Examples with GCSegmentIterator com.ibm.j9ddr.vm29.j9.gc.GCSegmentIterator used on opensource projects

Example 1 with GCSegmentIterator

use of com.ibm.j9ddr.vm29.j9.gc.GCSegmentIterator in project openj9 by eclipse.

the class RootScanner method scanPermanentClasses.

protected void scanPermanentClasses() throws CorruptDataException {
    J9ClassLoaderPointer sysClassLoader = _vm.systemClassLoader();
    J9ClassLoaderPointer appClassLoader = J9ClassLoaderPointer.cast(_vm.applicationClassLoader());
    GCSegmentIterator segmentIterator = GCSegmentIterator.fromJ9MemorySegmentList(_vm.classMemorySegments(), J9MemorySegment.MEMORY_TYPE_RAM_CLASS);
    setReachability(Reachability.STRONG);
    while (segmentIterator.hasNext()) {
        J9MemorySegmentPointer segment = segmentIterator.next();
        if (segment.classLoader().equals(sysClassLoader) || segment.classLoader().equals(appClassLoader)) {
            GCClassHeapIterator classHeapIterator = GCClassHeapIterator.fromJ9MemorySegment(segment);
            while (classHeapIterator.hasNext()) {
                doClass(classHeapIterator.next());
            }
        }
    }
}

Example 2 with GCSegmentIterator

use of com.ibm.j9ddr.vm29.j9.gc.GCSegmentIterator in project openj9 by eclipse.

the class VmCheckCommand method checkJ9ClassSanity.

/*
	 *  Based on vmchk/checkclasses.c r1.7
	 *
	 *	J9Class sanity:
	 *		Eyecatcher check:
	 *			Ensure J9Class->eyecatcher == 0x99669966.
	 *
	 *		Superclasses check:
	 *			Ensure J9Class->superclasses != null unless J9Class is Object.
	 *
	 *		ClassObject null check:
	 *			Ensure J9Class->classObject != null if (J9Class->initializeStatus == J9ClassInitSucceeded)
	 *
	 *		ClassLoader segment check:
	 *			Ensure J9Class->classLoader->classSegments contains J9Class.
	 *
	 *		ConstantPool check:
	 *			Ensure J9Class->ramConstantPool->ramClass is equal to the J9Class.
	 *
	 *		Subclass hierarchy check:
	 *			Ensure subclasses can be traversed per the J9Class classDepth.
	 *
	 *		Obsolete class check:
	 *			Ensure obsolete classes are found in the replacedClass linked list on the currentClass.
	 */
private void checkJ9ClassSanity(J9JavaVMPointer javaVM, PrintStream out) throws CorruptDataException {
    reportMessage(out, "Checking classes");
    // Stolen from RootScaner.scanClasses()
    // GCClassLoaderIterator gcClassLoaderIterator =
    // GCClassLoaderIterator.from();
    GCSegmentIterator segmentIterator = GCSegmentIterator.fromJ9MemorySegmentList(javaVM.classMemorySegments(), J9MemorySegment.MEMORY_TYPE_RAM_CLASS);
    int count = 0;
    int obsoleteCount = 0;
    while (segmentIterator.hasNext()) {
        J9MemorySegmentPointer segment = segmentIterator.next();
        GCClassHeapIterator classHeapIterator = GCClassHeapIterator.fromJ9MemorySegment(segment);
        while (classHeapIterator.hasNext()) {
            J9ClassPointer clazz = classHeapIterator.next();
            if (!J9ClassHelper.isObsolete(clazz)) {
                verifyJ9Class(javaVM, out, clazz);
            } else {
                verifyObsoleteJ9Class(javaVM, out, clazz);
                obsoleteCount++;
            }
            count++;
        }
    }
    reportMessage(out, "Checking %d classes (%d obsolete) done", count, obsoleteCount);
}

Example 3 with GCSegmentIterator

use of com.ibm.j9ddr.vm29.j9.gc.GCSegmentIterator in project openj9 by eclipse.

the class VmCheckCommand method checkJ9MethodSanity.

/*
	 *  Based on vmchk/checkmethods.c r1.5
	 * 
	 *	J9Method sanity:
	 *		Bytecode check:
	 *			Ensure (bytecodes - sizeof(J9ROMMethod) is in the right "area" to be a ROM Method.
	 *			Use ROMClass to determine where ROM methods for that class begin.
	 *		Constant pool check:
	 *			Ensure method's constant pool is the same as that of its J9Class.
	 *			Useful to validate that HCR doesn't violate this invariant.
	 *		VTable check:
	 *			If method of a non-interface class has modifier J9AccMethodVTable,
	 *			ensure it exists in the VTable of its J9Class.
	 *			Useful to validate that HCR doesn't violate this invariant.
	 */
private void checkJ9MethodSanity(J9JavaVMPointer vm, PrintStream out) throws CorruptDataException {
    reportMessage(out, "Checking methods");
    // Stolen from RootScaner.scanClasses()
    // GCClassLoaderIterator gcClassLoaderIterator =
    // GCClassLoaderIterator.from();
    GCSegmentIterator segmentIterator = GCSegmentIterator.fromJ9MemorySegmentList(vm.classMemorySegments(), J9MemorySegment.MEMORY_TYPE_RAM_CLASS);
    int count = 0;
    while (segmentIterator.hasNext()) {
        J9MemorySegmentPointer segment = segmentIterator.next();
        GCClassHeapIterator classHeapIterator = GCClassHeapIterator.fromJ9MemorySegment(segment);
        while (classHeapIterator.hasNext()) {
            J9ClassPointer clazz = classHeapIterator.next();
            if (!J9ClassHelper.isObsolete(clazz)) {
                count += verifyClassMethods(vm, out, clazz);
            }
        }
    }
    reportMessage(out, "Checking %d methods done", count);
}

Example 4 with GCSegmentIterator

use of com.ibm.j9ddr.vm29.j9.gc.GCSegmentIterator in project openj9 by eclipse.

the class CheckClassHeap method check.

@Override
public void check() {
    try {
        GCSegmentIterator segmentIterator = GCSegmentIterator.fromJ9MemorySegmentList(_javaVM.classMemorySegments(), J9MemorySegment.MEMORY_TYPE_RAM_CLASS);
        while (segmentIterator.hasNext()) {
            J9MemorySegmentPointer segment = segmentIterator.next();
            _engine.clearPreviousObjects();
            GCClassHeapIterator classHeapIterator = GCClassHeapIterator.fromJ9MemorySegment(segment);
            while (classHeapIterator.hasNext()) {
                J9ClassPointer clazz = classHeapIterator.next();
                if (_engine.checkClassHeap(clazz, segment) != CheckBase.J9MODRON_SLOT_ITERATOR_OK) {
                    return;
                }
                _engine.pushPreviousClass(clazz);
            }
        }
    } catch (CorruptDataException e) {
    // TODO: handle exception
    }
}

Example 5 with GCSegmentIterator

use of com.ibm.j9ddr.vm29.j9.gc.GCSegmentIterator in project openj9 by eclipse.

the class RootScanner method scanClasses.

protected void scanClasses() throws CorruptDataException {
    J9ClassLoaderPointer sysClassLoader = _vm.systemClassLoader();
    J9ClassLoaderPointer appClassLoader = J9ClassLoaderPointer.cast(_vm.applicationClassLoader());
    GCSegmentIterator segmentIterator = GCSegmentIterator.fromJ9MemorySegmentList(_vm.classMemorySegments(), J9MemorySegment.MEMORY_TYPE_RAM_CLASS);
    while (segmentIterator.hasNext()) {
        J9MemorySegmentPointer segment = segmentIterator.next();
        GCClassHeapIterator classHeapIterator = GCClassHeapIterator.fromJ9MemorySegment(segment);
        while (classHeapIterator.hasNext()) {
            J9ClassPointer clazz = classHeapIterator.next();
            Reachability reachability;
            if (J9BuildFlags.gc_dynamicClassUnloading) {
                long dynamicClassUnloadingFlag = _extensions.dynamicClassUnloading();
                if (MM_GCExtensions$DynamicClassUnloading.DYNAMIC_CLASS_UNLOADING_NEVER == dynamicClassUnloadingFlag) {
                    reachability = Reachability.STRONG;
                } else {
                    if (clazz.classLoader().eq(sysClassLoader) || clazz.classLoader().eq(appClassLoader)) {
                        reachability = Reachability.STRONG;
                    } else {
                        reachability = Reachability.WEAK;
                    }
                }
            } else {
                reachability = Reachability.STRONG;
            }
            setReachability(reachability);
            doClass(clazz);
        }
    }
}