ethdev: support unidirectional configuration

User should be able to configure ethdev with zero rx/tx queues,
but both should not be zero.
After above change, rte_eth_dev_tx_queue_config,
rte_eth_dev_rx_queue_config should allocate memory for rx/tx queues only
when number of rx/tx queues are nonzero.

Signed-off-by: Reshma Pattan <reshma.pattan@intel.com>
Acked-by: Konstantin Ananyev <konstantin.ananyev@intel.com>

diff --git a/lib/librte_ether/rte_ethdev.c b/lib/librte_ether/rte_ethdev.c
index 6506757..1257965 100644 (file)
--- a/lib/librte_ether/rte_ethdev.c
+++ b/lib/librte_ether/rte_ethdev.c
@@ -671,7 +671,7 @@ rte_eth_dev_rx_queue_config(struct rte_eth_dev *dev, uint16_t nb_queues)
        void **rxq;
        unsigned i;
 
-       if (dev->data->rx_queues == NULL) { /* first time configuration */
+       if (dev->data->rx_queues == NULL && nb_queues != 0) { /* first time configuration */
                dev->data->rx_queues = rte_zmalloc("ethdev->rx_queues",
                                sizeof(dev->data->rx_queues[0]) * nb_queues,
                                RTE_CACHE_LINE_SIZE);
@@ -679,7 +679,7 @@ rte_eth_dev_rx_queue_config(struct rte_eth_dev *dev, uint16_t nb_queues)
                        dev->data->nb_rx_queues = 0;
                        return -(ENOMEM);
                }
-       } else { /* re-configure */
+       } else if (dev->data->rx_queues != NULL && nb_queues != 0) { /* re-configure */
                RTE_FUNC_PTR_OR_ERR_RET(*dev->dev_ops->rx_queue_release, -ENOTSUP);
 
                rxq = dev->data->rx_queues;
@@ -699,6 +699,13 @@ rte_eth_dev_rx_queue_config(struct rte_eth_dev *dev, uint16_t nb_queues)
 
                dev->data->rx_queues = rxq;
 
+       } else if (dev->data->rx_queues != NULL && nb_queues == 0) {
+               RTE_FUNC_PTR_OR_ERR_RET(*dev->dev_ops->rx_queue_release, -ENOTSUP);
+
+               rxq = dev->data->rx_queues;
+
+               for (i = nb_queues; i < old_nb_queues; i++)
+                       (*dev->dev_ops->rx_queue_release)(rxq[i]);
        }
        dev->data->nb_rx_queues = nb_queues;
        return 0;
@@ -815,7 +822,7 @@ rte_eth_dev_tx_queue_config(struct rte_eth_dev *dev, uint16_t nb_queues)
        void **txq;
        unsigned i;
 
-       if (dev->data->tx_queues == NULL) { /* first time configuration */
+       if (dev->data->tx_queues == NULL && nb_queues != 0) { /* first time configuration */
                dev->data->tx_queues = rte_zmalloc("ethdev->tx_queues",
                                                   sizeof(dev->data->tx_queues[0]) * nb_queues,
                                                   RTE_CACHE_LINE_SIZE);
@@ -823,7 +830,7 @@ rte_eth_dev_tx_queue_config(struct rte_eth_dev *dev, uint16_t nb_queues)
                        dev->data->nb_tx_queues = 0;
                        return -(ENOMEM);
                }
-       } else { /* re-configure */
+       } else if (dev->data->tx_queues != NULL && nb_queues != 0) { /* re-configure */
                RTE_FUNC_PTR_OR_ERR_RET(*dev->dev_ops->tx_queue_release, -ENOTSUP);
 
                txq = dev->data->tx_queues;
@@ -843,6 +850,13 @@ rte_eth_dev_tx_queue_config(struct rte_eth_dev *dev, uint16_t nb_queues)
 
                dev->data->tx_queues = txq;
 
+       } else if (dev->data->tx_queues != NULL && nb_queues == 0) {
+               RTE_FUNC_PTR_OR_ERR_RET(*dev->dev_ops->tx_queue_release, -ENOTSUP);
+
+               txq = dev->data->tx_queues;
+
+               for (i = nb_queues; i < old_nb_queues; i++)
+                       (*dev->dev_ops->tx_queue_release)(txq[i]);
        }
        dev->data->nb_tx_queues = nb_queues;
        return 0;
@@ -889,25 +903,23 @@ rte_eth_dev_configure(uint8_t port_id, uint16_t nb_rx_q, uint16_t nb_tx_q,
         * configured device.
         */
        (*dev->dev_ops->dev_infos_get)(dev, &dev_info);
+
+       if (nb_rx_q == 0 && nb_tx_q == 0) {
+               RTE_PMD_DEBUG_TRACE("ethdev port_id=%d both rx and tx queue cannot be 0\n", port_id);
+               return -EINVAL;
+       }
+
        if (nb_rx_q > dev_info.max_rx_queues) {
                RTE_PMD_DEBUG_TRACE("ethdev port_id=%d nb_rx_queues=%d > %d\n",
                                port_id, nb_rx_q, dev_info.max_rx_queues);
                return -EINVAL;
        }
-       if (nb_rx_q == 0) {
-               RTE_PMD_DEBUG_TRACE("ethdev port_id=%d nb_rx_q == 0\n", port_id);
-               return -EINVAL;
-       }
 
        if (nb_tx_q > dev_info.max_tx_queues) {
                RTE_PMD_DEBUG_TRACE("ethdev port_id=%d nb_tx_queues=%d > %d\n",
                                port_id, nb_tx_q, dev_info.max_tx_queues);
                return -EINVAL;
        }
-       if (nb_tx_q == 0) {
-               RTE_PMD_DEBUG_TRACE("ethdev port_id=%d nb_tx_q == 0\n", port_id);
-               return -EINVAL;
-       }
 
        /* Copy the dev_conf parameter into the dev structure */
        memcpy(&dev->data->dev_conf, dev_conf, sizeof(dev->data->dev_conf));