From 07aaa11540828f4482c09e1a936a1f63cdb9fc9d Mon Sep 17 00:00:00 2001 From: Stephen Hemminger Date: Thu, 3 Nov 2005 13:43:07 -0800 Subject: [NETEM]: use PSCHED_LESS Convert netem to use PSCHED_LESS and warn if requeue fails. With some of the psched clock sources, the subtraction doesn't work always work right without wrapping. Signed-off-by: Stephen Hemminger Signed-off-by: Arnaldo Carvalho de Melo --- net/sched/sch_netem.c | 34 ++++++++++++++++++++++------------ 1 file changed, 22 insertions(+), 12 deletions(-) (limited to 'net') diff --git a/net/sched/sch_netem.c b/net/sched/sch_netem.c index bb9bf8d5003c..d871fe7f81a9 100644 --- a/net/sched/sch_netem.c +++ b/net/sched/sch_netem.c @@ -185,10 +185,13 @@ static int netem_enqueue(struct sk_buff *skb, struct Qdisc *sch) || q->counter < q->gap /* inside last reordering gap */ || q->reorder < get_crandom(&q->reorder_cor)) { psched_time_t now; + psched_tdiff_t delay; + + delay = tabledist(q->latency, q->jitter, + &q->delay_cor, q->delay_dist); + PSCHED_GET_TIME(now); - PSCHED_TADD2(now, tabledist(q->latency, q->jitter, - &q->delay_cor, q->delay_dist), - cb->time_to_send); + PSCHED_TADD2(now, delay, cb->time_to_send); ++q->counter; ret = q->qdisc->enqueue(skb, q->qdisc); } else { @@ -248,24 +251,31 @@ static struct sk_buff *netem_dequeue(struct Qdisc *sch) const struct netem_skb_cb *cb = (const struct netem_skb_cb *)skb->cb; psched_time_t now; - long delay; /* if more time remaining? */ PSCHED_GET_TIME(now); - delay = PSCHED_US2JIFFIE(PSCHED_TDIFF(cb->time_to_send, now)); - pr_debug("netem_run: skb=%p delay=%ld\n", skb, delay); - if (delay <= 0) { + + if (PSCHED_TLESS(cb->time_to_send, now)) { pr_debug("netem_dequeue: return skb=%p\n", skb); sch->q.qlen--; sch->flags &= ~TCQ_F_THROTTLED; return skb; - } + } else { + psched_tdiff_t delay = PSCHED_TDIFF(cb->time_to_send, now); - mod_timer(&q->timer, jiffies + delay); - sch->flags |= TCQ_F_THROTTLED; + if (q->qdisc->ops->requeue(skb, q->qdisc) != NET_XMIT_SUCCESS) { + sch->qstats.drops++; - if (q->qdisc->ops->requeue(skb, q->qdisc) != 0) - sch->qstats.drops++; + /* After this qlen is confused */ + printk(KERN_ERR "netem: queue discpline %s could not requeue\n", + q->qdisc->ops->id); + + sch->q.qlen--; + } + + mod_timer(&q->timer, jiffies + PSCHED_US2JIFFIE(delay)); + sch->flags |= TCQ_F_THROTTLED; + } } return NULL; -- cgit v1.2.3