diff options
| author | Eric Dumazet <edumazet@google.com> | 2021-03-11 12:35:05 -0800 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2021-03-11 18:35:31 -0800 |
| commit | a7abf3cd76e1e190a2c22afe5ffd0f695c7641b0 (patch) | |
| tree | 2b70863783d21ad6b50503bf27ca2e5a54555b8b /net/ipv4/tcp_input.c | |
| parent | f4dae54e486d528d4dd98df116e7a522bbf12667 (diff) | |
| download | linux-a7abf3cd76e1e190a2c22afe5ffd0f695c7641b0.tar.gz | |
tcp: consider using standard rtx logic in tcp_rcv_fastopen_synack()
Jakub reported Data included in a Fastopen SYN that had to be
retransmit would have to wait for an RTO if TX completions are slow,
even with prior fix.
This is because tcp_rcv_fastopen_synack() does not use standard
rtx logic, meaning TSQ handler exits early in tcp_tsq_write()
because tp->lost_out == tp->retrans_out
Lets make tcp_rcv_fastopen_synack() use standard rtx logic,
by using tcp_mark_skb_lost() on the skb thats needs to be
sent again.
Not this raised a warning in tcp_fastretrans_alert() during my tests
since we consider the data not being aknowledged
by the receiver does not mean packet was lost on the network.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Jakub Kicinski <kuba@kernel.org>
Cc: Neal Cardwell <ncardwell@google.com>
Cc: Yuchung Cheng <ycheng@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 | 10 |
1 files changed, 4 insertions, 6 deletions
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index 69a545db80d2e..4cf4dd532d1c6 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -2914,7 +2914,7 @@ static void tcp_fastretrans_alert(struct sock *sk, const u32 prior_snd_una, /* D. Check state exit conditions. State can be terminated * when high_seq is ACKed. */ if (icsk->icsk_ca_state == TCP_CA_Open) { - WARN_ON(tp->retrans_out != 0); + WARN_ON(tp->retrans_out != 0 && !tp->syn_data); tp->retrans_stamp = 0; } else if (!before(tp->snd_una, tp->high_seq)) { switch (icsk->icsk_ca_state) { @@ -5994,11 +5994,9 @@ static bool tcp_rcv_fastopen_synack(struct sock *sk, struct sk_buff *synack, tp->fastopen_client_fail = TFO_SYN_RETRANSMITTED; else tp->fastopen_client_fail = TFO_DATA_NOT_ACKED; - skb_rbtree_walk_from(data) { - if (__tcp_retransmit_skb(sk, data, 1)) - break; - } - tcp_rearm_rto(sk); + skb_rbtree_walk_from(data) + tcp_mark_skb_lost(sk, data); + tcp_xmit_retransmit_queue(sk); NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPFASTOPENACTIVEFAIL); return true; |