core/jni/android_view_FrameMetricsObserver.h

/*
 * Copyright (C) 2019 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.
 */

#include "jni.h"
#include "core_jni_helpers.h"

#include "android_os_MessageQueue.h"

#include <FrameInfo.h>
#include <FrameMetricsObserver.h>

namespace android {

/*
 * Implements JNI layer for hwui frame metrics reporting.
 */
class FrameMetricsObserverProxy : public uirenderer::FrameMetricsObserver {
public:
    FrameMetricsObserverProxy(JavaVM *vm, jobject observer);

    ~FrameMetricsObserverProxy();

    jweak getObserverReference() {
        return mObserverWeak;
    }

    bool getNextBuffer(JNIEnv* env, jlongArray sink, int* dropCount);

    virtual void notify(const int64_t* stats);

private:
    static const int kBufferSize = static_cast<int>(uirenderer::FrameInfoIndex::NumIndexes);
    static constexpr int kRingSize = 3;

    class FrameMetricsNotification {
    public:
        FrameMetricsNotification() : hasData(false) {}

        std::atomic_bool hasData;
        int64_t buffer[kBufferSize];
        int dropCount = 0;
    };

    JavaVM* const mVm;
    jweak mObserverWeak;

    sp<MessageQueue> mMessageQueue;
    sp<MessageHandler> mMessageHandler;
    Message mMessage;

    int mNextFree = 0;
    int mNextInQueue = 0;
    FrameMetricsNotification mRingBuffer[kRingSize];

    int mDroppedReports = 0;
};

} // namespace android