[dpdk-dev] [PATCH v5 resend 03/12] vhost: vring queue setup for multiple queue support

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

All queue pairs, including the default (the first) queue pair,
are allocated dynamically, when a vring_call message is received
first time for a specific queue pair.

This is a refactor work for enabling vhost-user multiple queue;
it should not break anything as it does no functional changes:
we don't support mq set, so there is only one mq at max.

This patch is based on Changchun's patch.

Signed-off-by: Yuanhan Liu <yuanhan.liu@linux.intel.com>
---
 lib/librte_vhost/rte_virtio_net.h             |   3 +-
 lib/librte_vhost/vhost_user/virtio-net-user.c |  44 +++++-----
 lib/librte_vhost/virtio-net.c                 | 121 ++++++++++++++++----------
 3 files changed, 102 insertions(+), 66 deletions(-)

diff --git a/lib/librte_vhost/rte_virtio_net.h b/lib/librte_vhost/rte_virtio_net.h
index e3a21e5..5dd6493 100644
--- a/lib/librte_vhost/rte_virtio_net.h
+++ b/lib/librte_vhost/rte_virtio_net.h
@@ -96,7 +96,7 @@ struct vhost_virtqueue {
  * Device structure contains all configuration information relating to the device.
  */
 struct virtio_net {
-	struct vhost_virtqueue	*virtqueue[VIRTIO_QNUM];	/**< Contains all virtqueue information. */
+	struct vhost_virtqueue	*virtqueue[VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MAX];	/**< Contains all virtqueue information. */
 	struct virtio_memory	*mem;		/**< QEMU memory and memory region information. */
 	uint64_t		features;	/**< Negotiated feature set. */
 	uint64_t		protocol_features;	/**< Negotiated protocol feature set. */
@@ -104,6 +104,7 @@ struct virtio_net {
 	uint32_t		flags;		/**< Device flags. Only used to check if device is running on data core. */
 #define IF_NAME_SZ (PATH_MAX > IFNAMSIZ ? PATH_MAX : IFNAMSIZ)
 	char			ifname[IF_NAME_SZ];	/**< Name of the tap device or socket path. */
+	uint32_t		virt_qp_nb;	/**< number of queue pair we have allocated */
 	void			*priv;		/**< private context */
 } __rte_cache_aligned;
 
diff --git a/lib/librte_vhost/vhost_user/virtio-net-user.c b/lib/librte_vhost/vhost_user/virtio-net-user.c
index 360254e..e83d279 100644
--- a/lib/librte_vhost/vhost_user/virtio-net-user.c
+++ b/lib/librte_vhost/vhost_user/virtio-net-user.c
@@ -206,25 +206,33 @@ err_mmap:
 }
 
 static int
+vq_is_ready(struct vhost_virtqueue *vq)
+{
+	return vq && vq->desc   &&
+	       vq->kickfd != -1 &&
+	       vq->callfd != -1;
+}
+
+static int
 virtio_is_ready(struct virtio_net *dev)
 {
 	struct vhost_virtqueue *rvq, *tvq;
+	uint32_t i;
 
-	/* mq support in future.*/
-	rvq = dev->virtqueue[VIRTIO_RXQ];
-	tvq = dev->virtqueue[VIRTIO_TXQ];
-	if (rvq && tvq && rvq->desc && tvq->desc &&
-		(rvq->kickfd != -1) &&
-		(rvq->callfd != -1) &&
-		(tvq->kickfd != -1) &&
-		(tvq->callfd != -1)) {
-		RTE_LOG(INFO, VHOST_CONFIG,
-			"virtio is now ready for processing.\n");
-		return 1;
+	for (i = 0; i < dev->virt_qp_nb; i++) {
+		rvq = dev->virtqueue[i * VIRTIO_QNUM + VIRTIO_RXQ];
+		tvq = dev->virtqueue[i * VIRTIO_QNUM + VIRTIO_TXQ];
+
+		if (!vq_is_ready(rvq) || !vq_is_ready(tvq)) {
+			RTE_LOG(INFO, VHOST_CONFIG,
+				"virtio is not ready for processing.\n");
+			return 0;
+		}
 	}
+
 	RTE_LOG(INFO, VHOST_CONFIG,
-		"virtio isn't ready for processing.\n");
-	return 0;
+		"virtio is now ready for processing.\n");
+	return 1;
 }
 
 void
@@ -290,13 +298,9 @@ user_get_vring_base(struct vhost_device_ctx ctx,
 	 * sent and only sent in vhost_vring_stop.
 	 * TODO: cleanup the vring, it isn't usable since here.
 	 */
-	if ((dev->virtqueue[VIRTIO_RXQ]->kickfd) >= 0) {
-		close(dev->virtqueue[VIRTIO_RXQ]->kickfd);
-		dev->virtqueue[VIRTIO_RXQ]->kickfd = -1;
-	}
-	if ((dev->virtqueue[VIRTIO_TXQ]->kickfd) >= 0) {
-		close(dev->virtqueue[VIRTIO_TXQ]->kickfd);
-		dev->virtqueue[VIRTIO_TXQ]->kickfd = -1;
+	if ((dev->virtqueue[state->index]->kickfd) >= 0) {
+		close(dev->virtqueue[state->index]->kickfd);
+		dev->virtqueue[state->index]->kickfd = -1;
 	}
 
 	return 0;
diff --git a/lib/librte_vhost/virtio-net.c b/lib/librte_vhost/virtio-net.c
index deac6b9..643a92e 100644
--- a/lib/librte_vhost/virtio-net.c
+++ b/lib/librte_vhost/virtio-net.c
@@ -36,6 +36,7 @@
 #include <stddef.h>
 #include <stdint.h>
 #include <stdlib.h>
+#include <assert.h>
 #include <sys/mman.h>
 #include <unistd.h>
 #ifdef RTE_LIBRTE_VHOST_NUMA
@@ -178,6 +179,15 @@ add_config_ll_entry(struct virtio_net_config_ll *new_ll_dev)
 
 }
 
+static void
+cleanup_vq(struct vhost_virtqueue *vq)
+{
+	if (vq->callfd >= 0)
+		close(vq->callfd);
+	if (vq->kickfd >= 0)
+		close(vq->kickfd);
+}
+
 /*
  * Unmap any memory, close any file descriptors and
  * free any memory owned by a device.
@@ -185,6 +195,8 @@ add_config_ll_entry(struct virtio_net_config_ll *new_ll_dev)
 static void
 cleanup_device(struct virtio_net *dev)
 {
+	uint32_t i;
+
 	/* Unmap QEMU memory file if mapped. */
 	if (dev->mem) {
 		munmap((void *)(uintptr_t)dev->mem->mapped_address,
@@ -192,15 +204,10 @@ cleanup_device(struct virtio_net *dev)
 		free(dev->mem);
 	}
 
-	/* Close any event notifiers opened by device. */
-	if (dev->virtqueue[VIRTIO_RXQ]->callfd >= 0)
-		close(dev->virtqueue[VIRTIO_RXQ]->callfd);
-	if (dev->virtqueue[VIRTIO_RXQ]->kickfd >= 0)
-		close(dev->virtqueue[VIRTIO_RXQ]->kickfd);
-	if (dev->virtqueue[VIRTIO_TXQ]->callfd >= 0)
-		close(dev->virtqueue[VIRTIO_TXQ]->callfd);
-	if (dev->virtqueue[VIRTIO_TXQ]->kickfd >= 0)
-		close(dev->virtqueue[VIRTIO_TXQ]->kickfd);
+	for (i = 0; i < dev->virt_qp_nb; i++) {
+		cleanup_vq(dev->virtqueue[i * VIRTIO_QNUM + VIRTIO_RXQ]);
+		cleanup_vq(dev->virtqueue[i * VIRTIO_QNUM + VIRTIO_TXQ]);
+	}
 }
 
 /*
@@ -209,9 +216,11 @@ cleanup_device(struct virtio_net *dev)
 static void
 free_device(struct virtio_net_config_ll *ll_dev)
 {
-	/* Free any malloc'd memory */
-	rte_free(ll_dev->dev.virtqueue[VIRTIO_RXQ]);
-	rte_free(ll_dev->dev.virtqueue[VIRTIO_TXQ]);
+	uint32_t i;
+
+	for (i = 0; i < ll_dev->dev.virt_qp_nb; i++)
+		rte_free(ll_dev->dev.virtqueue[i * VIRTIO_QNUM]);
+
 	rte_free(ll_dev);
 }
 
@@ -244,6 +253,50 @@ rm_config_ll_entry(struct virtio_net_config_ll *ll_dev,
 	}
 }
 
+static void
+init_vring_queue(struct vhost_virtqueue *vq)
+{
+	memset(vq, 0, sizeof(struct vhost_virtqueue));
+
+	vq->kickfd = -1;
+	vq->callfd = -1;
+
+	/* Backends are set to -1 indicating an inactive device. */
+	vq->backend = -1;
+}
+
+static void
+init_vring_queue_pair(struct virtio_net *dev, uint32_t qp_idx)
+{
+	init_vring_queue(dev->virtqueue[qp_idx * VIRTIO_QNUM + VIRTIO_RXQ]);
+	init_vring_queue(dev->virtqueue[qp_idx * VIRTIO_QNUM + VIRTIO_TXQ]);
+}
+
+static int
+alloc_vring_queue_pair(struct virtio_net *dev, uint32_t qp_idx)
+{
+	struct vhost_virtqueue *virtqueue = NULL;
+	uint32_t virt_rx_q_idx = qp_idx * VIRTIO_QNUM + VIRTIO_RXQ;
+	uint32_t virt_tx_q_idx = qp_idx * VIRTIO_QNUM + VIRTIO_TXQ;
+
+	virtqueue = rte_malloc(NULL,
+			       sizeof(struct vhost_virtqueue) * VIRTIO_QNUM, 0);
+	if (virtqueue == NULL) {
+		RTE_LOG(ERR, VHOST_CONFIG,
+			"Failed to allocate memory for virt qp:%d.\n", qp_idx);
+		return -1;
+	}
+
+	dev->virtqueue[virt_rx_q_idx] = virtqueue;
+	dev->virtqueue[virt_tx_q_idx] = virtqueue + VIRTIO_TXQ;
+
+	init_vring_queue_pair(dev, qp_idx);
+
+	dev->virt_qp_nb += 1;
+
+	return 0;
+}
+
 /*
  *  Initialise all variables in device structure.
  */
@@ -251,6 +304,7 @@ static void
 init_device(struct virtio_net *dev)
 {
 	uint64_t vq_offset;
+	uint32_t i;
 
 	/*
 	 * Virtqueues have already been malloced so
@@ -261,17 +315,9 @@ init_device(struct virtio_net *dev)
 	/* Set everything to 0. */
 	memset((void *)(uintptr_t)((uint64_t)(uintptr_t)dev + vq_offset), 0,
 		(sizeof(struct virtio_net) - (size_t)vq_offset));
-	memset(dev->virtqueue[VIRTIO_RXQ], 0, sizeof(struct vhost_virtqueue));
-	memset(dev->virtqueue[VIRTIO_TXQ], 0, sizeof(struct vhost_virtqueue));
 
-	dev->virtqueue[VIRTIO_RXQ]->kickfd = -1;
-	dev->virtqueue[VIRTIO_RXQ]->callfd = -1;
-	dev->virtqueue[VIRTIO_TXQ]->kickfd = -1;
-	dev->virtqueue[VIRTIO_TXQ]->callfd = -1;
-
-	/* Backends are set to -1 indicating an inactive device. */
-	dev->virtqueue[VIRTIO_RXQ]->backend = VIRTIO_DEV_STOPPED;
-	dev->virtqueue[VIRTIO_TXQ]->backend = VIRTIO_DEV_STOPPED;
+	for (i = 0; i < dev->virt_qp_nb; i++)
+		init_vring_queue_pair(dev, i);
 }
 
 /*
@@ -283,7 +329,6 @@ static int
 new_device(struct vhost_device_ctx ctx)
 {
 	struct virtio_net_config_ll *new_ll_dev;
-	struct vhost_virtqueue *virtqueue_rx, *virtqueue_tx;
 
 	/* Setup device and virtqueues. */
 	new_ll_dev = rte_malloc(NULL, sizeof(struct virtio_net_config_ll), 0);
@@ -294,28 +339,6 @@ new_device(struct vhost_device_ctx ctx)
 		return -1;
 	}
 
-	virtqueue_rx = rte_malloc(NULL, sizeof(struct vhost_virtqueue), 0);
-	if (virtqueue_rx == NULL) {
-		rte_free(new_ll_dev);
-		RTE_LOG(ERR, VHOST_CONFIG,
-			"(%"PRIu64") Failed to allocate memory for rxq.\n",
-			ctx.fh);
-		return -1;
-	}
-
-	virtqueue_tx = rte_malloc(NULL, sizeof(struct vhost_virtqueue), 0);
-	if (virtqueue_tx == NULL) {
-		rte_free(virtqueue_rx);
-		rte_free(new_ll_dev);
-		RTE_LOG(ERR, VHOST_CONFIG,
-			"(%"PRIu64") Failed to allocate memory for txq.\n",
-			ctx.fh);
-		return -1;
-	}
-
-	new_ll_dev->dev.virtqueue[VIRTIO_RXQ] = virtqueue_rx;
-	new_ll_dev->dev.virtqueue[VIRTIO_TXQ] = virtqueue_tx;
-
 	/* Initialise device and virtqueues. */
 	init_device(&new_ll_dev->dev);
 
@@ -680,13 +703,21 @@ set_vring_call(struct vhost_device_ctx ctx, struct vhost_vring_file *file)
 {
 	struct virtio_net *dev;
 	struct vhost_virtqueue *vq;
+	uint32_t cur_qp_idx = file->index / VIRTIO_QNUM;
 
 	dev = get_device(ctx);
 	if (dev == NULL)
 		return -1;
 
+	/* alloc vring queue pair if it is a new queue pair */
+	if (cur_qp_idx + 1 > dev->virt_qp_nb) {
+		if (alloc_vring_queue_pair(dev, cur_qp_idx) < 0)
+			return -1;
+	}
+
 	/* file->index refers to the queue index. The txq is 1, rxq is 0. */
 	vq = dev->virtqueue[file->index];
+	assert(vq != NULL);
 
 	if (vq->callfd >= 0)
 		close(vq->callfd);
-- 
1.9.0