8003424: Enable Class Data Sharing for CompressedOops
8016729: ObjectAlignmentInBytes=16 now forces the use of heap based compressed oops
8005933: The -Xshare:auto option is ignored for -server
Summary: Move klass metaspace above the heap and support CDS with compressed klass ptrs.
Reviewed-by: coleenp, kvn, mgerdin, tschatzl, stefank
/*
* Copyright (c) 1997, 2013, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*
*/
#include "precompiled.hpp"
#include "classfile/classLoader.hpp"
#include "classfile/classLoaderData.hpp"
#include "classfile/javaClasses.hpp"
#include "classfile/symbolTable.hpp"
#include "classfile/systemDictionary.hpp"
#include "classfile/vmSymbols.hpp"
#include "code/codeCache.hpp"
#include "code/dependencies.hpp"
#include "gc_interface/collectedHeap.inline.hpp"
#include "interpreter/interpreter.hpp"
#include "memory/cardTableModRefBS.hpp"
#include "memory/gcLocker.inline.hpp"
#include "memory/genCollectedHeap.hpp"
#include "memory/genRemSet.hpp"
#include "memory/generation.hpp"
#include "memory/metadataFactory.hpp"
#include "memory/metaspaceShared.hpp"
#include "memory/oopFactory.hpp"
#include "memory/space.hpp"
#include "memory/universe.hpp"
#include "memory/universe.inline.hpp"
#include "oops/constantPool.hpp"
#include "oops/instanceClassLoaderKlass.hpp"
#include "oops/instanceKlass.hpp"
#include "oops/instanceMirrorKlass.hpp"
#include "oops/instanceRefKlass.hpp"
#include "oops/oop.inline.hpp"
#include "oops/typeArrayKlass.hpp"
#include "prims/jvmtiRedefineClassesTrace.hpp"
#include "runtime/arguments.hpp"
#include "runtime/deoptimization.hpp"
#include "runtime/fprofiler.hpp"
#include "runtime/handles.inline.hpp"
#include "runtime/init.hpp"
#include "runtime/java.hpp"
#include "runtime/javaCalls.hpp"
#include "runtime/sharedRuntime.hpp"
#include "runtime/synchronizer.hpp"
#include "runtime/thread.inline.hpp"
#include "runtime/timer.hpp"
#include "runtime/vm_operations.hpp"
#include "services/memoryService.hpp"
#include "utilities/copy.hpp"
#include "utilities/events.hpp"
#include "utilities/hashtable.inline.hpp"
#include "utilities/preserveException.hpp"
#include "utilities/macros.hpp"
#if INCLUDE_ALL_GCS
#include "gc_implementation/concurrentMarkSweep/cmsAdaptiveSizePolicy.hpp"
#include "gc_implementation/concurrentMarkSweep/cmsCollectorPolicy.hpp"
#include "gc_implementation/g1/g1CollectedHeap.inline.hpp"
#include "gc_implementation/g1/g1CollectorPolicy.hpp"
#include "gc_implementation/parallelScavenge/parallelScavengeHeap.hpp"
#endif // INCLUDE_ALL_GCS
// Known objects
Klass* Universe::_boolArrayKlassObj = NULL;
Klass* Universe::_byteArrayKlassObj = NULL;
Klass* Universe::_charArrayKlassObj = NULL;
Klass* Universe::_intArrayKlassObj = NULL;
Klass* Universe::_shortArrayKlassObj = NULL;
Klass* Universe::_longArrayKlassObj = NULL;
Klass* Universe::_singleArrayKlassObj = NULL;
Klass* Universe::_doubleArrayKlassObj = NULL;
Klass* Universe::_typeArrayKlassObjs[T_VOID+1] = { NULL /*, NULL...*/ };
Klass* Universe::_objectArrayKlassObj = NULL;
oop Universe::_int_mirror = NULL;
oop Universe::_float_mirror = NULL;
oop Universe::_double_mirror = NULL;
oop Universe::_byte_mirror = NULL;
oop Universe::_bool_mirror = NULL;
oop Universe::_char_mirror = NULL;
oop Universe::_long_mirror = NULL;
oop Universe::_short_mirror = NULL;
oop Universe::_void_mirror = NULL;
oop Universe::_mirrors[T_VOID+1] = { NULL /*, NULL...*/ };
oop Universe::_main_thread_group = NULL;
oop Universe::_system_thread_group = NULL;
objArrayOop Universe::_the_empty_class_klass_array = NULL;
Array<Klass*>* Universe::_the_array_interfaces_array = NULL;
oop Universe::_the_null_string = NULL;
oop Universe::_the_min_jint_string = NULL;
LatestMethodCache* Universe::_finalizer_register_cache = NULL;
LatestMethodCache* Universe::_loader_addClass_cache = NULL;
LatestMethodCache* Universe::_pd_implies_cache = NULL;
oop Universe::_out_of_memory_error_java_heap = NULL;
oop Universe::_out_of_memory_error_metaspace = NULL;
oop Universe::_out_of_memory_error_class_metaspace = NULL;
oop Universe::_out_of_memory_error_array_size = NULL;
oop Universe::_out_of_memory_error_gc_overhead_limit = NULL;
objArrayOop Universe::_preallocated_out_of_memory_error_array = NULL;
volatile jint Universe::_preallocated_out_of_memory_error_avail_count = 0;
bool Universe::_verify_in_progress = false;
oop Universe::_null_ptr_exception_instance = NULL;
oop Universe::_arithmetic_exception_instance = NULL;
oop Universe::_virtual_machine_error_instance = NULL;
oop Universe::_vm_exception = NULL;
Array<int>* Universe::_the_empty_int_array = NULL;
Array<u2>* Universe::_the_empty_short_array = NULL;
Array<Klass*>* Universe::_the_empty_klass_array = NULL;
Array<Method*>* Universe::_the_empty_method_array = NULL;
// These variables are guarded by FullGCALot_lock.
debug_only(objArrayOop Universe::_fullgc_alot_dummy_array = NULL;)
debug_only(int Universe::_fullgc_alot_dummy_next = 0;)
// Heap
int Universe::_verify_count = 0;
int Universe::_base_vtable_size = 0;
bool Universe::_bootstrapping = false;
bool Universe::_fully_initialized = false;
size_t Universe::_heap_capacity_at_last_gc;
size_t Universe::_heap_used_at_last_gc = 0;
CollectedHeap* Universe::_collectedHeap = NULL;
NarrowPtrStruct Universe::_narrow_oop = { NULL, 0, true };
NarrowPtrStruct Universe::_narrow_klass = { NULL, 0, true };
address Universe::_narrow_ptrs_base;
void Universe::basic_type_classes_do(void f(Klass*)) {
f(boolArrayKlassObj());
f(byteArrayKlassObj());
f(charArrayKlassObj());
f(intArrayKlassObj());
f(shortArrayKlassObj());
f(longArrayKlassObj());
f(singleArrayKlassObj());
f(doubleArrayKlassObj());
}
void Universe::oops_do(OopClosure* f, bool do_all) {
f->do_oop((oop*) &_int_mirror);
f->do_oop((oop*) &_float_mirror);
f->do_oop((oop*) &_double_mirror);
f->do_oop((oop*) &_byte_mirror);
f->do_oop((oop*) &_bool_mirror);
f->do_oop((oop*) &_char_mirror);
f->do_oop((oop*) &_long_mirror);
f->do_oop((oop*) &_short_mirror);
f->do_oop((oop*) &_void_mirror);
for (int i = T_BOOLEAN; i < T_VOID+1; i++) {
f->do_oop((oop*) &_mirrors[i]);
}
assert(_mirrors[0] == NULL && _mirrors[T_BOOLEAN - 1] == NULL, "checking");
f->do_oop((oop*)&_the_empty_class_klass_array);
f->do_oop((oop*)&_the_null_string);
f->do_oop((oop*)&_the_min_jint_string);
f->do_oop((oop*)&_out_of_memory_error_java_heap);
f->do_oop((oop*)&_out_of_memory_error_metaspace);
f->do_oop((oop*)&_out_of_memory_error_class_metaspace);
f->do_oop((oop*)&_out_of_memory_error_array_size);
f->do_oop((oop*)&_out_of_memory_error_gc_overhead_limit);
f->do_oop((oop*)&_preallocated_out_of_memory_error_array);
f->do_oop((oop*)&_null_ptr_exception_instance);
f->do_oop((oop*)&_arithmetic_exception_instance);
f->do_oop((oop*)&_virtual_machine_error_instance);
f->do_oop((oop*)&_main_thread_group);
f->do_oop((oop*)&_system_thread_group);
f->do_oop((oop*)&_vm_exception);
debug_only(f->do_oop((oop*)&_fullgc_alot_dummy_array);)
}
// Serialize metadata in and out of CDS archive, not oops.
void Universe::serialize(SerializeClosure* f, bool do_all) {
f->do_ptr((void**)&_boolArrayKlassObj);
f->do_ptr((void**)&_byteArrayKlassObj);
f->do_ptr((void**)&_charArrayKlassObj);
f->do_ptr((void**)&_intArrayKlassObj);
f->do_ptr((void**)&_shortArrayKlassObj);
f->do_ptr((void**)&_longArrayKlassObj);
f->do_ptr((void**)&_singleArrayKlassObj);
f->do_ptr((void**)&_doubleArrayKlassObj);
f->do_ptr((void**)&_objectArrayKlassObj);
{
for (int i = 0; i < T_VOID+1; i++) {
if (_typeArrayKlassObjs[i] != NULL) {
assert(i >= T_BOOLEAN, "checking");
f->do_ptr((void**)&_typeArrayKlassObjs[i]);
} else if (do_all) {
f->do_ptr((void**)&_typeArrayKlassObjs[i]);
}
}
}
f->do_ptr((void**)&_the_array_interfaces_array);
f->do_ptr((void**)&_the_empty_int_array);
f->do_ptr((void**)&_the_empty_short_array);
f->do_ptr((void**)&_the_empty_method_array);
f->do_ptr((void**)&_the_empty_klass_array);
_finalizer_register_cache->serialize(f);
_loader_addClass_cache->serialize(f);
_pd_implies_cache->serialize(f);
}
void Universe::check_alignment(uintx size, uintx alignment, const char* name) {
if (size < alignment || size % alignment != 0) {
vm_exit_during_initialization(
err_msg("Size of %s (" UINTX_FORMAT " bytes) must be aligned to " UINTX_FORMAT " bytes", name, size, alignment));
}
}
void initialize_basic_type_klass(Klass* k, TRAPS) {
Klass* ok = SystemDictionary::Object_klass();
if (UseSharedSpaces) {
assert(k->super() == ok, "u3");
k->restore_unshareable_info(CHECK);
} else {
k->initialize_supers(ok, CHECK);
}
k->append_to_sibling_list();
}
void Universe::genesis(TRAPS) {
ResourceMark rm;
{ FlagSetting fs(_bootstrapping, true);
{ MutexLocker mc(Compile_lock);
// determine base vtable size; without that we cannot create the array klasses
compute_base_vtable_size();
if (!UseSharedSpaces) {
_boolArrayKlassObj = TypeArrayKlass::create_klass(T_BOOLEAN, sizeof(jboolean), CHECK);
_charArrayKlassObj = TypeArrayKlass::create_klass(T_CHAR, sizeof(jchar), CHECK);
_singleArrayKlassObj = TypeArrayKlass::create_klass(T_FLOAT, sizeof(jfloat), CHECK);
_doubleArrayKlassObj = TypeArrayKlass::create_klass(T_DOUBLE, sizeof(jdouble), CHECK);
_byteArrayKlassObj = TypeArrayKlass::create_klass(T_BYTE, sizeof(jbyte), CHECK);
_shortArrayKlassObj = TypeArrayKlass::create_klass(T_SHORT, sizeof(jshort), CHECK);
_intArrayKlassObj = TypeArrayKlass::create_klass(T_INT, sizeof(jint), CHECK);
_longArrayKlassObj = TypeArrayKlass::create_klass(T_LONG, sizeof(jlong), CHECK);
_typeArrayKlassObjs[T_BOOLEAN] = _boolArrayKlassObj;
_typeArrayKlassObjs[T_CHAR] = _charArrayKlassObj;
_typeArrayKlassObjs[T_FLOAT] = _singleArrayKlassObj;
_typeArrayKlassObjs[T_DOUBLE] = _doubleArrayKlassObj;
_typeArrayKlassObjs[T_BYTE] = _byteArrayKlassObj;
_typeArrayKlassObjs[T_SHORT] = _shortArrayKlassObj;
_typeArrayKlassObjs[T_INT] = _intArrayKlassObj;
_typeArrayKlassObjs[T_LONG] = _longArrayKlassObj;
ClassLoaderData* null_cld = ClassLoaderData::the_null_class_loader_data();
_the_array_interfaces_array = MetadataFactory::new_array<Klass*>(null_cld, 2, NULL, CHECK);
_the_empty_int_array = MetadataFactory::new_array<int>(null_cld, 0, CHECK);
_the_empty_short_array = MetadataFactory::new_array<u2>(null_cld, 0, CHECK);
_the_empty_method_array = MetadataFactory::new_array<Method*>(null_cld, 0, CHECK);
_the_empty_klass_array = MetadataFactory::new_array<Klass*>(null_cld, 0, CHECK);
}
}
vmSymbols::initialize(CHECK);
SystemDictionary::initialize(CHECK);
Klass* ok = SystemDictionary::Object_klass();
_the_null_string = StringTable::intern("null", CHECK);
_the_min_jint_string = StringTable::intern("-2147483648", CHECK);
if (UseSharedSpaces) {
// Verify shared interfaces array.
assert(_the_array_interfaces_array->at(0) ==
SystemDictionary::Cloneable_klass(), "u3");
assert(_the_array_interfaces_array->at(1) ==
SystemDictionary::Serializable_klass(), "u3");
} else {
// Set up shared interfaces array. (Do this before supers are set up.)
_the_array_interfaces_array->at_put(0, SystemDictionary::Cloneable_klass());
_the_array_interfaces_array->at_put(1, SystemDictionary::Serializable_klass());
}
initialize_basic_type_klass(boolArrayKlassObj(), CHECK);
initialize_basic_type_klass(charArrayKlassObj(), CHECK);
initialize_basic_type_klass(singleArrayKlassObj(), CHECK);
initialize_basic_type_klass(doubleArrayKlassObj(), CHECK);
initialize_basic_type_klass(byteArrayKlassObj(), CHECK);
initialize_basic_type_klass(shortArrayKlassObj(), CHECK);
initialize_basic_type_klass(intArrayKlassObj(), CHECK);
initialize_basic_type_klass(longArrayKlassObj(), CHECK);
} // end of core bootstrapping
// Maybe this could be lifted up now that object array can be initialized
// during the bootstrapping.
// OLD
// Initialize _objectArrayKlass after core bootstraping to make
// sure the super class is set up properly for _objectArrayKlass.
// ---
// NEW
// Since some of the old system object arrays have been converted to
// ordinary object arrays, _objectArrayKlass will be loaded when
// SystemDictionary::initialize(CHECK); is run. See the extra check
// for Object_klass_loaded in objArrayKlassKlass::allocate_objArray_klass_impl.
_objectArrayKlassObj = InstanceKlass::
cast(SystemDictionary::Object_klass())->array_klass(1, CHECK);
// OLD
// Add the class to the class hierarchy manually to make sure that
// its vtable is initialized after core bootstrapping is completed.
// ---
// New
// Have already been initialized.
_objectArrayKlassObj->append_to_sibling_list();
// Compute is_jdk version flags.
// Only 1.3 or later has the java.lang.Shutdown class.
// Only 1.4 or later has the java.lang.CharSequence interface.
// Only 1.5 or later has the java.lang.management.MemoryUsage class.
if (JDK_Version::is_partially_initialized()) {
uint8_t jdk_version;
Klass* k = SystemDictionary::resolve_or_null(
vmSymbols::java_lang_management_MemoryUsage(), THREAD);
CLEAR_PENDING_EXCEPTION; // ignore exceptions
if (k == NULL) {
k = SystemDictionary::resolve_or_null(
vmSymbols::java_lang_CharSequence(), THREAD);
CLEAR_PENDING_EXCEPTION; // ignore exceptions
if (k == NULL) {
k = SystemDictionary::resolve_or_null(
vmSymbols::java_lang_Shutdown(), THREAD);
CLEAR_PENDING_EXCEPTION; // ignore exceptions
if (k == NULL) {
jdk_version = 2;
} else {
jdk_version = 3;
}
} else {
jdk_version = 4;
}
} else {
jdk_version = 5;
}
JDK_Version::fully_initialize(jdk_version);
}
#ifdef ASSERT
if (FullGCALot) {
// Allocate an array of dummy objects.
// We'd like these to be at the bottom of the old generation,
// so that when we free one and then collect,
// (almost) the whole heap moves
// and we find out if we actually update all the oops correctly.
// But we can't allocate directly in the old generation,
// so we allocate wherever, and hope that the first collection
// moves these objects to the bottom of the old generation.
// We can allocate directly in the permanent generation, so we do.
int size;
if (UseConcMarkSweepGC) {
warning("Using +FullGCALot with concurrent mark sweep gc "
"will not force all objects to relocate");
size = FullGCALotDummies;
} else {
size = FullGCALotDummies * 2;
}
objArrayOop naked_array = oopFactory::new_objArray(SystemDictionary::Object_klass(), size, CHECK);
objArrayHandle dummy_array(THREAD, naked_array);
int i = 0;
while (i < size) {
// Allocate dummy in old generation
oop dummy = InstanceKlass::cast(SystemDictionary::Object_klass())->allocate_instance(CHECK);
dummy_array->obj_at_put(i++, dummy);
}
{
// Only modify the global variable inside the mutex.
// If we had a race to here, the other dummy_array instances
// and their elements just get dropped on the floor, which is fine.
MutexLocker ml(FullGCALot_lock);
if (_fullgc_alot_dummy_array == NULL) {
_fullgc_alot_dummy_array = dummy_array();
}
}
assert(i == _fullgc_alot_dummy_array->length(), "just checking");
}
#endif
// Initialize dependency array for null class loader
ClassLoaderData::the_null_class_loader_data()->init_dependencies(CHECK);
}
// CDS support for patching vtables in metadata in the shared archive.
// All types inherited from Metadata have vtables, but not types inherited
// from MetaspaceObj, because the latter does not have virtual functions.
// If the metadata type has a vtable, it cannot be shared in the read-only
// section of the CDS archive, because the vtable pointer is patched.
static inline void add_vtable(void** list, int* n, void* o, int count) {
guarantee((*n) < count, "vtable list too small");
void* vtable = dereference_vptr(o);
assert(*(void**)(vtable) != NULL, "invalid vtable");
list[(*n)++] = vtable;
}
void Universe::init_self_patching_vtbl_list(void** list, int count) {
int n = 0;
{ InstanceKlass o; add_vtable(list, &n, &o, count); }
{ InstanceClassLoaderKlass o; add_vtable(list, &n, &o, count); }
{ InstanceMirrorKlass o; add_vtable(list, &n, &o, count); }
{ InstanceRefKlass o; add_vtable(list, &n, &o, count); }
{ TypeArrayKlass o; add_vtable(list, &n, &o, count); }
{ ObjArrayKlass o; add_vtable(list, &n, &o, count); }
{ Method o; add_vtable(list, &n, &o, count); }
{ ConstantPool o; add_vtable(list, &n, &o, count); }
}
void Universe::initialize_basic_type_mirrors(TRAPS) {
assert(_int_mirror==NULL, "basic type mirrors already initialized");
_int_mirror =
java_lang_Class::create_basic_type_mirror("int", T_INT, CHECK);
_float_mirror =
java_lang_Class::create_basic_type_mirror("float", T_FLOAT, CHECK);
_double_mirror =
java_lang_Class::create_basic_type_mirror("double", T_DOUBLE, CHECK);
_byte_mirror =
java_lang_Class::create_basic_type_mirror("byte", T_BYTE, CHECK);
_bool_mirror =
java_lang_Class::create_basic_type_mirror("boolean",T_BOOLEAN, CHECK);
_char_mirror =
java_lang_Class::create_basic_type_mirror("char", T_CHAR, CHECK);
_long_mirror =
java_lang_Class::create_basic_type_mirror("long", T_LONG, CHECK);
_short_mirror =
java_lang_Class::create_basic_type_mirror("short", T_SHORT, CHECK);
_void_mirror =
java_lang_Class::create_basic_type_mirror("void", T_VOID, CHECK);
_mirrors[T_INT] = _int_mirror;
_mirrors[T_FLOAT] = _float_mirror;
_mirrors[T_DOUBLE] = _double_mirror;
_mirrors[T_BYTE] = _byte_mirror;
_mirrors[T_BOOLEAN] = _bool_mirror;
_mirrors[T_CHAR] = _char_mirror;
_mirrors[T_LONG] = _long_mirror;
_mirrors[T_SHORT] = _short_mirror;
_mirrors[T_VOID] = _void_mirror;
//_mirrors[T_OBJECT] = InstanceKlass::cast(_object_klass)->java_mirror();
//_mirrors[T_ARRAY] = InstanceKlass::cast(_object_klass)->java_mirror();
}
void Universe::fixup_mirrors(TRAPS) {
// Bootstrap problem: all classes gets a mirror (java.lang.Class instance) assigned eagerly,
// but we cannot do that for classes created before java.lang.Class is loaded. Here we simply
// walk over permanent objects created so far (mostly classes) and fixup their mirrors. Note
// that the number of objects allocated at this point is very small.
assert(SystemDictionary::Class_klass_loaded(), "java.lang.Class should be loaded");
HandleMark hm(THREAD);
// Cache the start of the static fields
InstanceMirrorKlass::init_offset_of_static_fields();
GrowableArray <Klass*>* list = java_lang_Class::fixup_mirror_list();
int list_length = list->length();
for (int i = 0; i < list_length; i++) {
Klass* k = list->at(i);
assert(k->is_klass(), "List should only hold classes");
EXCEPTION_MARK;
KlassHandle kh(THREAD, k);
java_lang_Class::fixup_mirror(kh, CATCH);
}
delete java_lang_Class::fixup_mirror_list();
java_lang_Class::set_fixup_mirror_list(NULL);
}
static bool has_run_finalizers_on_exit = false;
void Universe::run_finalizers_on_exit() {
if (has_run_finalizers_on_exit) return;
has_run_finalizers_on_exit = true;
// Called on VM exit. This ought to be run in a separate thread.
if (TraceReferenceGC) tty->print_cr("Callback to run finalizers on exit");
{
PRESERVE_EXCEPTION_MARK;
KlassHandle finalizer_klass(THREAD, SystemDictionary::Finalizer_klass());
JavaValue result(T_VOID);
JavaCalls::call_static(
&result,
finalizer_klass,
vmSymbols::run_finalizers_on_exit_name(),
vmSymbols::void_method_signature(),
THREAD
);
// Ignore any pending exceptions
CLEAR_PENDING_EXCEPTION;
}
}
// initialize_vtable could cause gc if
// 1) we specified true to initialize_vtable and
// 2) this ran after gc was enabled
// In case those ever change we use handles for oops
void Universe::reinitialize_vtable_of(KlassHandle k_h, TRAPS) {
// init vtable of k and all subclasses
Klass* ko = k_h();
klassVtable* vt = ko->vtable();
if (vt) vt->initialize_vtable(false, CHECK);
if (ko->oop_is_instance()) {
InstanceKlass* ik = (InstanceKlass*)ko;
for (KlassHandle s_h(THREAD, ik->subklass());
s_h() != NULL;
s_h = KlassHandle(THREAD, s_h()->next_sibling())) {
reinitialize_vtable_of(s_h, CHECK);
}
}
}
void initialize_itable_for_klass(Klass* k, TRAPS) {
InstanceKlass::cast(k)->itable()->initialize_itable(false, CHECK);
}
void Universe::reinitialize_itables(TRAPS) {
SystemDictionary::classes_do(initialize_itable_for_klass, CHECK);
}
bool Universe::on_page_boundary(void* addr) {
return ((uintptr_t) addr) % os::vm_page_size() == 0;
}
bool Universe::should_fill_in_stack_trace(Handle throwable) {
// never attempt to fill in the stack trace of preallocated errors that do not have
// backtrace. These errors are kept alive forever and may be "re-used" when all
// preallocated errors with backtrace have been consumed. Also need to avoid
// a potential loop which could happen if an out of memory occurs when attempting
// to allocate the backtrace.
return ((throwable() != Universe::_out_of_memory_error_java_heap) &&
(throwable() != Universe::_out_of_memory_error_metaspace) &&
(throwable() != Universe::_out_of_memory_error_class_metaspace) &&
(throwable() != Universe::_out_of_memory_error_array_size) &&
(throwable() != Universe::_out_of_memory_error_gc_overhead_limit));
}
oop Universe::gen_out_of_memory_error(oop default_err) {
// generate an out of memory error:
// - if there is a preallocated error with backtrace available then return it wth
// a filled in stack trace.
// - if there are no preallocated errors with backtrace available then return
// an error without backtrace.
int next;
if (_preallocated_out_of_memory_error_avail_count > 0) {
next = (int)Atomic::add(-1, &_preallocated_out_of_memory_error_avail_count);
assert(next < (int)PreallocatedOutOfMemoryErrorCount, "avail count is corrupt");
} else {
next = -1;
}
if (next < 0) {
// all preallocated errors have been used.
// return default
return default_err;
} else {
// get the error object at the slot and set set it to NULL so that the
// array isn't keeping it alive anymore.
oop exc = preallocated_out_of_memory_errors()->obj_at(next);
assert(exc != NULL, "slot has been used already");
preallocated_out_of_memory_errors()->obj_at_put(next, NULL);
// use the message from the default error
oop msg = java_lang_Throwable::message(default_err);
assert(msg != NULL, "no message");
java_lang_Throwable::set_message(exc, msg);
// populate the stack trace and return it.
java_lang_Throwable::fill_in_stack_trace_of_preallocated_backtrace(exc);
return exc;
}
}
static intptr_t non_oop_bits = 0;
void* Universe::non_oop_word() {
// Neither the high bits nor the low bits of this value is allowed
// to look like (respectively) the high or low bits of a real oop.
//
// High and low are CPU-specific notions, but low always includes
// the low-order bit. Since oops are always aligned at least mod 4,
// setting the low-order bit will ensure that the low half of the
// word will never look like that of a real oop.
//
// Using the OS-supplied non-memory-address word (usually 0 or -1)
// will take care of the high bits, however many there are.
if (non_oop_bits == 0) {
non_oop_bits = (intptr_t)os::non_memory_address_word() | 1;
}
return (void*)non_oop_bits;
}
jint universe_init() {
assert(!Universe::_fully_initialized, "called after initialize_vtables");
guarantee(1 << LogHeapWordSize == sizeof(HeapWord),
"LogHeapWordSize is incorrect.");
guarantee(sizeof(oop) >= sizeof(HeapWord), "HeapWord larger than oop?");
guarantee(sizeof(oop) % sizeof(HeapWord) == 0,
"oop size is not not a multiple of HeapWord size");
TraceTime timer("Genesis", TraceStartupTime);
GC_locker::lock(); // do not allow gc during bootstrapping
JavaClasses::compute_hard_coded_offsets();
jint status = Universe::initialize_heap();
if (status != JNI_OK) {
return status;
}
Metaspace::global_initialize();
// Create memory for metadata. Must be after initializing heap for
// DumpSharedSpaces.
ClassLoaderData::init_null_class_loader_data();
// We have a heap so create the Method* caches before
// Metaspace::initialize_shared_spaces() tries to populate them.
Universe::_finalizer_register_cache = new LatestMethodCache();
Universe::_loader_addClass_cache = new LatestMethodCache();
Universe::_pd_implies_cache = new LatestMethodCache();
if (UseSharedSpaces) {
// Read the data structures supporting the shared spaces (shared
// system dictionary, symbol table, etc.). After that, access to
// the file (other than the mapped regions) is no longer needed, and
// the file is closed. Closing the file does not affect the
// currently mapped regions.
MetaspaceShared::initialize_shared_spaces();
StringTable::create_table();
} else {
SymbolTable::create_table();
StringTable::create_table();
ClassLoader::create_package_info_table();
}
return JNI_OK;
}
// Choose the heap base address and oop encoding mode
// when compressed oops are used:
// Unscaled - Use 32-bits oops without encoding when
// NarrowOopHeapBaseMin + heap_size < 4Gb
// ZeroBased - Use zero based compressed oops with encoding when
// NarrowOopHeapBaseMin + heap_size < 32Gb
// HeapBased - Use compressed oops with heap base + encoding.
// 4Gb
static const uint64_t NarrowOopHeapMax = (uint64_t(max_juint) + 1);
// 32Gb
// OopEncodingHeapMax == NarrowOopHeapMax << LogMinObjAlignmentInBytes;
char* Universe::preferred_heap_base(size_t heap_size, NARROW_OOP_MODE mode) {
size_t base = 0;
#ifdef _LP64
if (UseCompressedOops) {
assert(mode == UnscaledNarrowOop ||
mode == ZeroBasedNarrowOop ||
mode == HeapBasedNarrowOop, "mode is invalid");
const size_t total_size = heap_size + HeapBaseMinAddress;
// Return specified base for the first request.
if (!FLAG_IS_DEFAULT(HeapBaseMinAddress) && (mode == UnscaledNarrowOop)) {
base = HeapBaseMinAddress;
// If the total size is small enough to allow UnscaledNarrowOop then
// just use UnscaledNarrowOop.
} else if ((total_size <= OopEncodingHeapMax) && (mode != HeapBasedNarrowOop)) {
if ((total_size <= NarrowOopHeapMax) && (mode == UnscaledNarrowOop) &&
(Universe::narrow_oop_shift() == 0)) {
// Use 32-bits oops without encoding and
// place heap's top on the 4Gb boundary
base = (NarrowOopHeapMax - heap_size);
} else {
// Can't reserve with NarrowOopShift == 0
Universe::set_narrow_oop_shift(LogMinObjAlignmentInBytes);
if (mode == UnscaledNarrowOop ||
mode == ZeroBasedNarrowOop && total_size <= NarrowOopHeapMax) {
// Use zero based compressed oops with encoding and
// place heap's top on the 32Gb boundary in case
// total_size > 4Gb or failed to reserve below 4Gb.
base = (OopEncodingHeapMax - heap_size);
}
}
} else {
// UnscaledNarrowOop encoding didn't work, and no base was found for ZeroBasedOops or
// HeapBasedNarrowOop encoding was requested. So, can't reserve below 32Gb.
Universe::set_narrow_oop_shift(LogMinObjAlignmentInBytes);
}
// Set narrow_oop_base and narrow_oop_use_implicit_null_checks
// used in ReservedHeapSpace() constructors.
// The final values will be set in initialize_heap() below.
if ((base != 0) && ((base + heap_size) <= OopEncodingHeapMax)) {
// Use zero based compressed oops
Universe::set_narrow_oop_base(NULL);
// Don't need guard page for implicit checks in indexed
// addressing mode with zero based Compressed Oops.
Universe::set_narrow_oop_use_implicit_null_checks(true);
} else {
// Set to a non-NULL value so the ReservedSpace ctor computes
// the correct no-access prefix.
// The final value will be set in initialize_heap() below.
Universe::set_narrow_oop_base((address)NarrowOopHeapMax);
#ifdef _WIN64
if (UseLargePages) {
// Cannot allocate guard pages for implicit checks in indexed
// addressing mode when large pages are specified on windows.
Universe::set_narrow_oop_use_implicit_null_checks(false);
}
#endif // _WIN64
}
}
#endif
return (char*)base; // also return NULL (don't care) for 32-bit VM
}
jint Universe::initialize_heap() {
if (UseParallelGC) {
#if INCLUDE_ALL_GCS
Universe::_collectedHeap = new ParallelScavengeHeap();
#else // INCLUDE_ALL_GCS
fatal("UseParallelGC not supported in this VM.");
#endif // INCLUDE_ALL_GCS
} else if (UseG1GC) {
#if INCLUDE_ALL_GCS
G1CollectorPolicy* g1p = new G1CollectorPolicy();
G1CollectedHeap* g1h = new G1CollectedHeap(g1p);
Universe::_collectedHeap = g1h;
#else // INCLUDE_ALL_GCS
fatal("UseG1GC not supported in java kernel vm.");
#endif // INCLUDE_ALL_GCS
} else {
GenCollectorPolicy *gc_policy;
if (UseSerialGC) {
gc_policy = new MarkSweepPolicy();
} else if (UseConcMarkSweepGC) {
#if INCLUDE_ALL_GCS
if (UseAdaptiveSizePolicy) {
gc_policy = new ASConcurrentMarkSweepPolicy();
} else {
gc_policy = new ConcurrentMarkSweepPolicy();
}
#else // INCLUDE_ALL_GCS
fatal("UseConcMarkSweepGC not supported in this VM.");
#endif // INCLUDE_ALL_GCS
} else { // default old generation
gc_policy = new MarkSweepPolicy();
}
Universe::_collectedHeap = new GenCollectedHeap(gc_policy);
}
jint status = Universe::heap()->initialize();
if (status != JNI_OK) {
return status;
}
#ifdef _LP64
if (UseCompressedOops) {
// Subtract a page because something can get allocated at heap base.
// This also makes implicit null checking work, because the
// memory+1 page below heap_base needs to cause a signal.
// See needs_explicit_null_check.
// Only set the heap base for compressed oops because it indicates
// compressed oops for pstack code.
bool verbose = PrintCompressedOopsMode || (PrintMiscellaneous && Verbose);
if (verbose) {
tty->cr();
tty->print("heap address: " PTR_FORMAT ", size: " SIZE_FORMAT " MB",
Universe::heap()->base(), Universe::heap()->reserved_region().byte_size()/M);
}
if (((uint64_t)Universe::heap()->reserved_region().end() > OopEncodingHeapMax)) {
// Can't reserve heap below 32Gb.
// keep the Universe::narrow_oop_base() set in Universe::reserve_heap()
Universe::set_narrow_oop_shift(LogMinObjAlignmentInBytes);
if (verbose) {
tty->print(", %s: "PTR_FORMAT,
narrow_oop_mode_to_string(HeapBasedNarrowOop),
Universe::narrow_oop_base());
}
} else {
Universe::set_narrow_oop_base(0);
if (verbose) {
tty->print(", %s", narrow_oop_mode_to_string(ZeroBasedNarrowOop));
}
#ifdef _WIN64
if (!Universe::narrow_oop_use_implicit_null_checks()) {
// Don't need guard page for implicit checks in indexed addressing
// mode with zero based Compressed Oops.
Universe::set_narrow_oop_use_implicit_null_checks(true);
}
#endif // _WIN64
if((uint64_t)Universe::heap()->reserved_region().end() > NarrowOopHeapMax) {
// Can't reserve heap below 4Gb.
Universe::set_narrow_oop_shift(LogMinObjAlignmentInBytes);
} else {
Universe::set_narrow_oop_shift(0);
if (verbose) {
tty->print(", %s", narrow_oop_mode_to_string(UnscaledNarrowOop));
}
}
}
if (verbose) {
tty->cr();
tty->cr();
}
Universe::set_narrow_ptrs_base(Universe::narrow_oop_base());
}
// Universe::narrow_oop_base() is one page below the heap.
assert((intptr_t)Universe::narrow_oop_base() <= (intptr_t)(Universe::heap()->base() -
os::vm_page_size()) ||
Universe::narrow_oop_base() == NULL, "invalid value");
assert(Universe::narrow_oop_shift() == LogMinObjAlignmentInBytes ||
Universe::narrow_oop_shift() == 0, "invalid value");
#endif
// We will never reach the CATCH below since Exceptions::_throw will cause
// the VM to exit if an exception is thrown during initialization
if (UseTLAB) {
assert(Universe::heap()->supports_tlab_allocation(),
"Should support thread-local allocation buffers");
ThreadLocalAllocBuffer::startup_initialization();
}
return JNI_OK;
}
// Reserve the Java heap, which is now the same for all GCs.
ReservedSpace Universe::reserve_heap(size_t heap_size, size_t alignment) {
size_t total_reserved = align_size_up(heap_size, alignment);
assert(!UseCompressedOops || (total_reserved <= (OopEncodingHeapMax - os::vm_page_size())),
"heap size is too big for compressed oops");
char* addr = Universe::preferred_heap_base(total_reserved, Universe::UnscaledNarrowOop);
ReservedHeapSpace total_rs(total_reserved, alignment, UseLargePages, addr);
if (UseCompressedOops) {
if (addr != NULL && !total_rs.is_reserved()) {
// Failed to reserve at specified address - the requested memory
// region is taken already, for example, by 'java' launcher.
// Try again to reserver heap higher.
addr = Universe::preferred_heap_base(total_reserved, Universe::ZeroBasedNarrowOop);
ReservedHeapSpace total_rs0(total_reserved, alignment,
UseLargePages, addr);
if (addr != NULL && !total_rs0.is_reserved()) {
// Failed to reserve at specified address again - give up.
addr = Universe::preferred_heap_base(total_reserved, Universe::HeapBasedNarrowOop);
assert(addr == NULL, "");
ReservedHeapSpace total_rs1(total_reserved, alignment,
UseLargePages, addr);
total_rs = total_rs1;
} else {
total_rs = total_rs0;
}
}
}
if (!total_rs.is_reserved()) {
vm_exit_during_initialization(err_msg("Could not reserve enough space for " SIZE_FORMAT "KB object heap", total_reserved/K));
return total_rs;
}
if (UseCompressedOops) {
// Universe::initialize_heap() will reset this to NULL if unscaled
// or zero-based narrow oops are actually used.
address base = (address)(total_rs.base() - os::vm_page_size());
Universe::set_narrow_oop_base(base);
}
return total_rs;
}
// It's the caller's responsibility to ensure glitch-freedom
// (if required).
void Universe::update_heap_info_at_gc() {
_heap_capacity_at_last_gc = heap()->capacity();
_heap_used_at_last_gc = heap()->used();
}
const char* Universe::narrow_oop_mode_to_string(Universe::NARROW_OOP_MODE mode) {
switch (mode) {
case UnscaledNarrowOop:
return "32-bits Oops";
case ZeroBasedNarrowOop:
return "zero based Compressed Oops";
case HeapBasedNarrowOop:
return "Compressed Oops with base";
}
ShouldNotReachHere();
return "";
}
Universe::NARROW_OOP_MODE Universe::narrow_oop_mode() {
if (narrow_oop_base() != 0) {
return HeapBasedNarrowOop;
}
if (narrow_oop_shift() != 0) {
return ZeroBasedNarrowOop;
}
return UnscaledNarrowOop;
}
void universe2_init() {
EXCEPTION_MARK;
Universe::genesis(CATCH);
}
// This function is defined in JVM.cpp
extern void initialize_converter_functions();
bool universe_post_init() {
assert(!is_init_completed(), "Error: initialization not yet completed!");
Universe::_fully_initialized = true;
EXCEPTION_MARK;
{ ResourceMark rm;
Interpreter::initialize(); // needed for interpreter entry points
if (!UseSharedSpaces) {
HandleMark hm(THREAD);
KlassHandle ok_h(THREAD, SystemDictionary::Object_klass());
Universe::reinitialize_vtable_of(ok_h, CHECK_false);
Universe::reinitialize_itables(CHECK_false);
}
}
HandleMark hm(THREAD);
Klass* k;
instanceKlassHandle k_h;
// Setup preallocated empty java.lang.Class array
Universe::_the_empty_class_klass_array = oopFactory::new_objArray(SystemDictionary::Class_klass(), 0, CHECK_false);
// Setup preallocated OutOfMemoryError errors
k = SystemDictionary::resolve_or_fail(vmSymbols::java_lang_OutOfMemoryError(), true, CHECK_false);
k_h = instanceKlassHandle(THREAD, k);
Universe::_out_of_memory_error_java_heap = k_h->allocate_instance(CHECK_false);
Universe::_out_of_memory_error_metaspace = k_h->allocate_instance(CHECK_false);
Universe::_out_of_memory_error_class_metaspace = k_h->allocate_instance(CHECK_false);
Universe::_out_of_memory_error_array_size = k_h->allocate_instance(CHECK_false);
Universe::_out_of_memory_error_gc_overhead_limit =
k_h->allocate_instance(CHECK_false);
// Setup preallocated NullPointerException
// (this is currently used for a cheap & dirty solution in compiler exception handling)
k = SystemDictionary::resolve_or_fail(vmSymbols::java_lang_NullPointerException(), true, CHECK_false);
Universe::_null_ptr_exception_instance = InstanceKlass::cast(k)->allocate_instance(CHECK_false);
// Setup preallocated ArithmeticException
// (this is currently used for a cheap & dirty solution in compiler exception handling)
k = SystemDictionary::resolve_or_fail(vmSymbols::java_lang_ArithmeticException(), true, CHECK_false);
Universe::_arithmetic_exception_instance = InstanceKlass::cast(k)->allocate_instance(CHECK_false);
// Virtual Machine Error for when we get into a situation we can't resolve
k = SystemDictionary::resolve_or_fail(
vmSymbols::java_lang_VirtualMachineError(), true, CHECK_false);
bool linked = InstanceKlass::cast(k)->link_class_or_fail(CHECK_false);
if (!linked) {
tty->print_cr("Unable to link/verify VirtualMachineError class");
return false; // initialization failed
}
Universe::_virtual_machine_error_instance =
InstanceKlass::cast(k)->allocate_instance(CHECK_false);
Universe::_vm_exception = InstanceKlass::cast(k)->allocate_instance(CHECK_false);
if (!DumpSharedSpaces) {
// These are the only Java fields that are currently set during shared space dumping.
// We prefer to not handle this generally, so we always reinitialize these detail messages.
Handle msg = java_lang_String::create_from_str("Java heap space", CHECK_false);
java_lang_Throwable::set_message(Universe::_out_of_memory_error_java_heap, msg());
msg = java_lang_String::create_from_str("Metadata space", CHECK_false);
java_lang_Throwable::set_message(Universe::_out_of_memory_error_metaspace, msg());
msg = java_lang_String::create_from_str("Class Metadata space", CHECK_false);
java_lang_Throwable::set_message(Universe::_out_of_memory_error_class_metaspace, msg());
msg = java_lang_String::create_from_str("Requested array size exceeds VM limit", CHECK_false);
java_lang_Throwable::set_message(Universe::_out_of_memory_error_array_size, msg());
msg = java_lang_String::create_from_str("GC overhead limit exceeded", CHECK_false);
java_lang_Throwable::set_message(Universe::_out_of_memory_error_gc_overhead_limit, msg());
msg = java_lang_String::create_from_str("/ by zero", CHECK_false);
java_lang_Throwable::set_message(Universe::_arithmetic_exception_instance, msg());
// Setup the array of errors that have preallocated backtrace
k = Universe::_out_of_memory_error_java_heap->klass();
assert(k->name() == vmSymbols::java_lang_OutOfMemoryError(), "should be out of memory error");
k_h = instanceKlassHandle(THREAD, k);
int len = (StackTraceInThrowable) ? (int)PreallocatedOutOfMemoryErrorCount : 0;
Universe::_preallocated_out_of_memory_error_array = oopFactory::new_objArray(k_h(), len, CHECK_false);
for (int i=0; i<len; i++) {
oop err = k_h->allocate_instance(CHECK_false);
Handle err_h = Handle(THREAD, err);
java_lang_Throwable::allocate_backtrace(err_h, CHECK_false);
Universe::preallocated_out_of_memory_errors()->obj_at_put(i, err_h());
}
Universe::_preallocated_out_of_memory_error_avail_count = (jint)len;
}
// Setup static method for registering finalizers
// The finalizer klass must be linked before looking up the method, in
// case it needs to get rewritten.
InstanceKlass::cast(SystemDictionary::Finalizer_klass())->link_class(CHECK_false);
Method* m = InstanceKlass::cast(SystemDictionary::Finalizer_klass())->find_method(
vmSymbols::register_method_name(),
vmSymbols::register_method_signature());
if (m == NULL || !m->is_static()) {
tty->print_cr("Unable to link/verify Finalizer.register method");
return false; // initialization failed (cannot throw exception yet)
}
Universe::_finalizer_register_cache->init(
SystemDictionary::Finalizer_klass(), m);
// Setup method for registering loaded classes in class loader vector
InstanceKlass::cast(SystemDictionary::ClassLoader_klass())->link_class(CHECK_false);
m = InstanceKlass::cast(SystemDictionary::ClassLoader_klass())->find_method(vmSymbols::addClass_name(), vmSymbols::class_void_signature());
if (m == NULL || m->is_static()) {
tty->print_cr("Unable to link/verify ClassLoader.addClass method");
return false; // initialization failed (cannot throw exception yet)
}
Universe::_loader_addClass_cache->init(
SystemDictionary::ClassLoader_klass(), m);
// Setup method for checking protection domain
InstanceKlass::cast(SystemDictionary::ProtectionDomain_klass())->link_class(CHECK_false);
m = InstanceKlass::cast(SystemDictionary::ProtectionDomain_klass())->
find_method(vmSymbols::impliesCreateAccessControlContext_name(),
vmSymbols::void_boolean_signature());
// Allow NULL which should only happen with bootstrapping.
if (m != NULL) {
if (m->is_static()) {
// NoSuchMethodException doesn't actually work because it tries to run the
// <init> function before java_lang_Class is linked. Print error and exit.
tty->print_cr("ProtectionDomain.impliesCreateAccessControlContext() has the wrong linkage");
return false; // initialization failed
}
Universe::_pd_implies_cache->init(
SystemDictionary::ProtectionDomain_klass(), m);;
}
// The folowing is initializing converter functions for serialization in
// JVM.cpp. If we clean up the StrictMath code above we may want to find
// a better solution for this as well.
initialize_converter_functions();
// This needs to be done before the first scavenge/gc, since
// it's an input to soft ref clearing policy.
{
MutexLocker x(Heap_lock);
Universe::update_heap_info_at_gc();
}
// ("weak") refs processing infrastructure initialization
Universe::heap()->post_initialize();
// Initialize performance counters for metaspaces
MetaspaceCounters::initialize_performance_counters();
MemoryService::add_metaspace_memory_pools();
GC_locker::unlock(); // allow gc after bootstrapping
MemoryService::set_universe_heap(Universe::_collectedHeap);
return true;
}
void Universe::compute_base_vtable_size() {
_base_vtable_size = ClassLoader::compute_Object_vtable();
}
// %%% The Universe::flush_foo methods belong in CodeCache.
// Flushes compiled methods dependent on dependee.
void Universe::flush_dependents_on(instanceKlassHandle dependee) {
assert_lock_strong(Compile_lock);
if (CodeCache::number_of_nmethods_with_dependencies() == 0) return;
// CodeCache can only be updated by a thread_in_VM and they will all be
// stopped dring the safepoint so CodeCache will be safe to update without
// holding the CodeCache_lock.
KlassDepChange changes(dependee);
// Compute the dependent nmethods
if (CodeCache::mark_for_deoptimization(changes) > 0) {
// At least one nmethod has been marked for deoptimization
VM_Deoptimize op;
VMThread::execute(&op);
}
}
// Flushes compiled methods dependent on a particular CallSite
// instance when its target is different than the given MethodHandle.
void Universe::flush_dependents_on(Handle call_site, Handle method_handle) {
assert_lock_strong(Compile_lock);
if (CodeCache::number_of_nmethods_with_dependencies() == 0) return;
// CodeCache can only be updated by a thread_in_VM and they will all be
// stopped dring the safepoint so CodeCache will be safe to update without
// holding the CodeCache_lock.
CallSiteDepChange changes(call_site(), method_handle());
// Compute the dependent nmethods that have a reference to a
// CallSite object. We use InstanceKlass::mark_dependent_nmethod
// directly instead of CodeCache::mark_for_deoptimization because we
// want dependents on the call site class only not all classes in
// the ContextStream.
int marked = 0;
{
MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
InstanceKlass* call_site_klass = InstanceKlass::cast(call_site->klass());
marked = call_site_klass->mark_dependent_nmethods(changes);
}
if (marked > 0) {
// At least one nmethod has been marked for deoptimization
VM_Deoptimize op;
VMThread::execute(&op);
}
}
#ifdef HOTSWAP
// Flushes compiled methods dependent on dependee in the evolutionary sense
void Universe::flush_evol_dependents_on(instanceKlassHandle ev_k_h) {
// --- Compile_lock is not held. However we are at a safepoint.
assert_locked_or_safepoint(Compile_lock);
if (CodeCache::number_of_nmethods_with_dependencies() == 0) return;
// CodeCache can only be updated by a thread_in_VM and they will all be
// stopped dring the safepoint so CodeCache will be safe to update without
// holding the CodeCache_lock.
// Compute the dependent nmethods
if (CodeCache::mark_for_evol_deoptimization(ev_k_h) > 0) {
// At least one nmethod has been marked for deoptimization
// All this already happens inside a VM_Operation, so we'll do all the work here.
// Stuff copied from VM_Deoptimize and modified slightly.
// We do not want any GCs to happen while we are in the middle of this VM operation
ResourceMark rm;
DeoptimizationMarker dm;
// Deoptimize all activations depending on marked nmethods
Deoptimization::deoptimize_dependents();
// Make the dependent methods not entrant (in VM_Deoptimize they are made zombies)
CodeCache::make_marked_nmethods_not_entrant();
}
}
#endif // HOTSWAP
// Flushes compiled methods dependent on dependee
void Universe::flush_dependents_on_method(methodHandle m_h) {
// --- Compile_lock is not held. However we are at a safepoint.
assert_locked_or_safepoint(Compile_lock);
// CodeCache can only be updated by a thread_in_VM and they will all be
// stopped dring the safepoint so CodeCache will be safe to update without
// holding the CodeCache_lock.
// Compute the dependent nmethods
if (CodeCache::mark_for_deoptimization(m_h()) > 0) {
// At least one nmethod has been marked for deoptimization
// All this already happens inside a VM_Operation, so we'll do all the work here.
// Stuff copied from VM_Deoptimize and modified slightly.
// We do not want any GCs to happen while we are in the middle of this VM operation
ResourceMark rm;
DeoptimizationMarker dm;
// Deoptimize all activations depending on marked nmethods
Deoptimization::deoptimize_dependents();
// Make the dependent methods not entrant (in VM_Deoptimize they are made zombies)
CodeCache::make_marked_nmethods_not_entrant();
}
}
void Universe::print() {
print_on(gclog_or_tty);
}
void Universe::print_on(outputStream* st, bool extended) {
st->print_cr("Heap");
if (!extended) {
heap()->print_on(st);
} else {
heap()->print_extended_on(st);
}
}
void Universe::print_heap_at_SIGBREAK() {
if (PrintHeapAtSIGBREAK) {
MutexLocker hl(Heap_lock);
print_on(tty);
tty->cr();
tty->flush();
}
}
void Universe::print_heap_before_gc(outputStream* st, bool ignore_extended) {
st->print_cr("{Heap before GC invocations=%u (full %u):",
heap()->total_collections(),
heap()->total_full_collections());
if (!PrintHeapAtGCExtended || ignore_extended) {
heap()->print_on(st);
} else {
heap()->print_extended_on(st);
}
}
void Universe::print_heap_after_gc(outputStream* st, bool ignore_extended) {
st->print_cr("Heap after GC invocations=%u (full %u):",
heap()->total_collections(),
heap()->total_full_collections());
if (!PrintHeapAtGCExtended || ignore_extended) {
heap()->print_on(st);
} else {
heap()->print_extended_on(st);
}
st->print_cr("}");
}
void Universe::verify(VerifyOption option, const char* prefix, bool silent) {
// The use of _verify_in_progress is a temporary work around for
// 6320749. Don't bother with a creating a class to set and clear
// it since it is only used in this method and the control flow is
// straight forward.
_verify_in_progress = true;
COMPILER2_PRESENT(
assert(!DerivedPointerTable::is_active(),
"DPT should not be active during verification "
"(of thread stacks below)");
)
ResourceMark rm;
HandleMark hm; // Handles created during verification can be zapped
_verify_count++;
if (!silent) gclog_or_tty->print(prefix);
if (!silent) gclog_or_tty->print("[Verifying ");
if (!silent) gclog_or_tty->print("threads ");
Threads::verify();
if (!silent) gclog_or_tty->print("heap ");
heap()->verify(silent, option);
if (!silent) gclog_or_tty->print("syms ");
SymbolTable::verify();
if (!silent) gclog_or_tty->print("strs ");
StringTable::verify();
{
MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
if (!silent) gclog_or_tty->print("zone ");
CodeCache::verify();
}
if (!silent) gclog_or_tty->print("dict ");
SystemDictionary::verify();
#ifndef PRODUCT
if (!silent) gclog_or_tty->print("cldg ");
ClassLoaderDataGraph::verify();
#endif
if (!silent) gclog_or_tty->print("metaspace chunks ");
MetaspaceAux::verify_free_chunks();
if (!silent) gclog_or_tty->print("hand ");
JNIHandles::verify();
if (!silent) gclog_or_tty->print("C-heap ");
os::check_heap();
if (!silent) gclog_or_tty->print("code cache ");
CodeCache::verify_oops();
if (!silent) gclog_or_tty->print_cr("]");
_verify_in_progress = false;
}
// Oop verification (see MacroAssembler::verify_oop)
static uintptr_t _verify_oop_data[2] = {0, (uintptr_t)-1};
static uintptr_t _verify_klass_data[2] = {0, (uintptr_t)-1};
#ifndef PRODUCT
static void calculate_verify_data(uintptr_t verify_data[2],
HeapWord* low_boundary,
HeapWord* high_boundary) {
assert(low_boundary < high_boundary, "bad interval");
// decide which low-order bits we require to be clear:
size_t alignSize = MinObjAlignmentInBytes;
size_t min_object_size = CollectedHeap::min_fill_size();
// make an inclusive limit:
uintptr_t max = (uintptr_t)high_boundary - min_object_size*wordSize;
uintptr_t min = (uintptr_t)low_boundary;
assert(min < max, "bad interval");
uintptr_t diff = max ^ min;
// throw away enough low-order bits to make the diff vanish
uintptr_t mask = (uintptr_t)(-1);
while ((mask & diff) != 0)
mask <<= 1;
uintptr_t bits = (min & mask);
assert(bits == (max & mask), "correct mask");
// check an intermediate value between min and max, just to make sure:
assert(bits == ((min + (max-min)/2) & mask), "correct mask");
// require address alignment, too:
mask |= (alignSize - 1);
if (!(verify_data[0] == 0 && verify_data[1] == (uintptr_t)-1)) {
assert(verify_data[0] == mask && verify_data[1] == bits, "mask stability");
}
verify_data[0] = mask;
verify_data[1] = bits;
}
// Oop verification (see MacroAssembler::verify_oop)
uintptr_t Universe::verify_oop_mask() {
MemRegion m = heap()->reserved_region();
calculate_verify_data(_verify_oop_data,
m.start(),
m.end());
return _verify_oop_data[0];
}
uintptr_t Universe::verify_oop_bits() {
verify_oop_mask();
return _verify_oop_data[1];
}
uintptr_t Universe::verify_mark_mask() {
return markOopDesc::lock_mask_in_place;
}
uintptr_t Universe::verify_mark_bits() {
intptr_t mask = verify_mark_mask();
intptr_t bits = (intptr_t)markOopDesc::prototype();
assert((bits & ~mask) == 0, "no stray header bits");
return bits;
}
#endif // PRODUCT
void Universe::compute_verify_oop_data() {
verify_oop_mask();
verify_oop_bits();
verify_mark_mask();
verify_mark_bits();
}
void LatestMethodCache::init(Klass* k, Method* m) {
if (!UseSharedSpaces) {
_klass = k;
}
#ifndef PRODUCT
else {
// sharing initilization should have already set up _klass
assert(_klass != NULL, "just checking");
}
#endif
_method_idnum = m->method_idnum();
assert(_method_idnum >= 0, "sanity check");
}
Method* LatestMethodCache::get_method() {
if (klass() == NULL) return NULL;
InstanceKlass* ik = InstanceKlass::cast(klass());
Method* m = ik->method_with_idnum(method_idnum());
assert(m != NULL, "sanity check");
return m;
}
#ifdef ASSERT
// Release dummy object(s) at bottom of heap
bool Universe::release_fullgc_alot_dummy() {
MutexLocker ml(FullGCALot_lock);
if (_fullgc_alot_dummy_array != NULL) {
if (_fullgc_alot_dummy_next >= _fullgc_alot_dummy_array->length()) {
// No more dummies to release, release entire array instead
_fullgc_alot_dummy_array = NULL;
return false;
}
if (!UseConcMarkSweepGC) {
// Release dummy at bottom of old generation
_fullgc_alot_dummy_array->obj_at_put(_fullgc_alot_dummy_next++, NULL);
}
// Release dummy at bottom of permanent generation
_fullgc_alot_dummy_array->obj_at_put(_fullgc_alot_dummy_next++, NULL);
}
return true;
}
#endif // ASSERT