Commit dd03daec authored by Christian König's avatar Christian König Committed by Alex Deucher
Browse files

drm/amdgpu: restructure amdgpu_vram_mgr_new 



Merge the two loops, loosen the restriction for big allocations.
This reduces the CPU overhead in the good case, but increases
it a bit under memory pressure.

Signed-off-by: default avatarChristian König <christian.koenig@amd.com>
Acked-and-Tested-by: default avatarNirmoy Das <nirmoy.das@amd.com>
Reviewed-by: default avatarFelix Kuehling <Felix.Kuehling@amd.com>
Signed-off-by: default avatarAlex Deucher <alexander.deucher@amd.com>
parent c0f76fc8

drivers/gpu/drm/amd/amdgpu/amdgpu_vram_mgr.c

+27 −31
Original line number Diff line number Diff line
@@ -358,13 +358,13 @@ static int amdgpu_vram_mgr_new(struct ttm_resource_manager *man, 
			       const struct ttm_place *place,

			       struct ttm_resource *mem)

{

	unsigned long lpfn, num_nodes, pages_per_node, pages_left, pages;

	struct amdgpu_vram_mgr *mgr = to_vram_mgr(man);

	struct amdgpu_device *adev = to_amdgpu_device(mgr);

	uint64_t vis_usage = 0, mem_bytes, max_bytes;

	struct drm_mm *mm = &mgr->mm;

	struct drm_mm_node *nodes;

	enum drm_mm_insert_mode mode;

	unsigned long lpfn, num_nodes, pages_per_node, pages_left;

	uint64_t vis_usage = 0, mem_bytes, max_bytes;

	struct drm_mm_node *nodes;

	unsigned i;

	int r;
@@ -391,9 +391,10 @@ static int amdgpu_vram_mgr_new(struct ttm_resource_manager *man, 
		pages_per_node = HPAGE_PMD_NR;

#else

		/* default to 2MB */

		pages_per_node = (2UL << (20UL - PAGE_SHIFT));

		pages_per_node = 2UL << (20UL - PAGE_SHIFT);

#endif

		pages_per_node = max((uint32_t)pages_per_node, mem->page_alignment);

		pages_per_node = max_t(uint32_t, pages_per_node,

				       mem->page_alignment);

		num_nodes = DIV_ROUND_UP(mem->num_pages, pages_per_node);

	}
@@ -411,42 +412,37 @@ static int amdgpu_vram_mgr_new(struct ttm_resource_manager *man, 
	mem->start = 0;

	pages_left = mem->num_pages;



	spin_lock(&mgr->lock);

	for (i = 0; pages_left >= pages_per_node; ++i) {

		unsigned long pages = rounddown_pow_of_two(pages_left);



	/* Limit maximum size to 2GB due to SG table limitations */

		pages = min(pages, (2UL << (30 - PAGE_SHIFT)));



		r = drm_mm_insert_node_in_range(mm, &nodes[i], pages,

						pages_per_node, 0,

						place->fpfn, lpfn,

						mode);

		if (unlikely(r))

			break;



		vis_usage += amdgpu_vram_mgr_vis_size(adev, &nodes[i]);

		amdgpu_vram_mgr_virt_start(mem, &nodes[i]);

		pages_left -= pages;

	}

	pages = min(pages_left, 2UL << (30 - PAGE_SHIFT));



	for (; pages_left; ++i) {

		unsigned long pages = min(pages_left, pages_per_node);

	i = 0;

	spin_lock(&mgr->lock);

	while (pages_left) {

		uint32_t alignment = mem->page_alignment;



		if (pages == pages_per_node)

		if (pages >= pages_per_node)

			alignment = pages_per_node;



		r = drm_mm_insert_node_in_range(mm, &nodes[i],

						pages, alignment, 0,

						place->fpfn, lpfn,

						mode);

		if (unlikely(r))

		r = drm_mm_insert_node_in_range(mm, &nodes[i], pages, alignment,

						0, place->fpfn, lpfn, mode);

		if (unlikely(r)) {

			if (pages > pages_per_node) {

				if (is_power_of_2(pages))

					pages = pages / 2;

				else

					pages = rounddown_pow_of_two(pages);

				continue;

			}

			goto error;

		}



		vis_usage += amdgpu_vram_mgr_vis_size(adev, &nodes[i]);

		amdgpu_vram_mgr_virt_start(mem, &nodes[i]);

		pages_left -= pages;

		++i;



		if (pages > pages_left)

			pages = pages_left;

	}

	spin_unlock(&mgr->lock);