[dpdk-dev] [PATCH v6 07/25] lib/librte_vhost: patch virtio_dev_merge_tx to return packets to upper layer

[Huawei Xie]

This patch makes virtio_dev_merge_tx return the received packets to  app layer.
Previously virtio_tx_route is called to route these packets and then free them.

Signed-off-by: Huawei Xie <huawei.xie at intel.com>
---
 lib/librte_vhost/vhost_rxtx.c | 12 +++++++-----
 1 file changed, 7 insertions(+), 5 deletions(-)

diff --git a/lib/librte_vhost/vhost_rxtx.c b/lib/librte_vhost/vhost_rxtx.c
index c9e3b1e..07fb085 100644
--- a/lib/librte_vhost/vhost_rxtx.c
+++ b/lib/librte_vhost/vhost_rxtx.c
@@ -512,8 +512,8 @@ virtio_dev_merge_rx(struct virtio_net *dev, struct rte_mbuf 
**pkts,
 }

 /* This function works for TX packets with mergeable feature enabled. */
-static inline void __attribute__((always_inline))
-virtio_dev_merge_tx(struct virtio_net *dev, struct rte_mempool *mbuf_pool)
+static uint16_t void __attribute__((always_inline))
+virtio_dev_merge_tx(struct virtio_net *dev, struct rte_mempool *mbuf_pool, 
struct rte_mbuf **pkts, uint16_t count)
 {
        struct rte_mbuf *m, *prev;
        struct vhost_virtqueue *vq;
@@ -532,7 +532,7 @@ virtio_dev_merge_tx(struct virtio_net *dev, struct 
rte_mempool *mbuf_pool)

        /* If there are no available buffers then return. */
        if (vq->last_used_idx == avail_idx)
-               return;
+               return 0;

        LOG_DEBUG(VHOST_DATA, "(%"PRIu64") virtio_dev_merge_tx()\n",
                dev->device_fh);
@@ -543,6 +543,7 @@ virtio_dev_merge_tx(struct virtio_net *dev, struct 
rte_mempool *mbuf_pool)
        /*get the number of free entries in the ring*/
        free_entries = (avail_idx - vq->last_used_idx);

+       free_entries = RTE_MIN(free_entries, count);
        /* Limit to MAX_PKT_BURST. */
        free_entries = RTE_MIN(free_entries, MAX_PKT_BURST);

@@ -599,7 +600,7 @@ virtio_dev_merge_tx(struct virtio_net *dev, struct 
rte_mempool *mbuf_pool)
                if (unlikely(m == NULL)) {
                        RTE_LOG(ERR, VHOST_DATA,
                                "Failed to allocate memory for mbuf.\n");
-                       return;
+                       return entry_success;
                }

                seg_num++;
@@ -701,9 +702,9 @@ virtio_dev_merge_tx(struct virtio_net *dev, struct 
rte_mempool *mbuf_pool)

                m->nb_segs = seg_num;

+               pkts[entry_success] = m;
                vq->last_used_idx++;
                entry_success++;
-               rte_pktmbuf_free(m);
        }

        rte_compiler_barrier();
@@ -711,5 +712,6 @@ virtio_dev_merge_tx(struct virtio_net *dev, struct 
rte_mempool *mbuf_pool)
        /* Kick guest if required. */
        if (!(vq->avail->flags & VRING_AVAIL_F_NO_INTERRUPT))
                eventfd_write((int)vq->kickfd, 1);
+       return entry_success;

 }
-- 
1.8.1.4