Mon, 08 Dec 2014 18:57:33 +0100
8067655: Clean up G1 remembered set oop iteration
Summary: Pass on the static type G1ParPushHeapRSClosure to allow oop_iterate devirtualization
Reviewed-by: jmasa, kbarrett
1 /*
2 * Copyright (c) 2001, 2014, 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 #ifndef SHARE_VM_GC_IMPLEMENTATION_G1_G1OOPCLOSURES_INLINE_HPP
26 #define SHARE_VM_GC_IMPLEMENTATION_G1_G1OOPCLOSURES_INLINE_HPP
28 #include "gc_implementation/g1/concurrentMark.inline.hpp"
29 #include "gc_implementation/g1/g1CollectedHeap.hpp"
30 #include "gc_implementation/g1/g1OopClosures.hpp"
31 #include "gc_implementation/g1/g1ParScanThreadState.inline.hpp"
32 #include "gc_implementation/g1/g1RemSet.hpp"
33 #include "gc_implementation/g1/g1RemSet.inline.hpp"
34 #include "gc_implementation/g1/heapRegionRemSet.hpp"
35 #include "memory/iterator.inline.hpp"
36 #include "runtime/prefetch.inline.hpp"
38 /*
39 * This really ought to be an inline function, but apparently the C++
40 * compiler sometimes sees fit to ignore inline declarations. Sigh.
41 */
43 template <class T>
44 inline void FilterIntoCSClosure::do_oop_nv(T* p) {
45 T heap_oop = oopDesc::load_heap_oop(p);
46 if (!oopDesc::is_null(heap_oop) &&
47 _g1->is_in_cset_or_humongous(oopDesc::decode_heap_oop_not_null(heap_oop))) {
48 _oc->do_oop(p);
49 }
50 }
52 template <class T>
53 inline void FilterOutOfRegionClosure::do_oop_nv(T* p) {
54 T heap_oop = oopDesc::load_heap_oop(p);
55 if (!oopDesc::is_null(heap_oop)) {
56 HeapWord* obj_hw = (HeapWord*)oopDesc::decode_heap_oop_not_null(heap_oop);
57 if (obj_hw < _r_bottom || obj_hw >= _r_end) {
58 _oc->do_oop(p);
59 }
60 }
61 }
63 // This closure is applied to the fields of the objects that have just been copied.
64 template <class T>
65 inline void G1ParScanClosure::do_oop_nv(T* p) {
66 T heap_oop = oopDesc::load_heap_oop(p);
68 if (!oopDesc::is_null(heap_oop)) {
69 oop obj = oopDesc::decode_heap_oop_not_null(heap_oop);
70 G1CollectedHeap::in_cset_state_t state = _g1->in_cset_state(obj);
71 if (state == G1CollectedHeap::InCSet) {
72 // We're not going to even bother checking whether the object is
73 // already forwarded or not, as this usually causes an immediate
74 // stall. We'll try to prefetch the object (for write, given that
75 // we might need to install the forwarding reference) and we'll
76 // get back to it when pop it from the queue
77 Prefetch::write(obj->mark_addr(), 0);
78 Prefetch::read(obj->mark_addr(), (HeapWordSize*2));
80 // slightly paranoid test; I'm trying to catch potential
81 // problems before we go into push_on_queue to know where the
82 // problem is coming from
83 assert((obj == oopDesc::load_decode_heap_oop(p)) ||
84 (obj->is_forwarded() &&
85 obj->forwardee() == oopDesc::load_decode_heap_oop(p)),
86 "p should still be pointing to obj or to its forwardee");
88 _par_scan_state->push_on_queue(p);
89 } else {
90 if (state == G1CollectedHeap::IsHumongous) {
91 _g1->set_humongous_is_live(obj);
92 }
93 _par_scan_state->update_rs(_from, p, _worker_id);
94 }
95 }
96 }
98 template <class T>
99 inline void G1ParPushHeapRSClosure::do_oop_nv(T* p) {
100 T heap_oop = oopDesc::load_heap_oop(p);
102 if (!oopDesc::is_null(heap_oop)) {
103 oop obj = oopDesc::decode_heap_oop_not_null(heap_oop);
104 if (_g1->is_in_cset_or_humongous(obj)) {
105 Prefetch::write(obj->mark_addr(), 0);
106 Prefetch::read(obj->mark_addr(), (HeapWordSize*2));
108 // Place on the references queue
109 _par_scan_state->push_on_queue(p);
110 } else {
111 assert(!_g1->obj_in_cs(obj), "checking");
112 }
113 }
114 }
116 template <class T>
117 inline void G1CMOopClosure::do_oop_nv(T* p) {
118 oop obj = oopDesc::load_decode_heap_oop(p);
119 if (_cm->verbose_high()) {
120 gclog_or_tty->print_cr("[%u] we're looking at location "
121 "*"PTR_FORMAT" = "PTR_FORMAT,
122 _task->worker_id(), p2i(p), p2i((void*) obj));
123 }
124 _task->deal_with_reference(obj);
125 }
127 template <class T>
128 inline void G1RootRegionScanClosure::do_oop_nv(T* p) {
129 T heap_oop = oopDesc::load_heap_oop(p);
130 if (!oopDesc::is_null(heap_oop)) {
131 oop obj = oopDesc::decode_heap_oop_not_null(heap_oop);
132 HeapRegion* hr = _g1h->heap_region_containing((HeapWord*) obj);
133 _cm->grayRoot(obj, obj->size(), _worker_id, hr);
134 }
135 }
137 template <class T>
138 inline void G1Mux2Closure::do_oop_nv(T* p) {
139 // Apply first closure; then apply the second.
140 _c1->do_oop(p);
141 _c2->do_oop(p);
142 }
144 template <class T>
145 inline void G1TriggerClosure::do_oop_nv(T* p) {
146 // Record that this closure was actually applied (triggered).
147 _triggered = true;
148 }
150 template <class T>
151 inline void G1InvokeIfNotTriggeredClosure::do_oop_nv(T* p) {
152 if (!_trigger_cl->triggered()) {
153 _oop_cl->do_oop(p);
154 }
155 }
157 template <class T>
158 inline void G1UpdateRSOrPushRefOopClosure::do_oop_nv(T* p) {
159 oop obj = oopDesc::load_decode_heap_oop(p);
160 if (obj == NULL) {
161 return;
162 }
163 #ifdef ASSERT
164 // can't do because of races
165 // assert(obj == NULL || obj->is_oop(), "expected an oop");
167 // Do the safe subset of is_oop
168 #ifdef CHECK_UNHANDLED_OOPS
169 oopDesc* o = obj.obj();
170 #else
171 oopDesc* o = obj;
172 #endif // CHECK_UNHANDLED_OOPS
173 assert((intptr_t)o % MinObjAlignmentInBytes == 0, "not oop aligned");
174 assert(Universe::heap()->is_in_reserved(obj), "must be in heap");
175 #endif // ASSERT
177 assert(_from != NULL, "from region must be non-NULL");
178 assert(_from->is_in_reserved(p), "p is not in from");
180 HeapRegion* to = _g1->heap_region_containing(obj);
181 if (_from == to) {
182 // Normally this closure should only be called with cross-region references.
183 // But since Java threads are manipulating the references concurrently and we
184 // reload the values things may have changed.
185 return;
186 }
187 // The _record_refs_into_cset flag is true during the RSet
188 // updating part of an evacuation pause. It is false at all
189 // other times:
190 // * rebuilding the remembered sets after a full GC
191 // * during concurrent refinement.
192 // * updating the remembered sets of regions in the collection
193 // set in the event of an evacuation failure (when deferred
194 // updates are enabled).
196 if (_record_refs_into_cset && to->in_collection_set()) {
197 // We are recording references that point into the collection
198 // set and this particular reference does exactly that...
199 // If the referenced object has already been forwarded
200 // to itself, we are handling an evacuation failure and
201 // we have already visited/tried to copy this object
202 // there is no need to retry.
203 if (!self_forwarded(obj)) {
204 assert(_push_ref_cl != NULL, "should not be null");
205 // Push the reference in the refs queue of the G1ParScanThreadState
206 // instance for this worker thread.
207 _push_ref_cl->do_oop(p);
208 }
210 // Deferred updates to the CSet are either discarded (in the normal case),
211 // or processed (if an evacuation failure occurs) at the end
212 // of the collection.
213 // See G1RemSet::cleanup_after_oops_into_collection_set_do().
214 } else {
215 // We either don't care about pushing references that point into the
216 // collection set (i.e. we're not during an evacuation pause) _or_
217 // the reference doesn't point into the collection set. Either way
218 // we add the reference directly to the RSet of the region containing
219 // the referenced object.
220 assert(to->rem_set() != NULL, "Need per-region 'into' remsets.");
221 to->rem_set()->add_reference(p, _worker_i);
222 }
223 }
225 #endif // SHARE_VM_GC_IMPLEMENTATION_G1_G1OOPCLOSURES_INLINE_HPP