Bug 1074401 - Ensure that the repaint request is always dispatched from the APZ on the main thread. r=botond

gfx/layers/apz/public/GeckoContentController.h

@@ -25,6 +25,7 @@ public:
   /**
    * Requests a paint of the given FrameMetrics |aFrameMetrics| from Gecko.
    * Implementations per-platform are responsible for actually handling this.
+   * This method will always be called on the Gecko main thread.
    */
   virtual void RequestContentRepaint(const FrameMetrics& aFrameMetrics) = 0;
 

gfx/layers/apz/src/AsyncPanZoomController.cpp

@@ -2403,7 +2403,12 @@ AsyncPanZoomController::DispatchRepaintRequest(const FrameMetrics& aFrameMetrics
     APZC_LOG_FM(aFrameMetrics, "%p requesting content repaint", this);
     LogRendertraceRect(GetGuid(), "requested displayport", "yellow", GetDisplayPortRect(aFrameMetrics));
 
-    controller->RequestContentRepaint(aFrameMetrics);
+    if (NS_IsMainThread()) {
+      controller->RequestContentRepaint(aFrameMetrics);
+    } else {
+      NS_DispatchToMainThread(NS_NewRunnableMethodWithArg<FrameMetrics>(
+        controller, &GeckoContentController::RequestContentRepaint, aFrameMetrics));
+    }
     mLastDispatchedPaintMetrics = aFrameMetrics;
   }
 }

layout/ipc/RenderFrameParent.cpp

@@ -86,12 +86,11 @@ public:
 
   virtual void RequestContentRepaint(const FrameMetrics& aFrameMetrics) MOZ_OVERRIDE
   {
-    // We always need to post requests into the "UI thread" otherwise the
-    // requests may get processed out of order.
-    mUILoop->PostTask(
-      FROM_HERE,
-      NewRunnableMethod(this, &RemoteContentController::DoRequestContentRepaint,
-                        aFrameMetrics));
+    MOZ_ASSERT(NS_IsMainThread());
+    if (mRenderFrame) {
+      TabParent* browser = static_cast<TabParent*>(mRenderFrame->Manager());
+      browser->UpdateFrame(aFrameMetrics);
+    }
   }
 
   virtual void AcknowledgeScrollUpdate(const FrameMetrics::ViewID& aScrollId,
@@ -261,14 +260,6 @@ public:
     mTouchSensitiveRegion = aRegion;
   }
 private:
-  void DoRequestContentRepaint(const FrameMetrics& aFrameMetrics)
-  {
-    if (mRenderFrame) {
-      TabParent* browser = static_cast<TabParent*>(mRenderFrame->Manager());
-      browser->UpdateFrame(aFrameMetrics);
-    }
-  }
-
   MessageLoop* mUILoop;
   RenderFrameParent* mRenderFrame;
 

widget/android/APZCCallbackHandler.cpp

@@ -82,12 +82,6 @@ APZCCallbackHandler::GetDOMWindowUtils()
 void
 APZCCallbackHandler::RequestContentRepaint(const FrameMetrics& aFrameMetrics)
 {
-    if (!NS_IsMainThread()) {
-        NS_DispatchToMainThread(NS_NewRunnableMethodWithArg<FrameMetrics>(
-            this, &APZCCallbackHandler::RequestContentRepaint, aFrameMetrics));
-        return;
-    }
-
     MOZ_ASSERT(NS_IsMainThread());
     MOZ_ASSERT(aFrameMetrics.GetScrollId() != FrameMetrics::NULL_SCROLL_ID);
 

widget/cocoa/nsChildView.mm

@@ -402,38 +402,16 @@ class APZCTMController : public mozilla::layers::GeckoContentController
   typedef mozilla::layers::FrameMetrics FrameMetrics;
   typedef mozilla::layers::ScrollableLayerGuid ScrollableLayerGuid;
 
-  class RequestContentRepaintEvent : public nsRunnable
-  {
-  public:
-    explicit RequestContentRepaintEvent(const FrameMetrics& aFrameMetrics)
-      : mFrameMetrics(aFrameMetrics)
-    {
-    }
-
-    NS_IMETHOD Run()
-    {
-      MOZ_ASSERT(NS_IsMainThread());
-
-      nsCOMPtr<nsIContent> targetContent = nsLayoutUtils::FindContentFor(mFrameMetrics.GetScrollId());
-      if (targetContent) {
-        APZCCallbackHelper::UpdateSubFrame(targetContent, mFrameMetrics);
-      }
-
-      return NS_OK;
-    }
-  protected:
-    FrameMetrics mFrameMetrics;
-  };
-
 public:
   // GeckoContentController interface
   virtual void RequestContentRepaint(const FrameMetrics& aFrameMetrics)
   {
-    nsCOMPtr<nsIRunnable> r1 = new RequestContentRepaintEvent(aFrameMetrics);
-    if (!NS_IsMainThread()) {
-      NS_DispatchToMainThread(r1);
-    } else {
-      r1->Run();
+    MOZ_ASSERT(NS_IsMainThread());
+
+    nsCOMPtr<nsIContent> targetContent = nsLayoutUtils::FindContentFor(aFrameMetrics.GetScrollId());
+    if (targetContent) {
+      FrameMetrics metrics = aFrameMetrics;
+      APZCCallbackHelper::UpdateSubFrame(targetContent, metrics);
     }
   }
 

widget/gonk/ParentProcessController.cpp

@@ -12,41 +12,19 @@
 namespace mozilla {
 namespace widget {
 
-class RequestContentRepaintEvent : public nsRunnable
-{
-    typedef mozilla::layers::FrameMetrics FrameMetrics;
-
-public:
-    RequestContentRepaintEvent(const FrameMetrics& aFrameMetrics)
-        : mFrameMetrics(aFrameMetrics)
-    {
-    }
-
-    NS_IMETHOD Run() {
-        MOZ_ASSERT(NS_IsMainThread());
-        nsCOMPtr<nsIContent> content = nsLayoutUtils::FindContentFor(mFrameMetrics.GetScrollId());
-        if (content) {
-            mozilla::layers::APZCCallbackHelper::UpdateSubFrame(content, mFrameMetrics);
-        }
-        return NS_OK;
-    }
-
-protected:
-    FrameMetrics mFrameMetrics;
-};
-
 void
 ParentProcessController::RequestContentRepaint(const FrameMetrics& aFrameMetrics)
 {
+    MOZ_ASSERT(NS_IsMainThread());
+
     if (aFrameMetrics.GetScrollId() == FrameMetrics::NULL_SCROLL_ID) {
         return;
     }
 
-    nsCOMPtr<nsIRunnable> r = new RequestContentRepaintEvent(aFrameMetrics);
-    if (!NS_IsMainThread()) {
-        NS_DispatchToMainThread(r);
-    } else {
-        r->Run();
+    nsCOMPtr<nsIContent> content = nsLayoutUtils::FindContentFor(aFrameMetrics.GetScrollId());
+    if (content) {
+        FrameMetrics metrics = aFrameMetrics;
+        mozilla::layers::APZCCallbackHelper::UpdateSubFrame(content, metrics);
     }
 }
 

widget/windows/winrt/APZController.cpp

@@ -79,70 +79,6 @@ GetDOMTargets(uint64_t aScrollId,
   return true;
 }
 
-class RequestContentRepaintEvent : public nsRunnable
-{
-  typedef mozilla::layers::FrameMetrics FrameMetrics;
-
-public:
-  RequestContentRepaintEvent(const FrameMetrics& aFrameMetrics) :
-    mFrameMetrics(aFrameMetrics)
-  {
-  }
-
-  NS_IMETHOD Run() {
-    // This must be on the gecko thread since we access the dom
-    MOZ_ASSERT(NS_IsMainThread());
-
-#ifdef DEBUG_CONTROLLER
-    WinUtils::Log("APZController: mScrollOffset: %f %f", mFrameMetrics.mScrollOffset.x,
-      mFrameMetrics.mScrollOffset.y);
-#endif
-
-    nsCOMPtr<nsIDocument> subDocument;
-    nsCOMPtr<nsIContent> targetContent;
-    if (!GetDOMTargets(mFrameMetrics.GetScrollId(),
-                       subDocument, targetContent)) {
-      return NS_OK;
-    }
-
-    // If we're dealing with a sub frame or content editable element,
-    // call UpdateSubFrame.
-    if (targetContent) {
-#ifdef DEBUG_CONTROLLER
-      WinUtils::Log("APZController: detected subframe or content editable");
-#endif
-      mozilla::layers::APZCCallbackHelper::UpdateSubFrame(targetContent, mFrameMetrics);
-      return NS_OK;
-    }
-
-#ifdef DEBUG_CONTROLLER
-    WinUtils::Log("APZController: detected tab");
-#endif
-
-    // We're dealing with a tab, call UpdateRootFrame.
-    nsCOMPtr<nsIDOMWindowUtils> utils;
-    nsCOMPtr<nsIDOMWindow> window = subDocument->GetDefaultView();
-    if (window) {
-      utils = do_GetInterface(window);
-      if (utils) {
-        mozilla::layers::APZCCallbackHelper::UpdateRootFrame(utils, mFrameMetrics);
-
-#ifdef DEBUG_CONTROLLER
-        WinUtils::Log("APZController: %I64d mDisplayPortMargins: %0.2f %0.2f %0.2f %0.2f",
-          mFrameMetrics.GetScrollId(),
-          mFrameMetrics.GetDisplayPortMargins().left,
-          mFrameMetrics.GetDisplayPortMargins().top,
-          mFrameMetrics.GetDisplayPortMargins().right,
-          mFrameMetrics.GetDisplayPortMargins().bottom);
-#endif
-      }
-    }
-    return NS_OK;
-  }
-protected:
-  FrameMetrics mFrameMetrics;
-};
-
 void
 APZController::SetPendingResponseFlusher(APZPendingResponseFlusher* aFlusher)
 {
@@ -198,11 +134,55 @@ APZController::RequestContentRepaint(const FrameMetrics& aFrameMetrics)
   WinUtils::Log("APZController::RequestContentRepaint scrollid=%I64d",
     aFrameMetrics.GetScrollId());
 #endif
-  nsCOMPtr<nsIRunnable> r1 = new RequestContentRepaintEvent(aFrameMetrics);
-  if (!NS_IsMainThread()) {
-    NS_DispatchToMainThread(r1);
-  } else {
-    r1->Run();
+
+  // This must be on the gecko thread since we access the dom
+  MOZ_ASSERT(NS_IsMainThread());
+
+#ifdef DEBUG_CONTROLLER
+  WinUtils::Log("APZController: mScrollOffset: %f %f", aFrameMetrics.mScrollOffset.x,
+    aFrameMetrics.mScrollOffset.y);
+#endif
+
+  nsCOMPtr<nsIDocument> subDocument;
+  nsCOMPtr<nsIContent> targetContent;
+  if (!GetDOMTargets(aFrameMetrics.GetScrollId(),
+                     subDocument, targetContent)) {
+    return NS_OK;
+  }
+
+  // If we're dealing with a sub frame or content editable element,
+  // call UpdateSubFrame.
+  if (targetContent) {
+#ifdef DEBUG_CONTROLLER
+    WinUtils::Log("APZController: detected subframe or content editable");
+#endif
+    FrameMetrics metrics = aFrameMetrics;
+    mozilla::layers::APZCCallbackHelper::UpdateSubFrame(targetContent, metrics);
+    return NS_OK;
+  }
+
+#ifdef DEBUG_CONTROLLER
+  WinUtils::Log("APZController: detected tab");
+#endif
+
+  // We're dealing with a tab, call UpdateRootFrame.
+  nsCOMPtr<nsIDOMWindowUtils> utils;
+  nsCOMPtr<nsIDOMWindow> window = subDocument->GetDefaultView();
+  if (window) {
+    utils = do_GetInterface(window);
+    if (utils) {
+      FrameMetrics metrics = aFrameMetrics;
+      mozilla::layers::APZCCallbackHelper::UpdateRootFrame(utils, metrics);
+
+#ifdef DEBUG_CONTROLLER
+      WinUtils::Log("APZController: %I64d mDisplayPortMargins: %0.2f %0.2f %0.2f %0.2f",
+        metrics.GetScrollId(),
+        metrics.GetDisplayPortMargins().left,
+        metrics.GetDisplayPortMargins().top,
+        metrics.GetDisplayPortMargins().right,
+        metrics.GetDisplayPortMargins().bottom);
+#endif
+    }
   }
 }