view src/share/vm/oops/methodDataKlass.cpp @ 3917:eca1193ca245

4965777: GC changes to support use of discovered field for pending references Summary: If and when the reference handler thread is able to use the discovered field to link reference objects in its pending list, so will GC. In that case, GC will scan through this field once a reference object has been placed on the pending list, but not scan that field before that stage, as the field is used by the concurrent GC thread to link discovered objects. When ReferenceHandleR thread does not use the discovered field for the purpose of linking the elements in the pending list, as would be the case in older JDKs, the JVM will fall back to the old behaviour of using the next field for that purpose. Reviewed-by: jcoomes, mchung, stefank
author ysr
date Wed, 07 Sep 2011 13:55:42 -0700
parents e5383553fd4e
children f7251c729b31
line wrap: on
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/*
 * Copyright (c) 2000, 2011, 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 "gc_implementation/shared/markSweep.inline.hpp"
#include "gc_interface/collectedHeap.inline.hpp"
#include "memory/gcLocker.hpp"
#include "memory/resourceArea.hpp"
#include "memory/universe.inline.hpp"
#include "oops/klassOop.hpp"
#include "oops/methodDataKlass.hpp"
#include "oops/methodDataOop.hpp"
#include "oops/oop.inline.hpp"
#include "oops/oop.inline2.hpp"
#include "runtime/handles.inline.hpp"
#ifndef SERIALGC
#include "gc_implementation/parallelScavenge/psScavenge.inline.hpp"
#include "oops/oop.pcgc.inline.hpp"
#endif

klassOop methodDataKlass::create_klass(TRAPS) {
  methodDataKlass o;
  KlassHandle h_this_klass(THREAD, Universe::klassKlassObj());
  KlassHandle k = base_create_klass(h_this_klass, header_size(),
                                    o.vtbl_value(), CHECK_NULL);
  // Make sure size calculation is right
  assert(k()->size() == align_object_size(header_size()),
         "wrong size for object");
  return k();
}


int methodDataKlass::oop_size(oop obj) const {
  assert(obj->is_methodData(), "must be method data oop");
  return methodDataOop(obj)->object_size();
}


bool methodDataKlass::oop_is_parsable(oop obj) const {
  assert(obj->is_methodData(), "must be method data oop");
  return methodDataOop(obj)->object_is_parsable();
}


methodDataOop methodDataKlass::allocate(methodHandle method, TRAPS) {
  int size = methodDataOopDesc::compute_allocation_size_in_words(method);
  KlassHandle h_k(THREAD, as_klassOop());
  methodDataOop mdo =
    (methodDataOop)CollectedHeap::permanent_obj_allocate(h_k, size, CHECK_NULL);
  assert(!mdo->is_parsable(), "not expecting parsability yet.");
  No_Safepoint_Verifier no_safepoint;  // init function atomic wrt GC
  mdo->initialize(method);

  assert(mdo->is_parsable(), "should be parsable here.");
  assert(size == mdo->object_size(), "wrong size for methodDataOop");
  return mdo;
}


void methodDataKlass::oop_follow_contents(oop obj) {
  assert (obj->is_methodData(), "object must be method data");
  methodDataOop m = methodDataOop(obj);

  obj->follow_header();
  MarkSweep::mark_and_push(m->adr_method());
  ResourceMark rm;
  for (ProfileData* data = m->first_data();
       m->is_valid(data);
       data = m->next_data(data)) {
    data->follow_contents();
  }
}

#ifndef SERIALGC
void methodDataKlass::oop_follow_contents(ParCompactionManager* cm,
                                          oop obj) {
  assert (obj->is_methodData(), "object must be method data");
  methodDataOop m = methodDataOop(obj);

  obj->follow_header(cm);
  PSParallelCompact::mark_and_push(cm, m->adr_method());
  ResourceMark rm;
  for (ProfileData* data = m->first_data();
       m->is_valid(data);
       data = m->next_data(data)) {
    data->follow_contents(cm);
  }
}
#endif // SERIALGC


int methodDataKlass::oop_oop_iterate(oop obj, OopClosure* blk) {
  assert (obj->is_methodData(), "object must be method data");
  methodDataOop m = methodDataOop(obj);
  // Get size before changing pointers
  // Don't call size() or oop_size() since that is a virtual call.
  int size = m->object_size();

  obj->oop_iterate_header(blk);
  blk->do_oop(m->adr_method());
  ResourceMark rm;
  for (ProfileData* data = m->first_data();
       m->is_valid(data);
       data = m->next_data(data)) {
    data->oop_iterate(blk);
  }
  return size;
}

int methodDataKlass::oop_oop_iterate_m(oop obj, OopClosure* blk, MemRegion mr) {
  assert (obj->is_methodData(), "object must be method data");
  methodDataOop m = methodDataOop(obj);
  // Get size before changing pointers
  // Don't call size() or oop_size() since that is a virtual call.
  int size = m->object_size();

  obj->oop_iterate_header(blk, mr);
  oop* adr = m->adr_method();
  if (mr.contains(adr)) {
    blk->do_oop(m->adr_method());
  }
  ResourceMark rm;
  for (ProfileData* data = m->first_data();
       m->is_valid(data);
       data = m->next_data(data)) {
    data->oop_iterate_m(blk, mr);
  }
  return size;
}

int methodDataKlass::oop_adjust_pointers(oop obj) {
  assert(obj->is_methodData(), "should be method data");
  methodDataOop m = methodDataOop(obj);
  // Get size before changing pointers
  // Don't call size() or oop_size() since that is a virtual call.
  int size = m->object_size();

  obj->adjust_header();
  MarkSweep::adjust_pointer(m->adr_method());
  ResourceMark rm;
  ProfileData* data;
  for (data = m->first_data(); m->is_valid(data); data = m->next_data(data)) {
    data->adjust_pointers();
  }
  return size;
}


#ifndef SERIALGC
void methodDataKlass::oop_push_contents(PSPromotionManager* pm, oop obj) {
  assert (obj->is_methodData(), "object must be method data");
  methodDataOop m = methodDataOop(obj);
  // This should never point into the young gen.
  assert(!PSScavenge::should_scavenge(m->adr_method()), "Sanity");
}

int methodDataKlass::oop_update_pointers(ParCompactionManager* cm, oop obj) {
  assert(obj->is_methodData(), "should be method data");
  methodDataOop m = methodDataOop(obj);

  PSParallelCompact::adjust_pointer(m->adr_method());

  ResourceMark rm;
  ProfileData* data;
  for (data = m->first_data(); m->is_valid(data); data = m->next_data(data)) {
    data->update_pointers();
  }
  return m->object_size();
}
#endif // SERIALGC

#ifndef PRODUCT

// Printing
void methodDataKlass::oop_print_on(oop obj, outputStream* st) {
  assert(obj->is_methodData(), "should be method data");
  methodDataOop m = methodDataOop(obj);
  st->print("method data for ");
  m->method()->print_value_on(st);
  st->cr();
  m->print_data_on(st);
}

#endif //PRODUCT

void methodDataKlass::oop_print_value_on(oop obj, outputStream* st) {
  assert(obj->is_methodData(), "should be method data");
  methodDataOop m = methodDataOop(obj);
  st->print("method data for ");
  m->method()->print_value_on(st);
}

const char* methodDataKlass::internal_name() const {
  return "{method data}";
}


// Verification
void methodDataKlass::oop_verify_on(oop obj, outputStream* st) {
  Klass::oop_verify_on(obj, st);
  guarantee(obj->is_methodData(), "object must be method data");
  methodDataOop m = methodDataOop(obj);
  guarantee(m->is_perm(), "should be in permspace");
  m->verify_data_on(st);
}