diff options
| -rw-r--r-- | services/core/java/com/android/server/AlarmManagerService.java | 84 |
1 files changed, 22 insertions, 62 deletions
diff --git a/services/core/java/com/android/server/AlarmManagerService.java b/services/core/java/com/android/server/AlarmManagerService.java index ed8bc51f0de9..554393af3052 100644 --- a/services/core/java/com/android/server/AlarmManagerService.java +++ b/services/core/java/com/android/server/AlarmManagerService.java @@ -61,7 +61,6 @@ import java.util.Date; import java.util.HashMap; import java.util.LinkedList; import java.util.Locale; -import java.util.Random; import java.util.TimeZone; import static android.app.AlarmManager.RTC_WAKEUP; @@ -109,12 +108,8 @@ class AlarmManagerService extends SystemService { final Object mLock = new Object(); long mNativeData; - - private final Random mFuzzer = new Random(); - private long mNextWakeupBatchStart; // nominal start of next wakeup's delivery window - private long mNextWakeup; // actual scheduled next wakeup within that window + private long mNextWakeup; private long mNextNonWakeup; - int mBroadcastRefCount = 0; PowerManager.WakeLock mWakeLock; boolean mLastWakeLockUnimportantForLogging; @@ -366,27 +361,14 @@ class AlarmManagerService extends SystemService { static class BatchTimeOrder implements Comparator<Batch> { public int compare(Batch b1, Batch b2) { - final long start1 = b1.start; - final long start2 = b2.start; - if (start1 > start2) { - return 1; - } - if (start1 < start2) { - return -1; - } - - // Identical trigger times. As a secondary ordering, require that - // the batch with the shorter allowable delivery window sorts first. - final long interval1 = b1.end - b1.start; - final long interval2 = b2.end - b2.start; - if (interval1 > interval2) { + long when1 = b1.start; + long when2 = b2.start; + if (when1 - when2 > 0) { return 1; } - if (interval2 < interval1) { + if (when1 - when2 < 0) { return -1; } - - // equal start + delivery window => they're identical return 0; } } @@ -609,7 +591,7 @@ class AlarmManagerService extends SystemService { @Override public void onStart() { mNativeData = init(); - mNextWakeup = mNextWakeupBatchStart = mNextNonWakeup = 0; + mNextWakeup = mNextNonWakeup = 0; // We have to set current TimeZone info to kernel // because kernel doesn't keep this after reboot @@ -804,7 +786,6 @@ class AlarmManagerService extends SystemService { "AlarmManager.set"); } - // Exact alarms are standalone; inexact get batched together setImpl(type, triggerAtTime, windowLength, interval, operation, windowLength == AlarmManager.WINDOW_EXACT, workSource, alarmClock); } @@ -877,7 +858,7 @@ class AlarmManagerService extends SystemService { pw.print("nowRTC="); pw.print(nowRTC); pw.print("="); pw.print(sdf.format(new Date(nowRTC))); - pw.print(" nowELAPSED="); pw.print(nowELAPSED); + pw.print(" nowELAPSED="); TimeUtils.formatDuration(nowELAPSED, pw); pw.println(); if (!mInteractive) { pw.print("Time since non-interactive: "); @@ -1083,6 +1064,17 @@ class AlarmManagerService extends SystemService { return true; } + private Batch findFirstWakeupBatchLocked() { + final int N = mAlarmBatches.size(); + for (int i = 0; i < N; i++) { + Batch b = mAlarmBatches.get(i); + if (b.hasWakeups()) { + return b; + } + } + return null; + } + private AlarmManager.AlarmClockInfo getNextAlarmClockImpl(int userId) { synchronized (mLock) { return mNextAlarmClockForUser.get(userId); @@ -1216,48 +1208,16 @@ class AlarmManagerService extends SystemService { // prior to that which contains no wakeups, we schedule that as well. long nextNonWakeup = 0; if (mAlarmBatches.size() > 0) { - // Find the first wakeup alarm and note the following batch as well. We'll be - // choosing a fuzzed delivery time within the first's allowable interval but - // ensuring that it does not encroach on the second's start time, to minimize - // alarm reordering. - Batch firstWakeup = null, nextAfterWakeup = null; - final int N = mAlarmBatches.size(); - for (int i = 0; i < N; i++) { - Batch b = mAlarmBatches.get(i); - if (b.hasWakeups()) { - firstWakeup = b; - if (i < N-1) { - nextAfterWakeup = mAlarmBatches.get(i+1); - } - break; - } - } - - // There's a subtlety here: we depend on the invariant that if two batches - // exist with the same start time, the one with the shorter delivery window - // is sorted before the other. This guarantees us that we need only look - // at the first [relevant] batch in the queue in order to schedule an alarm - // appropriately. + final Batch firstWakeup = findFirstWakeupBatchLocked(); final Batch firstBatch = mAlarmBatches.get(0); - if (firstWakeup != null && mNextWakeupBatchStart != firstWakeup.start) { - mNextWakeupBatchStart = mNextWakeup = firstWakeup.start; - final long windowEnd = (nextAfterWakeup == null) - ? firstWakeup.end - : Math.min(firstWakeup.end, nextAfterWakeup.start); - final long interval = windowEnd - firstWakeup.start; - // if the interval is over maxint we're into crazy land anyway, but - // just in case we check and don't fuzz if the conversion to int for - // random-number purposes would blow up - if (interval > 0 && interval < Integer.MAX_VALUE) { - mNextWakeup += mFuzzer.nextInt((int) interval); - } - setLocked(ELAPSED_REALTIME_WAKEUP, mNextWakeup); + if (firstWakeup != null && mNextWakeup != firstWakeup.start) { + mNextWakeup = firstWakeup.start; + setLocked(ELAPSED_REALTIME_WAKEUP, firstWakeup.start); } if (firstBatch != firstWakeup) { nextNonWakeup = firstBatch.start; } } - if (mPendingNonWakeupAlarms.size() > 0) { if (nextNonWakeup == 0 || mNextNonWakeupDeliveryTime < nextNonWakeup) { nextNonWakeup = mNextNonWakeupDeliveryTime; |