Backout Bug 930793 because of talos regressions,r=backout

docshell/base/nsDocShell.cpp

@@ -200,6 +200,8 @@
 #include "nsIBrowserSearchService.h"
 #endif
 
+static NS_DEFINE_CID(kAppShellCID, NS_APPSHELL_CID);
+
 #if defined(DEBUG_bryner) || defined(DEBUG_chb)
 //#define DEBUG_DOCSHELL_FOCUS
 #define DEBUG_PAGE_CACHE
@@ -220,6 +222,9 @@ static bool gAddedPreferencesVarCache = false;
 
 bool nsDocShell::sUseErrorPages = false;
 
+// Number of documents currently loading
+static int32_t gNumberOfDocumentsLoading = 0;
+
 // Global count of existing docshells.
 static int32_t gDocShellCount = 0;
 
@@ -250,6 +255,18 @@ static PRLogModuleInfo* gDocShellLeakLog;
 const char kBrandBundleURL[]      = "chrome://branding/locale/brand.properties";
 const char kAppstringsBundleURL[] = "chrome://global/locale/appstrings.properties";
 
+static void
+FavorPerformanceHint(bool aPerfOverStarvation)
+{
+  nsCOMPtr<nsIAppShell> appShell = do_GetService(kAppShellCID);
+  if (appShell) {
+    appShell->FavorPerformanceHint(
+      aPerfOverStarvation,
+      Preferences::GetUint("docshell.event_starvation_delay_hint",
+                           NS_EVENT_STARVATION_DELAY_HINT));
+  }
+}
+
 //*****************************************************************************
 // <a ping> support
 //*****************************************************************************
@@ -7524,6 +7541,14 @@ nsDocShell::EndPageLoad(nsIWebProgress* aProgress,
     mIsExecutingOnLoadHandler = false;
 
     mEODForCurrentDocument = true;
+
+    // If all documents have completed their loading
+    // favor native event dispatch priorities
+    // over performance
+    if (--gNumberOfDocumentsLoading == 0) {
+      // Hint to use normal native event dispatch priorities
+      FavorPerformanceHint(false);
+    }
   }
   /* Check if the httpChannel has any cache-control related response headers,
    * like no-store, no-cache. If so, update SHEntry so that
@@ -8653,6 +8678,12 @@ nsDocShell::RestoreFromHistory()
   mSavingOldViewer = false;
   mEODForCurrentDocument = false;
 
+  // Tell the event loop to favor plevents over user events, see comments
+  // in CreateContentViewer.
+  if (++gNumberOfDocumentsLoading == 1) {
+    FavorPerformanceHint(true);
+  }
+
   if (oldCv && newCv) {
     newCv->SetMinFontSize(minFontSize);
     newCv->SetTextZoom(textZoom);
@@ -9065,6 +9096,16 @@ nsDocShell::CreateContentViewer(const nsACString& aContentType,
     }
   }
 
+  // Give hint to native plevent dispatch mechanism. If a document
+  // is loading the native plevent dispatch mechanism should favor
+  // performance over normal native event dispatch priorities.
+  if (++gNumberOfDocumentsLoading == 1) {
+    // Hint to favor performance for the plevent notification mechanism.
+    // We want the pages to load as fast as possible even if its means
+    // native messages might be starved.
+    FavorPerformanceHint(true);
+  }
+
   if (onLocationChangeNeeded) {
     FireOnLocationChange(this, aRequest, mCurrentURI, 0);
   }

dom/base/nsContentSink.cpp

@@ -201,6 +201,7 @@ nsContentSink::Init(nsIDocument* aDoc,
 
   if (sEnablePerfMode != 0) {
     mDynamicLowerValue = sEnablePerfMode == 1;
+    FavorPerformanceHint(!mDynamicLowerValue, 0);
   }
 
   return NS_OK;
@@ -1407,6 +1408,15 @@ nsContentSink::DidProcessATokenImpl()
 
 //----------------------------------------------------------------------
 
+void
+nsContentSink::FavorPerformanceHint(bool perfOverStarvation, uint32_t starvationDelay)
+{
+  static NS_DEFINE_CID(kAppShellCID, NS_APPSHELL_CID);
+  nsCOMPtr<nsIAppShell> appShell = do_GetService(kAppShellCID);
+  if (appShell)
+    appShell->FavorPerformanceHint(perfOverStarvation, starvationDelay);
+}
+
 void
 nsContentSink::BeginUpdate(nsIDocument *aDocument, nsUpdateType aUpdateType)
 {
@@ -1484,6 +1494,12 @@ nsContentSink::DropParserAndPerfHint(void)
   // reference.
   nsRefPtr<nsParserBase> kungFuDeathGrip(mParser.forget());
 
+  if (mDynamicLowerValue) {
+    // Reset the performance hint which was set to FALSE
+    // when mDynamicLowerValue was set.
+    FavorPerformanceHint(true, 0);
+  }
+
   if (!mRunsToCompletion) {
     mDocument->UnblockOnload(true);
   }
@@ -1521,6 +1537,7 @@ nsContentSink::WillParseImpl(void)
        (currentTime - lastEventTime) < uint32_t(sInteractiveTime));
     
     if (mDynamicLowerValue != newDynLower) {
+      FavorPerformanceHint(!newDynLower, 0);
       mDynamicLowerValue = newDynLower;
     }
   }

dom/base/nsContentSink.h

@@ -239,6 +239,8 @@ public:
   static void NotifyDocElementCreated(nsIDocument* aDoc);
 
 protected:
+  void
+  FavorPerformanceHint(bool perfOverStarvation, uint32_t starvationDelay);
 
   inline int32_t GetNotificationInterval()
   {

dom/tests/mochitest/general/test_vibrator.html

@@ -65,7 +65,7 @@ function tests(aEnabled) {
   expectSuccess([1000, 1000.1]);
 
   // The following loop shouldn't cause us to crash.  See bug 701716.
-  for (var i = 0; i < 1000; i++) {
+  for (var i = 0; i < 10000; i++) {
     navigator.vibrate([100, 100]);
   }
   ok(true, "Didn't crash after issuing a lot of vibrate() calls.");

dom/tests/mochitest/pointerlock/file_screenClientXYConst.html

@@ -51,9 +51,9 @@ https://bugzilla.mozilla.org/show_bug.cgi?id=633602
         var firstCall = !unLockedCoords;
         if (!firstCall) {
           todo(false, "mousemove is fired twice.");
-        } else {
-          isUnlocked = !document.mozPointerLockElement;
         }
+
+        isUnlocked = !document.mozPointerLockElement;
         unLockedCoords = {
           screenX: e.screenX,
           screenY: e.screenY,

layout/base/nsRefreshDriver.cpp

@@ -1722,7 +1722,7 @@ nsRefreshDriver::Tick(int64_t aNowEpoch, TimeStamp aNowTime)
 
     mViewManagerFlushIsPending = false;
     nsRefPtr<nsViewManager> vm = mPresContext->GetPresShell()->GetViewManager();
-    vm->ProcessPendingUpdates(nsViewManager::eTrySyncUpdate);
+    vm->ProcessPendingUpdates();
 #ifdef MOZ_DUMP_PAINTING
     if (nsLayoutUtils::InvalidationDebuggingIsEnabled()) {
       printf_stderr("Ending ProcessPendingUpdates\n");

view/nsViewManager.cpp

@@ -677,7 +677,7 @@ void nsViewManager::WillPaintWindow(nsIWidget* aWidget)
     LayerManager *manager = aWidget->GetLayerManager();
     if (view &&
         (view->ForcedRepaint() || !manager->NeedsWidgetInvalidation())) {
-      ProcessPendingUpdates(eNoSyncUpdate);
+      ProcessPendingUpdates();
       // Re-get the view pointer here since the ProcessPendingUpdates might have
       // destroyed it during CallWillPaintOnObservers.
       view = nsView::GetViewFor(aWidget);
@@ -1060,10 +1060,10 @@ nsViewManager::IsPainting(bool& aIsPainting)
 }
 
 void
-nsViewManager::ProcessPendingUpdates(UpdatingMode aMode)
+nsViewManager::ProcessPendingUpdates()
 {
   if (!IsRootVM()) {
-    RootViewManager()->ProcessPendingUpdates(aMode);
+    RootViewManager()->ProcessPendingUpdates();
     return;
   }
 
@@ -1075,14 +1075,6 @@ nsViewManager::ProcessPendingUpdates(UpdatingMode aMode)
 
     ProcessPendingUpdatesForView(mRootView, true);
   }
-
-  if (aMode == eTrySyncUpdate) {
-    nsCOMPtr<nsIWidget> w;
-    GetRootWidget(getter_AddRefs(w));
-    if (w) {
-      w->Update();
-    }
-  }
 }
 
 void

view/nsViewManager.h

@@ -303,16 +303,11 @@ public:
    */
   static nsView* GetDisplayRootFor(nsView* aView);
 
-  enum UpdatingMode {
-    eNoSyncUpdate,
-    eTrySyncUpdate
-  };
-
   /**
    * Flush the accumulated dirty region to the widget and update widget
    * geometry.
    */
-  void ProcessPendingUpdates(UpdatingMode aMode);
+  void ProcessPendingUpdates();
 
   /**
    * Just update widget geometry without flushing the dirty region

widget/gtk/nsWindow.cpp

@@ -1697,14 +1697,6 @@ nsWindow::Invalidate(const nsIntRect &aRect)
     return NS_OK;
 }
 
-void
-nsWindow::Update()
-{
-    if (!ShouldUseOffMainThreadCompositing() && mGdkWindow) {
-        gdk_window_process_updates(mGdkWindow, true);
-    }
-}
-
 void*
 nsWindow::GetNativeData(uint32_t aDataType)
 {

widget/gtk/nsWindow.h

@@ -133,7 +133,6 @@ public:
     NS_IMETHOD         SetCursor(imgIContainer* aCursor,
                                  uint32_t aHotspotX, uint32_t aHotspotY) override;
     NS_IMETHOD         Invalidate(const nsIntRect &aRect) override;
-    virtual void       Update() override;
     virtual void*      GetNativeData(uint32_t aDataType) override;
     void               SetNativeData(uint32_t aDataType, uintptr_t aVal) override;
     NS_IMETHOD         SetTitle(const nsAString& aTitle) override;

widget/nsBaseAppShell.cpp

@@ -25,7 +25,11 @@ nsBaseAppShell::nsBaseAppShell()
   : mSuspendNativeCount(0)
   , mEventloopNestingLevel(0)
   , mBlockedWait(nullptr)
+  , mFavorPerf(0)
   , mNativeEventPending(false)
+  , mStarvationDelay(0)
+  , mSwitchTime(0)
+  , mLastNativeEventTime(0)
   , mEventloopNestingState(eEventloopNone)
   , mRunning(false)
   , mExiting(false)
@@ -175,6 +179,20 @@ nsBaseAppShell::Exit(void)
   return NS_OK;
 }
 
+NS_IMETHODIMP
+nsBaseAppShell::FavorPerformanceHint(bool favorPerfOverStarvation,
+                                     uint32_t starvationDelay)
+{
+  mStarvationDelay = PR_MillisecondsToInterval(starvationDelay);
+  if (favorPerfOverStarvation) {
+    ++mFavorPerf;
+  } else {
+    --mFavorPerf;
+    mSwitchTime = PR_IntervalNow();
+  }
+  return NS_OK;
+}
+
 NS_IMETHODIMP
 nsBaseAppShell::SuspendNative()
 {
@@ -235,6 +253,9 @@ nsBaseAppShell::OnProcessNextEvent(nsIThreadInternal *thr, bool mayWait,
       OnDispatchedEvent(thr); // in case we blocked it earlier
   }
 
+  PRIntervalTime start = PR_IntervalNow();
+  PRIntervalTime limit = THREAD_EVENT_STARVATION_LIMIT;
+
   // Unblock outer nested wait loop (below).
   if (mBlockedWait)
     *mBlockedWait = false;
@@ -250,7 +271,21 @@ nsBaseAppShell::OnProcessNextEvent(nsIThreadInternal *thr, bool mayWait,
   // NativeEventCallback to process gecko events.
   mProcessedGeckoEvents = false;
 
-  DoProcessNextNativeEvent(false, recursionDepth);
+  if (mFavorPerf <= 0 && start > mSwitchTime + mStarvationDelay) {
+    // Favor pending native events
+    PRIntervalTime now = start;
+    bool keepGoing;
+    do {
+      mLastNativeEventTime = now;
+      keepGoing = DoProcessNextNativeEvent(false, recursionDepth);
+    } while (keepGoing && ((now = PR_IntervalNow()) - start) < limit);
+  } else {
+    // Avoid starving native events completely when in performance mode
+    if (start - mLastNativeEventTime > limit) {
+      mLastNativeEventTime = start;
+      DoProcessNextNativeEvent(false, recursionDepth);
+    }
+  }
 
   while (!NS_HasPendingEvents(thr) && !mProcessedGeckoEvents) {
     // If we have been asked to exit from Run, then we should not wait for
@@ -259,6 +294,7 @@ nsBaseAppShell::OnProcessNextEvent(nsIThreadInternal *thr, bool mayWait,
     if (mExiting)
       mayWait = false;
 
+    mLastNativeEventTime = PR_IntervalNow();
     if (!DoProcessNextNativeEvent(mayWait, recursionDepth) || !mayWait)
       break;
   }

widget/nsBaseAppShell.h

@@ -122,7 +122,11 @@ private:
    * have been consumed by the inner event loop(s).
    */
   bool *mBlockedWait;
+  int32_t mFavorPerf;
   mozilla::Atomic<bool> mNativeEventPending;
+  PRIntervalTime mStarvationDelay;
+  PRIntervalTime mSwitchTime;
+  PRIntervalTime mLastNativeEventTime;
   enum EventloopNestingState {
     eEventloopNone,  // top level thread execution
     eEventloopXPCOM, // innermost native event loop is ProcessNextNativeEvent

widget/nsIAppShell.idl

@@ -12,7 +12,7 @@ interface nsIRunnable;
  * Interface for the native event system layer.  This interface is designed
  * to be used on the main application thread only.
  */
-[uuid(78dc2b13-5de6-42f3-af57-2535f7fdb93e)]
+[uuid(2d10ca53-f143-439a-bb2e-c1fbc71f6a05)]
 interface nsIAppShell : nsISupports
 {
   /**
@@ -25,6 +25,24 @@ interface nsIAppShell : nsISupports
    */
   void exit();
 
+  /**
+   * Give hint to native event queue notification mechanism. If the native
+   * platform needs to tradeoff performance vs. native event starvation this
+   * hint tells the native dispatch code which to favor.  The default is to
+   * prevent native event starvation.
+   *
+   * Calls to this function may be nested. When the number of calls that pass
+   * PR_TRUE is subtracted from the number of calls that pass PR_FALSE is
+   * greater than 0, performance is given precedence over preventing event
+   * starvation.
+   *
+   * The starvationDelay arg is only used when favorPerfOverStarvation is
+   * PR_FALSE. It is the amount of time in milliseconds to wait before the
+   * PR_FALSE actually takes effect.
+   */
+  void favorPerformanceHint(in boolean favorPerfOverStarvation,
+                            in unsigned long starvationDelay);
+
   /**
    * Suspends the use of additional platform-specific methods (besides the
    * nsIAppShell->run() event loop) to run Gecko events on the main

widget/nsIWidget.h

@@ -114,8 +114,8 @@ typedef void* nsNativeWidget;
 #define NS_NATIVE_PLUGIN_ID            105
 
 #define NS_IWIDGET_IID \
-{ 0x7a4ece50, 0x5c52, 0x47c2, \
-  { 0x8c, 0x9e, 0x32, 0xd2, 0x5a, 0x27, 0x53, 0x34 } }
+{ 0x316E4600, 0x15DB, 0x47AE, \
+  { 0xBF, 0xE4, 0x5B, 0xCD, 0xFF, 0x80, 0x80, 0x83 } };
 
 /*
  * Window shadow styles
@@ -1503,11 +1503,6 @@ class nsIWidget : public nsISupports {
      */
     NS_IMETHOD Invalidate(const nsIntRect & aRect) = 0;
 
-    /**
-     * Widget implementation may support synchronous painting.
-     */
-   virtual void Update() { }
-
     enum LayerManagerPersistence
     {
       LAYER_MANAGER_CURRENT = 0,

widget/windows/nsWindow.cpp

@@ -2826,14 +2826,6 @@ NS_METHOD nsWindow::Invalidate(const nsIntRect & aRect)
   return NS_OK;
 }
 
-void
-nsWindow::Update()
-{
-  if (!ShouldUseOffMainThreadCompositing() && mWnd) {
-    ::UpdateWindow(mWnd);
-  }
-}
-
 NS_IMETHODIMP
 nsWindow::MakeFullScreen(bool aFullScreen, nsIScreen* aTargetScreen)
 {

widget/windows/nsWindow.h

@@ -134,7 +134,6 @@ public:
                                      bool aUpdateNCArea = false,
                                      bool aIncludeChildren = false);
   NS_IMETHOD              Invalidate(const nsIntRect & aRect);
-  virtual void            Update() override;
   virtual void*           GetNativeData(uint32_t aDataType);
   virtual void            FreeNativeData(void * data, uint32_t aDataType);
   NS_IMETHOD              SetTitle(const nsAString& aTitle);

widget/windows/winrt/MetroWidget.cpp

@@ -1182,14 +1182,6 @@ MetroWidget::Invalidate(bool aEraseBackground,
   return NS_OK;
 }
 
-void
-MetroWidget::Update()
-{
-  if (!ShouldUseOffMainThreadCompositing() && mWnd) {
-    ::UpdateWindow(mWnd);
-  }
-}
-
 NS_IMETHODIMP
 MetroWidget::Invalidate(const nsIntRect & aRect)
 {

widget/windows/winrt/MetroWidget.h

@@ -110,7 +110,6 @@ public:
                 bool aUpdateNCArea = false,
                 bool aIncludeChildren = false);
   NS_IMETHOD    Invalidate(const nsIntRect & aRect);
-  virtual void  Update() override;
   NS_IMETHOD    DispatchEvent(mozilla::WidgetGUIEvent* aEvent,
                               nsEventStatus& aStatus);
   NS_IMETHOD    ConstrainPosition(bool aAllowSlop, int32_t *aX, int32_t *aY);