Fri, 17 May 2013 11:57:05 +0200
8014277: Remove ObjectClosure as base class for BoolObjectClosure
Reviewed-by: brutisso, tschatzl
1 /*
2 * Copyright (c) 2002, 2012, 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.
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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.
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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
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23 */
25 #include "precompiled.hpp"
26 #include "gc_implementation/parallelScavenge/parallelScavengeHeap.hpp"
27 #include "gc_implementation/parallelScavenge/psOldGen.hpp"
28 #include "gc_implementation/parallelScavenge/psPromotionManager.inline.hpp"
29 #include "gc_implementation/parallelScavenge/psScavenge.inline.hpp"
30 #include "gc_implementation/shared/mutableSpace.hpp"
31 #include "memory/memRegion.hpp"
32 #include "oops/oop.inline.hpp"
33 #include "oops/oop.psgc.inline.hpp"
35 PSPromotionManager** PSPromotionManager::_manager_array = NULL;
36 OopStarTaskQueueSet* PSPromotionManager::_stack_array_depth = NULL;
37 PSOldGen* PSPromotionManager::_old_gen = NULL;
38 MutableSpace* PSPromotionManager::_young_space = NULL;
40 void PSPromotionManager::initialize() {
41 ParallelScavengeHeap* heap = (ParallelScavengeHeap*)Universe::heap();
42 assert(heap->kind() == CollectedHeap::ParallelScavengeHeap, "Sanity");
44 _old_gen = heap->old_gen();
45 _young_space = heap->young_gen()->to_space();
47 assert(_manager_array == NULL, "Attempt to initialize twice");
48 _manager_array = NEW_C_HEAP_ARRAY(PSPromotionManager*, ParallelGCThreads+1, mtGC);
49 guarantee(_manager_array != NULL, "Could not initialize promotion manager");
51 _stack_array_depth = new OopStarTaskQueueSet(ParallelGCThreads);
52 guarantee(_stack_array_depth != NULL, "Cound not initialize promotion manager");
54 // Create and register the PSPromotionManager(s) for the worker threads.
55 for(uint i=0; i<ParallelGCThreads; i++) {
56 _manager_array[i] = new PSPromotionManager();
57 guarantee(_manager_array[i] != NULL, "Could not create PSPromotionManager");
58 stack_array_depth()->register_queue(i, _manager_array[i]->claimed_stack_depth());
59 }
61 // The VMThread gets its own PSPromotionManager, which is not available
62 // for work stealing.
63 _manager_array[ParallelGCThreads] = new PSPromotionManager();
64 guarantee(_manager_array[ParallelGCThreads] != NULL, "Could not create PSPromotionManager");
65 }
67 PSPromotionManager* PSPromotionManager::gc_thread_promotion_manager(int index) {
68 assert(index >= 0 && index < (int)ParallelGCThreads, "index out of range");
69 assert(_manager_array != NULL, "Sanity");
70 return _manager_array[index];
71 }
73 PSPromotionManager* PSPromotionManager::vm_thread_promotion_manager() {
74 assert(_manager_array != NULL, "Sanity");
75 return _manager_array[ParallelGCThreads];
76 }
78 void PSPromotionManager::pre_scavenge() {
79 ParallelScavengeHeap* heap = (ParallelScavengeHeap*)Universe::heap();
80 assert(heap->kind() == CollectedHeap::ParallelScavengeHeap, "Sanity");
82 _young_space = heap->young_gen()->to_space();
84 for(uint i=0; i<ParallelGCThreads+1; i++) {
85 manager_array(i)->reset();
86 }
87 }
89 void PSPromotionManager::post_scavenge() {
90 TASKQUEUE_STATS_ONLY(if (PrintGCDetails && ParallelGCVerbose) print_stats());
91 for (uint i = 0; i < ParallelGCThreads + 1; i++) {
92 PSPromotionManager* manager = manager_array(i);
93 assert(manager->claimed_stack_depth()->is_empty(), "should be empty");
94 manager->flush_labs();
95 }
96 }
98 #if TASKQUEUE_STATS
99 void
100 PSPromotionManager::print_taskqueue_stats(uint i) const {
101 tty->print("%3u ", i);
102 _claimed_stack_depth.stats.print();
103 tty->cr();
104 }
106 void
107 PSPromotionManager::print_local_stats(uint i) const {
108 #define FMT " " SIZE_FORMAT_W(10)
109 tty->print_cr("%3u" FMT FMT FMT FMT, i, _masked_pushes, _masked_steals,
110 _arrays_chunked, _array_chunks_processed);
111 #undef FMT
112 }
114 static const char* const pm_stats_hdr[] = {
115 " --------masked------- arrays array",
116 "thr push steal chunked chunks",
117 "--- ---------- ---------- ---------- ----------"
118 };
120 void
121 PSPromotionManager::print_stats() {
122 tty->print_cr("== GC Tasks Stats, GC %3d",
123 Universe::heap()->total_collections());
125 tty->print("thr "); TaskQueueStats::print_header(1); tty->cr();
126 tty->print("--- "); TaskQueueStats::print_header(2); tty->cr();
127 for (uint i = 0; i < ParallelGCThreads + 1; ++i) {
128 manager_array(i)->print_taskqueue_stats(i);
129 }
131 const uint hlines = sizeof(pm_stats_hdr) / sizeof(pm_stats_hdr[0]);
132 for (uint i = 0; i < hlines; ++i) tty->print_cr(pm_stats_hdr[i]);
133 for (uint i = 0; i < ParallelGCThreads + 1; ++i) {
134 manager_array(i)->print_local_stats(i);
135 }
136 }
138 void
139 PSPromotionManager::reset_stats() {
140 claimed_stack_depth()->stats.reset();
141 _masked_pushes = _masked_steals = 0;
142 _arrays_chunked = _array_chunks_processed = 0;
143 }
144 #endif // TASKQUEUE_STATS
146 PSPromotionManager::PSPromotionManager() {
147 ParallelScavengeHeap* heap = (ParallelScavengeHeap*)Universe::heap();
148 assert(heap->kind() == CollectedHeap::ParallelScavengeHeap, "Sanity");
150 // We set the old lab's start array.
151 _old_lab.set_start_array(old_gen()->start_array());
153 uint queue_size;
154 claimed_stack_depth()->initialize();
155 queue_size = claimed_stack_depth()->max_elems();
157 _totally_drain = (ParallelGCThreads == 1) || (GCDrainStackTargetSize == 0);
158 if (_totally_drain) {
159 _target_stack_size = 0;
160 } else {
161 // don't let the target stack size to be more than 1/4 of the entries
162 _target_stack_size = (uint) MIN2((uint) GCDrainStackTargetSize,
163 (uint) (queue_size / 4));
164 }
166 _array_chunk_size = ParGCArrayScanChunk;
167 // let's choose 1.5x the chunk size
168 _min_array_size_for_chunking = 3 * _array_chunk_size / 2;
170 reset();
171 }
173 void PSPromotionManager::reset() {
174 assert(stacks_empty(), "reset of non-empty stack");
176 // We need to get an assert in here to make sure the labs are always flushed.
178 ParallelScavengeHeap* heap = (ParallelScavengeHeap*)Universe::heap();
179 assert(heap->kind() == CollectedHeap::ParallelScavengeHeap, "Sanity");
181 // Do not prefill the LAB's, save heap wastage!
182 HeapWord* lab_base = young_space()->top();
183 _young_lab.initialize(MemRegion(lab_base, (size_t)0));
184 _young_gen_is_full = false;
186 lab_base = old_gen()->object_space()->top();
187 _old_lab.initialize(MemRegion(lab_base, (size_t)0));
188 _old_gen_is_full = false;
190 TASKQUEUE_STATS_ONLY(reset_stats());
191 }
194 void PSPromotionManager::drain_stacks_depth(bool totally_drain) {
195 totally_drain = totally_drain || _totally_drain;
197 #ifdef ASSERT
198 ParallelScavengeHeap* heap = (ParallelScavengeHeap*)Universe::heap();
199 assert(heap->kind() == CollectedHeap::ParallelScavengeHeap, "Sanity");
200 MutableSpace* to_space = heap->young_gen()->to_space();
201 MutableSpace* old_space = heap->old_gen()->object_space();
202 #endif /* ASSERT */
204 OopStarTaskQueue* const tq = claimed_stack_depth();
205 do {
206 StarTask p;
208 // Drain overflow stack first, so other threads can steal from
209 // claimed stack while we work.
210 while (tq->pop_overflow(p)) {
211 process_popped_location_depth(p);
212 }
214 if (totally_drain) {
215 while (tq->pop_local(p)) {
216 process_popped_location_depth(p);
217 }
218 } else {
219 while (tq->size() > _target_stack_size && tq->pop_local(p)) {
220 process_popped_location_depth(p);
221 }
222 }
223 } while (totally_drain && !tq->taskqueue_empty() || !tq->overflow_empty());
225 assert(!totally_drain || tq->taskqueue_empty(), "Sanity");
226 assert(totally_drain || tq->size() <= _target_stack_size, "Sanity");
227 assert(tq->overflow_empty(), "Sanity");
228 }
230 void PSPromotionManager::flush_labs() {
231 assert(stacks_empty(), "Attempt to flush lab with live stack");
233 // If either promotion lab fills up, we can flush the
234 // lab but not refill it, so check first.
235 assert(!_young_lab.is_flushed() || _young_gen_is_full, "Sanity");
236 if (!_young_lab.is_flushed())
237 _young_lab.flush();
239 assert(!_old_lab.is_flushed() || _old_gen_is_full, "Sanity");
240 if (!_old_lab.is_flushed())
241 _old_lab.flush();
243 // Let PSScavenge know if we overflowed
244 if (_young_gen_is_full) {
245 PSScavenge::set_survivor_overflow(true);
246 }
247 }
249 template <class T> void PSPromotionManager::process_array_chunk_work(
250 oop obj,
251 int start, int end) {
252 assert(start <= end, "invariant");
253 T* const base = (T*)objArrayOop(obj)->base();
254 T* p = base + start;
255 T* const chunk_end = base + end;
256 while (p < chunk_end) {
257 if (PSScavenge::should_scavenge(p)) {
258 claim_or_forward_depth(p);
259 }
260 ++p;
261 }
262 }
264 void PSPromotionManager::process_array_chunk(oop old) {
265 assert(PSChunkLargeArrays, "invariant");
266 assert(old->is_objArray(), "invariant");
267 assert(old->is_forwarded(), "invariant");
269 TASKQUEUE_STATS_ONLY(++_array_chunks_processed);
271 oop const obj = old->forwardee();
273 int start;
274 int const end = arrayOop(old)->length();
275 if (end > (int) _min_array_size_for_chunking) {
276 // we'll chunk more
277 start = end - _array_chunk_size;
278 assert(start > 0, "invariant");
279 arrayOop(old)->set_length(start);
280 push_depth(mask_chunked_array_oop(old));
281 TASKQUEUE_STATS_ONLY(++_masked_pushes);
282 } else {
283 // this is the final chunk for this array
284 start = 0;
285 int const actual_length = arrayOop(obj)->length();
286 arrayOop(old)->set_length(actual_length);
287 }
289 if (UseCompressedOops) {
290 process_array_chunk_work<narrowOop>(obj, start, end);
291 } else {
292 process_array_chunk_work<oop>(obj, start, end);
293 }
294 }
296 oop PSPromotionManager::oop_promotion_failed(oop obj, markOop obj_mark) {
297 assert(_old_gen_is_full || PromotionFailureALot, "Sanity");
299 // Attempt to CAS in the header.
300 // This tests if the header is still the same as when
301 // this started. If it is the same (i.e., no forwarding
302 // pointer has been installed), then this thread owns
303 // it.
304 if (obj->cas_forward_to(obj, obj_mark)) {
305 // We won any races, we "own" this object.
306 assert(obj == obj->forwardee(), "Sanity");
308 obj->push_contents(this);
310 // Save the mark if needed
311 PSScavenge::oop_promotion_failed(obj, obj_mark);
312 } else {
313 // We lost, someone else "owns" this object
314 guarantee(obj->is_forwarded(), "Object must be forwarded if the cas failed.");
316 // No unallocation to worry about.
317 obj = obj->forwardee();
318 }
320 #ifndef PRODUCT
321 if (TraceScavenge) {
322 gclog_or_tty->print_cr("{%s %s 0x%x (%d)}",
323 "promotion-failure",
324 obj->klass()->internal_name(),
325 obj, obj->size());
327 }
328 #endif
330 return obj;
331 }