Mercurial > jdk8-mips64-public > hotspot / file revision
src/share/vm/gc_implementation/parNew/parOopClosures.inline.hpp@5cfd8d19e546
src/share/vm/gc_implementation/parNew/parOopClosures.inline.hpp
Mon, 26 Jan 2009 12:47:21 -0800
- author
- ysr
- date
- Mon, 26 Jan 2009 12:47:21 -0800
- changeset 969
- 5cfd8d19e546
- parent 548
- ba764ed4b6f2
- child 1907
- c18cbe5936b8
- permissions
- -rw-r--r--
6786503: Overflow list performance can be improved
Summary: Avoid overflow list walk in CMS & ParNew when it is unnecessary. Fix a couple of correctness issues, including a C-heap leak, in ParNew at the intersection of promotion failure, work queue overflow and object array chunking. Add stress testing option and related assertion checking.
Reviewed-by: jmasa
1 /*
2 * Copyright (c) 2007 Sun Microsystems, Inc. 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
20 * CA 95054 USA or visit www.sun.com if you need additional information or
21 * have any questions.
22 *
23 */
25 template <class T> inline void ParScanWeakRefClosure::do_oop_work(T* p) {
26 assert (!oopDesc::is_null(*p), "null weak reference?");
27 oop obj = oopDesc::load_decode_heap_oop_not_null(p);
28 // weak references are sometimes scanned twice; must check
29 // that to-space doesn't already contain this object
30 if ((HeapWord*)obj < _boundary && !_g->to()->is_in_reserved(obj)) {
31 // we need to ensure that it is copied (see comment in
32 // ParScanClosure::do_oop_work).
33 klassOop objK = obj->klass();
34 markOop m = obj->mark();
35 oop new_obj;
36 if (m->is_marked()) { // Contains forwarding pointer.
37 new_obj = ParNewGeneration::real_forwardee(obj);
38 } else {
39 size_t obj_sz = obj->size_given_klass(objK->klass_part());
40 new_obj = ((ParNewGeneration*)_g)->copy_to_survivor_space(_par_scan_state,
41 obj, obj_sz, m);
42 }
43 oopDesc::encode_store_heap_oop_not_null(p, new_obj);
44 }
45 }
47 inline void ParScanWeakRefClosure::do_oop_nv(oop* p) { ParScanWeakRefClosure::do_oop_work(p); }
48 inline void ParScanWeakRefClosure::do_oop_nv(narrowOop* p) { ParScanWeakRefClosure::do_oop_work(p); }
50 template <class T> inline void ParScanClosure::par_do_barrier(T* p) {
51 assert(generation()->is_in_reserved(p), "expected ref in generation");
52 assert(!oopDesc::is_null(*p), "expected non-null object");
53 oop obj = oopDesc::load_decode_heap_oop_not_null(p);
54 // If p points to a younger generation, mark the card.
55 if ((HeapWord*)obj < gen_boundary()) {
56 rs()->write_ref_field_gc_par(p, obj);
57 }
58 }
60 template <class T>
61 inline void ParScanClosure::do_oop_work(T* p,
62 bool gc_barrier,
63 bool root_scan) {
64 assert((!Universe::heap()->is_in_reserved(p) ||
65 generation()->is_in_reserved(p))
66 && (generation()->level() == 0 || gc_barrier),
67 "The gen must be right, and we must be doing the barrier "
68 "in older generations.");
69 T heap_oop = oopDesc::load_heap_oop(p);
70 if (!oopDesc::is_null(heap_oop)) {
71 oop obj = oopDesc::decode_heap_oop_not_null(heap_oop);
72 if ((HeapWord*)obj < _boundary) {
73 assert(!_g->to()->is_in_reserved(obj), "Scanning field twice?");
74 // OK, we need to ensure that it is copied.
75 // We read the klass and mark in this order, so that we can reliably
76 // get the size of the object: if the mark we read is not a
77 // forwarding pointer, then the klass is valid: the klass is only
78 // overwritten with an overflow next pointer after the object is
79 // forwarded.
80 klassOop objK = obj->klass();
81 markOop m = obj->mark();
82 oop new_obj;
83 if (m->is_marked()) { // Contains forwarding pointer.
84 new_obj = ParNewGeneration::real_forwardee(obj);
85 oopDesc::encode_store_heap_oop_not_null(p, new_obj);
86 } else {
87 size_t obj_sz = obj->size_given_klass(objK->klass_part());
88 new_obj = _g->copy_to_survivor_space(_par_scan_state, obj, obj_sz, m);
89 oopDesc::encode_store_heap_oop_not_null(p, new_obj);
90 if (root_scan) {
91 // This may have pushed an object. If we have a root
92 // category with a lot of roots, can't let the queue get too
93 // full:
94 (void)_par_scan_state->trim_queues(10 * ParallelGCThreads);
95 }
96 }
97 if (gc_barrier) {
98 // Now call parent closure
99 par_do_barrier(p);
100 }
101 }
102 }
103 }
105 inline void ParScanWithBarrierClosure::do_oop_nv(oop* p) { ParScanClosure::do_oop_work(p, true, false); }
106 inline void ParScanWithBarrierClosure::do_oop_nv(narrowOop* p) { ParScanClosure::do_oop_work(p, true, false); }
108 inline void ParScanWithoutBarrierClosure::do_oop_nv(oop* p) { ParScanClosure::do_oop_work(p, false, false); }
109 inline void ParScanWithoutBarrierClosure::do_oop_nv(narrowOop* p) { ParScanClosure::do_oop_work(p, false, false); }
