diff options
Diffstat (limited to 'net/sched')
| -rw-r--r-- | net/sched/Kconfig | 10 | ||||
| -rw-r--r-- | net/sched/sch_generic.c | 26 |
2 files changed, 26 insertions, 10 deletions
diff --git a/net/sched/Kconfig b/net/sched/Kconfig index 92435a882fac..9c15c4888d12 100644 --- a/net/sched/Kconfig +++ b/net/sched/Kconfig @@ -2,9 +2,7 @@ # Traffic control configuration. # -menu "QoS and/or fair queueing" - -config NET_SCHED +menuconfig NET_SCHED bool "QoS and/or fair queueing" select NET_SCH_FIFO ---help--- @@ -41,9 +39,6 @@ config NET_SCHED The available schedulers are listed in the following questions; you can say Y to as many as you like. If unsure, say N now. -config NET_SCH_FIFO - bool - if NET_SCHED comment "Queueing/Scheduling" @@ -500,4 +495,5 @@ config NET_CLS_IND endif # NET_SCHED -endmenu +config NET_SCH_FIFO + bool diff --git a/net/sched/sch_generic.c b/net/sched/sch_generic.c index e01d57692c9a..fa1a6f45dc41 100644 --- a/net/sched/sch_generic.c +++ b/net/sched/sch_generic.c @@ -556,6 +556,7 @@ void dev_deactivate(struct net_device *dev) { struct Qdisc *qdisc; struct sk_buff *skb; + int running; spin_lock_bh(&dev->queue_lock); qdisc = dev->qdisc; @@ -571,12 +572,31 @@ void dev_deactivate(struct net_device *dev) dev_watchdog_down(dev); - /* Wait for outstanding dev_queue_xmit calls. */ + /* Wait for outstanding qdisc-less dev_queue_xmit calls. */ synchronize_rcu(); /* Wait for outstanding qdisc_run calls. */ - while (test_bit(__LINK_STATE_QDISC_RUNNING, &dev->state)) - yield(); + do { + while (test_bit(__LINK_STATE_QDISC_RUNNING, &dev->state)) + 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); + + /* + * 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)); } void dev_init_scheduler(struct net_device *dev) |