/* Main transmission queue. */
/* Modifications to data participating in scheduling must be protected with
- * queue->lock spinlock.
+ * qdisc_root_lock(qdisc) spinlock.
*
* The idea is the following:
- * - enqueue, dequeue are serialized via top level device
- * spinlock queue->lock.
- * - ingress filtering is serialized via top level device
- * spinlock dev->rx_queue.lock.
+ * - enqueue, dequeue are serialized via qdisc root lock
+ * - ingress filtering is also serialized via qdisc root lock
* - updates to tree and tree walking are only done under the rtnl mutex.
*/
-void qdisc_lock_tree(struct net_device *dev)
- __acquires(dev->tx_queue.lock)
- __acquires(dev->rx_queue.lock)
-{
- spin_lock_bh(&dev->tx_queue.lock);
- spin_lock(&dev->rx_queue.lock);
-}
-EXPORT_SYMBOL(qdisc_lock_tree);
-
-void qdisc_unlock_tree(struct net_device *dev)
- __releases(dev->rx_queue.lock)
- __releases(dev->tx_queue.lock)
-{
- spin_unlock(&dev->rx_queue.lock);
- spin_unlock_bh(&dev->tx_queue.lock);
-}
-EXPORT_SYMBOL(qdisc_unlock_tree);
-
static inline int qdisc_qlen(struct Qdisc *q)
{
return q->q.qlen;
}
-static inline int dev_requeue_skb(struct sk_buff *skb,
- struct netdev_queue *dev_queue,
- struct Qdisc *q)
+static inline int dev_requeue_skb(struct sk_buff *skb, struct Qdisc *q)
{
if (unlikely(skb->next))
- dev_queue->gso_skb = skb;
+ q->gso_skb = skb;
else
q->ops->requeue(skb, q);
- netif_schedule_queue(dev_queue);
+ __netif_schedule(q);
return 0;
}
-static inline struct sk_buff *dequeue_skb(struct netdev_queue *dev_queue,
- struct Qdisc *q)
+static inline struct sk_buff *dequeue_skb(struct Qdisc *q)
{
struct sk_buff *skb;
- if ((skb = dev_queue->gso_skb))
- dev_queue->gso_skb = NULL;
+ if ((skb = q->gso_skb))
+ q->gso_skb = NULL;
else
skb = q->dequeue(q);
struct netdev_queue *dev_queue,
struct Qdisc *q)
{
- struct net_device *dev = dev_queue->dev;
int ret;
- if (unlikely(dev->xmit_lock_owner == smp_processor_id())) {
+ if (unlikely(dev_queue->xmit_lock_owner == smp_processor_id())) {
/*
* Same CPU holding the lock. It may be a transient
* configuration error, when hard_start_xmit() recurses. We
kfree_skb(skb);
if (net_ratelimit())
printk(KERN_WARNING "Dead loop on netdevice %s, "
- "fix it urgently!\n", dev->name);
+ "fix it urgently!\n", dev_queue->dev->name);
ret = qdisc_qlen(q);
} else {
/*
* some time.
*/
__get_cpu_var(netdev_rx_stat).cpu_collision++;
- ret = dev_requeue_skb(skb, dev_queue, q);
+ ret = dev_requeue_skb(skb, q);
}
return ret;
}
/*
- * NOTE: Called under queue->lock with locally disabled BH.
+ * NOTE: Called under qdisc_lock(q) with locally disabled BH.
*
- * __LINK_STATE_QDISC_RUNNING guarantees only one CPU can process this
- * device at a time. queue->lock serializes queue accesses for
- * this device AND txq->qdisc pointer itself.
+ * __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.
*
- * queue->lock and netif_tx_lock are mutually exclusive,
+ * 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
* >0 - queue is not empty.
*
*/
-static inline int qdisc_restart(struct netdev_queue *txq)
+static inline int qdisc_restart(struct Qdisc *q)
{
- struct Qdisc *q = txq->qdisc;
+ 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(txq, q)) == NULL))
+ if (unlikely((skb = dequeue_skb(q)) == NULL))
return 0;
+ root_lock = qdisc_root_lock(q);
- /* And release queue */
- spin_unlock(&txq->lock);
+ /* And release qdisc */
+ spin_unlock(root_lock);
- dev = txq->dev;
+ dev = qdisc_dev(q);
+ txq = netdev_get_tx_queue(dev, skb_get_queue_mapping(skb));
- HARD_TX_LOCK(dev, smp_processor_id());
+ HARD_TX_LOCK(dev, txq, smp_processor_id());
if (!netif_subqueue_stopped(dev, skb))
- ret = dev_hard_start_xmit(skb, dev);
- HARD_TX_UNLOCK(dev);
+ ret = dev_hard_start_xmit(skb, dev, txq);
+ HARD_TX_UNLOCK(dev, txq);
- spin_lock(&txq->lock);
- q = txq->qdisc;
+ spin_lock(root_lock);
switch (ret) {
case NETDEV_TX_OK:
printk(KERN_WARNING "BUG %s code %d qlen %d\n",
dev->name, ret, q->q.qlen);
- ret = dev_requeue_skb(skb, txq, q);
+ ret = dev_requeue_skb(skb, q);
break;
}
+ if (ret && netif_tx_queue_stopped(txq))
+ ret = 0;
+
return ret;
}
-void __qdisc_run(struct netdev_queue *txq)
+void __qdisc_run(struct Qdisc *q)
{
- struct net_device *dev = txq->dev;
unsigned long start_time = jiffies;
- while (qdisc_restart(txq)) {
- if (netif_queue_stopped(dev))
- break;
-
+ while (qdisc_restart(q)) {
/*
* Postpone processing if
* 1. another process needs the CPU;
* 2. we've been doing it for too long.
*/
if (need_resched() || jiffies != start_time) {
- netif_schedule_queue(txq);
+ __netif_schedule(q);
break;
}
}
- clear_bit(__LINK_STATE_QDISC_RUNNING, &dev->state);
+ clear_bit(__QDISC_STATE_RUNNING, &q->state);
}
static void dev_watchdog(unsigned long arg)
{
struct net_device *dev = (struct net_device *)arg;
- struct netdev_queue *txq = &dev->tx_queue;
netif_tx_lock(dev);
- if (txq->qdisc != &noop_qdisc) {
+ if (!qdisc_tx_is_noop(dev)) {
if (netif_device_present(dev) &&
netif_running(dev) &&
netif_carrier_ok(dev)) {
- if (netif_queue_stopped(dev) &&
- time_after(jiffies, dev->trans_start + dev->watchdog_timeo)) {
+ int some_queue_stopped = 0;
+ unsigned int i;
+
+ for (i = 0; i < dev->num_tx_queues; i++) {
+ struct netdev_queue *txq;
- printk(KERN_INFO "NETDEV WATCHDOG: %s: transmit timed out\n",
- dev->name);
+ txq = netdev_get_tx_queue(dev, i);
+ if (netif_tx_queue_stopped(txq)) {
+ some_queue_stopped = 1;
+ break;
+ }
+ }
+
+ if (some_queue_stopped &&
+ time_after(jiffies, (dev->trans_start +
+ dev->watchdog_timeo))) {
+ 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);
}
- if (!mod_timer(&dev->watchdog_timer, round_jiffies(jiffies + dev->watchdog_timeo)))
+ if (!mod_timer(&dev->watchdog_timer,
+ round_jiffies(jiffies +
+ dev->watchdog_timeo)))
dev_hold(dev);
}
}
.owner = THIS_MODULE,
};
+static struct netdev_queue noop_netdev_queue = {
+ .qdisc = &noop_qdisc,
+};
+
struct Qdisc noop_qdisc = {
.enqueue = noop_enqueue,
.dequeue = noop_dequeue,
.flags = TCQ_F_BUILTIN,
.ops = &noop_qdisc_ops,
.list = LIST_HEAD_INIT(noop_qdisc.list),
+ .q.lock = __SPIN_LOCK_UNLOCKED(noop_qdisc.q.lock),
+ .dev_queue = &noop_netdev_queue,
};
EXPORT_SYMBOL(noop_qdisc);
.owner = THIS_MODULE,
};
+static struct Qdisc noqueue_qdisc;
+static struct netdev_queue noqueue_netdev_queue = {
+ .qdisc = &noqueue_qdisc,
+};
+
static struct Qdisc noqueue_qdisc = {
.enqueue = NULL,
.dequeue = noop_dequeue,
.flags = TCQ_F_BUILTIN,
.ops = &noqueue_qdisc_ops,
.list = LIST_HEAD_INIT(noqueue_qdisc.list),
+ .q.lock = __SPIN_LOCK_UNLOCKED(noqueue_qdisc.q.lock),
+ .dev_queue = &noqueue_netdev_queue,
};
}
EXPORT_SYMBOL(qdisc_create_dflt);
-/* Under queue->lock and BH! */
+/* Under qdisc_root_lock(qdisc) and BH! */
void qdisc_reset(struct Qdisc *qdisc)
{
static void __qdisc_destroy(struct rcu_head *head)
{
struct Qdisc *qdisc = container_of(head, struct Qdisc, q_rcu);
+ const struct Qdisc_ops *ops = qdisc->ops;
+
+#ifdef CONFIG_NET_SCHED
+ qdisc_put_stab(qdisc->stab);
+#endif
+ gen_kill_estimator(&qdisc->bstats, &qdisc->rate_est);
+ if (ops->reset)
+ ops->reset(qdisc);
+ if (ops->destroy)
+ ops->destroy(qdisc);
+
+ module_put(ops->owner);
+ dev_put(qdisc_dev(qdisc));
+
+ kfree_skb(qdisc->gso_skb);
+
kfree((char *) qdisc - qdisc->padded);
}
-/* Under queue->lock and BH! */
+/* Under qdisc_root_lock(qdisc) and BH! */
void qdisc_destroy(struct Qdisc *qdisc)
{
- const struct Qdisc_ops *ops = qdisc->ops;
-
if (qdisc->flags & TCQ_F_BUILTIN ||
!atomic_dec_and_test(&qdisc->refcnt))
return;
- list_del(&qdisc->list);
- gen_kill_estimator(&qdisc->bstats, &qdisc->rate_est);
- if (ops->reset)
- ops->reset(qdisc);
- if (ops->destroy)
- ops->destroy(qdisc);
+ if (qdisc->parent)
+ list_del(&qdisc->list);
- module_put(ops->owner);
- dev_put(qdisc_dev(qdisc));
call_rcu(&qdisc->q_rcu, __qdisc_destroy);
}
EXPORT_SYMBOL(qdisc_destroy);
+static bool dev_all_qdisc_sleeping_noop(struct net_device *dev)
+{
+ unsigned int i;
+
+ for (i = 0; i < dev->num_tx_queues; i++) {
+ struct netdev_queue *txq = netdev_get_tx_queue(dev, i);
+
+ if (txq->qdisc_sleeping != &noop_qdisc)
+ return false;
+ }
+ return true;
+}
+
+static void attach_one_default_qdisc(struct net_device *dev,
+ struct netdev_queue *dev_queue,
+ void *_unused)
+{
+ struct Qdisc *qdisc;
+
+ if (dev->tx_queue_len) {
+ qdisc = qdisc_create_dflt(dev, dev_queue,
+ &pfifo_fast_ops, TC_H_ROOT);
+ if (!qdisc) {
+ printk(KERN_INFO "%s: activation failed\n", dev->name);
+ return;
+ }
+ } else {
+ qdisc = &noqueue_qdisc;
+ }
+ dev_queue->qdisc_sleeping = qdisc;
+}
+
+static void transition_one_qdisc(struct net_device *dev,
+ struct netdev_queue *dev_queue,
+ void *_need_watchdog)
+{
+ struct Qdisc *new_qdisc = dev_queue->qdisc_sleeping;
+ int *need_watchdog_p = _need_watchdog;
+
+ rcu_assign_pointer(dev_queue->qdisc, new_qdisc);
+ if (new_qdisc != &noqueue_qdisc)
+ *need_watchdog_p = 1;
+}
+
void dev_activate(struct net_device *dev)
{
- struct netdev_queue *txq = &dev->tx_queue;
+ int need_watchdog;
/* No queueing discipline is attached to device;
create default one i.e. pfifo_fast for devices,
virtual interfaces
*/
- if (txq->qdisc_sleeping == &noop_qdisc) {
- struct Qdisc *qdisc;
- if (dev->tx_queue_len) {
- qdisc = qdisc_create_dflt(dev, txq,
- &pfifo_fast_ops,
- TC_H_ROOT);
- if (qdisc == NULL) {
- printk(KERN_INFO "%s: activation failed\n", dev->name);
- return;
- }
- list_add_tail(&qdisc->list, &txq->qdisc_list);
- } else {
- qdisc = &noqueue_qdisc;
- }
- txq->qdisc_sleeping = qdisc;
- }
+ if (dev_all_qdisc_sleeping_noop(dev))
+ netdev_for_each_tx_queue(dev, attach_one_default_qdisc, NULL);
if (!netif_carrier_ok(dev))
/* Delay activation until next carrier-on event */
return;
- spin_lock_bh(&txq->lock);
- rcu_assign_pointer(txq->qdisc, txq->qdisc_sleeping);
- if (txq->qdisc != &noqueue_qdisc) {
+ need_watchdog = 0;
+ netdev_for_each_tx_queue(dev, transition_one_qdisc, &need_watchdog);
+
+ if (need_watchdog) {
dev->trans_start = jiffies;
dev_watchdog_up(dev);
}
- spin_unlock_bh(&txq->lock);
}
-static void dev_deactivate_queue(struct netdev_queue *dev_queue,
- struct Qdisc *qdisc_default)
+static void dev_deactivate_queue(struct net_device *dev,
+ struct netdev_queue *dev_queue,
+ void *_qdisc_default)
{
+ struct Qdisc *qdisc_default = _qdisc_default;
struct Qdisc *qdisc;
- struct sk_buff *skb;
-
- spin_lock_bh(&dev_queue->lock);
qdisc = dev_queue->qdisc;
if (qdisc) {
+ spin_lock_bh(qdisc_lock(qdisc));
+
dev_queue->qdisc = qdisc_default;
qdisc_reset(qdisc);
+
+ spin_unlock_bh(qdisc_lock(qdisc));
}
- skb = dev_queue->gso_skb;
- dev_queue->gso_skb = NULL;
+}
- spin_unlock_bh(&dev_queue->lock);
+static bool some_qdisc_is_running(struct net_device *dev, int lock)
+{
+ unsigned int i;
- kfree_skb(skb);
+ for (i = 0; i < dev->num_tx_queues; i++) {
+ struct netdev_queue *dev_queue;
+ spinlock_t *root_lock;
+ struct Qdisc *q;
+ int val;
+
+ dev_queue = netdev_get_tx_queue(dev, i);
+ q = dev_queue->qdisc;
+ root_lock = qdisc_root_lock(q);
+
+ if (lock)
+ spin_lock_bh(root_lock);
+
+ val = test_bit(__QDISC_STATE_RUNNING, &q->state);
+
+ if (lock)
+ spin_unlock_bh(root_lock);
+
+ if (val)
+ return true;
+ }
+ return false;
}
void dev_deactivate(struct net_device *dev)
{
- int running;
+ bool running;
- dev_deactivate_queue(&dev->tx_queue, &noop_qdisc);
+ netdev_for_each_tx_queue(dev, dev_deactivate_queue, &noop_qdisc);
dev_watchdog_down(dev);
/* Wait for outstanding qdisc_run calls. */
do {
- while (test_bit(__LINK_STATE_QDISC_RUNNING, &dev->state))
+ 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.
*/
- spin_lock_bh(&dev->tx_queue.lock);
- running = test_bit(__LINK_STATE_QDISC_RUNNING, &dev->state);
- spin_unlock_bh(&dev->tx_queue.lock);
+ running = some_qdisc_is_running(dev, 1);
/*
* The running flag should never be set at this point because
static void dev_init_scheduler_queue(struct net_device *dev,
struct netdev_queue *dev_queue,
- struct Qdisc *qdisc)
+ void *_qdisc)
{
+ struct Qdisc *qdisc = _qdisc;
+
dev_queue->qdisc = qdisc;
dev_queue->qdisc_sleeping = qdisc;
- INIT_LIST_HEAD(&dev_queue->qdisc_list);
}
void dev_init_scheduler(struct net_device *dev)
{
- qdisc_lock_tree(dev);
- dev_init_scheduler_queue(dev, &dev->tx_queue, &noop_qdisc);
+ netdev_for_each_tx_queue(dev, dev_init_scheduler_queue, &noop_qdisc);
dev_init_scheduler_queue(dev, &dev->rx_queue, NULL);
- qdisc_unlock_tree(dev);
setup_timer(&dev->watchdog_timer, dev_watchdog, (unsigned long)dev);
}
-static void dev_shutdown_scheduler_queue(struct net_device *dev,
- struct netdev_queue *dev_queue,
- struct Qdisc *qdisc_default)
+static void shutdown_scheduler_queue(struct net_device *dev,
+ struct netdev_queue *dev_queue,
+ void *_qdisc_default)
{
struct Qdisc *qdisc = dev_queue->qdisc_sleeping;
+ struct Qdisc *qdisc_default = _qdisc_default;
if (qdisc) {
+ spinlock_t *root_lock = qdisc_root_lock(qdisc);
+
dev_queue->qdisc = qdisc_default;
dev_queue->qdisc_sleeping = qdisc_default;
+ spin_lock(root_lock);
qdisc_destroy(qdisc);
+ spin_unlock(root_lock);
}
}
void dev_shutdown(struct net_device *dev)
{
- qdisc_lock_tree(dev);
- dev_shutdown_scheduler_queue(dev, &dev->tx_queue, &noop_qdisc);
- dev_shutdown_scheduler_queue(dev, &dev->rx_queue, NULL);
+ netdev_for_each_tx_queue(dev, shutdown_scheduler_queue, &noop_qdisc);
+ shutdown_scheduler_queue(dev, &dev->rx_queue, NULL);
BUG_TRAP(!timer_pending(&dev->watchdog_timer));
- qdisc_unlock_tree(dev);
}