From mboxrd@z Thu Jan 1 00:00:00 1970 From: Yafang Shao Subject: [PATCH net-next] tcp: expose sk_state in tcp_retransmit_skb tracepoint Date: Mon, 24 Sep 2018 03:49:01 +0800 Message-ID: <1537732141-22468-1-git-send-email-laoar.shao@gmail.com> Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org, Yafang Shao To: edumazet@google.com, davem@davemloft.net Return-path: Sender: linux-kernel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org With sk_state, we can know whether this connection is in SYN_SENT state or ESTBLISHED state. The reason to distinguish between these two scenario is that the retransmission in ESTABLISHED state always mean network congestion while in SYN_SENT state it always mean server issue, i.e. the syn packet is dropped due to syn backlog queue full. PS: SYNACK retransmission is traced in tcp_retransmit_synack tracepoint. Signed-off-by: Yafang Shao --- include/trace/events/tcp.h | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/include/trace/events/tcp.h b/include/trace/events/tcp.h index ac55b32..2bc9960 100644 --- a/include/trace/events/tcp.h +++ b/include/trace/events/tcp.h @@ -56,6 +56,7 @@ TP_STRUCT__entry( __field(const void *, skbaddr) __field(const void *, skaddr) + __field(int, state) __field(__u16, sport) __field(__u16, dport) __array(__u8, saddr, 4) @@ -70,6 +71,7 @@ __entry->skbaddr = skb; __entry->skaddr = sk; + __entry->state = sk->sk_state; __entry->sport = ntohs(inet->inet_sport); __entry->dport = ntohs(inet->inet_dport); @@ -84,9 +86,10 @@ sk->sk_v6_rcv_saddr, sk->sk_v6_daddr); ), - TP_printk("sport=%hu dport=%hu saddr=%pI4 daddr=%pI4 saddrv6=%pI6c daddrv6=%pI6c", + TP_printk("sport=%hu dport=%hu saddr=%pI4 daddr=%pI4 saddrv6=%pI6c daddrv6=%pI6c state=%s\n", __entry->sport, __entry->dport, __entry->saddr, __entry->daddr, - __entry->saddr_v6, __entry->daddr_v6) + __entry->saddr_v6, __entry->daddr_v6, + show_tcp_state_name(__entry->state)) ); DEFINE_EVENT(tcp_event_sk_skb, tcp_retransmit_skb, -- 1.8.3.1