From patchwork Tue Jan 22 20:52:33 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrei Vagin X-Patchwork-Id: 214657 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 14F7A2C0087 for ; Wed, 23 Jan 2013 07:55:15 +1100 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754127Ab3AVUzM (ORCPT ); Tue, 22 Jan 2013 15:55:12 -0500 Received: from mailhub.sw.ru ([195.214.232.25]:12557 "EHLO relay.sw.ru" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751267Ab3AVUzK (ORCPT ); Tue, 22 Jan 2013 15:55:10 -0500 Received: from localhost.localdomain ([10.24.21.14]) by relay.sw.ru (8.13.4/8.13.4) with ESMTP id r0MKrsbY008878; Wed, 23 Jan 2013 00:53:55 +0400 (MSK) From: Andrey Vagin To: netdev@vger.kernel.org Cc: criu@openvz.org, linux-kernel@vger.kernel.org, Andrey Vagin , "David S. Miller" , Alexey Kuznetsov , James Morris , Hideaki YOSHIFUJI , Patrick McHardy , Eric Dumazet , Yuchung Cheng , Neal Cardwell , Pavel Emelyanov , Dave Jones , Michael Kerrisk Subject: [PATCH net-next] tcp: add ability to set a timestamp offset Date: Wed, 23 Jan 2013 00:52:33 +0400 Message-Id: <1358887953-28665-1-git-send-email-avagin@openvz.org> X-Mailer: git-send-email 1.7.11.7 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org If a TCP socket will get live-migrated from one box to another the timestamps (which are typically ON) will get screwed up -- the new kernel will generate TS values that has nothing to do with what they were on dump. The solution is to yet again fix the kernel and put a "timestamp offset" on a socket. Cc: "David S. Miller" Cc: Alexey Kuznetsov Cc: James Morris Cc: Hideaki YOSHIFUJI Cc: Patrick McHardy Cc: Eric Dumazet Cc: Yuchung Cheng Cc: Neal Cardwell Cc: Pavel Emelyanov Cc: Dave Jones Cc: Michael Kerrisk Signed-off-by: Andrey Vagin --- include/linux/tcp.h | 2 ++ include/uapi/linux/tcp.h | 1 + net/ipv4/tcp.c | 6 ++++++ net/ipv4/tcp_output.c | 7 ++++--- 4 files changed, 13 insertions(+), 3 deletions(-) diff --git a/include/linux/tcp.h b/include/linux/tcp.h index 4e1d228..746dad5 100644 --- a/include/linux/tcp.h +++ b/include/linux/tcp.h @@ -162,6 +162,8 @@ struct tcp_sock { u32 rcv_tstamp; /* timestamp of last received ACK (for keepalives) */ u32 lsndtime; /* timestamp of last sent data packet (for restart window) */ + u32 snd_tsval_offset; /* offset for snd_tsval */ + struct list_head tsq_node; /* anchor in tsq_tasklet.head list */ unsigned long tsq_flags; diff --git a/include/uapi/linux/tcp.h b/include/uapi/linux/tcp.h index e962faa..6b1ead0 100644 --- a/include/uapi/linux/tcp.h +++ b/include/uapi/linux/tcp.h @@ -111,6 +111,7 @@ enum { #define TCP_QUEUE_SEQ 21 #define TCP_REPAIR_OPTIONS 22 #define TCP_FASTOPEN 23 /* Enable FastOpen on listeners */ +#define TCP_TIMESTAMP 24 struct tcp_repair_opt { __u32 opt_code; diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index 1ca2536..72dee28 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -2704,6 +2704,9 @@ static int do_tcp_setsockopt(struct sock *sk, int level, else err = -EINVAL; break; + case TCP_TIMESTAMP: + tp->snd_tsval_offset = val - tcp_time_stamp; + break; default: err = -ENOPROTOOPT; break; @@ -2952,6 +2955,9 @@ static int do_tcp_getsockopt(struct sock *sk, int level, case TCP_USER_TIMEOUT: val = jiffies_to_msecs(icsk->icsk_user_timeout); break; + case TCP_TIMESTAMP: + val = tcp_time_stamp + tp->snd_tsval_offset; + break; default: return -ENOPROTOOPT; } diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c index 5d45159..9b6d485 100644 --- a/net/ipv4/tcp_output.c +++ b/net/ipv4/tcp_output.c @@ -622,7 +622,7 @@ static unsigned int tcp_syn_options(struct sock *sk, struct sk_buff *skb, if (likely(sysctl_tcp_timestamps && *md5 == NULL)) { opts->options |= OPTION_TS; - opts->tsval = TCP_SKB_CB(skb)->when; + opts->tsval = TCP_SKB_CB(skb)->when + tp->snd_tsval_offset; opts->tsecr = tp->rx_opt.ts_recent; remaining -= TCPOLEN_TSTAMP_ALIGNED; } @@ -705,6 +705,7 @@ static unsigned int tcp_synack_options(struct sock *sk, struct tcp_extend_values *xvp, struct tcp_fastopen_cookie *foc) { + struct tcp_sock *tp = tcp_sk(sk); struct inet_request_sock *ireq = inet_rsk(req); unsigned int remaining = MAX_TCP_OPTION_SPACE; u8 cookie_plus = (xvp != NULL && !xvp->cookie_out_never) ? @@ -739,7 +740,7 @@ static unsigned int tcp_synack_options(struct sock *sk, } if (likely(ireq->tstamp_ok)) { opts->options |= OPTION_TS; - opts->tsval = TCP_SKB_CB(skb)->when; + opts->tsval = TCP_SKB_CB(skb)->when + tp->snd_tsval_offset; opts->tsecr = req->ts_recent; remaining -= TCPOLEN_TSTAMP_ALIGNED; } @@ -806,7 +807,7 @@ static unsigned int tcp_established_options(struct sock *sk, struct sk_buff *skb if (likely(tp->rx_opt.tstamp_ok)) { opts->options |= OPTION_TS; - opts->tsval = tcb ? tcb->when : 0; + opts->tsval = tcb ? tcb->when + tp->snd_tsval_offset : 0; opts->tsecr = tp->rx_opt.ts_recent; size += TCPOLEN_TSTAMP_ALIGNED; }