Serialize PowerStatsExporter sessions
There is a chance of a race condition if multiple passes
over PowerStatsExporter are done at the same time.
Bug: 355359427
Test: atest PowerStatsTests; atest PowerStatsTestsRavenwood
Flag: EXEMPT bugfix
Change-Id: I691843dc9a1f6597467a4c5984386a623e7233d8
diff --git a/services/core/java/com/android/server/power/stats/PowerStatsExporter.java b/services/core/java/com/android/server/power/stats/PowerStatsExporter.java
index 39954b8..5f41090 100644
--- a/services/core/java/com/android/server/power/stats/PowerStatsExporter.java
+++ b/services/core/java/com/android/server/power/stats/PowerStatsExporter.java
@@ -59,58 +59,61 @@
*/
public void exportAggregatedPowerStats(BatteryUsageStats.Builder batteryUsageStatsBuilder,
long monotonicStartTime, long monotonicEndTime) {
- boolean hasStoredSpans = false;
- long maxEndTime = monotonicStartTime;
- List<PowerStatsSpan.Metadata> spans = mPowerStatsStore.getTableOfContents();
- for (int i = spans.size() - 1; i >= 0; i--) {
- PowerStatsSpan.Metadata metadata = spans.get(i);
- if (!metadata.getSections().contains(AggregatedPowerStatsSection.TYPE)) {
- continue;
- }
-
- List<PowerStatsSpan.TimeFrame> timeFrames = metadata.getTimeFrames();
- long spanMinTime = Long.MAX_VALUE;
- long spanMaxTime = Long.MIN_VALUE;
- for (int j = 0; j < timeFrames.size(); j++) {
- PowerStatsSpan.TimeFrame timeFrame = timeFrames.get(j);
- long startMonotonicTime = timeFrame.startMonotonicTime;
- long endMonotonicTime = startMonotonicTime + timeFrame.duration;
- if (startMonotonicTime < spanMinTime) {
- spanMinTime = startMonotonicTime;
+ synchronized (this) {
+ boolean hasStoredSpans = false;
+ long maxEndTime = monotonicStartTime;
+ List<PowerStatsSpan.Metadata> spans = mPowerStatsStore.getTableOfContents();
+ for (int i = spans.size() - 1; i >= 0; i--) {
+ PowerStatsSpan.Metadata metadata = spans.get(i);
+ if (!metadata.getSections().contains(AggregatedPowerStatsSection.TYPE)) {
+ continue;
}
- if (endMonotonicTime > spanMaxTime) {
- spanMaxTime = endMonotonicTime;
+
+ List<PowerStatsSpan.TimeFrame> timeFrames = metadata.getTimeFrames();
+ long spanMinTime = Long.MAX_VALUE;
+ long spanMaxTime = Long.MIN_VALUE;
+ for (int j = 0; j < timeFrames.size(); j++) {
+ PowerStatsSpan.TimeFrame timeFrame = timeFrames.get(j);
+ long startMonotonicTime = timeFrame.startMonotonicTime;
+ long endMonotonicTime = startMonotonicTime + timeFrame.duration;
+ if (startMonotonicTime < spanMinTime) {
+ spanMinTime = startMonotonicTime;
+ }
+ if (endMonotonicTime > spanMaxTime) {
+ spanMaxTime = endMonotonicTime;
+ }
+ }
+
+ if (!(spanMinTime >= monotonicStartTime && spanMaxTime < monotonicEndTime)) {
+ continue;
+ }
+
+ if (spanMaxTime > maxEndTime) {
+ maxEndTime = spanMaxTime;
+ }
+
+ PowerStatsSpan span = mPowerStatsStore.loadPowerStatsSpan(metadata.getId(),
+ AggregatedPowerStatsSection.TYPE);
+ if (span == null) {
+ Slog.e(TAG, "Could not read PowerStatsStore section " + metadata);
+ continue;
+ }
+ List<PowerStatsSpan.Section> sections = span.getSections();
+ for (int k = 0; k < sections.size(); k++) {
+ hasStoredSpans = true;
+ PowerStatsSpan.Section section = sections.get(k);
+ populateBatteryUsageStatsBuilder(batteryUsageStatsBuilder,
+ ((AggregatedPowerStatsSection) section).getAggregatedPowerStats());
}
}
- if (!(spanMinTime >= monotonicStartTime && spanMaxTime < monotonicEndTime)) {
- continue;
+ if (!hasStoredSpans
+ || maxEndTime < monotonicEndTime - mBatterySessionTimeSpanSlackMillis) {
+ mPowerStatsAggregator.aggregatePowerStats(maxEndTime, monotonicEndTime,
+ stats -> populateBatteryUsageStatsBuilder(batteryUsageStatsBuilder, stats));
}
-
- if (spanMaxTime > maxEndTime) {
- maxEndTime = spanMaxTime;
- }
-
- PowerStatsSpan span = mPowerStatsStore.loadPowerStatsSpan(metadata.getId(),
- AggregatedPowerStatsSection.TYPE);
- if (span == null) {
- Slog.e(TAG, "Could not read PowerStatsStore section " + metadata);
- continue;
- }
- List<PowerStatsSpan.Section> sections = span.getSections();
- for (int k = 0; k < sections.size(); k++) {
- hasStoredSpans = true;
- PowerStatsSpan.Section section = sections.get(k);
- populateBatteryUsageStatsBuilder(batteryUsageStatsBuilder,
- ((AggregatedPowerStatsSection) section).getAggregatedPowerStats());
- }
+ mPowerStatsAggregator.reset();
}
-
- if (!hasStoredSpans || maxEndTime < monotonicEndTime - mBatterySessionTimeSpanSlackMillis) {
- mPowerStatsAggregator.aggregatePowerStats(maxEndTime, monotonicEndTime,
- stats -> populateBatteryUsageStatsBuilder(batteryUsageStatsBuilder, stats));
- }
- mPowerStatsAggregator.reset();
}
private void populateBatteryUsageStatsBuilder(