netif_rx    // 网卡驱动里面调用这个函数上传skb
  netif_rx_internal 
    do_xdp_generic    // xdp的处理
      netif_receive_generic_xdp
    get_rps_cpu       // rps的cpu调度
      u16 index = skb_get_rx_queue(skb);
      flow_table = rcu_dereference(rxqueue->rps_flow_table);
      sock_flow_table = rcu_dereference(rps_sock_flow_table);
      rflow = &flow_table->flows[hash & flow_table->mask];
      rflow = set_rps_cpu(dev, skb, rflow, next_cpu);
    enqueue_to_backlog  // 添加skb到cpu的backoog队列
      ____napi_schedule(sd, &sd->backlog);
        __raise_softirq_irqoff(NET_RX_SOFTIRQ); 


net_rx_action   // 软中断NET_RX_SOFTIRQ处理函数
  napi_poll
    process_backlog

process_backlog
  __netif_receive_skb
    __netif_receive_skb_one_core
      __netif_receive_skb_core

napi_complete_done
  ____napi_schedule
    __raise_softirq_irqoff(NET_RX_SOFTIRQ);


dev_queue_xmit
__dev_queue_xmit
  dev_hard_start_xmit
    xmit_one
      netdev_start_xmit
        ops->ndo_start_xmit(skb, dev);

netif_schedule_queue
netif_tx_wake_queue
__netif_schedule
  net_tx_action
    qdisc_run(q);
      qdisc_restart
        txq = skb_get_tx_queue(dev, skb);
        sch_direct_xmit
          dev_hard_start_xmit
      __netif_schedule(q);