From mboxrd@z Thu Jan 1 00:00:00 1970 From: Eric Dumazet Subject: [PATCH net-next] gro: introduce gro_mac_header_len Date: Mon, 06 Feb 2012 17:27:07 +0100 Message-ID: <1328545627.2220.72.camel@edumazet-HP-Compaq-6005-Pro-SFF-PC> References: <1828884A29C6694DAF28B7E6B8A823733349A5D2@ORSMSX101.amr.corp.intel.com> <1328259640.2480.43.camel@edumazet-laptop> <1828884A29C6694DAF28B7E6B8A823733349A6C9@ORSMSX101.amr.corp.intel.com> <4F2FEC36.6090800@mellanox.com> <1328541706.2220.50.camel@edumazet-HP-Compaq-6005-Pro-SFF-PC> <4F2FF050.7040400@mellanox.com> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Cc: "Hefty, Sean" , Herbert Xu , linux-rdma , Shlomo Pongratz , Roland Dreier , "netdev-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" To: Or Gerlitz Return-path: In-Reply-To: <4F2FF050.7040400-VPRAkNaXOzVWk0Htik3J/w@public.gmane.org> Sender: linux-rdma-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: netdev.vger.kernel.org Shlomo Pongratz reported GRO L2 header check was suited for Ethernet only, and failed on IB/ipoib traffic. He provided a patch faking a zeroed header to let GRO aggregates frames. Roland Dreier, Herbert Xu, and others suggested we change GRO L2 header check to be more generic. This patch introduces a new netdevice field, gro_mac_header_len, giving L2 header length, default to ETH_HLEN (14 bytes) A device setup function can override this default value. __napi_gro_receive() has special handling for the common case (Ethernet) to avoid a memcmp() call and use an inline optimized function instead. Signed-off-by: Eric Dumazet Reported-by: Shlomo Pongratz Cc: Roland Dreier Cc: Or Gerlitz Cc: Herbert Xu --- include/linux/netdevice.h | 1 + net/core/dev.c | 11 +++++++++-- 2 files changed, 10 insertions(+), 2 deletions(-) diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index 0eac07c..d17192b 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -1095,6 +1095,7 @@ struct net_device { unsigned int mtu; /* interface MTU value */ unsigned short type; /* interface hardware type */ unsigned short hard_header_len; /* hardware hdr length */ + unsigned int gro_mac_header_len; /* extra head- and tailroom the hardware may need, but not in all cases * can this be guaranteed, especially tailroom. Some cases also use diff --git a/net/core/dev.c b/net/core/dev.c index f124947..0b43939 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -3491,14 +3491,20 @@ static inline gro_result_t __napi_gro_receive(struct napi_struct *napi, struct sk_buff *skb) { struct sk_buff *p; + unsigned int maclen = skb->dev->gro_mac_header_len; for (p = napi->gro_list; p; p = p->next) { unsigned long diffs; diffs = (unsigned long)p->dev ^ (unsigned long)skb->dev; diffs |= p->vlan_tci ^ skb->vlan_tci; - diffs |= compare_ether_header(skb_mac_header(p), - skb_gro_mac_header(skb)); + if (maclen == ETH_HLEN) + diffs |= compare_ether_header(skb_mac_header(p), + skb_gro_mac_header(skb)); + else if (!diffs) + diffs = memcmp(skb_mac_header(p), + skb_gro_mac_header(skb), + maclen); NAPI_GRO_CB(p)->same_flow = !diffs; NAPI_GRO_CB(p)->flush = 0; } @@ -5962,6 +5968,7 @@ struct net_device *alloc_netdev_mqs(int sizeof_priv, const char *name, INIT_LIST_HEAD(&dev->unreg_list); INIT_LIST_HEAD(&dev->link_watch_list); dev->priv_flags = IFF_XMIT_DST_RELEASE; + dev->gro_mac_header_len = ETH_HLEN; setup(dev); dev->num_tx_queues = txqs; -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html