Re: [dpdk-dev] [PATCH v2] net/virtio-user: fix multiple queues fail in server mode

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

On Thu, May 10, 2018 at 05:36:23PM +0800, zhiyong.yang@intel.com wrote:
> This patch fixes multiple queues failure when virtio-user works in
> server mode.
> 
> This patch adds feature negotiation in the processing of virtio-user
> reccnnection.

typo: reccnnection

> 
> Fixes: bd8f50a45d0f ("net/virtio-user: support server mode")
> 
> Signed-off-by: Zhiyong Yang <zhiyong.yang@intel.com>
> ---
> 
> Changes in V2:
> 1. fix a comment typo.
> 2. add feature negotiation in the processing of reconnection.
> 
>  drivers/net/virtio/virtio_user/vhost_user.c      |  3 +++
>  drivers/net/virtio/virtio_user/virtio_user_dev.c | 14 ++++++++++----
>  drivers/net/virtio/virtio_user_ethdev.c          | 20 ++++++++++++++++++++
>  3 files changed, 33 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/net/virtio/virtio_user/vhost_user.c b/drivers/net/virtio/virtio_user/vhost_user.c
> index a6df97a..93e4d92 100644
> --- a/drivers/net/virtio/virtio_user/vhost_user.c
> +++ b/drivers/net/virtio/virtio_user/vhost_user.c
> @@ -263,6 +263,9 @@ struct hugepage_file_info {
>  
>  	PMD_DRV_LOG(INFO, "%s", vhost_msg_strings[req]);
>  
> +	if (dev->is_server && vhostfd < 0)
> +		return -1;
> +
>  	msg.request = req;
>  	msg.flags = VHOST_USER_VERSION;
>  	msg.size = 0;
> diff --git a/drivers/net/virtio/virtio_user/virtio_user_dev.c b/drivers/net/virtio/virtio_user/virtio_user_dev.c
> index 38b8bc9..b7e1915 100644
> --- a/drivers/net/virtio/virtio_user/virtio_user_dev.c
> +++ b/drivers/net/virtio/virtio_user/virtio_user_dev.c
> @@ -447,10 +447,16 @@ int virtio_user_stop_device(struct virtio_user_dev *dev)
>  		return -1;
>  	}
>  
> -	for (i = 0; i < q_pairs; ++i)
> -		ret |= dev->ops->enable_qp(dev, i, 1);
> -	for (i = q_pairs; i < dev->max_queue_pairs; ++i)
> -		ret |= dev->ops->enable_qp(dev, i, 0);
> +	/* Server mode can't enable queue pairs if vhostfd is invalid,
> +	 * always return 0 in this case.
> +	 */
> +	if (dev->vhostfd >= 0)  {
> +		for (i = 0; i < q_pairs; ++i)
> +			ret |= dev->ops->enable_qp(dev, i, 1);
> +		for (i = q_pairs; i < dev->max_queue_pairs; ++i)
> +			ret |= dev->ops->enable_qp(dev, i, 0);
> +	} else if (!dev->is_server)
> +		ret = ~0;

You need to find a chance to enable these queue pairs
when the connection is established.

>  
>  	dev->queue_pairs = q_pairs;
>  
> diff --git a/drivers/net/virtio/virtio_user_ethdev.c b/drivers/net/virtio/virtio_user_ethdev.c
> index 4e7b3c3..91a0c44 100644
> --- a/drivers/net/virtio/virtio_user_ethdev.c
> +++ b/drivers/net/virtio/virtio_user_ethdev.c
> @@ -30,6 +30,7 @@
>  	int ret;
>  	int flag;
>  	int connectfd;
> +	uint64_t features = dev->device_features, status;
>  	struct rte_eth_dev *eth_dev = &rte_eth_devices[dev->port_id];
>  
>  	connectfd = accept(dev->listenfd, NULL, NULL);
> @@ -37,6 +38,25 @@
>  		return -1;
>  
>  	dev->vhostfd = connectfd;
> +	if (dev->ops->send_request(dev, VHOST_USER_GET_FEATURES,
> +				   &dev->device_features) < 0) {
> +		PMD_INIT_LOG(ERR, "get_features failed: %s",
> +			     strerror(errno));
> +		return -1;
> +	}
> +
> +	status = features & ~dev->device_features;

There is no need to introduce `status`.

> +	/* For following bits, vhost-user doesn't really need to know */
> +	status &= ~(1ull << VIRTIO_NET_F_MAC);
> +	status &= ~(1ull << VIRTIO_NET_F_CTRL_VLAN);
> +	status &= ~(1ull << VIRTIO_NET_F_CTRL_MAC_ADDR);
> +	status &= ~(1ull << VIRTIO_NET_F_STATUS);
> +	if (status)
> +		PMD_INIT_LOG(ERR, "WARNING: Some features (0x%lx) are not supported by vhost-user!",

You will want to use PRIx64 here.

Thanks

> +			     status);
> +
> +	dev->features &= dev->device_features;
> +
>  	flag = fcntl(connectfd, F_GETFD);
>  	fcntl(connectfd, F_SETFL, flag | O_NONBLOCK);
>  
> -- 
> 1.8.3.1
>