1 /*
   2  * Copyright (c) 2003, 2014, 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 void MemoryManager::add_pool(MemoryPool* pool) {
  53   assert(_num_pools < MemoryManager::max_num_pools, "_num_pools exceeds the max");
  54   if (_num_pools < MemoryManager::max_num_pools) {
  55     _pools[_num_pools] = pool;
  56     _num_pools++;
  57   }
  58   pool->add_manager(this);
  59 }
  60 
  61 MemoryManager* MemoryManager::get_code_cache_memory_manager() {
  62   return (MemoryManager*) new CodeCacheMemoryManager();
  63 }
  64 
  65 MemoryManager* MemoryManager::get_metaspace_memory_manager() {
  66   return (MemoryManager*) new MetaspaceMemoryManager();
  67 }
  68 
  69 GCMemoryManager* MemoryManager::get_copy_memory_manager() {
  70   return (GCMemoryManager*) new CopyMemoryManager();
  71 }
  72 
  73 GCMemoryManager* MemoryManager::get_msc_memory_manager() {
  74   return (GCMemoryManager*) new MSCMemoryManager();
  75 }
  76 
  77 GCMemoryManager* MemoryManager::get_parnew_memory_manager() {
  78   return (GCMemoryManager*) new ParNewMemoryManager();
  79 }
  80 
  81 GCMemoryManager* MemoryManager::get_cms_memory_manager() {
  82   return (GCMemoryManager*) new CMSMemoryManager();
  83 }
  84 
  85 GCMemoryManager* MemoryManager::get_psScavenge_memory_manager() {
  86   return (GCMemoryManager*) new PSScavengeMemoryManager();
  87 }
  88 
  89 GCMemoryManager* MemoryManager::get_psMarkSweep_memory_manager() {
  90   return (GCMemoryManager*) new PSMarkSweepMemoryManager();
  91 }
  92 
  93 GCMemoryManager* MemoryManager::get_g1YoungGen_memory_manager() {
  94   return (GCMemoryManager*) new G1YoungGenMemoryManager();
  95 }
  96 
  97 GCMemoryManager* MemoryManager::get_g1OldGen_memory_manager() {
  98   return (GCMemoryManager*) new G1OldGenMemoryManager();
  99 }
 100 
 101 instanceOop MemoryManager::get_memory_manager_instance(TRAPS) {
 102   // Must do an acquire so as to force ordering of subsequent
 103   // loads from anything _memory_mgr_obj points to or implies.
 104   instanceOop mgr_obj = (instanceOop)OrderAccess::load_ptr_acquire(&_memory_mgr_obj);
 105   if (mgr_obj == NULL) {
 106     // It's ok for more than one thread to execute the code up to the locked region.
 107     // Extra manager instances will just be gc'ed.
 108     Klass* k = Management::sun_management_ManagementFactory_klass(CHECK_0);
 109     instanceKlassHandle ik(THREAD, k);
 110 
 111     Handle mgr_name = java_lang_String::create_from_str(name(), CHECK_0);
 112 
 113     JavaValue result(T_OBJECT);
 114     JavaCallArguments args;
 115     args.push_oop(mgr_name);    // Argument 1
 116 
 117     Symbol* method_name = NULL;
 118     Symbol* signature = NULL;
 119     if (is_gc_memory_manager()) {
 120       method_name = vmSymbols::createGarbageCollector_name();
 121       signature = vmSymbols::createGarbageCollector_signature();
 122       args.push_oop(Handle());      // Argument 2 (for future extension)
 123     } else {
 124       method_name = vmSymbols::createMemoryManager_name();
 125       signature = vmSymbols::createMemoryManager_signature();
 126     }
 127 
 128     JavaCalls::call_static(&result,
 129                            ik,
 130                            method_name,
 131                            signature,
 132                            &args,
 133                            CHECK_0);
 134 
 135     instanceOop m = (instanceOop) result.get_jobject();
 136     instanceHandle mgr(THREAD, m);
 137 
 138     {
 139       // Get lock before setting _memory_mgr_obj
 140       // since another thread may have created the instance
 141       MutexLocker ml(Management_lock);
 142 
 143       // Check if another thread has created the management object.  We reload
 144       // _memory_mgr_obj here because some other thread may have initialized
 145       // it while we were executing the code before the lock.
 146       //
 147       // The lock has done an acquire, so the load can't float above it, but
 148       // we need to do a load_acquire as above.
 149       mgr_obj = (instanceOop)OrderAccess::load_ptr_acquire(&_memory_mgr_obj);
 150       if (mgr_obj != NULL) {
 151          return mgr_obj;
 152       }
 153 
 154       // Get the address of the object we created via call_special.
 155       mgr_obj = mgr();
 156 
 157       // Use store barrier to make sure the memory accesses associated
 158       // with creating the management object are visible before publishing
 159       // its address.  The unlock will publish the store to _memory_mgr_obj
 160       // because it does a release first.
 161       OrderAccess::release_store_ptr(&_memory_mgr_obj, mgr_obj);
 162     }
 163   }
 164 
 165   return mgr_obj;
 166 }
 167 
 168 void MemoryManager::oops_do(OopClosure* f) {
 169   f->do_oop((oop*) &_memory_mgr_obj);
 170 }
 171 
 172 GCStatInfo::GCStatInfo(int num_pools) {
 173   // initialize the arrays for memory usage
 174   _before_gc_usage_array = (MemoryUsage*) NEW_C_HEAP_ARRAY(MemoryUsage, num_pools, mtInternal);
 175   _after_gc_usage_array  = (MemoryUsage*) NEW_C_HEAP_ARRAY(MemoryUsage, num_pools, mtInternal);
 176   _usage_array_size = num_pools;
 177   clear();
 178 }
 179 
 180 GCStatInfo::~GCStatInfo() {
 181   FREE_C_HEAP_ARRAY(MemoryUsage*, _before_gc_usage_array, mtInternal);
 182   FREE_C_HEAP_ARRAY(MemoryUsage*, _after_gc_usage_array, mtInternal);
 183 }
 184 
 185 void GCStatInfo::set_gc_usage(int pool_index, MemoryUsage usage, bool before_gc) {
 186   MemoryUsage* gc_usage_array;
 187   if (before_gc) {
 188     gc_usage_array = _before_gc_usage_array;
 189   } else {
 190     gc_usage_array = _after_gc_usage_array;
 191   }
 192   gc_usage_array[pool_index] = usage;
 193 }
 194 
 195 void GCStatInfo::clear() {
 196   _index = 0;
 197   _start_time = 0L;
 198   _end_time = 0L;
 199   size_t len = _usage_array_size * sizeof(MemoryUsage);
 200   memset(_before_gc_usage_array, 0, len);
 201   memset(_after_gc_usage_array, 0, len);
 202 }
 203 
 204 
 205 GCMemoryManager::GCMemoryManager() : MemoryManager() {
 206   _num_collections = 0;
 207   _last_gc_stat = NULL;
 208   _last_gc_lock = new Mutex(Mutex::leaf, "_last_gc_lock", true);
 209   _current_gc_stat = NULL;
 210   _num_gc_threads = 1;
 211   _notification_enabled = false;
 212 }
 213 
 214 GCMemoryManager::~GCMemoryManager() {
 215   delete _last_gc_stat;
 216   delete _last_gc_lock;
 217   delete _current_gc_stat;
 218 }
 219 
 220 void GCMemoryManager::initialize_gc_stat_info() {
 221   assert(MemoryService::num_memory_pools() > 0, "should have one or more memory pools");
 222   _last_gc_stat = new(ResourceObj::C_HEAP, mtGC) GCStatInfo(MemoryService::num_memory_pools());
 223   _current_gc_stat = new(ResourceObj::C_HEAP, mtGC) GCStatInfo(MemoryService::num_memory_pools());
 224   // tracking concurrent collections we need two objects: one to update, and one to
 225   // hold the publicly available "last (completed) gc" information.
 226 }
 227 
 228 void GCMemoryManager::gc_begin(bool recordGCBeginTime, bool recordPreGCUsage,
 229                                bool recordAccumulatedGCTime) {
 230   assert(_last_gc_stat != NULL && _current_gc_stat != NULL, "Just checking");
 231   if (recordAccumulatedGCTime) {
 232     _accumulated_timer.start();
 233   }
 234   // _num_collections now increases in gc_end, to count completed collections
 235   if (recordGCBeginTime) {
 236     _current_gc_stat->set_index(_num_collections+1);
 237     _current_gc_stat->set_start_time(Management::timestamp());
 238   }
 239 
 240   if (recordPreGCUsage) {
 241     // Keep memory usage of all memory pools
 242     for (int i = 0; i < MemoryService::num_memory_pools(); i++) {
 243       MemoryPool* pool = MemoryService::get_memory_pool(i);
 244       MemoryUsage usage = pool->get_memory_usage();
 245       _current_gc_stat->set_before_gc_usage(i, usage);
 246 #ifndef USDT2
 247       HS_DTRACE_PROBE8(hotspot, mem__pool__gc__begin,
 248         name(), strlen(name()),
 249         pool->name(), strlen(pool->name()),
 250         usage.init_size(), usage.used(),
 251         usage.committed(), usage.max_size());
 252 #else /* USDT2 */
 253       HOTSPOT_MEM_POOL_GC_BEGIN(
 254         (char *) name(), strlen(name()),
 255         (char *) pool->name(), strlen(pool->name()),
 256         usage.init_size(), usage.used(),
 257         usage.committed(), usage.max_size());
 258 #endif /* USDT2 */
 259     }
 260   }
 261 }
 262 
 263 // A collector MUST, even if it does not complete for some reason,
 264 // make a TraceMemoryManagerStats object where countCollection is true,
 265 // to ensure the current gc stat is placed in _last_gc_stat.
 266 void GCMemoryManager::gc_end(bool recordPostGCUsage,
 267                              bool recordAccumulatedGCTime,
 268                              bool recordGCEndTime, bool countCollection,
 269                              GCCause::Cause cause) {
 270   if (recordAccumulatedGCTime) {
 271     _accumulated_timer.stop();
 272   }
 273   if (recordGCEndTime) {
 274     _current_gc_stat->set_end_time(Management::timestamp());
 275   }
 276 
 277   if (recordPostGCUsage) {
 278     int i;
 279     // keep the last gc statistics for all memory pools
 280     for (i = 0; i < MemoryService::num_memory_pools(); i++) {
 281       MemoryPool* pool = MemoryService::get_memory_pool(i);
 282       MemoryUsage usage = pool->get_memory_usage();
 283 
 284 #ifndef USDT2
 285       HS_DTRACE_PROBE8(hotspot, mem__pool__gc__end,
 286         name(), strlen(name()),
 287         pool->name(), strlen(pool->name()),
 288         usage.init_size(), usage.used(),
 289         usage.committed(), usage.max_size());
 290 #else /* USDT2 */
 291       HOTSPOT_MEM_POOL_GC_END(
 292         (char *) name(), strlen(name()),
 293         (char *) pool->name(), strlen(pool->name()),
 294         usage.init_size(), usage.used(),
 295         usage.committed(), usage.max_size());
 296 #endif /* USDT2 */
 297 
 298       _current_gc_stat->set_after_gc_usage(i, usage);
 299     }
 300 
 301     // Set last collection usage of the memory pools managed by this collector
 302     for (i = 0; i < num_memory_pools(); i++) {
 303       MemoryPool* pool = get_memory_pool(i);
 304       MemoryUsage usage = pool->get_memory_usage();
 305 
 306       // Compare with GC usage threshold
 307       pool->set_last_collection_usage(usage);
 308       LowMemoryDetector::detect_after_gc_memory(pool);
 309     }
 310   }
 311 
 312   if (countCollection) {
 313     _num_collections++;
 314     // alternately update two objects making one public when complete
 315     {
 316       MutexLockerEx ml(_last_gc_lock, Mutex::_no_safepoint_check_flag);
 317       GCStatInfo *tmp = _last_gc_stat;
 318       _last_gc_stat = _current_gc_stat;
 319       _current_gc_stat = tmp;
 320       // reset the current stat for diagnosability purposes
 321       _current_gc_stat->clear();
 322     }
 323 
 324     if (is_notification_enabled()) {
 325       bool isMajorGC = this == MemoryService::get_major_gc_manager();
 326       GCNotifier::pushNotification(this, isMajorGC ? "end of major GC" : "end of minor GC",
 327                                    GCCause::to_string(cause));
 328     }
 329   }
 330 }
 331 
 332 size_t GCMemoryManager::get_last_gc_stat(GCStatInfo* dest) {
 333   MutexLockerEx ml(_last_gc_lock, Mutex::_no_safepoint_check_flag);
 334   if (_last_gc_stat->gc_index() != 0) {
 335     dest->set_index(_last_gc_stat->gc_index());
 336     dest->set_start_time(_last_gc_stat->start_time());
 337     dest->set_end_time(_last_gc_stat->end_time());
 338     assert(dest->usage_array_size() == _last_gc_stat->usage_array_size(),
 339            "Must have same array size");
 340     size_t len = dest->usage_array_size() * sizeof(MemoryUsage);
 341     memcpy(dest->before_gc_usage_array(), _last_gc_stat->before_gc_usage_array(), len);
 342     memcpy(dest->after_gc_usage_array(), _last_gc_stat->after_gc_usage_array(), len);
 343   }
 344   return _last_gc_stat->gc_index();
 345 }