1 /*
2 * Copyright (c) 2015, 2018, 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
24 #include "precompiled.hpp"
25 #include "gc/shared/gcHeapSummary.hpp"
26 #include "gc/shared/suspendibleThreadSet.hpp"
27 #include "gc/z/zCollectedHeap.hpp"
28 #include "gc/z/zGlobals.hpp"
29 #include "gc/z/zHeap.inline.hpp"
30 #include "gc/z/zNMethodTable.hpp"
31 #include "gc/z/zServiceability.hpp"
32 #include "gc/z/zStat.hpp"
33 #include "gc/z/zUtils.inline.hpp"
34 #include "runtime/mutexLocker.hpp"
35
36 ZCollectedHeap* ZCollectedHeap::heap() {
37 CollectedHeap* heap = Universe::heap();
38 assert(heap != NULL, "Uninitialized access to ZCollectedHeap::heap()");
39 assert(heap->kind() == CollectedHeap::Z, "Invalid name");
40 return (ZCollectedHeap*)heap;
41 }
42
43 ZCollectedHeap::ZCollectedHeap(ZCollectorPolicy* policy) :
44 _collector_policy(policy),
45 _soft_ref_policy(),
46 _barrier_set(),
47 _initialize(&_barrier_set),
48 _heap(),
49 _director(new ZDirector()),
50 _driver(new ZDriver()),
51 _stat(new ZStat()),
52 _runtime_workers() {}
53
54 CollectedHeap::Name ZCollectedHeap::kind() const {
55 return CollectedHeap::Z;
56 }
57
58 const char* ZCollectedHeap::name() const {
59 return ZGCName;
60 }
61
62 jint ZCollectedHeap::initialize() {
63 if (!_heap.is_initialized()) {
64 return JNI_ENOMEM;
65 }
66
67 initialize_reserved_region((HeapWord*)ZAddressReservedStart(),
68 (HeapWord*)ZAddressReservedEnd());
69
70 // ZGC fixes up nmethods lazily, so the assumption that nmethods will
71 // look good after GC safepoints, does not hold.
72 Universe::disable_verify_subset(Universe::Verify_CodeCacheOops);
73
74 return JNI_OK;
75 }
76
77 void ZCollectedHeap::initialize_serviceability() {
78 _heap.serviceability_initialize();
79 }
80
81 void ZCollectedHeap::stop() {
82 _director->stop();
83 _driver->stop();
84 _stat->stop();
85 }
86
87 CollectorPolicy* ZCollectedHeap::collector_policy() const {
88 return _collector_policy;
89 }
90
91 SoftRefPolicy* ZCollectedHeap::soft_ref_policy() {
92 return &_soft_ref_policy;
93 }
94
95 size_t ZCollectedHeap::max_capacity() const {
96 return _heap.max_capacity();
97 }
98
99 size_t ZCollectedHeap::capacity() const {
100 return _heap.capacity();
101 }
102
103 size_t ZCollectedHeap::used() const {
104 return _heap.used();
105 }
106
107 bool ZCollectedHeap::is_maximal_no_gc() const {
108 // Not supported
109 ShouldNotReachHere();
110 return false;
111 }
112
113 bool ZCollectedHeap::is_scavengable(oop obj) {
114 return false;
115 }
116
117 bool ZCollectedHeap::is_in(const void* p) const {
118 return is_in_reserved(p) && _heap.is_in((uintptr_t)p);
119 }
120
121 bool ZCollectedHeap::is_in_closed_subset(const void* p) const {
122 return is_in(p);
123 }
124
125 void ZCollectedHeap::fill_with_dummy_object(HeapWord* start, HeapWord* end, bool zap) {
126 // Does nothing, not a parsable heap
127 }
128
129 HeapWord* ZCollectedHeap::allocate_new_tlab(size_t min_size, size_t requested_size, size_t* actual_size) {
130 const size_t size_in_bytes = ZUtils::words_to_bytes(align_object_size(requested_size));
131 const uintptr_t addr = _heap.alloc_tlab(size_in_bytes);
132
133 if (addr != 0) {
134 *actual_size = requested_size;
135 }
136
137 return (HeapWord*)addr;
138 }
139
140 HeapWord* ZCollectedHeap::mem_allocate(size_t size, bool* gc_overhead_limit_was_exceeded) {
141 const size_t size_in_bytes = ZUtils::words_to_bytes(align_object_size(size));
142 return (HeapWord*)_heap.alloc_object(size_in_bytes);
143 }
144
145 MetaWord* ZCollectedHeap::satisfy_failed_metadata_allocation(ClassLoaderData* loader_data,
146 size_t size,
147 Metaspace::MetadataType mdtype) {
148 MetaWord* result;
149
150 // Start asynchronous GC
151 collect(GCCause::_metadata_GC_threshold);
152
153 // Expand and retry allocation
154 result = loader_data->metaspace_non_null()->expand_and_allocate(size, mdtype);
155 if (result != NULL) {
156 return result;
157 }
158
159 // Start synchronous GC
160 collect(GCCause::_metadata_GC_clear_soft_refs);
161
162 // Retry allocation
163 result = loader_data->metaspace_non_null()->allocate(size, mdtype);
164 if (result != NULL) {
165 return result;
166 }
167
168 // Expand and retry allocation
169 result = loader_data->metaspace_non_null()->expand_and_allocate(size, mdtype);
170 if (result != NULL) {
171 return result;
172 }
173
174 // Out of memory
175 return NULL;
176 }
177
178 void ZCollectedHeap::collect(GCCause::Cause cause) {
179 _driver->collect(cause);
180 }
181
182 void ZCollectedHeap::collect_as_vm_thread(GCCause::Cause cause) {
183 // These collection requests are ignored since ZGC can't run a synchronous
184 // GC cycle from within the VM thread. This is considered benign, since the
185 // only GC causes coming in here should be heap dumper and heap inspector.
186 // However, neither the heap dumper nor the heap inspector really need a GC
187 // to happen, but the result of their heap iterations might in that case be
188 // less accurate since they might include objects that would otherwise have
189 // been collected by a GC.
190 assert(Thread::current()->is_VM_thread(), "Should be the VM thread");
191 guarantee(cause == GCCause::_heap_dump ||
192 cause == GCCause::_heap_inspection, "Invalid cause");
193 }
194
195 void ZCollectedHeap::do_full_collection(bool clear_all_soft_refs) {
196 // Not supported
197 ShouldNotReachHere();
198 }
199
200 bool ZCollectedHeap::supports_tlab_allocation() const {
201 return true;
202 }
203
204 size_t ZCollectedHeap::tlab_capacity(Thread* ignored) const {
205 return _heap.tlab_capacity();
206 }
207
208 size_t ZCollectedHeap::tlab_used(Thread* ignored) const {
209 return _heap.tlab_used();
210 }
211
212 size_t ZCollectedHeap::max_tlab_size() const {
213 return _heap.max_tlab_size();
214 }
215
216 size_t ZCollectedHeap::unsafe_max_tlab_alloc(Thread* ignored) const {
217 return _heap.unsafe_max_tlab_alloc();
218 }
219
220 bool ZCollectedHeap::can_elide_tlab_store_barriers() const {
221 return false;
222 }
223
224 bool ZCollectedHeap::can_elide_initializing_store_barrier(oop new_obj) {
225 // Not supported
226 ShouldNotReachHere();
227 return true;
228 }
229
230 bool ZCollectedHeap::card_mark_must_follow_store() const {
231 // Not supported
232 ShouldNotReachHere();
233 return false;
234 }
235
236 GrowableArray<GCMemoryManager*> ZCollectedHeap::memory_managers() {
237 return GrowableArray<GCMemoryManager*>(1, 1, _heap.serviceability_memory_manager());
238 }
239
240 GrowableArray<MemoryPool*> ZCollectedHeap::memory_pools() {
241 return GrowableArray<MemoryPool*>(1, 1, _heap.serviceability_memory_pool());
242 }
243
244 void ZCollectedHeap::object_iterate(ObjectClosure* cl) {
245 _heap.object_iterate(cl, true /* visit_referents */);
246 }
247
248 void ZCollectedHeap::safe_object_iterate(ObjectClosure* cl) {
249 _heap.object_iterate(cl, true /* visit_referents */);
250 }
251
252 HeapWord* ZCollectedHeap::block_start(const void* addr) const {
253 return (HeapWord*)_heap.block_start((uintptr_t)addr);
254 }
255
256 size_t ZCollectedHeap::block_size(const HeapWord* addr) const {
257 size_t size_in_bytes = _heap.block_size((uintptr_t)addr);
258 return ZUtils::bytes_to_words(size_in_bytes);
259 }
260
261 bool ZCollectedHeap::block_is_obj(const HeapWord* addr) const {
262 return _heap.block_is_obj((uintptr_t)addr);
263 }
264
265 void ZCollectedHeap::register_nmethod(nmethod* nm) {
266 assert_locked_or_safepoint(CodeCache_lock);
267 ZNMethodTable::register_nmethod(nm);
268 }
269
270 void ZCollectedHeap::unregister_nmethod(nmethod* nm) {
271 assert_locked_or_safepoint(CodeCache_lock);
272 ZNMethodTable::unregister_nmethod(nm);
273 }
274
275 void ZCollectedHeap::verify_nmethod(nmethod* nm) {
276 // Does nothing
277 }
278
279 WorkGang* ZCollectedHeap::get_safepoint_workers() {
280 return _runtime_workers.workers();
281 }
282
283 jlong ZCollectedHeap::millis_since_last_gc() {
284 return ZStatCycle::time_since_last() / MILLIUNITS;
285 }
286
287 void ZCollectedHeap::gc_threads_do(ThreadClosure* tc) const {
288 tc->do_thread(_director);
289 tc->do_thread(_driver);
290 tc->do_thread(_stat);
291 _heap.worker_threads_do(tc);
292 _runtime_workers.threads_do(tc);
293 }
294
295 VirtualSpaceSummary ZCollectedHeap::create_heap_space_summary() {
296 const size_t capacity_in_words = capacity() / HeapWordSize;
297 const size_t max_capacity_in_words = max_capacity() / HeapWordSize;
298 return VirtualSpaceSummary(reserved_region().start(),
299 reserved_region().start() + capacity_in_words,
300 reserved_region().start() + max_capacity_in_words);
301 }
302
303 void ZCollectedHeap::safepoint_synchronize_begin() {
304 SuspendibleThreadSet::synchronize();
305 }
306
307 void ZCollectedHeap::safepoint_synchronize_end() {
308 SuspendibleThreadSet::desynchronize();
309 }
310
311 void ZCollectedHeap::prepare_for_verify() {
312 // Does nothing
313 }
314
315 void ZCollectedHeap::print_on(outputStream* st) const {
316 _heap.print_on(st);
317 }
318
319 void ZCollectedHeap::print_on_error(outputStream* st) const {
320 CollectedHeap::print_on_error(st);
321
322 st->print_cr("Address Space");
323 st->print_cr( " Start: " PTR_FORMAT, ZAddressSpaceStart);
324 st->print_cr( " End: " PTR_FORMAT, ZAddressSpaceEnd);
325 st->print_cr( " Size: " SIZE_FORMAT_W(-15) " (" PTR_FORMAT ")", ZAddressSpaceSize, ZAddressSpaceSize);
326 st->print_cr( "Heap");
327 st->print_cr( " GlobalPhase: %u", ZGlobalPhase);
328 st->print_cr( " GlobalSeqNum: %u", ZGlobalSeqNum);
329 st->print_cr( " Offset Max: " SIZE_FORMAT_W(-15) " (" PTR_FORMAT ")", ZAddressOffsetMax, ZAddressOffsetMax);
330 st->print_cr( " Page Size Small: " SIZE_FORMAT_W(-15) " (" PTR_FORMAT ")", ZPageSizeSmall, ZPageSizeSmall);
331 st->print_cr( " Page Size Medium: " SIZE_FORMAT_W(-15) " (" PTR_FORMAT ")", ZPageSizeMedium, ZPageSizeMedium);
332 st->print_cr( "Metadata Bits");
333 st->print_cr( " Good: " PTR_FORMAT, ZAddressGoodMask);
334 st->print_cr( " Bad: " PTR_FORMAT, ZAddressBadMask);
335 st->print_cr( " WeakBad: " PTR_FORMAT, ZAddressWeakBadMask);
336 st->print_cr( " Marked: " PTR_FORMAT, ZAddressMetadataMarked);
337 st->print_cr( " Remapped: " PTR_FORMAT, ZAddressMetadataRemapped);
338 }
339
340 void ZCollectedHeap::print_extended_on(outputStream* st) const {
341 _heap.print_extended_on(st);
342 }
343
344 void ZCollectedHeap::print_gc_threads_on(outputStream* st) const {
345 _director->print_on(st);
346 st->cr();
347 _driver->print_on(st);
348 st->cr();
349 _stat->print_on(st);
350 st->cr();
351 _heap.print_worker_threads_on(st);
352 _runtime_workers.print_threads_on(st);
353 }
354
355 void ZCollectedHeap::print_tracing_info() const {
356 // Does nothing
357 }
358
359 void ZCollectedHeap::verify(VerifyOption option /* ignored */) {
360 _heap.verify();
361 }
362
363 bool ZCollectedHeap::is_oop(oop object) const {
364 return CollectedHeap::is_oop(object) && _heap.is_oop(object);
365 }