services/surfaceflinger/Scheduler/EventThread.h - third_party/android/platform/frameworks/native - Git at Google

 /*
  * Copyright (C) 2011 The Android Open Source Project
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
  *      http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */

 #pragma once

 #include <android-base/thread_annotations.h>
 #include <gui/DisplayEventReceiver.h>
 #include <gui/IDisplayEventConnection.h>
 #include <private/gui/BitTube.h>
 #include <sys/types.h>
 #include <utils/Errors.h>

 #include <condition_variable>
 #include <cstdint>
 #include <deque>
 #include <mutex>
 #include <optional>
 #include <thread>
 #include <vector>

 #include "DisplayHardware/DisplayMode.h"

 // ---------------------------------------------------------------------------
 namespace android {
 // ---------------------------------------------------------------------------

 class EventThread;
 class EventThreadTest;
 class SurfaceFlinger;

 namespace frametimeline {
 class TokenManager;
 } // namespace frametimeline

 // ---------------------------------------------------------------------------

 using ResyncCallback = std::function<void()>;
 using FrameRateOverride = DisplayEventReceiver::Event::FrameRateOverride;

 enum class VSyncRequest {
     None = -2,
     // Single wakes up for the next two frames to avoid scheduler overhead
     Single = -1,
     // SingleSuppressCallback only wakes up for the next frame
     SingleSuppressCallback = 0,
     Periodic = 1,
     // Subsequent values are periods.
 };

 class VSyncSource {
 public:
     class Callback {
     public:
         virtual ~Callback() {}
         virtual void onVSyncEvent(nsecs_t when, nsecs_t expectedVSyncTimestamp,
                                   nsecs_t deadlineTimestamp) = 0;
     };

     virtual ~VSyncSource() {}

     virtual const char* getName() const = 0;
     virtual void setVSyncEnabled(bool enable) = 0;
     virtual void setCallback(Callback* callback) = 0;
     virtual void setDuration(std::chrono::nanoseconds workDuration,
                              std::chrono::nanoseconds readyDuration) = 0;

     virtual void dump(std::string& result) const = 0;
 };

 class EventThreadConnection : public BnDisplayEventConnection {
 public:
     EventThreadConnection(EventThread*, uid_t callingUid, ResyncCallback,
                           ISurfaceComposer::EventRegistrationFlags eventRegistration = {});
     virtual ~EventThreadConnection();

     virtual status_t postEvent(const DisplayEventReceiver::Event& event);

     status_t stealReceiveChannel(gui::BitTube* outChannel) override;
     status_t setVsyncRate(uint32_t rate) override;
     void requestNextVsync() override; // asynchronous

     // Called in response to requestNextVsync.
     const ResyncCallback resyncCallback;

     VSyncRequest vsyncRequest = VSyncRequest::None;
     const uid_t mOwnerUid;
     const ISurfaceComposer::EventRegistrationFlags mEventRegistration;

 private:
     virtual void onFirstRef();
     EventThread* const mEventThread;
     gui::BitTube mChannel;

     std::vector<DisplayEventReceiver::Event> mPendingEvents;
 };

 class EventThread {
 public:
     virtual ~EventThread();

     virtual sp<EventThreadConnection> createEventConnection(
             ResyncCallback,
             ISurfaceComposer::EventRegistrationFlags eventRegistration = {}) const = 0;

     // called before the screen is turned off from main thread
     virtual void onScreenReleased() = 0;

     // called after the screen is turned on from main thread
     virtual void onScreenAcquired() = 0;

     virtual void onHotplugReceived(PhysicalDisplayId displayId, bool connected) = 0;

     // called when SF changes the active mode and apps needs to be notified about the change
     virtual void onModeChanged(PhysicalDisplayId displayId, DisplayModeId modeId,
                                nsecs_t vsyncPeriod) = 0;

     // called when SF updates the Frame Rate Override list
     virtual void onFrameRateOverridesChanged(PhysicalDisplayId displayId,
                                              std::vector<FrameRateOverride> overrides) = 0;

     virtual void dump(std::string& result) const = 0;

     virtual void setDuration(std::chrono::nanoseconds workDuration,
                              std::chrono::nanoseconds readyDuration) = 0;

     virtual status_t registerDisplayEventConnection(
             const sp<EventThreadConnection>& connection) = 0;
     virtual void setVsyncRate(uint32_t rate, const sp<EventThreadConnection>& connection) = 0;
     // Requests the next vsync. If resetIdleTimer is set to true, it resets the idle timer.
     virtual void requestNextVsync(const sp<EventThreadConnection>& connection) = 0;

     // Retrieves the number of event connections tracked by this EventThread.
     virtual size_t getEventThreadConnectionCount() = 0;
 };

 namespace impl {

 class EventThread : public android::EventThread, private VSyncSource::Callback {
 public:
     using InterceptVSyncsCallback = std::function<void(nsecs_t)>;
     using ThrottleVsyncCallback = std::function<bool(nsecs_t, uid_t)>;
     using GetVsyncPeriodFunction = std::function<nsecs_t(uid_t)>;

     EventThread(std::unique_ptr<VSyncSource>, frametimeline::TokenManager*, InterceptVSyncsCallback,
                 ThrottleVsyncCallback, GetVsyncPeriodFunction);
     ~EventThread();

     sp<EventThreadConnection> createEventConnection(
             ResyncCallback,
             ISurfaceComposer::EventRegistrationFlags eventRegistration = {}) const override;

     status_t registerDisplayEventConnection(const sp<EventThreadConnection>& connection) override;
     void setVsyncRate(uint32_t rate, const sp<EventThreadConnection>& connection) override;
     void requestNextVsync(const sp<EventThreadConnection>& connection) override;

     // called before the screen is turned off from main thread
     void onScreenReleased() override;

     // called after the screen is turned on from main thread
     void onScreenAcquired() override;

     void onHotplugReceived(PhysicalDisplayId displayId, bool connected) override;

     void onModeChanged(PhysicalDisplayId displayId, DisplayModeId modeId,
                        nsecs_t vsyncPeriod) override;

     void onFrameRateOverridesChanged(PhysicalDisplayId displayId,
                                      std::vector<FrameRateOverride> overrides) override;

     void dump(std::string& result) const override;

     void setDuration(std::chrono::nanoseconds workDuration,
                      std::chrono::nanoseconds readyDuration) override;

     size_t getEventThreadConnectionCount() override;

 private:
     friend EventThreadTest;

     using DisplayEventConsumers = std::vector<sp<EventThreadConnection>>;

     void threadMain(std::unique_lock<std::mutex>& lock) REQUIRES(mMutex);

     bool shouldConsumeEvent(const DisplayEventReceiver::Event& event,
                             const sp<EventThreadConnection>& connection) const REQUIRES(mMutex);
     void dispatchEvent(const DisplayEventReceiver::Event& event,
                        const DisplayEventConsumers& consumers) REQUIRES(mMutex);

     void removeDisplayEventConnectionLocked(const wp<EventThreadConnection>& connection)
             REQUIRES(mMutex);

     // Implements VSyncSource::Callback
     void onVSyncEvent(nsecs_t timestamp, nsecs_t expectedVSyncTimestamp,
                       nsecs_t deadlineTimestamp) override;

     const std::unique_ptr<VSyncSource> mVSyncSource GUARDED_BY(mMutex);
     frametimeline::TokenManager* const mTokenManager;

     const InterceptVSyncsCallback mInterceptVSyncsCallback;
     const ThrottleVsyncCallback mThrottleVsyncCallback;
     const GetVsyncPeriodFunction mGetVsyncPeriodFunction;
     const char* const mThreadName;

     std::thread mThread;
     mutable std::mutex mMutex;
     mutable std::condition_variable mCondition;

     std::vector<wp<EventThreadConnection>> mDisplayEventConnections GUARDED_BY(mMutex);
     std::deque<DisplayEventReceiver::Event> mPendingEvents GUARDED_BY(mMutex);

     // VSYNC state of connected display.
     struct VSyncState {
         explicit VSyncState(PhysicalDisplayId displayId) : displayId(displayId) {}

         const PhysicalDisplayId displayId;

         // Number of VSYNC events since display was connected.
         uint32_t count = 0;

         // True if VSYNC should be faked, e.g. when display is off.
         bool synthetic = false;
     };

     // TODO(b/74619554): Create per-display threads waiting on respective VSYNC signals,
     // and support headless mode by injecting a fake display with synthetic VSYNC.
     std::optional<VSyncState> mVSyncState GUARDED_BY(mMutex);

     // State machine for event loop.
     enum class State {
         Idle,
         Quit,
         SyntheticVSync,
         VSync,
     };

     State mState GUARDED_BY(mMutex) = State::Idle;

     static const char* toCString(State);
 };

 // ---------------------------------------------------------------------------

 } // namespace impl
 } // namespace android
	/*
	* Copyright (C) 2011 The Android Open Source Project
	*
	* Licensed under the Apache License, Version 2.0 (the "License");
	* you may not use this file except in compliance with the License.
	* You may obtain a copy of the License at
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing, software
	* distributed under the License is distributed on an "AS IS" BASIS,
	* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	* See the License for the specific language governing permissions and
	* limitations under the License.
	*/

	#pragma once

	#include <android-base/thread_annotations.h>
	#include <gui/DisplayEventReceiver.h>
	#include <gui/IDisplayEventConnection.h>
	#include <private/gui/BitTube.h>
	#include <sys/types.h>
	#include <utils/Errors.h>

	#include <condition_variable>
	#include <cstdint>
	#include <deque>
	#include <mutex>
	#include <optional>
	#include <thread>
	#include <vector>

	#include "DisplayHardware/DisplayMode.h"

	// ---------------------------------------------------------------------------
	namespace android {
	// ---------------------------------------------------------------------------

	class EventThread;
	class EventThreadTest;
	class SurfaceFlinger;

	namespace frametimeline {
	class TokenManager;
	} // namespace frametimeline

	// ---------------------------------------------------------------------------

	using ResyncCallback = std::function<void()>;
	using FrameRateOverride = DisplayEventReceiver::Event::FrameRateOverride;

	enum class VSyncRequest {
	None = -2,
	// Single wakes up for the next two frames to avoid scheduler overhead
	Single = -1,
	// SingleSuppressCallback only wakes up for the next frame
	SingleSuppressCallback = 0,
	Periodic = 1,
	// Subsequent values are periods.
	};

	class VSyncSource {
	public:
	class Callback {
	public:
	virtual ~Callback() {}
	virtual void onVSyncEvent(nsecs_t when, nsecs_t expectedVSyncTimestamp,
	nsecs_t deadlineTimestamp) = 0;
	};

	virtual ~VSyncSource() {}

	virtual const char* getName() const = 0;
	virtual void setVSyncEnabled(bool enable) = 0;
	virtual void setCallback(Callback* callback) = 0;
	virtual void setDuration(std::chrono::nanoseconds workDuration,
	std::chrono::nanoseconds readyDuration) = 0;

	virtual void dump(std::string& result) const = 0;
	};

	class EventThreadConnection : public BnDisplayEventConnection {
	public:
	EventThreadConnection(EventThread*, uid_t callingUid, ResyncCallback,
	ISurfaceComposer::EventRegistrationFlags eventRegistration = {});
	virtual ~EventThreadConnection();

	virtual status_t postEvent(const DisplayEventReceiver::Event& event);

	status_t stealReceiveChannel(gui::BitTube* outChannel) override;
	status_t setVsyncRate(uint32_t rate) override;
	void requestNextVsync() override; // asynchronous

	// Called in response to requestNextVsync.
	const ResyncCallback resyncCallback;

	VSyncRequest vsyncRequest = VSyncRequest::None;
	const uid_t mOwnerUid;
	const ISurfaceComposer::EventRegistrationFlags mEventRegistration;

	private:
	virtual void onFirstRef();
	EventThread* const mEventThread;
	gui::BitTube mChannel;

	std::vector<DisplayEventReceiver::Event> mPendingEvents;
	};

	class EventThread {
	public:
	virtual ~EventThread();

	virtual sp<EventThreadConnection> createEventConnection(
	ResyncCallback,
	ISurfaceComposer::EventRegistrationFlags eventRegistration = {}) const = 0;

	// called before the screen is turned off from main thread
	virtual void onScreenReleased() = 0;

	// called after the screen is turned on from main thread
	virtual void onScreenAcquired() = 0;

	virtual void onHotplugReceived(PhysicalDisplayId displayId, bool connected) = 0;

	// called when SF changes the active mode and apps needs to be notified about the change
	virtual void onModeChanged(PhysicalDisplayId displayId, DisplayModeId modeId,
	nsecs_t vsyncPeriod) = 0;

	// called when SF updates the Frame Rate Override list
	virtual void onFrameRateOverridesChanged(PhysicalDisplayId displayId,
	std::vector<FrameRateOverride> overrides) = 0;

	virtual void dump(std::string& result) const = 0;

	virtual void setDuration(std::chrono::nanoseconds workDuration,
	std::chrono::nanoseconds readyDuration) = 0;

	virtual status_t registerDisplayEventConnection(
	const sp<EventThreadConnection>& connection) = 0;
	virtual void setVsyncRate(uint32_t rate, const sp<EventThreadConnection>& connection) = 0;
	// Requests the next vsync. If resetIdleTimer is set to true, it resets the idle timer.
	virtual void requestNextVsync(const sp<EventThreadConnection>& connection) = 0;

	// Retrieves the number of event connections tracked by this EventThread.
	virtual size_t getEventThreadConnectionCount() = 0;
	};

	namespace impl {

	class EventThread : public android::EventThread, private VSyncSource::Callback {
	public:
	using InterceptVSyncsCallback = std::function<void(nsecs_t)>;
	using ThrottleVsyncCallback = std::function<bool(nsecs_t, uid_t)>;
	using GetVsyncPeriodFunction = std::function<nsecs_t(uid_t)>;

	EventThread(std::unique_ptr<VSyncSource>, frametimeline::TokenManager*, InterceptVSyncsCallback,
	ThrottleVsyncCallback, GetVsyncPeriodFunction);
	~EventThread();

	sp<EventThreadConnection> createEventConnection(
	ResyncCallback,
	ISurfaceComposer::EventRegistrationFlags eventRegistration = {}) const override;

	status_t registerDisplayEventConnection(const sp<EventThreadConnection>& connection) override;
	void setVsyncRate(uint32_t rate, const sp<EventThreadConnection>& connection) override;
	void requestNextVsync(const sp<EventThreadConnection>& connection) override;

	// called before the screen is turned off from main thread
	void onScreenReleased() override;

	// called after the screen is turned on from main thread
	void onScreenAcquired() override;

	void onHotplugReceived(PhysicalDisplayId displayId, bool connected) override;

	void onModeChanged(PhysicalDisplayId displayId, DisplayModeId modeId,
	nsecs_t vsyncPeriod) override;

	void onFrameRateOverridesChanged(PhysicalDisplayId displayId,
	std::vector<FrameRateOverride> overrides) override;

	void dump(std::string& result) const override;

	void setDuration(std::chrono::nanoseconds workDuration,
	std::chrono::nanoseconds readyDuration) override;

	size_t getEventThreadConnectionCount() override;

	private:
	friend EventThreadTest;

	using DisplayEventConsumers = std::vector<sp<EventThreadConnection>>;

	void threadMain(std::unique_lock<std::mutex>& lock) REQUIRES(mMutex);

	bool shouldConsumeEvent(const DisplayEventReceiver::Event& event,
	const sp<EventThreadConnection>& connection) const REQUIRES(mMutex);
	void dispatchEvent(const DisplayEventReceiver::Event& event,
	const DisplayEventConsumers& consumers) REQUIRES(mMutex);

	void removeDisplayEventConnectionLocked(const wp<EventThreadConnection>& connection)
	REQUIRES(mMutex);

	// Implements VSyncSource::Callback
	void onVSyncEvent(nsecs_t timestamp, nsecs_t expectedVSyncTimestamp,
	nsecs_t deadlineTimestamp) override;

	const std::unique_ptr<VSyncSource> mVSyncSource GUARDED_BY(mMutex);
	frametimeline::TokenManager* const mTokenManager;

	const InterceptVSyncsCallback mInterceptVSyncsCallback;
	const ThrottleVsyncCallback mThrottleVsyncCallback;
	const GetVsyncPeriodFunction mGetVsyncPeriodFunction;
	const char* const mThreadName;

	std::thread mThread;
	mutable std::mutex mMutex;
	mutable std::condition_variable mCondition;

	std::vector<wp<EventThreadConnection>> mDisplayEventConnections GUARDED_BY(mMutex);
	std::deque<DisplayEventReceiver::Event> mPendingEvents GUARDED_BY(mMutex);

	// VSYNC state of connected display.
	struct VSyncState {
	explicit VSyncState(PhysicalDisplayId displayId) : displayId(displayId) {}

	const PhysicalDisplayId displayId;

	// Number of VSYNC events since display was connected.
	uint32_t count = 0;

	// True if VSYNC should be faked, e.g. when display is off.
	bool synthetic = false;
	};

	// TODO(b/74619554): Create per-display threads waiting on respective VSYNC signals,
	// and support headless mode by injecting a fake display with synthetic VSYNC.
	std::optional<VSyncState> mVSyncState GUARDED_BY(mMutex);

	// State machine for event loop.
	enum class State {
	Idle,
	Quit,
	SyntheticVSync,
	VSync,
	};

	State mState GUARDED_BY(mMutex) = State::Idle;

	static const char* toCString(State);
	};

	// ---------------------------------------------------------------------------

	} // namespace impl
	} // namespace android