From: Hariprasad Shenai hariprasad@chelsio.com
commit 8d09e6b8b9c9969ac59496dc21e10b67fe727e7e upstream.
The commit 637d3e997351 ("cxgb4: Discard the packet if the length is greater than mtu") introduced a regression in the VLAN interface performance when Tx VLAN offload is disabled.
Check if skb is tagged, regardless of whether it is hardware accelerated or not. Presently we were checking only for hardware acclereated one, which caused performance to drop to ~0.17Mbps on a 10GbE adapter for VLAN interface, when tx vlan offload is turned off using ethtool. The ethernet head length calculation was going wrong in this case, and driver ended up dropping packets.
Fixes: 637d3e997351 ("cxgb4: Discard the packet if the length is greater than mtu") Signed-off-by: Hariprasad Shenai hariprasad@chelsio.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/net/ethernet/chelsio/cxgb4/sge.c | 2 +- drivers/net/ethernet/chelsio/cxgb4vf/sge.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-)
--- a/drivers/net/ethernet/chelsio/cxgb4/sge.c +++ b/drivers/net/ethernet/chelsio/cxgb4/sge.c @@ -1165,7 +1165,7 @@ out_free: dev_kfree_skb_any(skb);
/* Discard the packet if the length is greater than mtu */ max_pkt_len = ETH_HLEN + dev->mtu; - if (skb_vlan_tag_present(skb)) + if (skb_vlan_tagged(skb)) max_pkt_len += VLAN_HLEN; if (!skb_shinfo(skb)->gso_size && (unlikely(skb->len > max_pkt_len))) goto out_free; --- a/drivers/net/ethernet/chelsio/cxgb4vf/sge.c +++ b/drivers/net/ethernet/chelsio/cxgb4vf/sge.c @@ -1188,7 +1188,7 @@ int t4vf_eth_xmit(struct sk_buff *skb, s
/* Discard the packet if the length is greater than mtu */ max_pkt_len = ETH_HLEN + dev->mtu; - if (skb_vlan_tag_present(skb)) + if (skb_vlan_tagged(skb)) max_pkt_len += VLAN_HLEN; if (!skb_shinfo(skb)->gso_size && (unlikely(skb->len > max_pkt_len))) goto out_free;