vhost: clear shadow used table index at flush time

Signed-off-by: Maxime Coquelin <maxime.coquelin@redhat.com>
Acked-by: Tiwei Bie <tiwei.bie@intel.com>

diff --git a/lib/librte_vhost/virtio_net.c b/lib/librte_vhost/virtio_net.c
index 82d5d9e..d6b3089 100644 (file)
--- a/lib/librte_vhost/virtio_net.c
+++ b/lib/librte_vhost/virtio_net.c
@@ -115,6 +115,7 @@ flush_shadow_used_ring(struct virtio_net *dev, struct vhost_virtqueue *vq)
        vhost_log_cache_sync(dev, vq);
 
        *(volatile uint16_t *)&vq->used->idx += vq->shadow_used_idx;
+       vq->shadow_used_idx = 0;
        vhost_log_used_vring(dev, vq, offsetof(struct vring_used, idx),
                sizeof(vq->used->idx));
 }
@@ -567,7 +568,6 @@ virtio_dev_rx(struct virtio_net *dev, uint16_t queue_id,
 
        rte_prefetch0(&vq->avail->ring[vq->last_avail_idx & (vq->size - 1)]);
 
-       vq->shadow_used_idx = 0;
        avail_head = *((volatile uint16_t *)&vq->avail->idx);
        for (pkt_idx = 0; pkt_idx < count; pkt_idx++) {
                uint32_t pkt_len = pkts[pkt_idx]->pkt_len + dev->vhost_hlen;
@@ -1055,7 +1055,6 @@ rte_vhost_dequeue_burst(int vid, uint16_t queue_id,
                goto out_access_unlock;
 
        vq->batch_copy_nb_elems = 0;
-       vq->shadow_used_idx = 0;
 
        if (dev->features & (1ULL << VIRTIO_F_IOMMU_PLATFORM))
                vhost_user_iotlb_rd_lock(vq);
@@ -1086,7 +1085,6 @@ rte_vhost_dequeue_burst(int vid, uint16_t queue_id,
 
                flush_shadow_used_ring(dev, vq);
                vhost_vring_call(dev, vq);
-               vq->shadow_used_idx = 0;
        }
 
        rte_prefetch0(&vq->avail->ring[vq->last_avail_idx & (vq->size - 1)]);