1 /*
   2  * Copyright (c) 2003, 2017, 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 MemoryManager::MemoryManager() {
  41   _num_pools = 0;
  42   (void)const_cast<instanceOop&>(_memory_mgr_obj = instanceOop(NULL));
  43 }
  44 
  45 void MemoryManager::add_pool(MemoryPool* pool) {
  46   assert(_num_pools < MemoryManager::max_num_pools, "_num_pools exceeds the max");
  47   if (_num_pools < MemoryManager::max_num_pools) {
  48     _pools[_num_pools] = pool;
  49     _num_pools++;
  50   }
  51   pool->add_manager(this);
  52 }
  53 
  54 MemoryManager* MemoryManager::get_code_cache_memory_manager() {
  55   return (MemoryManager*) new CodeCacheMemoryManager();
  56 }
  57 
  58 MemoryManager* MemoryManager::get_metaspace_memory_manager() {
  59   return (MemoryManager*) new MetaspaceMemoryManager();
  60 }
  61 
  62 GCMemoryManager* MemoryManager::get_copy_memory_manager() {
  63   return (GCMemoryManager*) new CopyMemoryManager();
  64 }
  65 
  66 GCMemoryManager* MemoryManager::get_msc_memory_manager() {
  67   return (GCMemoryManager*) new MSCMemoryManager();
  68 }
  69 
  70 GCMemoryManager* MemoryManager::get_parnew_memory_manager() {
  71   return (GCMemoryManager*) new ParNewMemoryManager();
  72 }
  73 
  74 GCMemoryManager* MemoryManager::get_cms_memory_manager() {
  75   return (GCMemoryManager*) new CMSMemoryManager();
  76 }
  77 
  78 GCMemoryManager* MemoryManager::get_psScavenge_memory_manager() {
  79   return (GCMemoryManager*) new PSScavengeMemoryManager();
  80 }
  81 
  82 GCMemoryManager* MemoryManager::get_psMarkSweep_memory_manager() {
  83   return (GCMemoryManager*) new PSMarkSweepMemoryManager();
  84 }
  85 
  86 GCMemoryManager* MemoryManager::get_g1YoungGen_memory_manager() {
  87   return (GCMemoryManager*) new G1YoungGenMemoryManager();
  88 }
  89 
  90 GCMemoryManager* MemoryManager::get_g1OldGen_memory_manager() {
  91   return (GCMemoryManager*) new G1OldGenMemoryManager();
  92 }
  93 
  94 instanceOop MemoryManager::get_memory_manager_instance(TRAPS) {
  95   // Must do an acquire so as to force ordering of subsequent
  96   // loads from anything _memory_mgr_obj points to or implies.
  97   instanceOop mgr_obj = OrderAccess::load_acquire(&_memory_mgr_obj);
  98   if (mgr_obj == NULL) {
  99     // It's ok for more than one thread to execute the code up to the locked region.
 100     // Extra manager instances will just be gc'ed.
 101     Klass* k = Management::sun_management_ManagementFactoryHelper_klass(CHECK_0);
 102 
 103     Handle mgr_name = java_lang_String::create_from_str(name(), CHECK_0);
 104 
 105     JavaValue result(T_OBJECT);
 106     JavaCallArguments args;
 107     args.push_oop(mgr_name);    // Argument 1
 108 
 109     Symbol* method_name = NULL;
 110     Symbol* signature = NULL;
 111     if (is_gc_memory_manager()) {
 112       Klass* extKlass = Management::com_sun_management_internal_GarbageCollectorExtImpl_klass(CHECK_0);
 113       // com.sun.management.GarbageCollectorMXBean is in jdk.management module which may not be present.
 114       if (extKlass != NULL) {
 115         k = extKlass;
 116       }
 117 
 118       method_name = vmSymbols::createGarbageCollector_name();
 119 
 120       signature = vmSymbols::createGarbageCollector_signature();
 121       args.push_oop(Handle());      // Argument 2 (for future extension)
 122     } else {
 123       method_name = vmSymbols::createMemoryManager_name();
 124       signature = vmSymbols::createMemoryManager_signature();
 125     }
 126 
 127     InstanceKlass* ik = InstanceKlass::cast(k);
 128 
 129     JavaCalls::call_static(&result,
 130                            ik,
 131                            method_name,
 132                            signature,
 133                            &args,
 134                            CHECK_0);
 135 
 136     instanceOop m = (instanceOop) result.get_jobject();
 137     instanceHandle mgr(THREAD, m);
 138 
 139     {
 140       // Get lock before setting _memory_mgr_obj
 141       // since another thread may have created the instance
 142       MutexLocker ml(Management_lock);
 143 
 144       // Check if another thread has created the management object.  We reload
 145       // _memory_mgr_obj here because some other thread may have initialized
 146       // it while we were executing the code before the lock.
 147       //
 148       // The lock has done an acquire, so the load can't float above it, but
 149       // we need to do a load_acquire as above.
 150       mgr_obj = OrderAccess::load_acquire(&_memory_mgr_obj);
 151       if (mgr_obj != NULL) {
 152          return mgr_obj;
 153       }
 154 
 155       // Get the address of the object we created via call_special.
 156       mgr_obj = mgr();
 157 
 158       // Use store barrier to make sure the memory accesses associated
 159       // with creating the management object are visible before publishing
 160       // its address.  The unlock will publish the store to _memory_mgr_obj
 161       // because it does a release first.
 162       OrderAccess::release_store(&_memory_mgr_obj, mgr_obj);
 163     }
 164   }
 165 
 166   return mgr_obj;
 167 }
 168 
 169 void MemoryManager::oops_do(OopClosure* f) {
 170   f->do_oop((oop*) &_memory_mgr_obj);
 171 }
 172 
 173 GCStatInfo::GCStatInfo(int num_pools) {
 174   // initialize the arrays for memory usage
 175   _before_gc_usage_array = (MemoryUsage*) NEW_C_HEAP_ARRAY(MemoryUsage, num_pools, mtInternal);
 176   _after_gc_usage_array  = (MemoryUsage*) NEW_C_HEAP_ARRAY(MemoryUsage, num_pools, mtInternal);
 177   _usage_array_size = num_pools;
 178   clear();
 179 }
 180 
 181 GCStatInfo::~GCStatInfo() {
 182   FREE_C_HEAP_ARRAY(MemoryUsage*, _before_gc_usage_array);
 183   FREE_C_HEAP_ARRAY(MemoryUsage*, _after_gc_usage_array);
 184 }
 185 
 186 void GCStatInfo::set_gc_usage(int pool_index, MemoryUsage usage, bool before_gc) {
 187   MemoryUsage* gc_usage_array;
 188   if (before_gc) {
 189     gc_usage_array = _before_gc_usage_array;
 190   } else {
 191     gc_usage_array = _after_gc_usage_array;
 192   }
 193   gc_usage_array[pool_index] = usage;
 194 }
 195 
 196 void GCStatInfo::clear() {
 197   _index = 0;
 198   _start_time = 0L;
 199   _end_time = 0L;
 200   size_t len = _usage_array_size * sizeof(MemoryUsage);
 201   memset(_before_gc_usage_array, 0, len);
 202   memset(_after_gc_usage_array, 0, len);
 203 }
 204 
 205 
 206 GCMemoryManager::GCMemoryManager() : MemoryManager() {
 207   _num_collections = 0;
 208   _last_gc_stat = NULL;
 209   _last_gc_lock = new Mutex(Mutex::leaf, "_last_gc_lock", true,
 210                             Monitor::_safepoint_check_never);
 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::initialize_gc_stat_info() {
 223   assert(MemoryService::num_memory_pools() > 0, "should have one or more memory pools");
 224   _last_gc_stat = new(ResourceObj::C_HEAP, mtGC) GCStatInfo(MemoryService::num_memory_pools());
 225   _current_gc_stat = new(ResourceObj::C_HEAP, mtGC) GCStatInfo(MemoryService::num_memory_pools());
 226   // tracking concurrent collections we need two objects: one to update, and one to
 227   // hold the publicly available "last (completed) gc" information.
 228 }
 229 
 230 void GCMemoryManager::gc_begin(bool recordGCBeginTime, bool recordPreGCUsage,
 231                                bool recordAccumulatedGCTime) {
 232   assert(_last_gc_stat != NULL && _current_gc_stat != NULL, "Just checking");
 233   if (recordAccumulatedGCTime) {
 234     _accumulated_timer.start();
 235   }
 236   // _num_collections now increases in gc_end, to count completed collections
 237   if (recordGCBeginTime) {
 238     _current_gc_stat->set_index(_num_collections+1);
 239     _current_gc_stat->set_start_time(Management::timestamp());
 240   }
 241 
 242   if (recordPreGCUsage) {
 243     // Keep memory usage of all memory pools
 244     for (int i = 0; i < MemoryService::num_memory_pools(); i++) {
 245       MemoryPool* pool = MemoryService::get_memory_pool(i);
 246       MemoryUsage usage = pool->get_memory_usage();
 247       _current_gc_stat->set_before_gc_usage(i, usage);
 248       HOTSPOT_MEM_POOL_GC_BEGIN(
 249         (char *) name(), strlen(name()),
 250         (char *) pool->name(), strlen(pool->name()),
 251         usage.init_size(), usage.used(),
 252         usage.committed(), usage.max_size());
 253     }
 254   }
 255 }
 256 
 257 // A collector MUST, even if it does not complete for some reason,
 258 // make a TraceMemoryManagerStats object where countCollection is true,
 259 // to ensure the current gc stat is placed in _last_gc_stat.
 260 void GCMemoryManager::gc_end(bool recordPostGCUsage,
 261                              bool recordAccumulatedGCTime,
 262                              bool recordGCEndTime, bool countCollection,
 263                              GCCause::Cause cause) {
 264   if (recordAccumulatedGCTime) {
 265     _accumulated_timer.stop();
 266   }
 267   if (recordGCEndTime) {
 268     _current_gc_stat->set_end_time(Management::timestamp());
 269   }
 270 
 271   if (recordPostGCUsage) {
 272     int i;
 273     // keep the last gc statistics for all memory pools
 274     for (i = 0; i < MemoryService::num_memory_pools(); i++) {
 275       MemoryPool* pool = MemoryService::get_memory_pool(i);
 276       MemoryUsage usage = pool->get_memory_usage();
 277 
 278       HOTSPOT_MEM_POOL_GC_END(
 279         (char *) name(), strlen(name()),
 280         (char *) pool->name(), strlen(pool->name()),
 281         usage.init_size(), usage.used(),
 282         usage.committed(), usage.max_size());
 283 
 284       _current_gc_stat->set_after_gc_usage(i, usage);
 285     }
 286 
 287     // Set last collection usage of the memory pools managed by this collector
 288     for (i = 0; i < num_memory_pools(); i++) {
 289       MemoryPool* pool = get_memory_pool(i);
 290       MemoryUsage usage = pool->get_memory_usage();
 291 
 292       // Compare with GC usage threshold
 293       pool->set_last_collection_usage(usage);
 294       LowMemoryDetector::detect_after_gc_memory(pool);
 295     }
 296   }
 297 
 298   if (countCollection) {
 299     _num_collections++;
 300     // alternately update two objects making one public when complete
 301     {
 302       MutexLockerEx ml(_last_gc_lock, Mutex::_no_safepoint_check_flag);
 303       GCStatInfo *tmp = _last_gc_stat;
 304       _last_gc_stat = _current_gc_stat;
 305       _current_gc_stat = tmp;
 306       // reset the current stat for diagnosability purposes
 307       _current_gc_stat->clear();
 308     }
 309 
 310     if (is_notification_enabled()) {
 311       bool isMajorGC = this == MemoryService::get_major_gc_manager();
 312       GCNotifier::pushNotification(this, isMajorGC ? "end of major GC" : "end of minor GC",
 313                                    GCCause::to_string(cause));
 314     }
 315   }
 316 }
 317 
 318 size_t GCMemoryManager::get_last_gc_stat(GCStatInfo* dest) {
 319   MutexLockerEx ml(_last_gc_lock, Mutex::_no_safepoint_check_flag);
 320   if (_last_gc_stat->gc_index() != 0) {
 321     dest->set_index(_last_gc_stat->gc_index());
 322     dest->set_start_time(_last_gc_stat->start_time());
 323     dest->set_end_time(_last_gc_stat->end_time());
 324     assert(dest->usage_array_size() == _last_gc_stat->usage_array_size(),
 325            "Must have same array size");
 326     size_t len = dest->usage_array_size() * sizeof(MemoryUsage);
 327     memcpy(dest->before_gc_usage_array(), _last_gc_stat->before_gc_usage_array(), len);
 328     memcpy(dest->after_gc_usage_array(), _last_gc_stat->after_gc_usage_array(), len);
 329   }
 330   return _last_gc_stat->gc_index();
 331 }