pkt_sched: Remove smp_wmb() in qdisc_watchdog()

While implementing a TCQ_F_THROTTLED flag there was used an smp_wmb()
in qdisc_watchdog(), but since this flag is practically used only in
sch_netem(), and since it's not even clear what reordering is avoided
here (TCQ_F_THROTTLED vs. __QDISC_STATE_SCHED?) it seems the barrier
could be safely removed.

Signed-off-by: Jarek Poplawski <jarkao2@gmail.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 6bc29e8..0fc4a18 100644 (file)
--- a/net/sched/sch_api.c
+++ b/net/sched/sch_api.c
@@ -450,7 +450,6 @@ static enum hrtimer_restart qdisc_watchdog(struct hrtimer *timer)
                                                 timer);
 
        wd->qdisc->flags &= ~TCQ_F_THROTTLED;
-       smp_wmb();
        __netif_schedule(qdisc_root(wd->qdisc));
 
        return HRTIMER_NORESTART;

diff --git a/net/sched/sch_netem.c b/net/sched/sch_netem.c
index 7e78f1c..d876b87 100644 (file)
--- a/net/sched/sch_netem.c
+++ b/net/sched/sch_netem.c
@@ -266,7 +266,6 @@ static struct sk_buff *netem_dequeue(struct Qdisc *sch)
        struct netem_sched_data *q = qdisc_priv(sch);
        struct sk_buff *skb;
 
-       smp_mb();
        if (sch->flags & TCQ_F_THROTTLED)
                return NULL;