Re: [dpdk-dev] [PATCH v3 20/21] net/virtio: add support for event suppression

[Tiwei Bie <tiwei.bie@intel.com>]

On Thu, Apr 05, 2018 at 12:10:30PM +0200, Jens Freimann wrote:
> Signed-off-by: Jens Freimann <jfreimann@redhat.com>
> ---
>  drivers/net/virtio/virtio_ethdev.c |  2 +-
>  drivers/net/virtio/virtio_ethdev.h |  2 +-
>  drivers/net/virtio/virtio_rxtx.c   | 15 +++++++-
>  drivers/net/virtio/virtqueue.h     | 73 ++++++++++++++++++++++++++++++++++++--
>  4 files changed, 86 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/net/virtio/virtio_ethdev.c b/drivers/net/virtio/virtio_ethdev.c
> index a3c3376d7..65a6a9d89 100644
> --- a/drivers/net/virtio/virtio_ethdev.c
> +++ b/drivers/net/virtio/virtio_ethdev.c
> @@ -727,7 +727,7 @@ virtio_dev_rx_queue_intr_enable(struct rte_eth_dev *dev, uint16_t queue_id)
>  	struct virtnet_rx *rxvq = dev->data->rx_queues[queue_id];
>  	struct virtqueue *vq = rxvq->vq;
>  
> -	virtqueue_enable_intr(vq);
> +	virtqueue_enable_intr(vq, 0, 0);
>  	return 0;
>  }
>  
> diff --git a/drivers/net/virtio/virtio_ethdev.h b/drivers/net/virtio/virtio_ethdev.h
> index 3aeced4bb..19d3f2617 100644
> --- a/drivers/net/virtio/virtio_ethdev.h
> +++ b/drivers/net/virtio/virtio_ethdev.h
> @@ -37,7 +37,7 @@
>  	 1u << VIRTIO_RING_F_INDIRECT_DESC |    \
>  	 1ULL << VIRTIO_F_VERSION_1       |	\
>  	 1ULL << VIRTIO_F_RING_PACKED     |	\
> -	 1ULL << VIRTIO_F_IOMMU_PLATFORM)

Why remove this feature bit?


> +	 1ULL << VIRTIO_RING_F_EVENT_IDX)

Supporting event suppression doesn't means supporting
F_EVENT_IDX. Event suppression is mandatory and not
a negotiable feature. F_EVENT_IDX is just an optional
enhancement for event suppression.


>  
>  #define VIRTIO_PMD_SUPPORTED_GUEST_FEATURES	\
>  	(VIRTIO_PMD_DEFAULT_GUEST_FEATURES |	\
> diff --git a/drivers/net/virtio/virtio_rxtx.c b/drivers/net/virtio/virtio_rxtx.c
> index a48ca6aaa..ed65434ce 100644
> --- a/drivers/net/virtio/virtio_rxtx.c
> +++ b/drivers/net/virtio/virtio_rxtx.c
> @@ -127,6 +127,10 @@ virtio_xmit_pkts_packed(void *tx_queue, struct rte_mbuf **tx_pkts,
>  
>  		rte_smp_wmb();
>  		_set_desc_avail(&desc[head_idx], wrap_counter);
> +		if (unlikely(virtqueue_kick_prepare_packed(vq))) {
> +				virtqueue_notify(vq);
> +				PMD_RX_LOG(DEBUG, "Notified");

The indent isn't right.


> +		}
>  	}
[...]