From 8e3af97899db433111287e07d5105189f56fe191 Mon Sep 17 00:00:00 2001 From: Jarek Poplawski Date: Fri, 31 Oct 2008 00:45:55 -0700 Subject: [PATCH] pkt_sched: Add qdisc->ops->peek() implementation. Add qdisc->ops->peek() implementation for work-conserving qdiscs. With feedback from Patrick McHardy. Signed-off-by: Jarek Poplawski Signed-off-by: David S. Miller --- net/sched/sch_atm.c | 10 ++++++++++ net/sched/sch_blackhole.c | 1 + net/sched/sch_dsmark.c | 10 ++++++++++ net/sched/sch_gred.c | 1 + net/sched/sch_multiq.c | 29 +++++++++++++++++++++++++++++ net/sched/sch_netem.c | 1 + net/sched/sch_red.c | 9 +++++++++ net/sched/sch_teql.c | 8 ++++++++ 8 files changed, 69 insertions(+) diff --git a/net/sched/sch_atm.c b/net/sched/sch_atm.c index 43d37256c15e..f9eac0818d18 100644 --- a/net/sched/sch_atm.c +++ b/net/sched/sch_atm.c @@ -522,6 +522,15 @@ static struct sk_buff *atm_tc_dequeue(struct Qdisc *sch) return skb; } +static struct sk_buff *atm_tc_peek(struct Qdisc *sch) +{ + struct atm_qdisc_data *p = qdisc_priv(sch); + + pr_debug("atm_tc_peek(sch %p,[qdisc %p])\n", sch, p); + + return p->link.q->ops->peek(p->link.q); +} + static int atm_tc_requeue(struct sk_buff *skb, struct Qdisc *sch) { struct atm_qdisc_data *p = qdisc_priv(sch); @@ -694,6 +703,7 @@ static struct Qdisc_ops atm_qdisc_ops __read_mostly = { .priv_size = sizeof(struct atm_qdisc_data), .enqueue = atm_tc_enqueue, .dequeue = atm_tc_dequeue, + .peek = atm_tc_peek, .requeue = atm_tc_requeue, .drop = atm_tc_drop, .init = atm_tc_init, diff --git a/net/sched/sch_blackhole.c b/net/sched/sch_blackhole.c index 507fb488bc98..094a874b48bc 100644 --- a/net/sched/sch_blackhole.c +++ b/net/sched/sch_blackhole.c @@ -33,6 +33,7 @@ static struct Qdisc_ops blackhole_qdisc_ops __read_mostly = { .priv_size = 0, .enqueue = blackhole_enqueue, .dequeue = blackhole_dequeue, + .peek = blackhole_dequeue, .owner = THIS_MODULE, }; diff --git a/net/sched/sch_dsmark.c b/net/sched/sch_dsmark.c index ba43aab3a851..3e491479ea86 100644 --- a/net/sched/sch_dsmark.c +++ b/net/sched/sch_dsmark.c @@ -313,6 +313,15 @@ static struct sk_buff *dsmark_dequeue(struct Qdisc *sch) return skb; } +static struct sk_buff *dsmark_peek(struct Qdisc *sch) +{ + struct dsmark_qdisc_data *p = qdisc_priv(sch); + + pr_debug("dsmark_peek(sch %p,[qdisc %p])\n", sch, p); + + return p->q->ops->peek(p->q); +} + static int dsmark_requeue(struct sk_buff *skb, struct Qdisc *sch) { struct dsmark_qdisc_data *p = qdisc_priv(sch); @@ -496,6 +505,7 @@ static struct Qdisc_ops dsmark_qdisc_ops __read_mostly = { .priv_size = sizeof(struct dsmark_qdisc_data), .enqueue = dsmark_enqueue, .dequeue = dsmark_dequeue, + .peek = dsmark_peek, .requeue = dsmark_requeue, .drop = dsmark_drop, .init = dsmark_init, diff --git a/net/sched/sch_gred.c b/net/sched/sch_gred.c index c1ad6b8de105..cb20ee3b9fc2 100644 --- a/net/sched/sch_gred.c +++ b/net/sched/sch_gred.c @@ -602,6 +602,7 @@ static struct Qdisc_ops gred_qdisc_ops __read_mostly = { .priv_size = sizeof(struct gred_sched), .enqueue = gred_enqueue, .dequeue = gred_dequeue, + .peek = qdisc_peek_head, .requeue = gred_requeue, .drop = gred_drop, .init = gred_init, diff --git a/net/sched/sch_multiq.c b/net/sched/sch_multiq.c index 915f3149dde2..155648d23b7c 100644 --- a/net/sched/sch_multiq.c +++ b/net/sched/sch_multiq.c @@ -155,6 +155,34 @@ static struct sk_buff *multiq_dequeue(struct Qdisc *sch) } +static struct sk_buff *multiq_peek(struct Qdisc *sch) +{ + struct multiq_sched_data *q = qdisc_priv(sch); + unsigned int curband = q->curband; + struct Qdisc *qdisc; + struct sk_buff *skb; + int band; + + for (band = 0; band < q->bands; band++) { + /* cycle through bands to ensure fairness */ + curband++; + if (curband >= q->bands) + curband = 0; + + /* Check that target subqueue is available before + * pulling an skb to avoid excessive requeues + */ + if (!__netif_subqueue_stopped(qdisc_dev(sch), curband)) { + qdisc = q->queues[curband]; + skb = qdisc->ops->peek(qdisc); + if (skb) + return skb; + } + } + return NULL; + +} + static unsigned int multiq_drop(struct Qdisc *sch) { struct multiq_sched_data *q = qdisc_priv(sch); @@ -451,6 +479,7 @@ static struct Qdisc_ops multiq_qdisc_ops __read_mostly = { .priv_size = sizeof(struct multiq_sched_data), .enqueue = multiq_enqueue, .dequeue = multiq_dequeue, + .peek = multiq_peek, .requeue = multiq_requeue, .drop = multiq_drop, .init = multiq_init, diff --git a/net/sched/sch_netem.c b/net/sched/sch_netem.c index a11959908d9a..2898d9dc31eb 100644 --- a/net/sched/sch_netem.c +++ b/net/sched/sch_netem.c @@ -541,6 +541,7 @@ static struct Qdisc_ops tfifo_qdisc_ops __read_mostly = { .priv_size = sizeof(struct fifo_sched_data), .enqueue = tfifo_enqueue, .dequeue = qdisc_dequeue_head, + .peek = qdisc_peek_head, .requeue = qdisc_requeue, .drop = qdisc_queue_drop, .init = tfifo_init, diff --git a/net/sched/sch_red.c b/net/sched/sch_red.c index 5da05839e225..7abc51454c2d 100644 --- a/net/sched/sch_red.c +++ b/net/sched/sch_red.c @@ -140,6 +140,14 @@ static struct sk_buff * red_dequeue(struct Qdisc* sch) return skb; } +static struct sk_buff * red_peek(struct Qdisc* sch) +{ + struct red_sched_data *q = qdisc_priv(sch); + struct Qdisc *child = q->qdisc; + + return child->ops->peek(child); +} + static unsigned int red_drop(struct Qdisc* sch) { struct red_sched_data *q = qdisc_priv(sch); @@ -361,6 +369,7 @@ static struct Qdisc_ops red_qdisc_ops __read_mostly = { .cl_ops = &red_class_ops, .enqueue = red_enqueue, .dequeue = red_dequeue, + .peek = red_peek, .requeue = red_requeue, .drop = red_drop, .init = red_init, diff --git a/net/sched/sch_teql.c b/net/sched/sch_teql.c index d35ef059abb1..bf03e7fa1849 100644 --- a/net/sched/sch_teql.c +++ b/net/sched/sch_teql.c @@ -123,6 +123,13 @@ teql_dequeue(struct Qdisc* sch) return skb; } +static struct sk_buff * +teql_peek(struct Qdisc* sch) +{ + /* teql is meant to be used as root qdisc */ + return NULL; +} + static __inline__ void teql_neigh_release(struct neighbour *n) { @@ -433,6 +440,7 @@ static __init void teql_master_setup(struct net_device *dev) ops->enqueue = teql_enqueue; ops->dequeue = teql_dequeue; + ops->peek = teql_peek; ops->requeue = teql_requeue; ops->init = teql_qdisc_init; ops->reset = teql_reset; -- GitLab