diff options
| author | Yuchung Cheng <ycheng@google.com> | 2017-01-12 22:11:34 -0800 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2017-01-13 22:37:16 -0500 |
| commit | 1d0833df594390876647c54c2c88069d29059665 (patch) | |
| tree | abd620968abad8f56e132a108b5bf354eb0d3b54 /include | |
| parent | 57dde7f70de34d4251f291c9eac7ad920aaf56b2 (diff) | |
tcp: use sequence to break TS ties for RACK loss detection
The packets inside a jumbo skb (e.g., TSO) share the same skb
timestamp, even though they are sent sequentially on the wire. Since
RACK is based on time, it can not detect some packets inside the
same skb are lost. However, we can leverage the packet sequence
numbers as extended timestamps to detect losses. Therefore, when
RACK timestamp is identical to skb's timestamp (i.e., one of the
packets of the skb is acked or sacked), we use the sequence numbers
of the acked and unacked packets to break ties.
We can use the same sequence logic to advance RACK xmit time as
well to detect more losses and avoid timeout.
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'include')
| -rw-r--r-- | include/linux/tcp.h | 1 | ||||
| -rw-r--r-- | include/net/tcp.h | 2 |
2 files changed, 2 insertions, 1 deletions
diff --git a/include/linux/tcp.h b/include/linux/tcp.h index 1255c592719c..970d5f00589f 100644 --- a/include/linux/tcp.h +++ b/include/linux/tcp.h @@ -208,6 +208,7 @@ struct tcp_sock { struct tcp_rack { struct skb_mstamp mstamp; /* (Re)sent time of the skb */ u32 rtt_us; /* Associated RTT */ + u32 end_seq; /* Ending TCP sequence of the skb */ u8 advanced; /* mstamp advanced since last lost marking */ u8 reord; /* reordering detected */ } rack; diff --git a/include/net/tcp.h b/include/net/tcp.h index 64fcdeb3358b..5fb1e75a32a9 100644 --- a/include/net/tcp.h +++ b/include/net/tcp.h @@ -1867,7 +1867,7 @@ extern int sysctl_tcp_recovery; #define TCP_RACK_LOST_RETRANS 0x1 extern void tcp_rack_mark_lost(struct sock *sk, const struct skb_mstamp *now); -extern void tcp_rack_advance(struct tcp_sock *tp, u8 sacked, +extern void tcp_rack_advance(struct tcp_sock *tp, u8 sacked, u32 end_seq, const struct skb_mstamp *xmit_time, const struct skb_mstamp *ack_time); extern void tcp_rack_reo_timeout(struct sock *sk); |