1 /*
   2  * Copyright (c) 2003, 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 "classfile/systemDictionary.hpp"
  27 #include "classfile/vmSymbols.hpp"
  28 #include "oops/oop.inline.hpp"
  29 #include "runtime/handles.inline.hpp"
  30 #include "runtime/javaCalls.hpp"
  31 #include "runtime/orderAccess.inline.hpp"
  32 #include "services/lowMemoryDetector.hpp"
  33 #include "services/management.hpp"
  34 #include "services/memoryManager.hpp"
  35 #include "services/memoryPool.hpp"
  36 #include "services/memoryService.hpp"
  37 #include "services/gcNotifier.hpp"
  38 #include "utilities/dtrace.hpp"
  39 
  40 #ifndef USDT2
  41 HS_DTRACE_PROBE_DECL8(hotspot, mem__pool__gc__begin, char*, int, char*, int,
  42   size_t, size_t, size_t, size_t);
  43 HS_DTRACE_PROBE_DECL8(hotspot, mem__pool__gc__end, char*, int, char*, int,
  44   size_t, size_t, size_t, size_t);
  45 #endif /* !USDT2 */
  46 
  47 MemoryManager::MemoryManager() {
  48   _num_pools = 0;
  49   (void)const_cast<instanceOop&>(_memory_mgr_obj = instanceOop(NULL));
  50 }
  51 
  52 int MemoryManager::add_pool(MemoryPool* pool) {
  53   int index = _num_pools;
  54   assert(index < MemoryManager::max_num_pools, "_num_pools exceeds the max");
  55   if (index < MemoryManager::max_num_pools) {
  56     _pools[index] = pool;
  57     _num_pools++;
  58   }
  59   pool->add_manager(this);
  60   return index;
  61 }
  62 
  63 MemoryManager* MemoryManager::get_code_cache_memory_manager() {
  64   return (MemoryManager*) new CodeCacheMemoryManager();
  65 }
  66 
  67 MemoryManager* MemoryManager::get_metaspace_memory_manager() {
  68   return (MemoryManager*) new MetaspaceMemoryManager();
  69 }
  70 
  71 GCMemoryManager* MemoryManager::get_copy_memory_manager() {
  72   return (GCMemoryManager*) new CopyMemoryManager();
  73 }
  74 
  75 GCMemoryManager* MemoryManager::get_msc_memory_manager() {
  76   return (GCMemoryManager*) new MSCMemoryManager();
  77 }
  78 
  79 GCMemoryManager* MemoryManager::get_parnew_memory_manager() {
  80   return (GCMemoryManager*) new ParNewMemoryManager();
  81 }
  82 
  83 GCMemoryManager* MemoryManager::get_cms_memory_manager() {
  84   return (GCMemoryManager*) new CMSMemoryManager();
  85 }
  86 
  87 GCMemoryManager* MemoryManager::get_psScavenge_memory_manager() {
  88   return (GCMemoryManager*) new PSScavengeMemoryManager();
  89 }
  90 
  91 GCMemoryManager* MemoryManager::get_psMarkSweep_memory_manager() {
  92   return (GCMemoryManager*) new PSMarkSweepMemoryManager();
  93 }
  94 
  95 GCMemoryManager* MemoryManager::get_g1YoungGen_memory_manager() {
  96   return (GCMemoryManager*) new G1YoungGenMemoryManager();
  97 }
  98 
  99 GCMemoryManager* MemoryManager::get_g1OldGen_memory_manager() {
 100   return (GCMemoryManager*) new G1OldGenMemoryManager();
 101 }
 102 
 103 instanceOop MemoryManager::get_memory_manager_instance(TRAPS) {
 104   // Must do an acquire so as to force ordering of subsequent
 105   // loads from anything _memory_mgr_obj points to or implies.
 106   instanceOop mgr_obj = (instanceOop)OrderAccess::load_ptr_acquire(&_memory_mgr_obj);
 107   if (mgr_obj == NULL) {
 108     // It's ok for more than one thread to execute the code up to the locked region.
 109     // Extra manager instances will just be gc'ed.
 110     Klass* k = Management::sun_management_ManagementFactory_klass(CHECK_0);
 111     instanceKlassHandle ik(THREAD, k);
 112 
 113     Handle mgr_name = java_lang_String::create_from_str(name(), CHECK_0);
 114 
 115     JavaValue result(T_OBJECT);
 116     JavaCallArguments args;
 117     args.push_oop(mgr_name);    // Argument 1
 118 
 119     Symbol* method_name = NULL;
 120     Symbol* signature = NULL;
 121     if (is_gc_memory_manager()) {
 122       method_name = vmSymbols::createGarbageCollector_name();
 123       signature = vmSymbols::createGarbageCollector_signature();
 124       args.push_oop(Handle());      // Argument 2 (for future extension)
 125     } else {
 126       method_name = vmSymbols::createMemoryManager_name();
 127       signature = vmSymbols::createMemoryManager_signature();
 128     }
 129 
 130     JavaCalls::call_static(&result,
 131                            ik,
 132                            method_name,
 133                            signature,
 134                            &args,
 135                            CHECK_0);
 136 
 137     instanceOop m = (instanceOop) result.get_jobject();
 138     instanceHandle mgr(THREAD, m);
 139 
 140     {
 141       // Get lock before setting _memory_mgr_obj
 142       // since another thread may have created the instance
 143       MutexLocker ml(Management_lock);
 144 
 145       // Check if another thread has created the management object.  We reload
 146       // _memory_mgr_obj here because some other thread may have initialized
 147       // it while we were executing the code before the lock.
 148       //
 149       // The lock has done an acquire, so the load can't float above it, but
 150       // we need to do a load_acquire as above.
 151       mgr_obj = (instanceOop)OrderAccess::load_ptr_acquire(&_memory_mgr_obj);
 152       if (mgr_obj != NULL) {
 153          return mgr_obj;
 154       }
 155 
 156       // Get the address of the object we created via call_special.
 157       mgr_obj = mgr();
 158 
 159       // Use store barrier to make sure the memory accesses associated
 160       // with creating the management object are visible before publishing
 161       // its address.  The unlock will publish the store to _memory_mgr_obj
 162       // because it does a release first.
 163       OrderAccess::release_store_ptr(&_memory_mgr_obj, mgr_obj);
 164     }
 165   }
 166 
 167   return mgr_obj;
 168 }
 169 
 170 void MemoryManager::oops_do(OopClosure* f) {
 171   f->do_oop((oop*) &_memory_mgr_obj);
 172 }
 173 
 174 GCStatInfo::GCStatInfo(int num_pools) {
 175   // initialize the arrays for memory usage
 176   _before_gc_usage_array = (MemoryUsage*) NEW_C_HEAP_ARRAY(MemoryUsage, num_pools, mtInternal);
 177   _after_gc_usage_array  = (MemoryUsage*) NEW_C_HEAP_ARRAY(MemoryUsage, num_pools, mtInternal);
 178   _usage_array_size = num_pools;
 179   clear();
 180 }
 181 
 182 GCStatInfo::~GCStatInfo() {
 183   FREE_C_HEAP_ARRAY(MemoryUsage*, _before_gc_usage_array, mtInternal);
 184   FREE_C_HEAP_ARRAY(MemoryUsage*, _after_gc_usage_array, mtInternal);
 185 }
 186 
 187 void GCStatInfo::set_gc_usage(int pool_index, MemoryUsage usage, bool before_gc) {
 188   MemoryUsage* gc_usage_array;
 189   if (before_gc) {
 190     gc_usage_array = _before_gc_usage_array;
 191   } else {
 192     gc_usage_array = _after_gc_usage_array;
 193   }
 194   gc_usage_array[pool_index] = usage;
 195 }
 196 
 197 void GCStatInfo::clear() {
 198   _index = 0;
 199   _start_time = 0L;
 200   _end_time = 0L;
 201   size_t len = _usage_array_size * sizeof(MemoryUsage);
 202   memset(_before_gc_usage_array, 0, len);
 203   memset(_after_gc_usage_array, 0, len);
 204 }
 205 
 206 
 207 GCMemoryManager::GCMemoryManager() : MemoryManager() {
 208   _num_collections = 0;
 209   _last_gc_stat = NULL;
 210   _last_gc_lock = new Mutex(Mutex::leaf, "_last_gc_lock", true);
 211   _current_gc_stat = NULL;
 212   _num_gc_threads = 1;
 213   _notification_enabled = false;
 214 }
 215 
 216 GCMemoryManager::~GCMemoryManager() {
 217   delete _last_gc_stat;
 218   delete _last_gc_lock;
 219   delete _current_gc_stat;
 220 }
 221 
 222 void GCMemoryManager::add_pool(MemoryPool* pool) {
 223   add_pool(pool, true);
 224 }
 225 
 226 void GCMemoryManager::add_pool(MemoryPool* pool, bool always_affected_by_gc) {
 227   int index = MemoryManager::add_pool(pool);
 228   _pool_always_affected_by_gc[index] = always_affected_by_gc;
 229 }
 230 
 231 void GCMemoryManager::initialize_gc_stat_info() {
 232   assert(MemoryService::num_memory_pools() > 0, "should have one or more memory pools");
 233   _last_gc_stat = new(ResourceObj::C_HEAP, mtGC) GCStatInfo(MemoryService::num_memory_pools());
 234   _current_gc_stat = new(ResourceObj::C_HEAP, mtGC) GCStatInfo(MemoryService::num_memory_pools());
 235   // tracking concurrent collections we need two objects: one to update, and one to
 236   // hold the publicly available "last (completed) gc" information.
 237 }
 238 
 239 void GCMemoryManager::gc_begin(bool recordGCBeginTime, bool recordPreGCUsage,
 240                                bool recordAccumulatedGCTime) {
 241   assert(_last_gc_stat != NULL && _current_gc_stat != NULL, "Just checking");
 242   if (recordAccumulatedGCTime) {
 243     _accumulated_timer.start();
 244   }
 245   // _num_collections now increases in gc_end, to count completed collections
 246   if (recordGCBeginTime) {
 247     _current_gc_stat->set_index(_num_collections+1);
 248     _current_gc_stat->set_start_time(Management::timestamp());
 249   }
 250 
 251   if (recordPreGCUsage) {
 252     // Keep memory usage of all memory pools
 253     for (int i = 0; i < MemoryService::num_memory_pools(); i++) {
 254       MemoryPool* pool = MemoryService::get_memory_pool(i);
 255       MemoryUsage usage = pool->get_memory_usage();
 256       _current_gc_stat->set_before_gc_usage(i, usage);
 257 #ifndef USDT2
 258       HS_DTRACE_PROBE8(hotspot, mem__pool__gc__begin,
 259         name(), strlen(name()),
 260         pool->name(), strlen(pool->name()),
 261         usage.init_size(), usage.used(),
 262         usage.committed(), usage.max_size());
 263 #else /* USDT2 */
 264       HOTSPOT_MEM_POOL_GC_BEGIN(
 265         (char *) name(), strlen(name()),
 266         (char *) pool->name(), strlen(pool->name()),
 267         usage.init_size(), usage.used(),
 268         usage.committed(), usage.max_size());
 269 #endif /* USDT2 */
 270     }
 271   }
 272 }
 273 
 274 // A collector MUST, even if it does not complete for some reason,
 275 // make a TraceMemoryManagerStats object where countCollection is true,
 276 // to ensure the current gc stat is placed in _last_gc_stat.
 277 void GCMemoryManager::gc_end(bool recordPostGCUsage,
 278                              bool recordAccumulatedGCTime,
 279                              bool recordGCEndTime, bool countCollection,
 280                              GCCause::Cause cause,
 281                              bool allMemoryPoolsAffected) {
 282   if (recordAccumulatedGCTime) {
 283     _accumulated_timer.stop();
 284   }
 285   if (recordGCEndTime) {
 286     _current_gc_stat->set_end_time(Management::timestamp());
 287   }
 288 
 289   if (recordPostGCUsage) {
 290     int i;
 291     // keep the last gc statistics for all memory pools
 292     for (i = 0; i < MemoryService::num_memory_pools(); i++) {
 293       MemoryPool* pool = MemoryService::get_memory_pool(i);
 294       MemoryUsage usage = pool->get_memory_usage();
 295 
 296 #ifndef USDT2
 297       HS_DTRACE_PROBE8(hotspot, mem__pool__gc__end,
 298         name(), strlen(name()),
 299         pool->name(), strlen(pool->name()),
 300         usage.init_size(), usage.used(),
 301         usage.committed(), usage.max_size());
 302 #else /* USDT2 */
 303       HOTSPOT_MEM_POOL_GC_END(
 304         (char *) name(), strlen(name()),
 305         (char *) pool->name(), strlen(pool->name()),
 306         usage.init_size(), usage.used(),
 307         usage.committed(), usage.max_size());
 308 #endif /* USDT2 */
 309 
 310       _current_gc_stat->set_after_gc_usage(i, usage);
 311     }
 312 
 313     // Set last collection usage of the memory pools managed by this collector
 314     for (i = 0; i < num_memory_pools(); i++) {
 315       MemoryPool* pool = get_memory_pool(i);
 316       MemoryUsage usage = pool->get_memory_usage();
 317 
 318       // Compare with GC usage threshold
 319       if (allMemoryPoolsAffected || pool_always_affected_by_gc(i)) {
 320         // Compare with GC usage threshold
 321         pool->set_last_collection_usage(usage);
 322         LowMemoryDetector::detect_after_gc_memory(pool);
 323       }
 324     }
 325   }
 326 
 327   if (countCollection) {
 328     _num_collections++;
 329     // alternately update two objects making one public when complete
 330     {
 331       MutexLockerEx ml(_last_gc_lock, Mutex::_no_safepoint_check_flag);
 332       GCStatInfo *tmp = _last_gc_stat;
 333       _last_gc_stat = _current_gc_stat;
 334       _current_gc_stat = tmp;
 335       // reset the current stat for diagnosability purposes
 336       _current_gc_stat->clear();
 337     }
 338 
 339     if (is_notification_enabled()) {
 340       bool isMajorGC = this == MemoryService::get_major_gc_manager();
 341       GCNotifier::pushNotification(this, isMajorGC ? "end of major GC" : "end of minor GC",
 342                                    GCCause::to_string(cause));
 343     }
 344   }
 345 }
 346 
 347 size_t GCMemoryManager::get_last_gc_stat(GCStatInfo* dest) {
 348   MutexLockerEx ml(_last_gc_lock, Mutex::_no_safepoint_check_flag);
 349   if (_last_gc_stat->gc_index() != 0) {
 350     dest->set_index(_last_gc_stat->gc_index());
 351     dest->set_start_time(_last_gc_stat->start_time());
 352     dest->set_end_time(_last_gc_stat->end_time());
 353     assert(dest->usage_array_size() == _last_gc_stat->usage_array_size(),
 354            "Must have same array size");
 355     size_t len = dest->usage_array_size() * sizeof(MemoryUsage);
 356     memcpy(dest->before_gc_usage_array(), _last_gc_stat->before_gc_usage_array(), len);
 357     memcpy(dest->after_gc_usage_array(), _last_gc_stat->after_gc_usage_array(), len);
 358   }
 359   return _last_gc_stat->gc_index();
 360 }