[PATCH net v2] selftests: net: cope with slow env in gro.sh test

[PATCH net v2] selftests: net: cope with slow env in gro.sh test

[Paolo Abeni]

The gro self-tests sends the packets to be aggregated with
multiple write operations.

When running is slow environment, it's hard to guarantee that
the GRO engine will wait for the last packet in an intended
train.

The above causes almost deterministic failures in our CI for
the 'large' test-case.

Address the issue explicitly ignoring failures for such case
in slow environments (KSFT_MACHINE_SLOW==true).

Fixes: 7d1575014a63 ("selftests/net: GRO coalesce test")
Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
---
v1 -> v2:
  - replace the '-a' operator with '&&' - Mattbe

Note that the fixes tag is there mainly to justify targeting the net
tree, and this is aiming at net to hopefully make the test more stable
ASAP for both trees.

I experimented with a largish refactory replacing the multiple writes
with a single GSO packet, but exhausted by time budget before reaching
any good result.
---
 tools/testing/selftests/net/gro.sh | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/tools/testing/selftests/net/gro.sh b/tools/testing/selftests/net/gro.sh
index 19352f106c1d..3190b41e8bfc 100755
--- a/tools/testing/selftests/net/gro.sh
+++ b/tools/testing/selftests/net/gro.sh
@@ -31,6 +31,10 @@ run_test() {
       1>>log.txt
     wait "${server_pid}"
     exit_code=$?
+    if [[ ${test} == "large" && -n "${KSFT_MACHINE_SLOW}" ]]; then
+        echo "Ignoring errors due to slow environment" 1>&2
+        exit_code=0
+    fi
     if [[ "${exit_code}" -eq 0 ]]; then
         break;
     fi
-- 
2.43.0

Re: [PATCH net v2] selftests: net: cope with slow env in gro.sh test

[Matthieu Baerts]

Hi Paolo,

On 07/02/2024 19:36, Paolo Abeni wrote:
> The gro self-tests sends the packets to be aggregated with
> multiple write operations.
> 
> When running is slow environment, it's hard to guarantee that
> the GRO engine will wait for the last packet in an intended
> train.
> 
> The above causes almost deterministic failures in our CI for
> the 'large' test-case.
> 
> Address the issue explicitly ignoring failures for such case
> in slow environments (KSFT_MACHINE_SLOW==true).
> 
> Fixes: 7d1575014a63 ("selftests/net: GRO coalesce test")
> Reviewed-by: Willem de Bruijn <willemb@google.com>
> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
> ---
> v1 -> v2:
>   - replace the '-a' operator with '&&' - Mattbe

Thank you for the v2!

Reviewed-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>

Cheers,
Matt
-- 
Sponsored by the NGI0 Core fund.

Re: [PATCH net v2] selftests: net: cope with slow env in gro.sh test

[Jakub Kicinski]

On Wed,  7 Feb 2024 19:36:46 +0100 Paolo Abeni wrote:
> +    if [[ ${test} == "large" && -n "${KSFT_MACHINE_SLOW}" ]]; then
> +        echo "Ignoring errors due to slow environment" 1>&2
> +        exit_code=0
> +    fi

Would it make sense to also add "&& $exit_code -ne 0" ?
It may be useful to see in logs how many times we actually
ignored the error?

Re: [PATCH net v2] selftests: net: cope with slow env in gro.sh test

[Paolo Abeni]

On Fri, 2024-02-09 at 11:15 -0800, Jakub Kicinski wrote:
> On Wed,  7 Feb 2024 19:36:46 +0100 Paolo Abeni wrote:
> > +    if [[ ${test} == "large" && -n "${KSFT_MACHINE_SLOW}" ]]; then
> > +        echo "Ignoring errors due to slow environment" 1>&2
> > +        exit_code=0
> > +    fi
> 
> Would it make sense to also add "&& $exit_code -ne 0" ?
> It may be useful to see in logs how many times we actually
> ignored the error?

Yep, I'll send a v3.

Thanks!

Paolo