From: Thomas Hellstrom thellstrom@vmware.com
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.
Cc: Andrew Morton akpm@linux-foundation.org Cc: Matthew Wilcox willy@infradead.org Cc: Will Deacon will.deacon@arm.com Cc: Peter Zijlstra peterz@infradead.org Cc: Rik van Riel riel@surriel.com Cc: Minchan Kim minchan@kernel.org Cc: Michal Hocko mhocko@suse.com Cc: Huang Ying ying.huang@intel.com Cc: Souptick Joarder jrdr.linux@gmail.com Cc: "Jérôme Glisse" jglisse@redhat.com Cc: "Christian König" christian.koenig@amd.com Cc: Christoph Hellwig hch@infradead.org Signed-off-by: Thomas Hellstrom thellstrom@vmware.com Reviewed-by: Deepak Rawat drawat@vmware.com --- drivers/gpu/drm/vmwgfx/vmwgfx_bo.c | 5 ++-- drivers/gpu/drm/vmwgfx/vmwgfx_drv.h | 10 +++---- drivers/gpu/drm/vmwgfx/vmwgfx_resource.c | 33 +++++++++++++++++------- 3 files changed, 32 insertions(+), 16 deletions(-)
diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_bo.c b/drivers/gpu/drm/vmwgfx/vmwgfx_bo.c index 869aeaec2f86..18e4b329e563 100644 --- a/drivers/gpu/drm/vmwgfx/vmwgfx_bo.c +++ b/drivers/gpu/drm/vmwgfx/vmwgfx_bo.c @@ -463,6 +463,7 @@ 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); } @@ -479,6 +480,7 @@ 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); } @@ -514,8 +516,7 @@ 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, diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_drv.h b/drivers/gpu/drm/vmwgfx/vmwgfx_drv.h index 7944dbbbdd72..53f8522ae032 100644 --- a/drivers/gpu/drm/vmwgfx/vmwgfx_drv.h +++ b/drivers/gpu/drm/vmwgfx/vmwgfx_drv.h @@ -100,7 +100,7 @@ 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 @@ -109,7 +109,7 @@ 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; @@ -157,8 +157,8 @@ 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. @@ -179,8 +179,8 @@ 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); @@ -733,7 +733,7 @@ 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); }
/** diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_resource.c b/drivers/gpu/drm/vmwgfx/vmwgfx_resource.c index e4c97a4cf2ff..328ad46076ff 100644 --- a/drivers/gpu/drm/vmwgfx/vmwgfx_resource.c +++ b/drivers/gpu/drm/vmwgfx/vmwgfx_resource.c @@ -40,11 +40,24 @@ 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;
dma_resv_assert_held(res->backup->base.base.resv); 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); }
@@ -58,7 +71,8 @@ void vmw_resource_mob_detach(struct vmw_resource *res)
dma_resv_assert_held(backup->base.base.resv); 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); } } @@ -204,8 +218,8 @@ 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; @@ -754,19 +768,20 @@ 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 };
dma_resv_assert_held(vbo->base.base.resv); - 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);
- (void) res->func->unbind(res, res->res_dirty, &val_buf); res->backup_dirty = true; res->res_dirty = false; vmw_resource_mob_detach(res);