[dpdk-dev] [PATCH v3 2/7] net/netvsc: implement rx/tx descriptor status functions

[Stephen Hemminger]

These functions are useful for applications and debugging.
The netvsc PMD also transparently handles the rx/tx descriptor
functions for underlying VF device.

Signed-off-by: Stephen Hemminger <stephen at networkplumber.org>
---
 drivers/net/netvsc/hn_ethdev.c |  3 ++
 drivers/net/netvsc/hn_rxtx.c   | 57 ++++++++++++++++++++++++++++++++++
 drivers/net/netvsc/hn_var.h    |  5 +++
 3 files changed, 65 insertions(+)

diff --git a/drivers/net/netvsc/hn_ethdev.c b/drivers/net/netvsc/hn_ethdev.c
index b890fa3befa8..675a49e66a57 100644
--- a/drivers/net/netvsc/hn_ethdev.c
+++ b/drivers/net/netvsc/hn_ethdev.c
@@ -875,8 +875,11 @@ static const struct eth_dev_ops hn_eth_dev_ops = {
 	.tx_queue_setup		= hn_dev_tx_queue_setup,
 	.tx_queue_release	= hn_dev_tx_queue_release,
 	.tx_done_cleanup        = hn_dev_tx_done_cleanup,
+	.tx_descriptor_status	= hn_dev_tx_descriptor_status,
 	.rx_queue_setup		= hn_dev_rx_queue_setup,
 	.rx_queue_release	= hn_dev_rx_queue_release,
+	.rx_queue_count		= hn_dev_rx_queue_count,
+	.rx_descriptor_status   = hn_dev_rx_queue_status,
 	.link_update		= hn_dev_link_update,
 	.stats_get		= hn_dev_stats_get,
 	.stats_reset            = hn_dev_stats_reset,
diff --git a/drivers/net/netvsc/hn_rxtx.c b/drivers/net/netvsc/hn_rxtx.c
index 668f48fcbf15..b22d8ea7feb0 100644
--- a/drivers/net/netvsc/hn_rxtx.c
+++ b/drivers/net/netvsc/hn_rxtx.c
@@ -369,6 +369,29 @@ hn_dev_tx_queue_release(void *arg)
 	rte_free(txq);
 }
 
+/*
+ * Check the status of a Tx descriptor in the queue.
+ *
+ * returns:
+ *  - -EINVAL              - offset outside of tx_descriptor pool.
+ *  - RTE_ETH_TX_DESC_FULL - descriptor is not acknowleged by host.
+ *  - RTE_ETH_TX_DESC_DONE - descriptor is available.
+ */
+int hn_dev_tx_descriptor_status(void *arg, uint16_t offset)
+{
+	const struct hn_tx_queue *txq = arg;
+
+	hn_process_events(txq->hv, txq->queue_id, 0);
+
+	if (offset >= rte_mempool_avail_count(txq->txdesc_pool))
+		return -EINVAL;
+
+	if (offset < rte_mempool_in_use_count(txq->txdesc_pool))
+		return RTE_ETH_TX_DESC_FULL;
+	else
+		return RTE_ETH_TX_DESC_DONE;
+}
+
 static void
 hn_nvs_send_completed(struct rte_eth_dev *dev, uint16_t queue_id,
 		      unsigned long xactid, const struct hn_nvs_rndis_ack *ack)
@@ -966,6 +989,40 @@ hn_dev_rx_queue_release(void *arg)
 	hn_rx_queue_free(rxq, true);
 }
 
+/*
+ * Get the number of used descriptor in a rx queue
+ * For this device that means how many packets are pending in the ring.
+ */
+uint32_t
+hn_dev_rx_queue_count(struct rte_eth_dev *dev, uint16_t queue_id)
+{
+	struct hn_rx_queue *rxq = dev->data->rx_queues[queue_id];
+
+	return rte_ring_count(rxq->rx_ring);
+}
+
+/*
+ * Check the status of a Rx descriptor in the queue
+ *
+ * returns:
+ *  - -EINVAL               - offset outside of ring
+ *  - RTE_ETH_RX_DESC_AVAIL - no data available yet
+ *  - RTE_ETH_RX_DESC_DONE  - data is waiting in stagin ring
+ */
+int hn_dev_rx_queue_status(void *arg, uint16_t offset)
+{
+	const struct hn_rx_queue *rxq = arg;
+
+	hn_process_events(rxq->hv, rxq->queue_id, 0);
+	if (offset >= rxq->rx_ring->capacity)
+		return -EINVAL;
+
+	if (offset < rte_ring_count(rxq->rx_ring))
+		return RTE_ETH_RX_DESC_DONE;
+	else
+		return RTE_ETH_RX_DESC_AVAIL;
+}
+
 int
 hn_dev_tx_done_cleanup(void *arg, uint32_t free_cnt)
 {
diff --git a/drivers/net/netvsc/hn_var.h b/drivers/net/netvsc/hn_var.h
index 93168d2e0102..ded0d4c60a04 100644
--- a/drivers/net/netvsc/hn_var.h
+++ b/drivers/net/netvsc/hn_var.h
@@ -169,6 +169,7 @@ void	hn_dev_tx_queue_release(void *arg);
 void	hn_dev_tx_queue_info(struct rte_eth_dev *dev, uint16_t queue_idx,
 			     struct rte_eth_txq_info *qinfo);
 int	hn_dev_tx_done_cleanup(void *arg, uint32_t free_cnt);
+int	hn_dev_tx_descriptor_status(void *arg, uint16_t offset);
 
 struct hn_rx_queue *hn_rx_queue_alloc(struct hn_data *hv,
 				      uint16_t queue_id,
@@ -181,6 +182,8 @@ int	hn_dev_rx_queue_setup(struct rte_eth_dev *dev,
 void	hn_dev_rx_queue_info(struct rte_eth_dev *dev, uint16_t queue_id,
 			     struct rte_eth_rxq_info *qinfo);
 void	hn_dev_rx_queue_release(void *arg);
+uint32_t hn_dev_rx_queue_count(struct rte_eth_dev *dev, uint16_t queue_id);
+int	hn_dev_rx_queue_status(void *rxq, uint16_t offset);
 void	hn_dev_free_queues(struct rte_eth_dev *dev);
 
 /* Check if VF is attached */
@@ -231,6 +234,8 @@ int	hn_vf_tx_queue_setup(struct rte_eth_dev *dev,
 			     unsigned int socket_id,
 			     const struct rte_eth_txconf *tx_conf);
 void	hn_vf_tx_queue_release(struct hn_data *hv, uint16_t queue_id);
+int	hn_vf_tx_queue_status(struct hn_data *hv, uint16_t queue_id, uint16_t offset);
+
 int	hn_vf_rx_queue_setup(struct rte_eth_dev *dev,
 			     uint16_t queue_idx, uint16_t nb_desc,
 			     unsigned int socket_id,
-- 
2.26.2