< prev index next > src/hotspot/share/memory/heapShared.cpp
Print this page
#include "memory/metaspaceShared.hpp"
#include "memory/resourceArea.hpp"
#include "memory/universe.hpp"
#include "oops/compressedOops.inline.hpp"
#include "oops/fieldStreams.inline.hpp"
+ #include "oops/objArrayOop.hpp"
#include "oops/oop.inline.hpp"
+ #include "oops/oopHandle.hpp"
#include "runtime/fieldDescriptor.inline.hpp"
+ #include "runtime/init.hpp"
#include "runtime/javaCalls.hpp"
#include "runtime/safepointVerifiers.hpp"
#include "utilities/bitMap.inline.hpp"
#if INCLUDE_G1GC
#include "gc/g1/g1CollectedHeap.hpp"
const static int num_open_archive_subgraph_entry_fields =
sizeof(open_archive_subgraph_entry_fields) / sizeof(ArchivableStaticFieldInfo);
const static int num_fmg_open_archive_subgraph_entry_fields =
sizeof(fmg_open_archive_subgraph_entry_fields) / sizeof(ArchivableStaticFieldInfo);
+ static GrowableArrayCHeap<oop, mtClassShared>* _pending_roots = NULL;
+ static objArrayOop _dumptime_roots = NULL; // FIXME -- combine this with _runtime_roots??
+ static narrowOop _runtime_roots_narrow;
+ static OopHandle _runtime_roots;
+
////////////////////////////////////////////////////////////////
//
// Java heap object archiving support
//
////////////////////////////////////////////////////////////////
void HeapShared::fixup_mapped_heap_regions() {
FileMapInfo *mapinfo = FileMapInfo::current_info();
mapinfo->fixup_mapped_heap_regions();
set_archive_heap_region_fixed();
+ if (is_mapped()) {
+ _runtime_roots = OopHandle(Universe::vm_global(), HeapShared::materialize_archived_object(_runtime_roots_narrow));
+ if (!MetaspaceShared::use_full_module_graph()) {
+ // Need to remove all the archived java.lang.Module objects from HeapShared::roots().
+ ClassLoaderDataShared::clear_archived_oops();
+ }
+ }
SystemDictionaryShared::update_archived_mirror_native_pointers();
}
unsigned HeapShared::oop_hash(oop const& p) {
assert(!p->mark().has_bias_pattern(),
} else {
return NULL;
}
}
+ int HeapShared::append_root(oop obj) {
+ assert(DumpSharedSpaces, "dump-time only");
+
+ // No GC should happen since we aren't scanning _pending_roots.
+ assert(Thread::current() == (Thread*)VMThread::vm_thread(), "should be in vm thread");
+
+ if (_pending_roots == NULL) {
+ _pending_roots = new GrowableArrayCHeap<oop, mtClassShared>(500);
+ }
+
+ return _pending_roots->append(obj);
+ }
+
+ objArrayOop HeapShared::roots() {
+ if (DumpSharedSpaces) {
+ assert(Thread::current() == (Thread*)VMThread::vm_thread(), "should be in vm thread");
+ return _dumptime_roots;
+ } else {
+ assert(UseSharedSpaces, "must be");
+ objArrayOop roots = (objArrayOop)_runtime_roots.resolve();
+ assert(roots != NULL, "should have been initialized");
+ return roots;
+ }
+ }
+
+ void HeapShared::set_roots(narrowOop roots) {
+ assert(UseSharedSpaces, "runtime only");
+ assert(open_archive_heap_region_mapped(), "must be");
+ _runtime_roots_narrow = roots;
+ }
+
+ oop HeapShared::get_root(int index, bool clear) {
+ assert(index >= 0, "sanity");
+ if (DumpSharedSpaces) {
+ assert(Thread::current() == (Thread*)VMThread::vm_thread(), "should be in vm thread");
+ assert(_pending_roots != NULL, "sanity");
+ return _pending_roots->at(index);
+ } else {
+ assert(UseSharedSpaces, "must be");
+ assert(!_runtime_roots.is_empty(), "must have loaded shared heap");
+ oop result = roots()->obj_at(index);
+ if (clear) {
+ clear_root(index);
+ }
+ return result;
+ }
+ }
+
+ void HeapShared::clear_root(int index) {
+ assert(index >= 0, "sanity");
+ assert(UseSharedSpaces, "must be");
+ if (open_archive_heap_region_mapped()) {
+ if (log_is_enabled(Debug, cds, heap)) {
+ oop old = roots()->obj_at(index);
+ log_debug(cds, heap)("Clearing root %d: was " PTR_FORMAT, index, p2i(old));
+ }
+ roots()->obj_at_put(index, NULL);
+ }
+ }
+
oop HeapShared::archive_heap_object(oop obj, Thread* THREAD) {
assert(DumpSharedSpaces, "dump-time only");
oop ao = find_archived_heap_object(obj);
if (ao != NULL) {
DEBUG_ONLY(int hash_archived = archived_oop->identity_hash());
assert(hash_original == hash_archived, "Different hash codes: original %x, archived %x", hash_original, hash_archived);
ArchivedObjectCache* cache = archived_object_cache();
cache->put(obj, archived_oop);
- log_debug(cds, heap)("Archived heap object " PTR_FORMAT " ==> " PTR_FORMAT,
- p2i(obj), p2i(archived_oop));
+ if (log_is_enabled(Debug, cds, heap)) {
+ ResourceMark rm;
+ log_debug(cds, heap)("Archived heap object " PTR_FORMAT " ==> " PTR_FORMAT " : %s",
+ p2i(obj), p2i(archived_oop), obj->klass()->external_name());
+ }
} else {
log_error(cds, heap)(
"Cannot allocate space for object " PTR_FORMAT " in archived heap region",
p2i(obj));
vm_exit(1);
log_info(cds)("Run GC done");
}
}
}
+ // Returns an objArray that contains all the roots of the archived objects
void HeapShared::archive_java_heap_objects(GrowableArray<MemRegion> *closed,
GrowableArray<MemRegion> *open) {
if (!is_heap_object_archiving_allowed()) {
log_info(cds)(
"Archived java heap is not supported as UseG1GC, "
copy_closed_archive_heap_objects(closed);
log_info(cds)("Dumping objects to open archive heap region ...");
copy_open_archive_heap_objects(open);
- if (MetaspaceShared::use_full_module_graph()) {
- ClassLoaderDataShared::init_archived_oops();
- }
-
destroy_archived_object_cache();
}
G1HeapVerifier::verify_archive_regions();
}
archive_object_subgraphs(fmg_open_archive_subgraph_entry_fields,
num_fmg_open_archive_subgraph_entry_fields,
false /* is_closed_archive */,
true /* is_full_module_graph */,
THREAD);
+ ClassLoaderDataShared::init_archived_oops();
}
+ copy_roots();
+
G1CollectedHeap::heap()->end_archive_alloc_range(open_archive,
os::vm_allocation_granularity());
}
+ // Copy _pending_archive_roots into an objArray
+ void HeapShared::copy_roots() {
+ int length = _pending_roots != NULL ? _pending_roots->length() : 0;
+ int size = objArrayOopDesc::object_size(length);
+ Klass *k = Universe::objectArrayKlassObj(); // already relocated to point to archived klass
+ HeapWord* mem = G1CollectedHeap::heap()->archive_mem_allocate(size);
+
+ memset(mem, 0, size * BytesPerWord); // Is this correct??
+ {
+ // This is copied from MemAllocator::finish
+ if (UseBiasedLocking) {
+ oopDesc::set_mark(mem, k->prototype_header());
+ } else {
+ oopDesc::set_mark(mem, markWord::prototype());
+ }
+ oopDesc::release_set_klass(mem, k);
+ }
+ {
+ // This is copied from ObjArrayAllocator::initialize
+ arrayOopDesc::set_length(mem, length);
+ }
+
+ _dumptime_roots = (objArrayOop)mem;
+ for (int i = 0; i < length; i++) {
+ _dumptime_roots->obj_at_put(i, _pending_roots->at(i));
+ }
+ log_info(cds)("archived obj roots[%d] = %d words, klass = %p, obj = %p", length, size, k, mem);
+ }
+
void HeapShared::init_narrow_oop_decoding(address base, int shift) {
_narrow_oop_base = base;
_narrow_oop_shift = shift;
}
void KlassSubGraphInfo::add_subgraph_entry_field(
int static_field_offset, oop v, bool is_closed_archive) {
assert(DumpSharedSpaces, "dump time only");
if (_subgraph_entry_fields == NULL) {
_subgraph_entry_fields =
- new(ResourceObj::C_HEAP, mtClass) GrowableArray<juint>(10, mtClass);
+ new(ResourceObj::C_HEAP, mtClass) GrowableArray<int>(10, mtClass);
}
- _subgraph_entry_fields->append((juint)static_field_offset);
- _subgraph_entry_fields->append(CompressedOops::narrow_oop_value(v));
+ _subgraph_entry_fields->append(static_field_offset);
+ _subgraph_entry_fields->append(HeapShared::append_root(v));
_subgraph_entry_fields->append(is_closed_archive ? 1 : 0);
}
// Add the Klass* for an object in the current KlassSubGraphInfo's subgraphs.
// Only objects of boot classes can be included in sub-graph.
log_debug(cds, heap)("Adding klass %s", orig_k->external_name());
}
}
_subgraph_object_klasses->append_if_missing(relocated_k);
+ _has_non_early_klasses |= is_non_early_klass(orig_k);
+ }
+
+ bool KlassSubGraphInfo::is_non_early_klass(Klass* k) {
+ if (k->is_objArray_klass()) {
+ k = ObjArrayKlass::cast(k)->bottom_klass();
+ }
+ if (k->is_instance_klass()) {
+ if (!SystemDictionaryShared::is_early_klass(InstanceKlass::cast(k))) {
+ ResourceMark rm;
+ log_info(cds, heap)("non-early: %s", k->external_name());
+ return true;
+ } else {
+ return false;
+ }
+ } else {
+ return false;
+ }
}
// Initialize an archived subgraph_info_record from the given KlassSubGraphInfo.
void ArchivedKlassSubGraphInfoRecord::init(KlassSubGraphInfo* info) {
_k = info->klass();
_entry_field_records = NULL;
_subgraph_object_klasses = NULL;
_is_full_module_graph = info->is_full_module_graph();
+ _has_non_early_klasses = info->has_non_early_klasses();
+
+ if (_has_non_early_klasses) {
+ ResourceMark rm;
+ log_info(cds, heap)(
+ "Subgraph of klass %s has non-early klasses and cannot be used when JVMTI ClassFileLoadHook is enabled",
+ _k->external_name());
+ }
// populate the entry fields
- GrowableArray<juint>* entry_fields = info->subgraph_entry_fields();
+ GrowableArray<int>* entry_fields = info->subgraph_entry_fields();
if (entry_fields != NULL) {
int num_entry_fields = entry_fields->length();
assert(num_entry_fields % 3 == 0, "sanity");
_entry_field_records =
- MetaspaceShared::new_ro_array<juint>(num_entry_fields);
+ MetaspaceShared::new_ro_array<int>(num_entry_fields);
for (int i = 0 ; i < num_entry_fields; i++) {
_entry_field_records->at_put(i, entry_fields->at(i));
}
}
void HeapShared::serialize_subgraph_info_table_header(SerializeClosure* soc) {
_run_time_subgraph_info_table.serialize_header(soc);
}
+ static void verify_the_heap(Klass* k, const char* which) {
+ if (VerifyArchivedFields) {
+ ResourceMark rm;
+ log_info(cds, heap)("Verify heap %s initializing static field(s) in %s",
+ which, k->external_name());
+ VM_Verify verify_op;
+ VMThread::execute(&verify_op);
+ #if 0
+ // For some reason, this causes jtreg to lock up with
+ // "jtreg -vmoptions:-XX:+VerifyArchivedFields HelloTest.java"
+ if (is_init_completed()) {
+ FlagSetting fs1(VerifyBeforeGC, true);
+ FlagSetting fs2(VerifyDuringGC, true);
+ FlagSetting fs3(VerifyAfterGC, true);
+ Universe::heap()->collect(GCCause::_java_lang_system_gc);
+ }
+ #endif
+ }
+ }
+
+ // Before GC can execute, we must ensure that all oops reachable from HeapShared::roots()
+ // have a valid klass. I.e., oopDesc::klass() must have already been resolved.
+ //
+ // Note: if a ArchivedKlassSubGraphInfoRecord contains non-early classes, and JVMTI
+ // ClassFileLoadHook is enabled, it's possible for this class to be dynamically replaced. In
+ // this case, we will not load the ArchivedKlassSubGraphInfoRecord and will clear its roots.
+ void HeapShared::resolve_classes(TRAPS) {
+ if (!is_mapped()) {
+ return; // nothing to do
+ }
+ resolve_classes_for_subgraphs(closed_archive_subgraph_entry_fields,
+ num_closed_archive_subgraph_entry_fields,
+ CHECK);
+ resolve_classes_for_subgraphs(open_archive_subgraph_entry_fields,
+ num_open_archive_subgraph_entry_fields,
+ CHECK);
+ resolve_classes_for_subgraphs(fmg_open_archive_subgraph_entry_fields,
+ num_fmg_open_archive_subgraph_entry_fields,
+ CHECK);
+ }
+
+ void HeapShared::resolve_classes_for_subgraphs(ArchivableStaticFieldInfo fields[],
+ int num, TRAPS) {
+ for (int i = 0; i < num; i++) {
+ ArchivableStaticFieldInfo* info = &fields[i];
+ TempNewSymbol klass_name = SymbolTable::new_symbol(info->klass_name);
+ InstanceKlass* k = SystemDictionaryShared::find_builtin_class(klass_name);
+ assert(k != NULL && k->is_shared_boot_class(), "sanity");
+ resolve_classes_for_subgraph_of(k, CHECK);
+ }
+ }
+
+ void HeapShared::resolve_classes_for_subgraph_of(Klass* k, TRAPS) {
+ const ArchivedKlassSubGraphInfoRecord* record = resolve_or_init_classes_for_subgraph_of(k, /*do_init=*/false, THREAD);
+ if (HAS_PENDING_EXCEPTION) {
+ CLEAR_PENDING_EXCEPTION;
+ }
+ if (record == NULL) {
+ clear_archived_roots_of(k);
+ }
+ }
+
void HeapShared::initialize_from_archived_subgraph(Klass* k, TRAPS) {
- if (!open_archive_heap_region_mapped()) {
+ if (!is_mapped()) {
return; // nothing to do
}
+
+ const ArchivedKlassSubGraphInfoRecord* record =
+ resolve_or_init_classes_for_subgraph_of(k, /*do_init=*/true, THREAD);
+
+ if (HAS_PENDING_EXCEPTION) {
+ CLEAR_PENDING_EXCEPTION;
+ // None of the field value will be set if there was an exception when initializing the classes.
+ // The java code will not see any of the archived objects in the
+ // subgraphs referenced from k in this case.
+ return;
+ }
+
+ if (record != NULL) {
+ init_archived_fields_for(k, record, THREAD);
+ }
+ }
+
+ const ArchivedKlassSubGraphInfoRecord*
+ HeapShared::resolve_or_init_classes_for_subgraph_of(Klass* k, bool do_init, TRAPS) {
assert(!DumpSharedSpaces, "Should not be called with DumpSharedSpaces");
unsigned int hash = SystemDictionaryShared::hash_for_shared_dictionary(k);
const ArchivedKlassSubGraphInfoRecord* record = _run_time_subgraph_info_table.lookup(k, hash, 0);
// Initialize from archived data. Currently this is done only
// during VM initialization time. No lock is needed.
if (record != NULL) {
if (record->is_full_module_graph() && !MetaspaceShared::use_full_module_graph()) {
- return;
+ if (log_is_enabled(Info, cds, heap)) {
+ ResourceMark rm;
+ log_info(cds, heap)("subgraph %s cannot be used because full module graph is disabled",
+ k->external_name());
+ }
+ return NULL;
}
- int i;
+ if (record->has_non_early_klasses() && JvmtiExport::should_post_class_file_load_hook()) {
+ if (log_is_enabled(Info, cds, heap)) {
+ ResourceMark rm;
+ log_info(cds, heap)("subgraph %s cannot be used because JVMTI ClassFileLoadHook is enabled",
+ k->external_name());
+ }
+ return NULL;
+ }
+
+ resolve_or_init(k, do_init, CHECK_NULL);
+
// Load/link/initialize the klasses of the objects in the subgraph.
// NULL class loader is used.
Array<Klass*>* klasses = record->subgraph_object_klasses();
if (klasses != NULL) {
- for (i = 0; i < klasses->length(); i++) {
- Klass* obj_k = klasses->at(i);
- Klass* resolved_k = SystemDictionary::resolve_or_null(
- (obj_k)->name(), THREAD);
- if (resolved_k != obj_k) {
- assert(!SystemDictionary::is_well_known_klass(resolved_k),
- "shared well-known classes must not be replaced by JVMTI ClassFileLoadHook");
- ResourceMark rm(THREAD);
- log_info(cds, heap)("Failed to load subgraph because %s was not loaded from archive",
- resolved_k->external_name());
- return;
- }
- if ((obj_k)->is_instance_klass()) {
- InstanceKlass* ik = InstanceKlass::cast(obj_k);
- ik->initialize(THREAD);
- } else if ((obj_k)->is_objArray_klass()) {
- ObjArrayKlass* oak = ObjArrayKlass::cast(obj_k);
- oak->initialize(THREAD);
- }
+ for (int i = 0; i < klasses->length(); i++) {
+ resolve_or_init(klasses->at(i), do_init, CHECK_NULL);
}
}
+ }
- if (HAS_PENDING_EXCEPTION) {
- CLEAR_PENDING_EXCEPTION;
- // None of the field value will be set if there was an exception.
- // The java code will not see any of the archived objects in the
- // subgraphs referenced from k in this case.
- return;
+ return record;
+ }
+
+ void HeapShared::resolve_or_init(Klass* k, bool do_init, TRAPS) {
+ if (!do_init) {
+ if (k->class_loader_data() == NULL) {
+ Klass* resolved_k = SystemDictionary::resolve_or_null(k->name(), CHECK);
+ assert(resolved_k == k, "classes used by archived heap must not be replaced by JVMTI ClassFileLoadHook");
+ }
+ } else {
+ assert(k->class_loader_data() != NULL, "must have been resolved by HeapShared::resolve_classes");
+ if (k->is_instance_klass()) {
+ InstanceKlass* ik = InstanceKlass::cast(k);
+ ik->initialize(CHECK);
+ } else if (k->is_objArray_klass()) {
+ ObjArrayKlass* oak = ObjArrayKlass::cast(k);
+ oak->initialize(CHECK);
+ }
+ }
+ }
+
+ void HeapShared::init_archived_fields_for(Klass* k, const ArchivedKlassSubGraphInfoRecord* record, TRAPS) {
+ verify_the_heap(k, "before");
+
+ // Load the subgraph entry fields from the record and store them back to
+ // the corresponding fields within the mirror.
+ oop m = k->java_mirror();
+ Array<int>* entry_field_records = record->entry_field_records();
+ if (entry_field_records != NULL) {
+ int efr_len = entry_field_records->length();
+ assert(efr_len % 3 == 0, "sanity");
+ for (int i = 0; i < efr_len; i += 3) {
+ int field_offset = entry_field_records->at(i);
+ int root_index = entry_field_records->at(i+1);
+ int is_closed_archive = entry_field_records->at(i+2);
+ oop v = get_root(root_index, /*clear=*/true);
+ m->obj_field_put(field_offset, v);
+ log_debug(cds, heap)(" " PTR_FORMAT " init field @ %2d = " PTR_FORMAT, p2i(k), field_offset, p2i(v));
}
- // Load the subgraph entry fields from the record and store them back to
- // the corresponding fields within the mirror.
- oop m = k->java_mirror();
- Array<juint>* entry_field_records = record->entry_field_records();
+ // Done. Java code can see the archived sub-graphs referenced from k's
+ // mirror after this point.
+ if (log_is_enabled(Info, cds, heap)) {
+ ResourceMark rm;
+ log_info(cds, heap)("initialize_from_archived_subgraph %s " PTR_FORMAT "%s",
+ k->external_name(), p2i(k), JvmtiExport::is_early_phase() ? " (early)" : "");
+ }
+ }
+
+ verify_the_heap(k, "after ");
+ }
+
+ void HeapShared::clear_archived_roots_of(Klass* k) {
+ unsigned int hash = SystemDictionaryShared::hash_for_shared_dictionary(k);
+ const ArchivedKlassSubGraphInfoRecord* record = _run_time_subgraph_info_table.lookup(k, hash, 0);
+ if (record != NULL) {
+ Array<int>* entry_field_records = record->entry_field_records();
if (entry_field_records != NULL) {
int efr_len = entry_field_records->length();
assert(efr_len % 3 == 0, "sanity");
- for (i = 0; i < efr_len;) {
- int field_offset = entry_field_records->at(i);
- narrowOop nv = CompressedOops::narrow_oop_cast(entry_field_records->at(i+1));
- int is_closed_archive = entry_field_records->at(i+2);
- oop v;
- if (is_closed_archive == 0) {
- // It's an archived object in the open archive heap regions, not shared.
- // The object refereced by the field becomes 'known' by GC from this
- // point. All objects in the subgraph reachable from the object are
- // also 'known' by GC.
- v = materialize_archived_object(nv);
- } else {
- // Shared object in the closed archive heap regions. Decode directly.
- assert(!CompressedOops::is_null(nv), "shared object is null");
- v = HeapShared::decode_from_archive(nv);
- }
- m->obj_field_put(field_offset, v);
- i += 3;
-
- log_debug(cds, heap)(" " PTR_FORMAT " init field @ %2d = " PTR_FORMAT, p2i(k), field_offset, p2i(v));
- }
-
- // Done. Java code can see the archived sub-graphs referenced from k's
- // mirror after this point.
- if (log_is_enabled(Info, cds, heap)) {
- ResourceMark rm;
- log_info(cds, heap)("initialize_from_archived_subgraph %s " PTR_FORMAT,
- k->external_name(), p2i(k));
+ for (int i = 0; i < efr_len; i += 3) {
+ int root_index = entry_field_records->at(i+1);
+ clear_root(root_index);
}
}
}
}
< prev index next >