[NET_SCHED] qdisc: avoid transmit softirq on watchdog wakeup
If possible, avoid having to do a transmit softirq when a qdisc
watchdog decides to re-enable. The watchdog routine runs off
a timer, so it is already in the same effective context as
the softirq.
Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/sched/sch_api.c b/net/sched/sch_api.c
index fcaa4ad..5873250 100644
--- a/net/sched/sch_api.c
+++ b/net/sched/sch_api.c
@@ -296,10 +296,16 @@
{
struct qdisc_watchdog *wd = container_of(timer, struct qdisc_watchdog,
timer);
+ struct net_device *dev = wd->qdisc->dev;
wd->qdisc->flags &= ~TCQ_F_THROTTLED;
smp_wmb();
- netif_schedule(wd->qdisc->dev);
+ if (spin_trylock(&dev->queue_lock)) {
+ qdisc_run(dev);
+ spin_unlock(&dev->queue_lock);
+ } else
+ netif_schedule(dev);
+
return HRTIMER_NORESTART;
}