Technically, you could consider drums a "percussive" instrument, but in common use the term percussion usually refers to instruments that are rhythm-based, but not your traditional "drums." The main "drums" in a drum set are snares, toms, a bass drum and cymbals. Commonly instruments like shakers, woodblocks, triangles (and even other types of drums like tablas, dhols, hand drums, etc) are called "percussion" instruments.