net: caif: avoid using qdisc_qlen() (b0a231a2) · Commits · 戴 / test

Such helper does not cope correctly with NOLOCK qdiscs. In the following patches we will move back qlen to per CPU values for such qdiscs, so qdisc_qlen_sum() is not an option, too. Instead, use qlen only for lock qdiscs, and always set flow off for NOLOCK qdiscs with a not empty tx queue. Signed-off-by:

Paolo Abeni <pabeni@redhat.com> Signed-off-by:

David S. Miller <davem@davemloft.net>

net/caif/caif_dev.c

+8 −4

Original line number	Diff line number	Diff line
		@@ -186,15 +186,19 @@ static int transmit(struct cflayer layer, struct cfpkt pkt)
		goto noxoff;

		if (likely(!netif_queue_stopped(caifd->netdev))) {
		struct Qdisc *sch;

		/* If we run with a TX queue, check if the queue is too long*/
		txq = netdev_get_tx_queue(skb->dev, 0);
		qlen = qdisc_qlen(rcu_dereference_bh(txq->qdisc));

		if (likely(qlen == 0))
		sch = rcu_dereference_bh(txq->qdisc);
		if (likely(qdisc_is_empty(sch)))
		goto noxoff;

		/* can check for explicit qdisc len value only !NOLOCK,
		* always set flow off otherwise
		*/
		high = (caifd->netdev->tx_queue_len * q_high) / 100;
		if (likely(qlen < high))
		if (!(sch->flags & TCQ_F_NOLOCK) && likely(sch->q.qlen < high))
		goto noxoff;
		}

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