From: Jiayu Hu <jiayu.hu@intel.com>
Date: Mon, 11 Jan 2021 12:16:26 +0000 (-0500)
Subject: vhost: cleanup async enqueue
X-Git-Url: http://git.droids-corp.org/?a=commitdiff_plain;h=9ab57ef196d007a50dc64a50c1c0c9b485bdbdce;p=dpdk.git

vhost: cleanup async enqueue

This patch removes unnecessary check and function calls, and it changes
appropriate types for internal variables and fixes typos.

Signed-off-by: Jiayu Hu <jiayu.hu@intel.com>
Tested-by: Yinan Wang <yinan.wang@intel.com>
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>
---

diff --git a/lib/librte_vhost/rte_vhost_async.h b/lib/librte_vhost/rte_vhost_async.h
index c73bd7c990..03bd55821d 100644
--- a/lib/librte_vhost/rte_vhost_async.h
+++ b/lib/librte_vhost/rte_vhost_async.h
@@ -112,7 +112,7 @@ struct rte_vhost_async_features {
 };
 
 /**
- * register a async channel for vhost
+ * register an async channel for vhost
  *
  * @param vid
  *  vhost device id async channel to be attached to
@@ -147,8 +147,8 @@ __rte_experimental
 int rte_vhost_async_channel_unregister(int vid, uint16_t queue_id);
 
 /**
- * This function submit enqueue data to async engine. This function has
- * no guranttee to the transfer completion upon return. Applications
+ * This function submits enqueue data to async engine. This function has
+ * no guarantee to the transfer completion upon return. Applications
  * should poll transfer status by rte_vhost_poll_enqueue_completed()
  *
  * @param vid
@@ -167,7 +167,7 @@ uint16_t rte_vhost_submit_enqueue_burst(int vid, uint16_t queue_id,
 		struct rte_mbuf **pkts, uint16_t count);
 
 /**
- * This function check async completion status for a specific vhost
+ * This function checks async completion status for a specific vhost
  * device queue. Packets which finish copying (enqueue) operation
  * will be returned in an array.
  *
diff --git a/lib/librte_vhost/virtio_net.c b/lib/librte_vhost/virtio_net.c
index fec08b2623..5ee63fcb67 100644
--- a/lib/librte_vhost/virtio_net.c
+++ b/lib/librte_vhost/virtio_net.c
@@ -1130,8 +1130,12 @@ async_mbuf_to_desc(struct virtio_net *dev, struct vhost_virtqueue *vq,
 	}
 
 out:
-	async_fill_iter(src_it, tlen, src_iovec, tvec_idx);
-	async_fill_iter(dst_it, tlen, dst_iovec, tvec_idx);
+	if (tlen) {
+		async_fill_iter(src_it, tlen, src_iovec, tvec_idx);
+		async_fill_iter(dst_it, tlen, dst_iovec, tvec_idx);
+	} else {
+		src_it->count = 0;
+	}
 
 	return error;
 }
@@ -1491,10 +1495,9 @@ virtio_dev_rx_async_submit_split(struct virtio_net *dev,
 	struct rte_vhost_iov_iter *src_it = it_pool;
 	struct rte_vhost_iov_iter *dst_it = it_pool + 1;
 	uint16_t n_free_slot, slot_idx = 0;
-	uint16_t pkt_err = 0;
 	uint16_t segs_await = 0;
 	struct async_inflight_info *pkts_info = vq->async_pkts_info;
-	int n_pkts = 0;
+	uint32_t n_pkts = 0, pkt_err = 0;
 
 	/*
 	 * The ordering between avail index and desc reads need to be enforced.
@@ -1549,11 +1552,9 @@ virtio_dev_rx_async_submit_split(struct virtio_net *dev,
 		/*
 		 * conditions to trigger async device transfer:
 		 * - buffered packet number reaches transfer threshold
-		 * - this is the last packet in the burst enqueue
 		 * - unused async iov number is less than max vhost vector
 		 */
 		if (pkt_burst_idx >= VHOST_ASYNC_BATCH_THRESHOLD ||
-			(pkt_idx == count - 1 && pkt_burst_idx) ||
 			(VHOST_MAX_ASYNC_VEC / 2 - segs_await <
 			BUF_VECTOR_MAX)) {
 			n_pkts = vq->async_ops.transfer_data(dev->vid,
@@ -1565,7 +1566,7 @@ virtio_dev_rx_async_submit_split(struct virtio_net *dev,
 			segs_await = 0;
 			vq->async_pkts_inflight_n += pkt_burst_idx;
 
-			if (unlikely(n_pkts < (int)pkt_burst_idx)) {
+			if (unlikely(n_pkts < pkt_burst_idx)) {
 				/*
 				 * log error packets number here and do actual
 				 * error processing when applications poll
@@ -1585,7 +1586,7 @@ virtio_dev_rx_async_submit_split(struct virtio_net *dev,
 				queue_id, tdes, 0, pkt_burst_idx);
 		vq->async_pkts_inflight_n += pkt_burst_idx;
 
-		if (unlikely(n_pkts < (int)pkt_burst_idx))
+		if (unlikely(n_pkts < pkt_burst_idx))
 			pkt_err = pkt_burst_idx - n_pkts;
 	}