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 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 size_t len = _usage_array_size * sizeof(MemoryUsage);
172 memset(_before_gc_usage_array, 0, len);
173 memset(_after_gc_usage_array, 0, len);
174 }
175
176
177 GCMemoryManager::GCMemoryManager(const char* name, const char* gc_end_message) :
178 MemoryManager(name), _gc_end_message(gc_end_message) {
179 _num_collections = 0;
180 _last_gc_stat = NULL;
181 _last_gc_lock = new Mutex(Mutex::leaf, "_last_gc_lock", true,
182 Monitor::_safepoint_check_never);
183 _current_gc_stat = NULL;
184 _num_gc_threads = 1;
185 _notification_enabled = false;
186 }
187
188 GCMemoryManager::~GCMemoryManager() {
189 delete _last_gc_stat;
190 delete _last_gc_lock;
191 delete _current_gc_stat;
192 }
193
194 void GCMemoryManager::add_pool(MemoryPool* pool) {
195 add_pool(pool, true);
196 }
197
198 void GCMemoryManager::add_pool(MemoryPool* pool, bool always_affected_by_gc) {
199 int index = MemoryManager::add_pool(pool);
200 _pool_always_affected_by_gc[index] = always_affected_by_gc;
201 }
202
203 void GCMemoryManager::initialize_gc_stat_info() {
204 assert(MemoryService::num_memory_pools() > 0, "should have one or more memory pools");
205 _last_gc_stat = new(ResourceObj::C_HEAP, mtGC) GCStatInfo(MemoryService::num_memory_pools());
206 _current_gc_stat = new(ResourceObj::C_HEAP, mtGC) GCStatInfo(MemoryService::num_memory_pools());
207 // tracking concurrent collections we need two objects: one to update, and one to
208 // hold the publicly available "last (completed) gc" information.
209 }
210
211 void GCMemoryManager::gc_begin(bool recordGCBeginTime, bool recordPreGCUsage,
212 bool recordAccumulatedGCTime) {
213 // Inactive memory managers (concurrent in G1 legacy mode) will not be initialized.
214 if (_last_gc_stat == NULL && _current_gc_stat == NULL) return;
215
216 if (recordAccumulatedGCTime) {
217 _accumulated_timer.start();
218 }
219 // _num_collections now increases in gc_end, to count completed collections
220 if (recordGCBeginTime) {
221 _current_gc_stat->set_index(_num_collections+1);
222 _current_gc_stat->set_start_time(Management::timestamp());
223 }
224
225 if (recordPreGCUsage) {
226 // Keep memory usage of all memory pools
227 for (int i = 0; i < MemoryService::num_memory_pools(); i++) {
228 MemoryPool* pool = MemoryService::get_memory_pool(i);
229 MemoryUsage usage = pool->get_memory_usage();
230 _current_gc_stat->set_before_gc_usage(i, usage);
231 HOTSPOT_MEM_POOL_GC_BEGIN(
232 (char *) name(), strlen(name()),
233 (char *) pool->name(), strlen(pool->name()),
234 usage.init_size(), usage.used(),
235 usage.committed(), usage.max_size());
236 }
237 }
238 }
239
240 // A collector MUST, even if it does not complete for some reason,
241 // make a TraceMemoryManagerStats object where countCollection is true,
242 // to ensure the current gc stat is placed in _last_gc_stat.
243 void GCMemoryManager::gc_end(bool recordPostGCUsage,
244 bool recordAccumulatedGCTime,
245 bool recordGCEndTime, bool countCollection,
246 GCCause::Cause cause,
247 bool allMemoryPoolsAffected) {
248 if (_last_gc_stat == NULL && _current_gc_stat == NULL) return;
249
250 if (recordAccumulatedGCTime) {
251 _accumulated_timer.stop();
252 }
253 if (recordGCEndTime) {
254 _current_gc_stat->set_end_time(Management::timestamp());
255 }
256
257 if (recordPostGCUsage) {
258 int i;
259 // keep the last gc statistics for all memory pools
260 for (i = 0; i < MemoryService::num_memory_pools(); i++) {
261 MemoryPool* pool = MemoryService::get_memory_pool(i);
262 MemoryUsage usage = pool->get_memory_usage();
263
264 HOTSPOT_MEM_POOL_GC_END(
265 (char *) name(), strlen(name()),
266 (char *) pool->name(), strlen(pool->name()),
267 usage.init_size(), usage.used(),
268 usage.committed(), usage.max_size());
269
270 _current_gc_stat->set_after_gc_usage(i, usage);
271 }
272
273 // Set last collection usage of the memory pools managed by this collector
274 for (i = 0; i < num_memory_pools(); i++) {
275 MemoryPool* pool = get_memory_pool(i);
276 MemoryUsage usage = pool->get_memory_usage();
277
278 if (allMemoryPoolsAffected || pool_always_affected_by_gc(i)) {
279 // Compare with GC usage threshold
280 pool->set_last_collection_usage(usage);
281 LowMemoryDetector::detect_after_gc_memory(pool);
282 }
283 }
284 }
285
286 if (countCollection) {
287 _num_collections++;
288 // alternately update two objects making one public when complete
289 {
290 MutexLockerEx ml(_last_gc_lock, Mutex::_no_safepoint_check_flag);
291 GCStatInfo *tmp = _last_gc_stat;
292 _last_gc_stat = _current_gc_stat;
293 _current_gc_stat = tmp;
294 // reset the current stat for diagnosability purposes
295 _current_gc_stat->clear();
296 }
297
298 if (is_notification_enabled()) {
299 GCNotifier::pushNotification(this, _gc_end_message, GCCause::to_string(cause));
300 }
301 }
302 }
303
304 size_t GCMemoryManager::get_last_gc_stat(GCStatInfo* dest) {
305 MutexLockerEx ml(_last_gc_lock, Mutex::_no_safepoint_check_flag);
306 if (_last_gc_stat->gc_index() != 0) {
307 dest->set_index(_last_gc_stat->gc_index());
308 dest->set_start_time(_last_gc_stat->start_time());
309 dest->set_end_time(_last_gc_stat->end_time());
310 assert(dest->usage_array_size() == _last_gc_stat->usage_array_size(),
311 "Must have same array size");
312 size_t len = dest->usage_array_size() * sizeof(MemoryUsage);
313 memcpy(dest->before_gc_usage_array(), _last_gc_stat->before_gc_usage_array(), len);
314 memcpy(dest->after_gc_usage_array(), _last_gc_stat->after_gc_usage_array(), len);
315 }
316 return _last_gc_stat->gc_index();
317 }