MLX4_EN_XDP_TX_NRTXBB
#define MLX4_EN_XDP_TX_REAL_SZ (((CTRL_SIZE + MLX4_EN_XDP_TX_NRTXBB * DS_SIZE) \
tx_info->nr_txbb = MLX4_EN_XDP_TX_NRTXBB;
WRITE_ONCE(ring->prod, ring->prod + MLX4_EN_XDP_TX_NRTXBB);