Re: [dpdk-dev] [RFC] service: stop lcore threads before 'finalize'

[David Marchand <david.marchand@redhat.com>]

On Fri, Jan 17, 2020 at 9:17 AM David Marchand
<david.marchand@redhat.com> wrote:
>
> On Thu, Jan 16, 2020 at 8:50 PM Aaron Conole <aconole@redhat.com> wrote:
> >
> > I've noticed an occasional segfault from the build system in the
> > service_autotest and after talking with David (CC'd), it seems like it's
> > due to the rte_service_finalize deleting the lcore_states object while
> > active lcores are running.
> >
> > The below patch is an attempt to solve it by first reassigning all the
> > lcores back to ROLE_RTE before releasing the memory.  There is probably
> > a larger question for DPDK proper about actually closing the pending
> > lcore threads, but that's a separate issue.  I've been running with the
> > patch for a while, and haven't seen the crash anymore on my system.
> >
> > Thoughts?  Is it acceptable as-is?
>
> Added this patch to my env, still reproducing the same issue after ~10-20 tries.
> I added a breakpoint to service_lcore_uninit that is indeed caught
> when exiting the test application (just wanted to make sure your
> change was in my binary).

Harry,

We need a fix for this issue.

Interestingly, Stephen patch that joins all pthreads at
rte_eal_cleanup [1] makes this issue disappear.
So my understanding is that we are missing a api (well, I could not
find a way) to synchronously stop service lcores.


1: https://patchwork.dpdk.org/patch/64201/

-- 
David Marchand