Improve feature arc order constraint specification

Add the VNET_FEATURE_ARC_ORDER macro, which allows specification of
bulk order constraints. Here's an example:

VNET_FEATURE_ARC_ORDER(ip4_unicast_arc_order, static) = {
  .arc_name = "ip4-unicast",
  .node_names = VNET_FEATURES ("ip4-flow-classify",
                               "ip4-inacl",
                               "ip4-source-check-via-rx",
                               "ip4-source-check-via-any",
                               "ip4-source-and-port-range-check-rx",
                               "ip4-policer-classify",
                               "ipsec4-input",
                               "vpath-input-ip4",
                               "ip4-vxlan-bypass",
                               "ip4-not-enabled",
                               "ip4-lookup"),
};

Simply list feature nodes in the desired order, and you're
done. Multiple macro instances per are are fine / expected /
tested.

Under the covers: generate "a before b" tuples by chain-dragging
across the ordered list. No need to touch existing per-feature
constraints.

Fixed a long-broken "you lose!" error message.

Change-Id: I259282e426fd305e22c8d65886787c41a1d348d3
Signed-off-by: Dave Barach <dave@barachs.net>

1 files changed, 32 insertions, 5 deletions

diff --git a/src/vnet/feature/feature.c b/src/vnet/feature/feature.c
index 6525bcbdce5..2cdbcff88c8 100644
--- a/src/vnet/feature/feature.c
+++ b/src/vnet/feature/feature.c
@@ -24,6 +24,7 @@ vnet_feature_init (vlib_main_t * vm)
   vnet_feature_main_t *fm = &feature_main;
   vnet_feature_registration_t *freg;
   vnet_feature_arc_registration_t *areg;
+  vnet_feature_constraint_registration_t *creg;
   u32 arc_index = 0;
 
   fm->arc_index_by_name = hash_create_string (0, sizeof (uword));
@@ -58,6 +59,7 @@ vnet_feature_init (vlib_main_t * vm)
   vec_validate (fm->next_feature_by_name, arc_index - 1);
   vec_validate (fm->sw_if_index_has_features, arc_index - 1);
   vec_validate (fm->feature_count_by_sw_if_index, arc_index - 1);
+  vec_validate (fm->next_constraint_by_arc, arc_index - 1);
 
   freg = fm->next_feature;
   while (freg)
@@ -82,6 +84,31 @@ vnet_feature_init (vlib_main_t * vm)
       freg = next;
     }
 
+  /* Move bulk constraints to the constraint by arc lists */
+  creg = fm->next_constraint;
+  while (creg)
+    {
+      vnet_feature_constraint_registration_t *next;
+      uword *p = hash_get_mem (fm->arc_index_by_name, creg->arc_name);
+      if (p == 0)
+	{
+	  /* Don't start vpp with broken features arcs */
+	  clib_warning ("Unknown feature arc '%s'", creg->arc_name);
+	  os_exit (1);
+	}
+
+      areg = uword_to_pointer (p[0], vnet_feature_arc_registration_t *);
+      arc_index = areg->feature_arc_index;
+
+      next = creg->next;
+      creg->next_in_arc = fm->next_constraint_by_arc[arc_index];
+      fm->next_constraint_by_arc[arc_index] = creg;
+
+      /* next */
+      creg = next;
+    }
+
+
   areg = fm->next_arc;
   while (areg)
     {
@@ -92,11 +119,11 @@ vnet_feature_init (vlib_main_t * vm)
       arc_index = areg->feature_arc_index;
       cm = &fm->feature_config_mains[arc_index];
       vcm = &cm->config_main;
-      if ((error = vnet_feature_arc_init (vm, vcm,
-					  areg->start_nodes,
-					  areg->n_start_nodes,
-					  fm->next_feature_by_arc[arc_index],
-					  &fm->feature_nodes[arc_index])))
+      if ((error = vnet_feature_arc_init
+	   (vm, vcm, areg->start_nodes, areg->n_start_nodes,
+	    fm->next_feature_by_arc[arc_index],
+	    fm->next_constraint_by_arc[arc_index],
+	    &fm->feature_nodes[arc_index])))
 	{
 	  clib_error_report (error);
 	  os_exit (1);