diff options
| author | Francis Yan <francisyyan@gmail.com> | 2016-11-27 23:07:14 -0800 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2016-11-30 10:04:24 -0500 |
| commit | 0f87230d1a6c253681550c6064715d06a32be73d (patch) | |
| tree | 592c761f9b1b2b6e524e8fc87a43db69ded5e4a8 /net/ipv4/tcp_input.c | |
| parent | 05b055e89121394058c75dc354e9a46e1e765579 (diff) | |
tcp: instrument how long TCP is busy sending
This patch measures TCP busy time, which is defined as the period
of time when sender has data (or FIN) to send. The time starts when
data is buffered and stops when the write queue is flushed by ACKs
or error events.
Note the busy time does not include SYN time, unless data is
included in SYN (i.e. Fast Open). It does include FIN time even
if the FIN carries no payload. Excluding pure FIN is possible but
would incur one additional test in the fast path, which may not
be worth it.
Signed-off-by: Francis Yan <francisyyan@gmail.com>
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/ipv4/tcp_input.c')
| -rw-r--r-- | net/ipv4/tcp_input.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index 22e6a2097ff6..a5d172761610 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -3178,6 +3178,9 @@ static int tcp_clean_rtx_queue(struct sock *sk, int prior_fackets, tp->lost_skb_hint = NULL; } + if (!skb) + tcp_chrono_stop(sk, TCP_CHRONO_BUSY); + if (likely(between(tp->snd_up, prior_snd_una, tp->snd_una))) tp->snd_up = tp->snd_una; |