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content / browser / scheduler / responsiveness / metric_source.h [blame]
// Copyright 2019 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#ifndef CONTENT_BROWSER_SCHEDULER_RESPONSIVENESS_METRIC_SOURCE_H_
#define CONTENT_BROWSER_SCHEDULER_RESPONSIVENESS_METRIC_SOURCE_H_
#include <memory>
#include "base/functional/callback.h"
#include "base/functional/callback_helpers.h"
#include "base/gtest_prod_util.h"
#include "base/memory/raw_ptr.h"
#include "content/common/content_export.h"
namespace base {
struct PendingTask;
} // namespace base
namespace content {
namespace responsiveness {
class MessageLoopObserver;
class NativeEventObserver;
// This class represents the source of browser responsiveness metrics.
// This class watches events and tasks processed on the UI and IO threads of the
// browser process. It notifies the registered Delegate implementer about
// event and task execution through the WillRun* and DidRun* methods.
//
// This class must only be constructed/destroyed on the UI thread. It has some
// private members that are affine to the IO thread. It takes care of deleting
// them appropriately.
//
// TODO(erikchen): Once the browser scheduler is implemented, this entire class
// should become simpler, as either BrowserUIThreadScheduler or
// BrowserIOThreadScheduler should implement much of the same functionality.
class CONTENT_EXPORT MetricSource {
public:
class CONTENT_EXPORT Delegate {
public:
virtual ~Delegate();
// Interface for SetUp/TearDown on UI/IO threads in the implementer.
virtual void SetUpOnIOThread() = 0;
virtual void TearDownOnUIThread() = 0;
virtual void TearDownOnIOThread() = 0;
// These methods are called by the MessageLoopObserver of the UI thread to
// allow Delegate to collect metadata about the tasks being run.
virtual void WillRunTaskOnUIThread(const base::PendingTask* task,
bool was_blocked_or_low_priority) = 0;
virtual void DidRunTaskOnUIThread(const base::PendingTask* task) = 0;
// These methods are called by the MessageLoopObserver of the IO thread to
// allow Delegate to collect metadata about the tasks being run.
virtual void WillRunTaskOnIOThread(const base::PendingTask* task,
bool was_blocked_or_low_priority) = 0;
virtual void DidRunTaskOnIOThread(const base::PendingTask* task) = 0;
// These methods are called by the NativeEventObserver of the UI thread to
// allow Delegate to collect metadata about the events being run.
virtual void WillRunEventOnUIThread(const void* opaque_identifier) = 0;
virtual void DidRunEventOnUIThread(const void* opaque_identifier) = 0;
};
explicit MetricSource(Delegate* delegate);
MetricSource(const MetricSource&) = delete;
MetricSource& operator=(const MetricSource&) = delete;
virtual ~MetricSource();
// Must be called immediately after the constructor. This cannot be called
// from the constructor because subclasses [for tests] need to be able to
// override functions.
void SetUp();
// Destruction requires a thread-hop to the IO thread so cannot be completed
// synchronously. Owners of this class calling Destroy() should pass one
// base::ScopedClosureRunner for final cleanup when this class finishes the
// destruction on the UI thread. It's safe to delete this instance in
// |on_finish_destroy|.
void Destroy(base::ScopedClosureRunner on_finish_destroy);
protected:
virtual std::unique_ptr<NativeEventObserver> CreateNativeEventObserver();
virtual void RegisterMessageLoopObserverUI();
virtual void RegisterMessageLoopObserverIO();
private:
void SetUpOnIOThread();
void TearDownOnIOThread(base::ScopedClosureRunner on_finish_destroy);
void TearDownOnUIThread(base::ScopedClosureRunner on_finish_destroy);
raw_ptr<Delegate> delegate_;
// The following members are all affine to the UI thread.
std::unique_ptr<MessageLoopObserver> message_loop_observer_ui_;
std::unique_ptr<NativeEventObserver> native_event_observer_ui_;
// The following members are all affine to the IO thread.
std::unique_ptr<MessageLoopObserver> message_loop_observer_io_;
bool destroy_was_called_ = false;
};
} // namespace responsiveness
} // namespace content
#endif // CONTENT_BROWSER_SCHEDULER_RESPONSIVENESS_METRIC_SOURCE_H_