Eliminate unnecessary object churn in job scheduler updating

am: eafb535072

Change-Id: I4b43ea727720e73ad11a0615c221fe23ca9d34c0

services/core/java/com/android/server/job/JobSchedulerService.java

@@ -907,7 +907,11 @@ public final class JobSchedulerService extends com.android.server.SystemService
     private boolean isCurrentlyActiveLocked(JobStatus job) {
         for (int i=0; i<mActiveServices.size(); i++) {
             JobServiceContext serviceContext = mActiveServices.get(i);
-            final JobStatus running = serviceContext.getRunningJob();
+            // The 'unsafe' direct-internal-reference running-job inspector is okay to
+            // use here because we are already holding the necessary lock *and* we
+            // immediately discard the returned object reference, if any; we return
+            // only a boolean state indicator to the caller.
+            final JobStatus running = serviceContext.getRunningJobUnsafeLocked();
             if (running != null && running.matches(job.getUid(), job.getJobId())) {
                 return true;
             }

services/core/java/com/android/server/job/JobServiceContext.java

@@ -230,6 +230,15 @@ public class JobServiceContext extends IJobCallback.Stub implements ServiceConne
         return job == null ? null : new JobStatus(job);
     }
 
+    /**
+     * Internal non-cloning inspection of the currently running job, if any.  The lock
+     * must be held when calling this *and* for the entire lifetime of using its returned
+     * JobStatus object!
+     */
+    JobStatus getRunningJobUnsafeLocked() {
+        return mRunningJob;
+    }
+
     /** Called externally when a job that was scheduled for execution should be cancelled. */
     void cancelExecutingJob(int reason) {
         mCallbackHandler.obtainMessage(MSG_CANCEL, reason, 0 /* unused */).sendToTarget();