hotspot/src/share/vm/memory/iterator.cpp
author johnc
Thu, 15 Aug 2013 10:52:18 +0200
changeset 19339 d247781beec7
parent 14582 490bb6c0df7c
child 22234 da823d78ad65
permissions -rw-r--r--
7145569: G1: optimize nmethods scanning Summary: Add a list of nmethods to the RSet for a region that contain references into the region. Skip scanning the code cache during root scanning and scan the nmethod lists during RSet scanning instead. Reviewed-by: tschatzl, brutisso, mgerdin, twisti, kvn

/*
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 * 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.
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#include "precompiled.hpp"
#include "memory/iterator.hpp"
#include "oops/oop.inline.hpp"

void KlassToOopClosure::do_klass(Klass* k) {
  k->oops_do(_oop_closure);
}

void CLDToOopClosure::do_cld(ClassLoaderData* cld) {
  cld->oops_do(_oop_closure, &_klass_closure, _must_claim_cld);
}

void ObjectToOopClosure::do_object(oop obj) {
  obj->oop_iterate(_cl);
}

void VoidClosure::do_void() {
  ShouldNotCallThis();
}

MarkingCodeBlobClosure::MarkScope::MarkScope(bool activate)
  : _active(activate)
{
  if (_active)  nmethod::oops_do_marking_prologue();
}

MarkingCodeBlobClosure::MarkScope::~MarkScope() {
  if (_active)  nmethod::oops_do_marking_epilogue();
}

void MarkingCodeBlobClosure::do_code_blob(CodeBlob* cb) {
  nmethod* nm = cb->as_nmethod_or_null();
  if (nm == NULL)  return;
  if (!nm->test_set_oops_do_mark()) {
    NOT_PRODUCT(if (TraceScavenge)  nm->print_on(tty, "oops_do, 1st visit\n"));
    do_newly_marked_nmethod(nm);
  } else {
    NOT_PRODUCT(if (TraceScavenge)  nm->print_on(tty, "oops_do, skipped on 2nd visit\n"));
  }
}

void CodeBlobToOopClosure::do_newly_marked_nmethod(nmethod* nm) {
  nm->oops_do(_cl, /*allow_zombie=*/ false);
}

void CodeBlobToOopClosure::do_code_blob(CodeBlob* cb) {
  if (!_do_marking) {
    nmethod* nm = cb->as_nmethod_or_null();
    NOT_PRODUCT(if (TraceScavenge && Verbose && nm != NULL)  nm->print_on(tty, "oops_do, unmarked visit\n"));
    // This assert won't work, since there are lots of mini-passes
    // (mostly in debug mode) that co-exist with marking phases.
    //assert(!(cb->is_nmethod() && ((nmethod*)cb)->test_oops_do_mark()), "found marked nmethod during mark-free phase");
    if (nm != NULL) {
      nm->oops_do(_cl);
    }
  } else {
    MarkingCodeBlobClosure::do_code_blob(cb);
  }
}