aboutsummaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorIlpo Järvinen <ilpo.jarvinen@helsinki.fi>2008-09-20 21:26:22 -0700
committerDavid S. Miller <davem@davemloft.net>2008-09-20 21:26:22 -0700
commit618d9f25548ba6fc3a9cd2ce5cd56f4f015b0635 (patch)
treef04a91ec4aac1fc4bcb0b8204a8ff64c3844e6de
parent90638a04ad8484b6b6c567656fb3f6d0689e23da (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.c12
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