pkt_sched: Add 'deactivated' state.
This new state lets dev_deactivate() mark a qdisc as having been
deactivated.
dev_queue_xmit() and ing_filter() check for this bit and do not
try to process the qdisc if the bit is set.
dev_deactivate() polls the qdisc after setting the bit, waiting
for both __QDISC_STATE_RUNNING and __QDISC_STATE_SCHED to clear.
This isn't perfect yet, but subsequent changesets will make it so.
This part is just one piece of the puzzle.
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/core/dev.c b/net/core/dev.c
index 600bb23..d9e31f6 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -1800,6 +1800,12 @@
spin_lock(root_lock);
+ if (unlikely(test_bit(__QDISC_STATE_DEACTIVATED, &q->state))) {
+ spin_unlock(root_lock);
+ rc = NET_XMIT_DROP;
+ goto out_kfree_skb;
+ }
+
rc = qdisc_enqueue_root(skb, q);
qdisc_run(q);
@@ -2084,7 +2090,8 @@
q = rxq->qdisc;
if (q != &noop_qdisc) {
spin_lock(qdisc_lock(q));
- result = qdisc_enqueue_root(skb, q);
+ if (likely(!test_bit(__QDISC_STATE_DEACTIVATED, &q->state)))
+ result = qdisc_enqueue_root(skb, q);
spin_unlock(qdisc_lock(q));
}