Track client requests through location manager.

This fixes a problem where applications could ask the location
manager to do very heavy-weight things (like...  say... update
location every minute), which would get accounted against the
system instead of the application because ultimately it is the
system making the heavy calls (wake locks, etc).

To solve this, we introduce a new class WorkSource representing
the source of some work.  Wake locks and Wifi locks allow you
to set the source to use (but only if you are system code and thus
can get the permission to do so), which is what will be reported
to the battery stats until the actual caller.

For the initial implementation, the location manager keeps track
of all clients requesting periodic updates, and tells its providers
about them as a WorkSource param when setting their min update time.
The network location provider uses this to set the source on the
wake and wifi locks it acquires, when doing work because of the
update period.

This should also be used elsewhere, such as in the GPS provider,
but this is a good start.

Change-Id: I2b6ffafad9e90ecf15d7c502e2db675fd52ae3cf

1 files changed, 23 insertions, 4 deletions

diff --git a/services/java/com/android/server/LocationManagerService.java b/services/java/com/android/server/LocationManagerService.java
index a38970f..f3ce8ba 100644
--- a/services/java/com/android/server/LocationManagerService.java
+++ b/services/java/com/android/server/LocationManagerService.java
@@ -52,6 +52,7 @@ import android.os.Message;
 import android.os.PowerManager;
 import android.os.Process;
 import android.os.RemoteException;
+import android.os.WorkSource;
 import android.provider.Settings;
 import android.util.Log;
 import android.util.Slog;
@@ -157,6 +158,12 @@ public class LocationManagerService extends ILocationManager.Stub implements Run
     private final HashMap<String,ArrayList<UpdateRecord>> mRecordsByProvider =
         new HashMap<String,ArrayList<UpdateRecord>>();
 
+    /**
+     * Temporary filled in when computing min time for a provider.  Access is
+     * protected by global lock mLock.
+     */
+    private final WorkSource mTmpWorkSource = new WorkSource();
+
     // Proximity listeners
     private Receiver mProximityReceiver = null;
     private ILocationListener mProximityListener = null;
@@ -912,7 +919,7 @@ public class LocationManagerService extends ILocationManager.Stub implements Run
         if (enabled) {
             p.enable();
             if (listeners > 0) {
-                p.setMinTime(getMinTimeLocked(provider));
+                p.setMinTime(getMinTimeLocked(provider), mTmpWorkSource);
                 p.enableLocationTracking(true);
             }
         } else {
@@ -924,9 +931,21 @@ public class LocationManagerService extends ILocationManager.Stub implements Run
     private long getMinTimeLocked(String provider) {
         long minTime = Long.MAX_VALUE;
         ArrayList<UpdateRecord> records = mRecordsByProvider.get(provider);
+        mTmpWorkSource.clear();
         if (records != null) {
             for (int i=records.size()-1; i>=0; i--) {
-                minTime = Math.min(minTime, records.get(i).mMinTime);
+                UpdateRecord ur = records.get(i);
+                long curTime = ur.mMinTime;
+                if (curTime < minTime) {
+                    minTime = curTime;
+                }
+            }
+            long inclTime = (minTime*3)/2;
+            for (int i=records.size()-1; i>=0; i--) {
+                UpdateRecord ur = records.get(i);
+                if (ur.mMinTime <= inclTime) {
+                    mTmpWorkSource.add(ur.mUid);
+                }
             }
         }
         return minTime;
@@ -1124,7 +1143,7 @@ public class LocationManagerService extends ILocationManager.Stub implements Run
             boolean isProviderEnabled = isAllowedBySettingsLocked(provider);
             if (isProviderEnabled) {
                 long minTimeForProvider = getMinTimeLocked(provider);
-                p.setMinTime(minTimeForProvider);
+                p.setMinTime(minTimeForProvider, mTmpWorkSource);
                 // try requesting single shot if singleShot is true, and fall back to
                 // regular location tracking if requestSingleShotFix() is not supported
                 if (!singleShot || !p.requestSingleShotFix()) {
@@ -1222,7 +1241,7 @@ public class LocationManagerService extends ILocationManager.Stub implements Run
                 LocationProviderInterface p = mProvidersByName.get(provider);
                 if (p != null) {
                     if (hasOtherListener) {
-                        p.setMinTime(getMinTimeLocked(provider));
+                        p.setMinTime(getMinTimeLocked(provider), mTmpWorkSource);
                     } else {
                         p.enableLocationTracking(false);
                     }