Truthfully? Nothing. Perjury is a criminal matter, and it is exceedingly rare to see anyone actually prosecuted for it. You could have impeached his testimony with evidence he was lying, but it sounds like that didn't happen.
If you believe the lie affected the court's decision, you could file a motion for a new trial, but these are rarely granted. You would need to demonstrate that you have new evidence - which means evidence you could not have obtained before the original trial.