add comment about eliding the lock on addrs read
@@ -136,7 +136,9 @@ again:
ar.mx.Unlock()
// this dance is necessary to cover the Private->Public->Private transition
// where we were already connected to enough relays while private and dropped
- // the addrs while public
+ // the addrs while public.
+ // Note tht we don't need the lock for reading addrs, as the only writer is
+ // the current goroutine.
if ar.addrs == nil {
ar.updateAddrs()
}
