[Intel-gfx] [PATCH 1/2] drm/i915: Extract checking for backing struct pages to a helper

[Tvrtko Ursulin]

On 20/06/16 10:31, Chris Wilson wrote:
> Currently to see if an object is backed by struct pages (as opposed to
> being a simple pointer to stolen memory, for example) we do a manual
> check on the obj->ops->flags. This is quite shouty and before adding
> more checks in future, we should make it a bit calmer.
>
> Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
> ---
>   drivers/gpu/drm/i915/i915_drv.h | 6 ++++++
>   drivers/gpu/drm/i915/i915_gem.c | 4 ++--
>   2 files changed, 8 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
> index 25ebe4660764..48928227bdcc 100644
> --- a/drivers/gpu/drm/i915/i915_drv.h
> +++ b/drivers/gpu/drm/i915/i915_drv.h
> @@ -2266,6 +2266,12 @@ struct drm_i915_gem_object {
>   };
>   #define to_intel_bo(x) container_of(x, struct drm_i915_gem_object, base)
>
> +static inline bool
> +i915_gem_object_has_struct_page(const struct drm_i915_gem_object *obj)
> +{
> +	return obj->ops->flags & I915_GEM_OBJECT_HAS_STRUCT_PAGE;
> +}
> +
>   /*
>    * Optimised SGL iterator for GEM objects
>    */
> diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
> index 21d0dea57312..7f6879cc82fb 100644
> --- a/drivers/gpu/drm/i915/i915_gem.c
> +++ b/drivers/gpu/drm/i915/i915_gem.c
> @@ -508,7 +508,7 @@ int i915_gem_obj_prepare_shmem_read(struct drm_i915_gem_object *obj,
>
>   	*needs_clflush = 0;
>
> -	if (WARN_ON((obj->ops->flags & I915_GEM_OBJECT_HAS_STRUCT_PAGE) == 0))
> +	if (WARN_ON(!i915_gem_object_has_struct_page(obj)))
>   		return -EINVAL;
>
>   	if (!(obj->base.read_domains & I915_GEM_DOMAIN_CPU)) {
> @@ -5528,7 +5528,7 @@ i915_gem_object_get_dirty_page(struct drm_i915_gem_object *obj, int n)
>   	struct page *page;
>
>   	/* Only default objects have per-page dirty tracking */
> -	if (WARN_ON((obj->ops->flags & I915_GEM_OBJECT_HAS_STRUCT_PAGE) == 0))
> +	if (WARN_ON(!i915_gem_object_has_struct_page(obj)))
>   		return NULL;
>
>   	page = i915_gem_object_get_page(obj, n);
>

Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin at intel.com>

Regards,

Tvrtko