Re: [PATCH 05/20] drm/xe/ggtt: use drm_dev_enter to mark device section

[Andrzej Hajda <andrzej.hajda@intel.com>]

On 10.05.2024 20:12, Matthew Auld wrote:
> Device can be hotunplugged before we start destroying gem objects. In
> such a case don't touch the GGTT entries, trigger any invalidations or
> mess around with rpm.  This should already be taken care of when
> removing the device, we just need to take care of dealing with the
> software state, like removing the mm node.
> 
> v2: (Andrzej)
>    - Avoid some duplication by tracking the bound status and checking
>      that instead.
> 
> References: https://gitlab.freedesktop.org/drm/xe/kernel/-/issues/1717
> Signed-off-by: Matthew Auld <matthew.auld@intel.com>
> Cc: Andrzej Hajda <andrzej.hajda@intel.com>
> Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>

Reviewed-by: Andrzej Hajda <andrzej.hajda@intel.com>

Regards
Andrzej

> ---
>   drivers/gpu/drm/xe/xe_ggtt.c | 18 +++++++++++++++---
>   1 file changed, 15 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/gpu/drm/xe/xe_ggtt.c b/drivers/gpu/drm/xe/xe_ggtt.c
> index 0d541f55b4fc..17e5066763db 100644
> --- a/drivers/gpu/drm/xe/xe_ggtt.c
> +++ b/drivers/gpu/drm/xe/xe_ggtt.c
> @@ -8,6 +8,7 @@
>   #include <linux/io-64-nonatomic-lo-hi.h>
>   #include <linux/sizes.h>
>   
> +#include <drm/drm_drv.h>
>   #include <drm/drm_managed.h>
>   #include <drm/i915_drm.h>
>   
> @@ -433,18 +434,29 @@ int xe_ggtt_insert_bo(struct xe_ggtt *ggtt, struct xe_bo *bo)
>   void xe_ggtt_remove_node(struct xe_ggtt *ggtt, struct drm_mm_node *node,
>   			 bool invalidate)
>   {
> -	xe_pm_runtime_get_noresume(tile_to_xe(ggtt->tile));
> +	struct xe_device *xe = tile_to_xe(ggtt->tile);
> +	bool bound;
> +	int idx;
> +
> +	bound = drm_dev_enter(&xe->drm, &idx);
> +	if (bound)
> +		xe_pm_runtime_get_noresume(xe);
>   
>   	mutex_lock(&ggtt->lock);
> -	xe_ggtt_clear(ggtt, node->start, node->size);
> +	if (bound)
> +		xe_ggtt_clear(ggtt, node->start, node->size);
>   	drm_mm_remove_node(node);
>   	node->size = 0;
>   	mutex_unlock(&ggtt->lock);
>   
> +	if (!bound)
> +		return;
> +
>   	if (invalidate)
>   		xe_ggtt_invalidate(ggtt);
>   
> -	xe_pm_runtime_put(tile_to_xe(ggtt->tile));
> +	xe_pm_runtime_put(xe);
> +	drm_dev_exit(idx);
>   }
>   
>   void xe_ggtt_remove_bo(struct xe_ggtt *ggtt, struct xe_bo *bo)