bug 606574 - Win32 event loop instrumentation. r=jimm

configure.in

@@ -5203,6 +5203,7 @@ cairo-windows)
         ;;
     esac
     MOZ_PDF_PRINTING=1
+    MOZ_INSTRUMENT_EVENT_LOOP=1
     ;;
 
 cairo-gtk2|cairo-gtk2-x11)

widget/public/WidgetTraceEvent.h

@@ -45,6 +45,9 @@ namespace mozilla {
 // a thread that's not the UI thread.
 bool FireAndWaitForTracerEvent();
 
+// Signal that the event has been received by the event loop.
+void SignalTracerThread();
+
 }
 
 #endif  // WIDGET_PUBLIC_WIDGETTRACEEVENT_H_

widget/src/windows/Makefile.in

@@ -47,32 +47,33 @@ LIBRARY_NAME	= widget_windows
 LIBXUL_LIBRARY = 1
 
 
-CPPSRCS		= \
-	nsWindow.cpp \
-	nsWindowGfx.cpp \
-	nsWindowDbg.cpp \
-	nsAppShell.cpp \
-	nsToolkit.cpp \
-	nsFilePicker.cpp \
-	nsScreenWin.cpp	\
-	nsScreenManagerWin.cpp \
-	nsLookAndFeel.cpp \
-	nsUXThemeData.cpp \
-	nsNativeThemeWin.cpp \
-	nsWinGesture.cpp \
-	nsIdleServiceWin.cpp \
-	nsSound.cpp \
-	nsIMM32Handler.cpp \
-	WindowHook.cpp \
-	WinTaskbar.cpp \
-	TaskbarPreview.cpp \
-	TaskbarTabPreview.cpp \
-	TaskbarWindowPreview.cpp \
-	TaskbarPreviewButton.cpp \
- 	JumpListBuilder.cpp \
- 	JumpListItem.cpp \
-	GfxInfo.cpp \
-	$(NULL)
+CPPSRCS = \
+  nsWindow.cpp \
+  nsWindowGfx.cpp \
+  nsWindowDbg.cpp \
+  nsAppShell.cpp \
+  nsToolkit.cpp \
+  nsFilePicker.cpp \
+  nsScreenWin.cpp  \
+  nsScreenManagerWin.cpp \
+  nsLookAndFeel.cpp \
+  nsUXThemeData.cpp \
+  nsNativeThemeWin.cpp \
+  nsWinGesture.cpp \
+  nsIdleServiceWin.cpp \
+  nsSound.cpp \
+  nsIMM32Handler.cpp \
+  WindowHook.cpp \
+  WinTaskbar.cpp \
+  TaskbarPreview.cpp \
+  TaskbarTabPreview.cpp \
+  TaskbarWindowPreview.cpp \
+  TaskbarPreviewButton.cpp \
+  JumpListBuilder.cpp \
+  JumpListItem.cpp \
+  GfxInfo.cpp \
+  WidgetTraceEvent.cpp \
+  $(NULL)
 
 ifdef MOZ_CRASHREPORTER
 CPPSRCS += LSPAnnotator.cpp

widget/src/windows/WidgetTraceEvent.cpp

@@ -0,0 +1,148 @@
+/* ***** BEGIN LICENSE BLOCK *****
+ * Version: MPL 1.1/GPL 2.0/LGPL 2.1
+ *
+ * The contents of this file are subject to the Mozilla Public License Version
+ * 1.1 (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ * http://www.mozilla.org/MPL/
+ *
+ * Software distributed under the License is distributed on an "AS IS" basis,
+ * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
+ * for the specific language governing rights and limitations under the
+ * License.
+ *
+ * The Original Code is mozilla.org code.
+ *
+ * The Initial Developer of the Original Code is
+ * The Mozilla Foundation.
+ * Portions created by the Initial Developer are Copyright (C) 2011
+ * the Initial Developer. All Rights Reserved.
+ *
+ * Contributor(s):
+ *   Ted Mielczarek <ted.mielczarek@gmail.com>
+ *
+ * Alternatively, the contents of this file may be used under the terms of
+ * either the GNU General Public License Version 2 or later (the "GPL"), or
+ * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
+ * in which case the provisions of the GPL or the LGPL are applicable instead
+ * of those above. If you wish to allow use of your version of this file only
+ * under the terms of either the GPL or the LGPL, and not to allow others to
+ * use your version of this file under the terms of the MPL, indicate your
+ * decision by deleting the provisions above and replace them with the notice
+ * and other provisions required by the GPL or the LGPL. If you do not delete
+ * the provisions above, a recipient may use your version of this file under
+ * the terms of any one of the MPL, the GPL or the LGPL.
+ *
+ * ***** END LICENSE BLOCK ***** */
+
+/*
+ * Windows widget support for event loop instrumentation.
+ * See toolkit/xre/EventTracer.cpp for more details.
+ */
+
+#include <stdio.h>
+#include <windows.h>
+
+#include "mozilla/WidgetTraceEvent.h"
+#include "nsAppShellCID.h"
+#include "nsComponentManagerUtils.h"
+#include "nsCOMPtr.h"
+#include "nsIAppShellService.h"
+#include "nsIBaseWindow.h"
+#include "nsIDocShell.h"
+#include "nsIWidget.h"
+#include "nsIXULWindow.h"
+#include "nsAutoPtr.h"
+#include "nsServiceManagerUtils.h"
+#include "nsThreadUtils.h"
+#include "nsWindowDefs.h"
+
+namespace {
+
+// Used for signaling the background thread from the main thread.
+HANDLE event_handle = NULL;
+
+// We need a runnable in order to find the hidden window on the main
+// thread.
+class HWNDGetter : public nsRunnable {
+public:
+  HWNDGetter() : hidden_window_hwnd(NULL) {}
+
+  HWND hidden_window_hwnd;
+
+  NS_IMETHOD Run() {
+    // Jump through some hoops to locate the hidden window.
+    nsCOMPtr<nsIAppShellService> appShell(do_GetService(NS_APPSHELLSERVICE_CONTRACTID));
+    nsCOMPtr<nsIXULWindow> hiddenWindow;
+
+    nsresult rv = appShell->GetHiddenWindow(getter_AddRefs(hiddenWindow));
+    if (NS_FAILED(rv)) {
+      return rv;
+    }
+
+    nsCOMPtr<nsIDocShell> docShell;
+    rv = hiddenWindow->GetDocShell(getter_AddRefs(docShell));
+    if (NS_FAILED(rv) || !docShell) {
+      return rv;
+    }
+
+    nsCOMPtr<nsIBaseWindow> baseWindow(do_QueryInterface(docShell));
+    
+    if (!baseWindow)
+      return NS_ERROR_FAILURE;
+
+    nsCOMPtr<nsIWidget> widget;
+    baseWindow->GetMainWidget(getter_AddRefs(widget));
+
+    if (!widget)
+      return NS_ERROR_FAILURE;
+
+    hidden_window_hwnd = (HWND)widget->GetNativeData(NS_NATIVE_WINDOW);
+
+    return NS_OK;
+  }
+};
+
+HWND GetHiddenWindowHWND()
+{
+  // Need to dispatch this to the main thread because plenty of
+  // the things it wants to access are main-thread-only.
+  nsRefPtr<HWNDGetter> getter = new HWNDGetter();
+  NS_DispatchToMainThread(getter, NS_DISPATCH_SYNC);
+  return getter->hidden_window_hwnd;
+}
+
+} // namespace
+
+namespace mozilla {
+
+// This function is called from the main (UI) thread.
+void SignalTracerThread()
+{
+  if (event_handle != NULL)
+    SetEvent(event_handle);
+}
+
+// This function is called from the background tracer thread.
+bool FireAndWaitForTracerEvent()
+{
+  // First, try to find the hidden window.
+  static HWND hidden_window = NULL;
+  if (hidden_window == NULL) {
+    hidden_window = GetHiddenWindowHWND();
+  }
+
+  if (hidden_window == NULL)
+    return false;
+
+  if (event_handle == NULL)
+    event_handle = CreateEvent(NULL, FALSE, FALSE, NULL);
+
+  // Post the tracer message into the hidden window's message queue,
+  // and then block until it's processed.
+  PostMessage(hidden_window, MOZ_WM_TRACE, 0, 0);
+  WaitForSingleObject(event_handle, INFINITE);
+  return true;
+}
+
+}  // namespace mozilla

widget/src/windows/nsWindow.cpp

@@ -118,6 +118,7 @@
 #include "prprf.h"
 #include "prmem.h"
 
+#include "mozilla/WidgetTraceEvent.h"
 #include "nsIAppShell.h"
 #include "nsISupportsPrimitives.h"
 #include "nsIDOMNSUIEvent.h"
@@ -4596,6 +4597,13 @@ LRESULT CALLBACK nsWindow::WindowProcInternal(HWND hWnd, UINT msg, WPARAM wParam
     }
   }
 
+  if (msg == MOZ_WM_TRACE) {
+    // This is a tracer event for measuring event loop latency.
+    // See WidgetTraceEvent.cpp for more details.
+    mozilla::SignalTracerThread();
+    return 0;
+  }
+
   // Get the window which caused the event and ask it to process the message
   nsWindow *someWindow = GetNSWindowPtr(hWnd);
 

widget/src/windows/nsWindowDefs.h

@@ -56,6 +56,8 @@
 // A magic APP message that can be sent to quit, sort of like a QUERYENDSESSION/ENDSESSION,
 // but without the query.
 #define MOZ_WM_APP_QUIT                   (WM_APP+0x0300)
+// Used as a "tracer" event to probe event loop latency.
+#define MOZ_WM_TRACE                      (WM_APP+0x0301)
 
 // GetWindowsVersion constants
 #define WIN2K_VERSION                     0x500