bridge: Remove unnecessary vlan_put_tag in br_handle_vlan (bdf4351b) · Commits · 戴 / test

br_handle_vlan() pushes HW accelerated vlan tag into skbuff when outgoing port is the bridge device. This is unnecessary because __netif_receive_skb_core() can handle skbs with HW accelerated vlan tag. In current implementation, __netif_receive_skb_core() needs to extract the vlan tag embedded in skb data. This could cause low network performance especially when receiving frames at a high frame rate on the bridge device. Signed-off-by:

Toshiaki Makita <makita.toshiaki@lab.ntt.co.jp> Acked-by:

Vlad Yasevich <vyasevic@redhat.com> Signed-off-by:

David S. Miller <davem@davemloft.net>

net/bridge/br_vlan.c

+0 −21

Original line number	Diff line number	Diff line
		@@ -151,27 +151,6 @@ struct sk_buff br_handle_vlan(struct net_bridge br,
		br_vlan_get_tag(skb, &vid);
		if (test_bit(vid, pv->untagged_bitmap))
		skb = br_vlan_untag(skb);
		else {
		/* Egress policy says "send tagged". If output device
		* is the bridge, we need to add the VLAN header
		* ourselves since we'll be going through the RX path.
		* Sending to ports puts the frame on the TX path and
		* we let dev_hard_start_xmit() add the header.
		*/
		if (skb->protocol != htons(ETH_P_8021Q) &&
		pv->port_idx == 0) {
		/* vlan_put_tag expects skb->data to point to
		* mac header.
		*/
		skb_push(skb, ETH_HLEN);
		skb = __vlan_put_tag(skb, skb->vlan_proto, skb->vlan_tci);
		if (!skb)
		goto out;
		/* put skb->data back to where it was */
		skb_pull(skb, ETH_HLEN);
		skb->vlan_tci = 0;
		}
		}

		out:
		return skb;

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