1 /*
2 * Copyright (c) 2015, Red Hat, Inc. and/or its affiliates.
3 *
4 * This code is free software; you can redistribute it and/or modify it
5 * under the terms of the GNU General Public License version 2 only, as
6 * published by the Free Software Foundation.
7 *
8 * This code is distributed in the hope that it will be useful, but WITHOUT
9 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
10 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
11 * version 2 for more details (a copy is included in the LICENSE file that
12 * accompanied this code).
13 *
14 * You should have received a copy of the GNU General Public License version
15 * 2 along with this work; if not, write to the Free Software Foundation,
16 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
17 *
18 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
19 * or visit www.oracle.com if you need additional information or have any
20 * questions.
21 *
22 */
23
24 #ifndef SHARE_VM_GC_SHENANDOAH_SHENANDOAHCONCURRENTMARK_INLINE_HPP
25 #define SHARE_VM_GC_SHENANDOAH_SHENANDOAHCONCURRENTMARK_INLINE_HPP
26
27 #include "gc/shenandoah/brooksPointer.hpp"
28 #include "gc/shenandoah/shenandoahConcurrentMark.hpp"
29 #include "memory/iterator.inline.hpp"
30 #include "oops/oop.inline.hpp"
31 #include "runtime/prefetch.inline.hpp"
32
33 void ShenandoahMarkRefsClosure::do_oop(oop* p) {
34 // We piggy-back reference updating to the marking tasks.
35 #ifdef ASSERT
36 oop* old = p;
37 #endif
38 oop obj;
39 if (_update_refs) {
40 obj = _heap->maybe_update_oop_ref(p);
41 } else {
42 obj = oopDesc::load_heap_oop(p);
43 }
44 assert(obj == ShenandoahBarrierSet::resolve_oop_static(obj), "need to-space object here");
45
46 #ifdef ASSERT
47 if (ShenandoahTraceUpdates) {
48 if (p != old)
49 tty->print_cr("Update "PTR_FORMAT" => "PTR_FORMAT" to "PTR_FORMAT" => "PTR_FORMAT, p2i(p), p2i((HeapWord*) *p), p2i(old), p2i((HeapWord*) *old));
50 else
51 tty->print_cr("Not updating "PTR_FORMAT" => "PTR_FORMAT" to "PTR_FORMAT" => "PTR_FORMAT, p2i(p), p2i((HeapWord*) *p), p2i(old), p2i((HeapWord*) *old));
52 }
53 #endif
54
55 // NOTE: We used to assert the following here. This does not always work because
56 // a concurrent Java thread could change the the field after we updated it.
57 // oop obj = oopDesc::load_heap_oop(p);
58 // assert(oopDesc::bs()->resolve_oop(obj) == *p, "we just updated the referrer");
59 // assert(obj == NULL || ! _heap->heap_region_containing(obj)->is_dirty(), "must not point to dirty region");
60
61 // ShenandoahExtendedMarkObjsClosure cl(_heap->ref_processor(), _worker_id);
62 // ShenandoahMarkObjsClosure mocl(cl, _worker_id);
63
64 if (obj != NULL) {
65 if (_update_refs) {
66 Prefetch::write(obj, 128);
67 } else {
68 Prefetch::read(obj, 128);
69 }
70
71 #ifdef ASSERT
72 uint region_idx = _heap->heap_region_index_containing(obj);
73 ShenandoahHeapRegion* r = _heap->heap_regions()[region_idx];
74 assert(r->bottom() < (HeapWord*) obj && r->top() > (HeapWord*) obj, "object must be in region");
75 #endif
76
77 bool pushed = _queue->push(obj);
78 assert(pushed, "overflow queue should always succeed pushing");
79 }
80 }
81
82 void ShenandoahMarkObjsClosure::do_object(oop obj) {
83
84 assert(obj != NULL, "expect non-null object");
85
86 assert(obj == ShenandoahBarrierSet::resolve_oop_static_not_null(obj), "expect forwarded obj in queue");
87
88 #ifdef ASSERT
89 if (_heap->heap_region_containing(obj)->is_in_collection_set()) {
90 tty->print_cr("trying to mark obj: "PTR_FORMAT" (%s) in dirty region: ", p2i((HeapWord*) obj), BOOL_TO_STR(_heap->is_marked_current(obj)));
91 // _heap->heap_region_containing(obj)->print();
92 // _heap->print_heap_regions();
93 }
94 #endif
95 assert(_heap->cancelled_concgc()
96 || ! _heap->heap_region_containing(obj)->is_in_collection_set(),
97 "we don't want to mark objects in from-space");
98 assert(_heap->is_in(obj), "referenced objects must be in the heap. No?");
99 if (_heap->mark_current(obj)) {
100 #ifdef ASSERT
101 if (ShenandoahTraceConcurrentMarking) {
102 tty->print_cr("marked obj: "PTR_FORMAT, p2i((HeapWord*) obj));
103 }
104 #endif
105
106 // Calculate liveness of heap region containing object.
107 uint region_idx = _heap->heap_region_index_containing(obj);
108 #ifdef ASSERT
109 ShenandoahHeapRegion* r = _heap->heap_regions()[region_idx];
110 assert(r->bottom() < (HeapWord*) obj && r->top() > (HeapWord*) obj, "object must be in region");
111 #endif
112 _live_data[region_idx] += (obj->size() + BrooksPointer::BROOKS_POINTER_OBJ_SIZE) * HeapWordSize;
113 obj->oop_iterate(&_mark_refs);
114 }
115
116 #ifdef ASSERT
117 else {
118 if (ShenandoahTraceConcurrentMarking) {
119 tty->print_cr("failed to mark obj (already marked): "PTR_FORMAT, p2i((HeapWord*) obj));
120 }
121 assert(_heap->is_marked_current(obj), "make sure object is marked");
122 }
123 #endif
124 }
125
126 inline bool ShenandoahConcurrentMark::try_queue(SCMObjToScanQueue* q, ShenandoahMarkObjsClosure* cl) {
127 oop obj;
128 if (q->pop_local(obj)) {
129 assert(obj != NULL, "Can't mark null");
130 cl->do_object(obj);
131 return true;
132 } else if (q->pop_overflow(obj)) {
133 cl->do_object(obj);
134 return true;
135 } else {
136 return false;
137 }
138 }
139
140 inline bool ShenandoahConcurrentMark::try_to_steal(uint worker_id, ShenandoahMarkObjsClosure* cl, int *seed) {
141 oop obj;
142 if (task_queues()->steal(worker_id, seed, obj)) {
143 cl->do_object(obj);
144 return true;
145 } else
146 return false;
147 }
148
149 inline bool ShenandoahConcurrentMark:: try_draining_an_satb_buffer(uint worker_id) {
150 return drain_one_satb_buffer(worker_id);
151 }
152
153 #endif // SHARE_VM_GC_SHENANDOAH_SHENANDOAHCONCURRENTMARK_INLINE_HPP