J.K. Simmons is squarely in the middle of a muddled family in the dramady “Break Point.” His sons, played by Jeremy Sisto and David Walton, have been estranged for years, but decide to team up in order to compete in a tennis doubles championship. Dad’s not on the court, but he’s called in to referee, a lot. For the Oscar winner, part of the appeal was working with Sisto, with whom he shared a small screen on “Law and Order.” In this interview he talks about his role in “Break Point,” “Whiplash” and how the cream rises to the top.