Re: [PATCH 4/5] drm/i915: Use __sg_alloc_table_from_pages for allocating object backing store

Chris Wilson
2016-10-21T14:27:57Z

On Fri, Oct 21, 2016 at 03:11:22PM +0100, Tvrtko Ursulin wrote:
> @@ -2236,18 +2233,16 @@ i915_gem_object_get_pages_gtt(struct drm_i915_gem_object *obj)
> BUG_ON(obj->base.read_domains & I915_GEM_GPU_DOMAINS);
> BUG_ON(obj->base.write_domain & I915_GEM_GPU_DOMAINS);
>
> - max_segment = swiotlb_max_size();
> - if (!max_segment)
> - max_segment = rounddown(UINT_MAX, PAGE_SIZE);
> -
> - st = kmalloc(sizeof(*st), GFP_KERNEL);
> - if (st == NULL)
> - return -ENOMEM;
> -
> page_count = obj->base.size / PAGE_SIZE;
> - if (sg_alloc_table(st, page_count, GFP_KERNEL)) {
> - kfree(st);
> + pages = drm_malloc_gfp(page_count, sizeof(struct page *),
> + GFP_TEMPORARY | __GFP_ZERO);
> + if (!pages)
> return -ENOMEM;

Full circle! The whole reason this exists was to avoid that vmalloc. I
don't really want it back...
-Chris

--
Chris Wilson, Intel Open Source Technology Centre