[TCP]: Extend reordering detection to cover CA_Loss partially
commitf577111302677e6d1448475821cc19ba8835f60e
authorIlpo Järvinen <ilpo.jarvinen@helsinki.fi>
Fri, 16 Nov 2007 03:35:11 +0000 (15 19:35 -0800)
committerDavid S. Miller <davem@davemloft.net>
Mon, 28 Jan 2008 22:54:02 +0000 (28 14:54 -0800)
tree4c5f5f0081bb0843a589fcae86ec6dc13dee3526
parentb9d86585dc6c9265aa373c7036458fe8aa7627c6
[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>
net/ipv4/tcp_input.c