From mboxrd@z Thu Jan 1 00:00:00 1970 From: Eric Dumazet Subject: Re: [PATCH v4 net-next 09/11] net: Add IPv6 flow label to flow_keys Date: Thu, 28 May 2015 17:36:36 -0700 Message-ID: <1432859796.7456.53.camel@edumazet-glaptop2.roam.corp.google.com> References: <1432837148-1359931-1-git-send-email-tom@herbertland.com> <1432837148-1359931-10-git-send-email-tom@herbertland.com> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Cc: davem@davemloft.net, netdev@vger.kernel.org To: Tom Herbert Return-path: Received: from mail-ig0-f177.google.com ([209.85.213.177]:38279 "EHLO mail-ig0-f177.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754794AbbE2Agj (ORCPT ); Thu, 28 May 2015 20:36:39 -0400 Received: by igbjd9 with SMTP id jd9so2485525igb.1 for ; Thu, 28 May 2015 17:36:38 -0700 (PDT) In-Reply-To: <1432837148-1359931-10-git-send-email-tom@herbertland.com> Sender: netdev-owner@vger.kernel.org List-ID: On Thu, 2015-05-28 at 11:19 -0700, Tom Herbert wrote: > In flow_dissector set the flow label in flow_keys for IPv6. This also > removes the shortcircuiting of flow dissection when a non-zero label > is present, the flow label can be considered to provide additional > entropy for a hash. > > Signed-off-by: Tom Herbert > --- > include/net/flow_dissector.h | 4 +++- > net/core/flow_dissector.c | 31 +++++++++++-------------------- > 2 files changed, 14 insertions(+), 21 deletions(-) > > diff --git a/include/net/flow_dissector.h b/include/net/flow_dissector.h > index 08480fb..14d8483 100644 > --- a/include/net/flow_dissector.h > +++ b/include/net/flow_dissector.h > @@ -28,7 +28,8 @@ struct flow_dissector_key_basic { > }; > > struct flow_dissector_key_tags { > - u32 vlan_id:12; > + u32 vlan_id:12, > + flow_label:20; > }; > > /** > @@ -111,6 +112,7 @@ enum flow_dissector_key_id { > FLOW_DISSECTOR_KEY_ETH_ADDRS, /* struct flow_dissector_key_eth_addrs */ > FLOW_DISSECTOR_KEY_TIPC_ADDRS, /* struct flow_dissector_key_tipc_addrs */ > FLOW_DISSECTOR_KEY_VLANID, /* struct flow_dissector_key_flow_tags */ > + FLOW_DISSECTOR_KEY_FLOW_LABEL, /* struct flow_dissector_key_flow_tags */ > > FLOW_DISSECTOR_KEY_MAX, > }; > diff --git a/net/core/flow_dissector.c b/net/core/flow_dissector.c > index 5c66cb2..ba089d9 100644 > --- a/net/core/flow_dissector.c > +++ b/net/core/flow_dissector.c > @@ -190,7 +190,7 @@ ip: > case htons(ETH_P_IPV6): { > const struct ipv6hdr *iph; > struct ipv6hdr _iph; > - __be32 flow_label; > + u32 flow_label; You change flow_label from __be32 to u32. > > ipv6: > iph = __skb_header_pointer(skb, nhoff, sizeof(_iph), data, hlen, &_iph); > @@ -210,30 +210,17 @@ ipv6: > > memcpy(key_ipv6_addrs, &iph->saddr, sizeof(*key_ipv6_addrs)); > key_control->addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS; > - goto flow_label; > } > - break; > -flow_label: > + > flow_label = ip6_flowlabel(iph); But ip6_flowlabel() returns a __be32. This should not please sparse. > if (flow_label) { > - /* Awesome, IPv6 packet has a flow label so we can > - * use that to represent the ports without any > - * further dissection. > - */ > - > - key_basic->n_proto = proto; > - key_basic->ip_proto = ip_proto; > - key_control->thoff = (u16)nhoff; > - > if (skb_flow_dissector_uses_key(flow_dissector, > - FLOW_DISSECTOR_KEY_PORTS)) { > - key_ports = skb_flow_dissector_target(flow_dissector, > - FLOW_DISSECTOR_KEY_PORTS, > - target_container); > - key_ports->ports = flow_label; > + FLOW_DISSECTOR_KEY_FLOW_LABEL)) { > + key_tags = skb_flow_dissector_target(flow_dissector, > + FLOW_DISSECTOR_KEY_FLOW_LABEL, > + target_container); > + key_tags->flow_label = ntohl(flow_label); Then you call ntohl() on u32 variable. This should also complain. Have you run sparse ? make C=2 CF=-D__CHECK_ENDIAN__ net/core/flow_dissector.o Thanks.