fib_find_node
l = fib_find_node(t, &tp, be32_to_cpu(fri->dst));
l = fib_find_node(t, &tp, key);
l = l ? l : fib_find_node(t, &tp, key);
l = fib_find_node(t, &tp, key);
local_l = fib_find_node(lt, &local_tp, l->key);