1 /*
   2  * Copyright (c) 2003, 2013, 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 "services/lowMemoryDetector.hpp"
  32 #include "services/management.hpp"
  33 #include "services/memoryManager.hpp"
  34 #include "services/memoryPool.hpp"
  35 #include "services/memoryService.hpp"
  36 #include "services/gcNotifier.hpp"
  37 #include "utilities/dtrace.hpp"
  38 
  39 MemoryManager::MemoryManager() {
  40   _num_pools = 0;
  41   (void)const_cast<instanceOop&>(_memory_mgr_obj = NULL);
  42 }
  43 
  44 void MemoryManager::add_pool(MemoryPool* pool) {
  45   assert(_num_pools < MemoryManager::max_num_pools, "_num_pools exceeds the max");
  46   if (_num_pools < MemoryManager::max_num_pools) {
  47     _pools[_num_pools] = pool;
  48     _num_pools++;
  49   }
  50   pool->add_manager(this);
  51 }
  52 
  53 MemoryManager* MemoryManager::get_code_cache_memory_manager() {
  54   return (MemoryManager*) new CodeCacheMemoryManager();
  55 }
  56 
  57 MemoryManager* MemoryManager::get_metaspace_memory_manager() {
  58   return (MemoryManager*) new MetaspaceMemoryManager();
  59 }
  60 
  61 GCMemoryManager* MemoryManager::get_copy_memory_manager() {
  62   return (GCMemoryManager*) new CopyMemoryManager();
  63 }
  64 
  65 GCMemoryManager* MemoryManager::get_msc_memory_manager() {
  66   return (GCMemoryManager*) new MSCMemoryManager();
  67 }
  68 
  69 GCMemoryManager* MemoryManager::get_parnew_memory_manager() {
  70   return (GCMemoryManager*) new ParNewMemoryManager();
  71 }
  72 
  73 GCMemoryManager* MemoryManager::get_cms_memory_manager() {
  74   return (GCMemoryManager*) new CMSMemoryManager();
  75 }
  76 
  77 GCMemoryManager* MemoryManager::get_psScavenge_memory_manager() {
  78   return (GCMemoryManager*) new PSScavengeMemoryManager();
  79 }
  80 
  81 GCMemoryManager* MemoryManager::get_psMarkSweep_memory_manager() {
  82   return (GCMemoryManager*) new PSMarkSweepMemoryManager();
  83 }
  84 
  85 GCMemoryManager* MemoryManager::get_g1YoungGen_memory_manager() {
  86   return (GCMemoryManager*) new G1YoungGenMemoryManager();
  87 }
  88 
  89 GCMemoryManager* MemoryManager::get_g1OldGen_memory_manager() {
  90   return (GCMemoryManager*) new G1OldGenMemoryManager();
  91 }
  92 
  93 instanceOop MemoryManager::get_memory_manager_instance(TRAPS) {
  94   // Must do an acquire so as to force ordering of subsequent
  95   // loads from anything _memory_mgr_obj points to or implies.
  96   instanceOop mgr_obj = (instanceOop)OrderAccess::load_ptr_acquire(&_memory_mgr_obj);
  97   if (mgr_obj == NULL) {
  98     // It's ok for more than one thread to execute the code up to the locked region.
  99     // Extra manager instances will just be gc'ed.
 100     Klass* k = Management::sun_management_ManagementFactory_klass(CHECK_0);
 101     instanceKlassHandle ik(THREAD, k);
 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       method_name = vmSymbols::createGarbageCollector_name();
 113       signature = vmSymbols::createGarbageCollector_signature();
 114       args.push_oop(Handle());      // Argument 2 (for future extension)
 115     } else {
 116       method_name = vmSymbols::createMemoryManager_name();
 117       signature = vmSymbols::createMemoryManager_signature();
 118     }
 119 
 120     JavaCalls::call_static(&result,
 121                            ik,
 122                            method_name,
 123                            signature,
 124                            &args,
 125                            CHECK_0);
 126 
 127     instanceOop m = (instanceOop) result.get_jobject();
 128     instanceHandle mgr(THREAD, m);
 129 
 130     {
 131       // Get lock before setting _memory_mgr_obj
 132       // since another thread may have created the instance
 133       MutexLocker ml(Management_lock);
 134 
 135       // Check if another thread has created the management object.  We reload
 136       // _memory_mgr_obj here because some other thread may have initialized
 137       // it while we were executing the code before the lock.
 138       //
 139       // The lock has done an acquire, so the load can't float above it, but
 140       // we need to do a load_acquire as above.
 141       mgr_obj = (instanceOop)OrderAccess::load_ptr_acquire(&_memory_mgr_obj);
 142       if (mgr_obj != NULL) {
 143          return mgr_obj;
 144       }
 145 
 146       // Get the address of the object we created via call_special.
 147       mgr_obj = mgr();
 148 
 149       // Use store barrier to make sure the memory accesses associated
 150       // with creating the management object are visible before publishing
 151       // its address.  The unlock will publish the store to _memory_mgr_obj
 152       // because it does a release first.
 153       OrderAccess::release_store_ptr(&_memory_mgr_obj, mgr_obj);
 154     }
 155   }
 156 
 157   return mgr_obj;
 158 }
 159 
 160 void MemoryManager::oops_do(OopClosure* f) {
 161   f->do_oop((oop*) &_memory_mgr_obj);
 162 }
 163 
 164 GCStatInfo::GCStatInfo(int num_pools) {
 165   // initialize the arrays for memory usage
 166   _before_gc_usage_array = (MemoryUsage*) NEW_C_HEAP_ARRAY(MemoryUsage, num_pools, mtInternal);
 167   _after_gc_usage_array  = (MemoryUsage*) NEW_C_HEAP_ARRAY(MemoryUsage, num_pools, mtInternal);
 168   _usage_array_size = num_pools;
 169   clear();
 170 }
 171 
 172 GCStatInfo::~GCStatInfo() {
 173   FREE_C_HEAP_ARRAY(MemoryUsage*, _before_gc_usage_array, mtInternal);
 174   FREE_C_HEAP_ARRAY(MemoryUsage*, _after_gc_usage_array, mtInternal);
 175 }
 176 
 177 void GCStatInfo::set_gc_usage(int pool_index, MemoryUsage usage, bool before_gc) {
 178   MemoryUsage* gc_usage_array;
 179   if (before_gc) {
 180     gc_usage_array = _before_gc_usage_array;
 181   } else {
 182     gc_usage_array = _after_gc_usage_array;
 183   }
 184   gc_usage_array[pool_index] = usage;
 185 }
 186 
 187 void GCStatInfo::clear() {
 188   _index = 0;
 189   _start_time = 0L;
 190   _end_time = 0L;
 191   size_t len = _usage_array_size * sizeof(MemoryUsage);
 192   memset(_before_gc_usage_array, 0, len);
 193   memset(_after_gc_usage_array, 0, len);
 194 }
 195 
 196 
 197 GCMemoryManager::GCMemoryManager() : MemoryManager() {
 198   _num_collections = 0;
 199   _last_gc_stat = NULL;
 200   _last_gc_lock = new Mutex(Mutex::leaf, "_last_gc_lock", true);
 201   _current_gc_stat = NULL;
 202   _num_gc_threads = 1;
 203   _notification_enabled = false;
 204 }
 205 
 206 GCMemoryManager::~GCMemoryManager() {
 207   delete _last_gc_stat;
 208   delete _last_gc_lock;
 209   delete _current_gc_stat;
 210 }
 211 
 212 void GCMemoryManager::initialize_gc_stat_info() {
 213   assert(MemoryService::num_memory_pools() > 0, "should have one or more memory pools");
 214   _last_gc_stat = new(ResourceObj::C_HEAP, mtGC) GCStatInfo(MemoryService::num_memory_pools());
 215   _current_gc_stat = new(ResourceObj::C_HEAP, mtGC) GCStatInfo(MemoryService::num_memory_pools());
 216   // tracking concurrent collections we need two objects: one to update, and one to
 217   // hold the publicly available "last (completed) gc" information.
 218 }
 219 
 220 void GCMemoryManager::gc_begin(bool recordGCBeginTime, bool recordPreGCUsage,
 221                                bool recordAccumulatedGCTime) {
 222   assert(_last_gc_stat != NULL && _current_gc_stat != NULL, "Just checking");
 223   if (recordAccumulatedGCTime) {
 224     _accumulated_timer.start();
 225   }
 226   // _num_collections now increases in gc_end, to count completed collections
 227   if (recordGCBeginTime) {
 228     _current_gc_stat->set_index(_num_collections+1);
 229     _current_gc_stat->set_start_time(Management::timestamp());
 230   }
 231 
 232   if (recordPreGCUsage) {
 233     // Keep memory usage of all memory pools
 234     for (int i = 0; i < MemoryService::num_memory_pools(); i++) {
 235       MemoryPool* pool = MemoryService::get_memory_pool(i);
 236       MemoryUsage usage = pool->get_memory_usage();
 237       _current_gc_stat->set_before_gc_usage(i, usage);
 238       HOTSPOT_MEM_POOL_GC_BEGIN(
 239         (char *) name(), strlen(name()),
 240         (char *) pool->name(), strlen(pool->name()),
 241         usage.init_size(), usage.used(),
 242         usage.committed(), usage.max_size());
 243     }
 244   }
 245 }
 246 
 247 // A collector MUST, even if it does not complete for some reason,
 248 // make a TraceMemoryManagerStats object where countCollection is true,
 249 // to ensure the current gc stat is placed in _last_gc_stat.
 250 void GCMemoryManager::gc_end(bool recordPostGCUsage,
 251                              bool recordAccumulatedGCTime,
 252                              bool recordGCEndTime, bool countCollection,
 253                              GCCause::Cause cause) {
 254   if (recordAccumulatedGCTime) {
 255     _accumulated_timer.stop();
 256   }
 257   if (recordGCEndTime) {
 258     _current_gc_stat->set_end_time(Management::timestamp());
 259   }
 260 
 261   if (recordPostGCUsage) {
 262     int i;
 263     // keep the last gc statistics for all memory pools
 264     for (i = 0; i < MemoryService::num_memory_pools(); i++) {
 265       MemoryPool* pool = MemoryService::get_memory_pool(i);
 266       MemoryUsage usage = pool->get_memory_usage();
 267 
 268       HOTSPOT_MEM_POOL_GC_END(
 269         (char *) name(), strlen(name()),
 270         (char *) pool->name(), strlen(pool->name()),
 271         usage.init_size(), usage.used(),
 272         usage.committed(), usage.max_size());
 273 
 274       _current_gc_stat->set_after_gc_usage(i, usage);
 275     }
 276 
 277     // Set last collection usage of the memory pools managed by this collector
 278     for (i = 0; i < num_memory_pools(); i++) {
 279       MemoryPool* pool = get_memory_pool(i);
 280       MemoryUsage usage = pool->get_memory_usage();
 281 
 282       // Compare with GC usage threshold
 283       pool->set_last_collection_usage(usage);
 284       LowMemoryDetector::detect_after_gc_memory(pool);
 285     }
 286   }
 287 
 288   if (countCollection) {
 289     _num_collections++;
 290     // alternately update two objects making one public when complete
 291     {
 292       MutexLockerEx ml(_last_gc_lock, Mutex::_no_safepoint_check_flag);
 293       GCStatInfo *tmp = _last_gc_stat;
 294       _last_gc_stat = _current_gc_stat;
 295       _current_gc_stat = tmp;
 296       // reset the current stat for diagnosability purposes
 297       _current_gc_stat->clear();
 298     }
 299 
 300     if (is_notification_enabled()) {
 301       bool isMajorGC = this == MemoryService::get_major_gc_manager();
 302       GCNotifier::pushNotification(this, isMajorGC ? "end of major GC" : "end of minor GC",
 303                                    GCCause::to_string(cause));
 304     }
 305   }
 306 }
 307 
 308 size_t GCMemoryManager::get_last_gc_stat(GCStatInfo* dest) {
 309   MutexLockerEx ml(_last_gc_lock, Mutex::_no_safepoint_check_flag);
 310   if (_last_gc_stat->gc_index() != 0) {
 311     dest->set_index(_last_gc_stat->gc_index());
 312     dest->set_start_time(_last_gc_stat->start_time());
 313     dest->set_end_time(_last_gc_stat->end_time());
 314     assert(dest->usage_array_size() == _last_gc_stat->usage_array_size(),
 315            "Must have same array size");
 316     size_t len = dest->usage_array_size() * sizeof(MemoryUsage);
 317     memcpy(dest->before_gc_usage_array(), _last_gc_stat->before_gc_usage_array(), len);
 318     memcpy(dest->after_gc_usage_array(), _last_gc_stat->after_gc_usage_array(), len);
 319   }
 320   return _last_gc_stat->gc_index();
 321 }