[dpdk-dev] [PATCH v1 1/4] net/virtio: remove unnecessary rmb barrier

[Joyce Kong]

As desc_is_used has a load-acquire or rte_io_rmb inside
and wait for used desc in virtqueue, it is ok to remove
virtio_rmb behind it.

Signed-off-by: Joyce Kong <joyce.kong at arm.com>
Reviewed-by: Ruifeng Wang <ruifeng.wang at arm.com>
---
 drivers/net/virtio/virtio_ethdev.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/net/virtio/virtio_ethdev.c b/drivers/net/virtio/virtio_ethdev.c
index 6c233b75b..0d91f7a50 100644
--- a/drivers/net/virtio/virtio_ethdev.c
+++ b/drivers/net/virtio/virtio_ethdev.c
@@ -209,12 +209,12 @@ virtio_send_command_packed(struct virtnet_ctl *cvq,
 	virtio_wmb(vq->hw->weak_barriers);
 	virtqueue_notify(vq);
 
-	/* wait for used descriptors in virtqueue */
+	/* wait for used desc in virtqueue
+	 * desc_is_used has a load-acquire or rte_io_rmb inside
+	 */
 	while (!desc_is_used(&desc[head], vq))
 		usleep(100);
 
-	virtio_rmb(vq->hw->weak_barriers);
-
 	/* now get used descriptors */
 	vq->vq_free_cnt += nb_descs;
 	vq->vq_used_cons_idx += nb_descs;
-- 
2.29.2