Re: [dpdk-dev] [PATCH v6 13/15] vhost: add Tx support for packed ring

[Maxime Coquelin]

On 07/04/2018 07:45 AM, Tiwei Bie wrote:
On Mon, Jul 02, 2018 at 10:16:27AM +0200, Maxime Coquelin wrote:
Signed-off-by: Maxime Coquelin <maxime.coque...@redhat.com>
---
  lib/librte_vhost/vhost.h      |   1 +
  lib/librte_vhost/virtio_net.c | 121 +++++++++++++++++++++++++++++++++++++++++-
  2 files changed, 121 insertions(+), 1 deletion(-)

diff --git a/lib/librte_vhost/vhost.h b/lib/librte_vhost/vhost.h
index a7320469a..6ea8fb896 100644
--- a/lib/librte_vhost/vhost.h
+++ b/lib/librte_vhost/vhost.h
@@ -56,6 +56,7 @@ struct buf_vector {
  struct zcopy_mbuf {
        struct rte_mbuf *mbuf;
        uint32_t desc_idx;
+       uint16_t desc_count;
        uint16_t in_use;
  
  	TAILQ_ENTRY(zcopy_mbuf) next;
diff --git a/lib/librte_vhost/virtio_net.c b/lib/librte_vhost/virtio_net.c
index 2e286e228..03dd38235 100644
--- a/lib/librte_vhost/virtio_net.c
+++ b/lib/librte_vhost/virtio_net.c
@@ -1445,6 +1445,122 @@ virtio_dev_tx_split(struct virtio_net *dev, struct 
vhost_virtqueue *vq,
        return i;
  }
  
+static __rte_always_inline uint16_t
+virtio_dev_tx_packed(struct virtio_net *dev, struct vhost_virtqueue *vq,
+       struct rte_mempool *mbuf_pool, struct rte_mbuf **pkts, uint16_t count)
+{
+       uint16_t i;
+
+       rte_prefetch0(&vq->desc_packed[vq->last_avail_idx]);
+
+       if (unlikely(dev->dequeue_zero_copy)) {
+               struct zcopy_mbuf *zmbuf, *next;
+               int nr_updated = 0;
+
+               for (zmbuf = TAILQ_FIRST(&vq->zmbuf_list);
+                    zmbuf != NULL; zmbuf = next) {
+                       next = TAILQ_NEXT(zmbuf, next);
+
+                       if (mbuf_is_consumed(zmbuf->mbuf)) {
+                               update_shadow_used_ring_packed(vq,
+                                               zmbuf->desc_idx,
+                                               0,
+                                               zmbuf->desc_count);
+                               nr_updated += 1;

nr_updated isn't really used.

Right, it seems it should be removed in the _split version too, but I'll 
do that in a separate patch.

Thanks,
Maxime
+
+                               TAILQ_REMOVE(&vq->zmbuf_list, zmbuf, next);
+                               restore_mbuf(zmbuf->mbuf);
+                               rte_pktmbuf_free(zmbuf->mbuf);
+                               put_zmbuf(zmbuf);
+                               vq->nr_zmbuf -= 1;
+                       }
+               }
+
+               flush_shadow_used_ring_packed(dev, vq);
+               vhost_vring_call(dev, vq);
+       }
+
[...]