From 1b4c44e6369dbbafd113f1e00b406f1eda5ab5b2 Mon Sep 17 00:00:00 2001 From: Andrew Gallatin Date: Fri, 30 Nov 2012 08:31:59 +0000 Subject: [PATCH] myri10ge: Add vlan rx for better GRO perf. 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. Thanks to Eric Duzamet for his help simplifying the original patch. Signed-off-by: Andrew Gallatin Signed-off-by: David S. Miller --- drivers/net/ethernet/myricom/myri10ge/myri10ge.c | 41 ++++++++++++++++++++++++ 1 file changed, 41 insertions(+) diff --git a/drivers/net/ethernet/myricom/myri10ge/myri10ge.c b/drivers/net/ethernet/myricom/myri10ge/myri10ge.c index 84207c0..2fc984a 100644 --- a/drivers/net/ethernet/myricom/myri10ge/myri10ge.c +++ b/drivers/net/ethernet/myricom/myri10ge/myri10ge.c @@ -1264,6 +1264,42 @@ 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; + __wsum vsum; + + 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) { + vsum = csum_partial(va + ETH_HLEN, VLAN_HLEN, 0); + skb->csum = csum_sub(skb->csum, vsum); + } + /* 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) { @@ -1326,6 +1362,7 @@ 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); @@ -3851,6 +3888,10 @@ 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) -- 2.7.4