Merge git://oss.sgi.com:8090/xfs/xfs-2.6
[linux-drm-fsl-dcu.git] / net / sched / sch_generic.c
index 0834c2ee917408286d3cf366645c6bd6b3e8fc43..52eb3439d7c6bf561dc88fca37fdaea0e8a1da4b 100644 (file)
@@ -36,7 +36,7 @@
 
 /* Main transmission queue. */
 
-/* Main qdisc structure lock. 
+/* Main qdisc structure lock.
 
    However, modifications
    to data, participating in scheduling must be additionally
    The idea is the following:
    - enqueue, dequeue are serialized via top level device
      spinlock dev->queue_lock.
-   - tree walking is protected by read_lock_bh(qdisc_tree_lock)
+   - tree walking is protected by read_lock(qdisc_tree_lock)
      and this lock is used only in process context.
-   - updates to tree are made under rtnl semaphore or
-     from softirq context (__qdisc_destroy rcu-callback)
-     hence this lock needs local bh disabling.
+   - updates to tree are made only under rtnl semaphore,
+     hence this lock may be made without local bh disabling.
 
    qdisc_tree_lock must be grabbed BEFORE dev->queue_lock!
  */
@@ -57,17 +56,17 @@ DEFINE_RWLOCK(qdisc_tree_lock);
 
 void qdisc_lock_tree(struct net_device *dev)
 {
-       write_lock_bh(&qdisc_tree_lock);
+       write_lock(&qdisc_tree_lock);
        spin_lock_bh(&dev->queue_lock);
 }
 
 void qdisc_unlock_tree(struct net_device *dev)
 {
        spin_unlock_bh(&dev->queue_lock);
-       write_unlock_bh(&qdisc_tree_lock);
+       write_unlock(&qdisc_tree_lock);
 }
 
-/* 
+/*
    dev->queue_lock serializes queue accesses for this device
    AND dev->qdisc pointer itself.
 
@@ -83,7 +82,7 @@ void qdisc_unlock_tree(struct net_device *dev)
    we do not check dev->tbusy flag here.
 
    Returns:  0  - queue is empty.
-            >0  - queue is not empty, but throttled.
+           >0  - queue is not empty, but throttled.
            <0  - queue is not empty. Device is throttled, if dev->tbusy != 0.
 
    NOTE: Called under dev->queue_lock with locally disabled BH.
@@ -113,7 +112,7 @@ static inline int qdisc_restart(struct net_device *dev)
                        if (!netif_tx_trylock(dev)) {
                        collision:
                                /* So, someone grabbed the driver. */
-                               
+
                                /* It may be transient configuration error,
                                   when hard_start_xmit() recurses. We detect
                                   it by checking xmit owner and drop the
@@ -129,7 +128,7 @@ static inline int qdisc_restart(struct net_device *dev)
                                goto requeue;
                        }
                }
-               
+
                {
                        /* And release queue */
                        spin_unlock(&dev->queue_lock);
@@ -138,7 +137,7 @@ static inline int qdisc_restart(struct net_device *dev)
                                int ret;
 
                                ret = dev_hard_start_xmit(skb, dev);
-                               if (ret == NETDEV_TX_OK) { 
+                               if (ret == NETDEV_TX_OK) {
                                        if (!nolock) {
                                                netif_tx_unlock(dev);
                                        }
@@ -147,15 +146,15 @@ static inline int qdisc_restart(struct net_device *dev)
                                }
                                if (ret == NETDEV_TX_LOCKED && nolock) {
                                        spin_lock(&dev->queue_lock);
-                                       goto collision; 
+                                       goto collision;
                                }
                        }
 
                        /* NETDEV_TX_BUSY - we need to requeue */
                        /* Release the driver */
-                       if (!nolock) { 
+                       if (!nolock) {
                                netif_tx_unlock(dev);
-                       } 
+                       }
                        spin_lock(&dev->queue_lock);
                        q = dev->qdisc;
                }
@@ -210,7 +209,7 @@ static void dev_watchdog(unsigned long arg)
                                       dev->name);
                                dev->tx_timeout(dev);
                        }
-                       if (!mod_timer(&dev->watchdog_timer, jiffies + dev->watchdog_timeo))
+                       if (!mod_timer(&dev->watchdog_timer, round_jiffies(jiffies + dev->watchdog_timeo)))
                                dev_hold(dev);
                }
        }
@@ -238,9 +237,7 @@ void __netdev_watchdog_up(struct net_device *dev)
 
 static void dev_watchdog_up(struct net_device *dev)
 {
-       netif_tx_lock_bh(dev);
        __netdev_watchdog_up(dev);
-       netif_tx_unlock_bh(dev);
 }
 
 static void dev_watchdog_down(struct net_device *dev)
@@ -303,7 +300,7 @@ struct Qdisc noop_qdisc = {
        .enqueue        =       noop_enqueue,
        .dequeue        =       noop_dequeue,
        .flags          =       TCQ_F_BUILTIN,
-       .ops            =       &noop_qdisc_ops,        
+       .ops            =       &noop_qdisc_ops,
        .list           =       LIST_HEAD_INIT(noop_qdisc.list),
 };
 
@@ -453,13 +450,15 @@ errout:
        return ERR_PTR(-err);
 }
 
-struct Qdisc * qdisc_create_dflt(struct net_device *dev, struct Qdisc_ops *ops)
+struct Qdisc * qdisc_create_dflt(struct net_device *dev, struct Qdisc_ops *ops,
+                                unsigned int parentid)
 {
        struct Qdisc *sch;
-       
+
        sch = qdisc_alloc(dev, ops);
        if (IS_ERR(sch))
                goto errout;
+       sch->parent = parentid;
 
        if (!ops->init || ops->init(sch, NULL) == 0)
                return sch;
@@ -479,26 +478,12 @@ void qdisc_reset(struct Qdisc *qdisc)
                ops->reset(qdisc);
 }
 
-/* this is the rcu callback function to clean up a qdisc when there 
+/* 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)
 {
        struct Qdisc *qdisc = container_of(head, struct Qdisc, q_rcu);
-       struct Qdisc_ops  *ops = qdisc->ops;
-
-#ifdef CONFIG_NET_ESTIMATOR
-       gen_kill_estimator(&qdisc->bstats, &qdisc->rate_est);
-#endif
-       write_lock(&qdisc_tree_lock);
-       if (ops->reset)
-               ops->reset(qdisc);
-       if (ops->destroy)
-               ops->destroy(qdisc);
-       write_unlock(&qdisc_tree_lock);
-       module_put(ops->owner);
-
-       dev_put(qdisc->dev);
        kfree((char *) qdisc - qdisc->padded);
 }
 
@@ -506,32 +491,23 @@ static void __qdisc_destroy(struct rcu_head *head)
 
 void qdisc_destroy(struct Qdisc *qdisc)
 {
-       struct list_head cql = LIST_HEAD_INIT(cql);
-       struct Qdisc *cq, *q, *n;
+       struct Qdisc_ops  *ops = qdisc->ops;
 
        if (qdisc->flags & TCQ_F_BUILTIN ||
-               !atomic_dec_and_test(&qdisc->refcnt))
+           !atomic_dec_and_test(&qdisc->refcnt))
                return;
 
-       if (!list_empty(&qdisc->list)) {
-               if (qdisc->ops->cl_ops == NULL)
-                       list_del(&qdisc->list);
-               else
-                       list_move(&qdisc->list, &cql);
-       }
-
-       /* unlink inner qdiscs from dev->qdisc_list immediately */
-       list_for_each_entry(cq, &cql, list)
-               list_for_each_entry_safe(q, n, &qdisc->dev->qdisc_list, list)
-                       if (TC_H_MAJ(q->parent) == TC_H_MAJ(cq->handle)) {
-                               if (q->ops->cl_ops == NULL)
-                                       list_del_init(&q->list);
-                               else
-                                       list_move_tail(&q->list, &cql);
-                       }
-       list_for_each_entry_safe(cq, n, &cql, list)
-               list_del_init(&cq->list);
+       list_del(&qdisc->list);
+#ifdef CONFIG_NET_ESTIMATOR
+       gen_kill_estimator(&qdisc->bstats, &qdisc->rate_est);
+#endif
+       if (ops->reset)
+               ops->reset(qdisc);
+       if (ops->destroy)
+               ops->destroy(qdisc);
 
+       module_put(ops->owner);
+       dev_put(qdisc->dev);
        call_rcu(&qdisc->q_rcu, __qdisc_destroy);
 }
 
@@ -546,20 +522,21 @@ void dev_activate(struct net_device *dev)
        if (dev->qdisc_sleeping == &noop_qdisc) {
                struct Qdisc *qdisc;
                if (dev->tx_queue_len) {
-                       qdisc = qdisc_create_dflt(dev, &pfifo_fast_ops);
+                       qdisc = qdisc_create_dflt(dev, &pfifo_fast_ops,
+                                                 TC_H_ROOT);
                        if (qdisc == NULL) {
                                printk(KERN_INFO "%s: activation failed\n", dev->name);
                                return;
                        }
-                       write_lock_bh(&qdisc_tree_lock);
+                       write_lock(&qdisc_tree_lock);
                        list_add_tail(&qdisc->list, &dev->qdisc_list);
-                       write_unlock_bh(&qdisc_tree_lock);
+                       write_unlock(&qdisc_tree_lock);
                } else {
                        qdisc =  &noqueue_qdisc;
                }
-               write_lock_bh(&qdisc_tree_lock);
+               write_lock(&qdisc_tree_lock);
                dev->qdisc_sleeping = qdisc;
-               write_unlock_bh(&qdisc_tree_lock);
+               write_unlock(&qdisc_tree_lock);
        }
 
        if (!netif_carrier_ok(dev))
@@ -623,22 +600,19 @@ void dev_shutdown(struct net_device *dev)
        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) {
+       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);
 }
 
-EXPORT_SYMBOL(__netdev_watchdog_up);
 EXPORT_SYMBOL(netif_carrier_on);
 EXPORT_SYMBOL(netif_carrier_off);
 EXPORT_SYMBOL(noop_qdisc);
-EXPORT_SYMBOL(noop_qdisc_ops);
 EXPORT_SYMBOL(qdisc_create_dflt);
-EXPORT_SYMBOL(qdisc_alloc);
 EXPORT_SYMBOL(qdisc_destroy);
 EXPORT_SYMBOL(qdisc_reset);
 EXPORT_SYMBOL(qdisc_lock_tree);