In either case, once it has passed, resume paddling out. If your roll is completely reliable, and there are no rocks, you have the option of turning upside down and dragging deeper water with your paddle to avoid the wave's impact, but practice this with smaller waves first because of the unusual ways that the currents can pull on your arms - injury is possible. Also be aware of the fact that the first exposure of the eyes to saltwater when rolling can be very distracting. As opposed the the deliberate gunwale lifting while surfing, when out in the swells it is important to have very relaxed and loose hips. Be flexible as the waves pass underneath you.
Waves can and do collapse and explode unpredictably, and staying loose is a big help.
Use short strokes with a lot of quick braces thrown in. Paddling with dolphins is fun, but if you see two pods meeting clear out fast. First analyze the waves. Are they dumping, spilling, or surging. If they just lose energy as they wash up on the beach, no problem.