Commit 8c838f53 authored by Ioana Ciornei's avatar Ioana Ciornei Committed by David S. Miller
Browse files

dpaa2-eth: fix race condition with bql frame accounting 



It might happen that Tx conf acknowledges a frame before it was
subscribed in bql, as subscribing was previously done after the enqueue
operation.

This patch moves the netdev_tx_sent_queue call before the actual frame
enqueue, so that this can never happen.

Fixes: 569dac6a ("dpaa2-eth: bql support")
Signed-off-by: default avatarIoana Ciornei <ioana.ciornei@nxp.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 047a013f

drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c

+9 −4
Original line number Diff line number Diff line
@@ -815,6 +815,14 @@ static netdev_tx_t dpaa2_eth_tx(struct sk_buff *skb, struct net_device *net_dev) 
	 */

	queue_mapping = skb_get_queue_mapping(skb);

	fq = &priv->fq[queue_mapping];



	fd_len = dpaa2_fd_get_len(&fd);

	nq = netdev_get_tx_queue(net_dev, queue_mapping);

	netdev_tx_sent_queue(nq, fd_len);



	/* Everything that happens after this enqueues might race with

	 * the Tx confirmation callback for this frame

	 */

	for (i = 0; i < DPAA2_ETH_ENQUEUE_RETRIES; i++) {

		err = priv->enqueue(priv, fq, &fd, 0);

		if (err != -EBUSY)
@@ -825,13 +833,10 @@ static netdev_tx_t dpaa2_eth_tx(struct sk_buff *skb, struct net_device *net_dev) 
		percpu_stats->tx_errors++;

		/* Clean up everything, including freeing the skb */

		free_tx_fd(priv, fq, &fd, false);

		netdev_tx_completed_queue(nq, 1, fd_len);

	} else {

		fd_len = dpaa2_fd_get_len(&fd);

		percpu_stats->tx_packets++;

		percpu_stats->tx_bytes += fd_len;



		nq = netdev_get_tx_queue(net_dev, queue_mapping);

		netdev_tx_sent_queue(nq, fd_len);

	}



	return NETDEV_TX_OK;

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