ospfd: Optimize and improve SPF nexthop calculation
Maintain router LSA positions in OSPF interface.
Find the OSPF interface in nexthop_calculation using
the position in the router LSA. This is possible because
the only time nexthop_calculation needs to look up interfaces
is when dealing with its own Router LSA.
This has the following advantages:
- Multiple PtP interfaces with the same IP address between two routers.
- Use Unnumbered PtP on just one end of the link.
- Faster OI lookup for the OSPF interface and only
done once for PtoP links.
*ospf_interface.h: (struct ospf_interface) Add storage for
storing router LSA position.
*ospf_interface.c: (ospf_if_lookup_by_lsa_pos)
lookup OSPF I/F in an area using LSA position.
*ospf_lsa.c: (router_lsa_link_set) record Router LSA position.
*ospf_spf.c: (ospf_spf_next) Count and pass along lsa position.
(ospf_nexthop_calculation) Add lsa position argument.
call ospf_if_lookup_by_lsa_pos() for OSFP interface handle.
Clean up and remove all calls ospf_if_is_configured() the
rest. Adjust a few debug logs.
Signed-off-by: Joakim Tjernlund <Joakim.Tjernlund@transmode.se>
Signed-off-by: David Lamparter <equinox@opensourcerouting.org>
diff --git a/ospfd/ospf_interface.c b/ospfd/ospf_interface.c
index dc0787d..a37dde1 100644
--- a/ospfd/ospf_interface.c
+++ b/ospfd/ospf_interface.c
@@ -392,6 +392,21 @@
return NULL;
}
+/* Lookup OSPF interface by router LSA posistion */
+struct ospf_interface *
+ospf_if_lookup_by_lsa_pos (struct ospf_area *area, int lsa_pos)
+{
+ struct listnode *node;
+ struct ospf_interface *oi;
+
+ for (ALL_LIST_ELEMENTS_RO (area->oiflist, node, oi))
+ {
+ if (lsa_pos >= oi->lsa_pos_beg && lsa_pos < oi->lsa_pos_end)
+ return oi;
+ }
+ return NULL;
+}
+
struct ospf_interface *
ospf_if_lookup_by_local_addr (struct ospf *ospf,
struct interface *ifp, struct in_addr address)
@@ -801,6 +816,9 @@
return 0;
OSPF_ISM_EVENT_EXECUTE (oi, ISM_InterfaceDown);
+ /* delete position in router LSA */
+ oi->lsa_pos_beg = 0;
+ oi->lsa_pos_end = 0;
/* Shutdown packet reception and sending */
ospf_if_stream_unset (oi);