net: sched: introduce and use qdisc tree flush/purge helpers

The same code to flush qdisc tree and purge the qdisc queue
is duplicated in many places and in most cases it does not
respect NOLOCK qdisc: the global backlog len is used and the
per CPU values are ignored.

This change addresses the above, factoring-out the relevant
code and using the helpers introduced by the previous patch
to fetch the correct backlog len.

Fixes: c5ad119fb6c0 ("net: sched: pfifo_fast use skb_array")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 2 insertions, 6 deletions

diff --git a/net/sched/sch_prio.c b/net/sched/sch_prio.c
index dfb06d5bfacc..d519b21535b3 100644
--- a/net/sched/sch_prio.c
+++ b/net/sched/sch_prio.c
@@ -216,12 +216,8 @@ static int prio_tune(struct Qdisc *sch, struct nlattr *opt,
 	q->bands = qopt->bands;
 	memcpy(q->prio2band, qopt->priomap, TC_PRIO_MAX+1);
 
-	for (i = q->bands; i < oldbands; i++) {
-		struct Qdisc *child = q->queues[i];
-
-		qdisc_tree_reduce_backlog(child, child->q.qlen,
-					  child->qstats.backlog);
-	}
+	for (i = q->bands; i < oldbands; i++)
+		qdisc_tree_flush_backlog(q->queues[i]);
 
 	for (i = oldbands; i < q->bands; i++) {
 		q->queues[i] = queues[i];