diff options
authorNeal Cardwell <ncardwell@google.com>2017-12-07 12:43:32 -0500
committerDavid S. Miller <davem@davemloft.net>2017-12-08 13:27:43 -0500
commit600647d467c6d04b3954b41a6ee1795b5ae00550 (patch)
parent2f6c498e4f15d27852c04ed46d804a39137ba364 (diff)
tcp_bbr: reset long-term bandwidth sampling on loss recovery undo
Fix BBR so that upon notification of a loss recovery undo BBR resets long-term bandwidth sampling. Under high reordering, reordering events can be interpreted as loss. If the reordering and spurious loss estimates are high enough, this can cause BBR to spuriously estimate that we are seeing loss rates high enough to trigger long-term bandwidth estimation. To avoid that problem, this commit resets long-term bandwidth sampling on loss recovery undo events. Signed-off-by: Neal Cardwell <ncardwell@google.com> Reviewed-by: Yuchung Cheng <ycheng@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
1 files changed, 1 insertions, 0 deletions
diff --git a/net/ipv4/tcp_bbr.c b/net/ipv4/tcp_bbr.c
index ab3ff14ea7f7..8322f26e770e 100644
--- a/net/ipv4/tcp_bbr.c
+++ b/net/ipv4/tcp_bbr.c
@@ -878,6 +878,7 @@ static u32 bbr_undo_cwnd(struct sock *sk)
bbr->full_bw = 0; /* spurious slow-down; reset full pipe detection */
bbr->full_bw_cnt = 0;
+ bbr_reset_lt_bw_sampling(sk);
return tcp_sk(sk)->snd_cwnd;