How to rte_epoll_wait for IPC?

[Morten Brørup]

Dear Harman, Anatoly and David,

I have been looking somewhat into power management, and have a question about rte_epoll:

Can I use rte_epoll to wait for an event (or interrupt/signal) in one EAL thread, generated by another EAL thread?

Here's a simple use case with two EAL threads:

1. The "ingress" thread receives its packets from the NICs, filters the packets and puts them into a an rte_ring for the "processing" thread. The "ingress" thread can sleep and use RX interrupts to wake up, as shown in the l3fwd-power example. All good.

2. The "processing" thread receives its packets from the rte_ring. This thread should sleep until packets are ready for it in the rte_ring.

The "ingress" thread knows when it puts packets into the rte_ring, so it can signal that event to the "processing" thread, to wake it up; either as an interrupt/signal, or through a file descriptor. Is this supported by rte_epoll (or other DPDK APIs), and how?


In a generic scenario, an EAL thread could be rte_epoll_wait'ing for a variety of event sources. This may require a different, more advanced, solution.

A solution to the simple use case suffices.


PS: I'm using the standard acronym IPC in the subject, although I'm asking about Inter Thread Communication, not Inter Process Communication. I'm not looking for a multi process solution.


Med venlig hilsen / Kind regards,
-Morten Brørup