[03/10] net/virtio: add missing barrier in interrupt enable

Message ID 20190319064312.13743-4-tiwei.bie@intel.com (mailing list archive)
State Accepted, archived
Delegated to: Maxime Coquelin
Headers
Series net/virtio: cleanups and fixes for packed/split ring |

Checks

Context Check Description
ci/Intel-compilation success Compilation OK
ci/checkpatch success coding style OK

Commit Message

Tiwei Bie March 19, 2019, 6:43 a.m. UTC
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")
Cc: stable@dpdk.org

Signed-off-by: Tiwei Bie <tiwei.bie@intel.com>
---
 drivers/net/virtio/virtio_ethdev.c | 2 ++
 1 file changed, 2 insertions(+)
  

Comments

Maxime Coquelin March 19, 2019, 12:49 p.m. UTC | #1
On 3/19/19 7:43 AM, Tiwei Bie wrote:
> 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")
> Cc: stable@dpdk.org
> 
> Signed-off-by: Tiwei Bie <tiwei.bie@intel.com>
> ---
>   drivers/net/virtio/virtio_ethdev.c | 2 ++
>   1 file changed, 2 insertions(+)


Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>

Thanks,
Maxime
  

Patch

diff --git a/drivers/net/virtio/virtio_ethdev.c b/drivers/net/virtio/virtio_ethdev.c
index 78ba7bd29..ff16fb63e 100644
--- a/drivers/net/virtio/virtio_ethdev.c
+++ b/drivers/net/virtio/virtio_ethdev.c
@@ -850,10 +850,12 @@  virtio_mtu_set(struct rte_eth_dev *dev, uint16_t mtu)
 static int
 virtio_dev_rx_queue_intr_enable(struct rte_eth_dev *dev, uint16_t queue_id)
 {
+	struct virtio_hw *hw = dev->data->dev_private;
 	struct virtnet_rx *rxvq = dev->data->rx_queues[queue_id];
 	struct virtqueue *vq = rxvq->vq;
 
 	virtqueue_enable_intr(vq);
+	virtio_mb(hw->weak_barriers);
 	return 0;
 }