Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 86aeaa09 authored by Thomas Hellstrom's avatar Thomas Hellstrom
Browse files

drm/vmwgfx: Use an RBtree instead of linked list for MOB resources 



With emulated coherent memory we need to be able to quickly look up
a resource from the MOB offset. Instead of traversing a linked list with
O(n) worst case, use an RBtree with O(log n) worst case complexity.

Signed-off-by: default avatarThomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: default avatarDeepak Rawat <drawat@vmware.com>
parent 93392217

drivers/gpu/drm/vmwgfx/vmwgfx_bo.c

+3 −2
Original line number Diff line number Diff line
@@ -464,6 +464,7 @@ void vmw_bo_bo_free(struct ttm_buffer_object *bo) 
	struct vmw_buffer_object *vmw_bo = vmw_buffer_object(bo);



	WARN_ON(vmw_bo->dirty);

	WARN_ON(!RB_EMPTY_ROOT(&vmw_bo->res_tree));

	vmw_bo_unmap(vmw_bo);

	kfree(vmw_bo);

}
@@ -480,6 +481,7 @@ static void vmw_user_bo_destroy(struct ttm_buffer_object *bo) 
	struct vmw_buffer_object *vbo = &vmw_user_bo->vbo;



	WARN_ON(vbo->dirty);

	WARN_ON(!RB_EMPTY_ROOT(&vbo->res_tree));

	vmw_bo_unmap(vbo);

	ttm_prime_object_kfree(vmw_user_bo, prime);

}
@@ -515,8 +517,7 @@ int vmw_bo_init(struct vmw_private *dev_priv, 
	memset(vmw_bo, 0, sizeof(*vmw_bo));

	BUILD_BUG_ON(TTM_MAX_BO_PRIORITY <= 3);

	vmw_bo->base.priority = 3;



	INIT_LIST_HEAD(&vmw_bo->res_list);

	vmw_bo->res_tree = RB_ROOT;



	ret = ttm_bo_init(bdev, &vmw_bo->base, size,

			  ttm_bo_type_device, placement,

drivers/gpu/drm/vmwgfx/vmwgfx_drv.h

+5 −5
Original line number Diff line number Diff line
@@ -89,7 +89,7 @@ struct vmw_fpriv { 
/**

 * struct vmw_buffer_object - TTM buffer object with vmwgfx additions

 * @base: The TTM buffer object

 * @res_list: List of resources using this buffer object as a backing MOB

 * @res_tree: RB tree of resources using this buffer object as a backing MOB

 * @pin_count: pin depth

 * @dx_query_ctx: DX context if this buffer object is used as a DX query MOB

 * @map: Kmap object for semi-persistent mappings
@@ -98,7 +98,7 @@ struct vmw_fpriv { 
 */

struct vmw_buffer_object {

	struct ttm_buffer_object base;

	struct list_head res_list;

	struct rb_root res_tree;

	s32 pin_count;

	/* Not ref-counted.  Protected by binding_mutex */

	struct vmw_resource *dx_query_ctx;
@@ -146,8 +146,8 @@ struct vmw_res_func; 
 * pin-count greater than zero. It is not on the resource LRU lists and its

 * backup buffer is pinned. Hence it can't be evicted.

 * @func: Method vtable for this resource. Immutable.

 * @mob_node; Node for the MOB backup rbtree. Protected by @backup reserved.

 * @lru_head: List head for the LRU list. Protected by @dev_priv::resource_lock.

 * @mob_head: List head for the MOB backup list. Protected by @backup reserved.

 * @binding_head: List head for the context binding list. Protected by

 * the @dev_priv::binding_mutex

 * @res_free: The resource destructor.
@@ -168,8 +168,8 @@ struct vmw_resource { 
	unsigned long backup_offset;

	unsigned long pin_count;

	const struct vmw_res_func *func;

	struct rb_node mob_node;

	struct list_head lru_head;

	struct list_head mob_head;

	struct list_head binding_head;

	struct vmw_resource_dirty *dirty;

	void (*res_free) (struct vmw_resource *res);
@@ -742,7 +742,7 @@ void vmw_resource_dirty_update(struct vmw_resource *res, pgoff_t start, 
 */

static inline bool vmw_resource_mob_attached(const struct vmw_resource *res)

{

	return !list_empty(&res->mob_head);

	return !RB_EMPTY_NODE(&res->mob_node);

}



/**

drivers/gpu/drm/vmwgfx/vmwgfx_resource.c

+24 −9
Original line number Diff line number Diff line
@@ -41,11 +41,24 @@ 
void vmw_resource_mob_attach(struct vmw_resource *res)

{

	struct vmw_buffer_object *backup = res->backup;

	struct rb_node **new = &backup->res_tree.rb_node, *parent = NULL;



	lockdep_assert_held(&backup->base.resv->lock.base);

	res->used_prio = (res->res_dirty) ? res->func->dirty_prio :

		res->func->prio;

	list_add_tail(&res->mob_head, &backup->res_list);



	while (*new) {

		struct vmw_resource *this =

			container_of(*new, struct vmw_resource, mob_node);



		parent = *new;

		new = (res->backup_offset < this->backup_offset) ?

			&((*new)->rb_left) : &((*new)->rb_right);

	}



	rb_link_node(&res->mob_node, parent, new);

	rb_insert_color(&res->mob_node, &backup->res_tree);



	vmw_bo_prio_add(backup, res->used_prio);

}
@@ -59,7 +72,8 @@ void vmw_resource_mob_detach(struct vmw_resource *res) 


	lockdep_assert_held(&backup->base.resv->lock.base);

	if (vmw_resource_mob_attached(res)) {

		list_del_init(&res->mob_head);

		rb_erase(&res->mob_node, &backup->res_tree);

		RB_CLEAR_NODE(&res->mob_node);

		vmw_bo_prio_del(backup, res->used_prio);

	}

}
@@ -206,8 +220,8 @@ int vmw_resource_init(struct vmw_private *dev_priv, struct vmw_resource *res, 
	res->res_free = res_free;

	res->dev_priv = dev_priv;

	res->func = func;

	RB_CLEAR_NODE(&res->mob_node);

	INIT_LIST_HEAD(&res->lru_head);

	INIT_LIST_HEAD(&res->mob_head);

	INIT_LIST_HEAD(&res->binding_head);

	res->id = -1;

	res->backup = NULL;
@@ -756,19 +770,20 @@ int vmw_resource_validate(struct vmw_resource *res, bool intr) 
 */

void vmw_resource_unbind_list(struct vmw_buffer_object *vbo)

{



	struct vmw_resource *res, *next;

	struct ttm_validate_buffer val_buf = {

		.bo = &vbo->base,

		.num_shared = 0

	};



	lockdep_assert_held(&vbo->base.resv->lock.base);

	list_for_each_entry_safe(res, next, &vbo->res_list, mob_head) {

		if (!res->func->unbind)

			continue;

	while (!RB_EMPTY_ROOT(&vbo->res_tree)) {

		struct rb_node *node = vbo->res_tree.rb_node;

		struct vmw_resource *res =

			container_of(node, struct vmw_resource, mob_node);



		if (!WARN_ON_ONCE(!res->func->unbind))

			(void) res->func->unbind(res, res->res_dirty, &val_buf);



		res->backup_dirty = true;

		res->res_dirty = false;

		vmw_resource_mob_detach(res);