diff options
| author | Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> | 2008-09-20 21:26:22 -0700 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2008-09-20 21:26:22 -0700 |
| commit | 618d9f25548ba6fc3a9cd2ce5cd56f4f015b0635 (patch) | |
| tree | f04a91ec4aac1fc4bcb0b8204a8ff64c3844e6de | |
| parent | 90638a04ad8484b6b6c567656fb3f6d0689e23da (diff) | |
tcp: back retransmit_high when it over-estimated
If lost skb is sacked, we might have nothing to retransmit
as high as the retransmit_high is pointing to, so place
it lower to avoid unnecessary walking.
This is mainly for the case where high L'ed skbs gets sacked.
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | net/ipv4/tcp_output.c | 12 |
1 files changed, 10 insertions, 2 deletions
diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c index 239cea7b6c0..8f9793a37b6 100644 --- a/net/ipv4/tcp_output.c +++ b/net/ipv4/tcp_output.c @@ -2035,16 +2035,22 @@ void tcp_xmit_retransmit_queue(struct sock *sk) struct tcp_sock *tp = tcp_sk(sk); struct sk_buff *skb; struct sk_buff *hole = NULL; + u32 last_lost; int mib_idx; int fwd_rexmitting = 0; if (!tp->lost_out) tp->retransmit_high = tp->snd_una; - if (tp->retransmit_skb_hint) + if (tp->retransmit_skb_hint) { skb = tp->retransmit_skb_hint; - else + last_lost = TCP_SKB_CB(skb)->end_seq; + if (after(last_lost, tp->retransmit_high)) + last_lost = tp->retransmit_high; + } else { skb = tcp_write_queue_head(sk); + last_lost = tp->snd_una; + } /* First pass: retransmit lost packets. */ tcp_for_write_queue_from(skb, sk) { @@ -2073,6 +2079,7 @@ begin_fwd: mib_idx = LINUX_MIB_TCPFORWARDRETRANS; } else if (!before(TCP_SKB_CB(skb)->seq, tp->retransmit_high)) { + tp->retransmit_high = last_lost; if (!tcp_can_forward_retransmit(sk)) break; /* Backtrack if necessary to non-L'ed skb */ @@ -2089,6 +2096,7 @@ begin_fwd: continue; } else { + last_lost = TCP_SKB_CB(skb)->end_seq; if (icsk->icsk_ca_state != TCP_CA_Loss) mib_idx = LINUX_MIB_TCPFASTRETRANS; else |