net/virtio: replace full barrier with relaxed ones for Arm

Relax the full write barriers to one-way barriers for virtio
control path for Arm platform

Signed-off-by: Joyce Kong <joyce.kong@arm.com>
Reviewed-by: Ruifeng Wang <ruifeng.wang@arm.com>
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>

diff --git a/drivers/net/virtio/virtio_ethdev.c b/drivers/net/virtio/virtio_ethdev.c
index 9600624d082b5fbd91f48247e7692031ded08ba1..92a3d4efa58162a09f16c188ae4b294c979b0ca2 100644 (file)
--- a/drivers/net/virtio/virtio_ethdev.c
+++ b/drivers/net/virtio/virtio_ethdev.c
@@ -203,8 +203,8 @@ virtio_send_command_packed(struct virtnet_ctl *cvq,
                vq->vq_packed.cached_flags ^= VRING_PACKED_DESC_F_AVAIL_USED;
        }
 
-       virtio_wmb(vq->hw->weak_barriers);
-       desc[head].flags = VRING_DESC_F_NEXT | flags;
+       virtqueue_store_flags_packed(&desc[head], VRING_DESC_F_NEXT | flags,
+                       vq->hw->weak_barriers);
 
        virtio_wmb(vq->hw->weak_barriers);
        virtqueue_notify(vq);