xxxxxx

void _timerwheel_tick(timerwheel_t *tw) {
    ++tw->currtick;

    uint32_t currtick = tw->currtick;
    int index = (currtick & TVR_MASK); 
    if (index == 0) {
        int i = 0;
        int idx;
        do {
            idx = NTH_INDEX(tw->currtick, i);
            _timerwheel_cascade(tw, &(tw->tv[i]), idx);
        } while (idx == 0 && ++i < 4);
    }
}