linux 2.6.16.38 w/ vs2.0.3-rc1
[linux-2.6.git] / net / ipv4 / tcp_highspeed.c
index fa3e1aa..e0e9d13 100644 (file)
@@ -6,6 +6,7 @@
  * John Heffner <jheffner@psc.edu>
  */
 
+#include <linux/config.h>
 #include <linux/module.h>
 #include <net/tcp.h>
 
@@ -97,10 +98,6 @@ struct hstcp {
        u32     ai;
 };
 
-static int max_ssthresh = 100;
-module_param(max_ssthresh, int, 0644);
-MODULE_PARM_DESC(max_ssthresh, "limited slow start threshold (RFC3742)");
-
 static void hstcp_init(struct sock *sk)
 {
        struct tcp_sock *tp = tcp_sk(sk);
@@ -122,46 +119,26 @@ static void hstcp_cong_avoid(struct sock *sk, u32 adk, u32 rtt,
        if (!tcp_is_cwnd_limited(sk, in_flight))
                return;
 
-       if (tp->snd_cwnd <= tp->snd_ssthresh) {
-               /* RFC3742: limited slow start
-                * the window is increased by 1/K MSS for each arriving ACK,
-                * for K = int(cwnd/(0.5 max_ssthresh))
-                */
-               if (max_ssthresh > 0 && tp->snd_cwnd > max_ssthresh) {
-                       u32 k = max(tp->snd_cwnd / (max_ssthresh >> 1), 1U);
-                       if (++tp->snd_cwnd_cnt >= k) {
-                               if (tp->snd_cwnd < tp->snd_cwnd_clamp)
-                                       tp->snd_cwnd++;
-                               tp->snd_cwnd_cnt = 0;
-                       }
-               } else {
-                       if (tp->snd_cwnd < tp->snd_cwnd_clamp)
-                               tp->snd_cwnd++;
-               }
-       } else {
-               /* Update AIMD parameters.
-                *
-                * We want to guarantee that:
-                *     hstcp_aimd_vals[ca->ai-1].cwnd <
-                *     snd_cwnd <=
-                *     hstcp_aimd_vals[ca->ai].cwnd
-                */
+       if (tp->snd_cwnd <= tp->snd_ssthresh)
+               tcp_slow_start(tp);
+       else {
+               /* Update AIMD parameters */
                if (tp->snd_cwnd > hstcp_aimd_vals[ca->ai].cwnd) {
                        while (tp->snd_cwnd > hstcp_aimd_vals[ca->ai].cwnd &&
                               ca->ai < HSTCP_AIMD_MAX - 1)
                                ca->ai++;
-               } else if (ca->ai && tp->snd_cwnd <= hstcp_aimd_vals[ca->ai-1].cwnd) {
-                       while (ca->ai && tp->snd_cwnd <= hstcp_aimd_vals[ca->ai-1].cwnd)
+               } else if (tp->snd_cwnd < hstcp_aimd_vals[ca->ai].cwnd) {
+                       while (tp->snd_cwnd > hstcp_aimd_vals[ca->ai].cwnd &&
+                              ca->ai > 0)
                                ca->ai--;
                }
 
                /* Do additive increase */
                if (tp->snd_cwnd < tp->snd_cwnd_clamp) {
-                       /* cwnd = cwnd + a(w) / cwnd */
-                       tp->snd_cwnd_cnt += ca->ai + 1;
+                       tp->snd_cwnd_cnt += ca->ai;
                        if (tp->snd_cwnd_cnt >= tp->snd_cwnd) {
-                               tp->snd_cwnd_cnt -= tp->snd_cwnd;
                                tp->snd_cwnd++;
+                               tp->snd_cwnd_cnt -= tp->snd_cwnd;
                        }
                }
        }