1 /*
   2  * Copyright (c) 2011, 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 
  25 #include "precompiled.hpp"
  26 #include "aot/aotLoader.hpp"
  27 #include "classfile/classLoaderDataGraph.hpp"
  28 #include "gc/shared/collectedHeap.hpp"
  29 #include "logging/log.hpp"
  30 #include "logging/logStream.hpp"
  31 #include "memory/filemap.hpp"
  32 #include "memory/metaspace.hpp"
  33 #include "memory/metaspace/chunkManager.hpp"
  34 #include "memory/metaspace/metachunk.hpp"
  35 #include "memory/metaspace/metaspaceCommon.hpp"
  36 #include "memory/metaspace/printCLDMetaspaceInfoClosure.hpp"
  37 #include "memory/metaspace/spaceManager.hpp"
  38 #include "memory/metaspace/virtualSpaceList.hpp"
  39 #include "memory/metaspaceShared.hpp"
  40 #include "memory/metaspaceTracer.hpp"
  41 #include "memory/universe.hpp"
  42 #include "oops/compressedOops.hpp"
  43 #include "runtime/init.hpp"
  44 #include "runtime/orderAccess.hpp"
  45 #include "services/memTracker.hpp"
  46 #include "utilities/copy.hpp"
  47 #include "utilities/debug.hpp"
  48 #include "utilities/formatBuffer.hpp"
  49 #include "utilities/globalDefinitions.hpp"
  50 #include "utilities/vmError.hpp"
  51 
  52 
  53 using namespace metaspace;
  54 
  55 MetaWord* last_allocated = 0;
  56 
  57 size_t Metaspace::_compressed_class_space_size;
  58 const MetaspaceTracer* Metaspace::_tracer = NULL;
  59 
  60 DEBUG_ONLY(bool Metaspace::_frozen = false;)
  61 
  62 static const char* space_type_name(Metaspace::MetaspaceType t) {
  63   const char* s = NULL;
  64   switch (t) {
  65     case Metaspace::StandardMetaspaceType: s = "Standard"; break;
  66     case Metaspace::BootMetaspaceType: s = "Boot"; break;
  67     case Metaspace::UnsafeAnonymousMetaspaceType: s = "UnsafeAnonymous"; break;
  68     case Metaspace::ReflectionMetaspaceType: s = "Reflection"; break;
  69     default: ShouldNotReachHere();
  70   }
  71   return s;
  72 }
  73 
  74 volatile size_t MetaspaceGC::_capacity_until_GC = 0;
  75 uint MetaspaceGC::_shrink_factor = 0;
  76 
  77 // BlockFreelist methods
  78 
  79 // VirtualSpaceNode methods
  80 
  81 // MetaspaceGC methods
  82 
  83 // VM_CollectForMetadataAllocation is the vm operation used to GC.
  84 // Within the VM operation after the GC the attempt to allocate the metadata
  85 // should succeed.  If the GC did not free enough space for the metaspace
  86 // allocation, the HWM is increased so that another virtualspace will be
  87 // allocated for the metadata.  With perm gen the increase in the perm
  88 // gen had bounds, MinMetaspaceExpansion and MaxMetaspaceExpansion.  The
  89 // metaspace policy uses those as the small and large steps for the HWM.
  90 //
  91 // After the GC the compute_new_size() for MetaspaceGC is called to
  92 // resize the capacity of the metaspaces.  The current implementation
  93 // is based on the flags MinMetaspaceFreeRatio and MaxMetaspaceFreeRatio used
  94 // to resize the Java heap by some GC's.  New flags can be implemented
  95 // if really needed.  MinMetaspaceFreeRatio is used to calculate how much
  96 // free space is desirable in the metaspace capacity to decide how much
  97 // to increase the HWM.  MaxMetaspaceFreeRatio is used to decide how much
  98 // free space is desirable in the metaspace capacity before decreasing
  99 // the HWM.
 100 
 101 // Calculate the amount to increase the high water mark (HWM).
 102 // Increase by a minimum amount (MinMetaspaceExpansion) so that
 103 // another expansion is not requested too soon.  If that is not
 104 // enough to satisfy the allocation, increase by MaxMetaspaceExpansion.
 105 // If that is still not enough, expand by the size of the allocation
 106 // plus some.
 107 size_t MetaspaceGC::delta_capacity_until_GC(size_t bytes) {
 108   size_t min_delta = MinMetaspaceExpansion;
 109   size_t max_delta = MaxMetaspaceExpansion;
 110   size_t delta = align_up(bytes, Metaspace::commit_alignment());
 111 
 112   if (delta <= min_delta) {
 113     delta = min_delta;
 114   } else if (delta <= max_delta) {
 115     // Don't want to hit the high water mark on the next
 116     // allocation so make the delta greater than just enough
 117     // for this allocation.
 118     delta = max_delta;
 119   } else {
 120     // This allocation is large but the next ones are probably not
 121     // so increase by the minimum.
 122     delta = delta + min_delta;
 123   }
 124 
 125   assert_is_aligned(delta, Metaspace::commit_alignment());
 126 
 127   return delta;
 128 }
 129 
 130 size_t MetaspaceGC::capacity_until_GC() {
 131   size_t value = OrderAccess::load_acquire(&_capacity_until_GC);
 132   assert(value >= MetaspaceSize, "Not initialized properly?");
 133   return value;
 134 }
 135 
 136 // Try to increase the _capacity_until_GC limit counter by v bytes.
 137 // Returns true if it succeeded. It may fail if either another thread
 138 // concurrently increased the limit or the new limit would be larger
 139 // than MaxMetaspaceSize.
 140 // On success, optionally returns new and old metaspace capacity in
 141 // new_cap_until_GC and old_cap_until_GC respectively.
 142 // On error, optionally sets can_retry to indicate whether if there is
 143 // actually enough space remaining to satisfy the request.
 144 bool MetaspaceGC::inc_capacity_until_GC(size_t v, size_t* new_cap_until_GC, size_t* old_cap_until_GC, bool* can_retry) {
 145   assert_is_aligned(v, Metaspace::commit_alignment());
 146 
 147   size_t old_capacity_until_GC = _capacity_until_GC;
 148   size_t new_value = old_capacity_until_GC + v;
 149 
 150   if (new_value < old_capacity_until_GC) {
 151     // The addition wrapped around, set new_value to aligned max value.
 152     new_value = align_down(max_uintx, Metaspace::commit_alignment());
 153   }
 154 
 155   if (new_value > MaxMetaspaceSize) {
 156     if (can_retry != NULL) {
 157       *can_retry = false;
 158     }
 159     return false;
 160   }
 161 
 162   if (can_retry != NULL) {
 163     *can_retry = true;
 164   }
 165   size_t prev_value = Atomic::cmpxchg(new_value, &_capacity_until_GC, old_capacity_until_GC);
 166 
 167   if (old_capacity_until_GC != prev_value) {
 168     return false;
 169   }
 170 
 171   if (new_cap_until_GC != NULL) {
 172     *new_cap_until_GC = new_value;
 173   }
 174   if (old_cap_until_GC != NULL) {
 175     *old_cap_until_GC = old_capacity_until_GC;
 176   }
 177   return true;
 178 }
 179 
 180 size_t MetaspaceGC::dec_capacity_until_GC(size_t v) {
 181   assert_is_aligned(v, Metaspace::commit_alignment());
 182 
 183   return Atomic::sub(v, &_capacity_until_GC);
 184 }
 185 
 186 void MetaspaceGC::initialize() {
 187   // Set the high-water mark to MaxMetapaceSize during VM initializaton since
 188   // we can't do a GC during initialization.
 189   _capacity_until_GC = MaxMetaspaceSize;
 190 }
 191 
 192 void MetaspaceGC::post_initialize() {
 193   // Reset the high-water mark once the VM initialization is done.
 194   _capacity_until_GC = MAX2(MetaspaceUtils::committed_bytes(), MetaspaceSize);
 195 }
 196 
 197 bool MetaspaceGC::can_expand(size_t word_size, bool is_class) {
 198   // Check if the compressed class space is full.
 199   if (is_class && Metaspace::using_class_space()) {
 200     size_t class_committed = MetaspaceUtils::committed_bytes(Metaspace::ClassType);
 201     if (class_committed + word_size * BytesPerWord > CompressedClassSpaceSize) {
 202       log_trace(gc, metaspace, freelist)("Cannot expand %s metaspace by " SIZE_FORMAT " words (CompressedClassSpaceSize = " SIZE_FORMAT " words)",
 203                 (is_class ? "class" : "non-class"), word_size, CompressedClassSpaceSize / sizeof(MetaWord));
 204       return false;
 205     }
 206   }
 207 
 208   // Check if the user has imposed a limit on the metaspace memory.
 209   size_t committed_bytes = MetaspaceUtils::committed_bytes();
 210   if (committed_bytes + word_size * BytesPerWord > MaxMetaspaceSize) {
 211     log_trace(gc, metaspace, freelist)("Cannot expand %s metaspace by " SIZE_FORMAT " words (MaxMetaspaceSize = " SIZE_FORMAT " words)",
 212               (is_class ? "class" : "non-class"), word_size, MaxMetaspaceSize / sizeof(MetaWord));
 213     return false;
 214   }
 215 
 216   return true;
 217 }
 218 
 219 size_t MetaspaceGC::allowed_expansion() {
 220   size_t committed_bytes = MetaspaceUtils::committed_bytes();
 221   size_t capacity_until_gc = capacity_until_GC();
 222 
 223   assert(capacity_until_gc >= committed_bytes,
 224          "capacity_until_gc: " SIZE_FORMAT " < committed_bytes: " SIZE_FORMAT,
 225          capacity_until_gc, committed_bytes);
 226 
 227   size_t left_until_max  = MaxMetaspaceSize - committed_bytes;
 228   size_t left_until_GC = capacity_until_gc - committed_bytes;
 229   size_t left_to_commit = MIN2(left_until_GC, left_until_max);
 230   log_trace(gc, metaspace, freelist)("allowed expansion words: " SIZE_FORMAT
 231             " (left_until_max: " SIZE_FORMAT ", left_until_GC: " SIZE_FORMAT ".",
 232             left_to_commit / BytesPerWord, left_until_max / BytesPerWord, left_until_GC / BytesPerWord);
 233 
 234   return left_to_commit / BytesPerWord;
 235 }
 236 
 237 void MetaspaceGC::compute_new_size() {
 238   assert(_shrink_factor <= 100, "invalid shrink factor");
 239   uint current_shrink_factor = _shrink_factor;
 240   _shrink_factor = 0;
 241 
 242   // Using committed_bytes() for used_after_gc is an overestimation, since the
 243   // chunk free lists are included in committed_bytes() and the memory in an
 244   // un-fragmented chunk free list is available for future allocations.
 245   // However, if the chunk free lists becomes fragmented, then the memory may
 246   // not be available for future allocations and the memory is therefore "in use".
 247   // Including the chunk free lists in the definition of "in use" is therefore
 248   // necessary. Not including the chunk free lists can cause capacity_until_GC to
 249   // shrink below committed_bytes() and this has caused serious bugs in the past.
 250   const size_t used_after_gc = MetaspaceUtils::committed_bytes();
 251   const size_t capacity_until_GC = MetaspaceGC::capacity_until_GC();
 252 
 253   const double minimum_free_percentage = MinMetaspaceFreeRatio / 100.0;
 254   const double maximum_used_percentage = 1.0 - minimum_free_percentage;
 255 
 256   const double min_tmp = used_after_gc / maximum_used_percentage;
 257   size_t minimum_desired_capacity =
 258     (size_t)MIN2(min_tmp, double(MaxMetaspaceSize));
 259   // Don't shrink less than the initial generation size
 260   minimum_desired_capacity = MAX2(minimum_desired_capacity,
 261                                   MetaspaceSize);
 262 
 263   log_trace(gc, metaspace)("MetaspaceGC::compute_new_size: ");
 264   log_trace(gc, metaspace)("    minimum_free_percentage: %6.2f  maximum_used_percentage: %6.2f",
 265                            minimum_free_percentage, maximum_used_percentage);
 266   log_trace(gc, metaspace)("     used_after_gc       : %6.1fKB", used_after_gc / (double) K);
 267 
 268 
 269   size_t shrink_bytes = 0;
 270   if (capacity_until_GC < minimum_desired_capacity) {
 271     // If we have less capacity below the metaspace HWM, then
 272     // increment the HWM.
 273     size_t expand_bytes = minimum_desired_capacity - capacity_until_GC;
 274     expand_bytes = align_up(expand_bytes, Metaspace::commit_alignment());
 275     // Don't expand unless it's significant
 276     if (expand_bytes >= MinMetaspaceExpansion) {
 277       size_t new_capacity_until_GC = 0;
 278       bool succeeded = MetaspaceGC::inc_capacity_until_GC(expand_bytes, &new_capacity_until_GC);
 279       assert(succeeded, "Should always succesfully increment HWM when at safepoint");
 280 
 281       Metaspace::tracer()->report_gc_threshold(capacity_until_GC,
 282                                                new_capacity_until_GC,
 283                                                MetaspaceGCThresholdUpdater::ComputeNewSize);
 284       log_trace(gc, metaspace)("    expanding:  minimum_desired_capacity: %6.1fKB  expand_bytes: %6.1fKB  MinMetaspaceExpansion: %6.1fKB  new metaspace HWM:  %6.1fKB",
 285                                minimum_desired_capacity / (double) K,
 286                                expand_bytes / (double) K,
 287                                MinMetaspaceExpansion / (double) K,
 288                                new_capacity_until_GC / (double) K);
 289     }
 290     return;
 291   }
 292 
 293   // No expansion, now see if we want to shrink
 294   // We would never want to shrink more than this
 295   assert(capacity_until_GC >= minimum_desired_capacity,
 296          SIZE_FORMAT " >= " SIZE_FORMAT,
 297          capacity_until_GC, minimum_desired_capacity);
 298   size_t max_shrink_bytes = capacity_until_GC - minimum_desired_capacity;
 299 
 300   // Should shrinking be considered?
 301   if (MaxMetaspaceFreeRatio < 100) {
 302     const double maximum_free_percentage = MaxMetaspaceFreeRatio / 100.0;
 303     const double minimum_used_percentage = 1.0 - maximum_free_percentage;
 304     const double max_tmp = used_after_gc / minimum_used_percentage;
 305     size_t maximum_desired_capacity = (size_t)MIN2(max_tmp, double(MaxMetaspaceSize));
 306     maximum_desired_capacity = MAX2(maximum_desired_capacity,
 307                                     MetaspaceSize);
 308     log_trace(gc, metaspace)("    maximum_free_percentage: %6.2f  minimum_used_percentage: %6.2f",
 309                              maximum_free_percentage, minimum_used_percentage);
 310     log_trace(gc, metaspace)("    minimum_desired_capacity: %6.1fKB  maximum_desired_capacity: %6.1fKB",
 311                              minimum_desired_capacity / (double) K, maximum_desired_capacity / (double) K);
 312 
 313     assert(minimum_desired_capacity <= maximum_desired_capacity,
 314            "sanity check");
 315 
 316     if (capacity_until_GC > maximum_desired_capacity) {
 317       // Capacity too large, compute shrinking size
 318       shrink_bytes = capacity_until_GC - maximum_desired_capacity;
 319       // We don't want shrink all the way back to initSize if people call
 320       // System.gc(), because some programs do that between "phases" and then
 321       // we'd just have to grow the heap up again for the next phase.  So we
 322       // damp the shrinking: 0% on the first call, 10% on the second call, 40%
 323       // on the third call, and 100% by the fourth call.  But if we recompute
 324       // size without shrinking, it goes back to 0%.
 325       shrink_bytes = shrink_bytes / 100 * current_shrink_factor;
 326 
 327       shrink_bytes = align_down(shrink_bytes, Metaspace::commit_alignment());
 328 
 329       assert(shrink_bytes <= max_shrink_bytes,
 330              "invalid shrink size " SIZE_FORMAT " not <= " SIZE_FORMAT,
 331              shrink_bytes, max_shrink_bytes);
 332       if (current_shrink_factor == 0) {
 333         _shrink_factor = 10;
 334       } else {
 335         _shrink_factor = MIN2(current_shrink_factor * 4, (uint) 100);
 336       }
 337       log_trace(gc, metaspace)("    shrinking:  initThreshold: %.1fK  maximum_desired_capacity: %.1fK",
 338                                MetaspaceSize / (double) K, maximum_desired_capacity / (double) K);
 339       log_trace(gc, metaspace)("    shrink_bytes: %.1fK  current_shrink_factor: %d  new shrink factor: %d  MinMetaspaceExpansion: %.1fK",
 340                                shrink_bytes / (double) K, current_shrink_factor, _shrink_factor, MinMetaspaceExpansion / (double) K);
 341     }
 342   }
 343 
 344   // Don't shrink unless it's significant
 345   if (shrink_bytes >= MinMetaspaceExpansion &&
 346       ((capacity_until_GC - shrink_bytes) >= MetaspaceSize)) {
 347     size_t new_capacity_until_GC = MetaspaceGC::dec_capacity_until_GC(shrink_bytes);
 348     Metaspace::tracer()->report_gc_threshold(capacity_until_GC,
 349                                              new_capacity_until_GC,
 350                                              MetaspaceGCThresholdUpdater::ComputeNewSize);
 351   }
 352 }
 353 
 354 // MetaspaceUtils
 355 size_t MetaspaceUtils::_capacity_words [Metaspace:: MetadataTypeCount] = {0, 0};
 356 size_t MetaspaceUtils::_overhead_words [Metaspace:: MetadataTypeCount] = {0, 0};
 357 volatile size_t MetaspaceUtils::_used_words [Metaspace:: MetadataTypeCount] = {0, 0};
 358 
 359 // Collect used metaspace statistics. This involves walking the CLDG. The resulting
 360 // output will be the accumulated values for all live metaspaces.
 361 // Note: method does not do any locking.
 362 void MetaspaceUtils::collect_statistics(ClassLoaderMetaspaceStatistics* out) {
 363   out->reset();
 364   ClassLoaderDataGraphMetaspaceIterator iter;
 365    while (iter.repeat()) {
 366      ClassLoaderMetaspace* msp = iter.get_next();
 367      if (msp != NULL) {
 368        msp->add_to_statistics(out);
 369      }
 370    }
 371 }
 372 
 373 size_t MetaspaceUtils::free_in_vs_bytes(Metaspace::MetadataType mdtype) {
 374   VirtualSpaceList* list = Metaspace::get_space_list(mdtype);
 375   return list == NULL ? 0 : list->free_bytes();
 376 }
 377 
 378 size_t MetaspaceUtils::free_in_vs_bytes() {
 379   return free_in_vs_bytes(Metaspace::ClassType) + free_in_vs_bytes(Metaspace::NonClassType);
 380 }
 381 
 382 static void inc_stat_nonatomically(size_t* pstat, size_t words) {
 383   assert_lock_strong(MetaspaceExpand_lock);
 384   (*pstat) += words;
 385 }
 386 
 387 static void dec_stat_nonatomically(size_t* pstat, size_t words) {
 388   assert_lock_strong(MetaspaceExpand_lock);
 389   const size_t size_now = *pstat;
 390   assert(size_now >= words, "About to decrement counter below zero "
 391          "(current value: " SIZE_FORMAT ", decrement value: " SIZE_FORMAT ".",
 392          size_now, words);
 393   *pstat = size_now - words;
 394 }
 395 
 396 static void inc_stat_atomically(volatile size_t* pstat, size_t words) {
 397   Atomic::add(words, pstat);
 398 }
 399 
 400 static void dec_stat_atomically(volatile size_t* pstat, size_t words) {
 401   const size_t size_now = *pstat;
 402   assert(size_now >= words, "About to decrement counter below zero "
 403          "(current value: " SIZE_FORMAT ", decrement value: " SIZE_FORMAT ".",
 404          size_now, words);
 405   Atomic::sub(words, pstat);
 406 }
 407 
 408 void MetaspaceUtils::dec_capacity(Metaspace::MetadataType mdtype, size_t words) {
 409   dec_stat_nonatomically(&_capacity_words[mdtype], words);
 410 }
 411 void MetaspaceUtils::inc_capacity(Metaspace::MetadataType mdtype, size_t words) {
 412   inc_stat_nonatomically(&_capacity_words[mdtype], words);
 413 }
 414 void MetaspaceUtils::dec_used(Metaspace::MetadataType mdtype, size_t words) {
 415   dec_stat_atomically(&_used_words[mdtype], words);
 416 }
 417 void MetaspaceUtils::inc_used(Metaspace::MetadataType mdtype, size_t words) {
 418   inc_stat_atomically(&_used_words[mdtype], words);
 419 }
 420 void MetaspaceUtils::dec_overhead(Metaspace::MetadataType mdtype, size_t words) {
 421   dec_stat_nonatomically(&_overhead_words[mdtype], words);
 422 }
 423 void MetaspaceUtils::inc_overhead(Metaspace::MetadataType mdtype, size_t words) {
 424   inc_stat_nonatomically(&_overhead_words[mdtype], words);
 425 }
 426 
 427 size_t MetaspaceUtils::reserved_bytes(Metaspace::MetadataType mdtype) {
 428   VirtualSpaceList* list = Metaspace::get_space_list(mdtype);
 429   return list == NULL ? 0 : list->reserved_bytes();
 430 }
 431 
 432 size_t MetaspaceUtils::committed_bytes(Metaspace::MetadataType mdtype) {
 433   VirtualSpaceList* list = Metaspace::get_space_list(mdtype);
 434   return list == NULL ? 0 : list->committed_bytes();
 435 }
 436 
 437 size_t MetaspaceUtils::min_chunk_size_words() { return Metaspace::first_chunk_word_size(); }
 438 
 439 size_t MetaspaceUtils::free_chunks_total_words(Metaspace::MetadataType mdtype) {
 440   ChunkManager* chunk_manager = Metaspace::get_chunk_manager(mdtype);
 441   if (chunk_manager == NULL) {
 442     return 0;
 443   }
 444   return chunk_manager->free_chunks_total_words();
 445 }
 446 
 447 size_t MetaspaceUtils::free_chunks_total_bytes(Metaspace::MetadataType mdtype) {
 448   return free_chunks_total_words(mdtype) * BytesPerWord;
 449 }
 450 
 451 size_t MetaspaceUtils::free_chunks_total_words() {
 452   return free_chunks_total_words(Metaspace::ClassType) +
 453          free_chunks_total_words(Metaspace::NonClassType);
 454 }
 455 
 456 size_t MetaspaceUtils::free_chunks_total_bytes() {
 457   return free_chunks_total_words() * BytesPerWord;
 458 }
 459 
 460 bool MetaspaceUtils::has_chunk_free_list(Metaspace::MetadataType mdtype) {
 461   return Metaspace::get_chunk_manager(mdtype) != NULL;
 462 }
 463 
 464 MetaspaceChunkFreeListSummary MetaspaceUtils::chunk_free_list_summary(Metaspace::MetadataType mdtype) {
 465   if (!has_chunk_free_list(mdtype)) {
 466     return MetaspaceChunkFreeListSummary();
 467   }
 468 
 469   const ChunkManager* cm = Metaspace::get_chunk_manager(mdtype);
 470   return cm->chunk_free_list_summary();
 471 }
 472 
 473 void MetaspaceUtils::print_metaspace_change(const metaspace::MetaspaceSizesSnapshot& pre_meta_values) {
 474   const metaspace::MetaspaceSizesSnapshot meta_values;
 475 
 476   if (Metaspace::using_class_space()) {
 477     log_info(gc, metaspace)(HEAP_CHANGE_FORMAT" "
 478                             HEAP_CHANGE_FORMAT" "
 479                             HEAP_CHANGE_FORMAT,
 480                             HEAP_CHANGE_FORMAT_ARGS("Metaspace",
 481                                                     pre_meta_values.used(),
 482                                                     pre_meta_values.committed(),
 483                                                     meta_values.used(),
 484                                                     meta_values.committed()),
 485                             HEAP_CHANGE_FORMAT_ARGS("NonClass",
 486                                                     pre_meta_values.non_class_used(),
 487                                                     pre_meta_values.non_class_committed(),
 488                                                     meta_values.non_class_used(),
 489                                                     meta_values.non_class_committed()),
 490                             HEAP_CHANGE_FORMAT_ARGS("Class",
 491                                                     pre_meta_values.class_used(),
 492                                                     pre_meta_values.class_committed(),
 493                                                     meta_values.class_used(),
 494                                                     meta_values.class_committed()));
 495   } else {
 496     log_info(gc, metaspace)(HEAP_CHANGE_FORMAT,
 497                             HEAP_CHANGE_FORMAT_ARGS("Metaspace",
 498                                                     pre_meta_values.used(),
 499                                                     pre_meta_values.committed(),
 500                                                     meta_values.used(),
 501                                                     meta_values.committed()));
 502   }
 503 }
 504 
 505 void MetaspaceUtils::print_on(outputStream* out) {
 506   Metaspace::MetadataType nct = Metaspace::NonClassType;
 507 
 508   out->print_cr(" Metaspace       "
 509                 "used "      SIZE_FORMAT "K, "
 510                 "capacity "  SIZE_FORMAT "K, "
 511                 "committed " SIZE_FORMAT "K, "
 512                 "reserved "  SIZE_FORMAT "K",
 513                 used_bytes()/K,
 514                 capacity_bytes()/K,
 515                 committed_bytes()/K,
 516                 reserved_bytes()/K);
 517 
 518   if (Metaspace::using_class_space()) {
 519     Metaspace::MetadataType ct = Metaspace::ClassType;
 520     out->print_cr("  class space    "
 521                   "used "      SIZE_FORMAT "K, "
 522                   "capacity "  SIZE_FORMAT "K, "
 523                   "committed " SIZE_FORMAT "K, "
 524                   "reserved "  SIZE_FORMAT "K",
 525                   used_bytes(ct)/K,
 526                   capacity_bytes(ct)/K,
 527                   committed_bytes(ct)/K,
 528                   reserved_bytes(ct)/K);
 529   }
 530 }
 531 
 532 
 533 void MetaspaceUtils::print_vs(outputStream* out, size_t scale) {
 534   const size_t reserved_nonclass_words = reserved_bytes(Metaspace::NonClassType) / sizeof(MetaWord);
 535   const size_t committed_nonclass_words = committed_bytes(Metaspace::NonClassType) / sizeof(MetaWord);
 536   {
 537     if (Metaspace::using_class_space()) {
 538       out->print("  Non-class space:  ");
 539     }
 540     print_scaled_words(out, reserved_nonclass_words, scale, 7);
 541     out->print(" reserved, ");
 542     print_scaled_words_and_percentage(out, committed_nonclass_words, reserved_nonclass_words, scale, 7);
 543     out->print_cr(" committed ");
 544 
 545     if (Metaspace::using_class_space()) {
 546       const size_t reserved_class_words = reserved_bytes(Metaspace::ClassType) / sizeof(MetaWord);
 547       const size_t committed_class_words = committed_bytes(Metaspace::ClassType) / sizeof(MetaWord);
 548       out->print("      Class space:  ");
 549       print_scaled_words(out, reserved_class_words, scale, 7);
 550       out->print(" reserved, ");
 551       print_scaled_words_and_percentage(out, committed_class_words, reserved_class_words, scale, 7);
 552       out->print_cr(" committed ");
 553 
 554       const size_t reserved_words = reserved_nonclass_words + reserved_class_words;
 555       const size_t committed_words = committed_nonclass_words + committed_class_words;
 556       out->print("             Both:  ");
 557       print_scaled_words(out, reserved_words, scale, 7);
 558       out->print(" reserved, ");
 559       print_scaled_words_and_percentage(out, committed_words, reserved_words, scale, 7);
 560       out->print_cr(" committed ");
 561     }
 562   }
 563 }
 564 
 565 static void print_basic_switches(outputStream* out, size_t scale) {
 566   out->print("MaxMetaspaceSize: ");
 567   if (MaxMetaspaceSize >= (max_uintx) - (2 * os::vm_page_size())) {
 568     // aka "very big". Default is max_uintx, but due to rounding in arg parsing the real
 569     // value is smaller.
 570     out->print("unlimited");
 571   } else {
 572     print_human_readable_size(out, MaxMetaspaceSize, scale);
 573   }
 574   out->cr();
 575   if (Metaspace::using_class_space()) {
 576     out->print("CompressedClassSpaceSize: ");
 577     print_human_readable_size(out, CompressedClassSpaceSize, scale);
 578   }
 579   out->cr();
 580 }
 581 
 582 // This will print out a basic metaspace usage report but
 583 // unlike print_report() is guaranteed not to lock or to walk the CLDG.
 584 void MetaspaceUtils::print_basic_report(outputStream* out, size_t scale) {
 585 
 586   if (!Metaspace::initialized()) {
 587     out->print_cr("Metaspace not yet initialized.");
 588     return;
 589   }
 590 
 591   out->cr();
 592   out->print_cr("Usage:");
 593 
 594   if (Metaspace::using_class_space()) {
 595     out->print("  Non-class:  ");
 596   }
 597 
 598   // In its most basic form, we do not require walking the CLDG. Instead, just print the running totals from
 599   // MetaspaceUtils.
 600   const size_t cap_nc = MetaspaceUtils::capacity_words(Metaspace::NonClassType);
 601   const size_t overhead_nc = MetaspaceUtils::overhead_words(Metaspace::NonClassType);
 602   const size_t used_nc = MetaspaceUtils::used_words(Metaspace::NonClassType);
 603   const size_t free_and_waste_nc = cap_nc - overhead_nc - used_nc;
 604 
 605   print_scaled_words(out, cap_nc, scale, 5);
 606   out->print(" capacity, ");
 607   print_scaled_words_and_percentage(out, used_nc, cap_nc, scale, 5);
 608   out->print(" used, ");
 609   print_scaled_words_and_percentage(out, free_and_waste_nc, cap_nc, scale, 5);
 610   out->print(" free+waste, ");
 611   print_scaled_words_and_percentage(out, overhead_nc, cap_nc, scale, 5);
 612   out->print(" overhead. ");
 613   out->cr();
 614 
 615   if (Metaspace::using_class_space()) {
 616     const size_t cap_c = MetaspaceUtils::capacity_words(Metaspace::ClassType);
 617     const size_t overhead_c = MetaspaceUtils::overhead_words(Metaspace::ClassType);
 618     const size_t used_c = MetaspaceUtils::used_words(Metaspace::ClassType);
 619     const size_t free_and_waste_c = cap_c - overhead_c - used_c;
 620     out->print("      Class:  ");
 621     print_scaled_words(out, cap_c, scale, 5);
 622     out->print(" capacity, ");
 623     print_scaled_words_and_percentage(out, used_c, cap_c, scale, 5);
 624     out->print(" used, ");
 625     print_scaled_words_and_percentage(out, free_and_waste_c, cap_c, scale, 5);
 626     out->print(" free+waste, ");
 627     print_scaled_words_and_percentage(out, overhead_c, cap_c, scale, 5);
 628     out->print(" overhead. ");
 629     out->cr();
 630 
 631     out->print("       Both:  ");
 632     const size_t cap = cap_nc + cap_c;
 633 
 634     print_scaled_words(out, cap, scale, 5);
 635     out->print(" capacity, ");
 636     print_scaled_words_and_percentage(out, used_nc + used_c, cap, scale, 5);
 637     out->print(" used, ");
 638     print_scaled_words_and_percentage(out, free_and_waste_nc + free_and_waste_c, cap, scale, 5);
 639     out->print(" free+waste, ");
 640     print_scaled_words_and_percentage(out, overhead_nc + overhead_c, cap, scale, 5);
 641     out->print(" overhead. ");
 642     out->cr();
 643   }
 644 
 645   out->cr();
 646   out->print_cr("Virtual space:");
 647 
 648   print_vs(out, scale);
 649 
 650   out->cr();
 651   out->print_cr("Chunk freelists:");
 652 
 653   if (Metaspace::using_class_space()) {
 654     out->print("   Non-Class:  ");
 655   }
 656   print_human_readable_size(out, Metaspace::chunk_manager_metadata()->free_chunks_total_bytes(), scale);
 657   out->cr();
 658   if (Metaspace::using_class_space()) {
 659     out->print("       Class:  ");
 660     print_human_readable_size(out, Metaspace::chunk_manager_class()->free_chunks_total_bytes(), scale);
 661     out->cr();
 662     out->print("        Both:  ");
 663     print_human_readable_size(out, Metaspace::chunk_manager_class()->free_chunks_total_bytes() +
 664                               Metaspace::chunk_manager_metadata()->free_chunks_total_bytes(), scale);
 665     out->cr();
 666   }
 667 
 668   out->cr();
 669 
 670   // Print basic settings
 671   print_basic_switches(out, scale);
 672 
 673   out->cr();
 674 
 675 }
 676 
 677 void MetaspaceUtils::print_report(outputStream* out, size_t scale, int flags) {
 678 
 679   if (!Metaspace::initialized()) {
 680     out->print_cr("Metaspace not yet initialized.");
 681     return;
 682   }
 683 
 684   const bool print_loaders = (flags & rf_show_loaders) > 0;
 685   const bool print_classes = (flags & rf_show_classes) > 0;
 686   const bool print_by_chunktype = (flags & rf_break_down_by_chunktype) > 0;
 687   const bool print_by_spacetype = (flags & rf_break_down_by_spacetype) > 0;
 688 
 689   // Some report options require walking the class loader data graph.
 690   PrintCLDMetaspaceInfoClosure cl(out, scale, print_loaders, print_classes, print_by_chunktype);
 691   if (print_loaders) {
 692     out->cr();
 693     out->print_cr("Usage per loader:");
 694     out->cr();
 695   }
 696 
 697   ClassLoaderDataGraph::loaded_cld_do(&cl); // collect data and optionally print
 698 
 699   // Print totals, broken up by space type.
 700   if (print_by_spacetype) {
 701     out->cr();
 702     out->print_cr("Usage per space type:");
 703     out->cr();
 704     for (int space_type = (int)Metaspace::ZeroMetaspaceType;
 705          space_type < (int)Metaspace::MetaspaceTypeCount; space_type ++)
 706     {
 707       uintx num_loaders = cl._num_loaders_by_spacetype[space_type];
 708       uintx num_classes = cl._num_classes_by_spacetype[space_type];
 709       out->print("%s - " UINTX_FORMAT " %s",
 710         space_type_name((Metaspace::MetaspaceType)space_type),
 711         num_loaders, loaders_plural(num_loaders));
 712       if (num_classes > 0) {
 713         out->print(", ");
 714         print_number_of_classes(out, num_classes, cl._num_classes_shared_by_spacetype[space_type]);
 715         out->print(":");
 716         cl._stats_by_spacetype[space_type].print_on(out, scale, print_by_chunktype);
 717       } else {
 718         out->print(".");
 719         out->cr();
 720       }
 721       out->cr();
 722     }
 723   }
 724 
 725   // Print totals for in-use data:
 726   out->cr();
 727   {
 728     uintx num_loaders = cl._num_loaders;
 729     out->print("Total Usage - " UINTX_FORMAT " %s, ",
 730       num_loaders, loaders_plural(num_loaders));
 731     print_number_of_classes(out, cl._num_classes, cl._num_classes_shared);
 732     out->print(":");
 733     cl._stats_total.print_on(out, scale, print_by_chunktype);
 734     out->cr();
 735   }
 736 
 737   // -- Print Virtual space.
 738   out->cr();
 739   out->print_cr("Virtual space:");
 740 
 741   print_vs(out, scale);
 742 
 743   // -- Print VirtualSpaceList details.
 744   if ((flags & rf_show_vslist) > 0) {
 745     out->cr();
 746     out->print_cr("Virtual space list%s:", Metaspace::using_class_space() ? "s" : "");
 747 
 748     if (Metaspace::using_class_space()) {
 749       out->print_cr("   Non-Class:");
 750     }
 751     Metaspace::space_list()->print_on(out, scale);
 752     if (Metaspace::using_class_space()) {
 753       out->print_cr("       Class:");
 754       Metaspace::class_space_list()->print_on(out, scale);
 755     }
 756   }
 757   out->cr();
 758 
 759   // -- Print VirtualSpaceList map.
 760   if ((flags & rf_show_vsmap) > 0) {
 761     out->cr();
 762     out->print_cr("Virtual space map:");
 763 
 764     if (Metaspace::using_class_space()) {
 765       out->print_cr("   Non-Class:");
 766     }
 767     Metaspace::space_list()->print_map(out);
 768     if (Metaspace::using_class_space()) {
 769       out->print_cr("       Class:");
 770       Metaspace::class_space_list()->print_map(out);
 771     }
 772   }
 773   out->cr();
 774 
 775   // -- Print Freelists (ChunkManager) details
 776   out->cr();
 777   out->print_cr("Chunk freelist%s:", Metaspace::using_class_space() ? "s" : "");
 778 
 779   ChunkManagerStatistics non_class_cm_stat;
 780   Metaspace::chunk_manager_metadata()->collect_statistics(&non_class_cm_stat);
 781 
 782   if (Metaspace::using_class_space()) {
 783     out->print_cr("   Non-Class:");
 784   }
 785   non_class_cm_stat.print_on(out, scale);
 786 
 787   if (Metaspace::using_class_space()) {
 788     ChunkManagerStatistics class_cm_stat;
 789     Metaspace::chunk_manager_class()->collect_statistics(&class_cm_stat);
 790     out->print_cr("       Class:");
 791     class_cm_stat.print_on(out, scale);
 792   }
 793 
 794   // As a convenience, print a summary of common waste.
 795   out->cr();
 796   out->print("Waste ");
 797   // For all wastages, print percentages from total. As total use the total size of memory committed for metaspace.
 798   const size_t committed_words = committed_bytes() / BytesPerWord;
 799 
 800   out->print("(percentages refer to total committed size ");
 801   print_scaled_words(out, committed_words, scale);
 802   out->print_cr("):");
 803 
 804   // Print space committed but not yet used by any class loader
 805   const size_t unused_words_in_vs = MetaspaceUtils::free_in_vs_bytes() / BytesPerWord;
 806   out->print("              Committed unused: ");
 807   print_scaled_words_and_percentage(out, unused_words_in_vs, committed_words, scale, 6);
 808   out->cr();
 809 
 810   // Print waste for in-use chunks.
 811   UsedChunksStatistics ucs_nonclass = cl._stats_total.nonclass_sm_stats().totals();
 812   UsedChunksStatistics ucs_class = cl._stats_total.class_sm_stats().totals();
 813   UsedChunksStatistics ucs_all;
 814   ucs_all.add(ucs_nonclass);
 815   ucs_all.add(ucs_class);
 816 
 817   out->print("        Waste in chunks in use: ");
 818   print_scaled_words_and_percentage(out, ucs_all.waste(), committed_words, scale, 6);
 819   out->cr();
 820   out->print("         Free in chunks in use: ");
 821   print_scaled_words_and_percentage(out, ucs_all.free(), committed_words, scale, 6);
 822   out->cr();
 823   out->print("     Overhead in chunks in use: ");
 824   print_scaled_words_and_percentage(out, ucs_all.overhead(), committed_words, scale, 6);
 825   out->cr();
 826 
 827   // Print waste in free chunks.
 828   const size_t total_capacity_in_free_chunks =
 829       Metaspace::chunk_manager_metadata()->free_chunks_total_words() +
 830      (Metaspace::using_class_space() ? Metaspace::chunk_manager_class()->free_chunks_total_words() : 0);
 831   out->print("                In free chunks: ");
 832   print_scaled_words_and_percentage(out, total_capacity_in_free_chunks, committed_words, scale, 6);
 833   out->cr();
 834 
 835   // Print waste in deallocated blocks.
 836   const uintx free_blocks_num =
 837       cl._stats_total.nonclass_sm_stats().free_blocks_num() +
 838       cl._stats_total.class_sm_stats().free_blocks_num();
 839   const size_t free_blocks_cap_words =
 840       cl._stats_total.nonclass_sm_stats().free_blocks_cap_words() +
 841       cl._stats_total.class_sm_stats().free_blocks_cap_words();
 842   out->print("Deallocated from chunks in use: ");
 843   print_scaled_words_and_percentage(out, free_blocks_cap_words, committed_words, scale, 6);
 844   out->print(" (" UINTX_FORMAT " blocks)", free_blocks_num);
 845   out->cr();
 846 
 847   // Print total waste.
 848   const size_t total_waste = ucs_all.waste() + ucs_all.free() + ucs_all.overhead() + total_capacity_in_free_chunks
 849       + free_blocks_cap_words + unused_words_in_vs;
 850   out->print("                       -total-: ");
 851   print_scaled_words_and_percentage(out, total_waste, committed_words, scale, 6);
 852   out->cr();
 853 
 854   // Print internal statistics
 855 #ifdef ASSERT
 856   out->cr();
 857   out->cr();
 858   out->print_cr("Internal statistics:");
 859   out->cr();
 860   out->print_cr("Number of allocations: " UINTX_FORMAT ".", g_internal_statistics.num_allocs);
 861   out->print_cr("Number of space births: " UINTX_FORMAT ".", g_internal_statistics.num_metaspace_births);
 862   out->print_cr("Number of space deaths: " UINTX_FORMAT ".", g_internal_statistics.num_metaspace_deaths);
 863   out->print_cr("Number of virtual space node births: " UINTX_FORMAT ".", g_internal_statistics.num_vsnodes_created);
 864   out->print_cr("Number of virtual space node deaths: " UINTX_FORMAT ".", g_internal_statistics.num_vsnodes_purged);
 865   out->print_cr("Number of times virtual space nodes were expanded: " UINTX_FORMAT ".", g_internal_statistics.num_committed_space_expanded);
 866   out->print_cr("Number of deallocations: " UINTX_FORMAT " (" UINTX_FORMAT " external).", g_internal_statistics.num_deallocs, g_internal_statistics.num_external_deallocs);
 867   out->print_cr("Allocations from deallocated blocks: " UINTX_FORMAT ".", g_internal_statistics.num_allocs_from_deallocated_blocks);
 868   out->print_cr("Number of chunks added to freelist: " UINTX_FORMAT ".",
 869                 g_internal_statistics.num_chunks_added_to_freelist);
 870   out->print_cr("Number of chunks removed from freelist: " UINTX_FORMAT ".",
 871                 g_internal_statistics.num_chunks_removed_from_freelist);
 872   out->print_cr("Number of chunk merges: " UINTX_FORMAT ", split-ups: " UINTX_FORMAT ".",
 873                 g_internal_statistics.num_chunk_merges, g_internal_statistics.num_chunk_splits);
 874 
 875   out->cr();
 876 #endif
 877 
 878   // Print some interesting settings
 879   out->cr();
 880   out->cr();
 881   print_basic_switches(out, scale);
 882 
 883   out->cr();
 884   out->print("InitialBootClassLoaderMetaspaceSize: ");
 885   print_human_readable_size(out, InitialBootClassLoaderMetaspaceSize, scale);
 886 
 887   out->cr();
 888   out->cr();
 889 
 890 } // MetaspaceUtils::print_report()
 891 
 892 // Prints an ASCII representation of the given space.
 893 void MetaspaceUtils::print_metaspace_map(outputStream* out, Metaspace::MetadataType mdtype) {
 894   MutexLocker cl(MetaspaceExpand_lock, Mutex::_no_safepoint_check_flag);
 895   const bool for_class = mdtype == Metaspace::ClassType ? true : false;
 896   VirtualSpaceList* const vsl = for_class ? Metaspace::class_space_list() : Metaspace::space_list();
 897   if (vsl != NULL) {
 898     if (for_class) {
 899       if (!Metaspace::using_class_space()) {
 900         out->print_cr("No Class Space.");
 901         return;
 902       }
 903       out->print_raw("---- Metaspace Map (Class Space) ----");
 904     } else {
 905       out->print_raw("---- Metaspace Map (Non-Class Space) ----");
 906     }
 907     // Print legend:
 908     out->cr();
 909     out->print_cr("Chunk Types (uppercase chunks are in use): x-specialized, s-small, m-medium, h-humongous.");
 910     out->cr();
 911     VirtualSpaceList* const vsl = for_class ? Metaspace::class_space_list() : Metaspace::space_list();
 912     vsl->print_map(out);
 913     out->cr();
 914   }
 915 }
 916 
 917 void MetaspaceUtils::verify_free_chunks() {
 918 #ifdef ASSERT
 919   Metaspace::chunk_manager_metadata()->verify(false);
 920   if (Metaspace::using_class_space()) {
 921     Metaspace::chunk_manager_class()->verify(false);
 922   }
 923 #endif
 924 }
 925 
 926 void MetaspaceUtils::verify_metrics() {
 927 #ifdef ASSERT
 928   // Please note: there are time windows where the internal counters are out of sync with
 929   // reality. For example, when a newly created ClassLoaderMetaspace creates its first chunk -
 930   // the ClassLoaderMetaspace is not yet attached to its ClassLoaderData object and hence will
 931   // not be counted when iterating the CLDG. So be careful when you call this method.
 932   ClassLoaderMetaspaceStatistics total_stat;
 933   collect_statistics(&total_stat);
 934   UsedChunksStatistics nonclass_chunk_stat = total_stat.nonclass_sm_stats().totals();
 935   UsedChunksStatistics class_chunk_stat = total_stat.class_sm_stats().totals();
 936 
 937   bool mismatch = false;
 938   for (int i = 0; i < Metaspace::MetadataTypeCount; i ++) {
 939     Metaspace::MetadataType mdtype = (Metaspace::MetadataType)i;
 940     UsedChunksStatistics chunk_stat = total_stat.sm_stats(mdtype).totals();
 941     if (capacity_words(mdtype) != chunk_stat.cap() ||
 942         used_words(mdtype) != chunk_stat.used() ||
 943         overhead_words(mdtype) != chunk_stat.overhead()) {
 944       mismatch = true;
 945       tty->print_cr("MetaspaceUtils::verify_metrics: counter mismatch for mdtype=%u:", mdtype);
 946       tty->print_cr("Expected cap " SIZE_FORMAT ", used " SIZE_FORMAT ", overhead " SIZE_FORMAT ".",
 947                     capacity_words(mdtype), used_words(mdtype), overhead_words(mdtype));
 948       tty->print_cr("Got cap " SIZE_FORMAT ", used " SIZE_FORMAT ", overhead " SIZE_FORMAT ".",
 949                     chunk_stat.cap(), chunk_stat.used(), chunk_stat.overhead());
 950       tty->flush();
 951     }
 952   }
 953   assert(mismatch == false, "MetaspaceUtils::verify_metrics: counter mismatch.");
 954 #endif
 955 }
 956 
 957 // Metaspace methods
 958 
 959 size_t Metaspace::_first_chunk_word_size = 0;
 960 size_t Metaspace::_first_class_chunk_word_size = 0;
 961 
 962 size_t Metaspace::_commit_alignment = 0;
 963 size_t Metaspace::_reserve_alignment = 0;
 964 
 965 VirtualSpaceList* Metaspace::_space_list = NULL;
 966 VirtualSpaceList* Metaspace::_class_space_list = NULL;
 967 
 968 ChunkManager* Metaspace::_chunk_manager_metadata = NULL;
 969 ChunkManager* Metaspace::_chunk_manager_class = NULL;
 970 
 971 bool Metaspace::_initialized = false;
 972 
 973 #define VIRTUALSPACEMULTIPLIER 2
 974 
 975 #ifdef _LP64
 976 static const uint64_t UnscaledClassSpaceMax = (uint64_t(max_juint) + 1);
 977 
 978 void Metaspace::set_narrow_klass_base_and_shift(ReservedSpace metaspace_rs, address cds_base) {
 979   assert(!DumpSharedSpaces, "narrow_klass is set by MetaspaceShared class.");
 980   // Figure out the narrow_klass_base and the narrow_klass_shift.  The
 981   // narrow_klass_base is the lower of the metaspace base and the cds base
 982   // (if cds is enabled).  The narrow_klass_shift depends on the distance
 983   // between the lower base and higher address.
 984   address lower_base = (address)metaspace_rs.base();
 985   address higher_address = (address)metaspace_rs.end();
 986   if (cds_base != NULL) {
 987     assert(UseSharedSpaces, "must be");
 988     lower_base = MIN2(lower_base, cds_base);
 989   } else {
 990     uint64_t klass_encoding_max = UnscaledClassSpaceMax << LogKlassAlignmentInBytes;
 991     // If compressed class space fits in lower 32G, we don't need a base.
 992     if (higher_address <= (address)klass_encoding_max) {
 993       lower_base = 0; // Effectively lower base is zero.
 994     }
 995   }
 996 
 997   CompressedKlassPointers::set_base(lower_base);
 998 
 999   // CDS uses LogKlassAlignmentInBytes for narrow_klass_shift. See
1000   // MetaspaceShared::initialize_dumptime_shared_and_meta_spaces() for
1001   // how dump time narrow_klass_shift is set. Although, CDS can work
1002   // with zero-shift mode also, to be consistent with AOT it uses
1003   // LogKlassAlignmentInBytes for klass shift so archived java heap objects
1004   // can be used at same time as AOT code.
1005   if (!UseSharedSpaces
1006       && (uint64_t)(higher_address - lower_base) <= UnscaledClassSpaceMax) {
1007     CompressedKlassPointers::set_shift(0);
1008   } else {
1009     CompressedKlassPointers::set_shift(LogKlassAlignmentInBytes);
1010   }
1011   AOTLoader::set_narrow_klass_shift();
1012 }
1013 
1014 // Try to allocate the metaspace at the requested addr.
1015 void Metaspace::allocate_metaspace_compressed_klass_ptrs(ReservedSpace metaspace_rs, char* requested_addr, address cds_base) {
1016   assert(!DumpSharedSpaces, "compress klass space is allocated by MetaspaceShared class.");
1017   assert(using_class_space(), "called improperly");
1018   assert(UseCompressedClassPointers, "Only use with CompressedKlassPtrs");
1019   assert(compressed_class_space_size() < KlassEncodingMetaspaceMax,
1020          "Metaspace size is too big");
1021   assert_is_aligned(requested_addr, _reserve_alignment);
1022   assert_is_aligned(cds_base, _reserve_alignment);
1023   assert_is_aligned(compressed_class_space_size(), _reserve_alignment);
1024 
1025   // Don't use large pages for the class space.
1026   bool large_pages = false;
1027 
1028  if (metaspace_rs.is_reserved()) {
1029    // CDS should have already reserved the space.
1030    assert(requested_addr == NULL, "not used");
1031    assert(cds_base != NULL, "CDS should have already reserved the memory space");
1032  } else {
1033    assert(cds_base == NULL, "must be");
1034 #if !(defined(AARCH64) || defined(AIX))
1035   metaspace_rs = ReservedSpace(compressed_class_space_size(), _reserve_alignment,
1036                                large_pages, requested_addr);
1037 #else // AARCH64
1038   // Our compressed klass pointers may fit nicely into the lower 32
1039   // bits.
1040   if ((uint64_t)requested_addr + compressed_class_space_size() < 4*G) {
1041     metaspace_rs = ReservedSpace(compressed_class_space_size(),
1042                                  _reserve_alignment,
1043                                  large_pages,
1044                                  requested_addr);
1045   }
1046 
1047   if (! metaspace_rs.is_reserved()) {
1048     // Aarch64: Try to align metaspace so that we can decode a compressed
1049     // klass with a single MOVK instruction.  We can do this iff the
1050     // compressed class base is a multiple of 4G.
1051     // Aix: Search for a place where we can find memory. If we need to load
1052     // the base, 4G alignment is helpful, too.
1053     size_t increment = AARCH64_ONLY(4*)G;
1054     for (char *a = align_up(requested_addr, increment);
1055          a < (char*)(1024*G);
1056          a += increment) {
1057       if (a == (char *)(32*G)) {
1058         // Go faster from here on. Zero-based is no longer possible.
1059         increment = 4*G;
1060       }
1061 
1062       metaspace_rs = ReservedSpace(compressed_class_space_size(),
1063                                    _reserve_alignment,
1064                                    large_pages,
1065                                    a);
1066       if (metaspace_rs.is_reserved())
1067         break;
1068     }
1069   }
1070 #endif // AARCH64
1071  }
1072 
1073   if (!metaspace_rs.is_reserved()) {
1074     assert(cds_base == NULL, "CDS should have already reserved the memory space");
1075     // If no successful allocation then try to allocate the space anywhere.  If
1076     // that fails then OOM doom.  At this point we cannot try allocating the
1077     // metaspace as if UseCompressedClassPointers is off because too much
1078     // initialization has happened that depends on UseCompressedClassPointers.
1079     // So, UseCompressedClassPointers cannot be turned off at this point.
1080     metaspace_rs = ReservedSpace(compressed_class_space_size(),
1081                                  _reserve_alignment, large_pages);
1082     if (!metaspace_rs.is_reserved()) {
1083       vm_exit_during_initialization(err_msg("Could not allocate metaspace: " SIZE_FORMAT " bytes",
1084                                             compressed_class_space_size()));
1085     }
1086   }
1087 
1088   if (cds_base == NULL) {
1089     // If we got here then the metaspace got allocated.
1090     MemTracker::record_virtual_memory_type((address)metaspace_rs.base(), mtClass);
1091   }
1092 
1093   set_narrow_klass_base_and_shift(metaspace_rs, cds_base);
1094 
1095   initialize_class_space(metaspace_rs);
1096 
1097   LogTarget(Trace, gc, metaspace) lt;
1098   if (lt.is_enabled()) {
1099     ResourceMark rm;
1100     LogStream ls(lt);
1101     print_compressed_class_space(&ls, requested_addr);
1102   }
1103 }
1104 
1105 void Metaspace::print_compressed_class_space(outputStream* st, const char* requested_addr) {
1106   st->print_cr("Narrow klass base: " PTR_FORMAT ", Narrow klass shift: %d",
1107                p2i(CompressedKlassPointers::base()), CompressedKlassPointers::shift());
1108   if (_class_space_list != NULL) {
1109     address base = (address)_class_space_list->current_virtual_space()->bottom();
1110     st->print("Compressed class space size: " SIZE_FORMAT " Address: " PTR_FORMAT,
1111                  compressed_class_space_size(), p2i(base));
1112     if (requested_addr != 0) {
1113       st->print(" Req Addr: " PTR_FORMAT, p2i(requested_addr));
1114     }
1115     st->cr();
1116   }
1117 }
1118 
1119 // For UseCompressedClassPointers the class space is reserved above the top of
1120 // the Java heap.  The argument passed in is at the base of the compressed space.
1121 void Metaspace::initialize_class_space(ReservedSpace rs) {
1122   // The reserved space size may be bigger because of alignment, esp with UseLargePages
1123   assert(rs.size() >= CompressedClassSpaceSize,
1124          SIZE_FORMAT " != " SIZE_FORMAT, rs.size(), CompressedClassSpaceSize);
1125   assert(using_class_space(), "Must be using class space");
1126   _class_space_list = new VirtualSpaceList(rs);
1127   _chunk_manager_class = new ChunkManager(true/*is_class*/);
1128 
1129   if (!_class_space_list->initialization_succeeded()) {
1130     vm_exit_during_initialization("Failed to setup compressed class space virtual space list.");
1131   }
1132 }
1133 
1134 #endif
1135 
1136 void Metaspace::ergo_initialize() {
1137   if (DumpSharedSpaces) {
1138     // Using large pages when dumping the shared archive is currently not implemented.
1139     FLAG_SET_ERGO(UseLargePagesInMetaspace, false);
1140   }
1141 
1142   size_t page_size = os::vm_page_size();
1143   if (UseLargePages && UseLargePagesInMetaspace) {
1144     page_size = os::large_page_size();
1145   }
1146 
1147   _commit_alignment  = page_size;
1148   _reserve_alignment = MAX2(page_size, (size_t)os::vm_allocation_granularity());
1149 
1150   // Do not use FLAG_SET_ERGO to update MaxMetaspaceSize, since this will
1151   // override if MaxMetaspaceSize was set on the command line or not.
1152   // This information is needed later to conform to the specification of the
1153   // java.lang.management.MemoryUsage API.
1154   //
1155   // Ideally, we would be able to set the default value of MaxMetaspaceSize in
1156   // globals.hpp to the aligned value, but this is not possible, since the
1157   // alignment depends on other flags being parsed.
1158   MaxMetaspaceSize = align_down_bounded(MaxMetaspaceSize, _reserve_alignment);
1159 
1160   if (MetaspaceSize > MaxMetaspaceSize) {
1161     MetaspaceSize = MaxMetaspaceSize;
1162   }
1163 
1164   MetaspaceSize = align_down_bounded(MetaspaceSize, _commit_alignment);
1165 
1166   assert(MetaspaceSize <= MaxMetaspaceSize, "MetaspaceSize should be limited by MaxMetaspaceSize");
1167 
1168   MinMetaspaceExpansion = align_down_bounded(MinMetaspaceExpansion, _commit_alignment);
1169   MaxMetaspaceExpansion = align_down_bounded(MaxMetaspaceExpansion, _commit_alignment);
1170 
1171   CompressedClassSpaceSize = align_down_bounded(CompressedClassSpaceSize, _reserve_alignment);
1172 
1173   // Initial virtual space size will be calculated at global_initialize()
1174   size_t min_metaspace_sz =
1175       VIRTUALSPACEMULTIPLIER * InitialBootClassLoaderMetaspaceSize;
1176   if (UseCompressedClassPointers) {
1177     if ((min_metaspace_sz + CompressedClassSpaceSize) >  MaxMetaspaceSize) {
1178       if (min_metaspace_sz >= MaxMetaspaceSize) {
1179         vm_exit_during_initialization("MaxMetaspaceSize is too small.");
1180       } else {
1181         FLAG_SET_ERGO(CompressedClassSpaceSize,
1182                       MaxMetaspaceSize - min_metaspace_sz);
1183       }
1184     }
1185   } else if (min_metaspace_sz >= MaxMetaspaceSize) {
1186     FLAG_SET_ERGO(InitialBootClassLoaderMetaspaceSize,
1187                   min_metaspace_sz);
1188   }
1189 
1190   set_compressed_class_space_size(CompressedClassSpaceSize);
1191 }
1192 
1193 void Metaspace::global_initialize() {
1194   MetaspaceGC::initialize();
1195 
1196   bool class_space_inited = false;
1197 #if INCLUDE_CDS
1198   if (DumpSharedSpaces) {
1199     MetaspaceShared::initialize_dumptime_shared_and_meta_spaces();
1200     class_space_inited = true;
1201   } else if (UseSharedSpaces) {
1202     // If any of the archived space fails to map, UseSharedSpaces
1203     // is reset to false.
1204     MetaspaceShared::initialize_runtime_shared_and_meta_spaces();
1205     class_space_inited = UseSharedSpaces;
1206   }
1207 
1208   if (DynamicDumpSharedSpaces && !UseSharedSpaces) {
1209     vm_exit_during_initialization("DynamicDumpSharedSpaces is unsupported when base CDS archive is not loaded", NULL);
1210   }
1211 #endif // INCLUDE_CDS
1212 
1213 #ifdef _LP64
1214   if (using_class_space() && !class_space_inited) {
1215     char* base = (char*)align_up(CompressedOops::end(), _reserve_alignment);
1216     ReservedSpace dummy;
1217     allocate_metaspace_compressed_klass_ptrs(dummy, base, 0);
1218   }
1219 #endif
1220 
1221   // Initialize these before initializing the VirtualSpaceList
1222   _first_chunk_word_size = InitialBootClassLoaderMetaspaceSize / BytesPerWord;
1223   _first_chunk_word_size = align_word_size_up(_first_chunk_word_size);
1224   // Make the first class chunk bigger than a medium chunk so it's not put
1225   // on the medium chunk list.   The next chunk will be small and progress
1226   // from there.  This size calculated by -version.
1227   _first_class_chunk_word_size = MIN2((size_t)MediumChunk*6,
1228                                      (CompressedClassSpaceSize/BytesPerWord)*2);
1229   _first_class_chunk_word_size = align_word_size_up(_first_class_chunk_word_size);
1230   // Arbitrarily set the initial virtual space to a multiple
1231   // of the boot class loader size.
1232   size_t word_size = VIRTUALSPACEMULTIPLIER * _first_chunk_word_size;
1233   word_size = align_up(word_size, Metaspace::reserve_alignment_words());
1234 
1235   // Initialize the list of virtual spaces.
1236   _space_list = new VirtualSpaceList(word_size);
1237   _chunk_manager_metadata = new ChunkManager(false/*metaspace*/);
1238 
1239   if (!_space_list->initialization_succeeded()) {
1240     vm_exit_during_initialization("Unable to setup metadata virtual space list.", NULL);
1241   }
1242 
1243   _tracer = new MetaspaceTracer();
1244 
1245   _initialized = true;
1246 
1247 }
1248 
1249 void Metaspace::post_initialize() {
1250   MetaspaceGC::post_initialize();
1251 }
1252 
1253 void Metaspace::verify_global_initialization() {
1254   assert(space_list() != NULL, "Metadata VirtualSpaceList has not been initialized");
1255   assert(chunk_manager_metadata() != NULL, "Metadata ChunkManager has not been initialized");
1256 
1257   if (using_class_space()) {
1258     assert(class_space_list() != NULL, "Class VirtualSpaceList has not been initialized");
1259     assert(chunk_manager_class() != NULL, "Class ChunkManager has not been initialized");
1260   }
1261 }
1262 
1263 size_t Metaspace::align_word_size_up(size_t word_size) {
1264   size_t byte_size = word_size * wordSize;
1265   return ReservedSpace::allocation_align_size_up(byte_size) / wordSize;
1266 }
1267 
1268 MetaWord* Metaspace::allocate(ClassLoaderData* loader_data, size_t word_size,
1269                               MetaspaceObj::Type type, TRAPS) {
1270   assert(!_frozen, "sanity");
1271   assert(!(DumpSharedSpaces && THREAD->is_VM_thread()), "sanity");
1272 
1273   if (HAS_PENDING_EXCEPTION) {
1274     assert(false, "Should not allocate with exception pending");
1275     return NULL;  // caller does a CHECK_NULL too
1276   }
1277 
1278   assert(loader_data != NULL, "Should never pass around a NULL loader_data. "
1279         "ClassLoaderData::the_null_class_loader_data() should have been used.");
1280 
1281   MetadataType mdtype = (type == MetaspaceObj::ClassType) ? ClassType : NonClassType;
1282 
1283   // Try to allocate metadata.
1284   MetaWord* result = loader_data->metaspace_non_null()->allocate(word_size, mdtype);
1285 
1286   if (result == NULL) {
1287     tracer()->report_metaspace_allocation_failure(loader_data, word_size, type, mdtype);
1288 
1289     // Allocation failed.
1290     if (is_init_completed()) {
1291       // Only start a GC if the bootstrapping has completed.
1292       // Try to clean out some heap memory and retry. This can prevent premature
1293       // expansion of the metaspace.
1294       result = Universe::heap()->satisfy_failed_metadata_allocation(loader_data, word_size, mdtype);
1295     }
1296   }
1297 
1298   if (result == NULL) {
1299     if (DumpSharedSpaces) {
1300       // CDS dumping keeps loading classes, so if we hit an OOM we probably will keep hitting OOM.
1301       // We should abort to avoid generating a potentially bad archive.
1302       vm_exit_during_cds_dumping(err_msg("Failed allocating metaspace object type %s of size " SIZE_FORMAT ". CDS dump aborted.",
1303           MetaspaceObj::type_name(type), word_size * BytesPerWord),
1304         err_msg("Please increase MaxMetaspaceSize (currently " SIZE_FORMAT " bytes).", MaxMetaspaceSize));
1305     }
1306     report_metadata_oome(loader_data, word_size, type, mdtype, THREAD);
1307     assert(HAS_PENDING_EXCEPTION, "sanity");
1308     return NULL;
1309   }
1310 
1311   // Zero initialize.
1312   Copy::fill_to_words((HeapWord*)result, word_size, 0);
1313 
1314   return result;
1315 }
1316 
1317 void Metaspace::report_metadata_oome(ClassLoaderData* loader_data, size_t word_size, MetaspaceObj::Type type, MetadataType mdtype, TRAPS) {
1318   tracer()->report_metadata_oom(loader_data, word_size, type, mdtype);
1319 
1320   // If result is still null, we are out of memory.
1321   Log(gc, metaspace, freelist, oom) log;
1322   if (log.is_info()) {
1323     log.info("Metaspace (%s) allocation failed for size " SIZE_FORMAT,
1324              is_class_space_allocation(mdtype) ? "class" : "data", word_size);
1325     ResourceMark rm;
1326     if (log.is_debug()) {
1327       if (loader_data->metaspace_or_null() != NULL) {
1328         LogStream ls(log.debug());
1329         loader_data->print_value_on(&ls);
1330       }
1331     }
1332     LogStream ls(log.info());
1333     // In case of an OOM, log out a short but still useful report.
1334     MetaspaceUtils::print_basic_report(&ls, 0);
1335   }
1336 
1337   bool out_of_compressed_class_space = false;
1338   if (is_class_space_allocation(mdtype)) {
1339     ClassLoaderMetaspace* metaspace = loader_data->metaspace_non_null();
1340     out_of_compressed_class_space =
1341       MetaspaceUtils::committed_bytes(Metaspace::ClassType) +
1342       (metaspace->class_chunk_size(word_size) * BytesPerWord) >
1343       CompressedClassSpaceSize;
1344   }
1345 
1346   // -XX:+HeapDumpOnOutOfMemoryError and -XX:OnOutOfMemoryError support
1347   const char* space_string = out_of_compressed_class_space ?
1348     "Compressed class space" : "Metaspace";
1349 
1350   report_java_out_of_memory(space_string);
1351 
1352   if (JvmtiExport::should_post_resource_exhausted()) {
1353     JvmtiExport::post_resource_exhausted(
1354         JVMTI_RESOURCE_EXHAUSTED_OOM_ERROR,
1355         space_string);
1356   }
1357 
1358   if (!is_init_completed()) {
1359     vm_exit_during_initialization("OutOfMemoryError", space_string);
1360   }
1361 
1362   if (out_of_compressed_class_space) {
1363     THROW_OOP(Universe::out_of_memory_error_class_metaspace());
1364   } else {
1365     THROW_OOP(Universe::out_of_memory_error_metaspace());
1366   }
1367 }
1368 
1369 const char* Metaspace::metadata_type_name(Metaspace::MetadataType mdtype) {
1370   switch (mdtype) {
1371     case Metaspace::ClassType: return "Class";
1372     case Metaspace::NonClassType: return "Metadata";
1373     default:
1374       assert(false, "Got bad mdtype: %d", (int) mdtype);
1375       return NULL;
1376   }
1377 }
1378 
1379 void Metaspace::purge(MetadataType mdtype) {
1380   get_space_list(mdtype)->purge(get_chunk_manager(mdtype));
1381 }
1382 
1383 void Metaspace::purge() {
1384   MutexLocker cl(MetaspaceExpand_lock,
1385                  Mutex::_no_safepoint_check_flag);
1386   purge(NonClassType);
1387   if (using_class_space()) {
1388     purge(ClassType);
1389   }
1390 }
1391 
1392 bool Metaspace::contains(const void* ptr) {
1393   if (MetaspaceShared::is_in_shared_metaspace(ptr)) {
1394     return true;
1395   }
1396   return contains_non_shared(ptr);
1397 }
1398 
1399 bool Metaspace::contains_non_shared(const void* ptr) {
1400   if (using_class_space() && get_space_list(ClassType)->contains(ptr)) {
1401      return true;
1402   }
1403 
1404   return get_space_list(NonClassType)->contains(ptr);
1405 }
1406 
1407 // ClassLoaderMetaspace
1408 
1409 ClassLoaderMetaspace::ClassLoaderMetaspace(Mutex* lock, Metaspace::MetaspaceType type)
1410   : _space_type(type)
1411   , _lock(lock)
1412   , _vsm(NULL)
1413   , _class_vsm(NULL)
1414 {
1415   initialize(lock, type);
1416 }
1417 
1418 ClassLoaderMetaspace::~ClassLoaderMetaspace() {
1419   Metaspace::assert_not_frozen();
1420   DEBUG_ONLY(Atomic::inc(&g_internal_statistics.num_metaspace_deaths));
1421   delete _vsm;
1422   if (Metaspace::using_class_space()) {
1423     delete _class_vsm;
1424   }
1425 }
1426 
1427 void ClassLoaderMetaspace::initialize_first_chunk(Metaspace::MetaspaceType type, Metaspace::MetadataType mdtype) {
1428   Metachunk* chunk = get_initialization_chunk(type, mdtype);
1429   if (chunk != NULL) {
1430     // Add to this manager's list of chunks in use and make it the current_chunk().
1431     get_space_manager(mdtype)->add_chunk(chunk, true);
1432   }
1433 }
1434 
1435 Metachunk* ClassLoaderMetaspace::get_initialization_chunk(Metaspace::MetaspaceType type, Metaspace::MetadataType mdtype) {
1436   size_t chunk_word_size = get_space_manager(mdtype)->get_initial_chunk_size(type);
1437 
1438   // Get a chunk from the chunk freelist
1439   Metachunk* chunk = Metaspace::get_chunk_manager(mdtype)->chunk_freelist_allocate(chunk_word_size);
1440 
1441   if (chunk == NULL) {
1442     chunk = Metaspace::get_space_list(mdtype)->get_new_chunk(chunk_word_size,
1443                                                   get_space_manager(mdtype)->medium_chunk_bunch());
1444   }
1445 
1446   return chunk;
1447 }
1448 
1449 void ClassLoaderMetaspace::initialize(Mutex* lock, Metaspace::MetaspaceType type) {
1450   Metaspace::verify_global_initialization();
1451 
1452   DEBUG_ONLY(Atomic::inc(&g_internal_statistics.num_metaspace_births));
1453 
1454   // Allocate SpaceManager for metadata objects.
1455   _vsm = new SpaceManager(Metaspace::NonClassType, type, lock);
1456 
1457   if (Metaspace::using_class_space()) {
1458     // Allocate SpaceManager for classes.
1459     _class_vsm = new SpaceManager(Metaspace::ClassType, type, lock);
1460   }
1461 
1462   MutexLocker cl(MetaspaceExpand_lock, Mutex::_no_safepoint_check_flag);
1463 
1464   // Allocate chunk for metadata objects
1465   initialize_first_chunk(type, Metaspace::NonClassType);
1466 
1467   // Allocate chunk for class metadata objects
1468   if (Metaspace::using_class_space()) {
1469     initialize_first_chunk(type, Metaspace::ClassType);
1470   }
1471 }
1472 
1473 MetaWord* ClassLoaderMetaspace::allocate(size_t word_size, Metaspace::MetadataType mdtype) {
1474   Metaspace::assert_not_frozen();
1475 
1476   DEBUG_ONLY(Atomic::inc(&g_internal_statistics.num_allocs));
1477 
1478   // Don't use class_vsm() unless UseCompressedClassPointers is true.
1479   if (Metaspace::is_class_space_allocation(mdtype)) {
1480     return  class_vsm()->allocate(word_size);
1481   } else {
1482     return  vsm()->allocate(word_size);
1483   }
1484 }
1485 
1486 MetaWord* ClassLoaderMetaspace::expand_and_allocate(size_t word_size, Metaspace::MetadataType mdtype) {
1487   Metaspace::assert_not_frozen();
1488   size_t delta_bytes = MetaspaceGC::delta_capacity_until_GC(word_size * BytesPerWord);
1489   assert(delta_bytes > 0, "Must be");
1490 
1491   size_t before = 0;
1492   size_t after = 0;
1493   bool can_retry = true;
1494   MetaWord* res;
1495   bool incremented;
1496 
1497   // Each thread increments the HWM at most once. Even if the thread fails to increment
1498   // the HWM, an allocation is still attempted. This is because another thread must then
1499   // have incremented the HWM and therefore the allocation might still succeed.
1500   do {
1501     incremented = MetaspaceGC::inc_capacity_until_GC(delta_bytes, &after, &before, &can_retry);
1502     res = allocate(word_size, mdtype);
1503   } while (!incremented && res == NULL && can_retry);
1504 
1505   if (incremented) {
1506     Metaspace::tracer()->report_gc_threshold(before, after,
1507                                   MetaspaceGCThresholdUpdater::ExpandAndAllocate);
1508     log_trace(gc, metaspace)("Increase capacity to GC from " SIZE_FORMAT " to " SIZE_FORMAT, before, after);
1509   }
1510 
1511   return res;
1512 }
1513 
1514 size_t ClassLoaderMetaspace::allocated_blocks_bytes() const {
1515   return (vsm()->used_words() +
1516       (Metaspace::using_class_space() ? class_vsm()->used_words() : 0)) * BytesPerWord;
1517 }
1518 
1519 size_t ClassLoaderMetaspace::allocated_chunks_bytes() const {
1520   return (vsm()->capacity_words() +
1521       (Metaspace::using_class_space() ? class_vsm()->capacity_words() : 0)) * BytesPerWord;
1522 }
1523 
1524 void ClassLoaderMetaspace::deallocate(MetaWord* ptr, size_t word_size, bool is_class) {
1525   Metaspace::assert_not_frozen();
1526   assert(!SafepointSynchronize::is_at_safepoint()
1527          || Thread::current()->is_VM_thread(), "should be the VM thread");
1528 
1529   DEBUG_ONLY(Atomic::inc(&g_internal_statistics.num_external_deallocs));
1530 
1531   MutexLocker ml(vsm()->lock(), Mutex::_no_safepoint_check_flag);
1532 
1533   if (is_class && Metaspace::using_class_space()) {
1534     class_vsm()->deallocate(ptr, word_size);
1535   } else {
1536     vsm()->deallocate(ptr, word_size);
1537   }
1538 }
1539 
1540 size_t ClassLoaderMetaspace::class_chunk_size(size_t word_size) {
1541   assert(Metaspace::using_class_space(), "Has to use class space");
1542   return class_vsm()->calc_chunk_size(word_size);
1543 }
1544 
1545 void ClassLoaderMetaspace::print_on(outputStream* out) const {
1546   // Print both class virtual space counts and metaspace.
1547   if (Verbose) {
1548     vsm()->print_on(out);
1549     if (Metaspace::using_class_space()) {
1550       class_vsm()->print_on(out);
1551     }
1552   }
1553 }
1554 
1555 void ClassLoaderMetaspace::verify() {
1556   vsm()->verify();
1557   if (Metaspace::using_class_space()) {
1558     class_vsm()->verify();
1559   }
1560 }
1561 
1562 void ClassLoaderMetaspace::add_to_statistics_locked(ClassLoaderMetaspaceStatistics* out) const {
1563   assert_lock_strong(lock());
1564   vsm()->add_to_statistics_locked(&out->nonclass_sm_stats());
1565   if (Metaspace::using_class_space()) {
1566     class_vsm()->add_to_statistics_locked(&out->class_sm_stats());
1567   }
1568 }
1569 
1570 void ClassLoaderMetaspace::add_to_statistics(ClassLoaderMetaspaceStatistics* out) const {
1571   MutexLocker cl(lock(), Mutex::_no_safepoint_check_flag);
1572   add_to_statistics_locked(out);
1573 }
1574 
1575 /////////////// Unit tests ///////////////
1576 
1577 struct chunkmanager_statistics_t {
1578   int num_specialized_chunks;
1579   int num_small_chunks;
1580   int num_medium_chunks;
1581   int num_humongous_chunks;
1582 };
1583 
1584 extern void test_metaspace_retrieve_chunkmanager_statistics(Metaspace::MetadataType mdType, chunkmanager_statistics_t* out) {
1585   ChunkManager* const chunk_manager = Metaspace::get_chunk_manager(mdType);
1586   ChunkManagerStatistics stat;
1587   chunk_manager->collect_statistics(&stat);
1588   out->num_specialized_chunks = (int)stat.chunk_stats(SpecializedIndex).num();
1589   out->num_small_chunks = (int)stat.chunk_stats(SmallIndex).num();
1590   out->num_medium_chunks = (int)stat.chunk_stats(MediumIndex).num();
1591   out->num_humongous_chunks = (int)stat.chunk_stats(HumongousIndex).num();
1592 }
1593 
1594 struct chunk_geometry_t {
1595   size_t specialized_chunk_word_size;
1596   size_t small_chunk_word_size;
1597   size_t medium_chunk_word_size;
1598 };
1599 
1600 extern void test_metaspace_retrieve_chunk_geometry(Metaspace::MetadataType mdType, chunk_geometry_t* out) {
1601   if (mdType == Metaspace::NonClassType) {
1602     out->specialized_chunk_word_size = SpecializedChunk;
1603     out->small_chunk_word_size = SmallChunk;
1604     out->medium_chunk_word_size = MediumChunk;
1605   } else {
1606     out->specialized_chunk_word_size = ClassSpecializedChunk;
1607     out->small_chunk_word_size = ClassSmallChunk;
1608     out->medium_chunk_word_size = ClassMediumChunk;
1609   }
1610 }