[PATCH 09/16] vhost: add few more functions

[Yuanhan Liu <yuanhan.liu@linux.intel.com>]

Add few more functions to export few more fields or informations of
virtio_net struct, to applications, as we are gonna make them private.
It includes:

- rte_vhost_avail_entries
  It's actually a rename of "rte_vring_available_entries", with the
  "vring" to "vhost" name change to keep the consistency of other
  functions.

- rte_vhost_get_queue_num
  Exports the "virt_qp_nb" field.

- rte_vhost_get_numa_node
  Exports the numa node from where the virtio net device is allocated.

Signed-off-by: Yuanhan Liu <yuanhan.liu@linux.intel.com>
---
 drivers/net/vhost/rte_eth_vhost.c | 18 ++++---------
 examples/vhost/main.c             |  4 +--
 lib/librte_vhost/rte_virtio_net.h | 37 +++++++++++++++++++++++++++
 lib/librte_vhost/virtio-net.c     | 54 +++++++++++++++++++++++++++++++++++++++
 4 files changed, 98 insertions(+), 15 deletions(-)

diff --git a/drivers/net/vhost/rte_eth_vhost.c b/drivers/net/vhost/rte_eth_vhost.c
index 290fd9e..9763cd4 100644
--- a/drivers/net/vhost/rte_eth_vhost.c
+++ b/drivers/net/vhost/rte_eth_vhost.c
@@ -33,9 +33,6 @@
 #include <unistd.h>
 #include <pthread.h>
 #include <stdbool.h>
-#ifdef RTE_LIBRTE_VHOST_NUMA
-#include <numaif.h>
-#endif
 
 #include <rte_mbuf.h>
 #include <rte_ethdev.h>
@@ -228,7 +225,7 @@ new_device(struct virtio_net *dev)
 	struct vhost_queue *vq;
 	unsigned i;
 #ifdef RTE_LIBRTE_VHOST_NUMA
-	int newnode, ret;
+	int newnode;
 #endif
 
 	if (dev == NULL) {
@@ -247,14 +244,9 @@ new_device(struct virtio_net *dev)
 	internal->vid = dev->vid;
 
 #ifdef RTE_LIBRTE_VHOST_NUMA
-	ret  = get_mempolicy(&newnode, NULL, 0, dev,
-			MPOL_F_NODE | MPOL_F_ADDR);
-	if (ret < 0) {
-		RTE_LOG(ERR, PMD, "Unknown numa node\n");
-		return -1;
-	}
-
-	eth_dev->data->numa_node = newnode;
+	newnode = rte_vhost_get_numa_node(dev->vid);
+	if (newnode > 0)
+		eth_dev->data->numa_node = newnode;
 #endif
 
 	for (i = 0; i < eth_dev->data->nb_rx_queues; i++) {
@@ -274,7 +266,7 @@ new_device(struct virtio_net *dev)
 		vq->port = eth_dev->data->port_id;
 	}
 
-	for (i = 0; i < dev->virt_qp_nb * VIRTIO_QNUM; i++)
+	for (i = 0; i < rte_vhost_get_queue_num(dev->vid) * VIRTIO_QNUM; i++)
 		rte_vhost_enable_guest_notification(dev, i, 0);
 
 	dev->priv = eth_dev;
diff --git a/examples/vhost/main.c b/examples/vhost/main.c
index e395e4a..145fa6f 100644
--- a/examples/vhost/main.c
+++ b/examples/vhost/main.c
@@ -1056,13 +1056,13 @@ drain_eth_rx(struct vhost_dev *vdev)
 	 * to diminish packet loss.
 	 */
 	if (enable_retry &&
-	    unlikely(rx_count > rte_vring_available_entries(dev,
+	    unlikely(rx_count > rte_vhost_avail_entries(vdev->vid,
 			VIRTIO_RXQ))) {
 		uint32_t retry;
 
 		for (retry = 0; retry < burst_rx_retry_num; retry++) {
 			rte_delay_us(burst_rx_delay_time);
-			if (rx_count <= rte_vring_available_entries(dev,
+			if (rx_count <= rte_vhost_avail_entries(vdev->vid,
 					VIRTIO_RXQ))
 				break;
 		}
diff --git a/lib/librte_vhost/rte_virtio_net.h b/lib/librte_vhost/rte_virtio_net.h
index bc64e89..27f6847 100644
--- a/lib/librte_vhost/rte_virtio_net.h
+++ b/lib/librte_vhost/rte_virtio_net.h
@@ -245,6 +245,43 @@ int rte_vhost_driver_callback_register(struct virtio_net_device_ops const * cons
 int rte_vhost_driver_session_start(void);
 
 /**
+ * Get how many avail entries are left in the queue @queue_id.
+ *
+ * @param vid
+ *  virtio-net device ID
+ * @param queue_id
+ *  virtio queue index in mq case
+ *
+ * @return
+ *  num of avail entires left
+ */
+uint16_t rte_vhost_avail_entries(int vid, uint16_t queue_id);
+
+/**
+ * Get the number of queues the device supports.
+ *
+ * @param vid
+ *  virtio-net device ID
+ *
+ * @return
+ *  The number of queues, 0 on failure
+ */
+uint32_t rte_vhost_get_queue_num(int vid);
+
+/**
+ * Get the numa node from which the virtio net device's memory
+ * is allocated.
+ *
+ * @param vid
+ *  virtio-net device ID
+ *
+ * @return
+ *  The numa node, -1 on failure
+ */
+int rte_vhost_get_numa_node(int vid);
+
+
+/**
  * This function adds buffers to the virtio devices RX virtqueue. Buffers can
  * be received from the physical port or from another virtual device. A packet
  * count is returned to indicate the number of packets that were succesfully
diff --git a/lib/librte_vhost/virtio-net.c b/lib/librte_vhost/virtio-net.c
index ea28090..6bf4d87 100644
--- a/lib/librte_vhost/virtio-net.c
+++ b/lib/librte_vhost/virtio-net.c
@@ -753,6 +753,60 @@ int rte_vhost_feature_disable(uint64_t feature_mask)
 	return 0;
 }
 
+uint16_t
+rte_vhost_avail_entries(int vid, uint16_t queue_id)
+{
+	struct virtio_net *dev;
+	struct vhost_virtqueue *vq;
+
+	dev = get_device(vid);
+	if (!dev)
+		return 0;
+
+	vq = dev->virtqueue[queue_id];
+	if (!vq->enabled)
+		return 0;
+
+	return *(volatile uint16_t *)&vq->avail->idx - vq->last_used_idx_res;
+}
+
+uint32_t
+rte_vhost_get_queue_num(int vid)
+{
+	struct virtio_net *dev = get_device(vid);
+
+	if (dev == NULL)
+		return 0;
+
+	return dev->virt_qp_nb;
+}
+
+int
+rte_vhost_get_numa_node(int vid)
+{
+#ifdef RTE_LIBRTE_VHOST_NUMA
+	struct virtio_net *dev = get_device(vid);
+	int numa_node;
+	int ret;
+
+	if (dev == NULL)
+		return -1;
+
+	ret = get_mempolicy(&numa_node, NULL, 0, dev,
+			MPOL_F_NODE | MPOL_F_ADDR);
+	if (ret < 0) {
+		RTE_LOG(ERR, VHOST_CONFIG,
+			"(%d) failed to query numa node: %d\n", vid, ret);
+		return -1;
+	}
+
+	return numa_node;
+#else
+	RTE_SET_USED(vid);
+	return -1;
+#endif
+}
+
 int rte_vhost_feature_enable(uint64_t feature_mask)
 {
 	if ((feature_mask & VHOST_SUPPORTED_FEATURES) == feature_mask) {
-- 
1.9.0