Merge pull request #19029 from dmitripivkine/0.44

(0.44)Add missed scan for modules in System and Application class loaders

Author: pshipton

runtime/gc_base/RootScanner.cpp

@@ -395,44 +395,44 @@ MM_RootScanner::scanPermanentClasses(MM_EnvironmentBase *env)
 {
 	reportScanningStarted(RootScannerEntity_PermanentClasses);
 
+	/* Do systemClassLoader */
+	scanClassloader(env, static_cast<J9JavaVM*>(_omrVM->_language_vm)->systemClassLoader);
+
+	/* Do applicationClassLoader */
+	scanClassloader(env, static_cast<J9JavaVM*>(_omrVM->_language_vm)->applicationClassLoader);
+
+	condYield();
+
+	reportScanningEnded(RootScannerEntity_PermanentClasses);
+}
+
+/**
+ * Scan all objects from class loader.
+ */
+void
+MM_RootScanner::scanClassloader(MM_EnvironmentBase *env, J9ClassLoader *classLoader)
+{
 	J9MemorySegment *segment = NULL;
 	J9Class *clazz = NULL;
 
-	/* Do systemClassLoader */
-	if (NULL != static_cast<J9JavaVM*>(_omrVM->_language_vm)->systemClassLoader) {
-		GC_ClassLoaderSegmentIterator segmentIterator(static_cast<J9JavaVM*>(_omrVM->_language_vm)->systemClassLoader, MEMORY_TYPE_RAM_CLASS);
-		while(NULL != (segment = segmentIterator.nextSegment())) {
-			if(_singleThread || J9MODRON_HANDLE_NEXT_WORK_UNIT(env)) {
+	if (NULL != classLoader) {
+		GC_ClassLoaderSegmentIterator segmentIterator(classLoader, MEMORY_TYPE_RAM_CLASS);
+		while (NULL != (segment = segmentIterator.nextSegment())) {
+			if (_singleThread || J9MODRON_HANDLE_NEXT_WORK_UNIT(env)) {
 				GC_ClassHeapIterator classHeapIterator(static_cast<J9JavaVM*>(_omrVM->_language_vm), segment);
-				while(NULL != (clazz = classHeapIterator.nextClass())) {
+				while (NULL != (clazz = classHeapIterator.nextClass())) {
 					doClass(clazz);
 					if (shouldYieldFromClassScan(100000)) {
 						yield();
 					}
 				}
 			}
 		}
-	}
 
-	/* Do applicationClassLoader */
-	if (NULL != static_cast<J9JavaVM*>(_omrVM->_language_vm)->applicationClassLoader) {
-		GC_ClassLoaderSegmentIterator segmentIterator(static_cast<J9JavaVM*>(_omrVM->_language_vm)->applicationClassLoader, MEMORY_TYPE_RAM_CLASS);
-		while(NULL != (segment = segmentIterator.nextSegment())) {
-			if(_singleThread || J9MODRON_HANDLE_NEXT_WORK_UNIT(env)) {
-				GC_ClassHeapIterator classHeapIterator(static_cast<J9JavaVM*>(_omrVM->_language_vm), segment);
-				while(NULL != (clazz = classHeapIterator.nextClass())) {
-					doClass(clazz);
-					if (shouldYieldFromClassScan(100000)) {
-						yield();
-					}
-				}
-			}
+		if (_singleThread || J9MODRON_HANDLE_NEXT_WORK_UNIT(env)) {
+			scanModularityObjects(classLoader);
 		}
 	}
-
-	condYield();
-
-	reportScanningEnded(RootScannerEntity_PermanentClasses);
 }
 #endif /* J9VM_GC_DYNAMIC_CLASS_UNLOADING */
 

runtime/gc_base/RootScanner.hpp

@@ -122,6 +122,14 @@ class MM_RootScanner : public MM_BaseVirtual
 	void scanArrayObject(MM_EnvironmentBase *env, J9Object *objectPtr, MM_MemoryPool *memoryPool, MM_HeapRegionManager *manager, uintptr_t memoryType);
 
 	bool isContinuationListEmpty(MM_EnvironmentBase *env);
+
+	/**
+	 * Scan all objects from class loader.
+	 * @param env thread GC environment
+	 * @param classLoader class loader address
+	 */
+	void scanClassloader(MM_EnvironmentBase *env, J9ClassLoader *classLoader);
+
 protected:
 	/* Family of yielding methods to be overridden by incremental scanners such
 	 * as the RealtimeRootScanner. The default implementations of these do