The implementation of network use two fundamental data structure socket buffer sk_buff and net_device.
sk_buff is where packets are stored and processed while net_device keep information about hardware device
and pointer to driver’s functions put data into sk_buff as well as get data from it.
Other important is softnet_data, which is per CPU and contain information needed for communication between
top half and bottom half
The softnet_data has the following noticeable fields
- poll_list is the list of devices that are polled because they have a nonempty receive queue
- output_queueis the list of devices that have something to transmit