X-Git-Url: http://ftp.safe.ca/?a=blobdiff_plain;f=net%2Fsched%2Fsch_generic.c;h=a63029ef3eddc9e1bc19cbc552f327e6fdafa8aa;hb=7fee226a;hp=9c9cd4d94890d1b1c5fb7d582af730f37248cfc0;hpb=c3f26a269c2421f97f10cf8ed05d5099b573af4d;p=safe%2Fjmp%2Flinux-2.6

diff --git a/net/sched/sch_generic.c b/net/sched/sch_generic.c
index 9c9cd4d..a63029e 100644
--- a/net/sched/sch_generic.c
+++ b/net/sched/sch_generic.c
@@ -24,12 +24,14 @@
 #include <linux/init.h>
 #include <linux/rcupdate.h>
 #include <linux/list.h>
+#include <linux/slab.h>
 #include <net/pkt_sched.h>
+#include <net/dst.h>
 
 /* Main transmission queue. */
 
 /* Modifications to data participating in scheduling must be protected with
- * qdisc_root_lock(qdisc) spinlock.
+ * qdisc_lock(qdisc) spinlock.
  *
  * The idea is the following:
  * - enqueue, dequeue are serialized via qdisc root lock
@@ -37,30 +39,36 @@
  * - updates to tree and tree walking are only done under the rtnl mutex.
  */
 
-static inline int qdisc_qlen(struct Qdisc *q)
-{
-	return q->q.qlen;
-}
-
 static inline int dev_requeue_skb(struct sk_buff *skb, struct Qdisc *q)
 {
-	if (unlikely(skb->next))
-		q->gso_skb = skb;
-	else
-		q->ops->requeue(skb, q);
-
+	skb_dst_force(skb);
+	q->gso_skb = skb;
+	q->qstats.requeues++;
+	q->q.qlen++;	/* it's still part of the queue */
 	__netif_schedule(q);
+
 	return 0;
 }
 
 static inline struct sk_buff *dequeue_skb(struct Qdisc *q)
 {
-	struct sk_buff *skb;
+	struct sk_buff *skb = q->gso_skb;
+
+	if (unlikely(skb)) {
+		struct net_device *dev = qdisc_dev(q);
+		struct netdev_queue *txq;
 
-	if ((skb = q->gso_skb))
-		q->gso_skb = NULL;
-	else
+		/* check the reason of requeuing without tx lock first */
+		txq = netdev_get_tx_queue(dev, skb_get_queue_mapping(skb));
+		if (!netif_tx_queue_stopped(txq) &&
+		    !netif_tx_queue_frozen(txq)) {
+			q->gso_skb = NULL;
+			q->q.qlen--;
+		} else
+			skb = NULL;
+	} else {
 		skb = q->dequeue(q);
+	}
 
 	return skb;
 }
@@ -88,7 +96,7 @@ static inline int handle_dev_cpu_collision(struct sk_buff *skb,
 		 * Another cpu is holding lock, requeue & delay xmits for
 		 * some time.
 		 */
-		__get_cpu_var(netdev_rx_stat).cpu_collision++;
+		__get_cpu_var(softnet_data).cpu_collision++;
 		ret = dev_requeue_skb(skb, q);
 	}
 
@@ -96,71 +104,44 @@ static inline int handle_dev_cpu_collision(struct sk_buff *skb,
 }
 
 /*
- * NOTE: Called under qdisc_lock(q) with locally disabled BH.
- *
- * __QDISC_STATE_RUNNING guarantees only one CPU can process
- * this qdisc at a time. qdisc_lock(q) serializes queue accesses for
- * this queue.
- *
- *  netif_tx_lock serializes accesses to device driver.
- *
- *  qdisc_lock(q) and netif_tx_lock are mutually exclusive,
- *  if one is grabbed, another must be free.
- *
- * Note, that this procedure can be called by a watchdog timer
+ * Transmit one skb, and handle the return status as required. Holding the
+ * __QDISC_STATE_RUNNING bit guarantees that only one CPU can execute this
+ * function.
  *
  * Returns to the caller:
  *				0  - queue is empty or throttled.
  *				>0 - queue is not empty.
- *
  */
-static inline int qdisc_restart(struct Qdisc *q)
+int sch_direct_xmit(struct sk_buff *skb, struct Qdisc *q,
+		    struct net_device *dev, struct netdev_queue *txq,
+		    spinlock_t *root_lock)
 {
-	struct netdev_queue *txq;
 	int ret = NETDEV_TX_BUSY;
-	struct net_device *dev;
-	spinlock_t *root_lock;
-	struct sk_buff *skb;
-
-	/* Dequeue packet */
-	if (unlikely((skb = dequeue_skb(q)) == NULL))
-		return 0;
-
-	root_lock = qdisc_root_lock(q);
 
 	/* And release qdisc */
 	spin_unlock(root_lock);
 
-	dev = qdisc_dev(q);
-	txq = netdev_get_tx_queue(dev, skb_get_queue_mapping(skb));
-
 	HARD_TX_LOCK(dev, txq, smp_processor_id());
-	if (!netif_tx_queue_stopped(txq) &&
-	    !netif_tx_queue_frozen(txq))
+	if (!netif_tx_queue_stopped(txq) && !netif_tx_queue_frozen(txq))
 		ret = dev_hard_start_xmit(skb, dev, txq);
+
 	HARD_TX_UNLOCK(dev, txq);
 
 	spin_lock(root_lock);
 
-	switch (ret) {
-	case NETDEV_TX_OK:
-		/* Driver sent out skb successfully */
+	if (dev_xmit_complete(ret)) {
+		/* Driver sent out skb successfully or skb was consumed */
 		ret = qdisc_qlen(q);
-		break;
-
-	case NETDEV_TX_LOCKED:
+	} else if (ret == NETDEV_TX_LOCKED) {
 		/* Driver try lock failed */
 		ret = handle_dev_cpu_collision(skb, txq, q);
-		break;
-
-	default:
+	} else {
 		/* Driver returned NETDEV_TX_BUSY - requeue skb */
 		if (unlikely (ret != NETDEV_TX_BUSY && net_ratelimit()))
 			printk(KERN_WARNING "BUG %s code %d qlen %d\n",
 			       dev->name, ret, q->q.qlen);
 
 		ret = dev_requeue_skb(skb, q);
-		break;
 	}
 
 	if (ret && (netif_tx_queue_stopped(txq) ||
@@ -170,6 +151,44 @@ static inline int qdisc_restart(struct Qdisc *q)
 	return ret;
 }
 
+/*
+ * NOTE: Called under qdisc_lock(q) with locally disabled BH.
+ *
+ * __QDISC_STATE_RUNNING guarantees only one CPU can process
+ * this qdisc at a time. qdisc_lock(q) serializes queue accesses for
+ * this queue.
+ *
+ *  netif_tx_lock serializes accesses to device driver.
+ *
+ *  qdisc_lock(q) and netif_tx_lock are mutually exclusive,
+ *  if one is grabbed, another must be free.
+ *
+ * Note, that this procedure can be called by a watchdog timer
+ *
+ * Returns to the caller:
+ *				0  - queue is empty or throttled.
+ *				>0 - queue is not empty.
+ *
+ */
+static inline int qdisc_restart(struct Qdisc *q)
+{
+	struct netdev_queue *txq;
+	struct net_device *dev;
+	spinlock_t *root_lock;
+	struct sk_buff *skb;
+
+	/* Dequeue packet */
+	skb = dequeue_skb(q);
+	if (unlikely(!skb))
+		return 0;
+	WARN_ON_ONCE(skb_dst_is_noref(skb));
+	root_lock = qdisc_lock(q);
+	dev = qdisc_dev(q);
+	txq = netdev_get_tx_queue(dev, skb_get_queue_mapping(skb));
+
+	return sch_direct_xmit(skb, q, dev, txq, root_lock);
+}
+
 void __qdisc_run(struct Qdisc *q)
 {
 	unsigned long start_time = jiffies;
@@ -189,6 +208,21 @@ void __qdisc_run(struct Qdisc *q)
 	clear_bit(__QDISC_STATE_RUNNING, &q->state);
 }
 
+unsigned long dev_trans_start(struct net_device *dev)
+{
+	unsigned long val, res = dev->trans_start;
+	unsigned int i;
+
+	for (i = 0; i < dev->num_tx_queues; i++) {
+		val = netdev_get_tx_queue(dev, i)->trans_start;
+		if (val && time_after(val, res))
+			res = val;
+	}
+	dev->trans_start = res;
+	return res;
+}
+EXPORT_SYMBOL(dev_trans_start);
+
 static void dev_watchdog(unsigned long arg)
 {
 	struct net_device *dev = (struct net_device *)arg;
@@ -198,27 +232,31 @@ static void dev_watchdog(unsigned long arg)
 		if (netif_device_present(dev) &&
 		    netif_running(dev) &&
 		    netif_carrier_ok(dev)) {
-			int some_queue_stopped = 0;
+			int some_queue_timedout = 0;
 			unsigned int i;
+			unsigned long trans_start;
 
 			for (i = 0; i < dev->num_tx_queues; i++) {
 				struct netdev_queue *txq;
 
 				txq = netdev_get_tx_queue(dev, i);
-				if (netif_tx_queue_stopped(txq)) {
-					some_queue_stopped = 1;
+				/*
+				 * old device drivers set dev->trans_start
+				 */
+				trans_start = txq->trans_start ? : dev->trans_start;
+				if (netif_tx_queue_stopped(txq) &&
+				    time_after(jiffies, (trans_start +
+							 dev->watchdog_timeo))) {
+					some_queue_timedout = 1;
 					break;
 				}
 			}
 
-			if (some_queue_stopped &&
-			    time_after(jiffies, (dev->trans_start +
-						 dev->watchdog_timeo))) {
+			if (some_queue_timedout) {
 				char drivername[64];
-				printk(KERN_INFO "NETDEV WATCHDOG: %s (%s): transmit timed out\n",
-				       dev->name, netdev_drivername(dev, drivername, 64));
-				dev->tx_timeout(dev);
-				WARN_ON_ONCE(1);
+				WARN_ONCE(1, KERN_INFO "NETDEV WATCHDOG: %s (%s): transmit queue %u timed out\n",
+				       dev->name, netdev_drivername(dev, drivername, 64), i);
+				dev->netdev_ops->ndo_tx_timeout(dev);
 			}
 			if (!mod_timer(&dev->watchdog_timer,
 				       round_jiffies(jiffies +
@@ -233,7 +271,7 @@ static void dev_watchdog(unsigned long arg)
 
 void __netdev_watchdog_up(struct net_device *dev)
 {
-	if (dev->tx_timeout) {
+	if (dev->netdev_ops->ndo_tx_timeout) {
 		if (dev->watchdog_timeo <= 0)
 			dev->watchdog_timeo = 5*HZ;
 		if (!mod_timer(&dev->watchdog_timer,
@@ -264,6 +302,8 @@ static void dev_watchdog_down(struct net_device *dev)
 void netif_carrier_on(struct net_device *dev)
 {
 	if (test_and_clear_bit(__LINK_STATE_NOCARRIER, &dev->state)) {
+		if (dev->reg_state == NETREG_UNINITIALIZED)
+			return;
 		linkwatch_fire_event(dev);
 		if (netif_running(dev))
 			__netdev_watchdog_up(dev);
@@ -279,8 +319,11 @@ EXPORT_SYMBOL(netif_carrier_on);
  */
 void netif_carrier_off(struct net_device *dev)
 {
-	if (!test_and_set_bit(__LINK_STATE_NOCARRIER, &dev->state))
+	if (!test_and_set_bit(__LINK_STATE_NOCARRIER, &dev->state)) {
+		if (dev->reg_state == NETREG_UNINITIALIZED)
+			return;
 		linkwatch_fire_event(dev);
+	}
 }
 EXPORT_SYMBOL(netif_carrier_off);
 
@@ -300,26 +343,18 @@ static struct sk_buff *noop_dequeue(struct Qdisc * qdisc)
 	return NULL;
 }
 
-static int noop_requeue(struct sk_buff *skb, struct Qdisc* qdisc)
-{
-	if (net_ratelimit())
-		printk(KERN_DEBUG "%s deferred output. It is buggy.\n",
-		       skb->dev->name);
-	kfree_skb(skb);
-	return NET_XMIT_CN;
-}
-
 struct Qdisc_ops noop_qdisc_ops __read_mostly = {
 	.id		=	"noop",
 	.priv_size	=	0,
 	.enqueue	=	noop_enqueue,
 	.dequeue	=	noop_dequeue,
-	.requeue	=	noop_requeue,
+	.peek		=	noop_dequeue,
 	.owner		=	THIS_MODULE,
 };
 
 static struct netdev_queue noop_netdev_queue = {
 	.qdisc		=	&noop_qdisc,
+	.qdisc_sleeping	=	&noop_qdisc,
 };
 
 struct Qdisc noop_qdisc = {
@@ -338,13 +373,14 @@ static struct Qdisc_ops noqueue_qdisc_ops __read_mostly = {
 	.priv_size	=	0,
 	.enqueue	=	noop_enqueue,
 	.dequeue	=	noop_dequeue,
-	.requeue	=	noop_requeue,
+	.peek		=	noop_dequeue,
 	.owner		=	THIS_MODULE,
 };
 
 static struct Qdisc noqueue_qdisc;
 static struct netdev_queue noqueue_netdev_queue = {
 	.qdisc		=	&noqueue_qdisc,
+	.qdisc_sleeping	=	&noqueue_qdisc,
 };
 
 static struct Qdisc noqueue_qdisc = {
@@ -367,18 +403,38 @@ static const u8 prio2band[TC_PRIO_MAX+1] =
 
 #define PFIFO_FAST_BANDS 3
 
-static inline struct sk_buff_head *prio2list(struct sk_buff *skb,
-					     struct Qdisc *qdisc)
+/*
+ * Private data for a pfifo_fast scheduler containing:
+ * 	- queues for the three band
+ * 	- bitmap indicating which of the bands contain skbs
+ */
+struct pfifo_fast_priv {
+	u32 bitmap;
+	struct sk_buff_head q[PFIFO_FAST_BANDS];
+};
+
+/*
+ * Convert a bitmap to the first band number where an skb is queued, where:
+ * 	bitmap=0 means there are no skbs on any band.
+ * 	bitmap=1 means there is an skb on band 0.
+ *	bitmap=7 means there are skbs on all 3 bands, etc.
+ */
+static const int bitmap2band[] = {-1, 0, 1, 0, 2, 0, 1, 0};
+
+static inline struct sk_buff_head *band2list(struct pfifo_fast_priv *priv,
+					     int band)
 {
-	struct sk_buff_head *list = qdisc_priv(qdisc);
-	return list + prio2band[skb->priority & TC_PRIO_MAX];
+	return priv->q + band;
 }
 
 static int pfifo_fast_enqueue(struct sk_buff *skb, struct Qdisc* qdisc)
 {
-	struct sk_buff_head *list = prio2list(skb, qdisc);
+	if (skb_queue_len(&qdisc->q) < qdisc_dev(qdisc)->tx_queue_len) {
+		int band = prio2band[skb->priority & TC_PRIO_MAX];
+		struct pfifo_fast_priv *priv = qdisc_priv(qdisc);
+		struct sk_buff_head *list = band2list(priv, band);
 
-	if (skb_queue_len(list) < qdisc_dev(qdisc)->tx_queue_len) {
+		priv->bitmap |= (1 << band);
 		qdisc->q.qlen++;
 		return __qdisc_enqueue_tail(skb, qdisc, list);
 	}
@@ -388,33 +444,46 @@ static int pfifo_fast_enqueue(struct sk_buff *skb, struct Qdisc* qdisc)
 
 static struct sk_buff *pfifo_fast_dequeue(struct Qdisc* qdisc)
 {
-	int prio;
-	struct sk_buff_head *list = qdisc_priv(qdisc);
+	struct pfifo_fast_priv *priv = qdisc_priv(qdisc);
+	int band = bitmap2band[priv->bitmap];
 
-	for (prio = 0; prio < PFIFO_FAST_BANDS; prio++) {
-		if (!skb_queue_empty(list + prio)) {
-			qdisc->q.qlen--;
-			return __qdisc_dequeue_head(qdisc, list + prio);
-		}
+	if (likely(band >= 0)) {
+		struct sk_buff_head *list = band2list(priv, band);
+		struct sk_buff *skb = __qdisc_dequeue_head(qdisc, list);
+
+		qdisc->q.qlen--;
+		if (skb_queue_empty(list))
+			priv->bitmap &= ~(1 << band);
+
+		return skb;
 	}
 
 	return NULL;
 }
 
-static int pfifo_fast_requeue(struct sk_buff *skb, struct Qdisc* qdisc)
+static struct sk_buff *pfifo_fast_peek(struct Qdisc* qdisc)
 {
-	qdisc->q.qlen++;
-	return __qdisc_requeue(skb, qdisc, prio2list(skb, qdisc));
+	struct pfifo_fast_priv *priv = qdisc_priv(qdisc);
+	int band = bitmap2band[priv->bitmap];
+
+	if (band >= 0) {
+		struct sk_buff_head *list = band2list(priv, band);
+
+		return skb_peek(list);
+	}
+
+	return NULL;
 }
 
 static void pfifo_fast_reset(struct Qdisc* qdisc)
 {
 	int prio;
-	struct sk_buff_head *list = qdisc_priv(qdisc);
+	struct pfifo_fast_priv *priv = qdisc_priv(qdisc);
 
 	for (prio = 0; prio < PFIFO_FAST_BANDS; prio++)
-		__qdisc_reset_queue(qdisc, list + prio);
+		__qdisc_reset_queue(qdisc, band2list(priv, prio));
 
+	priv->bitmap = 0;
 	qdisc->qstats.backlog = 0;
 	qdisc->q.qlen = 0;
 }
@@ -434,20 +503,20 @@ nla_put_failure:
 static int pfifo_fast_init(struct Qdisc *qdisc, struct nlattr *opt)
 {
 	int prio;
-	struct sk_buff_head *list = qdisc_priv(qdisc);
+	struct pfifo_fast_priv *priv = qdisc_priv(qdisc);
 
 	for (prio = 0; prio < PFIFO_FAST_BANDS; prio++)
-		skb_queue_head_init(list + prio);
+		skb_queue_head_init(band2list(priv, prio));
 
 	return 0;
 }
 
-static struct Qdisc_ops pfifo_fast_ops __read_mostly = {
+struct Qdisc_ops pfifo_fast_ops __read_mostly = {
 	.id		=	"pfifo_fast",
-	.priv_size	=	PFIFO_FAST_BANDS * sizeof(struct sk_buff_head),
+	.priv_size	=	sizeof(struct pfifo_fast_priv),
 	.enqueue	=	pfifo_fast_enqueue,
 	.dequeue	=	pfifo_fast_dequeue,
-	.requeue	=	pfifo_fast_requeue,
+	.peek		=	pfifo_fast_peek,
 	.init		=	pfifo_fast_init,
 	.reset		=	pfifo_fast_reset,
 	.dump		=	pfifo_fast_dump,
@@ -462,7 +531,7 @@ struct Qdisc *qdisc_alloc(struct netdev_queue *dev_queue,
 	unsigned int size;
 	int err = -ENOBUFS;
 
-	/* ensure that the Qdisc and the private data are 32-byte aligned */
+	/* ensure that the Qdisc and the private data are 64-byte aligned */
 	size = QDISC_ALIGN(sizeof(*sch));
 	size += ops->priv_size + (QDISC_ALIGNTO - 1);
 
@@ -507,7 +576,7 @@ errout:
 }
 EXPORT_SYMBOL(qdisc_create_dflt);
 
-/* Under qdisc_root_lock(qdisc) and BH! */
+/* Under qdisc_lock(qdisc) and BH! */
 
 void qdisc_reset(struct Qdisc *qdisc)
 {
@@ -515,18 +584,33 @@ void qdisc_reset(struct Qdisc *qdisc)
 
 	if (ops->reset)
 		ops->reset(qdisc);
+
+	if (qdisc->gso_skb) {
+		kfree_skb(qdisc->gso_skb);
+		qdisc->gso_skb = NULL;
+		qdisc->q.qlen = 0;
+	}
 }
 EXPORT_SYMBOL(qdisc_reset);
 
-/* this is the rcu callback function to clean up a qdisc when there
- * are no further references to it */
+static void qdisc_rcu_free(struct rcu_head *head)
+{
+	struct Qdisc *qdisc = container_of(head, struct Qdisc, rcu_head);
+
+	kfree((char *) qdisc - qdisc->padded);
+}
 
-static void __qdisc_destroy(struct rcu_head *head)
+void qdisc_destroy(struct Qdisc *qdisc)
 {
-	struct Qdisc *qdisc = container_of(head, struct Qdisc, q_rcu);
 	const struct Qdisc_ops  *ops = qdisc->ops;
 
+	if (qdisc->flags & TCQ_F_BUILTIN ||
+	    !atomic_dec_and_test(&qdisc->refcnt))
+		return;
+
 #ifdef CONFIG_NET_SCHED
+	qdisc_list_del(qdisc);
+
 	qdisc_put_stab(qdisc->stab);
 #endif
 	gen_kill_estimator(&qdisc->bstats, &qdisc->rate_est);
@@ -539,36 +623,37 @@ static void __qdisc_destroy(struct rcu_head *head)
 	dev_put(qdisc_dev(qdisc));
 
 	kfree_skb(qdisc->gso_skb);
-
-	kfree((char *) qdisc - qdisc->padded);
+	/*
+	 * gen_estimator est_timer() might access qdisc->q.lock,
+	 * wait a RCU grace period before freeing qdisc.
+	 */
+	call_rcu(&qdisc->rcu_head, qdisc_rcu_free);
 }
+EXPORT_SYMBOL(qdisc_destroy);
 
-/* Under qdisc_root_lock(qdisc) and BH! */
-
-void qdisc_destroy(struct Qdisc *qdisc)
+/* Attach toplevel qdisc to device queue. */
+struct Qdisc *dev_graft_qdisc(struct netdev_queue *dev_queue,
+			      struct Qdisc *qdisc)
 {
-	if (qdisc->flags & TCQ_F_BUILTIN ||
-	    !atomic_dec_and_test(&qdisc->refcnt))
-		return;
+	struct Qdisc *oqdisc = dev_queue->qdisc_sleeping;
+	spinlock_t *root_lock;
 
-	if (qdisc->parent)
-		list_del(&qdisc->list);
+	root_lock = qdisc_lock(oqdisc);
+	spin_lock_bh(root_lock);
 
-	call_rcu(&qdisc->q_rcu, __qdisc_destroy);
-}
-EXPORT_SYMBOL(qdisc_destroy);
+	/* Prune old scheduler */
+	if (oqdisc && atomic_read(&oqdisc->refcnt) <= 1)
+		qdisc_reset(oqdisc);
 
-static bool dev_all_qdisc_sleeping_noop(struct net_device *dev)
-{
-	unsigned int i;
+	/* ... and graft new one */
+	if (qdisc == NULL)
+		qdisc = &noop_qdisc;
+	dev_queue->qdisc_sleeping = qdisc;
+	rcu_assign_pointer(dev_queue->qdisc, &noop_qdisc);
 
-	for (i = 0; i < dev->num_tx_queues; i++) {
-		struct netdev_queue *txq = netdev_get_tx_queue(dev, i);
+	spin_unlock_bh(root_lock);
 
-		if (txq->qdisc_sleeping != &noop_qdisc)
-			return false;
-	}
-	return true;
+	return oqdisc;
 }
 
 static void attach_one_default_qdisc(struct net_device *dev,
@@ -584,12 +669,35 @@ static void attach_one_default_qdisc(struct net_device *dev,
 			printk(KERN_INFO "%s: activation failed\n", dev->name);
 			return;
 		}
+
+		/* Can by-pass the queue discipline for default qdisc */
+		qdisc->flags |= TCQ_F_CAN_BYPASS;
 	} else {
 		qdisc =  &noqueue_qdisc;
 	}
 	dev_queue->qdisc_sleeping = qdisc;
 }
 
+static void attach_default_qdiscs(struct net_device *dev)
+{
+	struct netdev_queue *txq;
+	struct Qdisc *qdisc;
+
+	txq = netdev_get_tx_queue(dev, 0);
+
+	if (!netif_is_multiqueue(dev) || dev->tx_queue_len == 0) {
+		netdev_for_each_tx_queue(dev, attach_one_default_qdisc, NULL);
+		dev->qdisc = txq->qdisc_sleeping;
+		atomic_inc(&dev->qdisc->refcnt);
+	} else {
+		qdisc = qdisc_create_dflt(dev, txq, &mq_qdisc_ops, TC_H_ROOT);
+		if (qdisc) {
+			qdisc->ops->attach(qdisc);
+			dev->qdisc = qdisc;
+		}
+	}
+}
+
 static void transition_one_qdisc(struct net_device *dev,
 				 struct netdev_queue *dev_queue,
 				 void *_need_watchdog)
@@ -597,9 +705,14 @@ static void transition_one_qdisc(struct net_device *dev,
 	struct Qdisc *new_qdisc = dev_queue->qdisc_sleeping;
 	int *need_watchdog_p = _need_watchdog;
 
+	if (!(new_qdisc->flags & TCQ_F_BUILTIN))
+		clear_bit(__QDISC_STATE_DEACTIVATED, &new_qdisc->state);
+
 	rcu_assign_pointer(dev_queue->qdisc, new_qdisc);
-	if (need_watchdog_p && new_qdisc != &noqueue_qdisc)
+	if (need_watchdog_p && new_qdisc != &noqueue_qdisc) {
+		dev_queue->trans_start = 0;
 		*need_watchdog_p = 1;
+	}
 }
 
 void dev_activate(struct net_device *dev)
@@ -612,8 +725,8 @@ void dev_activate(struct net_device *dev)
 	   virtual interfaces
 	 */
 
-	if (dev_all_qdisc_sleeping_noop(dev))
-		netdev_for_each_tx_queue(dev, attach_one_default_qdisc, NULL);
+	if (dev->qdisc == &noop_qdisc)
+		attach_default_qdiscs(dev);
 
 	if (!netif_carrier_ok(dev))
 		/* Delay activation until next carrier-on event */
@@ -640,14 +753,17 @@ static void dev_deactivate_queue(struct net_device *dev,
 	if (qdisc) {
 		spin_lock_bh(qdisc_lock(qdisc));
 
-		dev_queue->qdisc = qdisc_default;
+		if (!(qdisc->flags & TCQ_F_BUILTIN))
+			set_bit(__QDISC_STATE_DEACTIVATED, &qdisc->state);
+
+		rcu_assign_pointer(dev_queue->qdisc, qdisc_default);
 		qdisc_reset(qdisc);
 
 		spin_unlock_bh(qdisc_lock(qdisc));
 	}
 }
 
-static bool some_qdisc_is_running(struct net_device *dev, int lock)
+static bool some_qdisc_is_busy(struct net_device *dev)
 {
 	unsigned int i;
 
@@ -658,16 +774,15 @@ static bool some_qdisc_is_running(struct net_device *dev, int lock)
 		int val;
 
 		dev_queue = netdev_get_tx_queue(dev, i);
-		q = dev_queue->qdisc;
-		root_lock = qdisc_root_lock(q);
+		q = dev_queue->qdisc_sleeping;
+		root_lock = qdisc_lock(q);
 
-		if (lock)
-			spin_lock_bh(root_lock);
+		spin_lock_bh(root_lock);
 
-		val = test_bit(__QDISC_STATE_RUNNING, &q->state);
+		val = (test_bit(__QDISC_STATE_RUNNING, &q->state) ||
+		       test_bit(__QDISC_STATE_SCHED, &q->state));
 
-		if (lock)
-			spin_unlock_bh(root_lock);
+		spin_unlock_bh(root_lock);
 
 		if (val)
 			return true;
@@ -677,8 +792,6 @@ static bool some_qdisc_is_running(struct net_device *dev, int lock)
 
 void dev_deactivate(struct net_device *dev)
 {
-	bool running;
-
 	netdev_for_each_tx_queue(dev, dev_deactivate_queue, &noop_qdisc);
 	dev_deactivate_queue(dev, &dev->rx_queue, &noop_qdisc);
 
@@ -688,25 +801,8 @@ void dev_deactivate(struct net_device *dev)
 	synchronize_rcu();
 
 	/* Wait for outstanding qdisc_run calls. */
-	do {
-		while (some_qdisc_is_running(dev, 0))
-			yield();
-
-		/*
-		 * Double-check inside queue lock to ensure that all effects
-		 * of the queue run are visible when we return.
-		 */
-		running = some_qdisc_is_running(dev, 1);
-
-		/*
-		 * The running flag should never be set at this point because
-		 * we've already set dev->qdisc to noop_qdisc *inside* the same
-		 * pair of spin locks.  That is, if any qdisc_run starts after
-		 * our initial test it should see the noop_qdisc and then
-		 * clear the RUNNING bit before dropping the queue lock.  So
-		 * if it is set here then we've found a bug.
-		 */
-	} while (WARN_ON_ONCE(running));
+	while (some_qdisc_is_busy(dev))
+		yield();
 }
 
 static void dev_init_scheduler_queue(struct net_device *dev,
@@ -721,6 +817,7 @@ static void dev_init_scheduler_queue(struct net_device *dev,
 
 void dev_init_scheduler(struct net_device *dev)
 {
+	dev->qdisc = &noop_qdisc;
 	netdev_for_each_tx_queue(dev, dev_init_scheduler_queue, &noop_qdisc);
 	dev_init_scheduler_queue(dev, &dev->rx_queue, &noop_qdisc);
 
@@ -735,14 +832,10 @@ static void shutdown_scheduler_queue(struct net_device *dev,
 	struct Qdisc *qdisc_default = _qdisc_default;
 
 	if (qdisc) {
-		spinlock_t *root_lock = qdisc_root_lock(qdisc);
-
-		dev_queue->qdisc = qdisc_default;
+		rcu_assign_pointer(dev_queue->qdisc, qdisc_default);
 		dev_queue->qdisc_sleeping = qdisc_default;
 
-		spin_lock_bh(root_lock);
 		qdisc_destroy(qdisc);
-		spin_unlock_bh(root_lock);
 	}
 }
 
@@ -750,5 +843,8 @@ void dev_shutdown(struct net_device *dev)
 {
 	netdev_for_each_tx_queue(dev, shutdown_scheduler_queue, &noop_qdisc);
 	shutdown_scheduler_queue(dev, &dev->rx_queue, &noop_qdisc);
+	qdisc_destroy(dev->qdisc);
+	dev->qdisc = &noop_qdisc;
+
 	WARN_ON(timer_pending(&dev->watchdog_timer));
 }