From 87b23ea756fdf1f646ae0e037dac90b4d13f4b0f Mon Sep 17 00:00:00 2001 From: Ioana Ciornei Date: Mon, 25 Mar 2019 13:06:22 +0000 Subject: [PATCH] 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: 6147aa64fd23 ("dpaa2-eth: bql support") Signed-off-by: Ioana Ciornei Signed-off-by: David S. Miller --- drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) diff --git a/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c b/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c index 1a68052abb94a..dc339dc1adb21 100644 --- a/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c +++ b/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c @@ -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; -- 2.39.5