>From the virtio spec of view, multiple-queue is always enabled/disabled
in queue pairs. DPDK somehow allows the case when Tx and Rx queue number
are different.
Currently, virtio PMD get the queue pair number from the nb_rx_queues
field, which could be an issue when Tx queue number > Rx queue number.
Say, 2 Tx queues and 1 Rx queues. This would end up with 1 quues being
enabled. Which is wrong.
The fix is straightforward. Just pick a bigger number and enable that many
of queues.
Fixes: 823ad647950a ("virtio: support multiple queues")
Signed-off-by: Yuanhan Liu <yuanhan.liu at linux.intel.com>
---
drivers/net/virtio/virtio_ethdev.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/net/virtio/virtio_ethdev.c
b/drivers/net/virtio/virtio_ethdev.c
index 5ec3e0e..d70bd00 100644
--- a/drivers/net/virtio/virtio_ethdev.c
+++ b/drivers/net/virtio/virtio_ethdev.c
@@ -1493,7 +1493,7 @@ virtio_dev_start(struct rte_eth_dev *dev)
*Otherwise the tap backend might already stop its queue due to
fullness.
*vhost backend will have no chance to be waked up
*/
- nb_queues = dev->data->nb_rx_queues;
+ nb_queues = RTE_MAX(dev->data->nb_rx_queues, dev->data->nb_tx_queues);
if (nb_queues > 1) {
if (virtio_set_multiple_queues(dev, nb_queues) != 0)
return -EINVAL;
@@ -1501,7 +1501,7 @@ virtio_dev_start(struct rte_eth_dev *dev)
PMD_INIT_LOG(DEBUG, "nb_queues=%d", nb_queues);
- for (i = 0; i < nb_queues; i++) {
+ for (i = 0; i < dev->data->nb_rx_queues; i++) {
rxvq = dev->data->rx_queues[i];
virtqueue_notify(rxvq->vq);
}
--
1.9.0
