1 /*
2 * Copyright (c) 2003, 2018, 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 void MemoryManager::add_pool(MemoryPool* pool) {
47 assert(_num_pools < MemoryManager::max_num_pools, "_num_pools exceeds the max");
48 if (_num_pools < MemoryManager::max_num_pools) {
49 _pools[_num_pools] = pool;
50 _num_pools++;
51 }
52 pool->add_manager(this);
53 }
54
55 MemoryManager* MemoryManager::get_code_cache_memory_manager() {
56 return new MemoryManager("CodeCacheManager");
57 }
58
59 MemoryManager* MemoryManager::get_metaspace_memory_manager() {
60 return new MemoryManager("Metaspace Manager");
61 }
62
63 instanceOop MemoryManager::get_memory_manager_instance(TRAPS) {
64 // Must do an acquire so as to force ordering of subsequent
65 // loads from anything _memory_mgr_obj points to or implies.
66 instanceOop mgr_obj = OrderAccess::load_acquire(&_memory_mgr_obj);
67 if (mgr_obj == NULL) {
68 // It's ok for more than one thread to execute the code up to the locked region.
69 // Extra manager instances will just be gc'ed.
70 Klass* k = Management::sun_management_ManagementFactoryHelper_klass(CHECK_0);
71
72 Handle mgr_name = java_lang_String::create_from_str(name(), CHECK_0);
73
74 JavaValue result(T_OBJECT);
75 JavaCallArguments args;
76 args.push_oop(mgr_name); // Argument 1
77
78 Symbol* method_name = NULL;
79 Symbol* signature = NULL;
80 if (is_gc_memory_manager()) {
81 Klass* extKlass = Management::com_sun_management_internal_GarbageCollectorExtImpl_klass(CHECK_0);
82 // com.sun.management.GarbageCollectorMXBean is in jdk.management module which may not be present.
83 if (extKlass != NULL) {
84 k = extKlass;
85 }
86
87 method_name = vmSymbols::createGarbageCollector_name();
88
89 signature = vmSymbols::createGarbageCollector_signature();
90 args.push_oop(Handle()); // Argument 2 (for future extension)
91 } else {
92 method_name = vmSymbols::createMemoryManager_name();
93 signature = vmSymbols::createMemoryManager_signature();
94 }
95
96 InstanceKlass* ik = InstanceKlass::cast(k);
97
98 JavaCalls::call_static(&result,
99 ik,
100 method_name,
101 signature,
102 &args,
103 CHECK_0);
104
105 instanceOop m = (instanceOop) result.get_jobject();
106 instanceHandle mgr(THREAD, m);
107
108 {
109 // Get lock before setting _memory_mgr_obj
110 // since another thread may have created the instance
111 MutexLocker ml(Management_lock);
112
113 // Check if another thread has created the management object. We reload
114 // _memory_mgr_obj here because some other thread may have initialized
115 // it while we were executing the code before the lock.
116 //
117 // The lock has done an acquire, so the load can't float above it, but
118 // we need to do a load_acquire as above.
119 mgr_obj = OrderAccess::load_acquire(&_memory_mgr_obj);
120 if (mgr_obj != NULL) {
121 return mgr_obj;
122 }
123
124 // Get the address of the object we created via call_special.
125 mgr_obj = mgr();
126
127 // Use store barrier to make sure the memory accesses associated
128 // with creating the management object are visible before publishing
129 // its address. The unlock will publish the store to _memory_mgr_obj
130 // because it does a release first.
131 OrderAccess::release_store(&_memory_mgr_obj, mgr_obj);
132 }
133 }
134
135 return mgr_obj;
136 }
137
138 void MemoryManager::oops_do(OopClosure* f) {
139 f->do_oop((oop*) &_memory_mgr_obj);
140 }
141
142 GCStatInfo::GCStatInfo(int num_pools) {
143 // initialize the arrays for memory usage
144 _before_gc_usage_array = (MemoryUsage*) NEW_C_HEAP_ARRAY(MemoryUsage, num_pools, mtInternal);
145 _after_gc_usage_array = (MemoryUsage*) NEW_C_HEAP_ARRAY(MemoryUsage, num_pools, mtInternal);
146 _usage_array_size = num_pools;
147 clear();
148 }
149
150 GCStatInfo::~GCStatInfo() {
151 FREE_C_HEAP_ARRAY(MemoryUsage*, _before_gc_usage_array);
152 FREE_C_HEAP_ARRAY(MemoryUsage*, _after_gc_usage_array);
153 }
154
155 void GCStatInfo::set_gc_usage(int pool_index, MemoryUsage usage, bool before_gc) {
156 MemoryUsage* gc_usage_array;
157 if (before_gc) {
158 gc_usage_array = _before_gc_usage_array;
159 } else {
160 gc_usage_array = _after_gc_usage_array;
161 }
162 gc_usage_array[pool_index] = usage;
163 }
164
165 void GCStatInfo::clear() {
166 _index = 0;
167 _start_time = 0L;
168 _end_time = 0L;
169 size_t len = _usage_array_size * sizeof(MemoryUsage);
170 memset(_before_gc_usage_array, 0, len);
171 memset(_after_gc_usage_array, 0, len);
172 }
173
174
175 GCMemoryManager::GCMemoryManager(const char* name, const char* gc_end_message) :
176 MemoryManager(name), _gc_end_message(gc_end_message) {
177 _num_collections = 0;
178 _last_gc_stat = NULL;
179 _last_gc_lock = new Mutex(Mutex::leaf, "_last_gc_lock", true,
180 Monitor::_safepoint_check_never);
181 _current_gc_stat = NULL;
182 _num_gc_threads = 1;
183 _notification_enabled = false;
184 }
185
186 GCMemoryManager::~GCMemoryManager() {
187 delete _last_gc_stat;
188 delete _last_gc_lock;
189 delete _current_gc_stat;
190 }
191
192 void GCMemoryManager::initialize_gc_stat_info() {
193 assert(MemoryService::num_memory_pools() > 0, "should have one or more memory pools");
194 _last_gc_stat = new(ResourceObj::C_HEAP, mtGC) GCStatInfo(MemoryService::num_memory_pools());
195 _current_gc_stat = new(ResourceObj::C_HEAP, mtGC) GCStatInfo(MemoryService::num_memory_pools());
196 // tracking concurrent collections we need two objects: one to update, and one to
197 // hold the publicly available "last (completed) gc" information.
198 }
199
200 void GCMemoryManager::gc_begin(bool recordGCBeginTime, bool recordPreGCUsage,
201 bool recordAccumulatedGCTime) {
202 assert(_last_gc_stat != NULL && _current_gc_stat != NULL, "Just checking");
203 if (recordAccumulatedGCTime) {
204 _accumulated_timer.start();
205 }
206 // _num_collections now increases in gc_end, to count completed collections
207 if (recordGCBeginTime) {
208 _current_gc_stat->set_index(_num_collections+1);
209 _current_gc_stat->set_start_time(Management::timestamp());
210 }
211
212 if (recordPreGCUsage) {
213 // Keep memory usage of all memory pools
214 for (int i = 0; i < MemoryService::num_memory_pools(); i++) {
215 MemoryPool* pool = MemoryService::get_memory_pool(i);
216 MemoryUsage usage = pool->get_memory_usage();
217 _current_gc_stat->set_before_gc_usage(i, usage);
218 HOTSPOT_MEM_POOL_GC_BEGIN(
219 (char *) name(), strlen(name()),
220 (char *) pool->name(), strlen(pool->name()),
221 usage.init_size(), usage.used(),
222 usage.committed(), usage.max_size());
223 }
224 }
225 }
226
227 // A collector MUST, even if it does not complete for some reason,
228 // make a TraceMemoryManagerStats object where countCollection is true,
229 // to ensure the current gc stat is placed in _last_gc_stat.
230 void GCMemoryManager::gc_end(bool recordPostGCUsage,
231 bool recordAccumulatedGCTime,
232 bool recordGCEndTime, bool countCollection,
233 GCCause::Cause cause) {
234 if (recordAccumulatedGCTime) {
235 _accumulated_timer.stop();
236 }
237 if (recordGCEndTime) {
238 _current_gc_stat->set_end_time(Management::timestamp());
239 }
240
241 if (recordPostGCUsage) {
242 int i;
243 // keep the last gc statistics for all memory pools
244 for (i = 0; i < MemoryService::num_memory_pools(); i++) {
245 MemoryPool* pool = MemoryService::get_memory_pool(i);
246 MemoryUsage usage = pool->get_memory_usage();
247
248 HOTSPOT_MEM_POOL_GC_END(
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 _current_gc_stat->set_after_gc_usage(i, usage);
255 }
256
257 // Set last collection usage of the memory pools managed by this collector
258 for (i = 0; i < num_memory_pools(); i++) {
259 MemoryPool* pool = get_memory_pool(i);
260 MemoryUsage usage = pool->get_memory_usage();
261
262 // Compare with GC usage threshold
263 pool->set_last_collection_usage(usage);
264 LowMemoryDetector::detect_after_gc_memory(pool);
265 }
266 }
267
268 if (countCollection) {
269 _num_collections++;
270 // alternately update two objects making one public when complete
271 {
272 MutexLockerEx ml(_last_gc_lock, Mutex::_no_safepoint_check_flag);
273 GCStatInfo *tmp = _last_gc_stat;
274 _last_gc_stat = _current_gc_stat;
275 _current_gc_stat = tmp;
276 // reset the current stat for diagnosability purposes
277 _current_gc_stat->clear();
278 }
279
280 if (is_notification_enabled()) {
281 GCNotifier::pushNotification(this, _gc_end_message, GCCause::to_string(cause));
282 }
283 }
284 }
285
286 size_t GCMemoryManager::get_last_gc_stat(GCStatInfo* dest) {
287 MutexLockerEx ml(_last_gc_lock, Mutex::_no_safepoint_check_flag);
288 if (_last_gc_stat->gc_index() != 0) {
289 dest->set_index(_last_gc_stat->gc_index());
290 dest->set_start_time(_last_gc_stat->start_time());
291 dest->set_end_time(_last_gc_stat->end_time());
292 assert(dest->usage_array_size() == _last_gc_stat->usage_array_size(),
293 "Must have same array size");
294 size_t len = dest->usage_array_size() * sizeof(MemoryUsage);
295 memcpy(dest->before_gc_usage_array(), _last_gc_stat->before_gc_usage_array(), len);
296 memcpy(dest->after_gc_usage_array(), _last_gc_stat->after_gc_usage_array(), len);
297 }
298 return _last_gc_stat->gc_index();
299 }