Hi, I want to improve my understanding about the logic of the code written for 'process_backlog ()' . File Source: net/core/dev.c, linux-2.6.16 I am considering only Non-NAPI network devices ( > 1) in this discussion. The 'net_rx_action' function invokes 'dev->poll(dev, &budget)' for each network device present in 'poll_list'. ' The default handler for Non-NAPI network devices is 'process_backlog ()'. The signature of the function is: static int process_backlog (struct net_device *backlog_dev, int *budget) 'backlog_dev' represents the device for which the 'poll' function is invoked. In the code body the function acts on CPU specific 'input_pkt_queue'. This queue holds all the incoming packets from the network devices and 'poll_list' has reference for these network devices. The function takes out one element (packet) from the 'input_pkt_queue' and process the packet. As the 'input_pkt_queue' is shared by all the network devices, the 'packet' which is popped-out from the list can be from any network device not required to be from 'backlog_dev' (the device for which 'process_backlog' has been called). I have confusion here. The code doesn't operate only on the packets queued-in by 'backlog_dev' to 'input_pkt_queue'. It pops-out the node from the queue and process it. But it updates the 'quota' which is specific for the device 'backlog_dev' for which the function have got called. Why it is so? Am I missing out something here? Thanks for reading my mail patiently. Regards, Sachin Rane _______________________________________________ Kernelnewbies mailing list Kernelnewbies@xxxxxxxxxxxxxxxxx http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
