| /* |
| * Copyright (c) 1997, 2018, 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/altHashing.hpp" |
| #include "classfile/compactHashtable.hpp" |
| #include "classfile/javaClasses.inline.hpp" |
| #include "classfile/stringTable.hpp" |
| #include "classfile/systemDictionary.hpp" |
| #include "gc/shared/collectedHeap.hpp" |
| #include "gc/shared/oopStorage.inline.hpp" |
| #include "gc/shared/oopStorageParState.inline.hpp" |
| #include "logging/log.hpp" |
| #include "logging/logStream.hpp" |
| #include "memory/allocation.inline.hpp" |
| #include "memory/filemap.hpp" |
| #include "memory/heapShared.inline.hpp" |
| #include "memory/metaspaceShared.inline.hpp" |
| #include "memory/resourceArea.hpp" |
| #include "memory/universe.hpp" |
| #include "oops/access.inline.hpp" |
| #include "oops/oop.inline.hpp" |
| #include "oops/typeArrayOop.inline.hpp" |
| #include "oops/weakHandle.inline.hpp" |
| #include "runtime/atomic.hpp" |
| #include "runtime/handles.inline.hpp" |
| #include "runtime/mutexLocker.hpp" |
| #include "runtime/safepointVerifiers.hpp" |
| #include "runtime/timerTrace.hpp" |
| #include "runtime/interfaceSupport.inline.hpp" |
| #include "services/diagnosticCommand.hpp" |
| #include "utilities/concurrentHashTable.inline.hpp" |
| #include "utilities/concurrentHashTableTasks.inline.hpp" |
| #include "utilities/macros.hpp" |
| |
| // We prefer short chains of avg 2 |
| #define PREF_AVG_LIST_LEN 2 |
| // 2^24 is max size |
| #define END_SIZE 24 |
| // If a chain gets to 32 something might be wrong |
| #define REHASH_LEN 32 |
| // If we have as many dead items as 50% of the number of bucket |
| #define CLEAN_DEAD_HIGH_WATER_MARK 0.5 |
| |
| #if INCLUDE_CDS_JAVA_HEAP |
| inline oop read_string_from_compact_hashtable(address base_address, u4 offset) { |
| assert(sizeof(narrowOop) == sizeof(offset), "must be"); |
| narrowOop v = (narrowOop)offset; |
| return HeapShared::decode_from_archive(v); |
| } |
| |
| static CompactHashtable< |
| const jchar*, oop, |
| read_string_from_compact_hashtable, |
| java_lang_String::equals |
| > _shared_table; |
| #endif |
| |
| // -------------------------------------------------------------------------- |
| StringTable* StringTable::_the_table = NULL; |
| volatile bool StringTable::_shared_string_mapped = false; |
| volatile bool StringTable::_alt_hash = false; |
| |
| static juint murmur_seed = 0; |
| |
| uintx hash_string(const jchar* s, int len, bool useAlt) { |
| return useAlt ? |
| AltHashing::murmur3_32(murmur_seed, s, len) : |
| java_lang_String::hash_code(s, len); |
| } |
| |
| class StringTableConfig : public StringTableHash::BaseConfig { |
| private: |
| public: |
| static uintx get_hash(WeakHandle<vm_string_table_data> const& value, |
| bool* is_dead) { |
| EXCEPTION_MARK; |
| oop val_oop = value.peek(); |
| if (val_oop == NULL) { |
| *is_dead = true; |
| return 0; |
| } |
| *is_dead = false; |
| ResourceMark rm(THREAD); |
| // All String oops are hashed as unicode |
| int length; |
| jchar* chars = java_lang_String::as_unicode_string(val_oop, length, THREAD); |
| if (chars != NULL) { |
| return hash_string(chars, length, StringTable::_alt_hash); |
| } |
| vm_exit_out_of_memory(length, OOM_MALLOC_ERROR, "get hash from oop"); |
| return 0; |
| } |
| // We use default allocation/deallocation but counted |
| static void* allocate_node(size_t size, |
| WeakHandle<vm_string_table_data> const& value) { |
| StringTable::item_added(); |
| return StringTableHash::BaseConfig::allocate_node(size, value); |
| } |
| static void free_node(void* memory, |
| WeakHandle<vm_string_table_data> const& value) { |
| value.release(); |
| StringTableHash::BaseConfig::free_node(memory, value); |
| StringTable::item_removed(); |
| } |
| }; |
| |
| class StringTableLookupJchar : StackObj { |
| private: |
| Thread* _thread; |
| uintx _hash; |
| int _len; |
| const jchar* _str; |
| Handle _found; |
| |
| public: |
| StringTableLookupJchar(Thread* thread, uintx hash, const jchar* key, int len) |
| : _thread(thread), _hash(hash), _len(len), _str(key) { |
| } |
| uintx get_hash() const { |
| return _hash; |
| } |
| bool equals(WeakHandle<vm_string_table_data>* value, bool* is_dead) { |
| oop val_oop = value->peek(); |
| if (val_oop == NULL) { |
| // dead oop, mark this hash dead for cleaning |
| *is_dead = true; |
| return false; |
| } |
| bool equals = java_lang_String::equals(val_oop, _str, _len); |
| if (!equals) { |
| return false; |
| } |
| // Need to resolve weak handle and Handleize through possible safepoint. |
| _found = Handle(_thread, value->resolve()); |
| return true; |
| } |
| }; |
| |
| class StringTableLookupOop : public StackObj { |
| private: |
| Thread* _thread; |
| uintx _hash; |
| Handle _find; |
| Handle _found; // Might be a different oop with the same value that's already |
| // in the table, which is the point. |
| public: |
| StringTableLookupOop(Thread* thread, uintx hash, Handle handle) |
| : _thread(thread), _hash(hash), _find(handle) { } |
| |
| uintx get_hash() const { |
| return _hash; |
| } |
| |
| bool equals(WeakHandle<vm_string_table_data>* value, bool* is_dead) { |
| oop val_oop = value->peek(); |
| if (val_oop == NULL) { |
| // dead oop, mark this hash dead for cleaning |
| *is_dead = true; |
| return false; |
| } |
| bool equals = java_lang_String::equals(_find(), val_oop); |
| if (!equals) { |
| return false; |
| } |
| // Need to resolve weak handle and Handleize through possible safepoint. |
| _found = Handle(_thread, value->resolve()); |
| return true; |
| } |
| }; |
| |
| static size_t ceil_log2(size_t val) { |
| size_t ret; |
| for (ret = 1; ((size_t)1 << ret) < val; ++ret); |
| return ret; |
| } |
| |
| StringTable::StringTable() : _local_table(NULL), _current_size(0), _has_work(0), |
| _needs_rehashing(false), _weak_handles(NULL), _items_count(0), _uncleaned_items_count(0) { |
| _weak_handles = new OopStorage("StringTable weak", |
| StringTableWeakAlloc_lock, |
| StringTableWeakActive_lock); |
| size_t start_size_log_2 = ceil_log2(StringTableSize); |
| _current_size = ((size_t)1) << start_size_log_2; |
| log_trace(stringtable)("Start size: " SIZE_FORMAT " (" SIZE_FORMAT ")", |
| _current_size, start_size_log_2); |
| _local_table = new StringTableHash(start_size_log_2, END_SIZE, REHASH_LEN); |
| } |
| |
| size_t StringTable::item_added() { |
| return Atomic::add((size_t)1, &(the_table()->_items_count)); |
| } |
| |
| size_t StringTable::add_items_count_to_clean(size_t ndead) { |
| size_t total = Atomic::add((size_t)ndead, &(the_table()->_uncleaned_items_count)); |
| log_trace(stringtable)( |
| "Uncleaned items:" SIZE_FORMAT " added: " SIZE_FORMAT " total:" SIZE_FORMAT, |
| the_table()->_uncleaned_items_count, ndead, total); |
| return total; |
| } |
| |
| void StringTable::item_removed() { |
| Atomic::add((size_t)-1, &(the_table()->_items_count)); |
| } |
| |
| double StringTable::get_load_factor() { |
| return (double)_items_count/_current_size; |
| } |
| |
| double StringTable::get_dead_factor() { |
| return (double)_uncleaned_items_count/_current_size; |
| } |
| |
| size_t StringTable::table_size() { |
| return ((size_t)1) << _local_table->get_size_log2(Thread::current()); |
| } |
| |
| void StringTable::trigger_concurrent_work() { |
| MutexLockerEx ml(Service_lock, Mutex::_no_safepoint_check_flag); |
| the_table()->_has_work = true; |
| Service_lock->notify_all(); |
| } |
| |
| // Probing |
| oop StringTable::lookup(Symbol* symbol) { |
| ResourceMark rm; |
| int length; |
| jchar* chars = symbol->as_unicode(length); |
| return lookup(chars, length); |
| } |
| |
| oop StringTable::lookup(const jchar* name, int len) { |
| unsigned int hash = java_lang_String::hash_code(name, len); |
| oop string = StringTable::the_table()->lookup_shared(name, len, hash); |
| if (string != NULL) { |
| return string; |
| } |
| if (StringTable::_alt_hash) { |
| hash = hash_string(name, len, true); |
| } |
| return StringTable::the_table()->do_lookup(name, len, hash); |
| } |
| |
| class StringTableGet : public StackObj { |
| Thread* _thread; |
| Handle _return; |
| public: |
| StringTableGet(Thread* thread) : _thread(thread) {} |
| void operator()(WeakHandle<vm_string_table_data>* val) { |
| oop result = val->resolve(); |
| assert(result != NULL, "Result should be reachable"); |
| _return = Handle(_thread, result); |
| } |
| oop get_res_oop() { |
| return _return(); |
| } |
| }; |
| |
| oop StringTable::do_lookup(const jchar* name, int len, uintx hash) { |
| Thread* thread = Thread::current(); |
| StringTableLookupJchar lookup(thread, hash, name, len); |
| StringTableGet stg(thread); |
| bool rehash_warning; |
| _local_table->get(thread, lookup, stg, &rehash_warning); |
| if (rehash_warning) { |
| _needs_rehashing = true; |
| } |
| return stg.get_res_oop(); |
| } |
| |
| // Interning |
| oop StringTable::intern(Symbol* symbol, TRAPS) { |
| if (symbol == NULL) return NULL; |
| ResourceMark rm(THREAD); |
| int length; |
| jchar* chars = symbol->as_unicode(length); |
| Handle string; |
| oop result = intern(string, chars, length, CHECK_NULL); |
| return result; |
| } |
| |
| oop StringTable::intern(oop string, TRAPS) { |
| if (string == NULL) return NULL; |
| ResourceMark rm(THREAD); |
| int length; |
| Handle h_string (THREAD, string); |
| jchar* chars = java_lang_String::as_unicode_string(string, length, |
| CHECK_NULL); |
| oop result = intern(h_string, chars, length, CHECK_NULL); |
| return result; |
| } |
| |
| oop StringTable::intern(const char* utf8_string, TRAPS) { |
| if (utf8_string == NULL) return NULL; |
| ResourceMark rm(THREAD); |
| int length = UTF8::unicode_length(utf8_string); |
| jchar* chars = NEW_RESOURCE_ARRAY(jchar, length); |
| UTF8::convert_to_unicode(utf8_string, chars, length); |
| Handle string; |
| oop result = intern(string, chars, length, CHECK_NULL); |
| return result; |
| } |
| |
| oop StringTable::intern(Handle string_or_null_h, const jchar* name, int len, TRAPS) { |
| // shared table always uses java_lang_String::hash_code |
| unsigned int hash = java_lang_String::hash_code(name, len); |
| oop found_string = StringTable::the_table()->lookup_shared(name, len, hash); |
| if (found_string != NULL) { |
| return found_string; |
| } |
| if (StringTable::_alt_hash) { |
| hash = hash_string(name, len, true); |
| } |
| return StringTable::the_table()->do_intern(string_or_null_h, name, len, |
| hash, CHECK_NULL); |
| } |
| |
| class StringTableCreateEntry : public StackObj { |
| private: |
| Thread* _thread; |
| Handle _return; |
| Handle _store; |
| public: |
| StringTableCreateEntry(Thread* thread, Handle store) |
| : _thread(thread), _store(store) {} |
| |
| WeakHandle<vm_string_table_data> operator()() { // No dups found |
| WeakHandle<vm_string_table_data> wh = |
| WeakHandle<vm_string_table_data>::create(_store); |
| return wh; |
| } |
| void operator()(bool inserted, WeakHandle<vm_string_table_data>* val) { |
| oop result = val->resolve(); |
| assert(result != NULL, "Result should be reachable"); |
| _return = Handle(_thread, result); |
| } |
| oop get_return() const { |
| return _return(); |
| } |
| }; |
| |
| oop StringTable::do_intern(Handle string_or_null_h, const jchar* name, |
| int len, uintx hash, TRAPS) { |
| HandleMark hm(THREAD); // cleanup strings created |
| Handle string_h; |
| |
| if (!string_or_null_h.is_null()) { |
| string_h = string_or_null_h; |
| } else { |
| string_h = java_lang_String::create_from_unicode(name, len, CHECK_NULL); |
| } |
| |
| // Deduplicate the string before it is interned. Note that we should never |
| // deduplicate a string after it has been interned. Doing so will counteract |
| // compiler optimizations done on e.g. interned string literals. |
| Universe::heap()->deduplicate_string(string_h()); |
| |
| assert(java_lang_String::equals(string_h(), name, len), |
| "string must be properly initialized"); |
| assert(len == java_lang_String::length(string_h()), "Must be same length"); |
| StringTableLookupOop lookup(THREAD, hash, string_h); |
| StringTableCreateEntry stc(THREAD, string_h); |
| |
| bool rehash_warning; |
| _local_table->get_insert_lazy(THREAD, lookup, stc, stc, &rehash_warning); |
| if (rehash_warning) { |
| _needs_rehashing = true; |
| } |
| return stc.get_return(); |
| } |
| |
| // GC support |
| class StringTableIsAliveCounter : public BoolObjectClosure { |
| BoolObjectClosure* _real_boc; |
| public: |
| size_t _count; |
| size_t _count_total; |
| StringTableIsAliveCounter(BoolObjectClosure* boc) : _real_boc(boc), _count(0), |
| _count_total(0) {} |
| bool do_object_b(oop obj) { |
| bool ret = _real_boc->do_object_b(obj); |
| if (!ret) { |
| ++_count; |
| } |
| ++_count_total; |
| return ret; |
| } |
| }; |
| |
| void StringTable::unlink_or_oops_do(BoolObjectClosure* is_alive, OopClosure* f, |
| size_t* processed, size_t* removed) { |
| DoNothingClosure dnc; |
| assert(is_alive != NULL, "No closure"); |
| StringTableIsAliveCounter stiac(is_alive); |
| OopClosure* tmp = f != NULL ? f : &dnc; |
| |
| StringTable::the_table()->_weak_handles->weak_oops_do(&stiac, tmp); |
| |
| // This is the serial case without ParState. |
| // Just set the correct number and check for a cleaning phase. |
| the_table()->_uncleaned_items_count = stiac._count; |
| StringTable::the_table()->check_concurrent_work(); |
| |
| if (processed != NULL) { |
| *processed = stiac._count_total; |
| } |
| if (removed != NULL) { |
| *removed = stiac._count; |
| } |
| } |
| |
| void StringTable::oops_do(OopClosure* f) { |
| assert(f != NULL, "No closure"); |
| StringTable::the_table()->_weak_handles->oops_do(f); |
| } |
| |
| void StringTable::possibly_parallel_unlink( |
| OopStorage::ParState<false, false>* _par_state_string, BoolObjectClosure* cl, |
| size_t* processed, size_t* removed) |
| { |
| DoNothingClosure dnc; |
| assert(cl != NULL, "No closure"); |
| StringTableIsAliveCounter stiac(cl); |
| |
| _par_state_string->weak_oops_do(&stiac, &dnc); |
| |
| // Accumulate the dead strings. |
| the_table()->add_items_count_to_clean(stiac._count); |
| |
| *processed = stiac._count_total; |
| *removed = stiac._count; |
| } |
| |
| void StringTable::possibly_parallel_oops_do( |
| OopStorage::ParState<false /* concurrent */, false /* const */>* |
| _par_state_string, OopClosure* f) |
| { |
| assert(f != NULL, "No closure"); |
| _par_state_string->oops_do(f); |
| } |
| |
| // Concurrent work |
| void StringTable::grow(JavaThread* jt) { |
| StringTableHash::GrowTask gt(_local_table); |
| if (!gt.prepare(jt)) { |
| return; |
| } |
| log_trace(stringtable)("Started to grow"); |
| { |
| TraceTime timer("Grow", TRACETIME_LOG(Debug, stringtable, perf)); |
| while (gt.do_task(jt)) { |
| gt.pause(jt); |
| { |
| ThreadBlockInVM tbivm(jt); |
| } |
| gt.cont(jt); |
| } |
| } |
| gt.done(jt); |
| _current_size = table_size(); |
| log_debug(stringtable)("Grown to size:" SIZE_FORMAT, _current_size); |
| } |
| |
| struct StringTableDoDelete : StackObj { |
| void operator()(WeakHandle<vm_string_table_data>* val) { |
| /* do nothing */ |
| } |
| }; |
| |
| struct StringTableDeleteCheck : StackObj { |
| long _count; |
| long _item; |
| StringTableDeleteCheck() : _count(0), _item(0) {} |
| bool operator()(WeakHandle<vm_string_table_data>* val) { |
| ++_item; |
| oop tmp = val->peek(); |
| if (tmp == NULL) { |
| ++_count; |
| return true; |
| } else { |
| return false; |
| } |
| } |
| }; |
| |
| void StringTable::clean_dead_entries(JavaThread* jt) { |
| StringTableHash::BulkDeleteTask bdt(_local_table); |
| if (!bdt.prepare(jt)) { |
| return; |
| } |
| |
| StringTableDeleteCheck stdc; |
| StringTableDoDelete stdd; |
| { |
| TraceTime timer("Clean", TRACETIME_LOG(Debug, stringtable, perf)); |
| while(bdt.do_task(jt, stdc, stdd)) { |
| bdt.pause(jt); |
| { |
| ThreadBlockInVM tbivm(jt); |
| } |
| bdt.cont(jt); |
| } |
| bdt.done(jt); |
| } |
| log_debug(stringtable)("Cleaned %ld of %ld", stdc._count, stdc._item); |
| } |
| |
| void StringTable::check_concurrent_work() { |
| if (_has_work) { |
| return; |
| } |
| |
| double load_factor = StringTable::get_load_factor(); |
| double dead_factor = StringTable::get_dead_factor(); |
| // We should clean/resize if we have more dead than alive, |
| // more items than preferred load factor or |
| // more dead items than water mark. |
| if ((dead_factor > load_factor) || |
| (load_factor > PREF_AVG_LIST_LEN) || |
| (dead_factor > CLEAN_DEAD_HIGH_WATER_MARK)) { |
| log_debug(stringtable)("Concurrent work triggered, live factor:%g dead factor:%g", |
| load_factor, dead_factor); |
| trigger_concurrent_work(); |
| } |
| } |
| |
| void StringTable::concurrent_work(JavaThread* jt) { |
| _has_work = false; |
| double load_factor = get_load_factor(); |
| log_debug(stringtable, perf)("Concurrent work, live factor: %g", load_factor); |
| // We prefer growing, since that also removes dead items |
| if (load_factor > PREF_AVG_LIST_LEN && !_local_table->is_max_size_reached()) { |
| grow(jt); |
| } else { |
| clean_dead_entries(jt); |
| } |
| } |
| |
| void StringTable::do_concurrent_work(JavaThread* jt) { |
| StringTable::the_table()->concurrent_work(jt); |
| } |
| |
| // Rehash |
| bool StringTable::do_rehash() { |
| if (!_local_table->is_safepoint_safe()) { |
| return false; |
| } |
| |
| // We use max size |
| StringTableHash* new_table = new StringTableHash(END_SIZE, END_SIZE, REHASH_LEN); |
| // Use alt hash from now on |
| _alt_hash = true; |
| if (!_local_table->try_move_nodes_to(Thread::current(), new_table)) { |
| _alt_hash = false; |
| delete new_table; |
| return false; |
| } |
| |
| // free old table |
| delete _local_table; |
| _local_table = new_table; |
| |
| return true; |
| } |
| |
| void StringTable::try_rehash_table() { |
| static bool rehashed = false; |
| log_debug(stringtable)("Table imbalanced, rehashing called."); |
| |
| // Grow instead of rehash. |
| if (get_load_factor() > PREF_AVG_LIST_LEN && |
| !_local_table->is_max_size_reached()) { |
| log_debug(stringtable)("Choosing growing over rehashing."); |
| trigger_concurrent_work(); |
| _needs_rehashing = false; |
| return; |
| } |
| // Already rehashed. |
| if (rehashed) { |
| log_warning(stringtable)("Rehashing already done, still long lists."); |
| trigger_concurrent_work(); |
| _needs_rehashing = false; |
| return; |
| } |
| |
| murmur_seed = AltHashing::compute_seed(); |
| { |
| if (do_rehash()) { |
| rehashed = true; |
| } else { |
| log_info(stringtable)("Resizes in progress rehashing skipped."); |
| } |
| } |
| _needs_rehashing = false; |
| } |
| |
| void StringTable::rehash_table() { |
| StringTable::the_table()->try_rehash_table(); |
| } |
| |
| // Statistics |
| static int literal_size(oop obj) { |
| // NOTE: this would over-count if (pre-JDK8) |
| // java_lang_Class::has_offset_field() is true and the String.value array is |
| // shared by several Strings. However, starting from JDK8, the String.value |
| // array is not shared anymore. |
| if (obj == NULL) { |
| return 0; |
| } else if (obj->klass() == SystemDictionary::String_klass()) { |
| return (obj->size() + java_lang_String::value(obj)->size()) * HeapWordSize; |
| } else { |
| return obj->size(); |
| } |
| } |
| |
| struct SizeFunc : StackObj { |
| size_t operator()(WeakHandle<vm_string_table_data>* val) { |
| oop s = val->peek(); |
| if (s == NULL) { |
| // Dead |
| return 0; |
| } |
| return literal_size(s); |
| }; |
| }; |
| |
| void StringTable::print_table_statistics(outputStream* st, |
| const char* table_name) { |
| SizeFunc sz; |
| _local_table->statistics_to(Thread::current(), sz, st, table_name); |
| } |
| |
| // Verification |
| class VerifyStrings : StackObj { |
| public: |
| bool operator()(WeakHandle<vm_string_table_data>* val) { |
| oop s = val->peek(); |
| if (s != NULL) { |
| assert(java_lang_String::length(s) >= 0, "Length on string must work."); |
| } |
| return true; |
| }; |
| }; |
| |
| // This verification is part of Universe::verify() and needs to be quick. |
| void StringTable::verify() { |
| Thread* thr = Thread::current(); |
| VerifyStrings vs; |
| if (!the_table()->_local_table->try_scan(thr, vs)) { |
| log_info(stringtable)("verify unavailable at this moment"); |
| } |
| } |
| |
| // Verification and comp |
| class VerifyCompStrings : StackObj { |
| GrowableArray<oop>* _oops; |
| public: |
| size_t _errors; |
| VerifyCompStrings(GrowableArray<oop>* oops) : _oops(oops), _errors(0) {} |
| bool operator()(WeakHandle<vm_string_table_data>* val) { |
| oop s = val->resolve(); |
| if (s == NULL) { |
| return true; |
| } |
| int len = _oops->length(); |
| for (int i = 0; i < len; i++) { |
| bool eq = java_lang_String::equals(s, _oops->at(i)); |
| assert(!eq, "Duplicate strings"); |
| if (eq) { |
| _errors++; |
| } |
| } |
| _oops->push(s); |
| return true; |
| }; |
| }; |
| |
| size_t StringTable::verify_and_compare_entries() { |
| Thread* thr = Thread::current(); |
| GrowableArray<oop>* oops = |
| new (ResourceObj::C_HEAP, mtInternal) |
| GrowableArray<oop>((int)the_table()->_current_size, true); |
| |
| VerifyCompStrings vcs(oops); |
| if (!the_table()->_local_table->try_scan(thr, vcs)) { |
| log_info(stringtable)("verify unavailable at this moment"); |
| } |
| delete oops; |
| return vcs._errors; |
| } |
| |
| // Dumping |
| class PrintString : StackObj { |
| Thread* _thr; |
| outputStream* _st; |
| public: |
| PrintString(Thread* thr, outputStream* st) : _thr(thr), _st(st) {} |
| bool operator()(WeakHandle<vm_string_table_data>* val) { |
| oop s = val->peek(); |
| if (s == NULL) { |
| return true; |
| } |
| typeArrayOop value = java_lang_String::value_no_keepalive(s); |
| int length = java_lang_String::length(s); |
| bool is_latin1 = java_lang_String::is_latin1(s); |
| |
| if (length <= 0) { |
| _st->print("%d: ", length); |
| } else { |
| ResourceMark rm(_thr); |
| int utf8_length = length; |
| char* utf8_string; |
| |
| if (!is_latin1) { |
| jchar* chars = value->char_at_addr(0); |
| utf8_string = UNICODE::as_utf8(chars, utf8_length); |
| } else { |
| jbyte* bytes = value->byte_at_addr(0); |
| utf8_string = UNICODE::as_utf8(bytes, utf8_length); |
| } |
| |
| _st->print("%d: ", utf8_length); |
| HashtableTextDump::put_utf8(_st, utf8_string, utf8_length); |
| } |
| _st->cr(); |
| return true; |
| }; |
| }; |
| |
| void StringTable::dump(outputStream* st, bool verbose) { |
| if (!verbose) { |
| the_table()->print_table_statistics(st, "StringTable"); |
| } else { |
| Thread* thr = Thread::current(); |
| ResourceMark rm(thr); |
| st->print_cr("VERSION: 1.1"); |
| PrintString ps(thr, st); |
| if (!the_table()->_local_table->try_scan(thr, ps)) { |
| st->print_cr("dump unavailable at this moment"); |
| } |
| } |
| } |
| |
| // Utility for dumping strings |
| StringtableDCmd::StringtableDCmd(outputStream* output, bool heap) : |
| DCmdWithParser(output, heap), |
| _verbose("-verbose", "Dump the content of each string in the table", |
| "BOOLEAN", false, "false") { |
| _dcmdparser.add_dcmd_option(&_verbose); |
| } |
| |
| void StringtableDCmd::execute(DCmdSource source, TRAPS) { |
| VM_DumpHashtable dumper(output(), VM_DumpHashtable::DumpStrings, |
| _verbose.value()); |
| VMThread::execute(&dumper); |
| } |
| |
| int StringtableDCmd::num_arguments() { |
| ResourceMark rm; |
| StringtableDCmd* dcmd = new StringtableDCmd(NULL, false); |
| if (dcmd != NULL) { |
| DCmdMark mark(dcmd); |
| return dcmd->_dcmdparser.num_arguments(); |
| } else { |
| return 0; |
| } |
| } |
| |
| // Sharing |
| #if INCLUDE_CDS_JAVA_HEAP |
| oop StringTable::lookup_shared(const jchar* name, int len, unsigned int hash) { |
| assert(hash == java_lang_String::hash_code(name, len), |
| "hash must be computed using java_lang_String::hash_code"); |
| return _shared_table.lookup(name, hash, len); |
| } |
| |
| oop StringTable::create_archived_string(oop s, Thread* THREAD) { |
| assert(DumpSharedSpaces, "this function is only used with -Xshare:dump"); |
| |
| if (MetaspaceShared::is_archive_object(s)) { |
| return s; |
| } |
| |
| oop new_s = NULL; |
| typeArrayOop v = java_lang_String::value_no_keepalive(s); |
| typeArrayOop new_v = |
| (typeArrayOop)MetaspaceShared::archive_heap_object(v, THREAD); |
| if (new_v == NULL) { |
| return NULL; |
| } |
| new_s = MetaspaceShared::archive_heap_object(s, THREAD); |
| if (new_s == NULL) { |
| return NULL; |
| } |
| |
| // adjust the pointer to the 'value' field in the new String oop |
| java_lang_String::set_value_raw(new_s, new_v); |
| return new_s; |
| } |
| |
| struct CopyToArchive : StackObj { |
| CompactHashtableWriter* _writer; |
| CopyToArchive(CompactHashtableWriter* writer) : _writer(writer) {} |
| bool operator()(WeakHandle<vm_string_table_data>* val) { |
| oop s = val->peek(); |
| if (s == NULL) { |
| return true; |
| } |
| unsigned int hash = java_lang_String::hash_code(s); |
| if (hash == 0) { |
| // We do not archive Strings with a 0 hashcode because ...... |
| return true; |
| } |
| |
| java_lang_String::set_hash(s, hash); |
| oop new_s = StringTable::create_archived_string(s, Thread::current()); |
| if (new_s == NULL) { |
| return true; |
| } |
| |
| val->replace(new_s); |
| // add to the compact table |
| _writer->add(hash, CompressedOops::encode(new_s)); |
| return true; |
| } |
| }; |
| |
| void StringTable::copy_shared_string_table(CompactHashtableWriter* writer) { |
| assert(MetaspaceShared::is_heap_object_archiving_allowed(), "must be"); |
| |
| CopyToArchive copy(writer); |
| StringTable::the_table()->_local_table->do_scan(Thread::current(), copy); |
| } |
| |
| void StringTable::write_to_archive() { |
| assert(MetaspaceShared::is_heap_object_archiving_allowed(), "must be"); |
| |
| _shared_table.reset(); |
| int num_buckets = CompactHashtableWriter::default_num_buckets( |
| StringTable::the_table()->_items_count); |
| CompactHashtableWriter writer(num_buckets, |
| &MetaspaceShared::stats()->string); |
| |
| // Copy the interned strings into the "string space" within the java heap |
| copy_shared_string_table(&writer); |
| writer.dump(&_shared_table, "string"); |
| } |
| |
| void StringTable::serialize_shared_table_header(SerializeClosure* soc) { |
| _shared_table.serialize_header(soc); |
| |
| if (soc->writing()) { |
| // Sanity. Make sure we don't use the shared table at dump time |
| _shared_table.reset(); |
| } else if (!_shared_string_mapped) { |
| _shared_table.reset(); |
| } |
| } |
| |
| class SharedStringIterator { |
| OopClosure* _oop_closure; |
| public: |
| SharedStringIterator(OopClosure* f) : _oop_closure(f) {} |
| void do_value(oop string) { |
| _oop_closure->do_oop(&string); |
| } |
| }; |
| |
| void StringTable::shared_oops_do(OopClosure* f) { |
| SharedStringIterator iter(f); |
| _shared_table.iterate(&iter); |
| } |
| #endif //INCLUDE_CDS_JAVA_HEAP |