Android15跟踪函数调用关系

注：这里介绍Android15 Camera系统调试用到的跟踪函数调用关系的一些方法。

使用CallStack类dump调用栈

例如，跟踪Camera3OutputStream对象的创建。

1.dump调用栈

步骤1.Camera3OutputStream.h/.cpp中通过CallStack类打印调用信息.

复制代码

//frameworks/av/services/camera/libcameraservice/device3/Camera3OutputStream.h
//添加dumpCallStack()接口，封装CallStack调用
class Camera3OutputStream :
        public Camera3IOStreamBase,
        public Camera3OutputStreamInterface {
    ...
    static void dumpCallStack(const char* prefix);
};
//frameworks/av/services/camera/libcameraservice/device3/Camera3OutputStream.cpp
//添加dumpCallStack()接口实现
#include "utils/CallStack.h"
void Camera3OutputStream::dumpCallStack(const char* prefix)
{
    android::CallStack stack(prefix);
    stack.update();
    //stack.log("CAMERA_CALLSTACK");
}

步骤2.Camera3OutputStream需要的位置添加dumpCallStack()调用

复制代码

//frameworks/av/services/camera/libcameraservice/device3/Camera3OutputStream.cpp
Camera3OutputStream::Camera3OutputStream(int id,
        sp<Surface> consumer,
        uint32_t width, uint32_t height, int format,
        android_dataspace dataSpace, camera_stream_rotation_t rotation,
        nsecs_t timestampOffset, const std::string& physicalCameraId,
        const std::unordered_set<int32_t> &sensorPixelModeUsed, IPCTransport transport,
        int setId, bool isMultiResolution, int64_t dynamicRangeProfile,
        int64_t streamUseCase, bool deviceTimeBaseIsRealtime, int timestampBase,
        int mirrorMode, int32_t colorSpace, bool useReadoutTimestamp) :
        Camera3IOStreamBase(id, CAMERA_STREAM_OUTPUT, width, height,
                        /*maxSize*/0, format, dataSpace, rotation,
                        physicalCameraId, sensorPixelModesUsec, setId, isMultiResolution,
                        dynamicRangeProfile, streamUseCase, deviceTimeBaseRealtime,
                        timestampBase, colorSpace),
        mConsumer(consumer),
        mTransform(0),
        ... {
        
        dumpCallStack("Camera3OutputStream::Camera3OutputStream1");
        ...
}

步骤3.编译并更新cameraserver到设备

步骤4.重启系统

步骤5.操作相机

2.查看调用栈

通过logcat抓取日志，有如下调用关系