| // Copyright 2017 The Chromium Authors |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| #include "third_party/blink/renderer/core/loader/long_task_detector.h" |
| |
| #include "base/time/time.h" |
| #include "third_party/blink/public/platform/platform.h" |
| #include "third_party/blink/renderer/platform/scheduler/public/thread.h" |
| #include "third_party/blink/renderer/platform/wtf/wtf.h" |
| |
| namespace blink { |
| |
| constexpr base::TimeDelta LongTaskDetector::kLongTaskThreshold; |
| |
| // static |
| LongTaskDetector& LongTaskDetector::Instance() { |
| DEFINE_STATIC_LOCAL(Persistent<LongTaskDetector>, long_task_detector, |
| (MakeGarbageCollected<LongTaskDetector>())); |
| DCHECK(IsMainThread()); |
| return *long_task_detector; |
| } |
| |
| LongTaskDetector::LongTaskDetector() = default; |
| |
| void LongTaskDetector::RegisterObserver(LongTaskObserver* observer) { |
| DCHECK(IsMainThread()); |
| DCHECK(observer); |
| DCHECK(!iterating_); |
| if (observers_.insert(observer).is_new_entry && observers_.size() == 1) { |
| // Number of observers just became non-zero. |
| Thread::Current()->AddTaskTimeObserver(this); |
| } |
| } |
| |
| void LongTaskDetector::UnregisterObserver(LongTaskObserver* observer) { |
| DCHECK(IsMainThread()); |
| if (iterating_) { |
| observers_to_be_removed_.push_back(observer); |
| return; |
| } |
| observers_.erase(observer); |
| if (observers_.size() == 0) { |
| Thread::Current()->RemoveTaskTimeObserver(this); |
| } |
| } |
| |
| void LongTaskDetector::DidProcessTask(base::TimeTicks start_time, |
| base::TimeTicks end_time) { |
| if ((end_time - start_time) < LongTaskDetector::kLongTaskThreshold) |
| return; |
| |
| iterating_ = true; |
| for (auto& observer : observers_) { |
| observer->OnLongTaskDetected(start_time, end_time); |
| } |
| iterating_ = false; |
| |
| for (const auto& observer : observers_to_be_removed_) { |
| UnregisterObserver(observer); |
| } |
| observers_to_be_removed_.clear(); |
| } |
| |
| void LongTaskDetector::Trace(Visitor* visitor) const { |
| visitor->Trace(observers_); |
| visitor->Trace(observers_to_be_removed_); |
| } |
| |
| } // namespace blink |