Re: [PATCH v8 08/10] drm/xe: Improve wedged state management

[Rodrigo Vivi <rodrigo.vivi@intel.com>]

On Wed, Jun 03, 2026 at 03:47:08PM +0530, Raag Jadav wrote:
> Currently, wedged state is serving a single usecase where the device is
> declared wedged, but this doesn't allow any wedged state management for
> runtime usecases. In preparation of usecases which requires to facilitate
> temporary device wedging, convert wedged.flag to wedged.ref which serves
> as a driver internal refcount and blocks critical path execution during
> device lifetime and while at it, introduce wedged.fini and use it as a
> cleanup indicator during driver unwind which operates independent of the
> refcount.
> 
> Signed-off-by: Raag Jadav <raag.jadav@intel.com>
> ---
>  drivers/gpu/drm/xe/xe_device.c       |  5 +++--
>  drivers/gpu/drm/xe/xe_device.h       | 12 +++++++++++-
>  drivers/gpu/drm/xe/xe_device_types.h |  6 ++++--
>  3 files changed, 18 insertions(+), 5 deletions(-)
> 
> diff --git a/drivers/gpu/drm/xe/xe_device.c b/drivers/gpu/drm/xe/xe_device.c
> index 9e0cbad8adb0..d77f8f054a1a 100644
> --- a/drivers/gpu/drm/xe/xe_device.c
> +++ b/drivers/gpu/drm/xe/xe_device.c
> @@ -917,7 +917,7 @@ static void xe_device_wedged_fini(struct drm_device *drm, void *arg)
>  {
>  	struct xe_device *xe = arg;
>  
> -	if (atomic_read(&xe->wedged.flag))
> +	if (atomic_read(&xe->wedged.fini))
>  		xe_pm_runtime_put(xe);
>  }
>  
> @@ -1413,7 +1413,8 @@ void xe_device_declare_wedged(struct xe_device *xe)
>  		return;
>  	}
>  
> -	if (!atomic_xchg(&xe->wedged.flag, 1)) {
> +	if (!atomic_xchg(&xe->wedged.fini, 1)) {
> +		xe_device_wedged_get(xe);
>  		xe->needs_flr_on_fini = true;
>  		xe_pm_runtime_get_noresume(xe);
>  		drm_err(&xe->drm,
> diff --git a/drivers/gpu/drm/xe/xe_device.h b/drivers/gpu/drm/xe/xe_device.h
> index d61fdb362f91..14677729aa24 100644
> --- a/drivers/gpu/drm/xe/xe_device.h
> +++ b/drivers/gpu/drm/xe/xe_device.h
> @@ -194,9 +194,19 @@ bool xe_device_is_l2_flush_optimized(struct xe_device *xe);
>  void xe_device_td_flush(struct xe_device *xe);
>  void xe_device_l2_flush(struct xe_device *xe);
>  
> +static inline void xe_device_wedged_get(struct xe_device *xe)
> +{
> +	atomic_inc(&xe->wedged.ref);
> +}
> +
> +static inline void xe_device_wedged_put(struct xe_device *xe)
> +{
> +	atomic_dec(&xe->wedged.ref);
> +}
> +
>  static inline bool xe_device_wedged(struct xe_device *xe)
>  {
> -	return atomic_read(&xe->wedged.flag);
> +	return atomic_read(&xe->wedged.ref);
>  }
>  
>  void xe_device_set_wedged_method(struct xe_device *xe, unsigned long method);
> diff --git a/drivers/gpu/drm/xe/xe_device_types.h b/drivers/gpu/drm/xe/xe_device_types.h
> index 32dd2ffbc796..66e673e4e3e7 100644
> --- a/drivers/gpu/drm/xe/xe_device_types.h
> +++ b/drivers/gpu/drm/xe/xe_device_types.h
> @@ -485,8 +485,10 @@ struct xe_device {
>  
>  	/** @wedged: Struct to control Wedged States and mode */
>  	struct {
> -		/** @wedged.flag: Xe device faced a critical error and is now blocked. */
> -		atomic_t flag;
> +		/** @wedged.fini: Needs cleanup on fini */
> +		atomic_t fini;

to me it is easier to see this as a 'permanent' flag than
a flag to 'clean' on 'fini'.

but up to you...

either way:

Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>

> +		/** @wedged.ref: Refcount for wedged device, blocks critical path execution */
> +		atomic_t ref;
>  		/** @wedged.mode: Mode controlled by kernel parameter and debugfs */
>  		enum xe_wedged_mode mode;
>  		/** @wedged.method: Recovery method to be sent in the drm device wedged uevent */
> -- 
> 2.43.0
>