Re: [PATCH v2 6/8] vdpa_sim: use kthread worker

[Jason Wang]

On Thu, Mar 2, 2023 at 7:35 PM Stefano Garzarella <sgarzare@xxxxxxxxxx> wrote:
>
> Let's use our own kthread to run device jobs.
> This allows us more flexibility, especially we can attach the kthread
> to the user address space when vDPA uses user's VA.
>
> Signed-off-by: Stefano Garzarella <sgarzare@xxxxxxxxxx>

Acked-by: Jason Wang <jasowang@xxxxxxxxxx>

Thanks



> ---
>  drivers/vdpa/vdpa_sim/vdpa_sim.h |  3 ++-
>  drivers/vdpa/vdpa_sim/vdpa_sim.c | 17 ++++++++++++-----
>  2 files changed, 14 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/vdpa/vdpa_sim/vdpa_sim.h b/drivers/vdpa/vdpa_sim/vdpa_sim.h
> index acee20faaf6a..ce83f9130a5d 100644
> --- a/drivers/vdpa/vdpa_sim/vdpa_sim.h
> +++ b/drivers/vdpa/vdpa_sim/vdpa_sim.h
> @@ -57,7 +57,8 @@ struct vdpasim_dev_attr {
>  struct vdpasim {
>         struct vdpa_device vdpa;
>         struct vdpasim_virtqueue *vqs;
> -       struct work_struct work;
> +       struct kthread_worker *worker;
> +       struct kthread_work work;
>         struct vdpasim_dev_attr dev_attr;
>         /* spinlock to synchronize virtqueue state */
>         spinlock_t lock;
> diff --git a/drivers/vdpa/vdpa_sim/vdpa_sim.c b/drivers/vdpa/vdpa_sim/vdpa_sim.c
> index a6ee830efc38..6feb29726c2a 100644
> --- a/drivers/vdpa/vdpa_sim/vdpa_sim.c
> +++ b/drivers/vdpa/vdpa_sim/vdpa_sim.c
> @@ -11,8 +11,8 @@
>  #include <linux/module.h>
>  #include <linux/device.h>
>  #include <linux/kernel.h>
> +#include <linux/kthread.h>
>  #include <linux/slab.h>
> -#include <linux/sched.h>
>  #include <linux/dma-map-ops.h>
>  #include <linux/vringh.h>
>  #include <linux/vdpa.h>
> @@ -116,7 +116,7 @@ static void vdpasim_do_reset(struct vdpasim *vdpasim)
>  static const struct vdpa_config_ops vdpasim_config_ops;
>  static const struct vdpa_config_ops vdpasim_batch_config_ops;
>
> -static void vdpasim_work_fn(struct work_struct *work)
> +static void vdpasim_work_fn(struct kthread_work *work)
>  {
>         struct vdpasim *vdpasim = container_of(work, struct vdpasim, work);
>
> @@ -159,7 +159,13 @@ struct vdpasim *vdpasim_create(struct vdpasim_dev_attr *dev_attr,
>
>         vdpasim = vdpa_to_sim(vdpa);
>         vdpasim->dev_attr = *dev_attr;
> -       INIT_WORK(&vdpasim->work, vdpasim_work_fn);
> +
> +       kthread_init_work(&vdpasim->work, vdpasim_work_fn);
> +       vdpasim->worker = kthread_create_worker(0, "vDPA sim worker: %s",
> +                                               dev_attr->name);
> +       if (IS_ERR(vdpasim->worker))
> +               goto err_iommu;
> +
>         spin_lock_init(&vdpasim->lock);
>         spin_lock_init(&vdpasim->iommu_lock);
>
> @@ -212,7 +218,7 @@ EXPORT_SYMBOL_GPL(vdpasim_create);
>
>  void vdpasim_schedule_work(struct vdpasim *vdpasim)
>  {
> -       schedule_work(&vdpasim->work);
> +       kthread_queue_work(vdpasim->worker, &vdpasim->work);
>  }
>  EXPORT_SYMBOL_GPL(vdpasim_schedule_work);
>
> @@ -612,7 +618,8 @@ static void vdpasim_free(struct vdpa_device *vdpa)
>         struct vdpasim *vdpasim = vdpa_to_sim(vdpa);
>         int i;
>
> -       cancel_work_sync(&vdpasim->work);
> +       kthread_cancel_work_sync(&vdpasim->work);
> +       kthread_destroy_worker(vdpasim->worker);
>
>         for (i = 0; i < vdpasim->dev_attr.nvqs; i++) {
>                 vringh_kiov_cleanup(&vdpasim->vqs[i].out_iov);
> --
> 2.39.2
>