net: sched: avoid costly atomic operation in fq_dequeue()
Standard qdisc API to setup a timer implies an atomic operation on every
packet dequeue : qdisc_unthrottled()
It turns out this is not really needed for FQ, as FQ has no concept of
global qdisc throttling, being a qdisc handling many different flows,
some of them can be throttled, while others are not.
Fix is straightforward : add a 'bool throttle' to
qdisc_watchdog_schedule_ns(), and remove calls to qdisc_unthrottled()
in sch_fq.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/sched/sch_api.c b/net/sched/sch_api.c
index c79a226..2cf61b3 100644
--- a/net/sched/sch_api.c
+++ b/net/sched/sch_api.c
@@ -594,13 +594,14 @@
}
EXPORT_SYMBOL(qdisc_watchdog_init);
-void qdisc_watchdog_schedule_ns(struct qdisc_watchdog *wd, u64 expires)
+void qdisc_watchdog_schedule_ns(struct qdisc_watchdog *wd, u64 expires, bool throttle)
{
if (test_bit(__QDISC_STATE_DEACTIVATED,
&qdisc_root_sleeping(wd->qdisc)->state))
return;
- qdisc_throttled(wd->qdisc);
+ if (throttle)
+ qdisc_throttled(wd->qdisc);
hrtimer_start(&wd->timer,
ns_to_ktime(expires),