1 /*
   2  * Copyright (c) 2015, 2019, 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/zNMethod.hpp"
  31 #include "gc/z/zServiceability.hpp"
  32 #include "gc/z/zStat.hpp"
  33 #include "gc/z/zUtils.inline.hpp"
  34 #include "memory/universe.hpp"
  35 #include "runtime/mutexLocker.hpp"
  36 
  37 ZCollectedHeap* ZCollectedHeap::heap() {
  38   CollectedHeap* heap = Universe::heap();
  39   assert(heap != NULL, "Uninitialized access to ZCollectedHeap::heap()");
  40   assert(heap->kind() == CollectedHeap::Z, "Invalid name");
  41   return (ZCollectedHeap*)heap;
  42 }
  43 
  44 ZCollectedHeap::ZCollectedHeap() :
  45     _soft_ref_policy(),
  46     _barrier_set(),
  47     _initialize(&_barrier_set),
  48     _heap(),
  49     _director(new ZDirector()),
  50     _driver(new ZDriver()),
  51     _uncommitter(new ZUncommitter()),
  52     _stat(new ZStat()),
  53     _runtime_workers() {}
  54 
  55 CollectedHeap::Name ZCollectedHeap::kind() const {
  56   return CollectedHeap::Z;
  57 }
  58 
  59 const char* ZCollectedHeap::name() const {
  60   return ZName;
  61 }
  62 
  63 jint ZCollectedHeap::initialize() {
  64   if (!_heap.is_initialized()) {
  65     return JNI_ENOMEM;
  66   }
  67 
  68   initialize_reserved_region((HeapWord*)ZAddressReservedStart,
  69                              (HeapWord*)ZAddressReservedEnd);
  70 
  71   return JNI_OK;
  72 }
  73 
  74 void ZCollectedHeap::initialize_serviceability() {
  75   _heap.serviceability_initialize();
  76 }
  77 
  78 void ZCollectedHeap::stop() {
  79   _director->stop();
  80   _driver->stop();
  81   _uncommitter->stop();
  82   _stat->stop();
  83 }
  84 
  85 SoftRefPolicy* ZCollectedHeap::soft_ref_policy() {
  86   return &_soft_ref_policy;
  87 }
  88 
  89 size_t ZCollectedHeap::max_capacity() const {
  90   return _heap.max_capacity();
  91 }
  92 
  93 size_t ZCollectedHeap::capacity() const {
  94   return _heap.capacity();
  95 }
  96 
  97 size_t ZCollectedHeap::used() const {
  98   return _heap.used();
  99 }
 100 
 101 size_t ZCollectedHeap::unused() const {
 102   return _heap.unused();
 103 }
 104 
 105 bool ZCollectedHeap::is_maximal_no_gc() const {
 106   // Not supported
 107   ShouldNotReachHere();
 108   return false;
 109 }
 110 
 111 bool ZCollectedHeap::is_in(const void* p) const {
 112   return _heap.is_in((uintptr_t)p);
 113 }
 114 
 115 uint32_t ZCollectedHeap::hash_oop(oop obj) const {
 116   return _heap.hash_oop(obj);
 117 }
 118 
 119 HeapWord* ZCollectedHeap::allocate_new_tlab(size_t min_size, size_t requested_size, size_t* actual_size) {
 120   const size_t size_in_bytes = ZUtils::words_to_bytes(align_object_size(requested_size));
 121   const uintptr_t addr = _heap.alloc_tlab(size_in_bytes);
 122 
 123   if (addr != 0) {
 124     *actual_size = requested_size;
 125   }
 126 
 127   return (HeapWord*)addr;
 128 }
 129 
 130 HeapWord* ZCollectedHeap::mem_allocate(size_t size, bool* gc_overhead_limit_was_exceeded) {
 131   const size_t size_in_bytes = ZUtils::words_to_bytes(align_object_size(size));
 132   return (HeapWord*)_heap.alloc_object(size_in_bytes);
 133 }
 134 
 135 MetaWord* ZCollectedHeap::satisfy_failed_metadata_allocation(ClassLoaderData* loader_data,
 136                                                              size_t size,
 137                                                              Metaspace::MetadataType mdtype) {
 138   MetaWord* result;
 139 
 140   // Start asynchronous GC
 141   collect(GCCause::_metadata_GC_threshold);
 142 
 143   // Expand and retry allocation
 144   result = loader_data->metaspace_non_null()->expand_and_allocate(size, mdtype);
 145   if (result != NULL) {
 146     return result;
 147   }
 148 
 149   // Start synchronous GC
 150   collect(GCCause::_metadata_GC_clear_soft_refs);
 151 
 152   // Retry allocation
 153   result = loader_data->metaspace_non_null()->allocate(size, mdtype);
 154   if (result != NULL) {
 155     return result;
 156   }
 157 
 158   // Expand and retry allocation
 159   result = loader_data->metaspace_non_null()->expand_and_allocate(size, mdtype);
 160   if (result != NULL) {
 161     return result;
 162   }
 163 
 164   // Out of memory
 165   return NULL;
 166 }
 167 
 168 void ZCollectedHeap::collect(GCCause::Cause cause) {
 169   _driver->collect(cause);
 170 }
 171 
 172 void ZCollectedHeap::collect_as_vm_thread(GCCause::Cause cause) {
 173   // These collection requests are ignored since ZGC can't run a synchronous
 174   // GC cycle from within the VM thread. This is considered benign, since the
 175   // only GC causes coming in here should be heap dumper and heap inspector.
 176   // However, neither the heap dumper nor the heap inspector really need a GC
 177   // to happen, but the result of their heap iterations might in that case be
 178   // less accurate since they might include objects that would otherwise have
 179   // been collected by a GC.
 180   assert(Thread::current()->is_VM_thread(), "Should be the VM thread");
 181   guarantee(cause == GCCause::_heap_dump ||
 182             cause == GCCause::_heap_inspection, "Invalid cause");
 183 }
 184 
 185 void ZCollectedHeap::do_full_collection(bool clear_all_soft_refs) {
 186   // Not supported
 187   ShouldNotReachHere();
 188 }
 189 
 190 bool ZCollectedHeap::supports_tlab_allocation() const {
 191   return true;
 192 }
 193 
 194 size_t ZCollectedHeap::tlab_capacity(Thread* ignored) const {
 195   return _heap.tlab_capacity();
 196 }
 197 
 198 size_t ZCollectedHeap::tlab_used(Thread* ignored) const {
 199   return _heap.tlab_used();
 200 }
 201 
 202 size_t ZCollectedHeap::max_tlab_size() const {
 203   return _heap.max_tlab_size();
 204 }
 205 
 206 size_t ZCollectedHeap::unsafe_max_tlab_alloc(Thread* ignored) const {
 207   return _heap.unsafe_max_tlab_alloc();
 208 }
 209 
 210 bool ZCollectedHeap::can_elide_tlab_store_barriers() const {
 211   return false;
 212 }
 213 
 214 bool ZCollectedHeap::can_elide_initializing_store_barrier(oop new_obj) {
 215   // Not supported
 216   ShouldNotReachHere();
 217   return true;
 218 }
 219 
 220 bool ZCollectedHeap::card_mark_must_follow_store() const {
 221   // Not supported
 222   ShouldNotReachHere();
 223   return false;
 224 }
 225 
 226 GrowableArray<GCMemoryManager*> ZCollectedHeap::memory_managers() {
 227   return GrowableArray<GCMemoryManager*>(1, 1, _heap.serviceability_memory_manager());
 228 }
 229 
 230 GrowableArray<MemoryPool*> ZCollectedHeap::memory_pools() {
 231   return GrowableArray<MemoryPool*>(1, 1, _heap.serviceability_memory_pool());
 232 }
 233 
 234 void ZCollectedHeap::object_iterate(ObjectClosure* cl) {
 235   _heap.object_iterate(cl, true /* visit_referents */);
 236 }
 237 
 238 void ZCollectedHeap::safe_object_iterate(ObjectClosure* cl) {
 239   _heap.object_iterate(cl, true /* visit_referents */);
 240 }
 241 
 242 HeapWord* ZCollectedHeap::block_start(const void* addr) const {
 243   return (HeapWord*)_heap.block_start((uintptr_t)addr);
 244 }
 245 
 246 bool ZCollectedHeap::block_is_obj(const HeapWord* addr) const {
 247   return _heap.block_is_obj((uintptr_t)addr);
 248 }
 249 
 250 void ZCollectedHeap::register_nmethod(nmethod* nm) {
 251   ZNMethod::register_nmethod(nm);
 252 }
 253 
 254 void ZCollectedHeap::unregister_nmethod(nmethod* nm) {
 255   ZNMethod::unregister_nmethod(nm);
 256 }
 257 
 258 void ZCollectedHeap::flush_nmethod(nmethod* nm) {
 259   ZNMethod::flush_nmethod(nm);
 260 }
 261 
 262 void ZCollectedHeap::verify_nmethod(nmethod* nm) {
 263   // Does nothing
 264 }
 265 
 266 WorkGang* ZCollectedHeap::get_safepoint_workers() {
 267   return _runtime_workers.workers();
 268 }
 269 
 270 jlong ZCollectedHeap::millis_since_last_gc() {
 271   return ZStatCycle::time_since_last() / MILLIUNITS;
 272 }
 273 
 274 void ZCollectedHeap::gc_threads_do(ThreadClosure* tc) const {
 275   tc->do_thread(_director);
 276   tc->do_thread(_driver);
 277   tc->do_thread(_uncommitter);
 278   tc->do_thread(_stat);
 279   _heap.worker_threads_do(tc);
 280   _runtime_workers.threads_do(tc);
 281 }
 282 
 283 VirtualSpaceSummary ZCollectedHeap::create_heap_space_summary() {
 284   const size_t capacity_in_words = capacity() / HeapWordSize;
 285   const size_t max_capacity_in_words = max_capacity() / HeapWordSize;
 286   return VirtualSpaceSummary(reserved_region().start(),
 287                              reserved_region().start() + capacity_in_words,
 288                              reserved_region().start() + max_capacity_in_words);
 289 }
 290 
 291 void ZCollectedHeap::safepoint_synchronize_begin() {
 292   SuspendibleThreadSet::synchronize();
 293 }
 294 
 295 void ZCollectedHeap::safepoint_synchronize_end() {
 296   SuspendibleThreadSet::desynchronize();
 297 }
 298 
 299 void ZCollectedHeap::prepare_for_verify() {
 300   // Does nothing
 301 }
 302 
 303 void ZCollectedHeap::print_on(outputStream* st) const {
 304   _heap.print_on(st);
 305 }
 306 
 307 void ZCollectedHeap::print_on_error(outputStream* st) const {
 308   CollectedHeap::print_on_error(st);
 309 
 310   st->print_cr("Address Space");
 311   st->print_cr( "     Start:             " PTR_FORMAT, ZAddressSpaceStart);
 312   st->print_cr( "     End:               " PTR_FORMAT, ZAddressSpaceEnd);
 313   st->print_cr( "     Size:              " SIZE_FORMAT_W(-15) " (" PTR_FORMAT ")", ZAddressSpaceSize, ZAddressSpaceSize);
 314   st->print_cr( "Heap");
 315   st->print_cr( "     GlobalPhase:       %u", ZGlobalPhase);
 316   st->print_cr( "     GlobalSeqNum:      %u", ZGlobalSeqNum);
 317   st->print_cr( "     Offset Max:        " SIZE_FORMAT_W(-15) " (" PTR_FORMAT ")", ZAddressOffsetMax, ZAddressOffsetMax);
 318   st->print_cr( "     Page Size Small:   " SIZE_FORMAT_W(-15) " (" PTR_FORMAT ")", ZPageSizeSmall, ZPageSizeSmall);
 319   st->print_cr( "     Page Size Medium:  " SIZE_FORMAT_W(-15) " (" PTR_FORMAT ")", ZPageSizeMedium, ZPageSizeMedium);
 320   st->print_cr( "Metadata Bits");
 321   st->print_cr( "     Good:              " PTR_FORMAT, ZAddressGoodMask);
 322   st->print_cr( "     Bad:               " PTR_FORMAT, ZAddressBadMask);
 323   st->print_cr( "     WeakBad:           " PTR_FORMAT, ZAddressWeakBadMask);
 324   st->print_cr( "     Marked:            " PTR_FORMAT, ZAddressMetadataMarked);
 325   st->print_cr( "     Remapped:          " PTR_FORMAT, ZAddressMetadataRemapped);
 326 }
 327 
 328 void ZCollectedHeap::print_extended_on(outputStream* st) const {
 329   _heap.print_extended_on(st);
 330 }
 331 
 332 void ZCollectedHeap::print_gc_threads_on(outputStream* st) const {
 333   _director->print_on(st);
 334   st->cr();
 335   _driver->print_on(st);
 336   st->cr();
 337   _uncommitter->print_on(st);
 338   st->cr();
 339   _stat->print_on(st);
 340   st->cr();
 341   _heap.print_worker_threads_on(st);
 342   _runtime_workers.print_threads_on(st);
 343 }
 344 
 345 void ZCollectedHeap::print_tracing_info() const {
 346   // Does nothing
 347 }
 348 
 349 void ZCollectedHeap::verify(VerifyOption option /* ignored */) {
 350   _heap.verify();
 351 }
 352 
 353 bool ZCollectedHeap::is_oop(oop object) const {
 354   return CollectedHeap::is_oop(object) && _heap.is_oop(object);
 355 }