[PATCH net-next 4/4] wireguard: device: support big tcp GSO

["Jason A. Donenfeld" <Jason@zx2c4.com>]

From: Daniel Borkmann <daniel@iogearbox.net>

Advertise GSO_MAX_SIZE as TSO max size in order support BIG TCP for wireguard.
This helps to improve wireguard performance a bit when enabled as it allows
wireguard to aggregate larger skbs in wg_packet_consume_data_done() via
napi_gro_receive(), but also allows the stack to build larger skbs on xmit
where the driver then segments them before encryption inside wg_xmit().
We've seen a 15% improvement in TCP stream performance.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
---
 drivers/net/wireguard/device.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/net/wireguard/device.c b/drivers/net/wireguard/device.c
index a2ba71fbbed4..6cf173a008e7 100644
--- a/drivers/net/wireguard/device.c
+++ b/drivers/net/wireguard/device.c
@@ -302,6 +302,8 @@ static void wg_setup(struct net_device *dev)
 	/* We need to keep the dst around in case of icmp replies. */
 	netif_keep_dst(dev);
 
+	netif_set_tso_max_size(dev, GSO_MAX_SIZE);
+
 	wg->dev = dev;
 }
 
-- 
2.46.0