commit 6ab8d4a8e3df7976fc2db1e1181216a213df89d5 Author: Patrick McHardy Date: Fri Sep 4 03:07:39 2009 +0200 net_sched: reintroduce dev->qdisc for use by sch_api Currently the multiqueue integration with the qdisc API suffers from a few problems: - with multiple queues, all root qdiscs use the same handle. This means they can't be exposed to userspace in a backwards compatible fashion. - all API operations always refer to queue number 0. Newly created qdiscs are automatically shared between all queues, its not possible to address individual queues or restore multiqueue behaviour once a shared qdisc has been attached. - Dumps only contain the root qdisc of queue 0, in case of non-shared qdiscs this means the statistics are incomplete. This patch reintroduces dev->qdisc, which points to the (single) root qdisc from userspace's point of view. Currently it either points to the first (non-shared) default qdisc, or a qdisc shared between all queues. The following patches will introduce a classful dummy qdisc, which will be used as root qdisc and contain the per-queue qdiscs as children. Signed-off-by: Patrick McHardy diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index 121cbad..a44118b 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -832,6 +832,9 @@ struct net_device /* Number of TX queues currently active in device */ unsigned int real_num_tx_queues; + /* root qdisc from userspace point of view */ + struct Qdisc *qdisc; + unsigned long tx_queue_len; /* Max frames per queue allowed */ spinlock_t tx_global_lock; /* diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c index 5c1fe53..1aebdc1 100644 --- a/net/core/rtnetlink.c +++ b/net/core/rtnetlink.c @@ -606,7 +606,6 @@ static int rtnl_fill_ifinfo(struct sk_buff *skb, struct net_device *dev, int type, u32 pid, u32 seq, u32 change, unsigned int flags) { - struct netdev_queue *txq; struct ifinfomsg *ifm; struct nlmsghdr *nlh; const struct net_device_stats *stats; @@ -637,9 +636,8 @@ static int rtnl_fill_ifinfo(struct sk_buff *skb, struct net_device *dev, if (dev->master) NLA_PUT_U32(skb, IFLA_MASTER, dev->master->ifindex); - txq = netdev_get_tx_queue(dev, 0); - if (txq->qdisc_sleeping) - NLA_PUT_STRING(skb, IFLA_QDISC, txq->qdisc_sleeping->ops->id); + if (dev->qdisc) + NLA_PUT_STRING(skb, IFLA_QDISC, dev->qdisc->ops->id); if (dev->ifalias) NLA_PUT_STRING(skb, IFLA_IFALIAS, dev->ifalias); diff --git a/net/sched/cls_api.c b/net/sched/cls_api.c index 09cdcdf..e857441 100644 --- a/net/sched/cls_api.c +++ b/net/sched/cls_api.c @@ -168,8 +168,7 @@ replay: /* Find qdisc */ if (!parent) { - struct netdev_queue *dev_queue = netdev_get_tx_queue(dev, 0); - q = dev_queue->qdisc_sleeping; + q = dev->qdisc; parent = q->handle; } else { q = qdisc_lookup(dev, TC_H_MAJ(t->tcm_parent)); @@ -405,7 +404,6 @@ static int tcf_node_dump(struct tcf_proto *tp, unsigned long n, static int tc_dump_tfilter(struct sk_buff *skb, struct netlink_callback *cb) { struct net *net = sock_net(skb->sk); - struct netdev_queue *dev_queue; int t; int s_t; struct net_device *dev; @@ -424,9 +422,8 @@ static int tc_dump_tfilter(struct sk_buff *skb, struct netlink_callback *cb) if ((dev = dev_get_by_index(&init_net, tcm->tcm_ifindex)) == NULL) return skb->len; - dev_queue = netdev_get_tx_queue(dev, 0); if (!tcm->tcm_parent) - q = dev_queue->qdisc_sleeping; + q = dev->qdisc; else q = qdisc_lookup(dev, TC_H_MAJ(tcm->tcm_parent)); if (!q) diff --git a/net/sched/sch_api.c b/net/sched/sch_api.c index 24d17ce..285ca25 100644 --- a/net/sched/sch_api.c +++ b/net/sched/sch_api.c @@ -207,7 +207,7 @@ static struct Qdisc *qdisc_match_from_root(struct Qdisc *root, u32 handle) static void qdisc_list_add(struct Qdisc *q) { if ((q->parent != TC_H_ROOT) && !(q->flags & TCQ_F_INGRESS)) - list_add_tail(&q->list, &qdisc_root_sleeping(q)->list); + list_add_tail(&q->list, &qdisc_dev(q)->qdisc->list); } void qdisc_list_del(struct Qdisc *q) @@ -219,17 +219,11 @@ EXPORT_SYMBOL(qdisc_list_del); struct Qdisc *qdisc_lookup(struct net_device *dev, u32 handle) { - unsigned int i; struct Qdisc *q; - for (i = 0; i < dev->num_tx_queues; i++) { - struct netdev_queue *txq = netdev_get_tx_queue(dev, i); - struct Qdisc *txq_root = txq->qdisc_sleeping; - - q = qdisc_match_from_root(txq_root, handle); - if (q) - goto out; - } + q = qdisc_match_from_root(dev->qdisc, handle); + if (q) + goto out; q = qdisc_match_from_root(dev->rx_queue.qdisc_sleeping, handle); out: @@ -720,9 +714,14 @@ static int qdisc_graft(struct net_device *dev, struct Qdisc *parent, if (new && i > 0) atomic_inc(&new->refcnt); - notify_and_destroy(skb, n, classid, old, new); + qdisc_destroy(old); } + notify_and_destroy(skb, n, classid, dev->qdisc, new); + if (new) + atomic_inc(&new->refcnt); + dev->qdisc = new ? : &noop_qdisc; + if (dev->flags & IFF_UP) dev_activate(dev); } else { @@ -974,9 +973,7 @@ static int tc_get_qdisc(struct sk_buff *skb, struct nlmsghdr *n, void *arg) q = dev->rx_queue.qdisc_sleeping; } } else { - struct netdev_queue *dev_queue; - dev_queue = netdev_get_tx_queue(dev, 0); - q = dev_queue->qdisc_sleeping; + q = dev->qdisc; } if (!q) return -ENOENT; @@ -1044,9 +1041,7 @@ replay: q = dev->rx_queue.qdisc_sleeping; } } else { - struct netdev_queue *dev_queue; - dev_queue = netdev_get_tx_queue(dev, 0); - q = dev_queue->qdisc_sleeping; + q = dev->qdisc; } /* It may be default qdisc, ignore it */ @@ -1291,8 +1286,7 @@ static int tc_dump_qdisc(struct sk_buff *skb, struct netlink_callback *cb) s_q_idx = 0; q_idx = 0; - dev_queue = netdev_get_tx_queue(dev, 0); - if (tc_dump_qdisc_root(dev_queue->qdisc_sleeping, skb, cb, &q_idx, s_q_idx) < 0) + if (tc_dump_qdisc_root(dev->qdisc, skb, cb, &q_idx, s_q_idx) < 0) goto done; dev_queue = &dev->rx_queue; @@ -1323,7 +1317,6 @@ done: static int tc_ctl_tclass(struct sk_buff *skb, struct nlmsghdr *n, void *arg) { struct net *net = sock_net(skb->sk); - struct netdev_queue *dev_queue; struct tcmsg *tcm = NLMSG_DATA(n); struct nlattr *tca[TCA_MAX + 1]; struct net_device *dev; @@ -1361,7 +1354,6 @@ static int tc_ctl_tclass(struct sk_buff *skb, struct nlmsghdr *n, void *arg) /* Step 1. Determine qdisc handle X:0 */ - dev_queue = netdev_get_tx_queue(dev, 0); if (pid != TC_H_ROOT) { u32 qid1 = TC_H_MAJ(pid); @@ -1372,7 +1364,7 @@ static int tc_ctl_tclass(struct sk_buff *skb, struct nlmsghdr *n, void *arg) } else if (qid1) { qid = qid1; } else if (qid == 0) - qid = dev_queue->qdisc_sleeping->handle; + qid = dev->qdisc->handle; /* Now qid is genuine qdisc handle consistent both with parent and child. @@ -1383,7 +1375,7 @@ static int tc_ctl_tclass(struct sk_buff *skb, struct nlmsghdr *n, void *arg) pid = TC_H_MAKE(qid, pid); } else { if (qid == 0) - qid = dev_queue->qdisc_sleeping->handle; + qid = dev->qdisc->handle; } /* OK. Locate qdisc */ @@ -1584,8 +1576,7 @@ static int tc_dump_tclass(struct sk_buff *skb, struct netlink_callback *cb) s_t = cb->args[0]; t = 0; - dev_queue = netdev_get_tx_queue(dev, 0); - if (tc_dump_tclass_root(dev_queue->qdisc_sleeping, skb, tcm, cb, &t, s_t) < 0) + if (tc_dump_tclass_root(dev->qdisc, skb, tcm, cb, &t, s_t) < 0) goto done; dev_queue = &dev->rx_queue; diff --git a/net/sched/sch_generic.c b/net/sched/sch_generic.c index 6128e6f..a91f079 100644 --- a/net/sched/sch_generic.c +++ b/net/sched/sch_generic.c @@ -623,19 +623,6 @@ void qdisc_destroy(struct Qdisc *qdisc) } 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) @@ -677,6 +664,7 @@ static void transition_one_qdisc(struct net_device *dev, void dev_activate(struct net_device *dev) { + struct netdev_queue *txq; int need_watchdog; /* No queueing discipline is attached to device; @@ -685,9 +673,14 @@ void dev_activate(struct net_device *dev) virtual interfaces */ - if (dev_all_qdisc_sleeping_noop(dev)) + if (dev->qdisc == &noop_qdisc) { netdev_for_each_tx_queue(dev, attach_one_default_qdisc, NULL); + txq = netdev_get_tx_queue(dev, 0); + dev->qdisc = txq->qdisc_sleeping; + atomic_inc(&dev->qdisc->refcnt); + } + if (!netif_carrier_ok(dev)) /* Delay activation until next carrier-on event */ return; @@ -777,6 +770,7 @@ 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); @@ -802,5 +796,8 @@ 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)); }