From f84bb1eac0275283ccd76455e20f926e186ea8c8 Mon Sep 17 00:00:00 2001 From: Phil Sutter Date: Thu, 27 Aug 2015 21:21:36 +0200 Subject: net: fix IFF_NO_QUEUE for drivers using alloc_netdev Printing a warning in alloc_netdev_mqs() if tx_queue_len is zero and IFF_NO_QUEUE not set is not appropriate since drivers may use one of the alloc_netdev* macros instead of alloc_etherdev*, thereby not intentionally leaving tx_queue_len uninitialized. Instead check here if tx_queue_len is zero and set IFF_NO_QUEUE, so the value of tx_queue_len can be ignored in net/sched_generic.c. Fixes: 906470c ("net: warn if drivers set tx_queue_len = 0") Signed-off-by: Phil Sutter Signed-off-by: David S. Miller --- net/core/dev.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/core/dev.c b/net/core/dev.c index a8e6cf4298d3..877c84834d81 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -7010,7 +7010,7 @@ struct net_device *alloc_netdev_mqs(int sizeof_priv, const char *name, setup(dev); if (!dev->tx_queue_len) - printk(KERN_WARNING "%s uses DEPRECATED zero tx_queue_len - convert driver to use IFF_NO_QUEUE instead.\n", name); + dev->priv_flags |= IFF_NO_QUEUE; dev->num_tx_queues = txqs; dev->real_num_tx_queues = txqs; -- cgit v1.2.3-59-g8ed1b From db4094bca7a5746bc8e36db0557e8732963e88f0 Mon Sep 17 00:00:00 2001 From: Phil Sutter Date: Thu, 27 Aug 2015 21:21:37 +0200 Subject: net: sched: ignore tx_queue_len when assigning default qdisc Since alloc_netdev_mqs() sets IFF_NO_QUEUE for drivers not initializing tx_queue_len, it is safe to assume that if tx_queue_len is zero, dev->priv flags always contains IFF_NO_QUEUE. Signed-off-by: Phil Sutter Signed-off-by: David S. Miller --- net/sched/sch_generic.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/net/sched/sch_generic.c b/net/sched/sch_generic.c index 942fea8405a4..f501b7409320 100644 --- a/net/sched/sch_generic.c +++ b/net/sched/sch_generic.c @@ -735,7 +735,7 @@ static void attach_one_default_qdisc(struct net_device *dev, { struct Qdisc *qdisc = &noqueue_qdisc; - if (dev->tx_queue_len && !(dev->priv_flags & IFF_NO_QUEUE)) { + if (!(dev->priv_flags & IFF_NO_QUEUE)) { qdisc = qdisc_create_dflt(dev_queue, default_qdisc_ops, TC_H_ROOT); if (!qdisc) { @@ -756,7 +756,6 @@ static void attach_default_qdiscs(struct net_device *dev) txq = netdev_get_tx_queue(dev, 0); if (!netif_is_multiqueue(dev) || - dev->tx_queue_len == 0 || dev->priv_flags & IFF_NO_QUEUE) { netdev_for_each_tx_queue(dev, attach_one_default_qdisc, NULL); dev->qdisc = txq->qdisc_sleeping; -- cgit v1.2.3-59-g8ed1b From d66d6c3152e8d5a6db42a56bf7ae1c6cae87ba48 Mon Sep 17 00:00:00 2001 From: Phil Sutter Date: Thu, 27 Aug 2015 21:21:38 +0200 Subject: net: sched: register noqueue qdisc This way users can attach noqueue just like any other qdisc using tc without having to mess with tx_queue_len first. Signed-off-by: Phil Sutter Signed-off-by: David S. Miller --- include/net/sch_generic.h | 1 + net/sched/sch_api.c | 1 + net/sched/sch_generic.c | 12 +++++++++++- 3 files changed, 13 insertions(+), 1 deletion(-) diff --git a/include/net/sch_generic.h b/include/net/sch_generic.h index 2eab08c38e32..444faa89a55f 100644 --- a/include/net/sch_generic.h +++ b/include/net/sch_generic.h @@ -340,6 +340,7 @@ extern struct Qdisc noop_qdisc; extern struct Qdisc_ops noop_qdisc_ops; extern struct Qdisc_ops pfifo_fast_ops; extern struct Qdisc_ops mq_qdisc_ops; +extern struct Qdisc_ops noqueue_qdisc_ops; extern const struct Qdisc_ops *default_qdisc_ops; struct Qdisc_class_common { diff --git a/net/sched/sch_api.c b/net/sched/sch_api.c index 59c227f26b56..a3c70a18a764 100644 --- a/net/sched/sch_api.c +++ b/net/sched/sch_api.c @@ -1942,6 +1942,7 @@ static int __init pktsched_init(void) register_qdisc(&bfifo_qdisc_ops); register_qdisc(&pfifo_head_drop_qdisc_ops); register_qdisc(&mq_qdisc_ops); + register_qdisc(&noqueue_qdisc_ops); rtnl_register(PF_UNSPEC, RTM_NEWQDISC, tc_modify_qdisc, NULL, NULL); rtnl_register(PF_UNSPEC, RTM_DELQDISC, tc_get_qdisc, NULL, NULL); diff --git a/net/sched/sch_generic.c b/net/sched/sch_generic.c index f501b7409320..d5c7c0d88786 100644 --- a/net/sched/sch_generic.c +++ b/net/sched/sch_generic.c @@ -416,9 +416,19 @@ struct Qdisc noop_qdisc = { }; EXPORT_SYMBOL(noop_qdisc); -static struct Qdisc_ops noqueue_qdisc_ops __read_mostly = { +static int noqueue_init(struct Qdisc *qdisc, struct nlattr *opt) +{ + /* register_qdisc() assigns a default of noop_enqueue if unset, + * but __dev_queue_xmit() treats noqueue only as such + * if this is NULL - so clear it here. */ + qdisc->enqueue = NULL; + return 0; +} + +struct Qdisc_ops noqueue_qdisc_ops __read_mostly = { .id = "noqueue", .priv_size = 0, + .init = noqueue_init, .enqueue = noop_enqueue, .dequeue = noop_dequeue, .peek = noop_dequeue, -- cgit v1.2.3-59-g8ed1b From 3e692f21532a54eeb5e6fc0ccc214cfa56fe23d3 Mon Sep 17 00:00:00 2001 From: Phil Sutter Date: Thu, 27 Aug 2015 21:21:39 +0200 Subject: net: sched: simplify attach_one_default_qdisc() Now that noqueue qdisc can be attached just like any other qdisc, no special treatment is necessary anymore when attaching it as default qdisc. This change has the added benefit that 'tc qdisc show' prints noqueue instead of nothing for devices defaulting to noqueue. Signed-off-by: Phil Sutter Signed-off-by: David S. Miller --- net/sched/sch_generic.c | 41 ++++++++++++----------------------------- 1 file changed, 12 insertions(+), 29 deletions(-) diff --git a/net/sched/sch_generic.c b/net/sched/sch_generic.c index d5c7c0d88786..cb5d4ad32946 100644 --- a/net/sched/sch_generic.c +++ b/net/sched/sch_generic.c @@ -435,24 +435,6 @@ struct Qdisc_ops noqueue_qdisc_ops __read_mostly = { .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 }; @@ -743,18 +725,19 @@ static void attach_one_default_qdisc(struct net_device *dev, struct netdev_queue *dev_queue, void *_unused) { - struct Qdisc *qdisc = &noqueue_qdisc; + struct Qdisc *qdisc; + const struct Qdisc_ops *ops = default_qdisc_ops; - if (!(dev->priv_flags & IFF_NO_QUEUE)) { - 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; + if (dev->priv_flags & IFF_NO_QUEUE) + ops = &noqueue_qdisc_ops; + + qdisc = qdisc_create_dflt(dev_queue, 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; } @@ -790,7 +773,7 @@ static void transition_one_qdisc(struct net_device *dev, 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) { dev_queue->trans_start = 0; *need_watchdog_p = 1; } -- cgit v1.2.3-59-g8ed1b