Store microtask queues in their global (fixes #18467)

7 files changed, 29 insertions, 78 deletions

diff --git a/components/script/dom/dedicatedworkerglobalscope.rs b/components/script/dom/dedicatedworkerglobalscope.rs
index 9c4949027b9..8ea89562f39 100644
--- a/components/script/dom/dedicatedworkerglobalscope.rs
+++ b/components/script/dom/dedicatedworkerglobalscope.rs
@@ -247,7 +247,7 @@ impl DedicatedWorkerGlobalScope {
                     global.handle_event(event);
                     // Step 6
                     let _ar = AutoWorkerReset::new(&global, worker.clone());
-                    global.upcast::<WorkerGlobalScope>().perform_a_microtask_checkpoint();
+                    global.upcast::<GlobalScope>().perform_a_microtask_checkpoint();
                 }
             }, reporter_name, parent_sender, CommonScriptMsg::CollectReports);
         }).expect("Thread spawning failed");
diff --git a/components/script/dom/dissimilaroriginwindow.rs b/components/script/dom/dissimilaroriginwindow.rs
index f54236c7766..6b0745a72e5 100644
--- a/components/script/dom/dissimilaroriginwindow.rs
+++ b/components/script/dom/dissimilaroriginwindow.rs
@@ -63,6 +63,9 @@ impl DissimilarOriginWindow {
                 global_to_clone_from.resource_threads().clone(),
                 timer_event_chan,
                 global_to_clone_from.origin().clone(),
+                // FIXME(nox): The microtask queue is probably not important
+                // here, but this whole DOM interface is a hack anyway.
+                global_to_clone_from.microtask_queue().clone(),
             ),
             window_proxy: JS::from_ref(window_proxy),
             location: Default::default(),
diff --git a/components/script/dom/globalscope.rs b/components/script/dom/globalscope.rs
index 90f5b7a9596..681953defdd 100644
--- a/components/script/dom/globalscope.rs
+++ b/components/script/dom/globalscope.rs
@@ -33,7 +33,7 @@ use js::jsapi::{JS_GetObjectRuntime, MutableHandleValue};
 use js::panic::maybe_resume_unwind;
 use js::rust::{CompileOptionsWrapper, Runtime, get_object_class};
 use libc;
-use microtask::Microtask;
+use microtask::{Microtask, MicrotaskQueue};
 use msg::constellation_msg::PipelineId;
 use net_traits::{CoreResourceThread, ResourceThreads, IpcSend};
 use profile_traits::{mem, time};
@@ -46,6 +46,7 @@ use std::cell::Cell;
 use std::collections::HashMap;
 use std::collections::hash_map::Entry;
 use std::ffi::CString;
+use std::rc::Rc;
 use task_source::file_reading::FileReadingTaskSource;
 use task_source::networking::NetworkingTaskSource;
 use task_source::performance_timeline::PerformanceTimelineTaskSource;
@@ -99,6 +100,15 @@ pub struct GlobalScope {
 
     /// The origin of the globalscope
     origin: MutableOrigin,
+
+    /// The microtask queue associated with this global.
+    ///
+    /// It is refcounted because windows in the same script thread share the
+    /// same microtask queue.
+    ///
+    /// https://html.spec.whatwg.org/multipage/#microtask-queue
+    #[ignore_heap_size_of = "Rc<T> is hard"]
+    microtask_queue: Rc<MicrotaskQueue>,
 }
 
 impl GlobalScope {
@@ -112,6 +122,7 @@ impl GlobalScope {
         resource_threads: ResourceThreads,
         timer_event_chan: IpcSender<TimerEvent>,
         origin: MutableOrigin,
+        microtask_queue: Rc<MicrotaskQueue>,
     ) -> Self {
         Self {
             eventtarget: EventTarget::new_inherited(),
@@ -129,6 +140,7 @@ impl GlobalScope {
             resource_threads,
             timers: OneshotTimers::new(timer_event_chan, scheduler_chan),
             origin,
+            microtask_queue,
         }
     }
 
@@ -479,30 +491,12 @@ impl GlobalScope {
 
     /// Perform a microtask checkpoint.
     pub fn perform_a_microtask_checkpoint(&self) {
-        if let Some(window) = self.downcast::<Window>() {
-            return window.perform_a_microtask_checkpoint();
-        }
-        if let Some(worker) = self.downcast::<WorkerGlobalScope>() {
-            return worker.perform_a_microtask_checkpoint();
-        }
-        if let Some(worker) = self.downcast::<WorkletGlobalScope>() {
-            return worker.perform_a_microtask_checkpoint();
-        }
-        unreachable!();
+        self.microtask_queue.checkpoint(|_| Some(Root::from_ref(self)));
     }
 
     /// Enqueue a microtask for subsequent execution.
     pub fn enqueue_microtask(&self, job: Microtask) {
-        if let Some(window) = self.downcast::<Window>() {
-            return window.enqueue_microtask(job);
-        }
-        if let Some(worker) = self.downcast::<WorkerGlobalScope>() {
-            return worker.enqueue_microtask(job);
-        }
-        if let Some(worker) = self.downcast::<WorkletGlobalScope>() {
-            return worker.enqueue_microtask(job);
-        }
-        unreachable!();
+        self.microtask_queue.enqueue(job);
     }
 
     /// Create a new sender/receiver pair that can be used to implement an on-demand
@@ -518,6 +512,11 @@ impl GlobalScope {
         unreachable!();
     }
 
+    /// Returns the microtask queue of this global.
+    pub fn microtask_queue(&self) -> &Rc<MicrotaskQueue> {
+        &self.microtask_queue
+    }
+
     /// Process a single event as if it were the next event
     /// in the thread queue for this global scope.
     pub fn process_event(&self, msg: CommonScriptMsg) {
diff --git a/components/script/dom/serviceworkerglobalscope.rs b/components/script/dom/serviceworkerglobalscope.rs
index e16707a77c6..de0cbb2e8af 100644
--- a/components/script/dom/serviceworkerglobalscope.rs
+++ b/components/script/dom/serviceworkerglobalscope.rs
@@ -219,7 +219,7 @@ impl ServiceWorkerGlobalScope {
                         break;
                     }
                     // Step 6
-                    global.upcast::<WorkerGlobalScope>().perform_a_microtask_checkpoint();
+                    global.upcast::<GlobalScope>().perform_a_microtask_checkpoint();
                 }
             }, reporter_name, scope.script_chan(), CommonScriptMsg::CollectReports);
         }).expect("Thread spawning failed");
diff --git a/components/script/dom/window.rs b/components/script/dom/window.rs
index 56022e66f01..51d58eb77dc 100644
--- a/components/script/dom/window.rs
+++ b/components/script/dom/window.rs
@@ -59,7 +59,7 @@ use js::jsapi::{JS_GC, JS_GetRuntime};
 use js::jsval::UndefinedValue;
 use js::rust::Runtime;
 use layout_image::fetch_image_for_layout;
-use microtask::{Microtask, MicrotaskQueue};
+use microtask::MicrotaskQueue;
 use msg::constellation_msg::{FrameType, PipelineId};
 use net_traits::{ResourceThreads, ReferrerPolicy};
 use net_traits::image_cache::{ImageCache, ImageResponder, ImageResponse};
@@ -288,10 +288,6 @@ pub struct Window {
     test_worklet: MutNullableJS<Worklet>,
     /// https://drafts.css-houdini.org/css-paint-api-1/#paint-worklet
     paint_worklet: MutNullableJS<Worklet>,
-
-    /// https://html.spec.whatwg.org/multipage/#microtask-queue
-    #[ignore_heap_size_of = "Rc<T> is hard"]
-    microtask_queue: Rc<MicrotaskQueue>,
 }
 
 impl Window {
@@ -1790,16 +1786,6 @@ impl Window {
             .send(msg)
             .unwrap();
     }
-
-    pub fn enqueue_microtask(&self, job: Microtask) {
-        self.microtask_queue.enqueue(job);
-    }
-
-    pub fn perform_a_microtask_checkpoint(&self) {
-        self.microtask_queue.checkpoint(|_| {
-            Some(Root::from_ref(self.upcast::<GlobalScope>()))
-        });
-    }
 }
 
 impl Window {
@@ -1855,6 +1841,7 @@ impl Window {
                 resource_threads,
                 timer_event_chan,
                 origin,
+                microtask_queue,
             ),
             script_chan,
             dom_manipulation_task_source,
@@ -1906,7 +1893,6 @@ impl Window {
             unminified_js_dir: Default::default(),
             test_worklet: Default::default(),
             paint_worklet: Default::default(),
-            microtask_queue,
         };
 
         unsafe {
diff --git a/components/script/dom/workerglobalscope.rs b/components/script/dom/workerglobalscope.rs
index 5cbd2ecc997..ebcebef6c27 100644
--- a/components/script/dom/workerglobalscope.rs
+++ b/components/script/dom/workerglobalscope.rs
@@ -30,7 +30,6 @@ use js::jsapi::{HandleValue, JSAutoCompartment, JSContext, JSRuntime};
 use js::jsval::UndefinedValue;
 use js::panic::maybe_resume_unwind;
 use js::rust::Runtime;
-use microtask::{MicrotaskQueue, Microtask};
 use net_traits::{IpcSend, load_whole_resource};
 use net_traits::request::{CredentialsMode, Destination, RequestInit as NetRequestInit, Type as RequestType};
 use script_runtime::{CommonScriptMsg, ScriptChan, ScriptPort};
@@ -91,10 +90,6 @@ pub struct WorkerGlobalScope {
     /// `IpcSender` doesn't exist
     from_devtools_receiver: Receiver<DevtoolScriptControlMsg>,
 
-    /// https://html.spec.whatwg.org/multipage/#microtask-queue
-    #[ignore_heap_size_of = "Rc<T> is hard"]
-    microtask_queue: Rc<MicrotaskQueue>,
-
     navigation_start_precise: f64,
     performance: MutNullableJS<Performance>,
 }
@@ -119,6 +114,7 @@ impl WorkerGlobalScope {
                 init.resource_threads,
                 timer_event_chan,
                 MutableOrigin::new(init.origin),
+                Default::default(),
             ),
             worker_id: init.worker_id,
             worker_url,
@@ -128,7 +124,6 @@ impl WorkerGlobalScope {
             navigator: Default::default(),
             from_devtools_sender: init.from_devtools_sender,
             from_devtools_receiver,
-            microtask_queue: Default::default(),
             navigation_start_precise: precise_time_ns() as f64,
             performance: Default::default(),
         }
@@ -171,18 +166,6 @@ impl WorkerGlobalScope {
             cancelled: self.closing.clone(),
         }
     }
-
-    pub fn enqueue_microtask(&self, job: Microtask) {
-        self.microtask_queue.enqueue(job);
-    }
-
-    pub fn perform_a_microtask_checkpoint(&self) {
-        self.microtask_queue.checkpoint(|id| {
-            let global = self.upcast::<GlobalScope>();
-            assert_eq!(global.pipeline_id(), id);
-            Some(Root::from_ref(global))
-        });
-    }
 }
 
 impl WorkerGlobalScopeMethods for WorkerGlobalScope {
diff --git a/components/script/dom/workletglobalscope.rs b/components/script/dom/workletglobalscope.rs
index 28c8cc27e7a..64a2b3199fb 100644
--- a/components/script/dom/workletglobalscope.rs
+++ b/components/script/dom/workletglobalscope.rs
@@ -17,8 +17,6 @@ use ipc_channel::ipc::IpcSender;
 use js::jsapi::JSContext;
 use js::jsval::UndefinedValue;
 use js::rust::Runtime;
-use microtask::Microtask;
-use microtask::MicrotaskQueue;
 use msg::constellation_msg::PipelineId;
 use net_traits::ResourceThreads;
 use net_traits::image_cache::ImageCache;
@@ -36,7 +34,6 @@ use script_traits::TimerSchedulerMsg;
 use servo_url::ImmutableOrigin;
 use servo_url::MutableOrigin;
 use servo_url::ServoUrl;
-use std::rc::Rc;
 use std::sync::Arc;
 use std::sync::mpsc::Sender;
 
@@ -47,9 +44,6 @@ pub struct WorkletGlobalScope {
     globalscope: GlobalScope,
     /// The base URL for this worklet.
     base_url: ServoUrl,
-    /// https://html.spec.whatwg.org/multipage/#microtask-queue
-    #[ignore_heap_size_of = "Rc<T> is hard"]
-    microtask_queue: Rc<MicrotaskQueue>,
     /// Sender back to the script thread
     #[ignore_heap_size_of = "channels are hard"]
     to_script_thread_sender: Sender<MainThreadScriptMsg>,
@@ -82,9 +76,9 @@ impl WorkletGlobalScope {
                 init.resource_threads.clone(),
                 timer_event_chan,
                 MutableOrigin::new(ImmutableOrigin::new_opaque()),
+                Default::default(),
             ),
             base_url,
-            microtask_queue: Default::default(),
             to_script_thread_sender: init.to_script_thread_sender.clone(),
             executor,
         }
@@ -133,20 +127,6 @@ impl WorkletGlobalScope {
         self.executor.clone()
     }
 
-    /// Queue up a microtask to be executed in this global.
-    pub fn enqueue_microtask(&self, job: Microtask) {
-        self.microtask_queue.enqueue(job);
-    }
-
-    /// Perform any queued microtasks.
-    pub fn perform_a_microtask_checkpoint(&self) {
-        self.microtask_queue.checkpoint(|id| {
-            let global = self.upcast::<GlobalScope>();
-            assert_eq!(global.pipeline_id(), id);
-            Some(Root::from_ref(global))
-        });
-    }
-
     /// Perform a worklet task
     pub fn perform_a_worklet_task(&self, task: WorkletTask) {
         match task {