about netmap NETMAP_HW_RING recv pcaket

in pkt-gen.c 
tifreq.nr_ringid = (g.nthreads > 1) ? (i | NETMAP_HW_RING) : 0; 

in netmap.c 
if (priv->np_qlast != NETMAP_HW_RING) {
lim_tx = lim_rx = priv->np_qlast;
}
....

if nthreads 2.but have 8 num_tx_rings.(ixgbe default is 8)
looks like
thread #1 priv->np_qfirst = 0 priv->np_qlast = 1 
thread #2 priv->np_qfirst = 1 priv->np_qlast = 2
 
if packet in  num_tx_rings 2-7 will be lost some packet?