From: Ioana Ciornei Date: Mon, 25 Mar 2019 13:06:22 +0000 (+0000) Subject: dpaa2-eth: fix race condition with bql frame accounting X-Git-Tag: v5.15~6702^2 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=8c838f53e149871561a9261ac768a9c7071b43d0;p=platform%2Fkernel%2Flinux-starfive.git 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: 569dac6a5a0d ("dpaa2-eth: bql support") Signed-off-by: Ioana Ciornei Signed-off-by: David S. Miller --- diff --git a/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c b/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c index 1a68052..dc339dc 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;