Thu, 24 Mar 2011 15:47:01 -0700
7029036: Card-table verification hangs with all framework collectors, except G1, even before the first GC
Summary: When verifying clean card ranges, use memory-range-bounded iteration over oops of objects overlapping that range, thus avoiding the otherwise quadratic worst-case cost of scanning large object arrays.
Reviewed-by: jmasa, jwilhelm, tonyp
1 /*
2 * Copyright (c) 1997, 2010, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
25 #include "precompiled.hpp"
26 #include "memory/iterator.hpp"
27 #include "oops/oop.inline.hpp"
29 #ifdef ASSERT
30 bool OopClosure::_must_remember_klasses = false;
31 #endif
33 void ObjectToOopClosure::do_object(oop obj) {
34 obj->oop_iterate(_cl);
35 }
37 void VoidClosure::do_void() {
38 ShouldNotCallThis();
39 }
41 #ifdef ASSERT
42 bool OopClosure::must_remember_klasses() {
43 return _must_remember_klasses;
44 }
45 void OopClosure::set_must_remember_klasses(bool v) {
46 _must_remember_klasses = v;
47 }
48 #endif
51 MarkingCodeBlobClosure::MarkScope::MarkScope(bool activate)
52 : _active(activate)
53 {
54 if (_active) nmethod::oops_do_marking_prologue();
55 }
57 MarkingCodeBlobClosure::MarkScope::~MarkScope() {
58 if (_active) nmethod::oops_do_marking_epilogue();
59 }
61 void MarkingCodeBlobClosure::do_code_blob(CodeBlob* cb) {
62 nmethod* nm = cb->as_nmethod_or_null();
63 if (nm == NULL) return;
64 if (!nm->test_set_oops_do_mark()) {
65 NOT_PRODUCT(if (TraceScavenge) nm->print_on(tty, "oops_do, 1st visit\n"));
66 do_newly_marked_nmethod(nm);
67 } else {
68 NOT_PRODUCT(if (TraceScavenge) nm->print_on(tty, "oops_do, skipped on 2nd visit\n"));
69 }
70 }
72 void CodeBlobToOopClosure::do_newly_marked_nmethod(nmethod* nm) {
73 nm->oops_do(_cl, /*do_strong_roots_only=*/ true);
74 }
76 void CodeBlobToOopClosure::do_code_blob(CodeBlob* cb) {
77 if (!_do_marking) {
78 nmethod* nm = cb->as_nmethod_or_null();
79 NOT_PRODUCT(if (TraceScavenge && Verbose && nm != NULL) nm->print_on(tty, "oops_do, unmarked visit\n"));
80 // This assert won't work, since there are lots of mini-passes
81 // (mostly in debug mode) that co-exist with marking phases.
82 //assert(!(cb->is_nmethod() && ((nmethod*)cb)->test_oops_do_mark()), "found marked nmethod during mark-free phase");
83 if (nm != NULL) {
84 nm->oops_do(_cl);
85 }
86 } else {
87 MarkingCodeBlobClosure::do_code_blob(cb);
88 }
89 }