Re: [PATCH 3/5] drm/xe: Take a reference to xe file when user creates exec_queue

[Matthew Brost <matthew.brost@intel.com>]

On Mon, Jul 08, 2024 at 01:21:01PM -0700, Umesh Nerlige Ramappa wrote:
> Take a reference to xe file object when user creates an exec queue so
> that the xe file object is available for the lifetime of the queue.
> 
> Signed-off-by: Umesh Nerlige Ramappa <umesh.nerlige.ramappa@intel.com>
> ---
>  drivers/gpu/drm/xe/xe_exec_queue.c       | 6 ++++++
>  drivers/gpu/drm/xe/xe_exec_queue_types.h | 3 +++
>  2 files changed, 9 insertions(+)
> 
> diff --git a/drivers/gpu/drm/xe/xe_exec_queue.c b/drivers/gpu/drm/xe/xe_exec_queue.c
> index 0ba37835849b..b01eccdd75ba 100644
> --- a/drivers/gpu/drm/xe/xe_exec_queue.c
> +++ b/drivers/gpu/drm/xe/xe_exec_queue.c
> @@ -37,6 +37,10 @@ static void __xe_exec_queue_free(struct xe_exec_queue *q)
>  {
>  	if (q->vm)
>  		xe_vm_put(q->vm);
> +
> +	if (q->xef)
> +		xe_file_put(q->xef);
> +
>  	kfree(q);
>  }
>  
> @@ -640,6 +644,8 @@ int xe_exec_queue_create_ioctl(struct drm_device *dev, void *data,
>  			if (XE_IOCTL_DBG(xe, err))
>  				goto put_exec_queue;
>  		}
> +
> +		q->xef = xe_file_get(xef);

This doesn't look like the right place. All exec queues include VM bind
ones should have a ref.

With that, the right place seems to be right before or after args->exec_queue_id = id;

Matt

>  	}
>  
>  	mutex_lock(&xef->exec_queue.lock);
> diff --git a/drivers/gpu/drm/xe/xe_exec_queue_types.h b/drivers/gpu/drm/xe/xe_exec_queue_types.h
> index ded9f9396429..f768e48f31e4 100644
> --- a/drivers/gpu/drm/xe/xe_exec_queue_types.h
> +++ b/drivers/gpu/drm/xe/xe_exec_queue_types.h
> @@ -38,6 +38,9 @@ enum xe_exec_queue_priority {
>   * a kernel object.
>   */
>  struct xe_exec_queue {
> +	/** @xef: Back pointer to xe file is this is user created exec queue */
> +	struct xe_file *xef;
> +
>  	/** @gt: graphics tile this exec queue can submit to */
>  	struct xe_gt *gt;
>  	/**
> -- 
> 2.38.1
>