From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andrew Gallatin Subject: [PATCH v2 net-next 2/3] myri10ge: Add vlan rx for better GRO perf. Date: Wed, 14 Nov 2012 11:32:29 -0500 Message-ID: <50A3C79D.8010400@myri.com> References: <50A3975B.7020608@myri.com> <1352904408.4497.11.camel@edumazet-glaptop> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Cc: Eric Dumazet To: netdev Return-path: Received: from mail-gg0-f174.google.com ([209.85.161.174]:59537 "EHLO mail-gg0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932664Ab2KNQcc (ORCPT ); Wed, 14 Nov 2012 11:32:32 -0500 Received: by mail-gg0-f174.google.com with SMTP id k2so112783ggd.19 for ; Wed, 14 Nov 2012 08:32:32 -0800 (PST) In-Reply-To: <1352904408.4497.11.camel@edumazet-glaptop> Sender: netdev-owner@vger.kernel.org List-ID: Unlike LRO, GRO requires that vlan tags be removed before aggregation can occur. Since the myri10ge NIC does not support hardware vlan tag offload, we must remove the tag in the driver to achieve performance comparable to LRO for vlan tagged frames. Updated with change suggested by Eric Duzamet to simplify the vlan tag popping & a change by me to always pop tags when NETIF_F_HW_VLAN_RX is set. Signed-off-by: Andrew Gallatin --- drivers/net/ethernet/myricom/myri10ge/myri10ge.c | 40 ++++++++++++++++++++++ 1 file changed, 40 insertions(+) diff --git a/drivers/net/ethernet/myricom/myri10ge/myri10ge.c b/drivers/net/ethernet/myricom/myri10ge/myri10ge.c index a5ab2f2..93ed089 100644 --- a/drivers/net/ethernet/myricom/myri10ge/myri10ge.c +++ b/drivers/net/ethernet/myricom/myri10ge/myri10ge.c @@ -1264,6 +1264,41 @@ myri10ge_unmap_rx_page(struct pci_dev *pdev, } } +/* + * GRO does not support acceleration of tagged vlan frames, and + * this NIC does not support vlan tag offload, so we must pop + * the tag ourselves to be able to achieve GRO performance that + * is comparable to LRO. + */ + +static inline void +myri10ge_vlan_rx(struct net_device *dev, void *addr, struct sk_buff *skb) +{ + u8 *va; + struct vlan_ethhdr *veh; + struct skb_frag_struct *frag; + + va = addr; + va += MXGEFW_PAD; + veh = (struct vlan_ethhdr *) va; + if ((dev->features & (NETIF_F_HW_VLAN_RX)) == NETIF_F_HW_VLAN_RX && + (veh->h_vlan_proto == ntohs(ETH_P_8021Q))) { + /* fixup csum if needed */ + if (skb->ip_summed == CHECKSUM_COMPLETE) + skb->csum = csum_sub(skb->csum, + csum_partial(va + ETH_HLEN, + VLAN_HLEN, 0)); + /* pop tag */ + __vlan_hwaccel_put_tag(skb, ntohs(veh->h_vlan_TCI)); + memmove(va + VLAN_HLEN, va, 2 * ETH_ALEN); + skb->len -= VLAN_HLEN; + skb->data_len -= VLAN_HLEN; + frag = skb_shinfo(skb)->frags; + frag->page_offset += VLAN_HLEN; + skb_frag_size_set(frag, skb_frag_size(frag) - VLAN_HLEN); + } +} + static inline int myri10ge_rx_done(struct myri10ge_slice_state *ss, int len, __wsum csum) { @@ -1329,6 +1364,7 @@ myri10ge_rx_done(struct myri10ge_slice_state *ss, int len, __wsum csum) skb->ip_summed = CHECKSUM_COMPLETE; skb->csum = csum; } + myri10ge_vlan_rx(mgp->dev, va, skb); skb_record_rx_queue(skb, ss - &mgp->ss[0]); napi_gro_frags(&ss->napi); @@ -3854,6 +3890,10 @@ static int myri10ge_probe(struct pci_dev *pdev, const struct pci_device_id *ent) netdev->netdev_ops = &myri10ge_netdev_ops; netdev->mtu = myri10ge_initial_mtu; netdev->hw_features = mgp->features | NETIF_F_RXCSUM; + + /* fake NETIF_F_HW_VLAN_RX for good GRO performance */ + netdev->hw_features |= NETIF_F_HW_VLAN_RX; + netdev->features = netdev->hw_features; if (dac_enabled) -- 1.7.9.5