8048248: G1 Class Unloading after completing a concurrent mark cycle
Reviewed-by: tschatzl, ehelin, brutisso, coleenp, roland, iveresov
/*
* Copyright (c) 1997, 2013, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*
*/
#include "precompiled.hpp"
#include "prims/jvm.h"
#include "runtime/os.hpp"
#include "utilities/decoder.hpp"
#include "utilities/vmError.hpp"
#if defined(_WINDOWS)
#include "decoder_windows.hpp"
#elif defined(__APPLE__)
#include "decoder_machO.hpp"
#elif defined(AIX)
#include "decoder_aix.hpp"
#else
#include "decoder_elf.hpp"
#endif
AbstractDecoder* Decoder::_shared_decoder = NULL;
AbstractDecoder* Decoder::_error_handler_decoder = NULL;
NullDecoder Decoder::_do_nothing_decoder;
Mutex* Decoder::_shared_decoder_lock = new Mutex(Mutex::native,
"SharedDecoderLock");
AbstractDecoder* Decoder::get_shared_instance() {
assert(_shared_decoder_lock != NULL && _shared_decoder_lock->owned_by_self(),
"Require DecoderLock to enter");
if (_shared_decoder == NULL) {
_shared_decoder = create_decoder();
}
return _shared_decoder;
}
AbstractDecoder* Decoder::get_error_handler_instance() {
if (_error_handler_decoder == NULL) {
_error_handler_decoder = create_decoder();
}
return _error_handler_decoder;
}
AbstractDecoder* Decoder::create_decoder() {
AbstractDecoder* decoder;
#if defined(_WINDOWS)
decoder = new (std::nothrow) WindowsDecoder();
#elif defined (__APPLE__)
decoder = new (std::nothrow)MachODecoder();
#elif defined(AIX)
decoder = new (std::nothrow)AIXDecoder();
#else
decoder = new (std::nothrow)ElfDecoder();
#endif
if (decoder == NULL || decoder->has_error()) {
if (decoder != NULL) {
delete decoder;
}
decoder = &_do_nothing_decoder;
}
return decoder;
}
inline bool DecoderLocker::is_first_error_thread() {
return (os::current_thread_id() == VMError::get_first_error_tid());
}
DecoderLocker::DecoderLocker() :
MutexLockerEx(DecoderLocker::is_first_error_thread() ?
NULL : Decoder::shared_decoder_lock(), true) {
_decoder = is_first_error_thread() ?
Decoder::get_error_handler_instance() : Decoder::get_shared_instance();
assert(_decoder != NULL, "null decoder");
}
Mutex* Decoder::shared_decoder_lock() {
assert(_shared_decoder_lock != NULL, "Just check");
return _shared_decoder_lock;
}
bool Decoder::decode(address addr, char* buf, int buflen, int* offset, const char* modulepath) {
assert(_shared_decoder_lock != NULL, "Just check");
bool error_handling_thread = os::current_thread_id() == VMError::first_error_tid;
MutexLockerEx locker(error_handling_thread ? NULL : _shared_decoder_lock, true);
AbstractDecoder* decoder = error_handling_thread ?
get_error_handler_instance(): get_shared_instance();
assert(decoder != NULL, "null decoder");
return decoder->decode(addr, buf, buflen, offset, modulepath);
}
bool Decoder::decode(address addr, char* buf, int buflen, int* offset, const void* base) {
assert(_shared_decoder_lock != NULL, "Just check");
bool error_handling_thread = os::current_thread_id() == VMError::first_error_tid;
MutexLockerEx locker(error_handling_thread ? NULL : _shared_decoder_lock, true);
AbstractDecoder* decoder = error_handling_thread ?
get_error_handler_instance(): get_shared_instance();
assert(decoder != NULL, "null decoder");
return decoder->decode(addr, buf, buflen, offset, base);
}
bool Decoder::demangle(const char* symbol, char* buf, int buflen) {
assert(_shared_decoder_lock != NULL, "Just check");
bool error_handling_thread = os::current_thread_id() == VMError::first_error_tid;
MutexLockerEx locker(error_handling_thread ? NULL : _shared_decoder_lock, true);
AbstractDecoder* decoder = error_handling_thread ?
get_error_handler_instance(): get_shared_instance();
assert(decoder != NULL, "null decoder");
return decoder->demangle(symbol, buf, buflen);
}
bool Decoder::can_decode_C_frame_in_vm() {
assert(_shared_decoder_lock != NULL, "Just check");
bool error_handling_thread = os::current_thread_id() == VMError::first_error_tid;
MutexLockerEx locker(error_handling_thread ? NULL : _shared_decoder_lock, true);
AbstractDecoder* decoder = error_handling_thread ?
get_error_handler_instance(): get_shared_instance();
assert(decoder != NULL, "null decoder");
return decoder->can_decode_C_frame_in_vm();
}
/*
* Shutdown shared decoder and replace it with
* _do_nothing_decoder. Do nothing with error handler
* instance, since the JVM is going down.
*/
void Decoder::shutdown() {
assert(_shared_decoder_lock != NULL, "Just check");
MutexLockerEx locker(_shared_decoder_lock, true);
if (_shared_decoder != NULL &&
_shared_decoder != &_do_nothing_decoder) {
delete _shared_decoder;
}
_shared_decoder = &_do_nothing_decoder;
}