tcp_bbr: apply PROBE_RTT cwnd cap even if acked==0
This commit fixes a corner case where TCP BBR would enter PROBE_RTT mode but not reduce its cwnd. If a TCP receiver ACKed less than one full segment, the number of delivered/acked packets was 0, so that bbr_set_cwnd() would short-circuit and exit early, without cutting cwnd to the value we want for PROBE_RTT. The fix is to instead make sure that even when 0 full packets are ACKed, we do apply all the appropriate caps, including the cap that applies in PROBE_RTT mode. Fixes: 0f8782ea ("tcp_bbr: add BBR congestion control") Signed-off-by:Kevin Yang <yyd@google.com> Signed-off-by:
Neal Cardwell <ncardwell@google.com> Reviewed-by:
Yuchung Cheng <ycheng@google.com> Reviewed-by:
Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by:
David S. Miller <davem@davemloft.net>
parent
5490b32d
Please register or sign in to comment