Re: [PATCH v2 1/2] drm/panthor: Add PANTHOR_GROUP_PRIORITY_REALTIME group priority

[Boris Brezillon <boris.brezillon@collabora.com>]

On Thu,  5 Sep 2024 19:32:22 +0200
Mary Guillemard <mary.guillemard@collabora.com> wrote:

> This adds a new value to drm_panthor_group_priority exposing the
> realtime priority to userspace.
> 
> This is required to implement NV_context_priority_realtime in Mesa.
> 
> v2:
> - Add Steven Price r-b
> 
> Signed-off-by: Mary Guillemard <mary.guillemard@collabora.com>
> Reviewed-by: Steven Price <steven.price@arm.com>

Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>

> ---
>  drivers/gpu/drm/panthor/panthor_drv.c   | 2 +-
>  drivers/gpu/drm/panthor/panthor_sched.c | 2 --
>  include/uapi/drm/panthor_drm.h          | 7 +++++++
>  3 files changed, 8 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/gpu/drm/panthor/panthor_drv.c b/drivers/gpu/drm/panthor/panthor_drv.c
> index 0caf9e9a8c45..7b1db2adcb4c 100644
> --- a/drivers/gpu/drm/panthor/panthor_drv.c
> +++ b/drivers/gpu/drm/panthor/panthor_drv.c
> @@ -1041,7 +1041,7 @@ static int group_priority_permit(struct drm_file *file,
>  				 u8 priority)
>  {
>  	/* Ensure that priority is valid */
> -	if (priority > PANTHOR_GROUP_PRIORITY_HIGH)
> +	if (priority > PANTHOR_GROUP_PRIORITY_REALTIME)
>  		return -EINVAL;
>  
>  	/* Medium priority and below are always allowed */
> diff --git a/drivers/gpu/drm/panthor/panthor_sched.c b/drivers/gpu/drm/panthor/panthor_sched.c
> index 91a31b70c037..86908ada7335 100644
> --- a/drivers/gpu/drm/panthor/panthor_sched.c
> +++ b/drivers/gpu/drm/panthor/panthor_sched.c
> @@ -137,8 +137,6 @@ enum panthor_csg_priority {
>  	 * non-real-time groups. When such a group becomes executable,
>  	 * it will evict the group with the lowest non-rt priority if
>  	 * there's no free group slot available.
> -	 *
> -	 * Currently not exposed to userspace.
>  	 */
>  	PANTHOR_CSG_PRIORITY_RT,
>  
> diff --git a/include/uapi/drm/panthor_drm.h b/include/uapi/drm/panthor_drm.h
> index 1fd8473548ac..011a555e4674 100644
> --- a/include/uapi/drm/panthor_drm.h
> +++ b/include/uapi/drm/panthor_drm.h
> @@ -720,6 +720,13 @@ enum drm_panthor_group_priority {
>  	 * Requires CAP_SYS_NICE or DRM_MASTER.
>  	 */
>  	PANTHOR_GROUP_PRIORITY_HIGH,
> +
> +	/**
> +	 * @PANTHOR_GROUP_PRIORITY_REALTIME: Realtime priority group.
> +	 *
> +	 * Requires CAP_SYS_NICE or DRM_MASTER.
> +	 */
> +	PANTHOR_GROUP_PRIORITY_REALTIME,
>  };
>  
>  /**