From 48a8f519e0fe22a5c98523286b2a120841a11dd5 Mon Sep 17 00:00:00 2001 From: Patrick McHardy Date: Fri, 31 Oct 2008 00:44:18 -0700 Subject: pkt_sched: Add ->peek() methods for fifo, prio and SFQ qdiscs. From: Patrick McHardy Just as a demonstration how easy adding a peek operation to the work-conserving qdiscs actually is. It doesn't need to keep or change any internal state in many cases thanks to the guarantee that the packet will either be dequeued or, if another packet arrives, the upper qdisc will immediately ->peek again to reevaluate the state. (This is only slightly modified Patrick's patch.) Signed-off-by: Jarek Poplawski Signed-off-by: David S. Miller --- net/sched/sch_sfq.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) (limited to 'net/sched/sch_sfq.c') diff --git a/net/sched/sch_sfq.c b/net/sched/sch_sfq.c index fe1508ef0d3d..198b83d42ba8 100644 --- a/net/sched/sch_sfq.c +++ b/net/sched/sch_sfq.c @@ -391,8 +391,19 @@ sfq_requeue(struct sk_buff *skb, struct Qdisc *sch) return NET_XMIT_CN; } +static struct sk_buff * +sfq_peek(struct Qdisc *sch) +{ + struct sfq_sched_data *q = qdisc_priv(sch); + sfq_index a; + /* No active slots */ + if (q->tail == SFQ_DEPTH) + return NULL; + a = q->next[q->tail]; + return skb_peek(&q->qs[a]); +} static struct sk_buff * sfq_dequeue(struct Qdisc *sch) @@ -624,6 +635,7 @@ static struct Qdisc_ops sfq_qdisc_ops __read_mostly = { .priv_size = sizeof(struct sfq_sched_data), .enqueue = sfq_enqueue, .dequeue = sfq_dequeue, + .peek = sfq_peek, .requeue = sfq_requeue, .drop = sfq_drop, .init = sfq_init, -- cgit v1.2.1 From f30ab418a1d3c5a8b83493e7d70d6876a74aa0ce Mon Sep 17 00:00:00 2001 From: Jarek Poplawski Date: Thu, 13 Nov 2008 22:56:30 -0800 Subject: pkt_sched: Remove qdisc->ops->requeue() etc. After implementing qdisc->ops->peek() and changing sch_netem into classless qdisc there are no more qdisc->ops->requeue() users. This patch removes this method with its wrappers (qdisc_requeue()), and also unused qdisc->requeue structure. There are a few minor fixes of warnings (htb_enqueue()) and comments btw. The idea to kill ->requeue() and a similar patch were first developed by David S. Miller. Signed-off-by: Jarek Poplawski Signed-off-by: David S. Miller --- net/sched/sch_sfq.c | 63 ----------------------------------------------------- 1 file changed, 63 deletions(-) (limited to 'net/sched/sch_sfq.c') diff --git a/net/sched/sch_sfq.c b/net/sched/sch_sfq.c index 198b83d42ba8..ab8cfee3c9ce 100644 --- a/net/sched/sch_sfq.c +++ b/net/sched/sch_sfq.c @@ -329,68 +329,6 @@ sfq_enqueue(struct sk_buff *skb, struct Qdisc *sch) return NET_XMIT_CN; } -static int -sfq_requeue(struct sk_buff *skb, struct Qdisc *sch) -{ - struct sfq_sched_data *q = qdisc_priv(sch); - unsigned int hash; - sfq_index x; - int ret; - - hash = sfq_classify(skb, sch, &ret); - if (hash == 0) { - if (ret & __NET_XMIT_BYPASS) - sch->qstats.drops++; - kfree_skb(skb); - return ret; - } - hash--; - - x = q->ht[hash]; - if (x == SFQ_DEPTH) { - q->ht[hash] = x = q->dep[SFQ_DEPTH].next; - q->hash[x] = hash; - } - - sch->qstats.backlog += qdisc_pkt_len(skb); - __skb_queue_head(&q->qs[x], skb); - /* If selected queue has length q->limit+1, this means that - * all another queues are empty and we do simple tail drop. - * This packet is still requeued at head of queue, tail packet - * is dropped. - */ - if (q->qs[x].qlen > q->limit) { - skb = q->qs[x].prev; - __skb_unlink(skb, &q->qs[x]); - sch->qstats.drops++; - sch->qstats.backlog -= qdisc_pkt_len(skb); - kfree_skb(skb); - return NET_XMIT_CN; - } - - sfq_inc(q, x); - if (q->qs[x].qlen == 1) { /* The flow is new */ - if (q->tail == SFQ_DEPTH) { /* It is the first flow */ - q->tail = x; - q->next[x] = x; - q->allot[x] = q->quantum; - } else { - q->next[x] = q->next[q->tail]; - q->next[q->tail] = x; - q->tail = x; - } - } - - if (++sch->q.qlen <= q->limit) { - sch->qstats.requeues++; - return 0; - } - - sch->qstats.drops++; - sfq_drop(sch); - return NET_XMIT_CN; -} - static struct sk_buff * sfq_peek(struct Qdisc *sch) { @@ -636,7 +574,6 @@ static struct Qdisc_ops sfq_qdisc_ops __read_mostly = { .enqueue = sfq_enqueue, .dequeue = sfq_dequeue, .peek = sfq_peek, - .requeue = sfq_requeue, .drop = sfq_drop, .init = sfq_init, .reset = sfq_reset, -- cgit v1.2.1 From 7f3ff4f63f76c2702da6041d2da5eb30fac407f6 Mon Sep 17 00:00:00 2001 From: Jarek Poplawski Date: Sun, 21 Dec 2008 20:14:48 -0800 Subject: pkt_sched: Annotate uninitialized var in sfq_enqueue() Some gcc versions warn that ret may be used uninitialized in sfq_enqueue(). It's a false positive, so let's annotate this. Signed-off-by: Jarek Poplawski Signed-off-by: David S. Miller --- net/sched/sch_sfq.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'net/sched/sch_sfq.c') diff --git a/net/sched/sch_sfq.c b/net/sched/sch_sfq.c index ab8cfee3c9ce..f3965df00559 100644 --- a/net/sched/sch_sfq.c +++ b/net/sched/sch_sfq.c @@ -281,7 +281,7 @@ sfq_enqueue(struct sk_buff *skb, struct Qdisc *sch) struct sfq_sched_data *q = qdisc_priv(sch); unsigned int hash; sfq_index x; - int ret; + int uninitialized_var(ret); hash = sfq_classify(skb, sch, &ret); if (hash == 0) { -- cgit v1.2.1