1 files changed, 118 insertions, 0 deletions
diff --git a/tools/profiler/gecko/ThreadResponsiveness.cpp b/tools/profiler/gecko/ThreadResponsiveness.cpp
new file mode 100644
index 000000000..0057251e2
--- /dev/null
+++ b/tools/profiler/gecko/ThreadResponsiveness.cpp
@@ -0,0 +1,118 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "ThreadResponsiveness.h"
+#include "platform.h"
+#include "nsComponentManagerUtils.h"
+#include "nsThreadUtils.h"
+#include "nsITimer.h"
+#include "mozilla/Monitor.h"
+#include "ProfileEntry.h"
+#include "ThreadProfile.h"
+
+using mozilla::Monitor;
+using mozilla::MonitorAutoLock;
+using mozilla::TimeStamp;
+
+class CheckResponsivenessTask : public mozilla::Runnable,
+                                public nsITimerCallback {
+public:
+  CheckResponsivenessTask()
+    : mLastTracerTime(TimeStamp::Now())
+    , mMonitor("CheckResponsivenessTask")
+    , mTimer(nullptr)
+    , mStop(false)
+  {
+    MOZ_COUNT_CTOR(CheckResponsivenessTask);
+  }
+
+protected:
+  ~CheckResponsivenessTask()
+  {
+    MOZ_COUNT_DTOR(CheckResponsivenessTask);
+  }
+
+public:
+  NS_IMETHOD Run() override
+  {
+    MonitorAutoLock mon(mMonitor);
+    if (mStop)
+      return NS_OK;
+
+    // This is raced on because we might pause the thread here
+    // for profiling so if we tried to use a monitor to protect
+    // mLastTracerTime we could deadlock. We're risking seeing
+    // a partial write which will show up as an outlier in our
+    // performance data.
+    mLastTracerTime = TimeStamp::Now();
+    if (!mTimer) {
+      mTimer = do_CreateInstance("@mozilla.org/timer;1");
+    }
+    mTimer->InitWithCallback(this, 16, nsITimer::TYPE_ONE_SHOT);
+
+    return NS_OK;
+  }
+
+  NS_IMETHOD Notify(nsITimer* aTimer) final
+  {
+    NS_DispatchToMainThread(this);
+    return NS_OK;
+  }
+
+  void Terminate() {
+    MonitorAutoLock mon(mMonitor);
+    mStop = true;
+  }
+
+  const TimeStamp& GetLastTracerTime() const {
+    return mLastTracerTime;
+  }
+
+  NS_DECL_ISUPPORTS_INHERITED
+
+private:
+  TimeStamp mLastTracerTime;
+  Monitor mMonitor;
+  nsCOMPtr<nsITimer> mTimer;
+  bool mStop;
+};
+
+NS_IMPL_ISUPPORTS_INHERITED(CheckResponsivenessTask, mozilla::Runnable,
+                            nsITimerCallback)
+
+ThreadResponsiveness::ThreadResponsiveness(ThreadProfile *aThreadProfile)
+  : mThreadProfile(aThreadProfile)
+  , mActiveTracerEvent(nullptr)
+{
+  MOZ_COUNT_CTOR(ThreadResponsiveness);
+}
+
+ThreadResponsiveness::~ThreadResponsiveness()
+{
+  MOZ_COUNT_DTOR(ThreadResponsiveness);
+  if (mActiveTracerEvent) {
+    mActiveTracerEvent->Terminate();
+  }
+}
+
+void
+ThreadResponsiveness::Update()
+{
+  if (!mActiveTracerEvent) {
+    if (mThreadProfile->GetThreadInfo()->IsMainThread()) {
+      mActiveTracerEvent = new CheckResponsivenessTask();
+      NS_DispatchToMainThread(mActiveTracerEvent);
+    } else if (mThreadProfile->GetThreadInfo()->GetThread()) {
+      mActiveTracerEvent = new CheckResponsivenessTask();
+      mThreadProfile->GetThreadInfo()->
+        GetThread()->Dispatch(mActiveTracerEvent, NS_DISPATCH_NORMAL);
+    }
+  }
+
+  if (mActiveTracerEvent) {
+    mLastTracerTime = mActiveTracerEvent->GetLastTracerTime();
+  }
+}
+