Mtrie optimisations

1 - make the default route non-special, i.e. like any other less specific route. Consequently, all buckets have a valid valid index of either a leaf or a ply. Checks for special indeices in the data-path can thus be removed.
2 - since all leaves are now 'real' i.e. they represent a real load-balance object, to tell if a ply slot is 'empty' requeirs chekcing that the prefix length of the leaf occupying the slot is slot than the minium value for that ply.
3 - when removing a leaf find the cover first, then recurse down the ply and replace the old leaf with the cover. This saves us a ply walk.

Change-Id: Idd523019e8bb1b6ef527b1f5279a5e24bcf18332
Signed-off-by: Neale Ranns <nranns@cisco.com>

1 files changed, 0 insertions, 12 deletions

diff --git a/src/vnet/adj/adj.c b/src/vnet/adj/adj.c
index 9a01e89d660..c1d036a0e8b 100644
--- a/src/vnet/adj/adj.c
+++ b/src/vnet/adj/adj.c
@@ -20,13 +20,6 @@
 #include <vnet/adj/adj_mcast.h>
 #include <vnet/fib/fib_node_list.h>
 
-/*
- * Special Adj with index zero. we need to define this since the v4 mtrie
- * assumes an index of 0 implies the ply is empty. therefore all 'real'
- * adjs need a non-zero index.
- */
-static ip_adjacency_t *special_v4_miss_adj_with_index_zero;
-
 /* Adjacency packet/byte counters indexed by adjacency index. */
 vlib_combined_counter_main_t adjacency_counters;
 
@@ -426,11 +419,6 @@ adj_module_init (vlib_main_t * vm)
     adj_midchain_module_init();
     adj_mcast_module_init();
 
-    /*
-     * one special adj to reserve index 0
-     */
-    special_v4_miss_adj_with_index_zero = adj_alloc(FIB_PROTOCOL_IP4);
-
     return (NULL);
 }