> From: Honnappa Nagarahalli [mailto:[email protected]] > Sent: Friday, 6 October 2023 17.27 > > > From: Morten Brørup <[email protected]> > > Sent: Friday, October 6, 2023 5:04 AM > > > > 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? > This feature is supported by using rte_wait_until_equal_xx APIs in > rte_ring.
Thank you for the suggestion, Honnappa. rte_wait_until_equal_xx would be an excellent solution for physical appliances. However, I am looking for O/S level sleeping, like epoll(), so the hypervisor can detect that the thread is idle. (I should have mentioned this!) > > > > > > > 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
