title: Understanding of "process_queue" and "input_pkt_queue" in network driver layer
body: <p>Network driver enqueues the incoming data to "input_pkt_queue" in enqueue_to_backlog() API.</p>
  
  <p>process_backlog()(which is called in softirq context), is where these packets are processed. In process_backlog() API, first packets from "input_pkt_queue" are moved to "process_queue". And from "process_queue" packets are sent to TCP/IP stack.</p>
  
  <p>Is there any reason why "process_queue" is used in between? </p>