From be0d935ebfe59130b393bc442e1801e523b43fc6 Mon Sep 17 00:00:00 2001
From: Pengcheng Yang <yangpc@wangsu.com>
Date: Mon, 16 Mar 2020 14:35:07 +0800
Subject: [PATCH] tcp: fix stretch ACK bugs in BIC
Changes BIC to properly handle stretch ACKs in additive
increase mode by passing in the count of ACKed packets
to tcp_cong_avoid_ai().
Signed-off-by: Pengcheng Yang <yangpc@wangsu.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
net/ipv4/tcp_bic.c | 11 ++++++-----
1 file changed, 6 insertions(+), 5 deletions(-)
diff --git a/net/ipv4/tcp_bic.c b/net/ipv4/tcp_bic.c
index 645cc3009e64..f5f588b1f6e9 100644
--- a/net/ipv4/tcp_bic.c
+++ b/net/ipv4/tcp_bic.c
@@ -145,12 +145,13 @@ static void bictcp_cong_avoid(struct sock *sk, u32 ack, u32 acked)
if (!tcp_is_cwnd_limited(sk))
return;
- if (tcp_in_slow_start(tp))
- tcp_slow_start(tp, acked);
- else {
- bictcp_update(ca, tp->snd_cwnd);
- tcp_cong_avoid_ai(tp, ca->cnt, 1);
+ if (tcp_in_slow_start(tp)) {
+ acked = tcp_slow_start(tp, acked);
+ if (!acked)
+ return;
}
+ bictcp_update(ca, tp->snd_cwnd);
+ tcp_cong_avoid_ai(tp, ca->cnt, acked);
}
/*