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