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/*
* Copyright (c) 2012, 2022, 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 "cds/archiveBuilder.hpp"
#include "cds/archiveHeapLoader.hpp"
#include "cds/cds_globals.hpp"
#include "cds/cdsProtectionDomain.hpp"
#include "cds/classListWriter.hpp"
#include "cds/classListParser.hpp"
#include "cds/classPrelinker.hpp"
#include "cds/cppVtables.hpp"
#include "cds/dumpAllocStats.hpp"
#include "cds/filemap.hpp"
#include "cds/heapShared.hpp"
#include "cds/lambdaFormInvokers.hpp"
#include "cds/metaspaceShared.hpp"
#include "classfile/classLoaderDataGraph.hpp"
#include "classfile/classLoaderDataShared.hpp"
#include "classfile/classLoaderExt.hpp"
#include "classfile/javaClasses.inline.hpp"
#include "classfile/loaderConstraints.hpp"
#include "classfile/placeholders.hpp"
#include "classfile/symbolTable.hpp"
#include "classfile/stringTable.hpp"
#include "classfile/systemDictionary.hpp"
#include "classfile/systemDictionaryShared.hpp"
#include "classfile/vmClasses.hpp"
#include "classfile/vmSymbols.hpp"
#include "code/codeCache.hpp"
#include "gc/shared/gcVMOperations.hpp"
#include "interpreter/bytecodeStream.hpp"
#include "interpreter/bytecodes.hpp"
#include "jvm_io.h"
#include "logging/log.hpp"
#include "logging/logMessage.hpp"
#include "logging/logStream.hpp"
#include "memory/metaspace.hpp"
#include "memory/metaspaceClosure.hpp"
#include "memory/resourceArea.hpp"
#include "memory/universe.hpp"
#include "oops/compressedOops.inline.hpp"
#include "oops/instanceMirrorKlass.hpp"
#include "oops/klass.inline.hpp"
#include "oops/objArrayOop.hpp"
#include "oops/oop.inline.hpp"
#include "oops/oopHandle.hpp"
#include "prims/jvmtiExport.hpp"
#include "runtime/arguments.hpp"
#include "runtime/globals_extension.hpp"
#include "runtime/handles.inline.hpp"
#include "runtime/os.inline.hpp"
#include "runtime/safepointVerifiers.hpp"
#include "runtime/sharedRuntime.hpp"
#include "runtime/vmThread.hpp"
#include "runtime/vmOperations.hpp"
#include "services/memTracker.hpp"
#include "utilities/align.hpp"
#include "utilities/bitMap.inline.hpp"
#include "utilities/ostream.hpp"
#include "utilities/defaultStream.hpp"
#include "utilities/resourceHash.hpp"
#if INCLUDE_G1GC
#include "gc/g1/g1CollectedHeap.inline.hpp"
#endif
ReservedSpace MetaspaceShared::_symbol_rs;
VirtualSpace MetaspaceShared::_symbol_vs;
bool MetaspaceShared::_has_error_classes;
bool MetaspaceShared::_archive_loading_failed = false;
bool MetaspaceShared::_remapped_readwrite = false;
void* MetaspaceShared::_shared_metaspace_static_top = NULL;
intx MetaspaceShared::_relocation_delta;
char* MetaspaceShared::_requested_base_address;
bool MetaspaceShared::_use_optimized_module_handling = true;
bool MetaspaceShared::_use_full_module_graph = true;
// The CDS archive is divided into the following regions:
// rw - read-write metadata
// ro - read-only metadata and read-only tables
//
// ca0 - closed archive heap space #0
// ca1 - closed archive heap space #1 (may be empty)
// oa0 - open archive heap space #0
// oa1 - open archive heap space #1 (may be empty)
//
// bm - bitmap for relocating the above 7 regions.
//
// The rw and ro regions are linearly allocated, in the order of rw->ro.
// These regions are aligned with MetaspaceShared::core_region_alignment().
//
// These 2 regions are populated in the following steps:
// [0] All classes are loaded in MetaspaceShared::preload_classes(). All metadata are
// temporarily allocated outside of the shared regions.
// [1] We enter a safepoint and allocate a buffer for the rw/ro regions.
// [2] C++ vtables are copied into the rw region.
// [3] ArchiveBuilder copies RW metadata into the rw region.
// [4] ArchiveBuilder copies RO metadata into the ro region.
// [5] SymbolTable, StringTable, SystemDictionary, and a few other read-only data
// are copied into the ro region as read-only tables.
//
// The ca0/ca1 and oa0/oa1 regions are populated inside HeapShared::archive_objects.
// Their layout is independent of the rw/ro regions.
static DumpRegion _symbol_region("symbols");
char* MetaspaceShared::symbol_space_alloc(size_t num_bytes) {
return _symbol_region.allocate(num_bytes);
}
// os::vm_allocation_granularity() is usually 4K for most OSes. However, some platforms
// such as linux-aarch64 and macos-x64 ...
// it can be either 4K or 64K and on macos-aarch64 it is 16K. To generate archives that are
// compatible for both settings, an alternative cds core region alignment can be enabled
// at building time:
// --enable-compactible-cds-alignment
// Upon successful configuration, the compactible alignment then can be defined in:
// os_linux_aarch64.cpp
// os_bsd_x86.cpp
size_t MetaspaceShared::core_region_alignment() {
return os::cds_core_region_alignment();
}
static bool shared_base_valid(char* shared_base) {
#ifdef _LP64
return CompressedKlassPointers::is_valid_base((address)shared_base);
#else
return true;
#endif
}
class DumpClassListCLDClosure : public CLDClosure {
static const int INITIAL_TABLE_SIZE = 1987;
static const int MAX_TABLE_SIZE = 61333;
fileStream *_stream;
ResizeableResourceHashtable<InstanceKlass*, bool,
AnyObj::C_HEAP, mtClassShared> _dumped_classes;
void dump(InstanceKlass* ik) {
bool created;
_dumped_classes.put_if_absent(ik, &created);
if (!created) {
return;
}
if (_dumped_classes.maybe_grow()) {
log_info(cds, hashtables)("Expanded _dumped_classes table to %d", _dumped_classes.table_size());
}
if (ik->java_super()) {
dump(ik->java_super());
}
Array<InstanceKlass*>* interfaces = ik->local_interfaces();
int len = interfaces->length();
for (int i = 0; i < len; i++) {
dump(interfaces->at(i));
}
ClassListWriter::write_to_stream(ik, _stream);
}
public:
DumpClassListCLDClosure(fileStream* f)
: CLDClosure(), _dumped_classes(INITIAL_TABLE_SIZE, MAX_TABLE_SIZE) {
_stream = f;
}
void do_cld(ClassLoaderData* cld) {
for (Klass* klass = cld->klasses(); klass != NULL; klass = klass->next_link()) {
if (klass->is_instance_klass()) {
dump(InstanceKlass::cast(klass));
}
}
}
};
void MetaspaceShared::dump_loaded_classes(const char* file_name, TRAPS) {
fileStream stream(file_name, "w");
if (stream.is_open()) {
MutexLocker lock(ClassLoaderDataGraph_lock);
MutexLocker lock2(ClassListFile_lock, Mutex::_no_safepoint_check_flag);
DumpClassListCLDClosure collect_classes(&stream);
ClassLoaderDataGraph::loaded_cld_do(&collect_classes);
} else {
THROW_MSG(vmSymbols::java_io_IOException(), "Failed to open file");
}
}
static bool shared_base_too_high(char* specified_base, char* aligned_base, size_t cds_max) {
if (specified_base != NULL && aligned_base < specified_base) {
// SharedBaseAddress is very high (e.g., 0xffffffffffffff00) so
// align_up(SharedBaseAddress, MetaspaceShared::core_region_alignment()) has wrapped around.
return true;
}
if (max_uintx - uintx(aligned_base) < uintx(cds_max)) {
// The end of the archive will wrap around
return true;
}
return false;
}
static char* compute_shared_base(size_t cds_max) {
char* specified_base = (char*)SharedBaseAddress;
char* aligned_base = align_up(specified_base, MetaspaceShared::core_region_alignment());
const char* err = NULL;
if (shared_base_too_high(specified_base, aligned_base, cds_max)) {
err = "too high";
} else if (!shared_base_valid(aligned_base)) {
err = "invalid for this platform";
} else {
return aligned_base;
}
log_warning(cds)("SharedBaseAddress (" INTPTR_FORMAT ") is %s. Reverted to " INTPTR_FORMAT,
p2i((void*)SharedBaseAddress), err,
p2i((void*)Arguments::default_SharedBaseAddress()));
specified_base = (char*)Arguments::default_SharedBaseAddress();
aligned_base = align_up(specified_base, MetaspaceShared::core_region_alignment());
// Make sure the default value of SharedBaseAddress specified in globals.hpp is sane.
assert(!shared_base_too_high(specified_base, aligned_base, cds_max), "Sanity");
assert(shared_base_valid(aligned_base), "Sanity");
return aligned_base;
}
void MetaspaceShared::initialize_for_static_dump() {
assert(DumpSharedSpaces, "should be called for dump time only");
log_info(cds)("Core region alignment: " SIZE_FORMAT, core_region_alignment());
// The max allowed size for CDS archive. We use this to limit SharedBaseAddress
// to avoid address space wrap around.
size_t cds_max;
const size_t reserve_alignment = core_region_alignment();
#ifdef _LP64
const uint64_t UnscaledClassSpaceMax = (uint64_t(max_juint) + 1);
cds_max = align_down(UnscaledClassSpaceMax, reserve_alignment);
#else
// We don't support archives larger than 256MB on 32-bit due to limited
// virtual address space.
cds_max = align_down(256*M, reserve_alignment);
#endif
_requested_base_address = compute_shared_base(cds_max);
SharedBaseAddress = (size_t)_requested_base_address;
size_t symbol_rs_size = LP64_ONLY(3 * G) NOT_LP64(128 * M);
_symbol_rs = ReservedSpace(symbol_rs_size);
if (!_symbol_rs.is_reserved()) {
vm_exit_during_initialization("Unable to reserve memory for symbols",
err_msg(SIZE_FORMAT " bytes.", symbol_rs_size));
}
_symbol_region.init(&_symbol_rs, &_symbol_vs);
}
// Called by universe_post_init()
void MetaspaceShared::post_initialize(TRAPS) {
if (UseSharedSpaces) {
int size = FileMapInfo::get_number_of_shared_paths();
if (size > 0) {
CDSProtectionDomain::allocate_shared_data_arrays(size, CHECK);
if (!DynamicDumpSharedSpaces) {
FileMapInfo* info;
if (FileMapInfo::dynamic_info() == NULL) {
info = FileMapInfo::current_info();
} else {
info = FileMapInfo::dynamic_info();
}
ClassLoaderExt::init_paths_start_index(info->app_class_paths_start_index());
ClassLoaderExt::init_app_module_paths_start_index(info->app_module_paths_start_index());
}
}
}
}
static GrowableArrayCHeap<OopHandle, mtClassShared>* _extra_interned_strings = NULL;
static GrowableArrayCHeap<Symbol*, mtClassShared>* _extra_symbols = NULL;
void MetaspaceShared::read_extra_data(JavaThread* current, const char* filename) {
_extra_interned_strings = new GrowableArrayCHeap<OopHandle, mtClassShared>(10000);
_extra_symbols = new GrowableArrayCHeap<Symbol*, mtClassShared>(1000);
HashtableTextDump reader(filename);
reader.check_version("VERSION: 1.0");
while (reader.remain() > 0) {
int utf8_length;
int prefix_type = reader.scan_prefix(&utf8_length);
ResourceMark rm(current);
if (utf8_length == 0x7fffffff) {
// buf_len will overflown 32-bit value.
vm_exit_during_initialization(err_msg("string length too large: %d", utf8_length));
}
int buf_len = utf8_length+1;
char* utf8_buffer = NEW_RESOURCE_ARRAY(char, buf_len);
reader.get_utf8(utf8_buffer, utf8_length);
utf8_buffer[utf8_length] = '\0';
if (prefix_type == HashtableTextDump::SymbolPrefix) {
_extra_symbols->append(SymbolTable::new_permanent_symbol(utf8_buffer));
} else{
assert(prefix_type == HashtableTextDump::StringPrefix, "Sanity");
ExceptionMark em(current);
JavaThread* THREAD = current; // For exception macros.
oop str = StringTable::intern(utf8_buffer, THREAD);
if (HAS_PENDING_EXCEPTION) {
log_warning(cds, heap)("[line %d] extra interned string allocation failed; size too large: %d",
reader.last_line_no(), utf8_length);
CLEAR_PENDING_EXCEPTION;
} else {
#if INCLUDE_G1GC
if (UseG1GC) {
typeArrayOop body = java_lang_String::value(str);
const HeapRegion* hr = G1CollectedHeap::heap()->heap_region_containing(body);
if (hr->is_humongous()) {
// Don't keep it alive, so it will be GC'ed before we dump the strings, in order
// to maximize free heap space and minimize fragmentation.
log_warning(cds, heap)("[line %d] extra interned string ignored; size too large: %d",
reader.last_line_no(), utf8_length);
continue;
}
}
#endif
// Make sure this string is included in the dumped interned string table.
assert(str != NULL, "must succeed");
_extra_interned_strings->append(OopHandle(Universe::vm_global(), str));
}
}
}
}
// Read/write a data stream for restoring/preserving metadata pointers and
// miscellaneous data from/to the shared archive file.
void MetaspaceShared::serialize(SerializeClosure* soc) {
int tag = 0;
soc->do_tag(--tag);
// Verify the sizes of various metadata in the system.
soc->do_tag(sizeof(Method));
soc->do_tag(sizeof(ConstMethod));
soc->do_tag(arrayOopDesc::base_offset_in_bytes(T_BYTE));
soc->do_tag(sizeof(ConstantPool));
soc->do_tag(sizeof(ConstantPoolCache));
soc->do_tag(objArrayOopDesc::base_offset_in_bytes());
soc->do_tag(typeArrayOopDesc::base_offset_in_bytes(T_BYTE));
soc->do_tag(sizeof(Symbol));
// Need to do this first, as subsequent steps may call virtual functions
// in archived Metadata objects.
CppVtables::serialize(soc);
soc->do_tag(--tag);
// Dump/restore miscellaneous metadata.
JavaClasses::serialize_offsets(soc);
HeapShared::serialize_root(soc);
Universe::serialize(soc);
soc->do_tag(--tag);
// Dump/restore references to commonly used names and signatures.
vmSymbols::serialize(soc);
soc->do_tag(--tag);
// Dump/restore the symbol/string/subgraph_info tables
SymbolTable::serialize_shared_table_header(soc);
StringTable::serialize_shared_table_header(soc);
HeapShared::serialize_tables(soc);
SystemDictionaryShared::serialize_dictionary_headers(soc);
InstanceMirrorKlass::serialize_offsets(soc);
// Dump/restore well known classes (pointers)
SystemDictionaryShared::serialize_vm_classes(soc);
soc->do_tag(--tag);
CDS_JAVA_HEAP_ONLY(ClassLoaderDataShared::serialize(soc);)
LambdaFormInvokers::serialize(soc);
soc->do_tag(666);
}
static void rewrite_nofast_bytecode(const methodHandle& method) {
BytecodeStream bcs(method);
while (!bcs.is_last_bytecode()) {
Bytecodes::Code opcode = bcs.next();
switch (opcode) {
case Bytecodes::_getfield: *bcs.bcp() = Bytecodes::_nofast_getfield; break;
case Bytecodes::_putfield: *bcs.bcp() = Bytecodes::_nofast_putfield; break;
case Bytecodes::_aload_0: *bcs.bcp() = Bytecodes::_nofast_aload_0; break;
case Bytecodes::_iload: {
if (!bcs.is_wide()) {
*bcs.bcp() = Bytecodes::_nofast_iload;
}
break;
}
default: break;
}
}
}
// [1] Rewrite all bytecodes as needed, so that the ConstMethod* will not be modified
// at run time by RewriteBytecodes/RewriteFrequentPairs
// [2] Assign a fingerprint, so one doesn't need to be assigned at run-time.
void MetaspaceShared::rewrite_nofast_bytecodes_and_calculate_fingerprints(Thread* thread, InstanceKlass* ik) {
for (int i = 0; i < ik->methods()->length(); i++) {
methodHandle m(thread, ik->methods()->at(i));
if (ik->can_be_verified_at_dumptime() && ik->is_linked()) {
rewrite_nofast_bytecode(m);
}
Fingerprinter fp(m);
// The side effect of this call sets method's fingerprint field.
fp.fingerprint();
}
}
class VM_PopulateDumpSharedSpace : public VM_GC_Operation {
private:
GrowableArray<MemRegion> *_closed_heap_regions;
GrowableArray<MemRegion> *_open_heap_regions;
GrowableArray<ArchiveHeapBitmapInfo> *_closed_heap_bitmaps;
GrowableArray<ArchiveHeapBitmapInfo> *_open_heap_bitmaps;
void dump_java_heap_objects(GrowableArray<Klass*>* klasses) NOT_CDS_JAVA_HEAP_RETURN;
void dump_heap_bitmaps() NOT_CDS_JAVA_HEAP_RETURN;
void dump_heap_bitmaps(GrowableArray<MemRegion>* regions,
GrowableArray<ArchiveHeapBitmapInfo>* bitmaps);
void dump_one_heap_bitmap(MemRegion region, GrowableArray<ArchiveHeapBitmapInfo>* bitmaps,
ResourceBitMap bitmap, bool is_oopmap);
void dump_shared_symbol_table(GrowableArray<Symbol*>* symbols) {
log_info(cds)("Dumping symbol table ...");
SymbolTable::write_to_archive(symbols);
}
char* dump_read_only_tables();
public:
VM_PopulateDumpSharedSpace() :
VM_GC_Operation(0 /* total collections, ignored */, GCCause::_archive_time_gc),
_closed_heap_regions(NULL),
_open_heap_regions(NULL),
_closed_heap_bitmaps(NULL),
_open_heap_bitmaps(NULL) {}
bool skip_operation() const { return false; }
VMOp_Type type() const { return VMOp_PopulateDumpSharedSpace; }
void doit(); // outline because gdb sucks
bool allow_nested_vm_operations() const { return true; }
}; // class VM_PopulateDumpSharedSpace
class StaticArchiveBuilder : public ArchiveBuilder {
public:
StaticArchiveBuilder() : ArchiveBuilder() {}
virtual void iterate_roots(MetaspaceClosure* it, bool is_relocating_pointers) {
FileMapInfo::metaspace_pointers_do(it, false);
SystemDictionaryShared::dumptime_classes_do(it);
Universe::metaspace_pointers_do(it);
vmSymbols::metaspace_pointers_do(it);
// The above code should find all the symbols that are referenced by the
// archived classes. We just need to add the extra symbols which
// may not be used by any of the archived classes -- these are usually
// symbols that we anticipate to be used at run time, so we can store
// them in the RO region, to be shared across multiple processes.
if (_extra_symbols != NULL) {
for (int i = 0; i < _extra_symbols->length(); i++) {
it->push(_extra_symbols->adr_at(i));
}
}
}
};
char* VM_PopulateDumpSharedSpace::dump_read_only_tables() {
ArchiveBuilder::OtherROAllocMark mark;
SystemDictionaryShared::write_to_archive();
// Write lambform lines into archive
LambdaFormInvokers::dump_static_archive_invokers();
// Write the other data to the output array.
DumpRegion* ro_region = ArchiveBuilder::current()->ro_region();
char* start = ro_region->top();
WriteClosure wc(ro_region);
MetaspaceShared::serialize(&wc);
// Write the bitmaps for patching the archive heap regions
dump_heap_bitmaps();
return start;
}
void VM_PopulateDumpSharedSpace::doit() {
HeapShared::run_full_gc_in_vm_thread();
DEBUG_ONLY(SystemDictionaryShared::NoClassLoadingMark nclm);
FileMapInfo::check_nonempty_dir_in_shared_path_table();
NOT_PRODUCT(SystemDictionary::verify();)
// Block concurrent class unloading from changing the _dumptime_table
MutexLocker ml(DumpTimeTable_lock, Mutex::_no_safepoint_check_flag);
SystemDictionaryShared::check_excluded_classes();
StaticArchiveBuilder builder;
builder.gather_source_objs();
builder.reserve_buffer();
char* cloned_vtables = CppVtables::dumptime_init(&builder);
builder.dump_rw_metadata();
builder.dump_ro_metadata();
builder.relocate_metaspaceobj_embedded_pointers();
// Dump supported java heap objects
dump_java_heap_objects(builder.klasses());
builder.relocate_roots();
dump_shared_symbol_table(builder.symbols());
builder.relocate_vm_classes();
log_info(cds)("Make classes shareable");
builder.make_klasses_shareable();
char* serialized_data = dump_read_only_tables();
SystemDictionaryShared::adjust_lambda_proxy_class_dictionary();
// The vtable clones contain addresses of the current process.
// We don't want to write these addresses into the archive.
CppVtables::zero_archived_vtables();
// relocate the data so that it can be mapped to MetaspaceShared::requested_base_address()
// without runtime relocation.
builder.relocate_to_requested();
// Write the archive file
const char* static_archive = Arguments::GetSharedArchivePath();
assert(static_archive != nullptr, "SharedArchiveFile not set?");
FileMapInfo* mapinfo = new FileMapInfo(static_archive, true);
mapinfo->populate_header(MetaspaceShared::core_region_alignment());
mapinfo->set_serialized_data(serialized_data);
mapinfo->set_cloned_vtables(cloned_vtables);
mapinfo->open_for_write();
builder.write_archive(mapinfo,
_closed_heap_regions,
_open_heap_regions,
_closed_heap_bitmaps,
_open_heap_bitmaps);
if (PrintSystemDictionaryAtExit) {
SystemDictionary::print();
}
if (AllowArchivingWithJavaAgent) {
warning("This archive was created with AllowArchivingWithJavaAgent. It should be used "
"for testing purposes only and should not be used in a production environment");
}
// There may be pending VM operations. We have changed some global states
// (such as vmClasses::_klasses) that may cause these VM operations
// to fail. For safety, forget these operations and exit the VM directly.
os::_exit(0);
}
class CollectCLDClosure : public CLDClosure {
GrowableArray<ClassLoaderData*> _loaded_cld;
GrowableArray<OopHandle> _loaded_cld_handles; // keep the CLDs alive
Thread* _current_thread;
public:
CollectCLDClosure(Thread* thread) : _current_thread(thread) {}
~CollectCLDClosure() {
for (int i = 0; i < _loaded_cld_handles.length(); i++) {
_loaded_cld_handles.at(i).release(Universe::vm_global());
}
}
void do_cld(ClassLoaderData* cld) {
assert(cld->is_alive(), "must be");
_loaded_cld.append(cld);
_loaded_cld_handles.append(OopHandle(Universe::vm_global(), cld->holder()));
}
int nof_cld() const { return _loaded_cld.length(); }
ClassLoaderData* cld_at(int index) { return _loaded_cld.at(index); }
};
// Check if we can eagerly link this class at dump time, so we can avoid the
// runtime linking overhead (especially verification)
bool MetaspaceShared::may_be_eagerly_linked(InstanceKlass* ik) {
if (!ik->can_be_verified_at_dumptime()) {
// For old classes, try to leave them in the unlinked state, so
// we can still store them in the archive. They must be
// linked/verified at runtime.
return false;
}
if (DynamicDumpSharedSpaces && ik->is_shared_unregistered_class()) {
// Linking of unregistered classes at this stage may cause more
// classes to be resolved, resulting in calls to ClassLoader.loadClass()
// that may not be expected by custom class loaders.
//
// It's OK to do this for the built-in loaders as we know they can
// tolerate this. (Note that unregistered classes are loaded by the NULL
// loader during DumpSharedSpaces).
return false;
}
return true;
}
bool MetaspaceShared::link_class_for_cds(InstanceKlass* ik, TRAPS) {
// Link the class to cause the bytecodes to be rewritten and the
// cpcache to be created. Class verification is done according
// to -Xverify setting.
bool res = MetaspaceShared::try_link_class(THREAD, ik);
ClassPrelinker::dumptime_resolve_constants(ik, CHECK_(false));
return res;
}
void MetaspaceShared::link_shared_classes(bool jcmd_request, TRAPS) {
ClassPrelinker::initialize();
if (!jcmd_request) {
LambdaFormInvokers::regenerate_holder_classes(CHECK);
}
// Collect all loaded ClassLoaderData.
CollectCLDClosure collect_cld(THREAD);
{
// ClassLoaderDataGraph::loaded_cld_do requires ClassLoaderDataGraph_lock.
// We cannot link the classes while holding this lock (or else we may run into deadlock).
// Therefore, we need to first collect all the CLDs, and then link their classes after
// releasing the lock.
MutexLocker lock(ClassLoaderDataGraph_lock);
ClassLoaderDataGraph::loaded_cld_do(&collect_cld);
}
while (true) {
bool has_linked = false;
for (int i = 0; i < collect_cld.nof_cld(); i++) {
ClassLoaderData* cld = collect_cld.cld_at(i);
for (Klass* klass = cld->klasses(); klass != NULL; klass = klass->next_link()) {
if (klass->is_instance_klass()) {
InstanceKlass* ik = InstanceKlass::cast(klass);
if (may_be_eagerly_linked(ik)) {
has_linked |= link_class_for_cds(ik, CHECK);
}
}
}
}
if (!has_linked) {
break;
}
// Class linking includes verification which may load more classes.
// Keep scanning until we have linked no more classes.
}
}
void MetaspaceShared::prepare_for_dumping() {
Arguments::assert_is_dumping_archive();
Arguments::check_unsupported_dumping_properties();
ClassLoader::initialize_shared_path(JavaThread::current());
}
// Preload classes from a list, populate the shared spaces and dump to a
// file.
void MetaspaceShared::preload_and_dump() {
EXCEPTION_MARK;
ResourceMark rm(THREAD);
preload_and_dump_impl(THREAD);
if (HAS_PENDING_EXCEPTION) {
if (PENDING_EXCEPTION->is_a(vmClasses::OutOfMemoryError_klass())) {
vm_direct_exit(-1, err_msg("Out of memory. Please run with a larger Java heap, current MaxHeapSize = "
SIZE_FORMAT "M", MaxHeapSize/M));
} else {
log_error(cds)("%s: %s", PENDING_EXCEPTION->klass()->external_name(),
java_lang_String::as_utf8_string(java_lang_Throwable::message(PENDING_EXCEPTION)));
vm_direct_exit(-1, "VM exits due to exception, use -Xlog:cds,exceptions=trace for detail");
}
} else {
// On success, the VM_PopulateDumpSharedSpace op should have
// exited the VM.
ShouldNotReachHere();
}
}
#if INCLUDE_CDS_JAVA_HEAP && defined(_LP64)
void MetaspaceShared::adjust_heap_sizes_for_dumping() {
if (!DumpSharedSpaces || UseCompressedOops) {
return;
}
// CDS heap dumping requires all string oops to have an offset
// from the heap bottom that can be encoded in 32-bit.
julong max_heap_size = (julong)(4 * G);
if (MinHeapSize > max_heap_size) {
log_debug(cds)("Setting MinHeapSize to 4G for CDS dumping, original size = " SIZE_FORMAT "M", MinHeapSize/M);
FLAG_SET_ERGO(MinHeapSize, max_heap_size);
}
if (InitialHeapSize > max_heap_size) {
log_debug(cds)("Setting InitialHeapSize to 4G for CDS dumping, original size = " SIZE_FORMAT "M", InitialHeapSize/M);
FLAG_SET_ERGO(InitialHeapSize, max_heap_size);
}
if (MaxHeapSize > max_heap_size) {
log_debug(cds)("Setting MaxHeapSize to 4G for CDS dumping, original size = " SIZE_FORMAT "M", MaxHeapSize/M);
FLAG_SET_ERGO(MaxHeapSize, max_heap_size);
}
}
#endif // INCLUDE_CDS_JAVA_HEAP && _LP64
void MetaspaceShared::get_default_classlist(char* default_classlist, const size_t buf_size) {
// Construct the path to the class list (in jre/lib)
// Walk up two directories from the location of the VM and
// optionally tack on "lib" (depending on platform)
os::jvm_path(default_classlist, (jint)(buf_size));
for (int i = 0; i < 3; i++) {
char *end = strrchr(default_classlist, *os::file_separator());
if (end != NULL) *end = '\0';
}
size_t classlist_path_len = strlen(default_classlist);
if (classlist_path_len >= 3) {
if (strcmp(default_classlist + classlist_path_len - 3, "lib") != 0) {
if (classlist_path_len < buf_size - 4) {
jio_snprintf(default_classlist + classlist_path_len,
buf_size - classlist_path_len,
"%slib", os::file_separator());
classlist_path_len += 4;
}
}
}
if (classlist_path_len < buf_size - 10) {
jio_snprintf(default_classlist + classlist_path_len,
buf_size - classlist_path_len,
"%sclasslist", os::file_separator());
}
}
void MetaspaceShared::preload_classes(TRAPS) {
char default_classlist[JVM_MAXPATHLEN];
const char* classlist_path;
get_default_classlist(default_classlist, sizeof(default_classlist));
if (SharedClassListFile == NULL) {
classlist_path = default_classlist;
} else {
classlist_path = SharedClassListFile;
}
log_info(cds)("Loading classes to share ...");
_has_error_classes = false;
int class_count = ClassListParser::parse_classlist(classlist_path,
ClassListParser::_parse_all, CHECK);
if (ExtraSharedClassListFile) {
class_count += ClassListParser::parse_classlist(ExtraSharedClassListFile,
ClassListParser::_parse_all, CHECK);
}
if (classlist_path != default_classlist) {
struct stat statbuf;
if (os::stat(default_classlist, &statbuf) == 0) {
// File exists, let's use it.
class_count += ClassListParser::parse_classlist(default_classlist,
ClassListParser::_parse_lambda_forms_invokers_only, CHECK);
}
}
// Exercise the manifest processing code to ensure classes used by CDS at runtime
// are always archived
const char* dummy = "Manifest-Version: 1.0\n";
CDSProtectionDomain::create_jar_manifest(dummy, strlen(dummy), CHECK);
log_info(cds)("Loading classes to share: done.");
log_info(cds)("Shared spaces: preloaded %d classes", class_count);
}
void MetaspaceShared::preload_and_dump_impl(TRAPS) {
preload_classes(CHECK);
if (SharedArchiveConfigFile) {
log_info(cds)("Reading extra data from %s ...", SharedArchiveConfigFile);
read_extra_data(THREAD, SharedArchiveConfigFile);
log_info(cds)("Reading extra data: done.");
}
HeapShared::init_for_dumping(CHECK);
// Rewrite and link classes
log_info(cds)("Rewriting and linking classes ...");
// Link any classes which got missed. This would happen if we have loaded classes that
// were not explicitly specified in the classlist. E.g., if an interface implemented by class K
// fails verification, all other interfaces that were not specified in the classlist but
// are implemented by K are not verified.
link_shared_classes(false/*not from jcmd*/, CHECK);
log_info(cds)("Rewriting and linking classes: done");
#if INCLUDE_CDS_JAVA_HEAP
if (use_full_module_graph()) {
HeapShared::reset_archived_object_states(CHECK);
}
#endif
VM_PopulateDumpSharedSpace op;
VMThread::execute(&op);
}
// Returns true if the class's status has changed.
bool MetaspaceShared::try_link_class(JavaThread* current, InstanceKlass* ik) {
ExceptionMark em(current);
JavaThread* THREAD = current; // For exception macros.
Arguments::assert_is_dumping_archive();
if (ik->is_loaded() && !ik->is_linked() && ik->can_be_verified_at_dumptime() &&
!SystemDictionaryShared::has_class_failed_verification(ik)) {
bool saved = BytecodeVerificationLocal;
if (ik->is_shared_unregistered_class() && ik->class_loader() == NULL) {
// The verification decision is based on BytecodeVerificationRemote
// for non-system classes. Since we are using the NULL classloader
// to load non-system classes for customized class loaders during dumping,
// we need to temporarily change BytecodeVerificationLocal to be the same as
// BytecodeVerificationRemote. Note this can cause the parent system
// classes also being verified. The extra overhead is acceptable during
// dumping.
BytecodeVerificationLocal = BytecodeVerificationRemote;
}
ik->link_class(THREAD);
if (HAS_PENDING_EXCEPTION) {
ResourceMark rm(THREAD);
log_warning(cds)("Preload Warning: Verification failed for %s",
ik->external_name());
CLEAR_PENDING_EXCEPTION;
SystemDictionaryShared::set_class_has_failed_verification(ik);
_has_error_classes = true;
}
BytecodeVerificationLocal = saved;
return true;
} else {
return false;
}
}
#if INCLUDE_CDS_JAVA_HEAP
void VM_PopulateDumpSharedSpace::dump_java_heap_objects(GrowableArray<Klass*>* klasses) {
if(!HeapShared::can_write()) {
log_info(cds)(
"Archived java heap is not supported as UseG1GC "
"and UseCompressedClassPointers are required."
"Current settings: UseG1GC=%s, UseCompressedClassPointers=%s.",
BOOL_TO_STR(UseG1GC), BOOL_TO_STR(UseCompressedClassPointers));
return;
}
// Find all the interned strings that should be dumped.
int i;
for (i = 0; i < klasses->length(); i++) {
Klass* k = klasses->at(i);
if (k->is_instance_klass()) {
InstanceKlass* ik = InstanceKlass::cast(k);
if (ik->is_linked()) {
ik->constants()->add_dumped_interned_strings();
}
}
}
if (_extra_interned_strings != NULL) {
for (i = 0; i < _extra_interned_strings->length(); i ++) {
OopHandle string = _extra_interned_strings->at(i);
HeapShared::add_to_dumped_interned_strings(string.resolve());
}
}
// The closed and open archive heap space has maximum two regions.
// See FileMapInfo::write_heap_regions() for details.
_closed_heap_regions = new GrowableArray<MemRegion>(2);
_open_heap_regions = new GrowableArray<MemRegion>(2);
HeapShared::archive_objects(_closed_heap_regions, _open_heap_regions);
ArchiveBuilder::OtherROAllocMark mark;
HeapShared::write_subgraph_info_table();
}
void VM_PopulateDumpSharedSpace::dump_heap_bitmaps() {
if (HeapShared::can_write()) {
_closed_heap_bitmaps = new GrowableArray<ArchiveHeapBitmapInfo>(2);
dump_heap_bitmaps(_closed_heap_regions, _closed_heap_bitmaps);
_open_heap_bitmaps = new GrowableArray<ArchiveHeapBitmapInfo>(2);
dump_heap_bitmaps(_open_heap_regions, _open_heap_bitmaps);
}
}
void VM_PopulateDumpSharedSpace::dump_heap_bitmaps(GrowableArray<MemRegion>* regions,
GrowableArray<ArchiveHeapBitmapInfo>* bitmaps) {
for (int i = 0; i < regions->length(); i++) {
MemRegion region = regions->at(i);
ResourceBitMap oopmap = HeapShared::calculate_oopmap(region);
ResourceBitMap ptrmap = HeapShared::calculate_ptrmap(region);
dump_one_heap_bitmap(region, bitmaps, oopmap, true);
dump_one_heap_bitmap(region, bitmaps, ptrmap, false);
}
}
void VM_PopulateDumpSharedSpace::dump_one_heap_bitmap(MemRegion region,
GrowableArray<ArchiveHeapBitmapInfo>* bitmaps,
ResourceBitMap bitmap, bool is_oopmap) {
size_t size_in_bits = bitmap.size();
size_t size_in_bytes;
uintptr_t* buffer;
if (size_in_bits > 0) {
size_in_bytes = bitmap.size_in_bytes();
buffer = (uintptr_t*)NEW_C_HEAP_ARRAY(char, size_in_bytes, mtInternal);
bitmap.write_to(buffer, size_in_bytes);
} else {
size_in_bytes = 0;
buffer = NULL;
}
log_info(cds, heap)("%s = " INTPTR_FORMAT " (" SIZE_FORMAT_W(6) " bytes) for heap region "
INTPTR_FORMAT " (" SIZE_FORMAT_W(8) " bytes)",
is_oopmap ? "Oopmap" : "Ptrmap",
p2i(buffer), size_in_bytes,
p2i(region.start()), region.byte_size());
ArchiveHeapBitmapInfo info;
info._map = (address)buffer;
info._size_in_bits = size_in_bits;
info._size_in_bytes = size_in_bytes;
bitmaps->append(info);
}
#endif // INCLUDE_CDS_JAVA_HEAP
void MetaspaceShared::set_shared_metaspace_range(void* base, void *static_top, void* top) {
assert(base <= static_top && static_top <= top, "must be");
_shared_metaspace_static_top = static_top;
MetaspaceObj::set_shared_metaspace_range(base, top);
}
bool MetaspaceShared::is_shared_dynamic(void* p) {
if ((p < MetaspaceObj::shared_metaspace_top()) &&
(p >= _shared_metaspace_static_top)) {
return true;
} else {
return false;
}
}
void MetaspaceShared::initialize_runtime_shared_and_meta_spaces() {
assert(UseSharedSpaces, "Must be called when UseSharedSpaces is enabled");
MapArchiveResult result = MAP_ARCHIVE_OTHER_FAILURE;
FileMapInfo* static_mapinfo = open_static_archive();
FileMapInfo* dynamic_mapinfo = NULL;
if (static_mapinfo != NULL) {
log_info(cds)("Core region alignment: " SIZE_FORMAT, static_mapinfo->core_region_alignment());
dynamic_mapinfo = open_dynamic_archive();
// First try to map at the requested address
result = map_archives(static_mapinfo, dynamic_mapinfo, true);
if (result == MAP_ARCHIVE_MMAP_FAILURE) {
// Mapping has failed (probably due to ASLR). Let's map at an address chosen
// by the OS.
log_info(cds)("Try to map archive(s) at an alternative address");
result = map_archives(static_mapinfo, dynamic_mapinfo, false);
}
}
if (result == MAP_ARCHIVE_SUCCESS) {
bool dynamic_mapped = (dynamic_mapinfo != NULL && dynamic_mapinfo->is_mapped());
char* cds_base = static_mapinfo->mapped_base();
char* cds_end = dynamic_mapped ? dynamic_mapinfo->mapped_end() : static_mapinfo->mapped_end();
set_shared_metaspace_range(cds_base, static_mapinfo->mapped_end(), cds_end);
_relocation_delta = static_mapinfo->relocation_delta();
_requested_base_address = static_mapinfo->requested_base_address();
if (dynamic_mapped) {
FileMapInfo::set_shared_path_table(dynamic_mapinfo);
// turn AutoCreateSharedArchive off if successfully mapped
AutoCreateSharedArchive = false;
} else {
FileMapInfo::set_shared_path_table(static_mapinfo);
}
} else {
set_shared_metaspace_range(NULL, NULL, NULL);
if (DynamicDumpSharedSpaces) {
warning("-XX:ArchiveClassesAtExit is unsupported when base CDS archive is not loaded. Run with -Xlog:cds for more info.");
}
UseSharedSpaces = false;
// The base archive cannot be mapped. We cannot dump the dynamic shared archive.
AutoCreateSharedArchive = false;
DynamicDumpSharedSpaces = false;
FileMapInfo::fail_continue("Unable to map shared spaces");
if (PrintSharedArchiveAndExit) {
vm_exit_during_initialization("Unable to use shared archive.");
}
}
if (static_mapinfo != NULL && !static_mapinfo->is_mapped()) {
delete static_mapinfo;
}
if (dynamic_mapinfo != NULL && !dynamic_mapinfo->is_mapped()) {
delete dynamic_mapinfo;
}
}
FileMapInfo* MetaspaceShared::open_static_archive() {
const char* static_archive = Arguments::GetSharedArchivePath();
assert(static_archive != nullptr, "SharedArchivePath is NULL");
FileMapInfo* mapinfo = new FileMapInfo(static_archive, true);
if (!mapinfo->initialize()) {
delete(mapinfo);
return NULL;
}
return mapinfo;
}
FileMapInfo* MetaspaceShared::open_dynamic_archive() {
if (DynamicDumpSharedSpaces) {
return NULL;
}
const char* dynamic_archive = Arguments::GetSharedDynamicArchivePath();
if (dynamic_archive == nullptr) {
return NULL;
}
FileMapInfo* mapinfo = new FileMapInfo(dynamic_archive, false);
if (!mapinfo->initialize()) {
delete(mapinfo);
return NULL;
}
return mapinfo;
}
// use_requested_addr:
// true = map at FileMapHeader::_requested_base_address
// false = map at an alternative address picked by OS.
MapArchiveResult MetaspaceShared::map_archives(FileMapInfo* static_mapinfo, FileMapInfo* dynamic_mapinfo,
bool use_requested_addr) {
if (use_requested_addr && static_mapinfo->requested_base_address() == NULL) {
log_info(cds)("Archive(s) were created with -XX:SharedBaseAddress=0. Always map at os-selected address.");
return MAP_ARCHIVE_MMAP_FAILURE;
}
PRODUCT_ONLY(if (ArchiveRelocationMode == 1 && use_requested_addr) {
// For product build only -- this is for benchmarking the cost of doing relocation.
// For debug builds, the check is done below, after reserving the space, for better test coverage
// (see comment below).
log_info(cds)("ArchiveRelocationMode == 1: always map archive(s) at an alternative address");
return MAP_ARCHIVE_MMAP_FAILURE;
});
if (ArchiveRelocationMode == 2 && !use_requested_addr) {
log_info(cds)("ArchiveRelocationMode == 2: never map archive(s) at an alternative address");
return MAP_ARCHIVE_MMAP_FAILURE;
};
if (dynamic_mapinfo != NULL) {
// Ensure that the OS won't be able to allocate new memory spaces between the two
// archives, or else it would mess up the simple comparison in MetaspaceObj::is_shared().
assert(static_mapinfo->mapping_end_offset() == dynamic_mapinfo->mapping_base_offset(), "no gap");
}
ReservedSpace total_space_rs, archive_space_rs, class_space_rs;
MapArchiveResult result = MAP_ARCHIVE_OTHER_FAILURE;
char* mapped_base_address = reserve_address_space_for_archives(static_mapinfo,
dynamic_mapinfo,
use_requested_addr,
total_space_rs,
archive_space_rs,
class_space_rs);
if (mapped_base_address == NULL) {
result = MAP_ARCHIVE_MMAP_FAILURE;
log_debug(cds)("Failed to reserve spaces (use_requested_addr=%u)", (unsigned)use_requested_addr);
} else {
#ifdef ASSERT
// Some sanity checks after reserving address spaces for archives
// and class space.
assert(archive_space_rs.is_reserved(), "Sanity");
if (Metaspace::using_class_space()) {
// Class space must closely follow the archive space. Both spaces
// must be aligned correctly.
assert(class_space_rs.is_reserved(),
"A class space should have been reserved");
assert(class_space_rs.base() >= archive_space_rs.end(),
"class space should follow the cds archive space");
assert(is_aligned(archive_space_rs.base(),
core_region_alignment()),
"Archive space misaligned");
assert(is_aligned(class_space_rs.base(),
Metaspace::reserve_alignment()),
"class space misaligned");
}
#endif // ASSERT
log_info(cds)("Reserved archive_space_rs [" INTPTR_FORMAT " - " INTPTR_FORMAT "] (" SIZE_FORMAT ") bytes",
p2i(archive_space_rs.base()), p2i(archive_space_rs.end()), archive_space_rs.size());
log_info(cds)("Reserved class_space_rs [" INTPTR_FORMAT " - " INTPTR_FORMAT "] (" SIZE_FORMAT ") bytes",
p2i(class_space_rs.base()), p2i(class_space_rs.end()), class_space_rs.size());
if (MetaspaceShared::use_windows_memory_mapping()) {
// We have now reserved address space for the archives, and will map in
// the archive files into this space.
//
// Special handling for Windows: on Windows we cannot map a file view
// into an existing memory mapping. So, we unmap the address range we
// just reserved again, which will make it available for mapping the
// archives.
// Reserving this range has not been for naught however since it makes
// us reasonably sure the address range is available.
//
// But still it may fail, since between unmapping the range and mapping
// in the archive someone else may grab the address space. Therefore
// there is a fallback in FileMap::map_region() where we just read in
// the archive files sequentially instead of mapping it in. We couple
// this with use_requested_addr, since we're going to patch all the
// pointers anyway so there's no benefit to mmap.
if (use_requested_addr) {
assert(!total_space_rs.is_reserved(), "Should not be reserved for Windows");
log_info(cds)("Windows mmap workaround: releasing archive space.");
archive_space_rs.release();
}
}
MapArchiveResult static_result = map_archive(static_mapinfo, mapped_base_address, archive_space_rs);
MapArchiveResult dynamic_result = (static_result == MAP_ARCHIVE_SUCCESS) ?
map_archive(dynamic_mapinfo, mapped_base_address, archive_space_rs) : MAP_ARCHIVE_OTHER_FAILURE;
DEBUG_ONLY(if (ArchiveRelocationMode == 1 && use_requested_addr) {
// This is for simulating mmap failures at the requested address. In
// debug builds, we do it here (after all archives have possibly been
// mapped), so we can thoroughly test the code for failure handling
// (releasing all allocated resource, etc).
log_info(cds)("ArchiveRelocationMode == 1: always map archive(s) at an alternative address");
if (static_result == MAP_ARCHIVE_SUCCESS) {
static_result = MAP_ARCHIVE_MMAP_FAILURE;
}
if (dynamic_result == MAP_ARCHIVE_SUCCESS) {
dynamic_result = MAP_ARCHIVE_MMAP_FAILURE;
}
});
if (static_result == MAP_ARCHIVE_SUCCESS) {
if (dynamic_result == MAP_ARCHIVE_SUCCESS) {
result = MAP_ARCHIVE_SUCCESS;
} else if (dynamic_result == MAP_ARCHIVE_OTHER_FAILURE) {
assert(dynamic_mapinfo != NULL && !dynamic_mapinfo->is_mapped(), "must have failed");
// No need to retry mapping the dynamic archive again, as it will never succeed
// (bad file, etc) -- just keep the base archive.
log_warning(cds, dynamic)("Unable to use shared archive. The top archive failed to load: %s",
dynamic_mapinfo->full_path());
result = MAP_ARCHIVE_SUCCESS;
// TODO, we can give the unused space for the dynamic archive to class_space_rs, but there's no
// easy API to do that right now.
} else {
result = MAP_ARCHIVE_MMAP_FAILURE;
}
} else if (static_result == MAP_ARCHIVE_OTHER_FAILURE) {
result = MAP_ARCHIVE_OTHER_FAILURE;
} else {
result = MAP_ARCHIVE_MMAP_FAILURE;
}
}
if (result == MAP_ARCHIVE_SUCCESS) {
SharedBaseAddress = (size_t)mapped_base_address;
LP64_ONLY({
if (Metaspace::using_class_space()) {
// Set up ccs in metaspace.
Metaspace::initialize_class_space(class_space_rs);
// Set up compressed Klass pointer encoding: the encoding range must
// cover both archive and class space.
address cds_base = (address)static_mapinfo->mapped_base();
address ccs_end = (address)class_space_rs.end();
assert(ccs_end > cds_base, "Sanity check");
CompressedKlassPointers::initialize(cds_base, ccs_end - cds_base);
// map_heap_regions() compares the current narrow oop and klass encodings
// with the archived ones, so it must be done after all encodings are determined.
static_mapinfo->map_or_load_heap_regions();
}
});
log_info(cds)("optimized module handling: %s", MetaspaceShared::use_optimized_module_handling() ? "enabled" : "disabled");
log_info(cds)("full module graph: %s", MetaspaceShared::use_full_module_graph() ? "enabled" : "disabled");
} else {
unmap_archive(static_mapinfo);
unmap_archive(dynamic_mapinfo);
release_reserved_spaces(total_space_rs, archive_space_rs, class_space_rs);
}
return result;
}
// This will reserve two address spaces suitable to house Klass structures, one
// for the cds archives (static archive and optionally dynamic archive) and
// optionally one move for ccs.
//
// Since both spaces must fall within the compressed class pointer encoding
// range, they are allocated close to each other.
//
// Space for archives will be reserved first, followed by a potential gap,
// followed by the space for ccs:
//
// +-- Base address A B End
// | | | |
// v v v v
// +-------------+--------------+ +----------------------+
// | static arc | [dyn. arch] | [gap] | compr. class space |
// +-------------+--------------+ +----------------------+
//
// (The gap may result from different alignment requirements between metaspace
// and CDS)
//
// If UseCompressedClassPointers is disabled, only one address space will be
// reserved:
//
// +-- Base address End
// | |
// v v
// +-------------+--------------+
// | static arc | [dyn. arch] |
// +-------------+--------------+
//
// Base address: If use_archive_base_addr address is true, the Base address is
// determined by the address stored in the static archive. If
// use_archive_base_addr address is false, this base address is determined
// by the platform.
//
// If UseCompressedClassPointers=1, the range encompassing both spaces will be
// suitable to en/decode narrow Klass pointers: the base will be valid for
// encoding, the range [Base, End) not surpass KlassEncodingMetaspaceMax.
//
// Return:
//
// - On success:
// - total_space_rs will be reserved as whole for archive_space_rs and
// class_space_rs if UseCompressedClassPointers is true.
// On Windows, try reserve archive_space_rs and class_space_rs
// separately first if use_archive_base_addr is true.
// - archive_space_rs will be reserved and large enough to host static and
// if needed dynamic archive: [Base, A).
// archive_space_rs.base and size will be aligned to CDS reserve
// granularity.
// - class_space_rs: If UseCompressedClassPointers=1, class_space_rs will
// be reserved. Its start address will be aligned to metaspace reserve
// alignment, which may differ from CDS alignment. It will follow the cds
// archive space, close enough such that narrow class pointer encoding
// covers both spaces.
// If UseCompressedClassPointers=0, class_space_rs remains unreserved.
// - On error: NULL is returned and the spaces remain unreserved.
char* MetaspaceShared::reserve_address_space_for_archives(FileMapInfo* static_mapinfo,
FileMapInfo* dynamic_mapinfo,
bool use_archive_base_addr,
ReservedSpace& total_space_rs,
ReservedSpace& archive_space_rs,
ReservedSpace& class_space_rs) {
address const base_address = (address) (use_archive_base_addr ? static_mapinfo->requested_base_address() : NULL);
const size_t archive_space_alignment = core_region_alignment();
// Size and requested location of the archive_space_rs (for both static and dynamic archives)
assert(static_mapinfo->mapping_base_offset() == 0, "Must be");
size_t archive_end_offset = (dynamic_mapinfo == NULL) ? static_mapinfo->mapping_end_offset() : dynamic_mapinfo->mapping_end_offset();
size_t archive_space_size = align_up(archive_end_offset, archive_space_alignment);
// If a base address is given, it must have valid alignment and be suitable as encoding base.
if (base_address != NULL) {
assert(is_aligned(base_address, archive_space_alignment),
"Archive base address invalid: " PTR_FORMAT ".", p2i(base_address));
if (Metaspace::using_class_space()) {
assert(CompressedKlassPointers::is_valid_base(base_address),
"Archive base address invalid: " PTR_FORMAT ".", p2i(base_address));
}
}
if (!Metaspace::using_class_space()) {
// Get the simple case out of the way first:
// no compressed class space, simple allocation.
archive_space_rs = ReservedSpace(archive_space_size, archive_space_alignment,
os::vm_page_size(), (char*)base_address);
if (archive_space_rs.is_reserved()) {
assert(base_address == NULL ||
(address)archive_space_rs.base() == base_address, "Sanity");
// Register archive space with NMT.
MemTracker::record_virtual_memory_type(archive_space_rs.base(), mtClassShared);
return archive_space_rs.base();
}
return NULL;
}
#ifdef _LP64
// Complex case: two spaces adjacent to each other, both to be addressable
// with narrow class pointers.
// We reserve the whole range spanning both spaces, then split that range up.
const size_t class_space_alignment = Metaspace::reserve_alignment();
// To simplify matters, lets assume that metaspace alignment will always be
// equal or a multiple of archive alignment.
assert(is_power_of_2(class_space_alignment) &&
is_power_of_2(archive_space_alignment) &&
class_space_alignment >= archive_space_alignment,
"Sanity");
const size_t class_space_size = CompressedClassSpaceSize;
assert(CompressedClassSpaceSize > 0 &&
is_aligned(CompressedClassSpaceSize, class_space_alignment),
"CompressedClassSpaceSize malformed: "
SIZE_FORMAT, CompressedClassSpaceSize);
const size_t ccs_begin_offset = align_up(base_address + archive_space_size,
class_space_alignment) - base_address;
const size_t gap_size = ccs_begin_offset - archive_space_size;
const size_t total_range_size =
align_up(archive_space_size + gap_size + class_space_size, core_region_alignment());
assert(total_range_size > ccs_begin_offset, "must be");
if (use_windows_memory_mapping() && use_archive_base_addr) {
if (base_address != nullptr) {
// On Windows, we cannot safely split a reserved memory space into two (see JDK-8255917).
// Hence, we optimistically reserve archive space and class space side-by-side. We only
// do this for use_archive_base_addr=true since for use_archive_base_addr=false case
// caller will not split the combined space for mapping, instead read the archive data
// via sequential file IO.
address ccs_base = base_address + archive_space_size + gap_size;
archive_space_rs = ReservedSpace(archive_space_size, archive_space_alignment,
os::vm_page_size(), (char*)base_address);
class_space_rs = ReservedSpace(class_space_size, class_space_alignment,
os::vm_page_size(), (char*)ccs_base);
}
if (!archive_space_rs.is_reserved() || !class_space_rs.is_reserved()) {
release_reserved_spaces(total_space_rs, archive_space_rs, class_space_rs);
return NULL;
}
} else {
if (use_archive_base_addr && base_address != nullptr) {
total_space_rs = ReservedSpace(total_range_size, archive_space_alignment,
os::vm_page_size(), (char*) base_address);
} else {
// Reserve at any address, but leave it up to the platform to choose a good one.
total_space_rs = Metaspace::reserve_address_space_for_compressed_classes(total_range_size);
}
if (!total_space_rs.is_reserved()) {
return NULL;
}
// Paranoid checks:
assert(base_address == NULL || (address)total_space_rs.base() == base_address,
"Sanity (" PTR_FORMAT " vs " PTR_FORMAT ")", p2i(base_address), p2i(total_space_rs.base()));
assert(is_aligned(total_space_rs.base(), archive_space_alignment), "Sanity");
assert(total_space_rs.size() == total_range_size, "Sanity");
assert(CompressedKlassPointers::is_valid_base((address)total_space_rs.base()), "Sanity");
// Now split up the space into ccs and cds archive. For simplicity, just leave
// the gap reserved at the end of the archive space. Do not do real splitting.
archive_space_rs = total_space_rs.first_part(ccs_begin_offset,
(size_t)archive_space_alignment);
class_space_rs = total_space_rs.last_part(ccs_begin_offset);
MemTracker::record_virtual_memory_split_reserved(total_space_rs.base(), total_space_rs.size(),
ccs_begin_offset);
}
assert(is_aligned(archive_space_rs.base(), archive_space_alignment), "Sanity");
assert(is_aligned(archive_space_rs.size(), archive_space_alignment), "Sanity");
assert(is_aligned(class_space_rs.base(), class_space_alignment), "Sanity");
assert(is_aligned(class_space_rs.size(), class_space_alignment), "Sanity");
// NMT: fix up the space tags
MemTracker::record_virtual_memory_type(archive_space_rs.base(), mtClassShared);
MemTracker::record_virtual_memory_type(class_space_rs.base(), mtClass);
return archive_space_rs.base();
#else
ShouldNotReachHere();
return NULL;
#endif
}
void MetaspaceShared::release_reserved_spaces(ReservedSpace& total_space_rs,
ReservedSpace& archive_space_rs,
ReservedSpace& class_space_rs) {
if (total_space_rs.is_reserved()) {
log_debug(cds)("Released shared space (archive + class) " INTPTR_FORMAT, p2i(total_space_rs.base()));
total_space_rs.release();
} else {
if (archive_space_rs.is_reserved()) {
log_debug(cds)("Released shared space (archive) " INTPTR_FORMAT, p2i(archive_space_rs.base()));
archive_space_rs.release();
}
if (class_space_rs.is_reserved()) {
log_debug(cds)("Released shared space (classes) " INTPTR_FORMAT, p2i(class_space_rs.base()));
class_space_rs.release();
}
}
}
static int archive_regions[] = { MetaspaceShared::rw, MetaspaceShared::ro };
static int archive_regions_count = 2;
MapArchiveResult MetaspaceShared::map_archive(FileMapInfo* mapinfo, char* mapped_base_address, ReservedSpace rs) {
assert(UseSharedSpaces, "must be runtime");
if (mapinfo == NULL) {
return MAP_ARCHIVE_SUCCESS; // The dynamic archive has not been specified. No error has happened -- trivially succeeded.
}
mapinfo->set_is_mapped(false);
if (mapinfo->core_region_alignment() != (size_t)core_region_alignment()) {
log_info(cds)("Unable to map CDS archive -- core_region_alignment() expected: " SIZE_FORMAT
" actual: " SIZE_FORMAT, mapinfo->core_region_alignment(), core_region_alignment());
return MAP_ARCHIVE_OTHER_FAILURE;
}
MapArchiveResult result =
mapinfo->map_regions(archive_regions, archive_regions_count, mapped_base_address, rs);
if (result != MAP_ARCHIVE_SUCCESS) {
unmap_archive(mapinfo);
return result;
}
if (!mapinfo->validate_shared_path_table()) {
unmap_archive(mapinfo);
return MAP_ARCHIVE_OTHER_FAILURE;
}
mapinfo->set_is_mapped(true);
return MAP_ARCHIVE_SUCCESS;
}
void MetaspaceShared::unmap_archive(FileMapInfo* mapinfo) {
assert(UseSharedSpaces, "must be runtime");
if (mapinfo != NULL) {
mapinfo->unmap_regions(archive_regions, archive_regions_count);
mapinfo->unmap_region(MetaspaceShared::bm);
mapinfo->set_is_mapped(false);
}
}
// For -XX:PrintSharedArchiveAndExit
class CountSharedSymbols : public SymbolClosure {
private:
int _count;
public:
CountSharedSymbols() : _count(0) {}
void do_symbol(Symbol** sym) {
_count++;
}
int total() { return _count; }
};
// Read the miscellaneous data from the shared file, and
// serialize it out to its various destinations.
void MetaspaceShared::initialize_shared_spaces() {
FileMapInfo *static_mapinfo = FileMapInfo::current_info();
// Verify various attributes of the archive, plus initialize the
// shared string/symbol tables.
char* buffer = static_mapinfo->serialized_data();
intptr_t* array = (intptr_t*)buffer;
ReadClosure rc(&array);
serialize(&rc);
// Initialize the run-time symbol table.
SymbolTable::create_table();
// Finish up archived heap initialization. These must be
// done after ReadClosure.
static_mapinfo->patch_heap_embedded_pointers();
ArchiveHeapLoader::finish_initialization();
CDS_JAVA_HEAP_ONLY(Universe::update_archived_basic_type_mirrors());
// Close the mapinfo file
static_mapinfo->close();
static_mapinfo->unmap_region(MetaspaceShared::bm);
FileMapInfo *dynamic_mapinfo = FileMapInfo::dynamic_info();
if (dynamic_mapinfo != NULL) {
intptr_t* buffer = (intptr_t*)dynamic_mapinfo->serialized_data();
ReadClosure rc(&buffer);
SymbolTable::serialize_shared_table_header(&rc, false);
SystemDictionaryShared::serialize_dictionary_headers(&rc, false);
dynamic_mapinfo->close();
dynamic_mapinfo->unmap_region(MetaspaceShared::bm);
}
// Set up LambdaFormInvokers::_lambdaform_lines for dynamic dump
if (DynamicDumpSharedSpaces) {
// Read stored LF format lines stored in static archive
LambdaFormInvokers::read_static_archive_invokers();
}
if (PrintSharedArchiveAndExit) {
// Print archive names
if (dynamic_mapinfo != nullptr) {
tty->print_cr("\n\nBase archive name: %s", Arguments::GetSharedArchivePath());
tty->print_cr("Base archive version %d", static_mapinfo->version());
} else {
tty->print_cr("Static archive name: %s", static_mapinfo->full_path());
tty->print_cr("Static archive version %d", static_mapinfo->version());
}
SystemDictionaryShared::print_shared_archive(tty);
if (dynamic_mapinfo != nullptr) {
tty->print_cr("\n\nDynamic archive name: %s", dynamic_mapinfo->full_path());
tty->print_cr("Dynamic archive version %d", dynamic_mapinfo->version());
SystemDictionaryShared::print_shared_archive(tty, false/*dynamic*/);
}
// collect shared symbols and strings
CountSharedSymbols cl;
SymbolTable::shared_symbols_do(&cl);
tty->print_cr("Number of shared symbols: %d", cl.total());
tty->print_cr("Number of shared strings: %zu", StringTable::shared_entry_count());
tty->print_cr("VM version: %s\r\n", static_mapinfo->vm_version());
if (FileMapInfo::current_info() == NULL || _archive_loading_failed) {
tty->print_cr("archive is invalid");
vm_exit(1);
} else {
tty->print_cr("archive is valid");
vm_exit(0);
}
}
}
// JVM/TI RedefineClasses() support:
bool MetaspaceShared::remap_shared_readonly_as_readwrite() {
assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint");
if (UseSharedSpaces) {
// remap the shared readonly space to shared readwrite, private
FileMapInfo* mapinfo = FileMapInfo::current_info();
if (!mapinfo->remap_shared_readonly_as_readwrite()) {
return false;
}
if (FileMapInfo::dynamic_info() != NULL) {
mapinfo = FileMapInfo::dynamic_info();
if (!mapinfo->remap_shared_readonly_as_readwrite()) {
return false;
}
}
_remapped_readwrite = true;
}
return true;
}
bool MetaspaceShared::use_full_module_graph() {
#if INCLUDE_CDS_JAVA_HEAP
if (ClassLoaderDataShared::is_full_module_graph_loaded()) {
return true;
}
#endif
bool result = _use_optimized_module_handling && _use_full_module_graph;
if (DumpSharedSpaces) {
result &= HeapShared::can_write();
} else if (UseSharedSpaces) {
result &= ArchiveHeapLoader::can_use();
} else {
result = false;
}
if (result && UseSharedSpaces) {
// Classes used by the archived full module graph are loaded in JVMTI early phase.
assert(!(JvmtiExport::should_post_class_file_load_hook() && JvmtiExport::has_early_class_hook_env()),
"CDS should be disabled if early class hooks are enabled");
}
return result;
}
void MetaspaceShared::print_on(outputStream* st) {
if (UseSharedSpaces) {
st->print("CDS archive(s) mapped at: ");
address base = (address)MetaspaceObj::shared_metaspace_base();
address static_top = (address)_shared_metaspace_static_top;
address top = (address)MetaspaceObj::shared_metaspace_top();
st->print("[" PTR_FORMAT "-" PTR_FORMAT "-" PTR_FORMAT "), ", p2i(base), p2i(static_top), p2i(top));
st->print("size " SIZE_FORMAT ", ", top - base);
st->print("SharedBaseAddress: " PTR_FORMAT ", ArchiveRelocationMode: %d.", SharedBaseAddress, ArchiveRelocationMode);
} else {
st->print("CDS archive(s) not mapped");
}
st->cr();
}
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