From patchwork Tue Jun 24 15:43:49 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Willem de Bruijn X-Patchwork-Id: 363499 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 861CA1400AB for ; Wed, 25 Jun 2014 01:48:57 +1000 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754534AbaFXPoC (ORCPT ); Tue, 24 Jun 2014 11:44:02 -0400 Received: from mail-pd0-f201.google.com ([209.85.192.201]:37368 "EHLO mail-pd0-f201.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754366AbaFXPoA (ORCPT ); Tue, 24 Jun 2014 11:44:00 -0400 Received: by mail-pd0-f201.google.com with SMTP id v10so62699pde.4 for ; Tue, 24 Jun 2014 08:43:59 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20120113; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=/MDXdn304KSqVUmUetvT/Pr6CtbuiaUtfEsSqMIcOTM=; b=ndDjhjjQwO+AlX7HFARKOhVg0ZfvBK/7Apt1zULKelQ97oQO6zM0UjLQTGc5EXQ6M4 1p9nCAjb0mWuqoKswBDL6juQXmUX2BNkJzuurVCMrs5FMPO3iI2vUis8RHW3dl5fB1Gc 7OyPAAbupG/hyLyXXJaGU803HJ0KrGiBfEzrPezknInBPysfwDnn0PCDJzoh0kawu3au vH2no++IA8GIp8nrvav9LX4DogHeHBftt6ngNOAQgUOACIiCA5bG8s0ZYu7IuiJk8BJ0 vOBcz0vzWGxZyI8WtlMYDmMK8NUqRmc16DP08JVTG7PER0SxhtsWtSM28zpFpIcn6aWE Ppig== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=/MDXdn304KSqVUmUetvT/Pr6CtbuiaUtfEsSqMIcOTM=; b=DJOnrpRredNvW06RxtD9xXl5PZz9zsqQd/UAp9ocDiudFp1w9CpDMEM0gu4gpsEWtl jZNpBnDKINgXSDPSv7lfUWIP/ZwdKmlNo+Afq7jKrr9V5nzmBJa0WWa2ZPMy5umlSSOm EBupZ4SkO8mxyivh7jo9hNejWMFwkf8HPuw7kPU/eIvO2Qa0sLsGH3ldZW4hFpeTVf3v IdM0siLMz4hX2jf4B+IiR5PSEpkBzGuRiy1KerYaH/m0PvlQIclZlWraMQwMqBRxl8is DGrzM21auP0csLhnR9ZbrTuMZN1LgGPu0OuANrMUvG4mm4itxmTaClRn3Vye+3zvVwQr f0FQ== X-Gm-Message-State: ALoCoQktRqCPhjKubk3btfWQkHwEVW0z2oeYPCJpldMZHXNWNJRQbrLgHn8FEq6cQiEjAqI8/NWP X-Received: by 10.66.151.140 with SMTP id uq12mr829861pab.23.1403624639775; Tue, 24 Jun 2014 08:43:59 -0700 (PDT) Received: from corp2gmr1-2.hot.corp.google.com (corp2gmr1-2.hot.corp.google.com [172.24.189.93]) by gmr-mx.google.com with ESMTPS id j5si56194yhi.1.2014.06.24.08.43.59 for (version=TLSv1.1 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Tue, 24 Jun 2014 08:43:59 -0700 (PDT) Received: from gopher.nyc.corp.google.com (gopher.nyc.corp.google.com [172.26.106.37]) by corp2gmr1-2.hot.corp.google.com (Postfix) with ESMTP id 984745A44B0; Tue, 24 Jun 2014 08:43:59 -0700 (PDT) Received: by gopher.nyc.corp.google.com (Postfix, from userid 29878) id 47ED3C0958; Tue, 24 Jun 2014 11:43:59 -0400 (EDT) From: Willem de Bruijn To: netdev@vger.kernel.org Cc: eric.dumazet@gmail.com, richardcochran@gmail.com, davem@davemloft.net, Willem de Bruijn Subject: [PATCH net-next 4/7] net-timestamp: TCP timestamping Date: Tue, 24 Jun 2014 11:43:49 -0400 Message-Id: <1403624632-17327-5-git-send-email-willemb@google.com> X-Mailer: git-send-email 2.0.0.526.g5318336 In-Reply-To: <1403624632-17327-1-git-send-email-willemb@google.com> References: <1403624632-17327-1-git-send-email-willemb@google.com> Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org TCP timestamping extends datagram MSG_TSTAMP support to bytestreams. Bytestreams do not have a 1:1 relationship between send() buffers and network packets. The feature interprets a send call with MSG_TSTAMP on a bytestream as a request for a timestamp for the last byte in the buffer. The choice corresponds to a request for a timestamp when all bytes in the buffer have been sent. That assumption depends on in-order kernel transmission. This is the common case. That said, it is possible to construct a traffic shaping tree that would result in reordering. The guarantee is strong, then, but not ironclad. This implementation supports send and sendpages (splice). GSO replaces one large packet with multiple smaller packets. This patch also copies the option into the correct smaller packet. This patch does not yet support timestamping on data in an initial TCP Fast Open SYN, because that takes a very different data path. The implementation supports a single timestamp per packet. To avoid having multiple timestamp requests per sk_buff, the skb is locked against extension once the flag is set. Signed-off-by: Willem de Bruijn --- net/core/skbuff.c | 12 ++++++++++++ net/ipv4/tcp.c | 21 +++++++++++++++++---- net/ipv4/tcp_offload.c | 4 ++++ net/socket.c | 2 ++ 4 files changed, 35 insertions(+), 4 deletions(-) diff --git a/net/core/skbuff.c b/net/core/skbuff.c index bc653c4..07ba98d 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -69,6 +69,7 @@ #include #include #include +#include #include #include @@ -3496,6 +3497,7 @@ void skb_tstamp_tx(struct sk_buff *orig_skb, struct sock *sk = orig_skb->sk; struct sock_exterr_skb *serr; struct sk_buff *skb; + __u32 key = 0; int err; if (!sk) @@ -3525,10 +3527,20 @@ void skb_tstamp_tx(struct sk_buff *orig_skb, *skb_hwtstamps(skb) = *skb_hwtstamps(orig_skb); } + if (orig_skb->sk && orig_skb->sk->sk_protocol == IPPROTO_TCP) { + if (orig_skb->fclone == SKB_FCLONE_CLONE) + key = TCP_SKB_CB(orig_skb - 1)->end_seq; + else /* after GSO segmentation, clone no longer works */ + key = ntohl(tcp_hdr(skb)->seq) + + ntohs(ip_hdr(skb)->tot_len) - + ip_hdrlen(skb) - tcp_hdrlen(skb); + } + serr = SKB_EXT_ERR(skb); memset(serr, 0, sizeof(*serr)); serr->ee.ee_errno = ENOMSG; serr->ee.ee_origin = SO_EE_ORIGIN_TIMESTAMPING; + serr->ee.ee_data = key; err = sock_queue_err_skb(sk, skb); diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index eb1dde3..4ceecd9 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -878,6 +878,11 @@ static int tcp_send_mss(struct sock *sk, int *size_goal, int flags) return mss_now; } +static bool tcp_skb_can_extend(struct sk_buff *skb) +{ + return !(skb_shinfo(skb)->tx_flags & SKBTX_SW_TSTAMP); +} + static ssize_t do_tcp_sendpages(struct sock *sk, struct page *page, int offset, size_t size, int flags) { @@ -911,7 +916,8 @@ static ssize_t do_tcp_sendpages(struct sock *sk, struct page *page, int offset, int copy, i; bool can_coalesce; - if (!tcp_send_head(sk) || (copy = size_goal - skb->len) <= 0) { + if (!tcp_send_head(sk) || (copy = size_goal - skb->len) <= 0 || + !tcp_skb_can_extend(skb)) { new_segment: if (!sk_stream_memory_free(sk)) goto wait_for_sndbuf; @@ -959,8 +965,10 @@ new_segment: copied += copy; offset += copy; - if (!(size -= copy)) + if (!(size -= copy)) { + skb_shinfo(skb)->tx_flags |= skbflags_tx_tstamp(flags); goto out; + } if (skb->len < size_goal || (flags & MSG_OOB)) continue; @@ -1160,7 +1168,7 @@ int tcp_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg, copy = max - skb->len; } - if (copy <= 0) { + if (copy <= 0 || !tcp_skb_can_extend(skb)) { new_segment: /* Allocate new segment. If the interface is SG, * allocate skb fitting to single page. @@ -1252,8 +1260,10 @@ new_segment: from += copy; copied += copy; - if ((seglen -= copy) == 0 && iovlen == 0) + if ((seglen -= copy) == 0 && iovlen == 0) { + skb_shinfo(skb)->tx_flags |= skbflags_tx_tstamp(flags); goto out; + } if (skb->len < max || (flags & MSG_OOB) || unlikely(tp->repair)) continue; @@ -1616,6 +1626,9 @@ int tcp_recvmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg, struct sk_buff *skb; u32 urg_hole = 0; + if (unlikely(flags & MSG_ERRQUEUE)) + return ip_recv_error(sk, msg, len, addr_len); + if (sk_can_busy_loop(sk) && skb_queue_empty(&sk->sk_receive_queue) && (sk->sk_state == TCP_ESTABLISHED)) sk_busy_loop(sk, nonblock); diff --git a/net/ipv4/tcp_offload.c b/net/ipv4/tcp_offload.c index 4e86c59..730c2f6 100644 --- a/net/ipv4/tcp_offload.c +++ b/net/ipv4/tcp_offload.c @@ -134,6 +134,10 @@ struct sk_buff *tcp_gso_segment(struct sk_buff *skb, (__force u32)delta)); if (skb->ip_summed != CHECKSUM_PARTIAL) th->check = gso_make_checksum(skb, ~th->check); + + if (unlikely(skb_shinfo(gso_skb)->tx_flags & SKBTX_SW_TSTAMP)) + skb_shinfo(skb)->tx_flags |= SKBTX_SW_TSTAMP; + out: return segs; } diff --git a/net/socket.c b/net/socket.c index 18ab44a..d01e323 100644 --- a/net/socket.c +++ b/net/socket.c @@ -697,6 +697,7 @@ EXPORT_SYMBOL(kernel_sendmsg); void __sock_recv_timestamp(struct msghdr *msg, struct sock *sk, struct sk_buff *skb) { + struct sock_exterr_skb *serr = SKB_EXT_ERR(skb); int need_software_tstamp = sock_flag(sk, SOCK_RCVTSTAMP); struct sock_errqueue_timestamping tss; int empty = 1; @@ -727,6 +728,7 @@ void __sock_recv_timestamp(struct msghdr *msg, struct sock *sk, skb_shinfo(skb)->tx_flags & SKBTX_SW_TSTAMP) && ktime_to_timespec_cond(skb->tstamp, &tss.ts_sw)) { empty = 0; + tss.ts_key = serr->ee.ee_data; tss.ts_type = SCM_TSTAMP_SND; } if (shhwtstamps) {