Re: [PATCH v5 3/3] vdpa/mlx5: Add support for reading descriptor statistics

[Si-Wei Liu]

On 5/11/2022 10:25 AM, Si-Wei Liu wrote:
> > +
> > +static int mlx5_vdpa_get_vendor_vq_stats(struct vdpa_device *vdev, 
> > u16 idx,
> > +                     struct sk_buff *msg,
> > +                     struct netlink_ext_ack *extack)
> > +{
> > +    struct mlx5_vdpa_dev *mvdev = to_mvdev(vdev);
> > +    struct mlx5_vdpa_net *ndev = to_mlx5_vdpa_ndev(mvdev);
> > +    struct mlx5_vdpa_virtqueue *mvq;
> > +    struct mlx5_control_vq *cvq;
> > +    u64 received_desc;
> > +    u64 completed_desc;
> > +    int err = 0;
> > +    u16 max_vqp;
> > +
> > +    mutex_lock(&ndev->reslock);
> I wonder if we can change this lock to r/w semaphore too, otherwise it 
> almost defeats the merit of converting vdpa_dev_mutex to the same. 
> This change would benefit multiple parallel readers. 
It looks like the lately posted v6 series missed this change somehow?

-Siwei