[TCP] tcp_highspeed: Fix problem observed by Xiaoliang (David) Wei
When snd_cwnd is smaller than 38 and the connection is in
congestion avoidance phase (snd_cwnd > snd_ssthresh), the snd_cwnd
seems to stop growing.
The additive increase was confused because C array's are 0 based.
Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/tcp_highspeed.c b/net/ipv4/tcp_highspeed.c
index b72fa55..ba7c63c 100644
--- a/net/ipv4/tcp_highspeed.c
+++ b/net/ipv4/tcp_highspeed.c
@@ -135,7 +135,8 @@
/* Do additive increase */
if (tp->snd_cwnd < tp->snd_cwnd_clamp) {
- tp->snd_cwnd_cnt += ca->ai;
+ /* cwnd = cwnd + a(w) / cwnd */
+ tp->snd_cwnd_cnt += ca->ai + 1;
if (tp->snd_cwnd_cnt >= tp->snd_cwnd) {
tp->snd_cwnd_cnt -= tp->snd_cwnd;
tp->snd_cwnd++;
