[PATCH net] selftests: net: give more time for GRO aggregation

From: Paolo Abeni <pabeni@redhat.com>
To: netdev@vger.kernel.org
Cc: "David S. Miller" <davem@davemloft.net>,
	Eric Dumazet <edumazet@google.com>,
	Jakub Kicinski <kuba@kernel.org>, Shuah Khan <shuah@kernel.org>,
	linux-kselftest@vger.kernel.org
Subject: [PATCH net] selftests: net: give more time for GRO aggregation
Date: Thu, 25 Jan 2024 19:09:06 +0100	[thread overview]
Message-ID: <bffec2beab3a5672dd13ecabe4fad81d2155b367.1706206101.git.pabeni@redhat.com> (raw)

The gro.sh test-case relay on the gro_flush_timeout to ensure
that all the segments belonging to any given batch are properly
aggregated.

The other end, the sender is a user-space program transmitting
each packet with a separate write syscall. A busy host and/or
stracing the sender program can make the relevant segments reach
the GRO engine after the flush timeout triggers.

Give the GRO flush timeout more slack, to avoid sporadic self-tests
failures.

Fixes: 9af771d2ec04 ("selftests/net: allow GRO coalesce test on veth")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
---
 tools/testing/selftests/net/setup_veth.sh | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/testing/selftests/net/setup_veth.sh b/tools/testing/selftests/net/setup_veth.sh
index a9a1759e035c..1f78a87f6f37 100644
--- a/tools/testing/selftests/net/setup_veth.sh
+++ b/tools/testing/selftests/net/setup_veth.sh
@@ -11,7 +11,7 @@ setup_veth_ns() {
 	local -r ns_mac="$4"
 
 	[[ -e /var/run/netns/"${ns_name}" ]] || ip netns add "${ns_name}"
-	echo 100000 > "/sys/class/net/${ns_dev}/gro_flush_timeout"
+	echo 1000000 > "/sys/class/net/${ns_dev}/gro_flush_timeout"
 	ip link set dev "${ns_dev}" netns "${ns_name}" mtu 65535
 	ip -netns "${ns_name}" link set dev "${ns_dev}" up
 
-- 
2.43.0

