Commit 271e7dec authored by Christian König's avatar Christian König
Browse files

drm/mm: optimize find_hole() as well 



Abort early if there isn't enough space to allocate from a subtree.

Signed-off-by: default avatarChristian König <christian.koenig@amd.com>
Acked-by: default avatarNirmoy Das <nirmoy.das@amd.com>
Link: https://patchwork.freedesktop.org/patch/370297/
parent 41c0e78a

drivers/gpu/drm/drm_mm.c

+7 −4
Original line number Diff line number Diff line
@@ -325,7 +325,7 @@ static struct drm_mm_node *best_hole(struct drm_mm *mm, u64 size) 
	return best;

}



static struct drm_mm_node *find_hole(struct drm_mm *mm, u64 addr)

static struct drm_mm_node *find_hole_addr(struct drm_mm *mm, u64 addr, u64 size)

{

	struct rb_node *rb = mm->holes_addr.rb_node;

	struct drm_mm_node *node = NULL;
@@ -333,6 +333,9 @@ static struct drm_mm_node *find_hole(struct drm_mm *mm, u64 addr) 
	while (rb) {

		u64 hole_start;



		if (rb_hole_addr_to_node(rb)->subtree_max_hole < size)

			break;



		node = rb_hole_addr_to_node(rb);

		hole_start = __drm_mm_hole_node_start(node);
@@ -358,10 +361,10 @@ first_hole(struct drm_mm *mm, 
		return best_hole(mm, size);



	case DRM_MM_INSERT_LOW:

		return find_hole(mm, start);

		return find_hole_addr(mm, start, size);



	case DRM_MM_INSERT_HIGH:

		return find_hole(mm, end);

		return find_hole_addr(mm, end, size);



	case DRM_MM_INSERT_EVICT:

		return list_first_entry_or_null(&mm->hole_stack,
@@ -497,7 +500,7 @@ int drm_mm_reserve_node(struct drm_mm *mm, struct drm_mm_node *node) 
		return -ENOSPC;



	/* Find the relevant hole to add our node to */

	hole = find_hole(mm, node->start);

	hole = find_hole_addr(mm, node->start, 0);

	if (!hole)

		return -ENOSPC;

drivers/gpu/drm/selftests/test-drm_mm.c

+0 −11
Original line number Diff line number Diff line
@@ -1981,16 +1981,6 @@ static int __igt_once(unsigned int mode) 
	}



	memset(&node, 0, sizeof(node));

	err = drm_mm_insert_node_generic(&mm, &node,

					 2, 0, 0,

					 mode | DRM_MM_INSERT_ONCE);

	if (!err) {

		pr_err("Unexpectedly inserted the node into the wrong hole: node.start=%llx\n",

		       node.start);

		err = -EINVAL;

		goto err_node;

	}



	err = drm_mm_insert_node_generic(&mm, &node, 2, 0, 0, mode);

	if (err) {

		pr_err("Could not insert the node into the available hole!\n");
@@ -1998,7 +1988,6 @@ static int __igt_once(unsigned int mode) 
		goto err_hi;

	}



err_node:

	drm_mm_remove_node(&node);

err_hi:

	drm_mm_remove_node(&rsvd_hi);