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| author |   Martin KaFai Lau <kafai@fb.com> | 2016-03-14 10:52:15 -0700 |
|---|---|---|
| committer |   David S. Miller <davem@davemloft.net> | 2016-03-14 14:55:26 -0400 |
| commit | a44d6eacdaf56f74fad699af7f4925a5f5ac0e7f (patch) | |
| tree | b692d2dae4e19397ceeab4559fed2d1c86ba9491 /net/ipv4/tcp_fastopen.c | |
| parent | vmxnet3: fix lock imbalance in vmxnet3_tq_xmit() (diff) | |
| download | linux-dev-a44d6eacdaf56f74fad699af7f4925a5f5ac0e7f.tar.xz linux-dev-a44d6eacdaf56f74fad699af7f4925a5f5ac0e7f.zip | |
tcp: Add RFC4898 tcpEStatsPerfDataSegsOut/In
Per RFC4898, they count segments sent/received
containing a positive length data segment (that includes
retransmission segments carrying data). Unlike
tcpi_segs_out/in, tcpi_data_segs_out/in excludes segments
carrying no data (e.g. pure ack).
The patch also updates the segs_in in tcp_fastopen_add_skb()
so that segs_in >= data_segs_in property is kept.
Together with retransmission data, tcpi_data_segs_out
gives a better signal on the rxmit rate.
v6: Rebase on the latest net-next
v5: Eric pointed out that checking skb->len is still needed in
tcp_fastopen_add_skb() because skb can carry a FIN without data.
Hence, instead of open coding segs_in and data_segs_in, tcp_segs_in()
helper is used. Comment is added to the fastopen case to explain why
segs_in has to be reset and tcp_segs_in() has to be called before
__skb_pull().
v4: Add comment to the changes in tcp_fastopen_add_skb()
and also add remark on this case in the commit message.
v3: Add const modifier to the skb parameter in tcp_segs_in()
v2: Rework based on recent fix by Eric:
commit a9d99ce28ed3 ("tcp: fix tcpi_segs_in after connection establishment")
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Cc: Chris Rapier <rapier@psc.edu>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Marcelo Ricardo Leitner <mleitner@redhat.com>
Cc: Neal Cardwell <ncardwell@google.com>
Cc: Yuchung Cheng <ycheng@google.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to '')
| -rw-r--r-- | net/ipv4/tcp_fastopen.c | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/net/ipv4/tcp_fastopen.c b/net/ipv4/tcp_fastopen.c index fdb286ddba04..4fc0061bebf4 100644 --- a/net/ipv4/tcp_fastopen.c +++ b/net/ipv4/tcp_fastopen.c @@ -140,6 +140,14 @@ void tcp_fastopen_add_skb(struct sock *sk, struct sk_buff *skb) return; skb_dst_drop(skb); + /* segs_in has been initialized to 1 in tcp_create_openreq_child(). + * Hence, reset segs_in to 0 before calling tcp_segs_in() + * to avoid double counting. Also, tcp_segs_in() expects + * skb->len to include the tcp_hdrlen. Hence, it should + * be called before __skb_pull(). + */ + tp->segs_in = 0; + tcp_segs_in(tp, skb); __skb_pull(skb, tcp_hdrlen(skb)); skb_set_owner_r(skb, sk); |