Re: [PATCH bpf-next] tools/testing/selftests/bpf/test_tc_tunnel.sh: Fix wait for server bind

[Stanislav Fomichev <stfomichev@gmail.com>]

On 12/03, Marco Leogrande wrote:
> On Mon, Dec 2, 2024 at 4:15 PM Stanislav Fomichev <stfomichev@gmail.com> wrote:
> > Do you see this failing in your CI or in the BPF CI?
> 
> I see this failing in our internal CI, in around 1% to 2% of the CI runs.
> 
> > It seems ok
> > to add wait_for_port here, but the likelihood of the issue seems
> > minuscule. There is a bunch of ip/tc/etc calls between this
> > server_listen and the next client_connect (and I'd be surprised to hear
> > that netcat is still not listening by the time we reach next
> > client_connect).
> 
> I'm surprised as well, and I've not found a good correlation with the
> root cause of the delayed server start, besides generic "slowness".
> 
> You also make a good point - by calling wait_for_port this early we
> "waste" the opportunity to run the other ip commands in parallel in
> the meantime.
> I had considered moving this wait down, just before the next
> client_connect, but I concluded it might be less readable since it
> would be so distant from the server_listen it pairs with. But I can
> make that change if it seems better.

Thanks for the details, let's keep as is.

Acked-by: Stanislav Fomichev <sdf@fomichev.me>