Instrument some of the exit paths likely to suffer hangs.

chrome/browser/lifetime/application_lifetime.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/browser/lifetime/application_lifetime.h"
 
 #include "ash/shell.h"
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "base/debug/trace_event.h"
@@ skipping 30 matching lines @@
 #if defined(OS_CHROMEOS)
 #include "base/sys_info.h"
 #include "chrome/browser/chromeos/boot_times_loader.h"
 #include "chromeos/dbus/dbus_thread_manager.h"
 #include "chromeos/dbus/session_manager_client.h"
 #include "chromeos/dbus/update_engine_client.h"
 #endif
 
 #if defined(OS_WIN)
 #include "base/win/win_util.h"
+#include "components/browser_watcher/exit_funnel.h"
 #endif
 
 namespace chrome {
 namespace {
 
 #if !defined(OS_ANDROID)
 // Returns true if all browsers can be closed without user interaction.
 // This currently checks if there is pending download, or if it needs to
 // handle unload handler.
 bool AreAllBrowsersCloseable() {
@@ skipping 183 matching lines @@
   // screen locker.
   if (!AreAllBrowsersCloseable())
     browser_shutdown::OnShutdownStarting(browser_shutdown::END_SESSION);
   else
     browser_shutdown::OnShutdownStarting(browser_shutdown::BROWSER_EXIT);
   AttemptExitInternal(true);
 }
 #endif
 
 void SessionEnding() {
+#if defined(OS_WIN)
+  browser_watcher::ExitFunnel funnel(kBrowserExitCodesRegistryPath,
+                                     base::GetCurrentProcessHandle());
+  funnel.RecordEvent(L"SessionEnding");
+#endif
   // This is a time-limited shutdown where we need to write as much to
   // disk as we can as soon as we can, and where we must kill the
   // process within a hang timeout to avoid user prompts.
 
   // Start watching for hang during shutdown, and crash it if takes too long.
   // We disarm when |shutdown_watcher| object is destroyed, which is when we
   // exit this function.
   ShutdownWatcherHelper shutdown_watcher;
   shutdown_watcher.Arm(base::TimeDelta::FromSeconds(90));
 
   // EndSession is invoked once per frame. Only do something the first time.
   static bool already_ended = false;
   // We may get called in the middle of shutdown, e.g. http://crbug.com/70852
   // In this case, do nothing.
   if (already_ended || !content::NotificationService::current())
     return;
   already_ended = true;
 
   browser_shutdown::OnShutdownStarting(browser_shutdown::END_SESSION);
 
   content::NotificationService::current()->Notify(
       chrome::NOTIFICATION_CLOSE_ALL_BROWSERS_REQUEST,
       content::NotificationService::AllSources(),
       content::NotificationService::NoDetails());
 
+#if defined(OS_WIN)
+  funnel.RecordEvent(L"EndSession");
+#endif
   // Write important data first.
   g_browser_process->EndSession();
 
 #if defined(OS_WIN)
   base::win::SetShouldCrashOnProcessDetach(false);
 #endif
 
+#if defined(OS_WIN)
+  // KillProcess ought to terminate the process without further ado, so if
+  // execution gets to this point, presumably this is normal exit.
+  funnel.RecordEvent(L"KillProcess");
+#endif
+
   // On Windows 7 and later, the system will consider the process ripe for
   // termination as soon as it hides or destroys its windows. Since any
   // execution past that point will be non-deterministically cut short, we
   // might as well put ourselves out of that misery deterministically.
   base::KillProcess(base::GetCurrentProcessHandle(), 0, false);
 }
 
 void IncrementKeepAliveCount() {
   // Increment the browser process refcount as long as we're keeping the
   // application alive.
@@ skipping 99 matching lines @@
   //    environment is still active.
   if (browser->host_desktop_type() == chrome::HOST_DESKTOP_TYPE_NATIVE)
     return !ash::Shell::HasInstance();
   else if (browser->host_desktop_type() == chrome::HOST_DESKTOP_TYPE_ASH)
     return BrowserList::GetInstance(chrome::HOST_DESKTOP_TYPE_NATIVE)->empty();
 #endif
   return true;
 }
 
 }  // namespace chrome