一、setDataProfile(apn.modemCognitive->??aosp apn not invoke setDataProfilesAsNeeded??)：
DcTracker.setDataProfilesAsNeeded
    ->for (ApnSetting apn : mAllApnSettings) {
    ->if (apn.modemCognitive) {
    ->...->RIL.setDataProfile->RIL_REQUEST_SET_DATA_PROFILE->...->ril_service.cpp
->RadioImpl::setDataProfile->RIL_REQUEST_SET_DATA_PROFILE->...->reference-ril.c.onRequest->??

Telephony.Carriers.MODEM_COGNITIVE:
        /**
         * Is the apn setting to be set in modem
         * <P>Type: INTEGER (boolean)</P>
         *@hide
         */
        public static final String MODEM_COGNITIVE = "modem_cognitive";

(setModemCognitive:
DevicePolicyManager.getOverrideApns->DevicePolicyManagerService.getOverrideApns
->getOverrideApnsUnchecked->ApnSetting.makeApnSetting->setModemCognitive)


二、requestNetwork set mApnSetting(from APN_TYPE_DUN/mAllApnSettings):
DcTracker.requestNetwork->...->trySetupData
    ->int radioTech = mPhone.getServiceState().getRilDataRadioTechnology();
    ->ArrayList<ApnSetting> waitingApns =
                        buildWaitingApns(apnContext.getApnType(), radioTech);
->...(APN_TYPE_DUN/mPreferredApn/mAllApnSettings(
        ->for (ApnSetting apn : mAllApnSettings) {
        ->if (apn.canHandleType(requestedApnType)) {
        ->ServiceState.bitmaskHasTech(apn.networkTypeBitmask,
                            ServiceState.rilRadioTechnologyToNetworkType(radioTech))))
    ->apnContext.setWaitingApns(waitingApns);->RetryManager.setWaitingApns->mWaitingApns
    ->setupData
        ->apnSetting = apnContext.getNextApnSetting();->RetryManager.getNextApnSetting->mWaitingApns.get
        ->apnContext.setApnSetting(apnSetting);->apnContext.mApnSetting

mPreferredApn(from apnContext.getApnSetting):
DcTracker.requestNetwork->...->setupData->EVENT_DATA_SETUP_COMPLETE->...->onDataSetupComplete
    ->ApnSetting apn = apnContext.getApnSetting();->ApnContext.mApnSetting
    ->mPreferredApn = apn;
    ->setPreferredApn(mPreferredApn.id)

buildWaitingApns:
    /**
     * Build a list of APNs to be used to create PDP‘s.
    private ArrayList<ApnSetting> buildWaitingApns(String requestedApnType, int radioTech) {

setupDataCall mApnSetting(from apnContext.getApnSetting):
DataConnection.DcInactiveState.processMessage->EVENT_CONNECT
    ->initConnection->mApnSetting = apnContext.getApnSetting();->ApnContext.mApnSetting
    ->onConnect(ConnectionParams cp)
        ->DataProfile dp = DcTracker.createDataProfile(mApnSetting, cp.mProfileId);
        ->DataServiceManager.setupDataCall(dp)->...->RIL.setupDataCall(DataProfile dataProfile)
            ->// Convert to HAL data profile
                    DataProfileInfo dpi = convertToHalDataProfile(dataProfile);
            ->radioProxy.setupDataCall(rr.mSerial, dataRat, dpi,
                                    dataProfile.isModemCognitive())
                                    

mRilDataRadioTechnology(getRilDataRadioTechnology):
ServiceStateTracker.EVENT_POLL_STATE_GPRS
    ->NetworkRegistrationState networkRegState = (NetworkRegistrationState) ar.result;
    ->int newDataRat = ServiceState.networkTypeToRilRadioTechnology(
                        networkRegState.getAccessNetworkTechnology());->mAccessNetworkTechnology
    ->ServiceState.setRilDataRadioTechnology(newDataRat)->this.mRilDataRadioTechnology = newDataRat;<-getRilDataRadioTechnology

NetworkRegistrationState.mAccessNetworkTechnology(from mCi):
CellularNetworkService.getNetworkRegistrationState->mPhone.mCi.getDataRegistrationState->GET_PS_REGISTRATION_STATE_DONE
->...->getRegistrationStateFromResult->createRegistrationStateFromDataRegState(Object result)
    ->if (result instanceof android.hardware.radio.V1_0.DataRegStateResult) {
    ->android.hardware.radio.V1_0.DataRegStateResult dataRegState =
                        (android.hardware.radio.V1_0.DataRegStateResult) result;
    ->int accessNetworkTechnology = getAccessNetworkTechnologyFromRat(dataRegState.rat);->ServiceState.rilRadioTechnologyToNetworkType(rilRat)
    ->return new NetworkRegistrationState(transportType, domain, regState,
                        accessNetworkTechnology, reasonForDenial, emergencyOnly, availableServices,
                        cellIdentity, maxDataCalls);->mAccessNetworkTechnology = accessNetworkTechnology;
    ->...(V1_2)

(ServiceStateTracker.pollState
    ->mRegStateManagers.get(AccessNetworkConstants.TransportType.WWAN)
                        .getNetworkRegistrationState(NetworkRegistrationState.DOMAIN_PS,
                        obtainMessage(EVENT_POLL_STATE_GPRS, mPollingContext));
private final SparseArray<NetworkRegistrationManager> mRegStateManagers = new SparseArray<>();
NetworkRegistrationManager)

ServiceState
    public static int rilRadioTechnologyToNetworkType(@RilRadioTechnology int rt) {
        switch(rt) {
        case ServiceState.RIL_RADIO_TECHNOLOGY_GPRS:
            return TelephonyManager.NETWORK_TYPE_GPRS;
        case ServiceState.RIL_RADIO_TECHNOLOGY_EDGE:
            return TelephonyManager.NETWORK_TYPE_EDGE;
        case ServiceState.RIL_RADIO_TECHNOLOGY_UMTS:
            return TelephonyManager.NETWORK_TYPE_UMTS;
        case ServiceState.RIL_RADIO_TECHNOLOGY_HSDPA:
            return TelephonyManager.NETWORK_TYPE_HSDPA;
        case ServiceState.RIL_RADIO_TECHNOLOGY_HSUPA:
            return TelephonyManager.NETWORK_TYPE_HSUPA;
        case ServiceState.RIL_RADIO_TECHNOLOGY_HSPA:
            return TelephonyManager.NETWORK_TYPE_HSPA;
        case ServiceState.RIL_RADIO_TECHNOLOGY_IS95A:
        case ServiceState.RIL_RADIO_TECHNOLOGY_IS95B:
            return TelephonyManager.NETWORK_TYPE_CDMA;
        case ServiceState.RIL_RADIO_TECHNOLOGY_1xRTT:
            return TelephonyManager.NETWORK_TYPE_1xRTT;
        case ServiceState.RIL_RADIO_TECHNOLOGY_EVDO_0:
            return TelephonyManager.NETWORK_TYPE_EVDO_0;
        case ServiceState.RIL_RADIO_TECHNOLOGY_EVDO_A:
            return TelephonyManager.NETWORK_TYPE_EVDO_A;
        case ServiceState.RIL_RADIO_TECHNOLOGY_EVDO_B:
            return TelephonyManager.NETWORK_TYPE_EVDO_B;
        case ServiceState.RIL_RADIO_TECHNOLOGY_EHRPD:
            return TelephonyManager.NETWORK_TYPE_EHRPD;
        case ServiceState.RIL_RADIO_TECHNOLOGY_LTE:
            return TelephonyManager.NETWORK_TYPE_LTE;
        case ServiceState.RIL_RADIO_TECHNOLOGY_HSPAP:
            return TelephonyManager.NETWORK_TYPE_HSPAP;
        case ServiceState.RIL_RADIO_TECHNOLOGY_GSM:
            return TelephonyManager.NETWORK_TYPE_GSM;
        case ServiceState.RIL_RADIO_TECHNOLOGY_TD_SCDMA:
            return TelephonyManager.NETWORK_TYPE_TD_SCDMA;
        case ServiceState.RIL_RADIO_TECHNOLOGY_IWLAN:
            return TelephonyManager.NETWORK_TYPE_IWLAN;
        case ServiceState.RIL_RADIO_TECHNOLOGY_LTE_CA:
            return TelephonyManager.NETWORK_TYPE_LTE_CA;
        default:
            return TelephonyManager.NETWORK_TYPE_UNKNOWN;
        }
    }