The Savage Attacker feat (PHB, p. 169) states:
Once per turn when you roll damage for a melee weapon attack, you can reroll the weapon’s damage dice and use either total.
Additionally, the rogue's Sneak Attack feature states:
Beginning at 1st level, you know how to strike subtly and exploit a foe’s distraction. Once per turn, you can deal an extra 1d6 damage to one creature you hit with an attack if you have advantage on the attack roll. The attack must use a finesse or a ranged weapon.
Considering that Sneak Attack damage deals the same kind of damage as the weapon, would Savage Attacker benefit it and let you reroll the Sneak Attack extra damage dice?