[dpdk-dev] [PATCH v3 2/4] vhost: dynamically allocate async memory

[Patrick Fu <patrick.fu@intel.com>]

Allocate async internal memory buffer by rte_malloc(), replacing array
declaration inside vq structure. Dynamic allocation can help to save
memory footprint when async path is not registered.

Signed-off-by: Patrick Fu <patrick.fu@intel.com>
---
 lib/librte_vhost/vhost.c | 69 ++++++++++++++++++++++++++--------------
 lib/librte_vhost/vhost.h |  4 +--
 2 files changed, 47 insertions(+), 26 deletions(-)

diff --git a/lib/librte_vhost/vhost.c b/lib/librte_vhost/vhost.c
index eca507836..05b578c2f 100644
--- a/lib/librte_vhost/vhost.c
+++ b/lib/librte_vhost/vhost.c
@@ -324,6 +324,24 @@ cleanup_device(struct virtio_net *dev, int destroy)
 	}
 }
 
+static void
+vhost_free_async_mem(struct vhost_virtqueue *vq)
+{
+	if (vq->async_pkts_pending)
+		rte_free(vq->async_pkts_pending);
+	if (vq->async_pkts_info)
+		rte_free(vq->async_pkts_info);
+	if (vq->it_pool)
+		rte_free(vq->it_pool);
+	if (vq->vec_pool)
+		rte_free(vq->vec_pool);
+
+	vq->async_pkts_pending = NULL;
+	vq->async_pkts_info = NULL;
+	vq->it_pool = NULL;
+	vq->vec_pool = NULL;
+}
+
 void
 free_vq(struct virtio_net *dev, struct vhost_virtqueue *vq)
 {
@@ -331,10 +349,7 @@ free_vq(struct virtio_net *dev, struct vhost_virtqueue *vq)
 		rte_free(vq->shadow_used_packed);
 	else {
 		rte_free(vq->shadow_used_split);
-		if (vq->async_pkts_pending)
-			rte_free(vq->async_pkts_pending);
-		if (vq->async_pkts_info)
-			rte_free(vq->async_pkts_info);
+		vhost_free_async_mem(vq);
 	}
 	rte_free(vq->batch_copy_elems);
 	rte_mempool_free(vq->iotlb_pool);
@@ -1538,6 +1553,7 @@ int rte_vhost_async_channel_register(int vid, uint16_t queue_id,
 	struct vhost_virtqueue *vq;
 	struct virtio_net *dev = get_device(vid);
 	struct rte_vhost_async_features f;
+	int node;
 
 	if (dev == NULL || ops == NULL)
 		return -1;
@@ -1570,19 +1586,32 @@ int rte_vhost_async_channel_register(int vid, uint16_t queue_id,
 		goto reg_out;
 	}
 
-	vq->async_pkts_pending = rte_malloc(NULL,
+#ifdef RTE_LIBRTE_VHOST_NUMA
+	if (get_mempolicy(&node, NULL, 0, vq, MPOL_F_NODE | MPOL_F_ADDR)) {
+		VHOST_LOG_CONFIG(ERR,
+			"unable to get numa information in async register. "
+			"allocating async buffer memory on the caller thread node\n");
+		node = SOCKET_ID_ANY;
+	}
+#else
+	node = SOCKET_ID_ANY;
+#endif
+
+	vq->async_pkts_pending = rte_malloc_socket(NULL,
 			vq->size * sizeof(uintptr_t),
-			RTE_CACHE_LINE_SIZE);
-	vq->async_pkts_info = rte_malloc(NULL,
+			RTE_CACHE_LINE_SIZE, node);
+	vq->async_pkts_info = rte_malloc_socket(NULL,
 			vq->size * sizeof(struct async_inflight_info),
-			RTE_CACHE_LINE_SIZE);
-	if (!vq->async_pkts_pending || !vq->async_pkts_info) {
-		if (vq->async_pkts_pending)
-			rte_free(vq->async_pkts_pending);
-
-		if (vq->async_pkts_info)
-			rte_free(vq->async_pkts_info);
-
+			RTE_CACHE_LINE_SIZE, node);
+	vq->it_pool = rte_malloc_socket(NULL,
+			VHOST_MAX_ASYNC_IT * sizeof(struct rte_vhost_iov_iter),
+			RTE_CACHE_LINE_SIZE, node);
+	vq->vec_pool = rte_malloc_socket(NULL,
+			VHOST_MAX_ASYNC_VEC * sizeof(struct iovec),
+			RTE_CACHE_LINE_SIZE, node);
+	if (!vq->async_pkts_pending || !vq->async_pkts_info ||
+		!vq->it_pool || !vq->vec_pool) {
+		vhost_free_async_mem(vq);
 		VHOST_LOG_CONFIG(ERR,
 				"async register failed: cannot allocate memory for vq data "
 				"(vid %d, qid: %d)\n", vid, queue_id);
@@ -1630,15 +1659,7 @@ int rte_vhost_async_channel_unregister(int vid, uint16_t queue_id)
 		goto out;
 	}
 
-	if (vq->async_pkts_pending) {
-		rte_free(vq->async_pkts_pending);
-		vq->async_pkts_pending = NULL;
-	}
-
-	if (vq->async_pkts_info) {
-		rte_free(vq->async_pkts_info);
-		vq->async_pkts_info = NULL;
-	}
+	vhost_free_async_mem(vq);
 
 	vq->async_ops.transfer_data = NULL;
 	vq->async_ops.check_completed_copies = NULL;
diff --git a/lib/librte_vhost/vhost.h b/lib/librte_vhost/vhost.h
index 155a832c1..f0ee00c73 100644
--- a/lib/librte_vhost/vhost.h
+++ b/lib/librte_vhost/vhost.h
@@ -218,8 +218,8 @@ struct vhost_virtqueue {
 	/* operation callbacks for async dma */
 	struct rte_vhost_async_channel_ops	async_ops;
 
-	struct rte_vhost_iov_iter it_pool[VHOST_MAX_ASYNC_IT];
-	struct iovec vec_pool[VHOST_MAX_ASYNC_VEC];
+	struct rte_vhost_iov_iter *it_pool;
+	struct iovec *vec_pool;
 
 	/* async data transfer status */
 	uintptr_t	**async_pkts_pending;
-- 
2.18.4