On Wed, 29 Mar 2023 at 20:11, Kal Conley kal.conley@dectris.com wrote:

Fix flaky STATS_RX_DROPPED test. The receiver calls getsockopt after receiving the last (valid) packet which is not the final packet sent in the test (valid and invalid packets are sent in alternating fashion with the final packet being invalid). Since the last packet may or may not have been dropped already, both outcomes must be allowed.

This issue could also be fixed by making sure the last packet sent is valid. This alternative is left as an exercise to the reader (or the benevolent maintainers of this file).

This problem was quite visible on certain setups. On one machine this failure was observed 50% of the time.

Also, remove a redundant assignment of pkt_stream->nb_pkts. This field is already initialized by __pkt_stream_alloc.

This has been bugging me for a while so thanks for fixing this. Please break this commit out of this patch set and send it as a separate bug fix.

Acked-by: Magnus Karlsson magnus.karlsson@intel.com

Fixes: 27e934bec35b ("selftests: xsk: make stat tests not spin on getsockopt") Signed-off-by: Kal Conley kal.conley@dectris.com

---

tools/testing/selftests/bpf/xskxceiver.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/tools/testing/selftests/bpf/xskxceiver.c b/tools/testing/selftests/bpf/xskxceiver.c index 34a1f32fe752..1a4bdd5aa78c 100644 --- a/tools/testing/selftests/bpf/xskxceiver.c +++ b/tools/testing/selftests/bpf/xskxceiver.c @@ -633,7 +633,6 @@ static struct pkt_stream *pkt_stream_generate(struct xsk_umem_info *umem, u32 nb if (!pkt_stream) exit_with_error(ENOMEM);

•   pkt_stream->nb_pkts = nb_pkts;
    for (i = 0; i < nb_pkts; i++) {
            pkt_set(umem, &pkt_stream->pkts[i], (i % umem->num_frames) * umem->frame_size,
                    pkt_len);
  

@@ -1141,7 +1140,14 @@ static int validate_rx_dropped(struct ifobject *ifobject) if (err) return TEST_FAILURE;

•   if (stats.rx_dropped == ifobject->pkt_stream->nb_pkts / 2)
  

•   /* The receiver calls getsockopt after receiving the last (valid)
  

•    * packet which is not the final packet sent in this test (valid and
  

•    * invalid packets are sent in alternating fashion with the final
  

•    * packet being invalid). Since the last packet may or may not have
  

•    * been dropped already, both outcomes must be allowed.
  

•    */
  

•   if (stats.rx_dropped == ifobject->pkt_stream->nb_pkts / 2 ||
  

•       stats.rx_dropped == ifobject->pkt_stream->nb_pkts / 2 - 1)
            return TEST_PASS;
  
    return TEST_FAILURE;
  

-- 2.39.2