net_sched: add the ability to defer skb freeing

[cascardo/linux.git] / net / sched / sch_generic.c

diff --git a/net/sched/sch_generic.c b/net/sched/sch_generic.c
index 269dd71..773b632 100644 (file)
--- a/net/sched/sch_generic.c
+++ b/net/sched/sch_generic.c
@@ -49,6 +49,7 @@ static inline int dev_requeue_skb(struct sk_buff *skb, struct Qdisc *q)
 {
        q->gso_skb = skb;
        q->qstats.requeues++;
+       qdisc_qstats_backlog_inc(q, skb);
        q->q.qlen++;    /* it's still part of the queue */
        __netif_schedule(q);
 
@@ -92,6 +93,7 @@ static struct sk_buff *dequeue_skb(struct Qdisc *q, bool *validate,
                txq = skb_get_tx_queue(txq->dev, skb);
                if (!netif_xmit_frozen_or_stopped(txq)) {
                        q->gso_skb = NULL;
+                       qdisc_qstats_backlog_dec(q, skb);
                        q->q.qlen--;
                } else
                        skb = NULL;
@@ -110,7 +112,7 @@ static struct sk_buff *dequeue_skb(struct Qdisc *q, bool *validate,
 
 /*
  * Transmit possibly several skbs, and handle the return status as
- * required. Holding the __QDISC___STATE_RUNNING bit guarantees that
+ * required. Owning running seqcount bit guarantees that
  * only one CPU can execute this function.
  *
  * Returns to the caller:
@@ -163,7 +165,7 @@ int sch_direct_xmit(struct sk_buff *skb, struct Qdisc *q,
 /*
  * NOTE: Called under qdisc_lock(q) with locally disabled BH.
  *
- * __QDISC___STATE_RUNNING guarantees only one CPU can process
+ * running seqcount guarantees only one CPU can process
  * this qdisc at a time. qdisc_lock(q) serializes queue accesses for
  * this queue.
  *
@@ -379,6 +381,7 @@ struct Qdisc noop_qdisc = {
        .list           =       LIST_HEAD_INIT(noop_qdisc.list),
        .q.lock         =       __SPIN_LOCK_UNLOCKED(noop_qdisc.q.lock),
        .dev_queue      =       &noop_netdev_queue,
+       .running        =       SEQCNT_ZERO(noop_qdisc.running),
        .busylock       =       __SPIN_LOCK_UNLOCKED(noop_qdisc.busylock),
 };
 EXPORT_SYMBOL(noop_qdisc);
@@ -490,7 +493,7 @@ static void pfifo_fast_reset(struct Qdisc *qdisc)
        struct pfifo_fast_priv *priv = qdisc_priv(qdisc);
 
        for (prio = 0; prio < PFIFO_FAST_BANDS; prio++)
-               __qdisc_reset_queue(qdisc, band2list(priv, prio));
+               __qdisc_reset_queue(band2list(priv, prio));
 
        priv->bitmap = 0;
        qdisc->qstats.backlog = 0;
@@ -537,6 +540,7 @@ struct Qdisc_ops pfifo_fast_ops __read_mostly = {
 EXPORT_SYMBOL(pfifo_fast_ops);
 
 static struct lock_class_key qdisc_tx_busylock;
+static struct lock_class_key qdisc_running_key;
 
 struct Qdisc *qdisc_alloc(struct netdev_queue *dev_queue,
                          const struct Qdisc_ops *ops)
@@ -570,6 +574,10 @@ struct Qdisc *qdisc_alloc(struct netdev_queue *dev_queue,
        lockdep_set_class(&sch->busylock,
                          dev->qdisc_tx_busylock ?: &qdisc_tx_busylock);
 
+       seqcount_init(&sch->running);
+       lockdep_set_class(&sch->running,
+                         dev->qdisc_running_key ?: &qdisc_running_key);
+
        sch->ops = ops;
        sch->enqueue = ops->enqueue;
        sch->dequeue = ops->dequeue;