rcutorture_one_extend
rcutorture_one_extend(readstate, mask, trsp, &rtrsp[j]);
rcutorture_one_extend(&rtorsp->readstate, 0, trsp, rtorsp->rtrsp);
rcutorture_one_extend(&rtorsp->readstate, 0, trsp, rtorsp->rtrsp);
rcutorture_one_extend(&rtors.readstate, newstate, trsp, rtors.rtrsp++);