infra: add drop counter "no_headroom"

modules/infra/datapath/drop.c

@@ -19,3 +19,6 @@ drop_packets(struct rte_graph *graph, struct rte_node *node, void **objs, uint16
 
 	return nb_objs;
 }
+
+// Global drop counters, used by multiple nodes
+GR_DROP_REGISTER(error_no_headroom);

modules/infra/datapath/eth_output.c

@@ -17,6 +17,7 @@
 enum {
 	TX = 0,
 	INVAL,
+	NO_HEADROOM,
 	NB_EDGES,
 };
 
@@ -38,6 +39,10 @@ eth_output_process(struct rte_graph *graph, struct rte_node *node, void **objs,
 		case GR_IFACE_TYPE_VLAN:
 			sub = (struct iface_info_vlan *)priv->iface->info;
 			vlan = (struct rte_vlan_hdr *)rte_pktmbuf_prepend(mbuf, sizeof(*vlan));
+			if (unlikely(vlan == NULL)) {
+				rte_node_enqueue_x1(graph, node, NO_HEADROOM, mbuf);
+				continue;
+			}
 			vlan->vlan_tci = rte_cpu_to_be_16(sub->vlan_id);
 			vlan->eth_proto = priv->ether_type;
 			priv->ether_type = rte_cpu_to_be_16(RTE_ETHER_TYPE_VLAN);
@@ -55,6 +60,10 @@ eth_output_process(struct rte_graph *graph, struct rte_node *node, void **objs,
 		}
 
 		eth = (struct rte_ether_hdr *)rte_pktmbuf_prepend(mbuf, sizeof(*eth));
+		if (unlikely(eth == NULL)) {
+			rte_node_enqueue_x1(graph, node, NO_HEADROOM, mbuf);
+			continue;
+		}
 		rte_ether_addr_copy(&priv->dst, &eth->dst_addr);
 		rte_ether_addr_copy(src_mac, &eth->src_addr);
 		eth->ether_type = priv->ether_type;
@@ -75,6 +84,7 @@ static struct rte_node_register node= {
 	.next_nodes = {
 		[TX] = "port_tx",
 		[INVAL] = "eth_output_inval",
+		[NO_HEADROOM] = "error_no_headroom",
 	},
 };
 

modules/ip/datapath/icmp_output.c

@@ -16,6 +16,7 @@
 
 enum {
 	OUTPUT = 0,
+	NO_HEADROOM,
 	EDGE_COUNT,
 };
 
@@ -35,14 +36,17 @@ icmp_output_process(struct rte_graph *graph, struct rte_node *node, void **objs,
 		icmp->icmp_cksum = ~rte_raw_cksum(icmp, local_data->len);
 
 		ip = (struct rte_ipv4_hdr *)rte_pktmbuf_prepend(mbuf, sizeof(*ip));
+		if (unlikely(ip == NULL)) {
+			rte_node_enqueue_x1(graph, node, NO_HEADROOM, mbuf);
+			continue;
+		}
 		ip_set_fields(ip, local_data);
 		ip_output_mbuf_data(mbuf)->nh = ip4_route_lookup(
 			local_data->vrf_id, local_data->dst
 		);
+		rte_node_enqueue_x1(graph, node, OUTPUT, mbuf);
 	}
 
-	rte_node_enqueue(graph, node, OUTPUT, objs, nb_objs);
-
 	return nb_objs;
 }
 
@@ -54,6 +58,7 @@ static struct rte_node_register icmp_output_node = {
 	.nb_edges = EDGE_COUNT,
 	.next_nodes = {
 		[OUTPUT] = "ip_output",
+		[NO_HEADROOM] = "error_no_headroom",
 	},
 };
 

modules/ipip/datapath_out.c

@@ -22,6 +22,7 @@
 enum {
 	IP_OUTPUT = 0,
 	NO_TUNNEL,
+	NO_HEADROOM,
 	EDGE_COUNT,
 };
 
@@ -56,6 +57,10 @@ ipip_output_process(struct rte_graph *graph, struct rte_node *node, void **objs,
 		tunnel.vrf_id = iface->vrf_id;
 		tunnel.proto = IPPROTO_IPIP;
 		outer = (struct rte_ipv4_hdr *)rte_pktmbuf_prepend(mbuf, sizeof(*outer));
+		if (unlikely(outer == NULL)) {
+			rte_node_enqueue_x1(graph, node, NO_HEADROOM, mbuf);
+			continue;
+		}
 		ip_set_fields(outer, &tunnel);
 
 		// Resolve nexthop for the encapsulated packet.
@@ -84,6 +89,7 @@ static struct rte_node_register ipip_output_node = {
 	.next_nodes = {
 		[IP_OUTPUT] = "ip_output",
 		[NO_TUNNEL] = "ipip_output_no_tunnel",
+		[NO_HEADROOM] = "error_no_headroom",
 	},
 };