From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753180Ab3FCICH (ORCPT ); Mon, 3 Jun 2013 04:02:07 -0400 Received: from mga14.intel.com ([143.182.124.37]:17771 "EHLO mga14.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752626Ab3FCIBp (ORCPT ); Mon, 3 Jun 2013 04:01:45 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.87,791,1363158000"; d="scan'208";a="311446326" From: Eliezer Tamir Subject: [PATCH v8 net-next 3/7] udp: add low latency socket poll support To: David Miller Cc: linux-kernel@vger.kernel.org, netdev@vger.kernel.org, Jesse Brandeburg , Don Skidmore , e1000-devel@lists.sourceforge.net, Willem de Bruijn , Eric Dumazet , Ben Hutchings , Andi Kleen , HPA , Eilon Greenstien , Or Gerlitz , Alex Rosenbaum , Eliezer Tamir Date: Mon, 03 Jun 2013 11:01:38 +0300 Message-ID: <20130603080138.18273.40991.stgit@ladj378.jer.intel.com> In-Reply-To: <20130603080107.18273.34279.stgit@ladj378.jer.intel.com> References: <20130603080107.18273.34279.stgit@ladj378.jer.intel.com> User-Agent: StGIT/0.14.3 MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Add upport for busy-polling on UDP sockets. In __udp[46]_lib_rcv add a call to sk_mark_ll() to copy the napi_id from the skb into the sk. This is done at the earliest possible moment, right after we identify which socket this skb is for. In __skb_recv_datagram When there is no data and the user tries to read we busy poll. Signed-off-by: Alexander Duyck Signed-off-by: Jesse Brandeburg Tested-by: Willem de Bruijn Signed-off-by: Eliezer Tamir --- net/core/datagram.c | 4 ++++ net/ipv4/udp.c | 6 +++++- net/ipv6/udp.c | 6 +++++- 3 files changed, 14 insertions(+), 2 deletions(-) diff --git a/net/core/datagram.c b/net/core/datagram.c index b71423d..9cbaba9 100644 --- a/net/core/datagram.c +++ b/net/core/datagram.c @@ -56,6 +56,7 @@ #include #include #include +#include /* * Is a socket 'connection oriented' ? @@ -207,6 +208,9 @@ struct sk_buff *__skb_recv_datagram(struct sock *sk, unsigned int flags, } spin_unlock_irqrestore(&queue->lock, cpu_flags); + if (sk_valid_ll(sk) && sk_poll_ll(sk, flags & MSG_DONTWAIT)) + continue; + /* User doesn't want to wait */ error = -EAGAIN; if (!timeo) diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c index c7338ec..2955b25 100644 --- a/net/ipv4/udp.c +++ b/net/ipv4/udp.c @@ -109,6 +109,7 @@ #include #include #include +#include #include "udp_impl.h" struct udp_table udp_table __read_mostly; @@ -1709,7 +1710,10 @@ int __udp4_lib_rcv(struct sk_buff *skb, struct udp_table *udptable, sk = __udp4_lib_lookup_skb(skb, uh->source, uh->dest, udptable); if (sk != NULL) { - int ret = udp_queue_rcv_skb(sk, skb); + int ret; + + sk_mark_ll(sk, skb); + ret = udp_queue_rcv_skb(sk, skb); sock_put(sk); /* a return value > 0 means to resubmit the input, but diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c index 42923b1..4035997 100644 --- a/net/ipv6/udp.c +++ b/net/ipv6/udp.c @@ -46,6 +46,7 @@ #include #include #include +#include #include #include @@ -841,7 +842,10 @@ int __udp6_lib_rcv(struct sk_buff *skb, struct udp_table *udptable, */ sk = __udp6_lib_lookup_skb(skb, uh->source, uh->dest, udptable); if (sk != NULL) { - int ret = udpv6_queue_rcv_skb(sk, skb); + int ret; + + sk_mark_ll(sk, skb); + ret = udpv6_queue_rcv_skb(sk, skb); sock_put(sk); /* a return value > 0 means to resubmit the input, but