net-next/hinic: Fix a case of Tx Queue is Stopped forever

Fix the following scenario:
1. tx_free_poll is running on cpu X
2. xmit function is running on cpu Y and fails to get sq wqe
3. tx_free_poll frees wqes on cpu X and checks the queue is not stopped
4. xmit function stops the queue after failed to get sq wqe
5. The queue is stopped forever

Signed-off-by: Aviad Krawczyk <aviad.krawczyk@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Aviad Krawczyk 2017-09-27 02:11:33 +08:00 committed by David S. Miller
parent 352f58b0d9
commit bbdc9e687f
1 changed files with 12 additions and 2 deletions

View File

@ -212,10 +212,19 @@ netdev_tx_t hinic_xmit_frame(struct sk_buff *skb, struct net_device *netdev)
sq_wqe = hinic_sq_get_wqe(txq->sq, wqe_size, &prod_idx);
if (!sq_wqe) {
tx_unmap_skb(nic_dev, skb, txq->sges);
netif_stop_subqueue(netdev, qp->q_id);
/* Check for the case free_tx_poll is called in another cpu
* and we stopped the subqueue after free_tx_poll check.
*/
sq_wqe = hinic_sq_get_wqe(txq->sq, wqe_size, &prod_idx);
if (sq_wqe) {
netif_wake_subqueue(nic_dev->netdev, qp->q_id);
goto process_sq_wqe;
}
tx_unmap_skb(nic_dev, skb, txq->sges);
u64_stats_update_begin(&txq->txq_stats.syncp);
txq->txq_stats.tx_busy++;
u64_stats_update_end(&txq->txq_stats.syncp);
@ -223,6 +232,7 @@ netdev_tx_t hinic_xmit_frame(struct sk_buff *skb, struct net_device *netdev)
goto flush_skbs;
}
process_sq_wqe:
hinic_sq_prepare_wqe(txq->sq, prod_idx, sq_wqe, txq->sges, nr_sges);
hinic_sq_write_wqe(txq->sq, prod_idx, sq_wqe, skb, wqe_size);