Typically, the program takes care of that for you on the SCH E. I few years back I had a situation where I had paid off one of my three rentals. After that first full year with no mortgage interest deduction, the property actually showed a profit. That profit was offset "for me" by the program with accumulated losses on the other two properties. There was nothing to choose or select to make that happen. It just "happened".
If you'll take a look at the SCH E form, lines 24, 25 and 26 is where the math occurs that makes it happen.