M之前版本在一个进程中创建media相关所有服务

av/media/mediaserver/main_mediaserver.cpp

sp<IServiceManager>sm=defaultServiceManager();ALOGI("ServiceManager:%p",sm.get());AudioFlinger::instantiate();MediaPlayerService::instantiate();ResourceManagerService::instantiate();CameraService::instantiate();AudioPolicyService::instantiate();SoundTriggerHwService::instantiate();RadioService::instantiate();registerExtensions();ProcessState::self()->startThreadPool();IPCThreadState::self()->joinThreadPool();

N版本将各个服务转移到不同进程中进行创建

media/audioserver/main_audioserver.cpp:AudioPolicyService::instantiate();camera/cameraserver/main_cameraserver.cpp:CameraService::instantiate();media/mediaserver/main_mediaserver.cpp:MediaPlayerService::instantiate();