Support tracking of IPC messages as tasks in profiler

base/profiler/tracked_time.cc

Index: base/profiler/tracked_time.cc
===================================================================
--- base/profiler/tracked_time.cc	(revision 0)
+++ base/profiler/tracked_time.cc	(revision 0)
@@ -0,0 +1,80 @@
+// Copyright (c) 2011 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 "base/profiler/tracked_time.h"
+
+#include "build/build_config.h"
+
+#if defined(OS_WIN)
+#include <mmsystem.h>  // Declare timeGetTime()... after including build_config.
+#endif
+
+namespace tracked_objects {
+
+#if defined(USE_FAST_TIME_CLASS_FOR_DURATION_CALCULATIONS)
+
+Duration::Duration() : ms_(0) {}
+Duration::Duration(int32 duration) : ms_(duration) {}
+
+Duration& Duration::operator+=(const Duration& other) {
+  ms_ += other.ms_;
+  return *this;
+}
+
+Duration Duration::operator+(const Duration& other) const {
+  return Duration(ms_ + other.ms_);
+}
+
+bool Duration::operator==(const Duration& other) const {
+  return ms_ == other.ms_;
+}
+
+bool Duration::operator!=(const Duration& other) const {
+  return ms_ != other.ms_;
+}
+
+bool Duration::operator>(const Duration& other) const {
+  return ms_ > other.ms_;
+}
+
+// static
+Duration Duration::FromMilliseconds(int ms) { return Duration(ms); }
+
+int32 Duration::InMilliseconds() const { return ms_; }
+
+//------------------------------------------------------------------------------
+
+TrackedTime::TrackedTime() : ms_(0) {}
+TrackedTime::TrackedTime(int32 ms) : ms_(ms) {}
+TrackedTime::TrackedTime(const base::TimeTicks& time)
+    : ms_((time - base::TimeTicks()).InMilliseconds()) {
+}
+
+// static
+TrackedTime TrackedTime::Now() {
+#if defined(OS_WIN)
+  // Use lock-free accessor to 32 bit time.
+  // Note that TimeTicks::Now() is built on this, so we have "compatible"
+  // times when we down-convert a TimeTicks sample.
+  // TODO(jar): Surface this interface via something in base/time.h.
+  return TrackedTime(static_cast<int32>(timeGetTime()));
+#else
+  // Posix has nice cheap 64 bit times, so we just down-convert it.
+  return TrackedTime(base::TimeTicks::Now());
+#endif  // OS_WIN
+}
+
+Duration TrackedTime::operator-(const TrackedTime& other) const {
+  return Duration(ms_ - other.ms_);
+}
+
+TrackedTime TrackedTime::operator+(const Duration& other) const {
+  return TrackedTime(ms_ + other.ms_);
+}
+
+bool TrackedTime::is_null() const { return ms_ == 0; }
+
+#endif  // USE_FAST_TIME_CLASS_FOR_DURATION_CALCULATIONS
+
+}  // namespace tracked_objects