Commit b88948fb authored Mar 16, 2020 by Eric Dumazet Committed by David S. Miller Mar 17, 2020

net_sched: do not reprogram a timer about to expire



qdisc_watchdog_schedule_range_ns() can use the newly added slack
and avoid rearming the hrtimer a bit earlier than the current
value. This patch has no effect if delta_ns parameter
is zero.

Note that this means the max slack is potentially doubled.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

parent efe074c2

net/sched/sch_api.c

+7 −2

Original line number	Diff line number	Diff line
		@@ -625,8 +625,13 @@ void qdisc_watchdog_schedule_range_ns(struct qdisc_watchdog *wd, u64 expires,
		&qdisc_root_sleeping(wd->qdisc)->state))
		return;

		if (wd->last_expires == expires)
		if (hrtimer_is_queued(&wd->timer)) {
		/* If timer is already set in [expires, expires + delta_ns],
		* do not reprogram it.
		*/
		if (wd->last_expires - expires <= delta_ns)
		return;
		}

		wd->last_expires = expires;
		hrtimer_start_range_ns(&wd->timer,

Admin message