Linux下ovs bridge等如何收从内核接管报文处理

参考Linux内核收包流程，函数调用链是：
硬件中断 -->do_IRQ–>handle_irq–>e1000_intr_msix_rx–>__napi_schedule(&adapter->napi)–>

____napi_schedule–>__raise_softirq_irqoff(NET_RX_SOFTIRQ)

do_IRQ–>irq_exit–>do_softirq–>call_softirq–>__do_softirq–>

net_rx_action->e1000e_poll–>e1000_receive_skb->napi_gro_receive–>

netif_receive_skb–>__netif_receive_skb–>__netif_receive_skb_core–>

deliver_skb–>ip_rcv–>NF_HOOK(NF_INET_PRE_ROUTING)–>

ip_rcv_finish–>dst_input–>ip_local_deliver–>

NF_HOOK(NF_INET_LOCAL_IN)–>ip_local_deliver_finish–>ipprot->handler()
如果ovs 或者普通的网桥如何报文在哪里接收呢？通过梳理代码发现上述调用流程中的__netif_receive_skb_core函数有个rx_handler，ovs bridge等都是通过设置该函数指针实现对报文的接管。

内核版本4.4
    __netif_receive_skb_core函数中如下片段
    rx_handler = rcu_dereference(skb->dev-