From mboxrd@z Thu Jan 1 00:00:00 1970 From: Wei Wang Subject: [PATCH net-next 4/4] tcp: add stat of data packet reordering events Date: Mon, 30 Jul 2018 14:59:11 -0700 Message-ID: <20180730215911.209895-5-tracywwnj@gmail.com> References: <20180730215911.209895-1-tracywwnj@gmail.com> <20180730215911.209895-2-tracywwnj@gmail.com> <20180730215911.209895-3-tracywwnj@gmail.com> <20180730215911.209895-4-tracywwnj@gmail.com> Mime-Version: 1.0 Content-Transfer-Encoding: 8bit Cc: Yuchung Cheng , Neal Cardwell , Soheil Hassas Yeganeh , Eric Dumazet , Wei Wang To: David Miller , netdev@vger.kernel.org Return-path: Received: from mail-pl0-f67.google.com ([209.85.160.67]:37321 "EHLO mail-pl0-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726622AbeG3XjQ (ORCPT ); Mon, 30 Jul 2018 19:39:16 -0400 Received: by mail-pl0-f67.google.com with SMTP id d5-v6so617730pll.4 for ; Mon, 30 Jul 2018 15:02:15 -0700 (PDT) In-Reply-To: <20180730215911.209895-4-tracywwnj@gmail.com> Sender: netdev-owner@vger.kernel.org List-ID: From: Wei Wang Introduce a new TCP stats to record the number of reordering events seen and expose it in both tcp_info (TCP_INFO) and opt_stats (SOF_TIMESTAMPING_OPT_STATS). Application can use this stats to track the frequency of the reordering events in addition to the existing reordering stats which tracks the magnitude of the latest reordering event. Note: this new stats tracks reordering events triggered by ACKs, which could often be fewer than the actual number of packets being delivered out-of-order. Signed-off-by: Wei Wang Signed-off-by: Eric Dumazet Acked-by: Neal Cardwell Acked-by: Soheil Hassas Yeganeh Acked-by: Yuchung Cheng --- include/linux/tcp.h | 4 ++-- include/uapi/linux/tcp.h | 2 ++ net/ipv4/tcp.c | 5 ++++- net/ipv4/tcp_input.c | 3 ++- net/ipv4/tcp_recovery.c | 2 +- 5 files changed, 11 insertions(+), 5 deletions(-) diff --git a/include/linux/tcp.h b/include/linux/tcp.h index da6281c549a5..263e37271afd 100644 --- a/include/linux/tcp.h +++ b/include/linux/tcp.h @@ -220,8 +220,7 @@ struct tcp_sock { #define TCP_RACK_RECOVERY_THRESH 16 u8 reo_wnd_persist:5, /* No. of recovery since last adj */ dsack_seen:1, /* Whether DSACK seen after last adj */ - advanced:1, /* mstamp advanced since last lost marking */ - reord:1; /* reordering detected */ + advanced:1; /* mstamp advanced since last lost marking */ } rack; u16 advmss; /* Advertised MSS */ u8 compressed_ack; @@ -267,6 +266,7 @@ struct tcp_sock { u8 ecn_flags; /* ECN status bits. */ u8 keepalive_probes; /* num of allowed keep alive probes */ u32 reordering; /* Packet reordering metric. */ + u32 reord_seen; /* number of data packet reordering events */ u32 snd_up; /* Urgent pointer */ /* diff --git a/include/uapi/linux/tcp.h b/include/uapi/linux/tcp.h index 0e1c0aec0153..e02d31986ff9 100644 --- a/include/uapi/linux/tcp.h +++ b/include/uapi/linux/tcp.h @@ -239,6 +239,7 @@ struct tcp_info { __u64 tcpi_bytes_sent; /* RFC4898 tcpEStatsPerfHCDataOctetsOut */ __u64 tcpi_bytes_retrans; /* RFC4898 tcpEStatsPerfOctetsRetrans */ __u32 tcpi_dsack_dups; /* RFC4898 tcpEStatsStackDSACKDups */ + __u32 tcpi_reord_seen; /* reordering events seen */ }; /* netlink attributes types for SCM_TIMESTAMPING_OPT_STATS */ @@ -264,6 +265,7 @@ enum { TCP_NLA_BYTES_SENT, /* Data bytes sent including retransmission */ TCP_NLA_BYTES_RETRANS, /* Data bytes retransmitted */ TCP_NLA_DSACK_DUPS, /* DSACK blocks received */ + TCP_NLA_REORD_SEEN, /* reordering events seen */ }; /* for TCP_MD5SIG socket option */ diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index a8ec6564a7ec..250b73ccb644 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -2597,6 +2597,7 @@ int tcp_disconnect(struct sock *sk, int flags) tp->bytes_sent = 0; tp->bytes_retrans = 0; tp->dsack_dups = 0; + tp->reord_seen = 0; /* Clean up fastopen related fields */ tcp_free_fastopen_req(tp); @@ -3207,6 +3208,7 @@ void tcp_get_info(struct sock *sk, struct tcp_info *info) info->tcpi_bytes_sent = tp->bytes_sent; info->tcpi_bytes_retrans = tp->bytes_retrans; info->tcpi_dsack_dups = tp->dsack_dups; + info->tcpi_reord_seen = tp->reord_seen; unlock_sock_fast(sk, slow); } EXPORT_SYMBOL_GPL(tcp_get_info); @@ -3220,7 +3222,7 @@ struct sk_buff *tcp_get_timestamping_opt_stats(const struct sock *sk) u32 rate; stats = alloc_skb(9 * nla_total_size_64bit(sizeof(u64)) + - 8 * nla_total_size(sizeof(u32)) + + 9 * nla_total_size(sizeof(u32)) + 3 * nla_total_size(sizeof(u8)), GFP_ATOMIC); if (!stats) return NULL; @@ -3262,6 +3264,7 @@ struct sk_buff *tcp_get_timestamping_opt_stats(const struct sock *sk) nla_put_u64_64bit(stats, TCP_NLA_BYTES_RETRANS, tp->bytes_retrans, TCP_NLA_PAD); nla_put_u32(stats, TCP_NLA_DSACK_DUPS, tp->dsack_dups); + nla_put_u32(stats, TCP_NLA_REORD_SEEN, tp->reord_seen); return stats; } diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index fbc85ff7d71d..3d6156f07a8d 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -906,8 +906,8 @@ static void tcp_check_sack_reordering(struct sock *sk, const u32 low_seq, sock_net(sk)->ipv4.sysctl_tcp_max_reordering); } - tp->rack.reord = 1; /* This exciting event is worth to be remembered. 8) */ + tp->reord_seen++; NET_INC_STATS(sock_net(sk), ts ? LINUX_MIB_TCPTSREORDER : LINUX_MIB_TCPSACKREORDER); } @@ -1871,6 +1871,7 @@ static void tcp_check_reno_reordering(struct sock *sk, const int addend) tp->reordering = min_t(u32, tp->packets_out + addend, sock_net(sk)->ipv4.sysctl_tcp_max_reordering); + tp->reord_seen++; NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPRENOREORDER); } diff --git a/net/ipv4/tcp_recovery.c b/net/ipv4/tcp_recovery.c index 71593e4400ab..c81aadff769b 100644 --- a/net/ipv4/tcp_recovery.c +++ b/net/ipv4/tcp_recovery.c @@ -25,7 +25,7 @@ static u32 tcp_rack_reo_wnd(const struct sock *sk) { struct tcp_sock *tp = tcp_sk(sk); - if (!tp->rack.reord) { + if (!tp->reord_seen) { /* If reordering has not been observed, be aggressive during * the recovery or starting the recovery by DUPACK threshold. */ -- 2.18.0.345.g5c9ce644c3-goog