Soak wood chips in water at least 30 minutes.
Drain chips; place on a square of heavy-duty aluminum foil. Fold foil to seal; cut several slits in top of packet. Place foil packet on coals or lava rocks, and ignite. Let charcoal burn 30 minutes or a gas grill preheat over medium heat (300° to 350°) 15 minutes.
Brush cut sides of rolls with olive oil; sprinkle evenly with olives. Top with tomato slices and cheese and basil.
Coat food rack with cooking spray; place on grill. Place rolls, cut side up, on rack, and grill, covered with grill lid, 5 to 7 minutes or until cheese melts.
Note: Gruyère cheese is a Swiss-style cheese with a rich, sweet, nutty flavor.