pkt_sched: Convert qdisc_watchdog to tasklet_hrtimer

None of this stuff should execute in hw IRQ context, therefore
use a tasklet_hrtimer so that it runs in softirq context.
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Thomas Gleixner <tglx@linutronix.de>

include/net/pkt_sched.h

@@ -61,8 +61,8 @@ psched_tdiff_bounded(psched_time_t tv1, psched_time_t tv2, psched_time_t bound)
 }
 
 struct qdisc_watchdog {
-	struct hrtimer	timer;
-	struct Qdisc	*qdisc;
+	struct tasklet_hrtimer	timer;
+	struct Qdisc		*qdisc;
 };
 
 extern void qdisc_watchdog_init(struct qdisc_watchdog *wd, struct Qdisc *qdisc);

net/sched/sch_api.c

@@ -468,8 +468,8 @@ static enum hrtimer_restart qdisc_watchdog(struct hrtimer *timer)
 
 void qdisc_watchdog_init(struct qdisc_watchdog *wd, struct Qdisc *qdisc)
 {
-	hrtimer_init(&wd->timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS);
-	wd->timer.function = qdisc_watchdog;
+	tasklet_hrtimer_init(&wd->timer, qdisc_watchdog,
+			     CLOCK_MONOTONIC, HRTIMER_MODE_ABS);
 	wd->qdisc = qdisc;
 }
 EXPORT_SYMBOL(qdisc_watchdog_init);
@@ -485,13 +485,13 @@ void qdisc_watchdog_schedule(struct qdisc_watchdog *wd, psched_time_t expires)
 	wd->qdisc->flags |= TCQ_F_THROTTLED;
 	time = ktime_set(0, 0);
 	time = ktime_add_ns(time, PSCHED_TICKS2NS(expires));
-	hrtimer_start(&wd->timer, time, HRTIMER_MODE_ABS);
+	tasklet_hrtimer_start(&wd->timer, time, HRTIMER_MODE_ABS);
 }
 EXPORT_SYMBOL(qdisc_watchdog_schedule);
 
 void qdisc_watchdog_cancel(struct qdisc_watchdog *wd)
 {
-	hrtimer_cancel(&wd->timer);
+	tasklet_hrtimer_cancel(&wd->timer);
 	wd->qdisc->flags &= ~TCQ_F_THROTTLED;
 }
 EXPORT_SYMBOL(qdisc_watchdog_cancel);