Roughing is to harass someone.
Roughing someone up can also be used in a friendly manner such as when you: "Give someone a hard time."
Can include physical contact or simply verbal insults.
Person Two and Three: "We're just roughing you up! Just giving you a hard time!"
Person One: "Whatever"
Person One: "Just go away!"
Person Two and Three: "Awww poor baby can't handle it?"