Re: [PATCH v5 03/19] drm/atomic: Drop drm_private_obj.state assignment from create_state

[Thomas Zimmermann <tzimmermann@suse.de>]

Am 19.05.26 um 11:01 schrieb Maxime Ripard:
> The initial intent of the atomic_create_state hook was to simply
> allocate a proper drm_private_state and return it, without any side
> effect.
>
> However, __drm_atomic_helper_private_obj_create_state(), which most
> atomic_create_state implementations call, introduces a side effect by
> setting drm_private_obj.state to the newly allocated state.
>
> This assignment defeats the purpose, but is also redundant since
> drm_atomic_private_obj_init(), the only call site for the
> atomic_create_state hook, will also set this pointer to the newly
> allocated state.
>
> Drop the assignment in __drm_atomic_helper_private_obj_create_state().
>
> Fixes: e7be39ed1716 ("drm/atomic-helper: Add private_obj atomic_create_state helper")
> Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
> Signed-off-by: Maxime Ripard <mripard@kernel.org>

Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>

> ---
>   drivers/gpu/drm/drm_atomic_state_helper.c | 2 --
>   1 file changed, 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/drm_atomic_state_helper.c b/drivers/gpu/drm/drm_atomic_state_helper.c
> index cc70508d4fdb..a82568d87e4f 100644
> --- a/drivers/gpu/drm/drm_atomic_state_helper.c
> +++ b/drivers/gpu/drm/drm_atomic_state_helper.c
> @@ -729,12 +729,10 @@ EXPORT_SYMBOL(drm_atomic_helper_connector_destroy_state);
>   void __drm_atomic_helper_private_obj_create_state(struct drm_private_obj *obj,
>   						  struct drm_private_state *state)
>   {
>   	if (state)
>   		state->obj = obj;
> -
> -	obj->state = state;
>   }
>   EXPORT_SYMBOL(__drm_atomic_helper_private_obj_create_state);
>   
>   /**
>    * __drm_atomic_helper_private_obj_duplicate_state - copy atomic private state
>

-- 
--
Thomas Zimmermann
Graphics Driver Developer
SUSE Software Solutions Germany GmbH
Frankenstr. 146, 90461 Nürnberg, Germany, www.suse.com
GF: Jochen Jaser, Andrew McDonald, Werner Knoblich, (HRB 36809, AG Nürnberg)