From e4ae004b84b315dd4b762e474f97403eac70f76a Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Mon, 30 Apr 2012 23:11:05 +0000 Subject: [PATCH] netem: add ECN capability Add ECN (Explicit Congestion Notification) marking capability to netem tc qdisc add dev eth0 root netem drop 0.5 ecn Instead of dropping packets, try to ECN mark them. Signed-off-by: Eric Dumazet Cc: Neal Cardwell Cc: Tom Herbert Cc: Hagen Paul Pfeifer Cc: Stephen Hemminger Acked-by: Hagen Paul Pfeifer Signed-off-by: David S. Miller --- include/linux/pkt_sched.h | 1 + net/sched/sch_netem.c | 18 +++++++++++++++--- 2 files changed, 16 insertions(+), 3 deletions(-) diff --git a/include/linux/pkt_sched.h b/include/linux/pkt_sched.h index 410b33d..ffe975c 100644 --- a/include/linux/pkt_sched.h +++ b/include/linux/pkt_sched.h @@ -509,6 +509,7 @@ enum { TCA_NETEM_CORRUPT, TCA_NETEM_LOSS, TCA_NETEM_RATE, + TCA_NETEM_ECN, __TCA_NETEM_MAX, }; diff --git a/net/sched/sch_netem.c b/net/sched/sch_netem.c index 1109731..231cd11 100644 --- a/net/sched/sch_netem.c +++ b/net/sched/sch_netem.c @@ -26,6 +26,7 @@ #include #include +#include #define VERSION "1.3" @@ -78,6 +79,7 @@ struct netem_sched_data { psched_tdiff_t jitter; u32 loss; + u32 ecn; u32 limit; u32 counter; u32 gap; @@ -374,9 +376,12 @@ static int netem_enqueue(struct sk_buff *skb, struct Qdisc *sch) ++count; /* Drop packet? */ - if (loss_event(q)) - --count; - + if (loss_event(q)) { + if (q->ecn && INET_ECN_set_ce(skb)) + sch->qstats.drops++; /* mark packet */ + else + --count; + } if (count == 0) { sch->qstats.drops++; kfree_skb(skb); @@ -706,6 +711,7 @@ static const struct nla_policy netem_policy[TCA_NETEM_MAX + 1] = { [TCA_NETEM_CORRUPT] = { .len = sizeof(struct tc_netem_corrupt) }, [TCA_NETEM_RATE] = { .len = sizeof(struct tc_netem_rate) }, [TCA_NETEM_LOSS] = { .type = NLA_NESTED }, + [TCA_NETEM_ECN] = { .type = NLA_U32 }, }; static int parse_attr(struct nlattr *tb[], int maxtype, struct nlattr *nla, @@ -776,6 +782,9 @@ static int netem_change(struct Qdisc *sch, struct nlattr *opt) if (tb[TCA_NETEM_RATE]) get_rate(sch, tb[TCA_NETEM_RATE]); + if (tb[TCA_NETEM_ECN]) + q->ecn = nla_get_u32(tb[TCA_NETEM_ECN]); + q->loss_model = CLG_RANDOM; if (tb[TCA_NETEM_LOSS]) ret = get_loss_clg(sch, tb[TCA_NETEM_LOSS]); @@ -902,6 +911,9 @@ static int netem_dump(struct Qdisc *sch, struct sk_buff *skb) if (nla_put(skb, TCA_NETEM_RATE, sizeof(rate), &rate)) goto nla_put_failure; + if (q->ecn && nla_put_u32(skb, TCA_NETEM_ECN, q->ecn)) + goto nla_put_failure; + if (dump_loss_model(q, skb) != 0) goto nla_put_failure; -- 2.7.4