Hey everyone well my question is this how can you tell if your car has bad piston rings or if the valve seals are bad??

-My car drives normal and fine but when I push the car passing 6 RPM's it smokes a lot (white smoke) and does it for like a 30 seconds but then stops smoking. Once again it only smokes when I push the car at high RPM's, IDK if its the valve seals or piston rings. Please let me know what you think or what the difference would be on how to tell which one is bad thanks.