IGB_RING_FLAG_TX_DETECT_HANG
set_bit(IGB_RING_FLAG_TX_DETECT_HANG, &tx_ring->flags);
if (test_bit(IGB_RING_FLAG_TX_DETECT_HANG, &tx_ring->flags)) {
clear_bit(IGB_RING_FLAG_TX_DETECT_HANG, &tx_ring->flags);