From 1ded3143444ff8a53444b0f736e8cb6a4dc92ace Mon Sep 17 00:00:00 2001
From: Hagen Paul Pfeifer <hagen@jauu.net>
Date: Wed, 30 Nov 2011 12:20:26 +0000
Subject: [PATCH] --- yaml --- r: 278306 b: refs/heads/master c:
 7bc0f28c7a0cd19f40e5a6e4d0a117db9a4e4cd5 h: refs/heads/master v: v3

---
 [refs]                          |  2 +-
 trunk/include/linux/pkt_sched.h |  5 +++++
 trunk/net/sched/sch_netem.c     | 40 +++++++++++++++++++++++++++++++++
 3 files changed, 46 insertions(+), 1 deletion(-)

diff --git a/[refs] b/[refs]
index 2bf2d02d7ea1..8dd1f3ed4aec 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 99d2f47aa9d3ad40daa6ee0770e91b95b71082f0
+refs/heads/master: 7bc0f28c7a0cd19f40e5a6e4d0a117db9a4e4cd5
diff --git a/trunk/include/linux/pkt_sched.h b/trunk/include/linux/pkt_sched.h
index 7281d5acf2f9..fb556dc594d3 100644
--- a/trunk/include/linux/pkt_sched.h
+++ b/trunk/include/linux/pkt_sched.h
@@ -465,6 +465,7 @@ enum {
 	TCA_NETEM_REORDER,
 	TCA_NETEM_CORRUPT,
 	TCA_NETEM_LOSS,
+	TCA_NETEM_RATE,
 	__TCA_NETEM_MAX,
 };
 
@@ -495,6 +496,10 @@ struct tc_netem_corrupt {
 	__u32	correlation;
 };
 
+struct tc_netem_rate {
+	__u32	rate;	/* byte/s */
+};
+
 enum {
 	NETEM_LOSS_UNSPEC,
 	NETEM_LOSS_GI,		/* General Intuitive - 4 state model */
diff --git a/trunk/net/sched/sch_netem.c b/trunk/net/sched/sch_netem.c
index eb3b9a86c6ed..9b7af9f1272f 100644
--- a/trunk/net/sched/sch_netem.c
+++ b/trunk/net/sched/sch_netem.c
@@ -79,6 +79,7 @@ struct netem_sched_data {
 	u32 duplicate;
 	u32 reorder;
 	u32 corrupt;
+	u32 rate;
 
 	struct crndstate {
 		u32 last;
@@ -298,6 +299,11 @@ static psched_tdiff_t tabledist(psched_tdiff_t mu, psched_tdiff_t sigma,
 	return  x / NETEM_DIST_SCALE + (sigma / NETEM_DIST_SCALE) * t + mu;
 }
 
+static psched_time_t packet_len_2_sched_time(unsigned int len, u32 rate)
+{
+	return PSCHED_NS2TICKS((u64)len * NSEC_PER_SEC / rate);
+}
+
 /*
  * Insert one skb into qdisc.
  * Note: parent depends on return value to account for queue length.
@@ -371,6 +377,24 @@ static int netem_enqueue(struct sk_buff *skb, struct Qdisc *sch)
 				  &q->delay_cor, q->delay_dist);
 
 		now = psched_get_time();
+
+		if (q->rate) {
+			struct sk_buff_head *list = &q->qdisc->q;
+
+			delay += packet_len_2_sched_time(skb->len, q->rate);
+
+			if (!skb_queue_empty(list)) {
+				/*
+				 * Last packet in queue is reference point (now).
+				 * First packet in queue is already in flight,
+				 * calculate this time bonus and substract
+				 * from delay.
+				 */
+				delay -= now - netem_skb_cb(skb_peek(list))->time_to_send;
+				now = netem_skb_cb(skb_peek_tail(list))->time_to_send;
+			}
+		}
+
 		cb->time_to_send = now + delay;
 		++q->counter;
 		ret = qdisc_enqueue(skb, q->qdisc);
@@ -535,6 +559,14 @@ static void get_corrupt(struct Qdisc *sch, const struct nlattr *attr)
 	init_crandom(&q->corrupt_cor, r->correlation);
 }
 
+static void get_rate(struct Qdisc *sch, const struct nlattr *attr)
+{
+	struct netem_sched_data *q = qdisc_priv(sch);
+	const struct tc_netem_rate *r = nla_data(attr);
+
+	q->rate = r->rate;
+}
+
 static int get_loss_clg(struct Qdisc *sch, const struct nlattr *attr)
 {
 	struct netem_sched_data *q = qdisc_priv(sch);
@@ -594,6 +626,7 @@ static const struct nla_policy netem_policy[TCA_NETEM_MAX + 1] = {
 	[TCA_NETEM_CORR]	= { .len = sizeof(struct tc_netem_corr) },
 	[TCA_NETEM_REORDER]	= { .len = sizeof(struct tc_netem_reorder) },
 	[TCA_NETEM_CORRUPT]	= { .len = sizeof(struct tc_netem_corrupt) },
+	[TCA_NETEM_RATE]	= { .len = sizeof(struct tc_netem_rate) },
 	[TCA_NETEM_LOSS]	= { .type = NLA_NESTED },
 };
 
@@ -666,6 +699,9 @@ static int netem_change(struct Qdisc *sch, struct nlattr *opt)
 	if (tb[TCA_NETEM_CORRUPT])
 		get_corrupt(sch, tb[TCA_NETEM_CORRUPT]);
 
+	if (tb[TCA_NETEM_RATE])
+		get_rate(sch, tb[TCA_NETEM_RATE]);
+
 	q->loss_model = CLG_RANDOM;
 	if (tb[TCA_NETEM_LOSS])
 		ret = get_loss_clg(sch, tb[TCA_NETEM_LOSS]);
@@ -846,6 +882,7 @@ static int netem_dump(struct Qdisc *sch, struct sk_buff *skb)
 	struct tc_netem_corr cor;
 	struct tc_netem_reorder reorder;
 	struct tc_netem_corrupt corrupt;
+	struct tc_netem_rate rate;
 
 	qopt.latency = q->latency;
 	qopt.jitter = q->jitter;
@@ -868,6 +905,9 @@ static int netem_dump(struct Qdisc *sch, struct sk_buff *skb)
 	corrupt.correlation = q->corrupt_cor.rho;
 	NLA_PUT(skb, TCA_NETEM_CORRUPT, sizeof(corrupt), &corrupt);
 
+	rate.rate = q->rate;
+	NLA_PUT(skb, TCA_NETEM_RATE, sizeof(rate), &rate);
+
 	if (dump_loss_model(q, skb) != 0)
 		goto nla_put_failure;