Once you build your Graph there are algorithms to return all paths https://metacpan.org/dist/Graph/view/lib/Graph.pod#All-Pairs-Shortest-Paths-(APSP) (see https://metacpan.org/dist/Graph/view/lib/Graph.pod#all_paths therein). If standard algorithms exist for what you want to do then they will most-likely beat any low-level DIY algorithms. So, use Graph algorithms if you have a Graph.

Also, links can be resolved at construction time with, say, https://metacpan.org/pod/Cwd#abs_path-and-friends or readlink. Caveat: querying the filesystem with said functions will be slower than your methods I guess. But it will be safer.

bw, bliako