-----Original Message----- > Date: Mon, 30 Jul 2018 09:17:47 +0000 > From: "Elo, Matias (Nokia - FI/Espoo)" <matias....@nokia.com> > To: Jerin Jacob <jerin.ja...@caviumnetworks.com> > CC: "dev@dpdk.org" <dev@dpdk.org>, "Van Haaren, Harry" > <harry.van.haa...@intel.com> > Subject: Re: [dpdk-dev] eventdev: method for finding out unlink status > x-mailer: Apple Mail (2.3445.9.1) > > > >> > >> In bug report https://bugs.dpdk.org/show_bug.cgi?id=60 we have been > >> discussing > >> issues related to events ending up in wrong ports after calling > >> rte_event_port_unlink(). In addition of finding few bugs we have > >> identified a > >> need for a new API call (or documentation extension) for an application to > >> be > > > > From HW perspective, documentation extension should be enough. adding > > "there may be pre-scheduled events and the application is responsible to > > process them" > > on unlink(). Since dequeue() has which queue it is dequeue-ed from, the > > application can allays make action based on that(i.e, Is the event > > post/pre to unlink) > > At least in case of SW eventdev the problem is how the application can know > that > it has processed all pre-scheduled events. E.g. dequeue may return nothing > but since > the scheduler is running as a separate process events may still end up to the > unlinked > port asynchronously.
Can't we do, dequeue() in loop to get all the events from port. If dequeue returns with zero event then ports are drained up. Right? > > > > >> able to find out when an unlink() call has finished and no new events are > >> scheduled anymore to the particular event port. This is required e.g. when > >> doing > >> clean-up after an application thread stops processing events. > > > > If thread stopping then it better to call dev_stop(). At least in HW > > implementation, > > For an application doing dynamic load balancing stopping the whole eventdev > is not an > option. OK. Makes sense. Doing unlink() and link() in fastpath is not a problem. Changing core assignment to event port is problem without stop(). I guess, you application or general would be OK with that constraint. > > > A given event port assigned to a new lcore other than > > it previous one then we need to do some clean up at port level. > > In my case I'm mapping an event port per thread statically (basically > thread_id == port_id), > so this shouldn't be an issue. > >
