7 files changed, 21 insertions, 49 deletions

diff --git a/include/net/tcp.h b/include/net/tcp.h
index 218235de8963..0366a559afec 100644
--- a/include/net/tcp.h
+++ b/include/net/tcp.h
@@ -685,6 +685,7 @@ extern void tcp_get_allowed_congestion_control(char *buf, size_t len);
 extern int tcp_set_allowed_congestion_control(char *allowed);
 extern int tcp_set_congestion_control(struct sock *sk, const char *name);
 extern void tcp_slow_start(struct tcp_sock *tp);
+extern void tcp_cong_avoid_ai(struct tcp_sock *tp, u32 w);
 
 extern struct tcp_congestion_ops tcp_init_congestion_ops;
 extern u32 tcp_reno_ssthresh(struct sock *sk);
diff --git a/net/ipv4/tcp_bic.c b/net/ipv4/tcp_bic.c
index 7eb7636db0d0..3b53fd1af23f 100644
--- a/net/ipv4/tcp_bic.c
+++ b/net/ipv4/tcp_bic.c
@@ -149,16 +149,7 @@ static void bictcp_cong_avoid(struct sock *sk, u32 ack, u32 in_flight)
                 tcp_slow_start(tp);
         else {
                 bictcp_update(ca, tp->snd_cwnd);
-
-                /* In dangerous area, increase slowly.
-                 * In theory this is tp->snd_cwnd += 1 / tp->snd_cwnd
-                 */
-                if (tp->snd_cwnd_cnt >= ca->cnt) {
-                        if (tp->snd_cwnd < tp->snd_cwnd_clamp)
-                                tp->snd_cwnd++;
-                        tp->snd_cwnd_cnt = 0;
-                } else
-                        tp->snd_cwnd_cnt++;
+                tcp_cong_avoid_ai(tp, ca->cnt);
         }
 
 }
diff --git a/net/ipv4/tcp_cong.c b/net/ipv4/tcp_cong.c
index 4ec5b4e97c4e..e92beb9e55e0 100644
--- a/net/ipv4/tcp_cong.c
+++ b/net/ipv4/tcp_cong.c
@@ -336,6 +336,19 @@ void tcp_slow_start(struct tcp_sock *tp)
 }
 EXPORT_SYMBOL_GPL(tcp_slow_start);
 
+/* In theory this is tp->snd_cwnd += 1 / tp->snd_cwnd (or alternative w) */
+void tcp_cong_avoid_ai(struct tcp_sock *tp, u32 w)
+{
+        if (tp->snd_cwnd_cnt >= w) {
+                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_cong_avoid_ai);
+
 /*
  * TCP Reno congestion control
  * This is special case used for fallback as well.
@@ -365,13 +378,7 @@ void tcp_reno_cong_avoid(struct sock *sk, u32 ack, u32 in_flight)
                                 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++;
+                tcp_cong_avoid_ai(tp, tp->snd_cwnd);
         }
 }
 EXPORT_SYMBOL_GPL(tcp_reno_cong_avoid);
diff --git a/net/ipv4/tcp_cubic.c b/net/ipv4/tcp_cubic.c
index ee467ec40c4f..71d5f2f29fa6 100644
--- a/net/ipv4/tcp_cubic.c
+++ b/net/ipv4/tcp_cubic.c
@@ -294,16 +294,7 @@ static void bictcp_cong_avoid(struct sock *sk, u32 ack, u32 in_flight)
                 tcp_slow_start(tp);
         } else {
                 bictcp_update(ca, tp->snd_cwnd);
-
-                /* In dangerous area, increase slowly.
-                 * In theory this is tp->snd_cwnd += 1 / tp->snd_cwnd
-                 */
-                if (tp->snd_cwnd_cnt >= ca->cnt) {
-                        if (tp->snd_cwnd < tp->snd_cwnd_clamp)
-                                tp->snd_cwnd++;
-                        tp->snd_cwnd_cnt = 0;
-                } else
-                        tp->snd_cwnd_cnt++;
+                tcp_cong_avoid_ai(tp, ca->cnt);
         }
 
 }
diff --git a/net/ipv4/tcp_scalable.c b/net/ipv4/tcp_scalable.c
index 4660b088a8ce..a76513779e2b 100644
--- a/net/ipv4/tcp_scalable.c
+++ b/net/ipv4/tcp_scalable.c
@@ -24,14 +24,8 @@ static void tcp_scalable_cong_avoid(struct sock *sk, u32 ack, u32 in_flight)
 
         if (tp->snd_cwnd <= tp->snd_ssthresh)
                 tcp_slow_start(tp);
-        else {
-                tp->snd_cwnd_cnt++;
-                if (tp->snd_cwnd_cnt > min(tp->snd_cwnd, TCP_SCALABLE_AI_CNT)){
-                        if (tp->snd_cwnd < tp->snd_cwnd_clamp)
-                                tp->snd_cwnd++;
-                        tp->snd_cwnd_cnt = 0;
-                }
-        }
+        else
+                tcp_cong_avoid_ai(tp, min(tp->snd_cwnd, TCP_SCALABLE_AI_CNT));
 }
 
 static u32 tcp_scalable_ssthresh(struct sock *sk)
diff --git a/net/ipv4/tcp_veno.c b/net/ipv4/tcp_veno.c
index d08b2e855c22..e9bbff746488 100644
--- a/net/ipv4/tcp_veno.c
+++ b/net/ipv4/tcp_veno.c
@@ -159,12 +159,7 @@ static void tcp_veno_cong_avoid(struct sock *sk, u32 ack, u32 in_flight)
                                 /* In the "non-congestive state", increase cwnd
                                  *  every rtt.
                                  */
-                                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++;
+                                tcp_cong_avoid_ai(tp, tp->snd_cwnd);
                         } else {
                                 /* In the "congestive state", increase cwnd
                                  * every other rtt.
diff --git a/net/ipv4/tcp_yeah.c b/net/ipv4/tcp_yeah.c
index 9ec843a9bbb2..66b6821b984e 100644
--- a/net/ipv4/tcp_yeah.c
+++ b/net/ipv4/tcp_yeah.c
@@ -94,14 +94,7 @@ static void tcp_yeah_cong_avoid(struct sock *sk, u32 ack, u32 in_flight)
 
         } else {
                 /* Reno */
-
-                if (tp->snd_cwnd_cnt < tp->snd_cwnd)
-                        tp->snd_cwnd_cnt++;
-
-                if (tp->snd_cwnd_cnt >= tp->snd_cwnd) {
-                        tp->snd_cwnd++;
-                        tp->snd_cwnd_cnt = 0;
-                }
+                tcp_cong_avoid_ai(tp, tp->snd_cwnd);
         }
 
         /* The key players are v_vegas.beg_snd_una and v_beg_snd_nxt.