From 57b5860f013953ce161d05302e05370db9cd6ee2 Mon Sep 17 00:00:00 2001 From: Neale Ranns Date: Sat, 15 Jul 2017 07:37:25 -0700 Subject: FIB path preference Paths are given a preference, lowest value is 'best'. Only paths that are up are up contribute to fprwarding - that's unchanged. What's new is that of the path's that re up only those that have the best preference contribute. A poor man's primary and backup. It's not true primary/backup function because the FIB must converge before the lower preference paths are used. Change-Id: Ie4453c4a7b1094c6c2b51fe1594b8302103bb68e Signed-off-by: Neale Ranns --- src/vnet/fib/fib_entry_src.c | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) (limited to 'src/vnet/fib/fib_entry_src.c') diff --git a/src/vnet/fib/fib_entry_src.c b/src/vnet/fib/fib_entry_src.c index 8c5082846a8..ff73cbf90f1 100644 --- a/src/vnet/fib/fib_entry_src.c +++ b/src/vnet/fib/fib_entry_src.c @@ -193,6 +193,7 @@ typedef struct fib_entry_src_collect_forwarding_ctx_t_ const fib_entry_src_t *esrc; fib_forward_chain_type_t fct; int n_recursive_constrained; + u16 preference; } fib_entry_src_collect_forwarding_ctx_t; /** @@ -351,6 +352,22 @@ fib_entry_src_collect_forwarding (fib_node_index_t pl_index, { ctx->n_recursive_constrained += 1; } + if (0xffff == ctx->preference) + { + /* + * not set a preference yet, so the first path we encounter + * sets the preference we are collecting. + */ + ctx->preference = fib_path_get_preference(path_index); + } + else if (ctx->preference != fib_path_get_preference(path_index)) + { + /* + * this path does not belong to the same preference as the + * previous paths encountered. we are done now. + */ + return (FIB_PATH_LIST_WALK_STOP); + } /* * get the matching path-extension for the path being visited. @@ -422,6 +439,7 @@ fib_entry_src_mk_lb (fib_entry_t *fib_entry, .next_hops = NULL, .n_recursive_constrained = 0, .fct = fct, + .preference = 0xffff, }; /* -- cgit 1.2.3-korg