Add a feature arc consistency check

Verify that last node in the computed feature order matches
reality. This check doesn't make sense in all cases, so we skip it if
the newly-added vnet_feature_arc_registration_t ".last_in_arc" datum
is a NULL pointer.

Change-Id: Ia99c3e2b2da2e4780a7d5bc71670c5742a66fef2
Signed-off-by: Dave Barach <dave@barachs.net>

2 files changed, 7 insertions, 0 deletions

diff --git a/src/vnet/ip/ip4_forward.c b/src/vnet/ip/ip4_forward.c
index e011e5134d8..9963f6b1e26 100644
--- a/src/vnet/ip/ip4_forward.c
+++ b/src/vnet/ip/ip4_forward.c
@@ -711,6 +711,7 @@ VNET_FEATURE_ARC_INIT (ip4_unicast, static) =
 {
   .arc_name = "ip4-unicast",
   .start_nodes = VNET_FEATURES ("ip4-input", "ip4-input-no-checksum"),
+  .last_in_arc = "ip4-lookup",
   .arc_index_ptr = &ip4_main.lookup_main.ucast_feature_arc_index,
 };
 
@@ -796,6 +797,7 @@ VNET_FEATURE_ARC_INIT (ip4_multicast, static) =
 {
   .arc_name = "ip4-multicast",
   .start_nodes = VNET_FEATURES ("ip4-input", "ip4-input-no-checksum"),
+  .last_in_arc = "ip4-mfib-forward-lookup",
   .arc_index_ptr = &ip4_main.lookup_main.mcast_feature_arc_index,
 };
 
@@ -825,6 +827,7 @@ VNET_FEATURE_ARC_INIT (ip4_output, static) =
 {
   .arc_name = "ip4-output",
   .start_nodes = VNET_FEATURES ("ip4-rewrite", "ip4-midchain", "ip4-dvr-dpo"),
+  .last_in_arc = "interface-output",
   .arc_index_ptr = &ip4_main.lookup_main.output_feature_arc_index,
 };
 
@@ -1212,6 +1215,7 @@ VNET_FEATURE_ARC_INIT (ip4_local) =
 {
   .arc_name  = "ip4-local",
   .start_nodes = VNET_FEATURES ("ip4-local"),
+  .last_in_arc = "ip4-local-end-of-arc",
 };
 /* *INDENT-ON* */
 
diff --git a/src/vnet/ip/ip6_forward.c b/src/vnet/ip/ip6_forward.c
index 5a176435510..3c0dcbf031c 100644
--- a/src/vnet/ip/ip6_forward.c
+++ b/src/vnet/ip/ip6_forward.c
@@ -371,6 +371,7 @@ VNET_FEATURE_ARC_INIT (ip6_unicast, static) =
 {
   .arc_name  = "ip6-unicast",
   .start_nodes = VNET_FEATURES ("ip6-input"),
+  .last_in_arc = "ip6-lookup",
   .arc_index_ptr = &ip6_main.lookup_main.ucast_feature_arc_index,
 };
 
@@ -442,6 +443,7 @@ VNET_FEATURE_ARC_INIT (ip6_multicast, static) =
 {
   .arc_name  = "ip6-multicast",
   .start_nodes = VNET_FEATURES ("ip6-input"),
+  .last_in_arc = "ip6-mfib-forward-lookup",
   .arc_index_ptr = &ip6_main.lookup_main.mcast_feature_arc_index,
 };
 
@@ -468,6 +470,7 @@ VNET_FEATURE_ARC_INIT (ip6_output, static) =
 {
   .arc_name  = "ip6-output",
   .start_nodes = VNET_FEATURES ("ip6-rewrite", "ip6-midchain", "ip6-dvr-dpo"),
+  .last_in_arc = "interface-output",
   .arc_index_ptr = &ip6_main.lookup_main.output_feature_arc_index,
 };