From 8f7baad7f03543451af27f5380fc816b008aa1f2 Mon Sep 17 00:00:00 2001 From: Thomas Higdon Date: Fri, 13 Sep 2019 23:23:35 +0000 Subject: tcp: Add snd_wnd to TCP_INFO Neal Cardwell mentioned that snd_wnd would be useful for diagnosing TCP performance problems -- > (1) Usually when we're diagnosing TCP performance problems, we do so > from the sender, since the sender makes most of the > performance-critical decisions (cwnd, pacing, TSO size, TSQ, etc). > From the sender-side the thing that would be most useful is to see > tp->snd_wnd, the receive window that the receiver has advertised to > the sender. This serves the purpose of adding an additional __u32 to avoid the would-be hole caused by the addition of the tcpi_rcvi_ooopack field. Signed-off-by: Thomas Higdon Acked-by: Yuchung Cheng Acked-by: Neal Cardwell Acked-by: Soheil Hassas Yeganeh Signed-off-by: David S. Miller --- include/uapi/linux/tcp.h | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'include/uapi/linux/tcp.h') diff --git a/include/uapi/linux/tcp.h b/include/uapi/linux/tcp.h index 20237987ccc8..81e697978e8b 100644 --- a/include/uapi/linux/tcp.h +++ b/include/uapi/linux/tcp.h @@ -272,6 +272,10 @@ struct tcp_info { __u32 tcpi_reord_seen; /* reordering events seen */ __u32 tcpi_rcv_ooopack; /* Out-of-order packets received */ + + __u32 tcpi_snd_wnd; /* peer's advertised receive window after + * scaling (bytes) + */ }; /* netlink attributes types for SCM_TIMESTAMPING_OPT_STATS */ -- cgit v1.2.3