Auto merge of #20307 - csmoe:measure_query_time, r=jdm

Measure time required before a layout query is serviced by the layout thread

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- [X] extract QueryMsg from ReflowGoal
- [X] introduce QueryMsg timestamp

---
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- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [x] These changes fix #19795 (github issue number if applicable).

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- [ ] There are tests for these changes OR
- [ ] These changes do not require tests because _____

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components/script/dom/window.rs

@@ -67,7 +67,7 @@ use profile_traits::ipc as ProfiledIpc;
 use profile_traits::mem::ProfilerChan as MemProfilerChan;
 use profile_traits::time::ProfilerChan as TimeProfilerChan;
 use script_layout_interface::{TrustedNodeAddress, PendingImageState};
-use script_layout_interface::message::{Msg, Reflow, ReflowGoal, ScriptReflow};
+use script_layout_interface::message::{Msg, Reflow, QueryMsg, ReflowGoal, ScriptReflow};
 use script_layout_interface::reporter::CSSErrorReporter;
 use script_layout_interface::rpc::{ContentBoxResponse, ContentBoxesResponse, LayoutRPC};
 use script_layout_interface::rpc::{NodeScrollIdResponse, ResolvedStyleResponse, TextIndexResponse};
@@ -1385,12 +1385,16 @@ impl Window {
         issued_reflow
     }
 
+    pub fn layout_reflow(&self, query_msg: QueryMsg) -> bool {
+        self.reflow(ReflowGoal::LayoutQuery(query_msg, time::precise_time_ns()), ReflowReason::Query)
+    }
+
     pub fn layout(&self) -> &LayoutRPC {
         &*self.layout_rpc
     }
 
     pub fn content_box_query(&self, content_box_request: TrustedNodeAddress) -> Option<Rect<Au>> {
-        if !self.reflow(ReflowGoal::ContentBoxQuery(content_box_request), ReflowReason::Query) {
+        if !self.layout_reflow(QueryMsg::ContentBoxQuery(content_box_request)) {
             return None;
         }
         let ContentBoxResponse(rect) = self.layout_rpc.content_box();
@@ -1398,7 +1402,7 @@ impl Window {
     }
 
     pub fn content_boxes_query(&self, content_boxes_request: TrustedNodeAddress) -> Vec<Rect<Au>> {
-        if !self.reflow(ReflowGoal::ContentBoxesQuery(content_boxes_request), ReflowReason::Query) {
+        if !self.layout_reflow(QueryMsg::ContentBoxesQuery(content_boxes_request)) {
             return vec![];
         }
         let ContentBoxesResponse(rects) = self.layout_rpc.content_boxes();
@@ -1406,14 +1410,14 @@ impl Window {
     }
 
     pub fn client_rect_query(&self, node_geometry_request: TrustedNodeAddress) -> Rect<i32> {
-        if !self.reflow(ReflowGoal::NodeGeometryQuery(node_geometry_request), ReflowReason::Query) {
+        if !self.layout_reflow(QueryMsg::NodeGeometryQuery(node_geometry_request)) {
             return Rect::zero();
         }
         self.layout_rpc.node_geometry().client_rect
     }
 
     pub fn scroll_area_query(&self, node: TrustedNodeAddress) -> Rect<i32> {
-        if !self.reflow(ReflowGoal::NodeScrollGeometryQuery(node), ReflowReason::Query) {
+        if !self.layout_reflow(QueryMsg::NodeScrollGeometryQuery(node)) {
             return Rect::zero();
         }
         self.layout_rpc.node_scroll_area().client_rect
@@ -1436,10 +1440,7 @@ impl Window {
         y_: f64,
         behavior: ScrollBehavior
     ) {
-        if !self.reflow(
-            ReflowGoal::NodeScrollIdQuery(node.to_trusted_node_address()),
-            ReflowReason::Query
-        ) {
+        if !self.layout_reflow(QueryMsg::NodeScrollIdQuery(node.to_trusted_node_address())) {
             return;
         }
 
@@ -1463,8 +1464,7 @@ impl Window {
                                 element: TrustedNodeAddress,
                                 pseudo: Option<PseudoElement>,
                                 property: PropertyId) -> DOMString {
-        if !self.reflow(ReflowGoal::ResolvedStyleQuery(element, pseudo, property),
-                        ReflowReason::Query) {
+        if !self.layout_reflow(QueryMsg::ResolvedStyleQuery(element, pseudo, property)) {
             return DOMString::new();
         }
         let ResolvedStyleResponse(resolved) = self.layout_rpc.resolved_style();
@@ -1473,7 +1473,7 @@ impl Window {
 
     #[allow(unsafe_code)]
     pub fn offset_parent_query(&self, node: TrustedNodeAddress) -> (Option<DomRoot<Element>>, Rect<Au>) {
-        if !self.reflow(ReflowGoal::OffsetParentQuery(node), ReflowReason::Query) {
+        if !self.layout_reflow(QueryMsg::OffsetParentQuery(node)) {
             return (None, Rect::zero());
         }
 
@@ -1488,7 +1488,7 @@ impl Window {
     }
 
     pub fn style_query(&self, node: TrustedNodeAddress) -> Option<servo_arc::Arc<ComputedValues>> {
-        if !self.reflow(ReflowGoal::StyleQuery(node), ReflowReason::Query) {
+        if !self.layout_reflow(QueryMsg::StyleQuery(node)) {
             return None
         }
         self.layout_rpc.style().0
@@ -1499,7 +1499,7 @@ impl Window {
         node: TrustedNodeAddress,
         point_in_node: Point2D<f32>
     ) -> TextIndexResponse {
-        if !self.reflow(ReflowGoal::TextIndexQuery(node, point_in_node), ReflowReason::Query) {
+        if !self.layout_reflow(QueryMsg::TextIndexQuery(node, point_in_node)) {
             return TextIndexResponse(None);
         }
         self.layout_rpc.text_index()
@@ -1881,18 +1881,20 @@ fn debug_reflow_events(id: PipelineId, reflow_goal: &ReflowGoal, reason: &Reflow
     let mut debug_msg = format!("**** pipeline={}", id);
     debug_msg.push_str(match *reflow_goal {
         ReflowGoal::Full => "\tFull",
-        ReflowGoal::ContentBoxQuery(_n) => "\tContentBoxQuery",
-        ReflowGoal::ContentBoxesQuery(_n) => "\tContentBoxesQuery",
-        ReflowGoal::NodesFromPointQuery(..) => "\tNodesFromPointQuery",
-        ReflowGoal::NodeGeometryQuery(_n) => "\tNodeGeometryQuery",
-        ReflowGoal::NodeScrollGeometryQuery(_n) => "\tNodeScrollGeometryQuery",
-        ReflowGoal::NodeScrollIdQuery(_n) => "\tNodeScrollIdQuery",
-        ReflowGoal::ResolvedStyleQuery(_, _, _) => "\tResolvedStyleQuery",
-        ReflowGoal::OffsetParentQuery(_n) => "\tOffsetParentQuery",
-        ReflowGoal::StyleQuery(_n) => "\tStyleQuery",
-        ReflowGoal::TextIndexQuery(..) => "\tTextIndexQuery",
         ReflowGoal::TickAnimations => "\tTickAnimations",
-        ReflowGoal::ElementInnerTextQuery(_) => "\tElementInnerTextQuery",
+        ReflowGoal::LayoutQuery(ref query_msg, _) => match query_msg {
+            &QueryMsg::ContentBoxQuery(_n) => "\tContentBoxQuery",
+            &QueryMsg::ContentBoxesQuery(_n) => "\tContentBoxesQuery",
+            &QueryMsg::NodesFromPointQuery(..) => "\tNodesFromPointQuery",
+            &QueryMsg::NodeGeometryQuery(_n) => "\tNodeGeometryQuery",
+            &QueryMsg::NodeScrollGeometryQuery(_n) => "\tNodeScrollGeometryQuery",
+            &QueryMsg::NodeScrollIdQuery(_n) => "\tNodeScrollIdQuery",
+            &QueryMsg::ResolvedStyleQuery(_, _, _) => "\tResolvedStyleQuery",
+            &QueryMsg::OffsetParentQuery(_n) => "\tOffsetParentQuery",
+            &QueryMsg::StyleQuery(_n) => "\tStyleQuery",
+            &QueryMsg::TextIndexQuery(..) => "\tTextIndexQuery",
+            &QueryMsg::ElementInnerTextQuery(_) => "\tElementInnerTextQuery",
+        },
     });
 
     debug_msg.push_str(match *reason {