diff options
-rw-r--r-- | include/linux/pkt_sched.h | 3 | ||||
-rw-r--r-- | net/sched/sch_netem.c | 33 |
2 files changed, 32 insertions, 4 deletions
diff --git a/include/linux/pkt_sched.h b/include/linux/pkt_sched.h index 8786ea7..8daced3 100644 --- a/include/linux/pkt_sched.h +++ b/include/linux/pkt_sched.h @@ -502,6 +502,9 @@ struct tc_netem_corrupt { struct tc_netem_rate { __u32 rate; /* byte/s */ + __s32 packet_overhead; + __u32 cell_size; + __s32 cell_overhead; }; enum { diff --git a/net/sched/sch_netem.c b/net/sched/sch_netem.c index 3bfd733..1fa2f90 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> @@ -80,6 +81,10 @@ struct netem_sched_data { u32 reorder; u32 corrupt; u32 rate; + s32 packet_overhead; + u32 cell_size; + u32 cell_size_reciprocal; + s32 cell_overhead; struct crndstate { u32 last; @@ -299,11 +304,23 @@ 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) +static psched_time_t packet_len_2_sched_time(unsigned int len, struct netem_sched_data *q) { - u64 ticks = (u64)len * NSEC_PER_SEC; + u64 ticks; - do_div(ticks, rate); + 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); } @@ -384,7 +401,7 @@ static int netem_enqueue(struct sk_buff *skb, struct Qdisc *sch) if (q->rate) { struct sk_buff_head *list = &q->qdisc->q; - delay += packet_len_2_sched_time(skb->len, q->rate); + delay += packet_len_2_sched_time(skb->len, q); if (!skb_queue_empty(list)) { /* @@ -568,6 +585,11 @@ static void get_rate(struct Qdisc *sch, const struct nlattr *attr) 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) @@ -909,6 +931,9 @@ static int netem_dump(struct Qdisc *sch, struct sk_buff *skb) 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) |