Name of song w/Eminem in it.?

Not sure if it's an eminem song or he performs on another track. The part of the song I remember is when he talks about the order of rap superstars and where he lies in the group, He's like "biggie is #1, jay-z #2, nas #3 and I'm #4. Then he says something about I know when my time is done and i bow out..etc.. Not much to go on but I hope some fellow Eminem fan can chime in on this. Thanks much!!