Ensure no thread leak after NetworkStatsServiceTest
This change includes:
1. A mechanism in DevSdkIngoreRunnrer to dump thread counts
before/after tests, and compare thread counts to detect leaks.
2. Add an annotation @MonitorThreadLeak for test classes to
annotate the classes which should monitor thread leaks.
3. Annotated NetworkStatsServiceTest to apply the enforcement.
Sample output:
[1/2] android.net.connectivity.com.android.server.net.NetworkStatsServiceTest#testDumpStatsMap: PASSED (1.187s)
[2/2] android.net.connectivity.com.android.server.net.NetworkStatsServiceTest#ThreadLeakMonitor: FAILED (7ms)
STACKTRACE:
java.lang.IllegalStateException: Expected threads: {binder:26055_3=1, Instr: androidx.test.runner.AndroidJUnitRunner=1, main=1, InstrumentationConnectionThread=1, binder:26055_2=1, binder:26055_1=1} but got: {binder:26055_3=1, NetworkStatsObservers=1, Instr: androidx.test.runner.AndroidJUnitRunner=1, main=1, InstrumentationConnectionThread=1, binder:26055_2=1, binder:26055_1=1}
Test: atest ConnectivityCoverageTests:android.net.connectivity.com.android.server.net.NetworkStatsServiceTest \
--rerun-until-failure 100
Bug: 308544001
Bug: 307693729
Change-Id: Ia0bccb82c5985df608b8402009b32626b6b17c5a
diff --git a/staticlibs/testutils/devicetests/com/android/testutils/DevSdkIgnoreRunner.kt b/staticlibs/testutils/devicetests/com/android/testutils/DevSdkIgnoreRunner.kt
index 2d281fd..1ba83ca 100644
--- a/staticlibs/testutils/devicetests/com/android/testutils/DevSdkIgnoreRunner.kt
+++ b/staticlibs/testutils/devicetests/com/android/testutils/DevSdkIgnoreRunner.kt
@@ -19,6 +19,7 @@
import androidx.test.ext.junit.runners.AndroidJUnit4
import com.android.testutils.DevSdkIgnoreRule.IgnoreAfter
import com.android.testutils.DevSdkIgnoreRule.IgnoreUpTo
+import java.lang.IllegalStateException
import java.lang.reflect.Modifier
import org.junit.runner.Description
import org.junit.runner.Runner
@@ -27,6 +28,7 @@
import org.junit.runner.manipulation.NoTestsRemainException
import org.junit.runner.manipulation.Sortable
import org.junit.runner.manipulation.Sorter
+import org.junit.runner.notification.Failure
import org.junit.runner.notification.RunNotifier
import org.junit.runners.Parameterized
@@ -52,6 +54,9 @@
* class MyTestClass { ... }
*/
class DevSdkIgnoreRunner(private val klass: Class<*>) : Runner(), Filterable, Sortable {
+ private val leakMonitorDesc = Description.createTestDescription(klass, "ThreadLeakMonitor")
+ private val shouldThreadLeakFailTest = klass.isAnnotationPresent(MonitorThreadLeak::class.java)
+
// Inference correctly infers Runner & Filterable & Sortable for |baseRunner|, but the
// Java bytecode doesn't have a way to express this. Give this type a name by wrapping it.
private class RunnerWrapper<T>(private val wrapped: T) :
@@ -61,6 +66,10 @@
override fun run(notifier: RunNotifier?) = wrapped.run(notifier)
}
+ // Annotation for test classes to indicate the test runner should monitor thread leak.
+ // TODO(b/307693729): Remove this annotation and monitor thread leak by default.
+ annotation class MonitorThreadLeak
+
private val baseRunner: RunnerWrapper<*>? = klass.let {
val ignoreAfter = it.getAnnotation(IgnoreAfter::class.java)
val ignoreUpTo = it.getAnnotation(IgnoreUpTo::class.java)
@@ -81,20 +90,52 @@
it.isAnnotationPresent(Parameterized.Parameters::class.java) }
override fun run(notifier: RunNotifier) {
- if (baseRunner != null) {
+ if (baseRunner == null) {
+ // Report a single, skipped placeholder test for this class, as the class is expected to
+ // report results when run. In practice runners that apply the Filterable implementation
+ // would see a NoTestsRemainException and not call the run method.
+ notifier.fireTestIgnored(
+ Description.createTestDescription(klass, "skippedClassForDevSdkMismatch"))
+ return
+ }
+ if (!shouldThreadLeakFailTest) {
baseRunner.run(notifier)
return
}
- // Report a single, skipped placeholder test for this class, as the class is expected to
- // report results when run. In practice runners that apply the Filterable implementation
- // would see a NoTestsRemainException and not call the run method.
- notifier.fireTestIgnored(
- Description.createTestDescription(klass, "skippedClassForDevSdkMismatch"))
+ // Dump threads as a baseline to monitor thread leaks.
+ val threadCountsBeforeTest = getAllThreadNameCounts()
+
+ baseRunner.run(notifier)
+
+ notifier.fireTestStarted(leakMonitorDesc)
+ val threadCountsAfterTest = getAllThreadNameCounts()
+ if (threadCountsBeforeTest != threadCountsAfterTest) {
+ notifier.fireTestFailure(Failure(leakMonitorDesc,
+ IllegalStateException("Expected threads: $threadCountsBeforeTest " +
+ "but got: $threadCountsAfterTest")))
+ }
+ notifier.fireTestFinished(leakMonitorDesc)
+ }
+
+ private fun getAllThreadNameCounts(): Map<String, Int> {
+ // Get the counts of threads in the group per name.
+ // Filter system thread groups.
+ return Thread.getAllStackTraces().keys
+ .filter { it.threadGroup?.name != "system" }
+ .groupingBy { it.name }.eachCount()
}
override fun getDescription(): Description {
- return baseRunner?.description ?: Description.createSuiteDescription(klass)
+ if (baseRunner == null) {
+ return Description.createSuiteDescription(klass)
+ }
+
+ return baseRunner.description.also {
+ if (shouldThreadLeakFailTest) {
+ it.addChild(leakMonitorDesc)
+ }
+ }
}
/**
@@ -102,7 +143,9 @@
*/
override fun testCount(): Int {
// When ignoring the tests, a skipped placeholder test is reported, so test count is 1.
- return baseRunner?.testCount() ?: 1
+ if (baseRunner == null) return 1
+
+ return baseRunner.testCount() + if (shouldThreadLeakFailTest) 1 else 0
}
@Throws(NoTestsRemainException::class)
diff --git a/tests/unit/java/com/android/server/net/NetworkStatsServiceTest.java b/tests/unit/java/com/android/server/net/NetworkStatsServiceTest.java
index 92a5b64..7a4dfed 100644
--- a/tests/unit/java/com/android/server/net/NetworkStatsServiceTest.java
+++ b/tests/unit/java/com/android/server/net/NetworkStatsServiceTest.java
@@ -193,6 +193,7 @@
* TODO: This test used to be really brittle because it used Easymock - it uses Mockito now, but
* still uses the Easymock structure, which could be simplified.
*/
+@DevSdkIgnoreRunner.MonitorThreadLeak
@RunWith(DevSdkIgnoreRunner.class)
@SmallTest
// NetworkStatsService is not updatable before T, so tests do not need to be backwards compatible