Hold Display Suspend blocker when going to Doze
The transition to Doze is asynchronous from the release of the display
suspend blocker. This created a race condition where we could
potentially suspend before Doze service had a chance to transition to
Doze. This change holds the Display Suspend blocker until Doze service
acquires the DOZE lock.
Bug: 138828701
Test: atest PowerManagerService
Test: Manual, verify no repro of the bug. Additional verify the device
does release the Display suspend blocker once we are in DOZE.
Change-Id: I777bc7963b1ab445378164b0f4d3f79113510b81
diff --git a/services/core/java/com/android/server/power/PowerManagerService.java b/services/core/java/com/android/server/power/PowerManagerService.java
index aa49ba6..e1b3e4d 100644
--- a/services/core/java/com/android/server/power/PowerManagerService.java
+++ b/services/core/java/com/android/server/power/PowerManagerService.java
@@ -542,6 +542,10 @@
// True if we in the process of performing a forceSuspend
private boolean mForceSuspendActive;
+ // Transition to Doze is in progress. We have transitioned to WAKEFULNESS_DOZING,
+ // but the DreamService has not yet been told to start (it's an async process).
+ private boolean mDozeStartInProgress;
+
private final class ForegroundProfileObserver extends SynchronousUserSwitchObserver {
@Override
public void onUserSwitching(int newUserId) throws RemoteException {}
@@ -1514,6 +1518,7 @@
mLastSleepTime = eventTime;
mLastSleepReason = reason;
mSandmanSummoned = true;
+ mDozeStartInProgress = true;
setWakefulnessLocked(WAKEFULNESS_DOZING, reason, eventTime);
// Report the number of wake locks that will be cleared by going to sleep.
@@ -1601,6 +1606,10 @@
mWakefulness = wakefulness;
mWakefulnessChanging = true;
mDirty |= DIRTY_WAKEFULNESS;
+
+ // This is only valid while we are in wakefulness dozing. Set to false otherwise.
+ mDozeStartInProgress &= (mWakefulness == WAKEFULNESS_DOZING);
+
if (mNotifier != null) {
mNotifier.onWakefulnessChangeStarted(wakefulness, reason, eventTime);
}
@@ -1631,6 +1640,9 @@
if (mWakefulness == WAKEFULNESS_DOZING
&& (mWakeLockSummary & WAKE_LOCK_DOZE) == 0) {
return; // wait until dream has enabled dozing
+ } else {
+ // Doze wakelock acquired (doze started) or device is no longer dozing.
+ mDozeStartInProgress = false;
}
if (mWakefulness == WAKEFULNESS_DOZING || mWakefulness == WAKEFULNESS_ASLEEP) {
logSleepTimeoutRecapturedLocked();
@@ -2309,6 +2321,10 @@
isDreaming = false;
}
+ // At this point, we either attempted to start the dream or no attempt will be made,
+ // so stop holding the display suspend blocker for Doze.
+ mDozeStartInProgress = false;
+
// Update dream state.
synchronized (mLock) {
// Remember the initial battery level when the dream started.
@@ -2735,6 +2751,16 @@
if (mScreenBrightnessBoostInProgress) {
return true;
}
+
+ // When we transition to DOZING, we have to keep the display suspend blocker
+ // up until the Doze service has a change to acquire the DOZE wakelock.
+ // Here we wait for mWakefulnessChanging to become false since the wakefulness
+ // transition to DOZING isn't considered "changed" until the doze wake lock is
+ // acquired.
+ if (mWakefulness == WAKEFULNESS_DOZING && mDozeStartInProgress) {
+ return true;
+ }
+
// Let the system suspend if the screen is off or dozing.
return false;
}
