[dpdk-dev] [PATCH v2 3/5] vhost: handle memory hotplug with vDPA devices

[Xia, Chenbo]

> -----Original Message-----
> From: dev <dev-bounces at dpdk.org> On Behalf Of Matan Azrad
> Sent: Thursday, June 25, 2020 9:38 PM
> To: Maxime Coquelin <maxime.coquelin at redhat.com>
> Cc: dev at dpdk.org; Wang, Xiao W <xiao.w.wang at intel.com>
> Subject: [dpdk-dev] [PATCH v2 3/5] vhost: handle memory hotplug with vDPA
> devices
> 
> Some vDPA drivers' basic configurations should be updated when the guest
> memory is hotplugged.
> 
> Close vDPA device before hotplug operation and recreate it after the hotplug
> operation is done.
> 
> Signed-off-by: Matan Azrad <matan at mellanox.com>
> ---
>  lib/librte_vhost/vhost_user.c | 9 +++++++++
>  1 file changed, 9 insertions(+)
> 
> diff --git a/lib/librte_vhost/vhost_user.c b/lib/librte_vhost/vhost_user.c index
> b90fc78..f690fdb 100644
> --- a/lib/librte_vhost/vhost_user.c
> +++ b/lib/librte_vhost/vhost_user.c
> @@ -1073,6 +1073,15 @@
>  	}
> 
>  	if (dev->mem) {
> +		if (dev->flags & VIRTIO_DEV_VDPA_CONFIGURED) {
> +			int did = dev->vdpa_dev_id;
> +			struct rte_vdpa_device *vdpa_dev =
> +						rte_vdpa_get_device(did);
> +
> +			if (vdpa_dev && vdpa_dev->ops->dev_close)
> +				vdpa_dev->ops->dev_close(dev->vid);
> +			dev->flags &= ~VIRTIO_DEV_VDPA_CONFIGURED;
> +		}

For now, this solution is general for all vendors. Later we may improve this by calling vendor's
callback as they may behave differently. For now this looks good to me :) (sorry that the reply
is late for memory hotplug discussion because of holiday). Thanks!

>  		free_mem_region(dev);
>  		rte_free(dev->mem);
>  		dev->mem = NULL;
> --
> 1.8.3.1

Reviewed-by: Chenbo Xia <chenbo.xia at intel.com>