Re: [PATCH net-next] tcp: add tcpi_segs_in and tcpi_segs_out to tcp_info

[David Miller <davem@davemloft.net>]

From: Eric Dumazet <eric.dumazet@gmail.com>
Date: Wed, 20 May 2015 16:35:41 -0700

> From: Marcelo Ricardo Leitner <mleitner@redhat.com>
> 
> This patch tracks the total number of inbound and outbound segments on a
> TCP socket. One may use this number to have an idea on connection
> quality when compared against the retransmissions.
> 
> RFC4898 named these : tcpEStatsPerfSegsIn and tcpEStatsPerfSegsOut
> 
> These are a 32bit field each and can be fetched both from TCP_INFO
> getsockopt() if one has a handle on a TCP socket, or from inet_diag
> netlink facility (iproute2/ss patch will follow)
> 
> Note that tp->segs_out was placed near tp->snd_nxt for good data
> locality and minimal performance impact, while tp->segs_in was placed
> near tp->bytes_received for the same reason.
> 
> Join work with Eric Dumazet.
> 
> Note that received SYN are accounted on the listener, but sent SYNACK 
> are not accounted.
> 
> Signed-off-by: Marcelo Ricardo Leitner <mleitner@redhat.com>
> Signed-off-by: Eric Dumazet <edumazet@google.com>

Applied to net-next, thanks.