1 /*
   2  * Copyright (c) 2003, 2012, 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 #ifndef USDT2
  40 HS_DTRACE_PROBE_DECL8(hotspot, mem__pool__gc__begin, char*, int, char*, int,
  41   size_t, size_t, size_t, size_t);
  42 HS_DTRACE_PROBE_DECL8(hotspot, mem__pool__gc__end, char*, int, char*, int,
  43   size_t, size_t, size_t, size_t);
  44 #endif /* !USDT2 */
  45 
  46 MemoryManager::MemoryManager() {
  47   _num_pools = 0;
  48   _memory_mgr_obj = NULL;
  49 }
  50 
  51 void MemoryManager::add_pool(MemoryPool* pool) {
  52   assert(_num_pools < MemoryManager::max_num_pools, "_num_pools exceeds the max");
  53   if (_num_pools < MemoryManager::max_num_pools) {
  54     _pools[_num_pools] = pool;
  55     _num_pools++;
  56   }
  57   pool->add_manager(this);
  58 }
  59 
  60 MemoryManager* MemoryManager::get_code_cache_memory_manager() {
  61   return (MemoryManager*) new CodeCacheMemoryManager();
  62 }
  63 
  64 GCMemoryManager* MemoryManager::get_copy_memory_manager() {
  65   return (GCMemoryManager*) new CopyMemoryManager();
  66 }
  67 
  68 GCMemoryManager* MemoryManager::get_msc_memory_manager() {
  69   return (GCMemoryManager*) new MSCMemoryManager();
  70 }
  71 
  72 GCMemoryManager* MemoryManager::get_parnew_memory_manager() {
  73   return (GCMemoryManager*) new ParNewMemoryManager();
  74 }
  75 
  76 GCMemoryManager* MemoryManager::get_cms_memory_manager() {
  77   return (GCMemoryManager*) new CMSMemoryManager();
  78 }
  79 
  80 GCMemoryManager* MemoryManager::get_psScavenge_memory_manager() {
  81   return (GCMemoryManager*) new PSScavengeMemoryManager();
  82 }
  83 
  84 GCMemoryManager* MemoryManager::get_psMarkSweep_memory_manager() {
  85   return (GCMemoryManager*) new PSMarkSweepMemoryManager();
  86 }
  87 
  88 GCMemoryManager* MemoryManager::get_g1YoungGen_memory_manager() {
  89   return (GCMemoryManager*) new G1YoungGenMemoryManager();
  90 }
  91 
  92 GCMemoryManager* MemoryManager::get_g1OldGen_memory_manager() {
  93   return (GCMemoryManager*) new G1OldGenMemoryManager();
  94 }
  95 
  96 instanceOop MemoryManager::get_memory_manager_instance(TRAPS) {
  97   // Must do an acquire so as to force ordering of subsequent
  98   // loads from anything _memory_mgr_obj points to or implies.
  99   instanceOop mgr_obj = (instanceOop)OrderAccess::load_ptr_acquire(&_memory_mgr_obj);
 100   if (mgr_obj == NULL) {
 101     // It's ok for more than one thread to execute the code up to the locked region.
 102     // Extra manager instances will just be gc'ed.
 103     Klass* k = Management::sun_management_ManagementFactory_klass(CHECK_0);
 104     instanceKlassHandle ik(THREAD, k);
 105 
 106     Handle mgr_name = java_lang_String::create_from_str(name(), CHECK_0);
 107 
 108     JavaValue result(T_OBJECT);
 109     JavaCallArguments args;
 110     args.push_oop(mgr_name);    // Argument 1
 111 
 112     Symbol* method_name = NULL;
 113     Symbol* signature = NULL;
 114     if (is_gc_memory_manager()) {
 115       method_name = vmSymbols::createGarbageCollector_name();
 116       signature = vmSymbols::createGarbageCollector_signature();
 117       args.push_oop(Handle());      // Argument 2 (for future extension)
 118     } else {
 119       method_name = vmSymbols::createMemoryManager_name();
 120       signature = vmSymbols::createMemoryManager_signature();
 121     }
 122 
 123     JavaCalls::call_static(&result,
 124                            ik,
 125                            method_name,
 126                            signature,
 127                            &args,
 128                            CHECK_0);
 129 
 130     instanceOop m = (instanceOop) result.get_jobject();
 131     instanceHandle mgr(THREAD, m);
 132 
 133     {
 134       // Get lock before setting _memory_mgr_obj
 135       // since another thread may have created the instance
 136       MutexLocker ml(Management_lock);
 137 
 138       // Check if another thread has created the management object.  We reload
 139       // _memory_mgr_obj here because some other thread may have initialized
 140       // it while we were executing the code before the lock.
 141       //
 142       // The lock has done an acquire, so the load can't float above it, but
 143       // we need to do a load_acquire as above.
 144       mgr_obj = (instanceOop)OrderAccess::load_ptr_acquire(&_memory_mgr_obj);
 145       if (mgr_obj != NULL) {
 146          return mgr_obj;
 147       }
 148 
 149       // Get the address of the object we created via call_special.
 150       mgr_obj = mgr();
 151 
 152       // Use store barrier to make sure the memory accesses associated
 153       // with creating the management object are visible before publishing
 154       // its address.  The unlock will publish the store to _memory_mgr_obj
 155       // because it does a release first.
 156       OrderAccess::release_store_ptr(&_memory_mgr_obj, mgr_obj);
 157     }
 158   }
 159 
 160   return mgr_obj;
 161 }
 162 
 163 void MemoryManager::oops_do(OopClosure* f) {
 164   f->do_oop((oop*) &_memory_mgr_obj);
 165 }
 166 
 167 GCStatInfo::GCStatInfo(int num_pools) {
 168   // initialize the arrays for memory usage
 169   _before_gc_usage_array = (MemoryUsage*) NEW_C_HEAP_ARRAY(MemoryUsage, num_pools, mtInternal);
 170   _after_gc_usage_array  = (MemoryUsage*) NEW_C_HEAP_ARRAY(MemoryUsage, num_pools, mtInternal);
 171   _usage_array_size = num_pools;
 172   clear();
 173 }
 174 
 175 GCStatInfo::~GCStatInfo() {
 176   FREE_C_HEAP_ARRAY(MemoryUsage*, _before_gc_usage_array, mtInternal);
 177   FREE_C_HEAP_ARRAY(MemoryUsage*, _after_gc_usage_array, mtInternal);
 178 }
 179 
 180 void GCStatInfo::set_gc_usage(int pool_index, MemoryUsage usage, bool before_gc) {
 181   MemoryUsage* gc_usage_array;
 182   if (before_gc) {
 183     gc_usage_array = _before_gc_usage_array;
 184   } else {
 185     gc_usage_array = _after_gc_usage_array;
 186   }
 187   gc_usage_array[pool_index] = usage;
 188 }
 189 
 190 void GCStatInfo::clear() {
 191   _index = 0;
 192   _start_time = 0L;
 193   _end_time = 0L;
 194   size_t len = _usage_array_size * sizeof(MemoryUsage);
 195   memset(_before_gc_usage_array, 0, len);
 196   memset(_after_gc_usage_array, 0, len);
 197 }
 198 
 199 
 200 GCMemoryManager::GCMemoryManager() : MemoryManager() {
 201   _num_collections = 0;
 202   _last_gc_stat = NULL;
 203   _last_gc_lock = new Mutex(Mutex::leaf, "_last_gc_lock", true);
 204   _current_gc_stat = NULL;
 205   _num_gc_threads = 1;
 206   _notification_enabled = false;
 207 }
 208 
 209 GCMemoryManager::~GCMemoryManager() {
 210   delete _last_gc_stat;
 211   delete _last_gc_lock;
 212   delete _current_gc_stat;
 213 }
 214 
 215 void GCMemoryManager::initialize_gc_stat_info() {
 216   assert(MemoryService::num_memory_pools() > 0, "should have one or more memory pools");
 217   _last_gc_stat = new(ResourceObj::C_HEAP, mtGC) GCStatInfo(MemoryService::num_memory_pools());
 218   _current_gc_stat = new(ResourceObj::C_HEAP, mtGC) GCStatInfo(MemoryService::num_memory_pools());
 219   // tracking concurrent collections we need two objects: one to update, and one to
 220   // hold the publicly available "last (completed) gc" information.
 221 }
 222 
 223 void GCMemoryManager::gc_begin(bool recordGCBeginTime, bool recordPreGCUsage,
 224                                bool recordAccumulatedGCTime) {
 225   assert(_last_gc_stat != NULL && _current_gc_stat != NULL, "Just checking");
 226   if (recordAccumulatedGCTime) {
 227     _accumulated_timer.start();
 228   }
 229   // _num_collections now increases in gc_end, to count completed collections
 230   if (recordGCBeginTime) {
 231     _current_gc_stat->set_index(_num_collections+1);
 232     _current_gc_stat->set_start_time(Management::timestamp());
 233   }
 234 
 235   if (recordPreGCUsage) {
 236     // Keep memory usage of all memory pools
 237     for (int i = 0; i < MemoryService::num_memory_pools(); i++) {
 238       MemoryPool* pool = MemoryService::get_memory_pool(i);
 239       MemoryUsage usage = pool->get_memory_usage();
 240       _current_gc_stat->set_before_gc_usage(i, usage);
 241 #ifndef USDT2
 242       HS_DTRACE_PROBE8(hotspot, mem__pool__gc__begin,
 243         name(), strlen(name()),
 244         pool->name(), strlen(pool->name()),
 245         usage.init_size(), usage.used(),
 246         usage.committed(), usage.max_size());
 247 #else /* USDT2 */
 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 #endif /* USDT2 */
 254     }
 255   }
 256 }
 257 
 258 // A collector MUST, even if it does not complete for some reason,
 259 // make a TraceMemoryManagerStats object where countCollection is true,
 260 // to ensure the current gc stat is placed in _last_gc_stat.
 261 void GCMemoryManager::gc_end(bool recordPostGCUsage,
 262                              bool recordAccumulatedGCTime,
 263                              bool recordGCEndTime, bool countCollection,
 264                              GCCause::Cause cause) {
 265   if (recordAccumulatedGCTime) {
 266     _accumulated_timer.stop();
 267   }
 268   if (recordGCEndTime) {
 269     _current_gc_stat->set_end_time(Management::timestamp());
 270   }
 271 
 272   if (recordPostGCUsage) {
 273     int i;
 274     // keep the last gc statistics for all memory pools
 275     for (i = 0; i < MemoryService::num_memory_pools(); i++) {
 276       MemoryPool* pool = MemoryService::get_memory_pool(i);
 277       MemoryUsage usage = pool->get_memory_usage();
 278 
 279 #ifndef USDT2
 280       HS_DTRACE_PROBE8(hotspot, mem__pool__gc__end,
 281         name(), strlen(name()),
 282         pool->name(), strlen(pool->name()),
 283         usage.init_size(), usage.used(),
 284         usage.committed(), usage.max_size());
 285 #else /* USDT2 */
 286       HOTSPOT_MEM_POOL_GC_END(
 287         (char *) name(), strlen(name()),
 288         (char *) pool->name(), strlen(pool->name()),
 289         usage.init_size(), usage.used(),
 290         usage.committed(), usage.max_size());
 291 #endif /* USDT2 */
 292 
 293       _current_gc_stat->set_after_gc_usage(i, usage);
 294     }
 295 
 296     // Set last collection usage of the memory pools managed by this collector
 297     for (i = 0; i < num_memory_pools(); i++) {
 298       MemoryPool* pool = get_memory_pool(i);
 299       MemoryUsage usage = pool->get_memory_usage();
 300 
 301       // Compare with GC usage threshold
 302       pool->set_last_collection_usage(usage);
 303       LowMemoryDetector::detect_after_gc_memory(pool);
 304     }
 305   }
 306 
 307   if (countCollection) {
 308     _num_collections++;
 309     // alternately update two objects making one public when complete
 310     {
 311       MutexLockerEx ml(_last_gc_lock, Mutex::_no_safepoint_check_flag);
 312       GCStatInfo *tmp = _last_gc_stat;
 313       _last_gc_stat = _current_gc_stat;
 314       _current_gc_stat = tmp;
 315       // reset the current stat for diagnosability purposes
 316       _current_gc_stat->clear();
 317     }
 318 
 319     if (is_notification_enabled()) {
 320       bool isMajorGC = this == MemoryService::get_major_gc_manager();
 321       GCNotifier::pushNotification(this, isMajorGC ? "end of major GC" : "end of minor GC",
 322                                    GCCause::to_string(cause));
 323     }
 324   }
 325 }
 326 
 327 size_t GCMemoryManager::get_last_gc_stat(GCStatInfo* dest) {
 328   MutexLockerEx ml(_last_gc_lock, Mutex::_no_safepoint_check_flag);
 329   if (_last_gc_stat->gc_index() != 0) {
 330     dest->set_index(_last_gc_stat->gc_index());
 331     dest->set_start_time(_last_gc_stat->start_time());
 332     dest->set_end_time(_last_gc_stat->end_time());
 333     assert(dest->usage_array_size() == _last_gc_stat->usage_array_size(),
 334            "Must have same array size");
 335     size_t len = dest->usage_array_size() * sizeof(MemoryUsage);
 336     memcpy(dest->before_gc_usage_array(), _last_gc_stat->before_gc_usage_array(), len);
 337     memcpy(dest->after_gc_usage_array(), _last_gc_stat->after_gc_usage_array(), len);
 338   }
 339   return _last_gc_stat->gc_index();
 340 }