1 /* 2 * Copyright (c) 2003, 2012, 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 36 #ifdef DTRACE_ENABLED 37 38 // Only bother with this argument setup if dtrace is available 39 40 #ifndef USDT2 41 42 HS_DTRACE_PROBE_DECL4(hotspot, class__loaded, char*, int, oop, bool); 43 HS_DTRACE_PROBE_DECL4(hotspot, class__unloaded, char*, int, oop, bool); 44 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 HS_DTRACE_PROBE4(hotspot, class__##type, \ 55 data, len, (clss)->class_loader(), (shared)); \ 56 } 57 58 #else /* USDT2 */ 59 60 #define HOTSPOT_CLASS_unloaded HOTSPOT_CLASS_UNLOADED 61 #define HOTSPOT_CLASS_loaded HOTSPOT_CLASS_LOADED 62 #define DTRACE_CLASSLOAD_PROBE(type, clss, shared) \ 63 { \ 64 char* data = NULL; \ 65 int len = 0; \ 66 Symbol* name = (clss)->name(); \ 67 if (name != NULL) { \ 68 data = (char*)name->bytes(); \ 69 len = name->utf8_length(); \ 70 } \ 71 HOTSPOT_CLASS_##type( /* type = unloaded, loaded */ \ 72 data, len, (clss)->class_loader(), (shared)); \ 73 } 74 75 #endif /* USDT2 */ 76 #else // ndef DTRACE_ENABLED 77 78 #define DTRACE_CLASSLOAD_PROBE(type, clss, shared) 79 80 #endif 81 82 #if INCLUDE_MANAGEMENT 83 // counters for classes loaded from class files 84 PerfCounter* ClassLoadingService::_classes_loaded_count = NULL; 85 PerfCounter* ClassLoadingService::_classes_unloaded_count = NULL; 86 PerfCounter* ClassLoadingService::_classbytes_loaded = NULL; 87 PerfCounter* ClassLoadingService::_classbytes_unloaded = NULL; 88 89 // counters for classes loaded from shared archive 90 PerfCounter* ClassLoadingService::_shared_classes_loaded_count = NULL; 91 PerfCounter* ClassLoadingService::_shared_classes_unloaded_count = NULL; 92 PerfCounter* ClassLoadingService::_shared_classbytes_loaded = NULL; 93 PerfCounter* ClassLoadingService::_shared_classbytes_unloaded = NULL; 94 PerfVariable* ClassLoadingService::_class_methods_size = NULL; 95 96 void ClassLoadingService::init() { 97 EXCEPTION_MARK; 98 99 // These counters are for java.lang.management API support. 100 // They are created even if -XX:-UsePerfData is set and in 101 // that case, they will be allocated on C heap. 102 _classes_loaded_count = 103 PerfDataManager::create_counter(JAVA_CLS, "loadedClasses", 104 PerfData::U_Events, CHECK); 105 106 _classes_unloaded_count = 107 PerfDataManager::create_counter(JAVA_CLS, "unloadedClasses", 108 PerfData::U_Events, CHECK); 109 110 _shared_classes_loaded_count = 111 PerfDataManager::create_counter(JAVA_CLS, "sharedLoadedClasses", 112 PerfData::U_Events, CHECK); 113 114 _shared_classes_unloaded_count = 115 PerfDataManager::create_counter(JAVA_CLS, "sharedUnloadedClasses", 116 PerfData::U_Events, CHECK); 117 118 if (UsePerfData) { 119 _classbytes_loaded = 120 PerfDataManager::create_counter(SUN_CLS, "loadedBytes", 121 PerfData::U_Bytes, CHECK); 122 123 _classbytes_unloaded = 124 PerfDataManager::create_counter(SUN_CLS, "unloadedBytes", 125 PerfData::U_Bytes, CHECK); 126 _shared_classbytes_loaded = 127 PerfDataManager::create_counter(SUN_CLS, "sharedLoadedBytes", 128 PerfData::U_Bytes, CHECK); 129 130 _shared_classbytes_unloaded = 131 PerfDataManager::create_counter(SUN_CLS, "sharedUnloadedBytes", 132 PerfData::U_Bytes, CHECK); 133 _class_methods_size = 134 PerfDataManager::create_variable(SUN_CLS, "methodBytes", 135 PerfData::U_Bytes, CHECK); 136 } 137 } 138 139 void ClassLoadingService::notify_class_unloaded(InstanceKlass* k) { 140 DTRACE_CLASSLOAD_PROBE(unloaded, k, false); 141 // Classes that can be unloaded must be non-shared 142 _classes_unloaded_count->inc(); 143 144 if (UsePerfData) { 145 // add the class size 146 size_t size = compute_class_size(k); 147 _classbytes_unloaded->inc(size); 148 149 // Compute method size & subtract from running total. 150 // We are called during phase 1 of mark sweep, so it's 151 // still ok to iterate through Method*s here. 152 Array<Method*>* methods = k->methods(); 153 for (int i = 0; i < methods->length(); i++) { 154 _class_methods_size->inc(-methods->at(i)->size()); 155 } 156 } 157 158 if (TraceClassUnloading) { 159 ResourceMark rm; 160 tty->print_cr("[Unloading class %s " INTPTR_FORMAT "]", k->external_name(), k); 161 } 162 } 163 164 void ClassLoadingService::notify_class_loaded(InstanceKlass* k, bool shared_class) { 165 DTRACE_CLASSLOAD_PROBE(loaded, k, shared_class); 166 PerfCounter* classes_counter = (shared_class ? _shared_classes_loaded_count 167 : _classes_loaded_count); 168 // increment the count 169 classes_counter->inc(); 170 171 if (UsePerfData) { 172 PerfCounter* classbytes_counter = (shared_class ? _shared_classbytes_loaded 173 : _classbytes_loaded); 174 // add the class size 175 size_t size = compute_class_size(k); 176 classbytes_counter->inc(size); 177 } 178 } 179 180 size_t ClassLoadingService::compute_class_size(InstanceKlass* k) { 181 // lifted from ClassStatistics.do_class(Klass* k) 182 183 size_t class_size = 0; 184 185 class_size += k->size(); 186 187 if (k->oop_is_instance()) { 188 class_size += k->methods()->size(); 189 // FIXME: Need to count the contents of methods 190 class_size += k->constants()->size(); 191 class_size += k->local_interfaces()->size(); 192 class_size += k->transitive_interfaces()->size(); 193 // We do not have to count implementors, since we only store one! 194 // FIXME: How should these be accounted for, now when they have moved. 195 //class_size += k->fields()->size(); 196 } 197 return class_size * oopSize; 198 } 199 200 201 bool ClassLoadingService::set_verbose(bool verbose) { 202 MutexLocker m(Management_lock); 203 204 // verbose will be set to the previous value 205 bool succeed = CommandLineFlags::boolAtPut((char*)"TraceClassLoading", &verbose, Flag::MANAGEMENT); 206 assert(succeed, "Setting TraceClassLoading flag fails"); 207 reset_trace_class_unloading(); 208 209 return verbose; 210 } 211 212 // Caller to this function must own Management_lock 213 void ClassLoadingService::reset_trace_class_unloading() { 214 assert(Management_lock->owned_by_self(), "Must own the Management_lock"); 215 bool value = MemoryService::get_verbose() || ClassLoadingService::get_verbose(); 216 bool succeed = CommandLineFlags::boolAtPut((char*)"TraceClassUnloading", &value, Flag::MANAGEMENT); 217 assert(succeed, "Setting TraceClassUnLoading flag fails"); 218 } 219 220 GrowableArray<KlassHandle>* LoadedClassesEnumerator::_loaded_classes = NULL; 221 Thread* LoadedClassesEnumerator::_current_thread = NULL; 222 223 LoadedClassesEnumerator::LoadedClassesEnumerator(Thread* cur_thread) { 224 assert(cur_thread == Thread::current(), "Check current thread"); 225 226 int init_size = ClassLoadingService::loaded_class_count(); 227 _klass_handle_array = new GrowableArray<KlassHandle>(init_size); 228 229 // For consistency of the loaded classes, grab the SystemDictionary lock 230 MutexLocker sd_mutex(SystemDictionary_lock); 231 232 // Set _loaded_classes and _current_thread and begin enumerating all classes. 233 // Only one thread will do the enumeration at a time. 234 // These static variables are needed and they are used by the static method 235 // add_loaded_class called from classes_do(). 236 _loaded_classes = _klass_handle_array; 237 _current_thread = cur_thread; 238 239 SystemDictionary::classes_do(&add_loaded_class); 240 241 // FIXME: Exclude array klasses for now 242 // Universe::basic_type_classes_do(&add_loaded_class); 243 } 244 245 #endif // INCLUDE_MANAGEMENT