Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit f602d362 authored by Mike Lockwood's avatar Mike Lockwood
Browse files

GPS: remove GpsEventThread from GpsLocationProvider 



Rather than polling for events from the native code in an event thread,
we now require the GPS HAL libraries to call our callbacks from a thread
that is registered with the JVM to call directly into Java.
This eliminates a thread from our code and removes one step in the chain
of message passing from the GPS to the Location Manager client.

Change-Id: I2745a157690310ba9a699a8369f54a7366c6b1ba
Signed-off-by: default avatarMike Lockwood <lockwood@android.com>
parent 07ccf5ad

core/jni/AndroidRuntime.cpp

+4 −2
Original line number Diff line number Diff line
@@ -1136,11 +1136,13 @@ static int javaDetachThread(void) 
 *

 * This is called from elsewhere in the library.

 */

/*static*/ void AndroidRuntime::createJavaThread(const char* name,

/*static*/ android_thread_id_t AndroidRuntime::createJavaThread(const char* name,

    void (*start)(void *), void* arg)

{

    android_thread_id_t threadId = 0;

    javaCreateThreadEtc((android_thread_func_t) start, arg, name,

        ANDROID_PRIORITY_DEFAULT, 0, NULL);

        ANDROID_PRIORITY_DEFAULT, 0, &threadId);

    return threadId;

}



#if 0

include/android_runtime/AndroidRuntime.h

+1 −1
Original line number Diff line number Diff line
@@ -87,7 +87,7 @@ public: 
    virtual void onExit(int code);



    /** create a new thread that is visible from Java */

    static void createJavaThread(const char* name, void (*start)(void *),

    static android_thread_id_t createJavaThread(const char* name, void (*start)(void *),

        void* arg);



    /** return a pointer to the VM running in this process */

services/java/com/android/server/location/GpsLocationProvider.java

+3 −53
Original line number Diff line number Diff line
@@ -226,8 +226,6 @@ public class GpsLocationProvider implements LocationProviderInterface { 
    private Handler mHandler;

    // Used to signal when our main thread has initialized everything

    private final CountDownLatch mInitializedLatch = new CountDownLatch(1);

    // Thread for receiving events from the native code

    private Thread mEventThread;



    private String mAGpsApn;

    private int mAGpsDataConnectionState;
@@ -643,10 +641,6 @@ public class GpsLocationProvider implements LocationProviderInterface { 
            if (mC2KServerHost != null) {

                native_set_agps_server(AGPS_TYPE_C2K, mC2KServerHost, mC2KServerPort);

            }



            // run event listener thread while we are enabled

            mEventThread = new GpsEventThread();

            mEventThread.start();

        } else {

            Log.w(TAG, "Failed to enable location provider");

        }
@@ -669,29 +663,9 @@ public class GpsLocationProvider implements LocationProviderInterface { 


        mEnabled = false;

        stopNavigating();

        native_disable();



        // make sure our event thread exits

        if (mEventThread != null) {

            try {

                mEventThread.join();

            } catch (InterruptedException e) {

                Log.w(TAG, "InterruptedException when joining mEventThread");

            }

            mEventThread = null;

        }



        // do this before releasing wakelock

        native_cleanup();



        // The GpsEventThread does not wait for the GPS to shutdown

        // so we need to report the GPS_STATUS_ENGINE_OFF event here

        if (mNavigating) {

            reportStatus(GPS_STATUS_SESSION_END);

        }

        if (mEngineOn) {

            reportStatus(GPS_STATUS_ENGINE_OFF);

        }

    }



    public boolean isEnabled() {
@@ -1231,12 +1205,12 @@ public class GpsLocationProvider implements LocationProviderInterface { 
    /**

     * called from native code to report NMEA data received

     */

    private void reportNmea(int index, long timestamp) {

    private void reportNmea(long timestamp) {

        synchronized(mListeners) {

            int size = mListeners.size();

            if (size > 0) {

                // don't bother creating the String if we have no listeners

                int length = native_read_nmea(index, mNmeaBuffer, mNmeaBuffer.length);

                int length = native_read_nmea(mNmeaBuffer, mNmeaBuffer.length);

                String nmea = new String(mNmeaBuffer, 0, length);



                for (int i = 0; i < size; i++) {
@@ -1359,28 +1333,6 @@ public class GpsLocationProvider implements LocationProviderInterface { 
		mNIHandler.handleNiNotification(notification);		

	}



    // this thread is used to receive events from the native code.

    // native_wait_for_event() will callback to us via reportLocation(), reportStatus(), etc.

    // this is necessary because native code cannot call Java on a thread that the JVM does

    // not know about.

    private final class GpsEventThread extends Thread {



        public GpsEventThread() {

            super("GpsEventThread");

        }



        public void run() {

            if (DEBUG) Log.d(TAG, "GpsEventThread starting");

            // Exit as soon as disable() is called instead of waiting for the GPS to stop.

            while (mEnabled) {

                // this will wait for an event from the GPS,

                // which will be reported via reportLocation or reportStatus

                native_wait_for_event();

            }

            if (DEBUG) Log.d(TAG, "GpsEventThread exiting");

        }

    }



    private void sendMessage(int message, int arg, Object obj) {

        // hold a wake lock while messages are pending

        synchronized (mWakeLock) {
@@ -1485,19 +1437,17 @@ public class GpsLocationProvider implements LocationProviderInterface { 
    private static native boolean native_is_supported();



    private native boolean native_init();

    private native void native_disable();

    private native void native_cleanup();

    private native boolean native_set_position_mode(int mode, int recurrence, int min_interval,

            int preferred_accuracy, int preferred_time);

    private native boolean native_start();

    private native boolean native_stop();

    private native void native_delete_aiding_data(int flags);

    private native void native_wait_for_event();

    // returns number of SVs

    // mask[0] is ephemeris mask and mask[1] is almanac mask

    private native int native_read_sv_status(int[] svs, float[] snrs,

            float[] elevations, float[] azimuths, int[] masks);

    private native int native_read_nmea(int index, byte[] buffer, int bufferSize);

    private native int native_read_nmea(byte[] buffer, int bufferSize);

    private native void native_inject_location(double latitude, double longitude, float accuracy);



    // XTRA Support

services/jni/com_android_server_location_GpsLocationProvider.cpp

+124 −233

File changed.

Preview size limit exceeded, changes collapsed.