Add Disable Global Continuation Lists option

runtime/gc_base/GCExtensions.cpp

@@ -28,6 +28,7 @@
 #include "j9memcategories.h"
 #include "j9nongenerated.h"
 #include "j9port.h"
+#include "ModronAssertions.h"
 #include "util_api.h"
 
 #include "EnvironmentBase.hpp"
@@ -295,3 +296,18 @@ MM_GCExtensions::registerScavenger(MM_Scavenger *scavenger)
 	Assert_MM_true(isScavengerEnabled());
 	((MM_StandardAccessBarrier *)accessBarrier)->registerScavenger(scavenger);
 }
+
+void
+MM_GCExtensions::releaseNativesForContinuationObject(MM_EnvironmentBase* env, j9object_t objectPtr)
+{
+#if JAVA_SPEC_VERSION >= 19
+	J9VMThread *vmThread = (J9VMThread *)env->getLanguageVMThread();
+
+	if (verify_continuation_list == continuationListOption) {
+		J9VMContinuation *continuation = J9VMJDKINTERNALVMCONTINUATION_VMREF(vmThread, objectPtr);
+		Assert_MM_true(NULL == continuation);
+	} else {
+		getJavaVM()->internalVMFunctions->freeContinuation(vmThread, objectPtr);
+	}
+#endif /* JAVA_SPEC_VERSION >= 19 */
+}

runtime/gc_base/GCExtensions.hpp

@@ -197,6 +197,13 @@ class MM_GCExtensions : public MM_GCExtensionsBase {
 	UDATA freeSizeThresholdForSurvivor; /**< if average freeSize(freeSize/freeCount) of the region is smaller than the Threshold, the region would not be reused by collector as survivor, for balanced GC only */
 	bool recycleRemainders; /**< true if need to recycle TLHRemainders at the end of PGC, for balanced GC only */
 
+	enum ContinuationListOption {
+		disable_continuation_list = 0,
+		enable_continuation_list = 1,
+		verify_continuation_list = 2,
+	};
+	ContinuationListOption continuationListOption;
+
 protected:
 private:
 protected:
@@ -290,6 +297,8 @@ class MM_GCExtensions : public MM_GCExtensionsBase {
 	MMINLINE MM_ContinuationObjectList* getContinuationObjectLists() { return continuationObjectLists; }
 	MMINLINE void setContinuationObjectLists(MM_ContinuationObjectList* newContinuationObjectLists) { continuationObjectLists = newContinuationObjectLists; }
 
+	void releaseNativesForContinuationObject(MM_EnvironmentBase* env, j9object_t objectPtr);
+
 	/**
 	 * Create a GCExtensions object
 	 */
@@ -337,6 +346,7 @@ class MM_GCExtensions : public MM_GCExtensionsBase {
 		, minimumFreeSizeForSurvivor(DEFAULT_SURVIVOR_MINIMUM_FREESIZE)
 		, freeSizeThresholdForSurvivor(DEFAULT_SURVIVOR_THRESHOLD)
 		, recycleRemainders(true)
+		, continuationListOption(verify_continuation_list)
 	{
 		_typeId = __FUNCTION__;
 	}

runtime/gc_base/modronapi.cpp

@@ -1036,10 +1036,14 @@ continuationObjectCreated(J9VMThread *vmThread, j9object_t object)
 	Assert_MM_true(NULL != object);
 	MM_EnvironmentBase *env = MM_EnvironmentBase::getEnvironment(vmThread->omrVMThread);
 
-	env->getGCEnvironment()->_continuationObjectBuffer->add(env, object);
-	MM_ObjectAllocationInterface *objectAllocation = env->_objectAllocationInterface;
-	if (NULL != objectAllocation) {
-		objectAllocation->getAllocationStats()->_continuationObjectCount += 1;
+	if (MM_GCExtensions::disable_continuation_list != MM_GCExtensions::getExtensions(env)->continuationListOption) {
+
+		env->getGCEnvironment()->_continuationObjectBuffer->add(env, object);
+		MM_ObjectAllocationInterface *objectAllocation = env->_objectAllocationInterface;
+
+		if (NULL != objectAllocation) {
+			objectAllocation->getAllocationStats()->_continuationObjectCount += 1;
+		}
 	}
 	return 0;
 }

runtime/gc_glue_java/MarkingSchemeRootClearer.cpp

@@ -331,7 +331,7 @@ MM_MarkingSchemeRootClearer::scanContinuationObjects(MM_EnvironmentBase *env)
 							} else {
 								/* object was not previously marked */
 								gcEnv->_markJavaStats._continuationCleared += 1;
-								VM_VMHelpers::cleanupContinuationObject((J9VMThread *)env->getLanguageVMThread(), object);
+								_extensions->releaseNativesForContinuationObject(env, object);
 							}
 							object = next;
 						}

runtime/gc_glue_java/MetronomeDelegate.cpp

@@ -1342,7 +1342,7 @@ MM_MetronomeDelegate::scanContinuationObjects(MM_EnvironmentRealtime *env)
 						buffer->add(env, object);
 					} else {
 						gcEnv->_markJavaStats._continuationCleared += 1;
-						VM_VMHelpers::cleanupContinuationObject((J9VMThread *)env->getLanguageVMThread(), object);
+						_extensions->releaseNativesForContinuationObject(env, object);
 					}
 					object = next;
 

runtime/gc_glue_java/ScavengerRootClearer.cpp

@@ -241,7 +241,7 @@ MM_ScavengerRootClearer::scavengeContinuationObjects(MM_EnvironmentStandard *env
 							if (!forwardedHeader.isForwardedPointer()) {
 								Assert_GC_true_with_message2(env, _scavenger->isObjectInEvacuateMemory(object), "Continuation object  %p should be a dead object, forwardedHeader=%p\n", object, &forwardedHeader);
 								gcEnv->_scavengerJavaStats._continuationCleared += 1;
-								VM_VMHelpers::cleanupContinuationObject((J9VMThread *)env->getLanguageVMThread(), object);
+								_extensions->releaseNativesForContinuationObject(env, object);
 							} else {
 								omrobjectptr_t forwardedPtr = forwardedHeader.getForwardedObject();
 								Assert_GC_true_with_message(env, NULL != forwardedPtr, "Continuation object  %p should be forwarded\n", object);

runtime/gc_modron_startup/mmparseXXgc.cpp

@@ -1515,6 +1515,20 @@ gcParseXXgcArguments(J9JavaVM *vm, char *optArg)
 			continue;
 		}
 
+		if (try_scan(&scan_start, "disableContinuationList")) {
+			extensions->continuationListOption = MM_GCExtensions::disable_continuation_list;
+			continue;
+		}
+
+		if (try_scan(&scan_start, "enableContinuationList")) {
+			extensions->continuationListOption = MM_GCExtensions::enable_continuation_list;
+			continue;
+		}
+
+		if (try_scan(&scan_start, "verifyContinuationList")) {
+			extensions->continuationListOption = MM_GCExtensions::verify_continuation_list;
+			continue;
+		}
 
 		/* Couldn't find a match for arguments */
 		j9nls_printf(PORTLIB, J9NLS_ERROR, J9NLS_GC_OPTION_UNKNOWN, error_scan);

runtime/gc_vlhgc/CopyForwardScheme.cpp

@@ -3549,7 +3549,7 @@ MM_CopyForwardScheme::scanContinuationObjects(MM_EnvironmentVLHGC *env)
 					if (NULL == forwardedPtr) {
 						/* object was not previously marked, clean up */
 						env->_copyForwardStats._continuationCleared += 1;
-						VM_VMHelpers::cleanupContinuationObject((J9VMThread *)env->getLanguageVMThread(), pointer);
+						_extensions->releaseNativesForContinuationObject(env, pointer);
 					} else {
 						env->getGCEnvironment()->_continuationObjectBuffer->add(env, forwardedPtr);
 					}

runtime/gc_vlhgc/GlobalMarkingScheme.cpp

@@ -1111,8 +1111,8 @@ MM_GlobalMarkingScheme::scanContinuationObjects(MM_EnvironmentVLHGC *env)
 						if (isMarked(object)) {
 							env->getGCEnvironment()->_continuationObjectBuffer->add(env, object);
 						} else {
-							VM_VMHelpers::cleanupContinuationObject((J9VMThread *)env->getLanguageVMThread(), object);
 							env->_markVLHGCStats._continuationCleared += 1;
+							_extensions->releaseNativesForContinuationObject(env, object);
 						}
 						object = next;
 					}

runtime/oti/VMHelpers.hpp

@@ -2157,14 +2157,6 @@ class VM_VMHelpers
 		return needScan;
 	}
 
-	static VMINLINE void
-	cleanupContinuationObject(J9VMThread *vmThread, J9Object *objectPtr)
-	{
-#if JAVA_SPEC_VERSION >= 19
-		vmThread->javaVM->internalVMFunctions->freeContinuation(vmThread, objectPtr);
-#endif /* JAVA_SPEC_VERSION >= 19 */
-	}
-
 	static VMINLINE UDATA
 	setVMState(J9VMThread *currentThread, UDATA newState)
 	{