[dpdk-stable] [PATCH 17.11] net/virtio: add barrier in interrupt enable

[Tiwei Bie]

[ backported from upstream commit 8f66bc4ac3c0d4a11252d860f495abd806aa871f ]

Typically, after enabling Rx interrupt, a check should be done
to make sure that there is no new incoming packets before going
to sleep. So a barrier is needed to make sure that any following
check won't happen before the interrupt is actually enabled.

Fixes: c056be239db5 ("net/virtio: add Rx interrupt enable/disable functions")

Signed-off-by: Tiwei Bie <tiwei.bie at intel.com>
Reviewed-by: Maxime Coquelin <maxime.coquelin at redhat.com>
---
 drivers/net/virtio/virtio_ethdev.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/net/virtio/virtio_ethdev.c b/drivers/net/virtio/virtio_ethdev.c
index b3e55ff3b..1bdf37e4b 100644
--- a/drivers/net/virtio/virtio_ethdev.c
+++ b/drivers/net/virtio/virtio_ethdev.c
@@ -739,6 +739,7 @@ virtio_dev_rx_queue_intr_enable(struct rte_eth_dev *dev, uint16_t queue_id)
 	struct virtqueue *vq = rxvq->vq;
 
 	virtqueue_enable_intr(vq);
+	virtio_mb();
 	return 0;
 }
 
-- 
2.17.1