src/hotspot/share/gc/shenandoah/shenandoahClosures.inline.hpp
author shade
Thu, 19 Sep 2019 20:26:52 +0200
changeset 58232 de9d23469c68
parent 58177 4932dce35882
child 58679 9c3209ff7550
child 58686 0279391875bf
permissions -rw-r--r--
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