For clarification of my earlier post:
The race condition concerns tx_buf in lib/openflow.cc. If
Openflow_connection::send_packet() is called by one thread at a time, tx_buf is
always checked (via tx_buf.get()) to see if it's empty before it's sent, after
which it's cleared (tx_buf.reset()).
I think this is a race condition because you're calling send_openflow_packet()
from a non-cooperative thread.
I think your best bet is probably to rewrite your server thread as a
cooperative thread.
There are other options... you could have queue which is consumed by a simple
cooperative
