nfsd has some cleanup that it wants to do when the last thread exits, and there will shortly be some more. So collect this all into one place and define a callback for an rpc service to call when the service is about to be destroyed. [akpm@osdl.org: cleanups, build fix] Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>