*: introduce new rb-tree to optimize interface lookup by ifindex

Performance tests showed that, when running on a system with a large
number of interfaces, some daemons would spend a considerable amount
of time in the if_lookup_by_index() function. Introduce a new rb-tree
to solve this problem.

With this change, we need to use the if_set_index() function whenever
we want to change the ifindex of an interface. This is necessary to
ensure that the 'ifaces_by_index' rb-tree is updated accordingly. The
return value of all insert/remove operations in the interface rb-trees
is checked to ensure that an error is logged if a corruption is
detected.

Signed-off-by: Renato Westphal <renato@opensourcerouting.org>

1 files changed, 1 insertions, 0 deletions

diff --git a/lib/vrf.h b/lib/vrf.h
index 5309100bd5..8bfdc87689 100644
--- a/lib/vrf.h
+++ b/lib/vrf.h
@@ -79,6 +79,7 @@ struct vrf {
 
 	/* Interfaces belonging to this VRF */
 	struct if_name_head ifaces_by_name;
+	struct if_index_head ifaces_by_index;
 
 	/* User data */
 	void *info;