Don't go through the layout thread to retrieve a node's primary style

components/layout/query.rs

@@ -22,7 +22,7 @@ use msg::constellation_msg::PipelineId;
 use script_layout_interface::rpc::TextIndexResponse;
 use script_layout_interface::rpc::{ContentBoxResponse, ContentBoxesResponse, LayoutRPC};
 use script_layout_interface::rpc::{NodeGeometryResponse, NodeScrollIdResponse};
-use script_layout_interface::rpc::{OffsetParentResponse, ResolvedStyleResponse, StyleResponse};
+use script_layout_interface::rpc::{OffsetParentResponse, ResolvedStyleResponse};
 use script_layout_interface::wrapper_traits::{
     LayoutNode, ThreadSafeLayoutElement, ThreadSafeLayoutNode,
 };
@@ -76,9 +76,6 @@ pub struct LayoutThreadData {
     /// A queued response for the offset parent/rect of a node.
     pub offset_parent_response: OffsetParentResponse,
 
-    /// A queued response for the style of a node.
-    pub style_response: StyleResponse,
-
     /// Scroll offsets of scrolling regions.
     pub scroll_offsets: ScrollOffsetMap,
 
@@ -179,12 +176,6 @@ impl LayoutRPC for LayoutRPCImpl {
         rw_data.offset_parent_response.clone()
     }
 
-    fn style(&self) -> StyleResponse {
-        let &LayoutRPCImpl(ref rw_data) = self;
-        let rw_data = rw_data.lock().unwrap();
-        rw_data.style_response.clone()
-    }
-
     fn text_index(&self) -> TextIndexResponse {
         let &LayoutRPCImpl(ref rw_data) = self;
         let rw_data = rw_data.lock().unwrap();
@@ -965,13 +956,6 @@ pub fn process_offset_parent_query(
     }
 }
 
-pub fn process_style_query<'dom>(requested_node: impl LayoutNode<'dom>) -> StyleResponse {
-    let element = requested_node.as_element().unwrap();
-    let data = element.borrow_data();
-
-    StyleResponse(data.map(|d| d.styles.primary().clone()))
-}
-
 enum InnerTextItem {
     Text(String),
     RequiredLineBreakCount(u32),

components/layout_2020/query.rs

@@ -15,7 +15,7 @@ use msg::constellation_msg::PipelineId;
 use script_layout_interface::rpc::TextIndexResponse;
 use script_layout_interface::rpc::{ContentBoxResponse, ContentBoxesResponse, LayoutRPC};
 use script_layout_interface::rpc::{NodeGeometryResponse, NodeScrollIdResponse};
-use script_layout_interface::rpc::{OffsetParentResponse, ResolvedStyleResponse, StyleResponse};
+use script_layout_interface::rpc::{OffsetParentResponse, ResolvedStyleResponse};
 use script_layout_interface::wrapper_traits::{LayoutNode, ThreadSafeLayoutNode};
 use script_traits::LayoutMsg as ConstellationMsg;
 use script_traits::UntrustedNodeAddress;
@@ -59,9 +59,6 @@ pub struct LayoutThreadData {
     /// A queued response for the offset parent/rect of a node.
     pub offset_parent_response: OffsetParentResponse,
 
-    /// A queued response for the style of a node.
-    pub style_response: StyleResponse,
-
     /// Scroll offsets of scrolling regions.
     pub scroll_offsets: HashMap<ExternalScrollId, Vector2D<f32, LayoutPixel>>,
 
@@ -139,12 +136,6 @@ impl LayoutRPC for LayoutRPCImpl {
         rw_data.offset_parent_response.clone()
     }
 
-    fn style(&self) -> StyleResponse {
-        let &LayoutRPCImpl(ref rw_data) = self;
-        let rw_data = rw_data.lock().unwrap();
-        rw_data.style_response.clone()
-    }
-
     fn text_index(&self) -> TextIndexResponse {
         let &LayoutRPCImpl(ref rw_data) = self;
         let rw_data = rw_data.lock().unwrap();
@@ -220,10 +211,6 @@ pub fn process_offset_parent_query(_requested_node: OpaqueNode) -> OffsetParentR
     OffsetParentResponse::empty()
 }
 
-pub fn process_style_query<'dom>(_requested_node: impl LayoutNode<'dom>) -> StyleResponse {
-    StyleResponse(None)
-}
-
 // https://html.spec.whatwg.org/multipage/#the-innertext-idl-attribute
 pub fn process_element_inner_text_query<'dom>(_node: impl LayoutNode<'dom>) -> String {
     "".to_owned()

components/layout_thread/lib.rs

@@ -55,9 +55,7 @@ use layout::query::{
     process_content_box_request, process_content_boxes_request, LayoutRPCImpl, LayoutThreadData,
 };
 use layout::query::{process_node_scroll_area_request, process_node_scroll_id_request};
-use layout::query::{
-    process_offset_parent_query, process_resolved_style_request, process_style_query,
-};
+use layout::query::{process_offset_parent_query, process_resolved_style_request};
 use layout::sequential;
 use layout::traversal::{
     ComputeStackingRelativePositions, PreorderFlowTraversal, RecalcStyleAndConstructFlows,
@@ -80,7 +78,7 @@ use profile_traits::time::{TimerMetadataFrameType, TimerMetadataReflowType};
 use script_layout_interface::message::{LayoutThreadInit, Msg, NodesFromPointQueryType, Reflow};
 use script_layout_interface::message::{QueryMsg, ReflowComplete, ReflowGoal, ScriptReflow};
 use script_layout_interface::rpc::TextIndexResponse;
-use script_layout_interface::rpc::{LayoutRPC, OffsetParentResponse, StyleResponse};
+use script_layout_interface::rpc::{LayoutRPC, OffsetParentResponse};
 use script_layout_interface::wrapper_traits::LayoutNode;
 use script_traits::{ConstellationControlMsg, LayoutControlMsg, LayoutMsg as ConstellationMsg};
 use script_traits::{DrawAPaintImageResult, IFrameSizeMsg, PaintWorkletError, WindowSizeType};
@@ -595,7 +593,6 @@ impl LayoutThread {
                 scroll_area_response: Rect::zero(),
                 resolved_style_response: String::new(),
                 offset_parent_response: OffsetParentResponse::empty(),
-                style_response: StyleResponse(None),
                 scroll_offsets: HashMap::new(),
                 text_index_response: TextIndexResponse(None),
                 nodes_from_point_response: vec![],
@@ -1308,9 +1305,7 @@ impl LayoutThread {
                         &QueryMsg::OffsetParentQuery(_) => {
                             rw_data.offset_parent_response = OffsetParentResponse::empty();
                         },
-                        &QueryMsg::StyleQuery(_) => {
-                            rw_data.style_response = StyleResponse(None);
-                        },
+                        &QueryMsg::StyleQuery => {},
                         &QueryMsg::TextIndexQuery(..) => {
                             rw_data.text_index_response = TextIndexResponse(None);
                         },
@@ -1634,10 +1629,7 @@ impl LayoutThread {
                 &QueryMsg::OffsetParentQuery(node) => {
                     rw_data.offset_parent_response = process_offset_parent_query(node, root_flow);
                 },
-                &QueryMsg::StyleQuery(node) => {
-                    let node = unsafe { ServoLayoutNode::new(&node) };
-                    rw_data.style_response = process_style_query(node);
-                },
+                &QueryMsg::StyleQuery => {},
                 &QueryMsg::NodesFromPointQuery(client_point, ref reflow_goal) => {
                     let mut flags = match reflow_goal {
                         &NodesFromPointQueryType::Topmost => webrender_api::HitTestFlags::empty(),

components/layout_thread_2020/lib.rs

@@ -42,8 +42,7 @@ use layout::query::{
 use layout::query::{process_element_inner_text_query, process_node_geometry_request};
 use layout::query::{process_node_scroll_area_request, process_node_scroll_id_request};
 use layout::query::{
-    process_offset_parent_query, process_resolved_style_request, process_style_query,
-    process_text_index_request,
+    process_offset_parent_query, process_resolved_style_request, process_text_index_request,
 };
 use layout::traversal::RecalcStyle;
 use layout::{BoxTreeRoot, FragmentTreeRoot};
@@ -64,7 +63,7 @@ use profile_traits::time::{TimerMetadataFrameType, TimerMetadataReflowType};
 use script_layout_interface::message::{LayoutThreadInit, Msg, NodesFromPointQueryType};
 use script_layout_interface::message::{QueryMsg, ReflowComplete, ReflowGoal, ScriptReflow};
 use script_layout_interface::rpc::TextIndexResponse;
-use script_layout_interface::rpc::{LayoutRPC, OffsetParentResponse, StyleResponse};
+use script_layout_interface::rpc::{LayoutRPC, OffsetParentResponse};
 use script_traits::{ConstellationControlMsg, LayoutControlMsg, LayoutMsg as ConstellationMsg};
 use script_traits::{DrawAPaintImageResult, PaintWorkletError};
 use script_traits::{Painter, WebrenderIpcSender};
@@ -551,7 +550,6 @@ impl LayoutThread {
                 scroll_area_response: Rect::zero(),
                 resolved_style_response: String::new(),
                 offset_parent_response: OffsetParentResponse::empty(),
-                style_response: StyleResponse(None),
                 scroll_offsets: HashMap::new(),
                 text_index_response: TextIndexResponse(None),
                 nodes_from_point_response: vec![],
@@ -978,9 +976,7 @@ impl LayoutThread {
                         &QueryMsg::OffsetParentQuery(_) => {
                             rw_data.offset_parent_response = OffsetParentResponse::empty();
                         },
-                        &QueryMsg::StyleQuery(_) => {
-                            rw_data.style_response = StyleResponse(None);
-                        },
+                        &QueryMsg::StyleQuery => {},
                         &QueryMsg::TextIndexQuery(..) => {
                             rw_data.text_index_response = TextIndexResponse(None);
                         },
@@ -1261,10 +1257,7 @@ impl LayoutThread {
                 &QueryMsg::OffsetParentQuery(node) => {
                     rw_data.offset_parent_response = process_offset_parent_query(node);
                 },
-                &QueryMsg::StyleQuery(node) => {
-                    let node = unsafe { ServoLayoutNode::new(&node) };
-                    rw_data.style_response = process_style_query(node);
-                },
+                &QueryMsg::StyleQuery => {},
                 &QueryMsg::NodesFromPointQuery(client_point, ref reflow_goal) => {
                     let mut flags = match reflow_goal {
                         &NodesFromPointQueryType::Topmost => webrender_api::HitTestFlags::empty(),

components/script/devtools.rs

@@ -15,7 +15,6 @@ use crate::dom::document::AnimationFrameCallback;
 use crate::dom::element::Element;
 use crate::dom::globalscope::GlobalScope;
 use crate::dom::node::{window_from_node, Node, ShadowIncluding};
-use crate::dom::window::Window;
 use crate::realms::enter_realm;
 use crate::script_thread::Documents;
 use devtools_traits::{AutoMargins, ComputedNodeLayout, TimelineMarkerType};
@@ -150,7 +149,7 @@ pub fn handle_get_layout(
             position: String::from(computed_style.Position()),
             zIndex: String::from(computed_style.ZIndex()),
             boxSizing: String::from(computed_style.BoxSizing()),
-            autoMargins: determine_auto_margins(&window, &*node),
+            autoMargins: determine_auto_margins(&node),
             marginTop: String::from(computed_style.MarginTop()),
             marginRight: String::from(computed_style.MarginRight()),
             marginBottom: String::from(computed_style.MarginBottom()),
@@ -169,8 +168,8 @@ pub fn handle_get_layout(
         .unwrap();
 }
 
-fn determine_auto_margins(window: &Window, node: &Node) -> AutoMargins {
-    let style = window.style_query(node.to_trusted_node_address()).unwrap();
+fn determine_auto_margins(node: &Node) -> AutoMargins {
+    let style = node.style().unwrap();
     let margin = style.get_margin();
     AutoMargins {
         top: margin.margin_top.is_auto(),

components/script/dom/element.rs

@@ -396,7 +396,7 @@ impl Element {
     /// style will be `None` for elements in a `display: none` subtree. otherwise, the element has a
     /// layout box iff it doesn't have `display: none`.
     pub fn style(&self) -> Option<Arc<ComputedValues>> {
-        window_from_node(self).style_query(self.upcast::<Node>().to_trusted_node_address())
+        self.upcast::<Node>().style()
     }
 
     // https://drafts.csswg.org/cssom-view/#css-layout-box

components/script/dom/node.rs

@@ -75,6 +75,7 @@ use malloc_size_of::{MallocSizeOf, MallocSizeOfOps};
 use msg::constellation_msg::{BrowsingContextId, PipelineId};
 use net_traits::image::base::{Image, ImageMetadata};
 use ref_slice::ref_slice;
+use script_layout_interface::message::QueryMsg;
 use script_layout_interface::{HTMLCanvasData, HTMLMediaData, LayoutElementType, LayoutNodeType};
 use script_layout_interface::{SVGSVGData, StyleAndOpaqueLayoutData, TrustedNodeAddress};
 use script_traits::DocumentActivity;
@@ -95,6 +96,7 @@ use std::ops::Range;
 use std::sync::Arc as StdArc;
 use style::context::QuirksMode;
 use style::dom::OpaqueNode;
+use style::properties::ComputedValues;
 use style::selector_parser::{SelectorImpl, SelectorParser};
 use style::stylesheets::Stylesheet;
 use uuid::Uuid;
@@ -1229,6 +1231,23 @@ impl Node {
             _ => false,
         }
     }
+
+    #[allow(unsafe_code)]
+    pub fn style(&self) -> Option<Arc<ComputedValues>> {
+        if !window_from_node(self).layout_reflow(QueryMsg::StyleQuery) {
+            return None;
+        }
+        unsafe {
+            (*self.style_and_layout_data.get()).as_ref().map(|data| {
+                data.style_data
+                    .element_data
+                    .borrow()
+                    .styles
+                    .primary()
+                    .clone()
+            })
+        }
+    }
 }
 
 /// Iterate through `nodes` until we find a `Node` that is not in `not_in`

components/script/dom/window.rs

@@ -131,7 +131,7 @@ use style::dom::OpaqueNode;
 use style::error_reporting::{ContextualParseError, ParseErrorReporter};
 use style::media_queries;
 use style::parser::ParserContext as CssParserContext;
-use style::properties::{ComputedValues, PropertyId};
+use style::properties::PropertyId;
 use style::selector_parser::PseudoElement;
 use style::str::HTML_SPACE_CHARACTERS;
 use style::stylesheets::CssRuleType;
@@ -1904,13 +1904,6 @@ impl Window {
         (element, response.rect)
     }
 
-    pub fn style_query(&self, node: TrustedNodeAddress) -> Option<servo_arc::Arc<ComputedValues>> {
-        if !self.layout_reflow(QueryMsg::StyleQuery(node)) {
-            return None;
-        }
-        self.layout_rpc.style().0
-    }
-
     pub fn text_index_query(
         &self,
         node: &Node,
@@ -2461,7 +2454,7 @@ fn debug_reflow_events(id: PipelineId, reflow_goal: &ReflowGoal, reason: &Reflow
             &QueryMsg::NodeScrollIdQuery(_n) => "\tNodeScrollIdQuery",
             &QueryMsg::ResolvedStyleQuery(_, _, _) => "\tResolvedStyleQuery",
             &QueryMsg::OffsetParentQuery(_n) => "\tOffsetParentQuery",
-            &QueryMsg::StyleQuery(_n) => "\tStyleQuery",
+            &QueryMsg::StyleQuery => "\tStyleQuery",
             &QueryMsg::TextIndexQuery(..) => "\tTextIndexQuery",
             &QueryMsg::ElementInnerTextQuery(_) => "\tElementInnerTextQuery",
             &QueryMsg::InnerWindowDimensionsQuery(_) => "\tInnerWindowDimensionsQuery",

components/script_layout_interface/message.rs

@@ -122,7 +122,7 @@ pub enum QueryMsg {
     // garbage values such as `0xdeadbeef as *const _`, this is unsound.
     NodeScrollIdQuery(TrustedNodeAddress),
     ResolvedStyleQuery(TrustedNodeAddress, Option<PseudoElement>, PropertyId),
-    StyleQuery(TrustedNodeAddress),
+    StyleQuery,
     ElementInnerTextQuery(TrustedNodeAddress),
     InnerWindowDimensionsQuery(BrowsingContextId),
 }
@@ -153,7 +153,7 @@ impl ReflowGoal {
                 QueryMsg::NodeScrollIdQuery(_) |
                 QueryMsg::ResolvedStyleQuery(..) |
                 QueryMsg::OffsetParentQuery(_) |
-                QueryMsg::StyleQuery(_) => false,
+                QueryMsg::StyleQuery => false,
             },
         }
     }
@@ -175,7 +175,7 @@ impl ReflowGoal {
                 QueryMsg::ResolvedStyleQuery(..) |
                 QueryMsg::OffsetParentQuery(_) |
                 QueryMsg::InnerWindowDimensionsQuery(_) |
-                QueryMsg::StyleQuery(_) => false,
+                QueryMsg::StyleQuery => false,
             },
         }
     }

components/script_layout_interface/rpc.rs

@@ -6,8 +6,6 @@ use app_units::Au;
 use euclid::default::Rect;
 use euclid::Size2D;
 use script_traits::UntrustedNodeAddress;
-use servo_arc::Arc;
-use style::properties::ComputedValues;
 use style_traits::CSSPixel;
 use webrender_api::ExternalScrollId;
 
@@ -33,9 +31,6 @@ pub trait LayoutRPC {
     /// Query layout for the resolved value of a given CSS property
     fn resolved_style(&self) -> ResolvedStyleResponse;
     fn offset_parent(&self) -> OffsetParentResponse;
-    /// Requests the styles for an element. Contains a `None` value if the element is in a `display:
-    /// none` subtree.
-    fn style(&self) -> StyleResponse;
     fn text_index(&self) -> TextIndexResponse;
     /// Requests the list of nodes from the given point.
     fn nodes_from_point_response(&self) -> Vec<UntrustedNodeAddress>;
@@ -72,8 +67,5 @@ impl OffsetParentResponse {
     }
 }
 
-#[derive(Clone)]
-pub struct StyleResponse(pub Option<Arc<ComputedValues>>);
-
 #[derive(Clone)]
 pub struct TextIndexResponse(pub Option<usize>);