n", onoffs);
 }
 
 DEFUN_NOSH (show_debugging,
@@ -825,6 +827,10 @@ static int config_write_debug(struct vty *vty)
 		vty_out(vty, "debug " PROTO_NAME " lsp-sched\n");
 		write++;
 	}
+	if (flags & DEBUG_FABRICD_FLOODING) {
+		vty_out(vty, "debug " PROTO_NAME " flooding\n");
+		write++;
+	}
 	write += spf_backoff_write_config(vty);
 
 	return write;

isisd/isisd.h

@@ -209,6 +209,7 @@ extern struct thread_master *master;
 #define DEBUG_PACKET_DUMP                (1<<12)
 #define DEBUG_LSP_GEN                    (1<<13)
 #define DEBUG_LSP_SCHED                  (1<<14)
+#define DEBUG_FABRICD_FLOODING           (1<<15)
 
 #define lsp_debug(...)                                                         \
 	do {                                                                   \