[PATCH] selftests/net: give more time to udpgro nat tests

[Lucas Karpinski]

In some conditions, background processes in udpgro don't have enough
time to set up the sockets. When foreground processes start, this
results in the bad GRO lookup test freezing or reporting that it
received 0 gro segments.

To fix this, increase the time given to background processes to complete
the startup before foreground processes start.

This is the same issue and the same fix as posted by Adrien Therry.
Link: https://lore.kernel.org/all/20221101184809.50013-1-athierry@xxxxxxxxxx/

Signed-off-by: Lucas Karpinski <lkarpins@xxxxxxxxxx>
---
 tools/testing/selftests/net/udpgro.sh | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/tools/testing/selftests/net/udpgro.sh b/tools/testing/selftests/net/udpgro.sh
index 0c743752669a..4ccbcb2390ad 100755
--- a/tools/testing/selftests/net/udpgro.sh
+++ b/tools/testing/selftests/net/udpgro.sh
@@ -97,7 +97,8 @@ run_one_nat() {
 		echo "ok" || \
 		echo "failed"&
 
-	sleep 0.1
+	# Hack: let bg programs complete the startup
+	sleep 0.2
 	./udpgso_bench_tx ${tx_args}
 	ret=$?
 	kill -INT $pid
-- 
2.41.0