* port 0 receive and forward to port 1, the same to port 1, these 2 ports will have
* dependency. If one port stopped working (killed, for example), the port need to
* be stopped/started again. During the time, another port need to wait until stop/start
* procedure completed. So, record the pair relationship for those lcores working
* port 0 receive and forward to port 1, the same to port 1, these 2 ports will have
* dependency. If one port stopped working (killed, for example), the port need to
* be stopped/started again. During the time, another port need to wait until stop/start
* procedure completed. So, record the pair relationship for those lcores working