1 files changed, 24 insertions, 16 deletions

diff --git a/net/ipv4/tcp_cong.c b/net/ipv4/tcp_cong.c
index bbf2d6624e89..c7cc62c8dc12 100644
--- a/net/ipv4/tcp_cong.c
+++ b/net/ipv4/tcp_cong.c
@@ -186,24 +186,32 @@ void tcp_reno_cong_avoid(struct sock *sk, u32 ack, u32 rtt, u32 in_flight,
 {
         struct tcp_sock *tp = tcp_sk(sk);
 
-        if (in_flight < tp->snd_cwnd)
+        if (!tcp_is_cwnd_limited(sk, in_flight))
                 return;
 
-        if (tp->snd_cwnd <= tp->snd_ssthresh) {
-                /* In "safe" area, increase. */
-                if (tp->snd_cwnd < tp->snd_cwnd_clamp)
-                        tp->snd_cwnd++;
-        } else {
-                /* In dangerous area, increase slowly.
-                 * In theory this is tp->snd_cwnd += 1 / tp->snd_cwnd
-                 */
-                if (tp->snd_cwnd_cnt >= tp->snd_cwnd) {
-                        if (tp->snd_cwnd < tp->snd_cwnd_clamp)
-                                tp->snd_cwnd++;
-                        tp->snd_cwnd_cnt = 0;
-                } else
-                        tp->snd_cwnd_cnt++;
-        }
+        /* In "safe" area, increase. */
+        if (tp->snd_cwnd <= tp->snd_ssthresh)
+                tcp_slow_start(tp);
+
+        /* In dangerous area, increase slowly. */
+        else if (sysctl_tcp_abc) {
+                /* RFC3465: Apppriate Byte Count
+                 * increase once for each full cwnd acked
+                 */
+                if (tp->bytes_acked >= tp->snd_cwnd*tp->mss_cache) {
+                        tp->bytes_acked -= tp->snd_cwnd*tp->mss_cache;
+                        if (tp->snd_cwnd < tp->snd_cwnd_clamp)
+                                tp->snd_cwnd++;
+                }
+        } else {
+                /* In theory this is tp->snd_cwnd += 1 / tp->snd_cwnd */
+                if (tp->snd_cwnd_cnt >= tp->snd_cwnd) {
+                        if (tp->snd_cwnd < tp->snd_cwnd_clamp)
+                                tp->snd_cwnd++;
+                        tp->snd_cwnd_cnt = 0;
+                } else
+                        tp->snd_cwnd_cnt++;
+        }
 }
 EXPORT_SYMBOL_GPL(tcp_reno_cong_avoid);