{"id":817702,"url":"http://patchwork.ozlabs.org/api/patches/817702/?format=json","web_url":"http://patchwork.ozlabs.org/project/netdev/patch/96345ae1e2ecc6fa8b2525b324d986a52da2847a.1506114055.git.pabeni@redhat.com/","project":{"id":7,"url":"http://patchwork.ozlabs.org/api/projects/7/?format=json","name":"Linux network development","link_name":"netdev","list_id":"netdev.vger.kernel.org","list_email":"netdev@vger.kernel.org","web_url":null,"scm_url":null,"webscm_url":null,"list_archive_url":"","list_archive_url_format":"","commit_url_format":""},"msgid":"<96345ae1e2ecc6fa8b2525b324d986a52da2847a.1506114055.git.pabeni@redhat.com>","list_archive_url":null,"date":"2017-09-22T21:06:27","name":"[RFC,03/11] udp: do not touch socket refcount in early demux","commit_ref":null,"pull_url":null,"state":"rfc","archived":true,"hash":"025b3e69ec75f2575d398ec289dc3ad6e9b78d58","submitter":{"id":67312,"url":"http://patchwork.ozlabs.org/api/people/67312/?format=json","name":"Paolo Abeni","email":"pabeni@redhat.com"},"delegate":{"id":34,"url":"http://patchwork.ozlabs.org/api/users/34/?format=json","username":"davem","first_name":"David","last_name":"Miller","email":"davem@davemloft.net"},"mbox":"http://patchwork.ozlabs.org/project/netdev/patch/96345ae1e2ecc6fa8b2525b324d986a52da2847a.1506114055.git.pabeni@redhat.com/mbox/","series":[{"id":4709,"url":"http://patchwork.ozlabs.org/api/series/4709/?format=json","web_url":"http://patchwork.ozlabs.org/project/netdev/list/?series=4709","date":"2017-09-22T21:06:24","name":"udp: full early demux for unconnected sockets","version":1,"mbox":"http://patchwork.ozlabs.org/series/4709/mbox/"}],"comments":"http://patchwork.ozlabs.org/api/patches/817702/comments/","check":"pending","checks":"http://patchwork.ozlabs.org/api/patches/817702/checks/","tags":{},"related":[],"headers":{"Return-Path":"","X-Original-To":"patchwork-incoming@ozlabs.org","Delivered-To":"patchwork-incoming@ozlabs.org","Authentication-Results":["ozlabs.org;\n\tspf=none (mailfrom) smtp.mailfrom=vger.kernel.org\n\t(client-ip=209.132.180.67; helo=vger.kernel.org;\n\tenvelope-from=netdev-owner@vger.kernel.org;\n\treceiver=)","ext-mx04.extmail.prod.ext.phx2.redhat.com;\n\tdmarc=none (p=none dis=none) header.from=redhat.com","ext-mx04.extmail.prod.ext.phx2.redhat.com;\n\tspf=fail smtp.mailfrom=pabeni@redhat.com"],"Received":["from vger.kernel.org (vger.kernel.org [209.132.180.67])\n\tby ozlabs.org (Postfix) with ESMTP id 3xzQyy2Nj5z9sP1\n\tfor ;\n\tSat, 23 Sep 2017 07:07:06 +1000 (AEST)","(majordomo@vger.kernel.org) by vger.kernel.org via listexpand\n\tid S1752709AbdIVVHD (ORCPT );\n\tFri, 22 Sep 2017 17:07:03 -0400","from mx1.redhat.com ([209.132.183.28]:42220 \"EHLO mx1.redhat.com\"\n\trhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP\n\tid S1752694AbdIVVHC (ORCPT );\n\tFri, 22 Sep 2017 17:07:02 -0400","from smtp.corp.redhat.com\n\t(int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15])\n\t(using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits))\n\t(No client certificate requested)\n\tby mx1.redhat.com (Postfix) with ESMTPS id 376337EA9F;\n\tFri, 22 Sep 2017 21:07:02 +0000 (UTC)","from dhcppc0.redhat.com (ovpn-116-39.ams2.redhat.com\n\t[10.36.116.39])\n\tby smtp.corp.redhat.com (Postfix) with ESMTP id 813DD5D6A2;\n\tFri, 22 Sep 2017 21:07:00 +0000 (UTC)"],"DMARC-Filter":"OpenDMARC Filter v1.3.2 mx1.redhat.com 376337EA9F","From":"Paolo Abeni ","To":"netdev@vger.kernel.org","Cc":"\"David S. Miller\" ,\n\tPablo Neira Ayuso , Florian Westphal ,\n\tEric Dumazet ,\n\tHannes Frederic Sowa ","Subject":"[RFC PATCH 03/11] udp: do not touch socket refcount in early demux","Date":"Fri, 22 Sep 2017 23:06:27 +0200","Message-Id":"<96345ae1e2ecc6fa8b2525b324d986a52da2847a.1506114055.git.pabeni@redhat.com>","In-Reply-To":"","References":"","X-Scanned-By":"MIMEDefang 2.79 on 10.5.11.15","X-Greylist":"Sender IP whitelisted, not delayed by milter-greylist-4.5.16\n\t(mx1.redhat.com [10.5.110.28]);\n\tFri, 22 Sep 2017 21:07:02 +0000 (UTC)","Sender":"netdev-owner@vger.kernel.org","Precedence":"bulk","List-ID":"","X-Mailing-List":"netdev@vger.kernel.org"},"content":"use noref sockets instead. This gives some small performance\nimprovements and will allow efficient early demux for unconnected\nsockets in a later patch.\n\nSigned-off-by: Paolo Abeni \n---\n net/ipv4/udp.c | 18 ++++++++++--------\n net/ipv6/udp.c | 10 ++++++----\n 2 files changed, 16 insertions(+), 12 deletions(-)","diff":"diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c\nindex 784ced0b9150..ba49d5aa9f09 100644\n--- a/net/ipv4/udp.c\n+++ b/net/ipv4/udp.c\n@@ -2050,12 +2050,13 @@ static inline int udp4_csum_init(struct sk_buff *skb, struct udphdr *uh,\n int __udp4_lib_rcv(struct sk_buff *skb, struct udp_table *udptable,\n \t\t int proto)\n {\n-\tstruct sock *sk;\n-\tstruct udphdr *uh;\n-\tunsigned short ulen;\n+\tstruct net *net = dev_net(skb->dev);\n \tstruct rtable *rt = skb_rtable(skb);\n+\tunsigned short ulen;\n \t__be32 saddr, daddr;\n-\tstruct net *net = dev_net(skb->dev);\n+\tstruct udphdr *uh;\n+\tstruct sock *sk;\n+\tbool noref_sk;\n \n \t/*\n \t * Validate the packet.\n@@ -2081,6 +2082,7 @@ int __udp4_lib_rcv(struct sk_buff *skb, struct udp_table *udptable,\n \tif (udp4_csum_init(skb, uh, proto))\n \t\tgoto csum_error;\n \n+\tnoref_sk = skb_has_noref_sk(skb);\n \tsk = skb_steal_sock(skb);\n \tif (sk) {\n \t\tstruct dst_entry *dst = skb_dst(skb);\n@@ -2090,7 +2092,8 @@ int __udp4_lib_rcv(struct sk_buff *skb, struct udp_table *udptable,\n \t\t\tudp_sk_rx_dst_set(sk, dst);\n \n \t\tret = udp_queue_rcv_skb(sk, skb);\n-\t\tsock_put(sk);\n+\t\tif (!noref_sk)\n+\t\t\tsock_put(sk);\n \t\t/* a return value > 0 means to resubmit the input, but\n \t\t * it wants the return to be -protocol, or 0\n \t\t */\n@@ -2261,11 +2264,10 @@ void udp_v4_early_demux(struct sk_buff *skb)\n \t\t\t\t\t uh->source, iph->saddr, dif, sdif);\n \t}\n \n-\tif (!sk || !refcount_inc_not_zero(&sk->sk_refcnt))\n+\tif (!sk)\n \t\treturn;\n \n-\tskb->sk = sk;\n-\tskb->destructor = sock_efree;\n+\tskb_set_noref_sk(skb, sk);\n \tdst = READ_ONCE(sk->sk_rx_dst);\n \n \tif (dst)\ndiff --git a/net/ipv6/udp.c b/net/ipv6/udp.c\nindex e2ecfb137297..8f62392c4c35 100644\n--- a/net/ipv6/udp.c\n+++ b/net/ipv6/udp.c\n@@ -787,6 +787,7 @@ int __udp6_lib_rcv(struct sk_buff *skb, struct udp_table *udptable,\n \tstruct net *net = dev_net(skb->dev);\n \tstruct udphdr *uh;\n \tstruct sock *sk;\n+\tbool noref_sk;\n \tu32 ulen = 0;\n \n \tif (!pskb_may_pull(skb, sizeof(struct udphdr)))\n@@ -823,6 +824,7 @@ int __udp6_lib_rcv(struct sk_buff *skb, struct udp_table *udptable,\n \t\tgoto csum_error;\n \n \t/* Check if the socket is already available, e.g. due to early demux */\n+\tnoref_sk = skb_has_noref_sk(skb);\n \tsk = skb_steal_sock(skb);\n \tif (sk) {\n \t\tstruct dst_entry *dst = skb_dst(skb);\n@@ -832,7 +834,8 @@ int __udp6_lib_rcv(struct sk_buff *skb, struct udp_table *udptable,\n \t\t\tudp6_sk_rx_dst_set(sk, dst);\n \n \t\tret = udpv6_queue_rcv_skb(sk, skb);\n-\t\tsock_put(sk);\n+\t\tif (!noref_sk)\n+\t\t\tsock_put(sk);\n \n \t\t/* a return value > 0 means to resubmit the input */\n \t\tif (ret > 0)\n@@ -948,11 +951,10 @@ static void udp_v6_early_demux(struct sk_buff *skb)\n \telse\n \t\treturn;\n \n-\tif (!sk || !refcount_inc_not_zero(&sk->sk_refcnt))\n+\tif (!sk)\n \t\treturn;\n \n-\tskb->sk = sk;\n-\tskb->destructor = sock_efree;\n+\tskb_set_noref_sk(skb, sk);\n \tdst = READ_ONCE(sk->sk_rx_dst);\n \n \tif (dst)\n","prefixes":["RFC","03/11"]}