Bug 942240 - Improve the skippability of nsGlobalWindow, r=mccr8

--HG--
extra : rebase_source : ed7e687229a92075657d9b665fbc7af42d9eb5cc

content/base/src/nsCCUncollectableMarker.cpp

@@ -30,6 +30,7 @@
 #include "mozilla/dom/Element.h"
 #include "xpcpublic.h"
 #include "nsObserverService.h"
+#include "nsFocusManager.h"
 
 using namespace mozilla::dom;
 
@@ -210,6 +211,16 @@ MarkContentViewer(nsIContentViewer* aViewer, bool aCleanupJS,
         EnumerateAll(MarkUserData, &nsCCUncollectableMarker::sGeneration);
     }
   }
+  if (doc) {
+    nsPIDOMWindow* inner = doc->GetInnerWindow();
+    if (inner) {
+      inner->MarkUncollectableForCCGeneration(nsCCUncollectableMarker::sGeneration);
+    }
+    nsPIDOMWindow* outer = doc->GetWindow();
+    if (outer) {
+      outer->MarkUncollectableForCCGeneration(nsCCUncollectableMarker::sGeneration);
+    }
+  }
 }
 
 void MarkDocShell(nsIDocShellTreeNode* aNode, bool aCleanupJS,
@@ -336,6 +347,8 @@ nsCCUncollectableMarker::Observe(nsISupports* aSubject, const char* aTopic,
     ++sGeneration;
   }
 
+  nsFocusManager::MarkUncollectableForCCGeneration(sGeneration);
+
   nsresult rv;
 
   // Iterate all toplevel windows

dom/base/nsFocusManager.cpp

@@ -3436,6 +3436,43 @@ nsFocusManager::SetFocusedWindowInternal(nsPIDOMWindow* aWindow)
   mFocusedWindow = aWindow;
 }
 
+void
+nsFocusManager::MarkUncollectableForCCGeneration(uint32_t aGeneration)
+{
+  if (!sInstance) {
+    return;
+  }
+
+  if (sInstance->mActiveWindow) {
+    sInstance->mActiveWindow->
+      MarkUncollectableForCCGeneration(aGeneration);
+  }
+  if (sInstance->mFocusedWindow) {
+    sInstance->mFocusedWindow->
+      MarkUncollectableForCCGeneration(aGeneration);
+  }
+  if (sInstance->mWindowBeingLowered) {
+    sInstance->mWindowBeingLowered->
+      MarkUncollectableForCCGeneration(aGeneration);
+  }
+  if (sInstance->mFocusedContent) {
+    sInstance->mFocusedContent->OwnerDoc()->
+      MarkUncollectableForCCGeneration(aGeneration);
+  }
+  if (sInstance->mFirstBlurEvent) {
+    sInstance->mFirstBlurEvent->OwnerDoc()->
+      MarkUncollectableForCCGeneration(aGeneration);
+  }
+  if (sInstance->mFirstFocusEvent) {
+    sInstance->mFirstFocusEvent->OwnerDoc()->
+      MarkUncollectableForCCGeneration(aGeneration);
+  }
+  if (sInstance->mMouseDownEventHandlingDocument) {
+    sInstance->mMouseDownEventHandlingDocument->
+      MarkUncollectableForCCGeneration(aGeneration);
+  }
+}
+
 nsresult
 NS_NewFocusManager(nsIFocusManager** aResult)
 {

dom/base/nsFocusManager.h

@@ -121,6 +121,7 @@ public:
 
   static bool sMouseFocusesFormControl;
 
+  static void MarkUncollectableForCCGeneration(uint32_t aGeneration);
 protected:
 
   nsFocusManager();

dom/base/nsGlobalWindow.cpp

@@ -550,7 +550,8 @@ nsPIDOMWindow::nsPIDOMWindow(nsPIDOMWindow *aOuterWindow)
   mIsActive(false), mIsBackground(false),
   mInnerWindow(nullptr), mOuterWindow(aOuterWindow),
   // Make sure no actual window ends up with mWindowID == 0
-  mWindowID(++gNextWindowID), mHasNotifiedGlobalCreated(false)
+  mWindowID(++gNextWindowID), mHasNotifiedGlobalCreated(false),
+  mMarkedCCGeneration(0)
  {}
 
 nsPIDOMWindow::~nsPIDOMWindow() {}
@@ -1619,7 +1620,7 @@ MarkXBLHandlers(nsXBLPrototypeHandler* aKey, JS::Heap<JSObject*>& aData, void* a
 }
 
 NS_IMPL_CYCLE_COLLECTION_CAN_SKIP_BEGIN(nsGlobalWindow)
-  if (tmp->IsBlackForCC()) {
+  if (tmp->IsBlackForCC(false)) {
     if (tmp->mCachedXBLPrototypeHandlers) {
       tmp->mCachedXBLPrototypeHandlers->Enumerate(MarkXBLHandlers, nullptr);
     }
@@ -1632,11 +1633,11 @@ NS_IMPL_CYCLE_COLLECTION_CAN_SKIP_BEGIN(nsGlobalWindow)
 NS_IMPL_CYCLE_COLLECTION_CAN_SKIP_END
 
 NS_IMPL_CYCLE_COLLECTION_CAN_SKIP_IN_CC_BEGIN(nsGlobalWindow)
-  return tmp->IsBlackForCC();
+  return tmp->IsBlackForCC(true);
 NS_IMPL_CYCLE_COLLECTION_CAN_SKIP_IN_CC_END
 
 NS_IMPL_CYCLE_COLLECTION_CAN_SKIP_THIS_BEGIN(nsGlobalWindow)
-  return tmp->IsBlackForCC();
+  return tmp->IsBlackForCC(false);
 NS_IMPL_CYCLE_COLLECTION_CAN_SKIP_THIS_END
 
 inline void
@@ -1659,10 +1660,6 @@ NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN_INTERNAL(nsGlobalWindow)
     NS_IMPL_CYCLE_COLLECTION_DESCRIBE(nsGlobalWindow, tmp->mRefCnt.get())
   }
 
-  if (!cb.WantAllTraces() && tmp->IsBlackForCC()) {
-    return NS_SUCCESS_INTERRUPTED_TRAVERSE;
-  }
-
   NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mContext)
 
   NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mControllers)
@@ -1791,12 +1788,16 @@ NS_IMPL_CYCLE_COLLECTION_TRACE_BEGIN(nsGlobalWindow)
 NS_IMPL_CYCLE_COLLECTION_TRACE_END
 
 bool
-nsGlobalWindow::IsBlackForCC()
+nsGlobalWindow::IsBlackForCC(bool aTracingNeeded)
 {
-  return
-    (mDoc &&
-     nsCCUncollectableMarker::InGeneration(mDoc->GetMarkedCCGeneration())) ||
-    (nsCCUncollectableMarker::sGeneration && IsBlack());
+  if (!nsCCUncollectableMarker::sGeneration) {
+    return false;
+  }
+
+  return (nsCCUncollectableMarker::InGeneration(GetMarkedCCGeneration()) ||
+          IsBlack()) &&
+         (!aTracingNeeded ||
+          HasNothingToTrace(static_cast<nsIDOMEventTarget*>(this)));
 }
 
 void

dom/base/nsGlobalWindow.h

@@ -355,7 +355,7 @@ public:
   void PoisonOuterWindowProxy(JSObject *aObject);
   virtual void OnFinalize(JSObject* aObject);
 
-  virtual bool IsBlackForCC();
+  virtual bool IsBlackForCC(bool aTracingNeeded = true);
 
   // nsIScriptObjectPrincipal
   virtual nsIPrincipal* GetPrincipal();

dom/base/nsIScriptGlobalObject.h

@@ -27,8 +27,8 @@ NS_HandleScriptError(nsIScriptGlobalObject *aScriptGlobal,
 
 
 #define NS_ISCRIPTGLOBALOBJECT_IID \
-{ 0xa6c0bfae, 0x8be4, 0x4747, \
-  { 0xaf, 0x1a, 0xe3, 0xf0, 0x3f, 0xb6, 0x0e, 0xb8 } }
+{ 0x30c64680, 0x909a, 0x4435, \
+  { 0x90, 0x3b, 0x29, 0x3e, 0xb5, 0x5d, 0xc7, 0xa0 } }
 
 /**
  * The global object which keeps a script context for each supported script
@@ -80,7 +80,7 @@ public:
     return NS_OK;
   }
 
-  virtual bool IsBlackForCC() { return false; }
+  virtual bool IsBlackForCC(bool aTracingNeeded = true) { return false; }
 };
 
 NS_DEFINE_STATIC_IID_ACCESSOR(nsIScriptGlobalObject,

dom/base/nsPIDOMWindow.h

@@ -60,8 +60,8 @@ enum UIStateChangeType
 };
 
 #define NS_PIDOMWINDOW_IID \
-{ 0x4f4eadf9, 0xe795, 0x48e5, \
-  { 0x89, 0x4b, 0x04, 0x40, 0xb2, 0x5d, 0xa6, 0xfa } }
+{ 0xf26953de, 0xa799, 0x4a92, \
+  { 0x87, 0x49, 0x7c, 0x37, 0xe5, 0x90, 0x3f, 0x37 } }
 
 class nsPIDOMWindow : public nsIDOMWindowInternal
 {
@@ -653,6 +653,15 @@ public:
   // WebIDL-ish APIs
   nsPerformance* GetPerformance();
 
+  void MarkUncollectableForCCGeneration(uint32_t aGeneration)
+  {
+    mMarkedCCGeneration = aGeneration;
+  }
+
+  uint32_t GetMarkedCCGeneration()
+  {
+    return mMarkedCCGeneration;
+  }
 protected:
   // The nsPIDOMWindow constructor. The aOuterWindow argument should
   // be null if and only if the created window itself is an outer
@@ -736,6 +745,8 @@ protected:
   // This is only used by the inner window. Set to true once we've sent
   // the (chrome|content)-document-global-created notification.
   bool mHasNotifiedGlobalCreated;
+
+  uint32_t mMarkedCCGeneration;
 };
 
 

dom/base/nsWrapperCache.h

@@ -156,6 +156,8 @@ public:
    */
   bool IsBlackAndDoesNotNeedTracing(nsISupports* aThis);
 
+  bool HasNothingToTrace(nsISupports* aThis);
+
   // Only meant to be called by code that preserves a wrapper.
   void SetPreservingWrapper(bool aPreserve)
   {

dom/base/nsWrapperCacheInlines.h

@@ -36,17 +36,20 @@ SearchGray(void* aGCThing, const char* aName, void* aClosure)
   }
 }
 
+inline bool
+nsWrapperCache::HasNothingToTrace(nsISupports* aThis)
+{
+  nsXPCOMCycleCollectionParticipant* participant = nullptr;
+  CallQueryInterface(aThis, &participant);
+  bool hasGrayObjects = false;
+  participant->Trace(aThis, TraceCallbackFunc(SearchGray), &hasGrayObjects);
+  return !hasGrayObjects;
+}
+
 inline bool
 nsWrapperCache::IsBlackAndDoesNotNeedTracing(nsISupports* aThis)
 {
-  if (IsBlack()) {
-    nsXPCOMCycleCollectionParticipant* participant = nullptr;
-    CallQueryInterface(aThis, &participant);
-    bool hasGrayObjects = false;
-    participant->Trace(aThis, TraceCallbackFunc(SearchGray), &hasGrayObjects);
-    return !hasGrayObjects;
-  }
-  return false;
+  return IsBlack() && HasNothingToTrace(aThis);
 }
 
 inline void