On Thu, Aug 5, 2021 at 3:43 PM Andrii Nakryiko
<andrii.nakryiko@xxxxxxxxx> wrote:
>
> On Sun, Jul 4, 2021 at 12:05 PM Cong Wang <xiyou.wangcong@xxxxxxxxx> wrote:
> >
> > From: Cong Wang <cong.wang@xxxxxxxxxxxxx>
> >
> > Add two test cases to ensure redirection between udp and unix
> > work bidirectionally.
> >
> > Cc: John Fastabend <john.fastabend@xxxxxxxxx>
> > Cc: Daniel Borkmann <daniel@xxxxxxxxxxxxx>
> > Cc: Jakub Sitnicki <jakub@xxxxxxxxxxxxxx>
> > Cc: Lorenz Bauer <lmb@xxxxxxxxxxxxxx>
> > Signed-off-by: Cong Wang <cong.wang@xxxxxxxxxxxxx>
> > ---
> > .../selftests/bpf/prog_tests/sockmap_listen.c | 170 ++++++++++++++++++
> > 1 file changed, 170 insertions(+)
> >
>
> [...]
>
> > + n = write(c1, "a", 1);
> > + if (n < 0)
> > + FAIL_ERRNO("%s: write", log_prefix);
> > + if (n == 0)
> > + FAIL("%s: incomplete write", log_prefix);
> > + if (n < 1)
> > + goto close;
> > +
> > + key = SK_PASS;
> > + err = xbpf_map_lookup_elem(verd_mapfd, &key, &pass);
> > + if (err)
> > + goto close;
> > + if (pass != 1)
> > + FAIL("%s: want pass count 1, have %d", log_prefix, pass);
> > +
> > + n = read(mode == REDIR_INGRESS ? p0 : c0, &b, 1);
> > + if (n < 0)
> > + FAIL_ERRNO("%s: read", log_prefix);
>
> Hey Cong,
>
> This test is pretty flaky and quite frequently fails in our CIs (e.g., [0]):
>
> ./test_progs-no_alu32:unix_udp_redir_to_connected:1949: egress: read:
> Resource temporarily unavailable
> unix_udp_redir_to_connected:FAIL:1949
>
> Please send a fix to make it more reliable. Thanks!
Using an unbound number of retries makes this reliable, but you
dislike it. ;) But, there must be some reason for the delay of
packet delivery, I guess it might be related to workqueue scheduling,
let me check it tomorrow.
Thanks.
