Re: [dpdk-dev] [PATCH] vhost: add vDPA resource cleanup callback

[Maxime Coquelin]

Hi Xueming,

On 10/19/21 13:39, Xueming Li wrote:

This patch adds vDPA device cleanup callback to release resources on
vhost user connection close.

Signed-off-by: Xueming Li <xuemi...@nvidia.com>
---
  lib/vhost/rte_vdpa_dev.h | 3 +++
  lib/vhost/vhost_user.c   | 6 ++++++
  2 files changed, 9 insertions(+)

diff --git a/lib/vhost/rte_vdpa_dev.h b/lib/vhost/rte_vdpa_dev.h
index b0f494815fa..2711004fe05 100644
--- a/lib/vhost/rte_vdpa_dev.h
+++ b/lib/vhost/rte_vdpa_dev.h
@@ -32,6 +32,9 @@ struct rte_vdpa_dev_ops {
        /** Driver close the device (Mandatory) */
        int (*dev_close)(int vid);

+ /** Connection closed, clean up resources */

+       int (*dev_cleanup)(int vid);
+
        /** Enable/disable this vring (Mandatory) */
        int (*set_vring_state)(int vid, int vring, int state);

diff --git a/lib/vhost/vhost_user.c b/lib/vhost/vhost_user.c

index 5a894ca0cc7..032b621c86c 100644
--- a/lib/vhost/vhost_user.c
+++ b/lib/vhost/vhost_user.c
@@ -162,6 +162,12 @@ free_mem_region(struct virtio_net *dev)
  void
  vhost_backend_cleanup(struct virtio_net *dev)
  {
+       struct rte_vdpa_device *vdpa_dev;
+
+       vdpa_dev = dev->vdpa_dev;
+       if (vdpa_dev && vdpa_dev->ops->dev_cleanup != NULL)
+               vdpa_dev->ops->dev_cleanup(dev->vid);
+
        if (dev->mem) {
                free_mem_region(dev);
                rte_free(dev->mem);

What will be done there that cannot be done in .dev_close()?
Having the mlx5 implementation of this callback alongside this patch may
help to understand.

Thanks,
Maxime