third_party/blink/renderer/core/workers/experimental/thread_pool_thread.h

// Copyright 2018 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.

#ifndef THIRD_PARTY_BLINK_RENDERER_CORE_WORKERS_EXPERIMENTAL_THREAD_POOL_THREAD_H_
#define THIRD_PARTY_BLINK_RENDERER_CORE_WORKERS_EXPERIMENTAL_THREAD_POOL_THREAD_H_

#include "third_party/blink/renderer/core/workers/worker_backing_thread.h"
#include "third_party/blink/renderer/core/workers/worker_thread.h"

namespace blink {
class ExecutionContext;
class ThreadedObjectProxyBase;

class ThreadPoolThread final : public WorkerThread {
 public:
  enum ThreadBackingPolicy { kWorker, kWorklet };

  ThreadPoolThread(ExecutionContext*,
                   ThreadedObjectProxyBase&,
                   ThreadBackingPolicy);
  ~ThreadPoolThread() override = default;

  void IncrementTasksInProgressCount() {
    DCHECK(IsMainThread());
    tasks_in_progress_++;
  }
  void DecrementTasksInProgressCount() {
    DCHECK(IsMainThread());
    DCHECK_GT(tasks_in_progress_, 0u);
    tasks_in_progress_--;
  }
  size_t GetTasksInProgressCount() const {
    DCHECK(IsMainThread());
    return tasks_in_progress_;
  }

  bool IsWorklet() const { return backing_policy_ == kWorklet; }

 private:
  WorkerBackingThread& GetWorkerBackingThread() override {
    return *worker_backing_thread_;
  }
  void ClearWorkerBackingThread() override { worker_backing_thread_ = nullptr; }

  WorkerOrWorkletGlobalScope* CreateWorkerGlobalScope(
      std::unique_ptr<GlobalScopeCreationParams> creation_params) override;

  WebThreadType GetThreadType() const override {
    // TODO(japhet): Replace with WebThreadType::kThreadPoolWorkerThread.
    return WebThreadType::kDedicatedWorkerThread;
  }
  std::unique_ptr<WorkerBackingThread> worker_backing_thread_;
  size_t tasks_in_progress_ = 0;
  const ThreadBackingPolicy backing_policy_;
};

class ThreadPoolThreadProvider {
 public:
  virtual ThreadPoolThread* GetLeastBusyThread() = 0;
};

}  // namespace blink

#endif  // THIRD_PARTY_BLINK_RENDERER_CORE_WORKERS_EXPERIMENTAL_THREAD_POOL_THREAD_H_