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