summaryrefslogtreecommitdiff
path: root/net/ipv4/tcp_scalable.c
diff options
context:
space:
mode:
authorThomas Gleixner <tglx@tglx.tec.linutronix.de>2005-06-26 23:20:36 +0200
committerThomas Gleixner <tglx@mtd.linutronix.de>2005-06-26 23:20:36 +0200
commit7ca6448dbfb398bba36eda3c01bc14b86c3675be (patch)
tree82d934ebf07f22a2c64c3b6d82ec24082878b43a /net/ipv4/tcp_scalable.c
parentf1f67a9874f1a4bba1adff6d694aa52e5f52ff1a (diff)
parent7d681b23d6cc14a8c026ea6756242cb522cbbcae (diff)
Merge with rsync://fileserver/linux
Update to Linus latest
Diffstat (limited to 'net/ipv4/tcp_scalable.c')
-rw-r--r--net/ipv4/tcp_scalable.c68
1 files changed, 68 insertions, 0 deletions
diff --git a/net/ipv4/tcp_scalable.c b/net/ipv4/tcp_scalable.c
new file mode 100644
index 000000000000..70e108e15c71
--- /dev/null
+++ b/net/ipv4/tcp_scalable.c
@@ -0,0 +1,68 @@
+/* Tom Kelly's Scalable TCP
+ *
+ * See htt://www-lce.eng.cam.ac.uk/~ctk21/scalable/
+ *
+ * John Heffner <jheffner@sc.edu>
+ */
+
+#include <linux/config.h>
+#include <linux/module.h>
+#include <net/tcp.h>
+
+/* These factors derived from the recommended values in the aer:
+ * .01 and and 7/8. We use 50 instead of 100 to account for
+ * delayed ack.
+ */
+#define TCP_SCALABLE_AI_CNT 50U
+#define TCP_SCALABLE_MD_SCALE 3
+
+static void tcp_scalable_cong_avoid(struct tcp_sock *tp, u32 ack, u32 rtt,
+ u32 in_flight, int flag)
+{
+ if (in_flight < tp->snd_cwnd)
+ return;
+
+ if (tp->snd_cwnd <= tp->snd_ssthresh) {
+ tp->snd_cwnd++;
+ } else {
+ tp->snd_cwnd_cnt++;
+ if (tp->snd_cwnd_cnt > min(tp->snd_cwnd, TCP_SCALABLE_AI_CNT)){
+ tp->snd_cwnd++;
+ tp->snd_cwnd_cnt = 0;
+ }
+ }
+ tp->snd_cwnd = min_t(u32, tp->snd_cwnd, tp->snd_cwnd_clamp);
+ tp->snd_cwnd_stamp = tcp_time_stamp;
+}
+
+static u32 tcp_scalable_ssthresh(struct tcp_sock *tp)
+{
+ return max(tp->snd_cwnd - (tp->snd_cwnd>>TCP_SCALABLE_MD_SCALE), 2U);
+}
+
+
+static struct tcp_congestion_ops tcp_scalable = {
+ .ssthresh = tcp_scalable_ssthresh,
+ .cong_avoid = tcp_scalable_cong_avoid,
+ .min_cwnd = tcp_reno_min_cwnd,
+
+ .owner = THIS_MODULE,
+ .name = "scalable",
+};
+
+static int __init tcp_scalable_register(void)
+{
+ return tcp_register_congestion_control(&tcp_scalable);
+}
+
+static void __exit tcp_scalable_unregister(void)
+{
+ tcp_unregister_congestion_control(&tcp_scalable);
+}
+
+module_init(tcp_scalable_register);
+module_exit(tcp_scalable_unregister);
+
+MODULE_AUTHOR("John Heffner");
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Scalable TCP");