From 215eb9f962091ebaab96be2c18cf5d0f5174a4d6 Mon Sep 17 00:00:00 2001 From: Liang Chen Date: Thu, 24 Aug 2023 20:31:31 +0800 Subject: [PATCH] veth: Avoid NAPI scheduling on failed SKB forwarding When an skb fails to be forwarded to the peer(e.g., skb data buffer length exceeds MTU), it will not be added to the peer's receive queue. Therefore, we should schedule the peer's NAPI poll function only when skb forwarding is successful to avoid unnecessary overhead. Signed-off-by: Liang Chen Link: https://lore.kernel.org/r/20230824123131.7673-1-liangchen.linux@gmail.com Signed-off-by: Jakub Kicinski --- drivers/net/veth.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) diff --git a/drivers/net/veth.c b/drivers/net/veth.c index da44bb1331ffb..d43e62ebc2fcd 100644 --- a/drivers/net/veth.c +++ b/drivers/net/veth.c @@ -373,14 +373,13 @@ static netdev_tx_t veth_xmit(struct sk_buff *skb, struct net_device *dev) if (likely(veth_forward_skb(rcv, skb, rq, use_napi) == NET_RX_SUCCESS)) { if (!use_napi) dev_lstats_add(dev, length); + else + __veth_xdp_flush(rq); } else { drop: atomic64_inc(&priv->dropped); } - if (use_napi) - __veth_xdp_flush(rq); - rcu_read_unlock(); return NETDEV_TX_OK; -- 2.30.2