Merge "Dump stack trace without holding the global lock in Watchdog" into sc-dev (298bb6c1) · Commits · e / os / android_frameworks_base

services/core/java/com/android/server/Watchdog.java

+28 −18

Original line number	Diff line number	Diff line
		@@ -56,6 +56,7 @@ import java.io.IOException;
		import java.io.StringWriter;
		import java.util.ArrayList;
		import java.util.Arrays;
		import java.util.Collections;
		import java.util.HashSet;
		import java.util.List;
		import java.util.concurrent.TimeUnit;
		@@ -585,10 +586,12 @@ public class Watchdog {
		private void run() {
		boolean waitedHalf = false;
		while (true) {
		final List<HandlerChecker> blockedCheckers;
		final String subject;
		final boolean allowRestart;
		List<HandlerChecker> blockedCheckers = Collections.emptyList();
		String subject = "";
		boolean allowRestart = true;
		int debuggerWasConnected = 0;
		boolean doWaitedHalfDump = false;
		final ArrayList<Integer> pids;
		synchronized (mLock) {
		long timeout = CHECK_INTERVAL;
		// Make sure we (re)spin the checkers that have become idle within
		@@ -634,20 +637,28 @@ public class Watchdog {
		} else if (waitState == WAITED_HALF) {
		if (!waitedHalf) {
		Slog.i(TAG, "WAITED_HALF");
		// We've waited half the deadlock-detection interval. Pull a stack
		// trace and wait another half.
		ArrayList<Integer> pids = new ArrayList<>(mInterestingJavaPids);
		ActivityManagerService.dumpStackTraces(pids, null, null,
		getInterestingNativePids(), null);
		waitedHalf = true;
		}
		// We've waited half, but we'd need to do the stack trace dump w/o the lock.
		pids = new ArrayList<>(mInterestingJavaPids);
		doWaitedHalfDump = true;
		} else {
		continue;
		}

		} else {
		// something is overdue!
		blockedCheckers = getBlockedCheckersLocked();
		subject = describeCheckersLocked(blockedCheckers);
		allowRestart = mAllowRestart;
		pids = new ArrayList<>(mInterestingJavaPids);
		}
		} // END synchronized (mLock)

		if (doWaitedHalfDump) {
		// We've waited half the deadlock-detection interval. Pull a stack
		// trace and wait another half.
		ActivityManagerService.dumpStackTraces(pids, null, null,
		getInterestingNativePids(), null);
		continue;
		}

		// If we got here, that means that the system is most likely hung.
		@@ -655,8 +666,6 @@ public class Watchdog {
		// Then kill this process so that the system will restart.
		EventLog.writeEvent(EventLogTags.WATCHDOG, subject);

		ArrayList<Integer> pids = new ArrayList<>(mInterestingJavaPids);

		long anrTime = SystemClock.uptimeMillis();
		StringBuilder report = new StringBuilder();
		report.append(MemoryPressureUtil.currentPsiState());
		@@ -681,6 +690,7 @@ public class Watchdog {
		// Try to add the error to the dropbox, but assuming that the ActivityManager
		// itself may be deadlocked. (which has happened, causing this statement to
		// deadlock and the watchdog as a whole to be ineffective)
		final String localSubject = subject;
		Thread dropboxThread = new Thread("watchdogWriteToDropbox") {
		public void run() {
		// If a watched thread hangs before init() is called, we don't have a
		@@ -688,10 +698,10 @@ public class Watchdog {
		if (mActivity != null) {
		mActivity.addErrorToDropBox(
		"watchdog", null, "system_server", null, null, null,
		subject, report.toString(), stack, null, null, null);
		localSubject, report.toString(), stack, null, null, null);
		}
		FrameworkStatsLog.write(FrameworkStatsLog.SYSTEM_SERVER_WATCHDOG_OCCURRED,
		subject);
		localSubject);
		}
		};
		dropboxThread.start();