Move hasPendingActivity from ActiveDOMObject to ScriptWrappable

third_party/WebKit/Source/bindings/core/v8/V8GCController.cpp

 /*
  * Copyright (C) 2009 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 12 matching lines @@
  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
 #include "bindings/core/v8/V8GCController.h"
 
+#include "bindings/core/v8/NPV8Object.h"
 #include "bindings/core/v8/RetainedDOMInfo.h"
 #include "bindings/core/v8/V8AbstractEventListener.h"
 #include "bindings/core/v8/V8Binding.h"
 #include "bindings/core/v8/V8MutationObserver.h"
 #include "bindings/core/v8/V8Node.h"
 #include "bindings/core/v8/V8ScriptRunner.h"
 #include "bindings/core/v8/WrapperTypeInfo.h"
 #include "core/dom/Attr.h"
 #include "core/dom/Document.h"
 #include "core/dom/NodeTraversal.h"
@@ skipping 71 matching lines @@
         // MinorGC does not collect objects because it may be expensive to
         // update references during minorGC
         if (classId == WrapperTypeInfo::ObjectClassId) {
             v8::Persistent<v8::Object>::Cast(*value).MarkActive();
             return;
         }
 
         v8::Local<v8::Object> wrapper = v8::Local<v8::Object>::New(m_isolate, v8::Persistent<v8::Object>::Cast(*value));
         ASSERT(V8DOMWrapper::hasInternalFieldsSet(wrapper));
         const WrapperTypeInfo* type = toWrapperTypeInfo(wrapper);
-        ActiveDOMObject* activeDOMObject = type->toActiveDOMObject(wrapper);
-        if (activeDOMObject && activeDOMObject->hasPendingActivity()) {
-            v8::Persistent<v8::Object>::Cast(*value).MarkActive();
+        if (type != npObjectTypeInfo() && toScriptWrappable(wrapper)->hasPendingActivity())
             return;
-        }
 
         if (classId == WrapperTypeInfo::NodeClassId) {
             ASSERT(V8Node::hasInstance(wrapper, m_isolate));
             Node* node = V8Node::toImpl(wrapper);
             if (node->hasEventListeners()) {
                 v8::Persistent<v8::Object>::Cast(*value).MarkActive();
                 return;
             }
             // FIXME: Remove the special handling for image elements.
             // The same special handling is in V8GCController::opaqueRootForGC().
@@ skipping 33 matching lines @@
             return;
 
         v8::Local<v8::Object> wrapper = v8::Local<v8::Object>::New(m_isolate, v8::Persistent<v8::Object>::Cast(*value));
         ASSERT(V8DOMWrapper::hasInternalFieldsSet(wrapper));
 
         if (value->IsIndependent())
             return;
 
         const WrapperTypeInfo* type = toWrapperTypeInfo(wrapper);
 
-        ActiveDOMObject* activeDOMObject = type->toActiveDOMObject(wrapper);
-        if (activeDOMObject && activeDOMObject->hasPendingActivity()) {
+        if (type != npObjectTypeInfo() && toScriptWrappable(wrapper)->hasPendingActivity()) {
             m_isolate->SetObjectGroupId(*value, liveRootId());
             ++m_domObjectsWithPendingActivity;
         }
 
         if (classId == WrapperTypeInfo::NodeClassId) {
             ASSERT(V8Node::hasInstance(wrapper, m_isolate));
             Node* node = V8Node::toImpl(wrapper);
             if (node->hasEventListeners())
                 addReferencesForNodeWithEventListeners(m_isolate, node, v8::Persistent<v8::Object>::Cast(*value));
             Node* root = V8GCController::opaqueRootForGC(m_isolate, node);
@@ skipping 258 matching lines @@
 private:
     Visitor* m_visitor;
 };
 
 void V8GCController::traceDOMWrappers(v8::Isolate* isolate, Visitor* visitor)
 {
     DOMWrapperTracer tracer(visitor);
     isolate->VisitHandlesWithClassIds(&tracer);
 }
 
+class PendingActivityVisitor : public v8::PersistentHandleVisitor {
+public:
+    explicit PendingActivityVisitor(ExecutionContext* executionContext)
+        : m_executionContext(executionContext)
+        , m_pendingActivityFound(false)
+    {
+    }
+
+    void VisitPersistentHandle(v8::Persistent<v8::Value>* value, uint16_t classId) override
+    {

[kinuko, 2016/01/25 04:06:25]

Could we count how many # of handles this class visited and report it as a UMA
so that we can take a look at it while it's in Canary & whenever we have
performance concern?

[haraken, 2016/01/25 04:08:42]

Sounds nice. Will do.

+        // If we have already found any wrapper that has a pending activity,
+        // we don't need to check other wrappers.
+        if (m_pendingActivityFound)

[kinuko, 2016/01/25 04:06:25]

Would there be a way to exit the visitor loop once we found pending activity? 
...looks like we need v8 change which may not be worth doing unless we see perf
issue.

[haraken, 2016/01/25 04:08:42]

Yeah, in the current V8 API, we don't have a way to exit the loop earlier :/

+            return;
+
+        if (classId != WrapperTypeInfo::NodeClassId && classId != WrapperTypeInfo::ObjectClassId)
+            return;
+
+        const v8::Persistent<v8::Object>& wrapper = v8::Persistent<v8::Object>::Cast(*value);
+        const WrapperTypeInfo* type = toWrapperTypeInfo(wrapper);
+        // The ExecutionContext check is heavy, so it should be done at the last.
+        if (type != npObjectTypeInfo()
+            && toScriptWrappable(wrapper)->hasPendingActivity()
+            /* && toExecutionContext(v8::Object::CreationContext(wrapper)) == m_executionContext */

[haraken, 2016/01/22 17:15:44]

To enable this condition, I need to implement the V8 API (i.e.,
v8::Object::CreationContext). I'll do that before landing this CL.

(Note: Even if we don't enable the condition, it will not affect the correctness
-- it will just delay collecting a worker object of compositor workers, where
multiple ExecutionContexts are associated with one isolate.)

+            )
+            m_pendingActivityFound = true;
+    }
+
+    bool pendingActivityFound() const { return m_pendingActivityFound; }
+
+private:
+    RawPtrWillBePersistent<ExecutionContext> m_executionContext;
+    bool m_pendingActivityFound;
+};
+
+bool V8GCController::hasPendingActivity(ExecutionContext* executionContext)
+{
+    // V8GCController::hasPendingActivity is used only when a worker checks if
+    // the worker contains any wrapper that has pending activities.
+    ASSERT(!isMainThread());
+    PendingActivityVisitor visitor(executionContext);
+    toIsolate(executionContext)->VisitHandlesWithClassIds(&visitor);
+    return visitor.pendingActivityFound();
+}
+
 } // namespace blink