1 /*
2 * Copyright (c) 2003, 2016, 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 "memory/allocation.hpp"
28 #include "memory/universe.hpp"
29 #include "oops/oop.inline.hpp"
30 #include "runtime/mutexLocker.hpp"
31 #include "services/classLoadingService.hpp"
32 #include "services/memoryService.hpp"
33 #include "utilities/dtrace.hpp"
34 #include "utilities/macros.hpp"
35 #include "utilities/defaultStream.hpp"
36 #include "logging/log.hpp"
37 #include "logging/logConfiguration.hpp"
38
39 #ifdef DTRACE_ENABLED
40
41 // Only bother with this argument setup if dtrace is available
42
43 #define HOTSPOT_CLASS_unloaded HOTSPOT_CLASS_UNLOADED
44 #define HOTSPOT_CLASS_loaded HOTSPOT_CLASS_LOADED
45 #define DTRACE_CLASSLOAD_PROBE(type, clss, shared) \
46 { \
47 char* data = NULL; \
48 int len = 0; \
49 Symbol* name = (clss)->name(); \
50 if (name != NULL) { \
51 data = (char*)name->bytes(); \
52 len = name->utf8_length(); \
53 } \
54 HOTSPOT_CLASS_##type( /* type = unloaded, loaded */ \
55 data, len, (clss)->class_loader(), (shared)); \
56 }
57
58 #else // ndef DTRACE_ENABLED
59
60 #define DTRACE_CLASSLOAD_PROBE(type, clss, shared)
61
62 #endif
63
64 #if INCLUDE_MANAGEMENT
65 // counters for classes loaded from class files
66 PerfCounter* ClassLoadingService::_classes_loaded_count = NULL;
67 PerfCounter* ClassLoadingService::_classes_unloaded_count = NULL;
68 PerfCounter* ClassLoadingService::_classbytes_loaded = NULL;
69 PerfCounter* ClassLoadingService::_classbytes_unloaded = NULL;
70
71 // counters for classes loaded from shared archive
72 PerfCounter* ClassLoadingService::_shared_classes_loaded_count = NULL;
73 PerfCounter* ClassLoadingService::_shared_classes_unloaded_count = NULL;
74 PerfCounter* ClassLoadingService::_shared_classbytes_loaded = NULL;
75 PerfCounter* ClassLoadingService::_shared_classbytes_unloaded = NULL;
76 PerfVariable* ClassLoadingService::_class_methods_size = NULL;
77
78 void ClassLoadingService::init() {
79 EXCEPTION_MARK;
80
81 // These counters are for java.lang.management API support.
82 // They are created even if -XX:-UsePerfData is set and in
83 // that case, they will be allocated on C heap.
84 _classes_loaded_count =
85 PerfDataManager::create_counter(JAVA_CLS, "loadedClasses",
86 PerfData::U_Events, CHECK);
87
88 _classes_unloaded_count =
89 PerfDataManager::create_counter(JAVA_CLS, "unloadedClasses",
90 PerfData::U_Events, CHECK);
91
92 _shared_classes_loaded_count =
93 PerfDataManager::create_counter(JAVA_CLS, "sharedLoadedClasses",
94 PerfData::U_Events, CHECK);
95
96 _shared_classes_unloaded_count =
97 PerfDataManager::create_counter(JAVA_CLS, "sharedUnloadedClasses",
98 PerfData::U_Events, CHECK);
99
100 if (UsePerfData) {
101 _classbytes_loaded =
102 PerfDataManager::create_counter(SUN_CLS, "loadedBytes",
103 PerfData::U_Bytes, CHECK);
104
105 _classbytes_unloaded =
106 PerfDataManager::create_counter(SUN_CLS, "unloadedBytes",
107 PerfData::U_Bytes, CHECK);
108 _shared_classbytes_loaded =
109 PerfDataManager::create_counter(SUN_CLS, "sharedLoadedBytes",
110 PerfData::U_Bytes, CHECK);
111
112 _shared_classbytes_unloaded =
113 PerfDataManager::create_counter(SUN_CLS, "sharedUnloadedBytes",
114 PerfData::U_Bytes, CHECK);
115 _class_methods_size =
116 PerfDataManager::create_variable(SUN_CLS, "methodBytes",
117 PerfData::U_Bytes, CHECK);
118 }
119 }
120
121 void ClassLoadingService::notify_class_unloaded(InstanceKlass* k) {
122 DTRACE_CLASSLOAD_PROBE(unloaded, k, false);
123 // Classes that can be unloaded must be non-shared
124 _classes_unloaded_count->inc();
125
126 if (UsePerfData) {
127 // add the class size
128 size_t size = compute_class_size(k);
129 _classbytes_unloaded->inc(size);
130
131 // Compute method size & subtract from running total.
132 // We are called during phase 1 of mark sweep, so it's
133 // still ok to iterate through Method*s here.
134 Array<Method*>* methods = k->methods();
135 for (int i = 0; i < methods->length(); i++) {
136 _class_methods_size->inc(-methods->at(i)->size());
137 }
138 }
139
140 if (log_is_enabled(Info, classunload)) {
141 ResourceMark rm;
142 log_info(classunload)("unloading class %s " INTPTR_FORMAT , k->external_name(), p2i(k));
143 }
144 }
145
146 void ClassLoadingService::notify_class_loaded(InstanceKlass* k, bool shared_class) {
147 DTRACE_CLASSLOAD_PROBE(loaded, k, shared_class);
148 PerfCounter* classes_counter = (shared_class ? _shared_classes_loaded_count
149 : _classes_loaded_count);
150 // increment the count
151 classes_counter->inc();
152
153 if (UsePerfData) {
154 PerfCounter* classbytes_counter = (shared_class ? _shared_classbytes_loaded
155 : _classbytes_loaded);
156 // add the class size
157 size_t size = compute_class_size(k);
158 classbytes_counter->inc(size);
159 }
160 }
161
162 size_t ClassLoadingService::compute_class_size(InstanceKlass* k) {
163 // lifted from ClassStatistics.do_class(Klass* k)
164
165 size_t class_size = 0;
166
167 class_size += k->size();
168
169 if (k->is_instance_klass()) {
170 class_size += k->methods()->size();
171 // FIXME: Need to count the contents of methods
172 class_size += k->constants()->size();
173 class_size += k->local_interfaces()->size();
174 class_size += k->transitive_interfaces()->size();
175 // We do not have to count implementors, since we only store one!
176 // FIXME: How should these be accounted for, now when they have moved.
177 //class_size += k->fields()->size();
178 }
179 return class_size * oopSize;
180 }
181
182 bool ClassLoadingService::set_verbose(bool verbose) {
183 MutexLocker m(Management_lock);
184 // verbose will be set to the previous value
185 if (verbose) {
186 LogConfiguration::parse_log_arguments("stdout", "classload=info", NULL, NULL, NULL);
187 } else {
188 LogConfiguration::parse_log_arguments("stdout", "classload=off", NULL, NULL, NULL);
189 }
190 reset_trace_class_unloading();
191 return verbose;
192 }
193
194 // Caller to this function must own Management_lock
195 void ClassLoadingService::reset_trace_class_unloading() {
196 bool ret;
197 assert(Management_lock->owned_by_self(), "Must own the Management_lock");
198 bool value = MemoryService::get_verbose() || ClassLoadingService::get_verbose();
199 if (value) {
200 ret = LogConfiguration::parse_log_arguments("stdout", "classunload=info", NULL, NULL, NULL);
201 } else {
202 ret = LogConfiguration::parse_log_arguments("stdout", "classunload=off", NULL, NULL, NULL);
203 }
204 }
205
206 GrowableArray<KlassHandle>* LoadedClassesEnumerator::_loaded_classes = NULL;
207 Thread* LoadedClassesEnumerator::_current_thread = NULL;
208
209 LoadedClassesEnumerator::LoadedClassesEnumerator(Thread* cur_thread) {
210 assert(cur_thread == Thread::current(), "Check current thread");
211
212 int init_size = ClassLoadingService::loaded_class_count();
213 _klass_handle_array = new GrowableArray<KlassHandle>(init_size);
214
215 // For consistency of the loaded classes, grab the SystemDictionary lock
216 MutexLocker sd_mutex(SystemDictionary_lock);
217
218 // Set _loaded_classes and _current_thread and begin enumerating all classes.
219 // Only one thread will do the enumeration at a time.
220 // These static variables are needed and they are used by the static method
221 // add_loaded_class called from classes_do().
222 _loaded_classes = _klass_handle_array;
223 _current_thread = cur_thread;
224
225 SystemDictionary::classes_do(&add_loaded_class);
226
227 // FIXME: Exclude array klasses for now
228 // Universe::basic_type_classes_do(&add_loaded_class);
229 }
230
231 #endif // INCLUDE_MANAGEMENT