1 files changed, 4 insertions, 0 deletions

diff --git a/net/ipv4/tcp_bbr.c b/net/ipv4/tcp_bbr.c
index 58e2f479ffb4..4bfff3c87e8e 100644
--- a/net/ipv4/tcp_bbr.c
+++ b/net/ipv4/tcp_bbr.c
@@ -354,6 +354,10 @@ static u32 bbr_target_cwnd(struct sock *sk, u32 bw, int gain)
         /* Reduce delayed ACKs by rounding up cwnd to the next even number. */
         cwnd = (cwnd + 1) & ~1U;
 
+        /* Ensure gain cycling gets inflight above BDP even for small BDPs. */
+        if (bbr->mode == BBR_PROBE_BW && gain > BBR_UNIT)
+                cwnd += 2;
+
         return cwnd;
 }