Merge "Resolve Thread Visibility Issue in... (52f45340) · Commits · e / os / android_frameworks_base

services/core/java/com/android/server/am/ProcessErrorStateRecord.java

+12 −3

Original line number	Diff line number	Diff line
		@@ -51,11 +51,11 @@ import android.util.SparseBooleanArray;
		import com.android.internal.annotations.CompositeRWLock;
		import com.android.internal.annotations.GuardedBy;
		import com.android.internal.annotations.VisibleForTesting;
		import com.android.modules.expresslog.Counter;
		import com.android.internal.os.ProcessCpuTracker;
		import com.android.internal.os.TimeoutRecord;
		import com.android.internal.os.anr.AnrLatencyTracker;
		import com.android.internal.util.FrameworkStatsLog;
		import com.android.modules.expresslog.Counter;
		import com.android.server.ResourcePressureUtil;
		import com.android.server.criticalevents.CriticalEventLog;
		import com.android.server.stats.pull.ProcfsMemoryUtil.MemorySnapshot;
		@@ -456,6 +456,11 @@ class ProcessErrorStateRecord {
		String currentPsiState = ResourcePressureUtil.currentPsiState();
		latencyTracker.currentPsiStateReturned();
		report.append(currentPsiState);
		// The 'processCpuTracker' variable is a shared resource that might be initialized and
		// updated in a different thread. In order to prevent thread visibility issues, which
		// can occur when one thread does not immediately see the changes made to
		// 'processCpuTracker' by another thread, it is necessary to use synchronization whenever
		// 'processCpuTracker' is accessed or modified.
		ProcessCpuTracker processCpuTracker = new ProcessCpuTracker(true);

		// We push the native pids collection task to the helper thread through
		@@ -517,12 +522,16 @@ class ProcessErrorStateRecord {
		}
		mService.updateCpuStatsNow();
		mService.mAppProfiler.printCurrentCpuState(report, anrTime);
		synchronized (processCpuTracker) {
		info.append(processCpuTracker.printCurrentLoad());
		}
		info.append(report);
		}
		report.append(tracesFileException.getBuffer());

		synchronized (processCpuTracker) {
		info.append(processCpuTracker.printCurrentState(anrTime));
		}

		Slog.e(TAG, info.toString());
		if (tracesFile == null) {

services/core/java/com/android/server/am/StackTracesDumpHelper.java

+18 −15

Original line number	Diff line number	Diff line
		@@ -464,14 +464,16 @@ public class StackTracesDumpHelper {
		latencyTracker.processCpuTrackerMethodsCalled();
		}
		ArrayList<Integer> extraPids = new ArrayList<>();
		synchronized (processCpuTracker) {
		processCpuTracker.init();
		}
		try {
		Thread.sleep(200);
		} catch (InterruptedException ignored) {
		}

		synchronized (processCpuTracker) {
		processCpuTracker.update();

		// We'll take the stack crawls of just the top apps using CPU.
		final int workingStatsNumber = processCpuTracker.countWorkingStats();
		for (int i = 0; i < workingStatsNumber && extraPids.size() < 2; i++) {
		@@ -488,6 +490,7 @@ public class StackTracesDumpHelper {
		+ stats.pid);
		}
		}
		}
		if (latencyTracker != null) {
		latencyTracker.processCpuTrackerMethodsReturned();
		}