summaryrefslogtreecommitdiff
path: root/net
diff options
context:
space:
mode:
authorIlpo Järvinen <ilpo.jarvinen@helsinki.fi>2007-11-16 03:35:11 (GMT)
committerDavid S. Miller <davem@davemloft.net>2008-01-28 22:54:02 (GMT)
commitf577111302677e6d1448475821cc19ba8835f60e (patch)
tree4c5f5f0081bb0843a589fcae86ec6dc13dee3526 /net
parentb9d86585dc6c9265aa373c7036458fe8aa7627c6 (diff)
downloadlinux-f577111302677e6d1448475821cc19ba8835f60e.tar.xz
[TCP]: Extend reordering detection to cover CA_Loss partially
This implements more accurately what is stated in sacktag's overall comment: "Both of these heuristics are not used in Loss state, when we cannot account for retransmits accurately." When CA_Loss state is entered, the state changer ensures that undo_marker is only set if no TCPCB_RETRANS skbs were found, thus having non-zero undo_marker in CA_Loss basically tells that the R-bits still accurately reflect the current state of TCP. Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net')
-rw-r--r--net/ipv4/tcp_input.c3
1 files changed, 2 insertions, 1 deletions
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index 901240f..26713e5d 100644
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -1511,7 +1511,8 @@ tcp_sacktag_write_queue(struct sock *sk, struct sk_buff *ack_skb, u32 prior_snd_
tcp_verify_left_out(tp);
- if ((reord < tp->fackets_out) && icsk->icsk_ca_state != TCP_CA_Loss &&
+ if ((reord < tp->fackets_out) &&
+ ((icsk->icsk_ca_state != TCP_CA_Loss) || tp->undo_marker) &&
(!tp->frto_highmark || after(tp->snd_una, tp->frto_highmark)))
tcp_update_reordering(sk, tp->fackets_out - reord, 0);