diff options
Diffstat (limited to 'net/sched/sch_generic.c')
| -rw-r--r-- | net/sched/sch_generic.c | 802 |
1 files changed, 551 insertions, 251 deletions
diff --git a/net/sched/sch_generic.c b/net/sched/sch_generic.c index b741618e4d5..e1543b03e39 100644 --- a/net/sched/sch_generic.c +++ b/net/sched/sch_generic.c @@ -24,76 +24,66 @@ #include <linux/init.h> #include <linux/rcupdate.h> #include <linux/list.h> +#include <linux/slab.h> +#include <linux/if_vlan.h> +#include <net/sch_generic.h> #include <net/pkt_sched.h> +#include <net/dst.h> + +/* Qdisc to use by default */ +const struct Qdisc_ops *default_qdisc_ops = &pfifo_fast_ops; +EXPORT_SYMBOL(default_qdisc_ops); /* Main transmission queue. */ /* Modifications to data participating in scheduling must be protected with - * dev->queue_lock spinlock. + * qdisc_lock(qdisc) spinlock. * * The idea is the following: - * - enqueue, dequeue are serialized via top level device - * spinlock dev->queue_lock. - * - ingress filtering is serialized via top level device - * spinlock dev->ingress_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->queue_lock) - __acquires(dev->ingress_lock) -{ - spin_lock_bh(&dev->queue_lock); - spin_lock(&dev->ingress_lock); -} -EXPORT_SYMBOL(qdisc_lock_tree); - -void qdisc_unlock_tree(struct net_device *dev) - __releases(dev->ingress_lock) - __releases(dev->queue_lock) -{ - spin_unlock(&dev->ingress_lock); - spin_unlock_bh(&dev->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 net_device *dev, - struct Qdisc *q) +static inline int dev_requeue_skb(struct sk_buff *skb, struct Qdisc *q) { - if (unlikely(skb->next)) - dev->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); - netif_schedule(dev); return 0; } -static inline struct sk_buff *dev_dequeue_skb(struct net_device *dev, - struct Qdisc *q) +static inline struct sk_buff *dequeue_skb(struct Qdisc *q) { - struct sk_buff *skb; + struct sk_buff *skb = q->gso_skb; + const struct netdev_queue *txq = q->dev_queue; - if ((skb = dev->gso_skb)) - dev->gso_skb = NULL; - else - skb = q->dequeue(q); + if (unlikely(skb)) { + /* check the reason of requeuing without tx lock first */ + txq = netdev_get_tx_queue(txq->dev, skb_get_queue_mapping(skb)); + if (!netif_xmit_frozen_or_stopped(txq)) { + q->gso_skb = NULL; + q->q.qlen--; + } else + skb = NULL; + } else { + if (!(q->flags & TCQ_F_ONETXQUEUE) || !netif_xmit_frozen_or_stopped(txq)) + skb = q->dequeue(q); + } return skb; } static inline int handle_dev_cpu_collision(struct sk_buff *skb, - struct net_device *dev, + struct netdev_queue *dev_queue, struct Qdisc *q) { 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 @@ -101,126 +91,182 @@ static inline int handle_dev_cpu_collision(struct sk_buff *skb, * deadloop is detected. Return OK to try the next skb. */ kfree_skb(skb); - if (net_ratelimit()) - printk(KERN_WARNING "Dead loop on netdevice %s, " - "fix it urgently!\n", dev->name); + net_warn_ratelimited("Dead loop on netdevice %s, fix it urgently!\n", + dev_queue->dev->name); ret = qdisc_qlen(q); } else { /* * Another cpu is holding lock, requeue & delay xmits for * some time. */ - __get_cpu_var(netdev_rx_stat).cpu_collision++; - ret = dev_requeue_skb(skb, dev, q); + __this_cpu_inc(softnet_data.cpu_collision); + ret = dev_requeue_skb(skb, q); } return ret; } /* - * NOTE: Called under dev->queue_lock with locally disabled BH. - * - * __LINK_STATE_QDISC_RUNNING guarantees only one CPU can process this - * device at a time. dev->queue_lock serializes queue accesses for - * this device AND dev->qdisc pointer itself. - * - * netif_tx_lock serializes accesses to device driver. - * - * dev->queue_lock 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 net_device *dev) +int sch_direct_xmit(struct sk_buff *skb, struct Qdisc *q, + struct net_device *dev, struct netdev_queue *txq, + spinlock_t *root_lock) { - struct Qdisc *q = dev->qdisc; - struct sk_buff *skb; int ret = NETDEV_TX_BUSY; - /* Dequeue packet */ - if (unlikely((skb = dev_dequeue_skb(dev, q)) == NULL)) - return 0; - + /* And release qdisc */ + spin_unlock(root_lock); - /* And release queue */ - spin_unlock(&dev->queue_lock); + HARD_TX_LOCK(dev, txq, smp_processor_id()); + if (!netif_xmit_frozen_or_stopped(txq)) + ret = dev_hard_start_xmit(skb, dev, txq); - HARD_TX_LOCK(dev, smp_processor_id()); - if (!netif_subqueue_stopped(dev, skb)) - ret = dev_hard_start_xmit(skb, dev); - HARD_TX_UNLOCK(dev); + HARD_TX_UNLOCK(dev, txq); - spin_lock(&dev->queue_lock); - q = dev->qdisc; + 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, dev, q); - break; - - default: + ret = handle_dev_cpu_collision(skb, txq, q); + } 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); + if (unlikely(ret != NETDEV_TX_BUSY)) + net_warn_ratelimited("BUG %s code %d qlen %d\n", + dev->name, ret, q->q.qlen); - ret = dev_requeue_skb(skb, dev, q); - break; + ret = dev_requeue_skb(skb, q); } + if (ret && netif_xmit_frozen_or_stopped(txq)) + ret = 0; + return ret; } -void __qdisc_run(struct net_device *dev) +/* + * 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) { - unsigned long start_time = jiffies; + struct netdev_queue *txq; + struct net_device *dev; + spinlock_t *root_lock; + struct sk_buff *skb; - while (qdisc_restart(dev)) { - if (netif_queue_stopped(dev)) - break; + /* 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) +{ + int quota = weight_p; + + while (qdisc_restart(q)) { /* - * Postpone processing if - * 1. another process needs the CPU; - * 2. we've been doing it for too long. + * Ordered by possible occurrence: Postpone processing if + * 1. we've exceeded packet quota + * 2. another process needs the CPU; */ - if (need_resched() || jiffies != start_time) { - netif_schedule(dev); + if (--quota <= 0 || need_resched()) { + __netif_schedule(q); break; } } - clear_bit(__LINK_STATE_QDISC_RUNNING, &dev->state); + qdisc_run_end(q); +} + +unsigned long dev_trans_start(struct net_device *dev) +{ + unsigned long val, res; + unsigned int i; + + if (is_vlan_dev(dev)) + dev = vlan_dev_real_dev(dev); + res = dev->trans_start; + 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; netif_tx_lock(dev); - if (dev->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_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); + /* + * old device drivers set dev->trans_start + */ + trans_start = txq->trans_start ? : dev->trans_start; + if (netif_xmit_stopped(txq) && + time_after(jiffies, (trans_start + + dev->watchdog_timeo))) { + some_queue_timedout = 1; + txq->trans_timeout++; + break; + } + } - printk(KERN_INFO "NETDEV WATCHDOG: %s: transmit timed out\n", - dev->name); - dev->tx_timeout(dev); + if (some_queue_timedout) { + WARN_ONCE(1, KERN_INFO "NETDEV WATCHDOG: %s (%s): transmit queue %u timed out\n", + dev->name, netdev_drivername(dev), i); + dev->netdev_ops->ndo_tx_timeout(dev); } - 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); } } @@ -231,7 +277,7 @@ 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, @@ -262,6 +308,9 @@ 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; + atomic_inc(&dev->carrier_changes); linkwatch_fire_event(dev); if (netif_running(dev)) __netdev_watchdog_up(dev); @@ -277,8 +326,12 @@ 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; + atomic_inc(&dev->carrier_changes); linkwatch_fire_event(dev); + } } EXPORT_SYMBOL(netif_carrier_off); @@ -287,41 +340,40 @@ EXPORT_SYMBOL(netif_carrier_off); cheaper. */ -static int noop_enqueue(struct sk_buff *skb, struct Qdisc * qdisc) +static int noop_enqueue(struct sk_buff *skb, struct Qdisc *qdisc) { kfree_skb(skb); return NET_XMIT_CN; } -static struct sk_buff *noop_dequeue(struct Qdisc * qdisc) +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 = { .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, + .busylock = __SPIN_LOCK_UNLOCKED(noop_qdisc.busylock), }; EXPORT_SYMBOL(noop_qdisc); @@ -330,21 +382,31 @@ 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 = { .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, + .busylock = __SPIN_LOCK_UNLOCKED(noqueue_qdisc.busylock), }; -static const u8 prio2band[TC_PRIO_MAX+1] = - { 1, 2, 2, 2, 1, 2, 0, 0 , 1, 1, 1, 1, 1, 1, 1, 1 }; +static const u8 prio2band[TC_PRIO_MAX + 1] = { + 1, 2, 2, 2, 1, 2, 0, 0 , 1, 1, 1, 1, 1, 1, 1, 1 +}; /* 3-band FIFO queue: old style, but should be a bit faster than generic prio+fifo combination. @@ -352,18 +414,38 @@ 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) +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->tx_queue_len) { + priv->bitmap |= (1 << band); qdisc->q.qlen++; return __qdisc_enqueue_tail(skb, qdisc, list); } @@ -371,35 +453,48 @@ static int pfifo_fast_enqueue(struct sk_buff *skb, struct Qdisc* qdisc) return qdisc_drop(skb, qdisc); } -static struct sk_buff *pfifo_fast_dequeue(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) +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; } @@ -408,8 +503,9 @@ static int pfifo_fast_dump(struct Qdisc *qdisc, struct sk_buff *skb) { struct tc_prio_qopt opt = { .bands = PFIFO_FAST_BANDS }; - memcpy(&opt.priomap, prio2band, TC_PRIO_MAX+1); - NLA_PUT(skb, TCA_OPTIONS, sizeof(opt), &opt); + memcpy(&opt.priomap, prio2band, TC_PRIO_MAX + 1); + if (nla_put(skb, TCA_OPTIONS, sizeof(opt), &opt)) + goto nla_put_failure; return skb->len; nla_put_failure: @@ -419,66 +515,86 @@ 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)); + /* Can by-pass the queue discipline */ + qdisc->flags |= TCQ_F_CAN_BYPASS; 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, .owner = THIS_MODULE, }; -struct Qdisc *qdisc_alloc(struct net_device *dev, struct Qdisc_ops *ops) +static struct lock_class_key qdisc_tx_busylock; + +struct Qdisc *qdisc_alloc(struct netdev_queue *dev_queue, + const struct Qdisc_ops *ops) { void *p; struct Qdisc *sch; - unsigned int size; + unsigned int size = QDISC_ALIGN(sizeof(*sch)) + ops->priv_size; int err = -ENOBUFS; + struct net_device *dev = dev_queue->dev; - /* ensure that the Qdisc and the private data are 32-byte aligned */ - size = QDISC_ALIGN(sizeof(*sch)); - size += ops->priv_size + (QDISC_ALIGNTO - 1); + p = kzalloc_node(size, GFP_KERNEL, + netdev_queue_numa_node_read(dev_queue)); - p = kzalloc(size, GFP_KERNEL); if (!p) goto errout; sch = (struct Qdisc *) QDISC_ALIGN((unsigned long) p); - sch->padded = (char *) sch - (char *) p; - + /* if we got non aligned memory, ask more and do alignment ourself */ + if (sch != p) { + kfree(p); + p = kzalloc_node(size + QDISC_ALIGNTO - 1, GFP_KERNEL, + netdev_queue_numa_node_read(dev_queue)); + if (!p) + goto errout; + sch = (struct Qdisc *) QDISC_ALIGN((unsigned long) p); + sch->padded = (char *) sch - (char *) p; + } INIT_LIST_HEAD(&sch->list); skb_queue_head_init(&sch->q); + + spin_lock_init(&sch->busylock); + lockdep_set_class(&sch->busylock, + dev->qdisc_tx_busylock ?: &qdisc_tx_busylock); + sch->ops = ops; sch->enqueue = ops->enqueue; sch->dequeue = ops->dequeue; - sch->dev = dev; + sch->dev_queue = dev_queue; dev_hold(dev); atomic_set(&sch->refcnt, 1); return sch; errout: - return ERR_PTR(-err); + return ERR_PTR(err); } -struct Qdisc * qdisc_create_dflt(struct net_device *dev, struct Qdisc_ops *ops, - unsigned int parentid) +struct Qdisc *qdisc_create_dflt(struct netdev_queue *dev_queue, + const struct Qdisc_ops *ops, + unsigned int parentid) { struct Qdisc *sch; - sch = qdisc_alloc(dev, ops); + if (!try_module_get(ops->owner)) + goto errout; + + sch = qdisc_alloc(dev_queue, ops); if (IS_ERR(sch)) goto errout; - sch->stats_lock = &dev->queue_lock; sch->parent = parentid; if (!ops->init || ops->init(sch, NULL) == 0) @@ -490,7 +606,7 @@ errout: } EXPORT_SYMBOL(qdisc_create_dflt); -/* Under dev->queue_lock and BH! */ +/* Under qdisc_lock(qdisc) and BH! */ void qdisc_reset(struct Qdisc *qdisc) { @@ -498,20 +614,22 @@ 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_destroy(struct rcu_head *head) +static void qdisc_rcu_free(struct rcu_head *head) { - struct Qdisc *qdisc = container_of(head, struct Qdisc, q_rcu); + struct Qdisc *qdisc = container_of(head, struct Qdisc, rcu_head); + kfree((char *) qdisc - qdisc->padded); } -/* Under dev->queue_lock and BH! */ - void qdisc_destroy(struct Qdisc *qdisc) { const struct Qdisc_ops *ops = qdisc->ops; @@ -520,7 +638,11 @@ void qdisc_destroy(struct Qdisc *qdisc) !atomic_dec_and_test(&qdisc->refcnt)) return; - list_del(&qdisc->list); +#ifdef CONFIG_NET_SCHED + qdisc_list_del(qdisc); + + qdisc_put_stab(rtnl_dereference(qdisc->stab)); +#endif gen_kill_estimator(&qdisc->bstats, &qdisc->rate_est); if (ops->reset) ops->reset(qdisc); @@ -528,121 +650,299 @@ void qdisc_destroy(struct Qdisc *qdisc) ops->destroy(qdisc); module_put(ops->owner); - dev_put(qdisc->dev); - call_rcu(&qdisc->q_rcu, __qdisc_destroy); + dev_put(qdisc_dev(qdisc)); + + kfree_skb(qdisc->gso_skb); + /* + * 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); +/* Attach toplevel qdisc to device queue. */ +struct Qdisc *dev_graft_qdisc(struct netdev_queue *dev_queue, + struct Qdisc *qdisc) +{ + struct Qdisc *oqdisc = dev_queue->qdisc_sleeping; + spinlock_t *root_lock; + + root_lock = qdisc_lock(oqdisc); + spin_lock_bh(root_lock); + + /* Prune old scheduler */ + if (oqdisc && atomic_read(&oqdisc->refcnt) <= 1) + qdisc_reset(oqdisc); + + /* ... and graft new one */ + if (qdisc == NULL) + qdisc = &noop_qdisc; + dev_queue->qdisc_sleeping = qdisc; + rcu_assign_pointer(dev_queue->qdisc, &noop_qdisc); + + spin_unlock_bh(root_lock); + + return oqdisc; +} +EXPORT_SYMBOL(dev_graft_qdisc); + +static void attach_one_default_qdisc(struct net_device *dev, + struct netdev_queue *dev_queue, + void *_unused) +{ + struct Qdisc *qdisc = &noqueue_qdisc; + + if (dev->tx_queue_len) { + qdisc = qdisc_create_dflt(dev_queue, + default_qdisc_ops, TC_H_ROOT); + if (!qdisc) { + netdev_info(dev, "activation failed\n"); + return; + } + if (!netif_is_multiqueue(dev)) + qdisc->flags |= TCQ_F_ONETXQUEUE; + } + 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(txq, &mq_qdisc_ops, TC_H_ROOT); + if (qdisc) { + dev->qdisc = qdisc; + qdisc->ops->attach(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; + + 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) { + dev_queue->trans_start = 0; + *need_watchdog_p = 1; + } +} + void dev_activate(struct net_device *dev) { + int need_watchdog; + /* No queueing discipline is attached to device; - create default one i.e. pfifo_fast for devices, - which need queueing and noqueue_qdisc for - virtual interfaces + * create default one for devices, which need queueing + * and noqueue_qdisc for virtual interfaces */ - if (dev->qdisc_sleeping == &noop_qdisc) { - struct Qdisc *qdisc; - if (dev->tx_queue_len) { - qdisc = qdisc_create_dflt(dev, &pfifo_fast_ops, - TC_H_ROOT); - if (qdisc == NULL) { - printk(KERN_INFO "%s: activation failed\n", dev->name); - return; - } - list_add_tail(&qdisc->list, &dev->qdisc_list); - } else { - qdisc = &noqueue_qdisc; - } - dev->qdisc_sleeping = qdisc; - } + if (dev->qdisc == &noop_qdisc) + attach_default_qdiscs(dev); if (!netif_carrier_ok(dev)) /* Delay activation until next carrier-on event */ return; - spin_lock_bh(&dev->queue_lock); - rcu_assign_pointer(dev->qdisc, dev->qdisc_sleeping); - if (dev->qdisc != &noqueue_qdisc) { + need_watchdog = 0; + netdev_for_each_tx_queue(dev, transition_one_qdisc, &need_watchdog); + if (dev_ingress_queue(dev)) + transition_one_qdisc(dev, dev_ingress_queue(dev), NULL); + + if (need_watchdog) { dev->trans_start = jiffies; dev_watchdog_up(dev); } - spin_unlock_bh(&dev->queue_lock); } +EXPORT_SYMBOL(dev_activate); -void dev_deactivate(struct net_device *dev) +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; - int running; - spin_lock_bh(&dev->queue_lock); - qdisc = dev->qdisc; - dev->qdisc = &noop_qdisc; + qdisc = dev_queue->qdisc; + if (qdisc) { + spin_lock_bh(qdisc_lock(qdisc)); - qdisc_reset(qdisc); + if (!(qdisc->flags & TCQ_F_BUILTIN)) + set_bit(__QDISC_STATE_DEACTIVATED, &qdisc->state); - skb = dev->gso_skb; - dev->gso_skb = NULL; - spin_unlock_bh(&dev->queue_lock); + rcu_assign_pointer(dev_queue->qdisc, qdisc_default); + qdisc_reset(qdisc); - kfree_skb(skb); + spin_unlock_bh(qdisc_lock(qdisc)); + } +} + +static bool some_qdisc_is_busy(struct net_device *dev) +{ + unsigned int i; + + for (i = 0; i < dev->num_tx_queues; i++) { + struct netdev_queue *dev_queue; + spinlock_t *root_lock; + struct Qdisc *q; + int val; - dev_watchdog_down(dev); + dev_queue = netdev_get_tx_queue(dev, i); + q = dev_queue->qdisc_sleeping; + root_lock = qdisc_lock(q); - /* Wait for outstanding qdisc-less dev_queue_xmit calls. */ - synchronize_rcu(); + spin_lock_bh(root_lock); + + val = (qdisc_is_running(q) || + test_bit(__QDISC_STATE_SCHED, &q->state)); + + spin_unlock_bh(root_lock); + + if (val) + return true; + } + return false; +} + +/** + * dev_deactivate_many - deactivate transmissions on several devices + * @head: list of devices to deactivate + * + * This function returns only when all outstanding transmissions + * have completed, unless all devices are in dismantle phase. + */ +void dev_deactivate_many(struct list_head *head) +{ + struct net_device *dev; + bool sync_needed = false; + + list_for_each_entry(dev, head, close_list) { + netdev_for_each_tx_queue(dev, dev_deactivate_queue, + &noop_qdisc); + if (dev_ingress_queue(dev)) + dev_deactivate_queue(dev, dev_ingress_queue(dev), + &noop_qdisc); + + dev_watchdog_down(dev); + sync_needed |= !dev->dismantle; + } + + /* Wait for outstanding qdisc-less dev_queue_xmit calls. + * This is avoided if all devices are in dismantle phase : + * Caller will call synchronize_net() for us + */ + if (sync_needed) + synchronize_net(); /* Wait for outstanding qdisc_run calls. */ - do { - while (test_bit(__LINK_STATE_QDISC_RUNNING, &dev->state)) + list_for_each_entry(dev, head, close_list) + while (some_qdisc_is_busy(dev)) yield(); +} - /* - * Double-check inside queue lock to ensure that all effects - * of the queue run are visible when we return. - */ - spin_lock_bh(&dev->queue_lock); - running = test_bit(__LINK_STATE_QDISC_RUNNING, &dev->state); - spin_unlock_bh(&dev->queue_lock); +void dev_deactivate(struct net_device *dev) +{ + LIST_HEAD(single); - /* - * 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)); + list_add(&dev->close_list, &single); + dev_deactivate_many(&single); + list_del(&single); +} +EXPORT_SYMBOL(dev_deactivate); + +static void dev_init_scheduler_queue(struct net_device *dev, + struct netdev_queue *dev_queue, + void *_qdisc) +{ + struct Qdisc *qdisc = _qdisc; + + dev_queue->qdisc = qdisc; + dev_queue->qdisc_sleeping = qdisc; } void dev_init_scheduler(struct net_device *dev) { - qdisc_lock_tree(dev); dev->qdisc = &noop_qdisc; - dev->qdisc_sleeping = &noop_qdisc; - INIT_LIST_HEAD(&dev->qdisc_list); - qdisc_unlock_tree(dev); + netdev_for_each_tx_queue(dev, dev_init_scheduler_queue, &noop_qdisc); + if (dev_ingress_queue(dev)) + dev_init_scheduler_queue(dev, dev_ingress_queue(dev), &noop_qdisc); setup_timer(&dev->watchdog_timer, dev_watchdog, (unsigned long)dev); } -void dev_shutdown(struct net_device *dev) +static void shutdown_scheduler_queue(struct net_device *dev, + struct netdev_queue *dev_queue, + void *_qdisc_default) { - struct Qdisc *qdisc; + struct Qdisc *qdisc = dev_queue->qdisc_sleeping; + struct Qdisc *qdisc_default = _qdisc_default; + + if (qdisc) { + rcu_assign_pointer(dev_queue->qdisc, qdisc_default); + dev_queue->qdisc_sleeping = qdisc_default; - qdisc_lock_tree(dev); - qdisc = dev->qdisc_sleeping; - dev->qdisc = &noop_qdisc; - dev->qdisc_sleeping = &noop_qdisc; - qdisc_destroy(qdisc); -#if defined(CONFIG_NET_SCH_INGRESS) || defined(CONFIG_NET_SCH_INGRESS_MODULE) - if ((qdisc = dev->qdisc_ingress) != NULL) { - dev->qdisc_ingress = NULL; qdisc_destroy(qdisc); } -#endif - BUG_TRAP(!timer_pending(&dev->watchdog_timer)); - qdisc_unlock_tree(dev); } + +void dev_shutdown(struct net_device *dev) +{ + netdev_for_each_tx_queue(dev, shutdown_scheduler_queue, &noop_qdisc); + if (dev_ingress_queue(dev)) + shutdown_scheduler_queue(dev, dev_ingress_queue(dev), &noop_qdisc); + qdisc_destroy(dev->qdisc); + dev->qdisc = &noop_qdisc; + + WARN_ON(timer_pending(&dev->watchdog_timer)); +} + +void psched_ratecfg_precompute(struct psched_ratecfg *r, + const struct tc_ratespec *conf, + u64 rate64) +{ + memset(r, 0, sizeof(*r)); + r->overhead = conf->overhead; + r->rate_bytes_ps = max_t(u64, conf->rate, rate64); + r->linklayer = (conf->linklayer & TC_LINKLAYER_MASK); + r->mult = 1; + /* + * The deal here is to replace a divide by a reciprocal one + * in fast path (a reciprocal divide is a multiply and a shift) + * + * Normal formula would be : + * time_in_ns = (NSEC_PER_SEC * len) / rate_bps + * + * We compute mult/shift to use instead : + * time_in_ns = (len * mult) >> shift; + * + * We try to get the highest possible mult value for accuracy, + * but have to make sure no overflows will ever happen. + */ + if (r->rate_bytes_ps > 0) { + u64 factor = NSEC_PER_SEC; + + for (;;) { + r->mult = div64_u64(factor, r->rate_bytes_ps); + if (r->mult & (1U << 31) || factor & (1ULL << 63)) + break; + factor <<= 1; + r->shift++; + } + } +} +EXPORT_SYMBOL(psched_ratecfg_precompute); |
