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-rw-r--r--net/sched/sch_netem.c68
1 files changed, 68 insertions, 0 deletions
diff --git a/net/sched/sch_netem.c b/net/sched/sch_netem.c
index eb3b9a86c6ed..1fa2f903d221 100644
--- a/net/sched/sch_netem.c
+++ b/net/sched/sch_netem.c
@@ -22,6 +22,7 @@
#include <linux/skbuff.h>
#include <linux/vmalloc.h>
#include <linux/rtnetlink.h>
+#include <linux/reciprocal_div.h>
#include <net/netlink.h>
#include <net/pkt_sched.h>
@@ -79,6 +80,11 @@ struct netem_sched_data {
u32 duplicate;
u32 reorder;
u32 corrupt;
+ u32 rate;
+ s32 packet_overhead;
+ u32 cell_size;
+ u32 cell_size_reciprocal;
+ s32 cell_overhead;
struct crndstate {
u32 last;
@@ -298,6 +304,26 @@ 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, struct netem_sched_data *q)
+{
+ u64 ticks;
+
+ len += q->packet_overhead;
+
+ if (q->cell_size) {
+ u32 cells = reciprocal_divide(len, q->cell_size_reciprocal);
+
+ if (len > cells * q->cell_size) /* extra cell needed for remainder */
+ cells++;
+ len = cells * (q->cell_size + q->cell_overhead);
+ }
+
+ ticks = (u64)len * NSEC_PER_SEC;
+
+ do_div(ticks, q->rate);
+ return PSCHED_NS2TICKS(ticks);
+}
+
/*
* Insert one skb into qdisc.
* Note: parent depends on return value to account for queue length.
@@ -371,6 +397,24 @@ 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);
+
+ 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 +579,19 @@ 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;
+ q->packet_overhead = r->packet_overhead;
+ q->cell_size = r->cell_size;
+ if (q->cell_size)
+ q->cell_size_reciprocal = reciprocal_value(q->cell_size);
+ q->cell_overhead = r->cell_overhead;
+}
+
static int get_loss_clg(struct Qdisc *sch, const struct nlattr *attr)
{
struct netem_sched_data *q = qdisc_priv(sch);
@@ -594,6 +651,7 @@ 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 +724,9 @@ 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 +907,7 @@ 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 +930,12 @@ 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;
+ rate.packet_overhead = q->packet_overhead;
+ rate.cell_size = q->cell_size;
+ rate.cell_overhead = q->cell_overhead;
+ NLA_PUT(skb, TCA_NETEM_RATE, sizeof(rate), &rate);
+
if (dump_loss_model(q, skb) != 0)
goto nla_put_failure;