8231198: Shenandoah: heap walking should visit all roots most of the time
Reviewed-by: zgu, rkennke
/*
* Copyright (c) 2019, Red Hat, Inc. All rights reserved.
*
* 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.
*
*/
#ifndef SHARE_GC_SHENANDOAH_SHENANDOAHCLOSURES_INLINE_HPP
#define SHARE_GC_SHENANDOAH_SHENANDOAHCLOSURES_INLINE_HPP
#include "gc/shenandoah/shenandoahAsserts.hpp"
#include "gc/shenandoah/shenandoahClosures.hpp"
#include "gc/shenandoah/shenandoahHeap.inline.hpp"
#include "oops/compressedOops.inline.hpp"
#include "runtime/thread.hpp"
ShenandoahForwardedIsAliveClosure::ShenandoahForwardedIsAliveClosure() :
_mark_context(ShenandoahHeap::heap()->marking_context()) {
}
bool ShenandoahForwardedIsAliveClosure::do_object_b(oop obj) {
if (CompressedOops::is_null(obj)) {
return false;
}
obj = ShenandoahBarrierSet::resolve_forwarded_not_null(obj);
shenandoah_assert_not_forwarded_if(NULL, obj,
(ShenandoahHeap::heap()->is_concurrent_mark_in_progress() ||
ShenandoahHeap::heap()->is_concurrent_traversal_in_progress()));
return _mark_context->is_marked(obj);
}
ShenandoahIsAliveClosure::ShenandoahIsAliveClosure() :
_mark_context(ShenandoahHeap::heap()->marking_context()) {
}
bool ShenandoahIsAliveClosure::do_object_b(oop obj) {
if (CompressedOops::is_null(obj)) {
return false;
}
shenandoah_assert_not_forwarded(NULL, obj);
return _mark_context->is_marked(obj);
}
BoolObjectClosure* ShenandoahIsAliveSelector::is_alive_closure() {
return ShenandoahHeap::heap()->has_forwarded_objects() ?
reinterpret_cast<BoolObjectClosure*>(&_fwd_alive_cl) :
reinterpret_cast<BoolObjectClosure*>(&_alive_cl);
}
ShenandoahUpdateRefsClosure::ShenandoahUpdateRefsClosure() :
_heap(ShenandoahHeap::heap()) {
}
template <class T>
void ShenandoahUpdateRefsClosure::do_oop_work(T* p) {
T o = RawAccess<>::oop_load(p);
if (!CompressedOops::is_null(o)) {
oop obj = CompressedOops::decode_not_null(o);
_heap->update_with_forwarded_not_null(p, obj);
}
}
void ShenandoahUpdateRefsClosure::do_oop(oop* p) { do_oop_work(p); }
void ShenandoahUpdateRefsClosure::do_oop(narrowOop* p) { do_oop_work(p); }
ShenandoahEvacuateUpdateRootsClosure::ShenandoahEvacuateUpdateRootsClosure() :
_heap(ShenandoahHeap::heap()), _thread(Thread::current()) {
}
template <class T>
void ShenandoahEvacuateUpdateRootsClosure::do_oop_work(T* p) {
assert(_heap->is_evacuation_in_progress(), "Only do this when evacuation is in progress");
T o = RawAccess<>::oop_load(p);
if (! CompressedOops::is_null(o)) {
oop obj = CompressedOops::decode_not_null(o);
if (_heap->in_collection_set(obj)) {
shenandoah_assert_marked(p, obj);
oop resolved = ShenandoahBarrierSet::resolve_forwarded_not_null(obj);
if (resolved == obj) {
resolved = _heap->evacuate_object(obj, _thread);
}
RawAccess<IS_NOT_NULL>::oop_store(p, resolved);
}
}
}
void ShenandoahEvacuateUpdateRootsClosure::do_oop(oop* p) {
do_oop_work(p);
}
void ShenandoahEvacuateUpdateRootsClosure::do_oop(narrowOop* p) {
do_oop_work(p);
}
ShenandoahEvacUpdateOopStorageRootsClosure::ShenandoahEvacUpdateOopStorageRootsClosure() :
_heap(ShenandoahHeap::heap()), _thread(Thread::current()) {
}
void ShenandoahEvacUpdateOopStorageRootsClosure::do_oop(oop* p) {
assert(_heap->is_evacuation_in_progress(), "Only do this when evacuation is in progress");
oop obj = RawAccess<>::oop_load(p);
if (! CompressedOops::is_null(obj)) {
if (_heap->in_collection_set(obj)) {
shenandoah_assert_marked(p, obj);
oop resolved = ShenandoahBarrierSet::resolve_forwarded_not_null(obj);
if (resolved == obj) {
resolved = _heap->evacuate_object(obj, _thread);
}
Atomic::cmpxchg(resolved, p, obj);
}
}
}
void ShenandoahEvacUpdateOopStorageRootsClosure::do_oop(narrowOop* p) {
ShouldNotReachHere();
}
#ifdef ASSERT
template <class T>
void ShenandoahAssertNotForwardedClosure::do_oop_work(T* p) {
T o = RawAccess<>::oop_load(p);
if (!CompressedOops::is_null(o)) {
oop obj = CompressedOops::decode_not_null(o);
shenandoah_assert_not_forwarded(p, obj);
}
}
void ShenandoahAssertNotForwardedClosure::do_oop(narrowOop* p) { do_oop_work(p); }
void ShenandoahAssertNotForwardedClosure::do_oop(oop* p) { do_oop_work(p); }
#endif
#endif // SHARE_GC_SHENANDOAH_SHENANDOAHCLOSURES_HPP