From 41a23b0788610b27ecb4c4ee857f3fe7168f1070 Mon Sep 17 00:00:00 2001 From: Herbert Xu Date: Thu, 10 May 2007 14:12:47 -0700 Subject: [PATCH] [NET_SCHED]: Avoid requeue warning on dev_deactivate When we relinquish queue_lock in qdisc_restart and then retake it for requeueing, we might race against dev_deactivate and end up requeueing onto noop_qdisc. This causes a warning to be printed. This patch fixes this by checking this before we requeue. As an added bonus, we can remove the same check in __qdisc_run which was added to prevent dev->gso_skb from being requeued when we're shutting down. Even though we've had to add a new conditional in its place, it's better because it only happens on requeues rather than every single time that qdisc_run is called. For this to work we also need to move the clearing of gso_skb up in dev_deactivate as now qdisc_restart can occur even after we wait for __LINK_STATE_QDISC_RUNNING to clear (but it won't do anything as long as the queue and gso_skb is already clear). Signed-off-by: Herbert Xu Signed-off-by: David S. Miller --- net/sched/sch_generic.c | 18 ++++++++---------- 1 file changed, 8 insertions(+), 10 deletions(-) diff --git a/net/sched/sch_generic.c b/net/sched/sch_generic.c index 816d311..f28bb2d 100644 --- a/net/sched/sch_generic.c +++ b/net/sched/sch_generic.c @@ -162,7 +162,9 @@ static inline int qdisc_restart(struct net_device *dev) */ requeue: - if (skb->next) + if (unlikely(q == &noop_qdisc)) + kfree_skb(skb); + else if (skb->next) dev->gso_skb = skb; else q->ops->requeue(skb, q); @@ -177,15 +179,11 @@ out: void __qdisc_run(struct net_device *dev) { - if (unlikely(dev->qdisc == &noop_qdisc)) - goto out; - do { if (!qdisc_restart(dev)) break; } while (!netif_queue_stopped(dev)); -out: clear_bit(__LINK_STATE_QDISC_RUNNING, &dev->state); } @@ -547,6 +545,7 @@ void dev_activate(struct net_device *dev) void dev_deactivate(struct net_device *dev) { struct Qdisc *qdisc; + struct sk_buff *skb; spin_lock_bh(&dev->queue_lock); qdisc = dev->qdisc; @@ -554,8 +553,12 @@ void dev_deactivate(struct net_device *dev) qdisc_reset(qdisc); + skb = dev->gso_skb; + dev->gso_skb = NULL; spin_unlock_bh(&dev->queue_lock); + kfree_skb(skb); + dev_watchdog_down(dev); /* Wait for outstanding dev_queue_xmit calls. */ @@ -564,11 +567,6 @@ void dev_deactivate(struct net_device *dev) /* Wait for outstanding qdisc_run calls. */ while (test_bit(__LINK_STATE_QDISC_RUNNING, &dev->state)) yield(); - - if (dev->gso_skb) { - kfree_skb(dev->gso_skb); - dev->gso_skb = NULL; - } } void dev_init_scheduler(struct net_device *dev) -- 1.8.2.3