diff options
| author | Yuchung Cheng <[email protected]> | 2014-02-28 16:42:26 -0800 |
|---|---|---|
| committer | David S. Miller <[email protected]> | 2014-03-03 15:33:02 -0500 |
| commit | c84a57113f59486e6688be1cd443b96e3118efa0 (patch) | |
| tree | 5177aed13e8ff6c94ceed13239d824a92e672f71 /include/linux/fpga/fpga-mgr.h | |
| parent | de39d7a4f3693c4247135cbce42716bf2a113577 (diff) | |
tcp: fix bogus RTT on special retransmission
RTT may be bogus with tall loss probe (TLP) when a packet
is retransmitted and latter (s)acked without TCPCB_SACKED_RETRANS flag.
For example, TLP calls __tcp_retransmit_skb() instead of
tcp_retransmit_skb(). The skb timestamps are updated but the sacked
flag is not marked with TCPCB_SACKED_RETRANS. As a result we'll
get bogus RTT in tcp_clean_rtx_queue() or in tcp_sacktag_one() on
spurious retransmission.
The fix is to apply the sticky flag TCP_EVER_RETRANS to enforce Karn's
check on RTT sampling. However this will disable F-RTO if timeout occurs
after TLP, by resetting undo_marker in tcp_enter_loss(). We relax this
check to only if any pending retransmists are still in-flight.
Signed-off-by: Yuchung Cheng <[email protected]>
Acked-by: Eric Dumazet <[email protected]>
Acked-by: Neal Cardwell <[email protected]>
Acked-by: Nandita Dukkipati <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
Diffstat (limited to 'include/linux/fpga/fpga-mgr.h')
0 files changed, 0 insertions, 0 deletions