Mercurial > hg > truffle
annotate src/share/vm/classfile/systemDictionary.cpp @ 196:d1605aabd0a1 jdk7-b30
6719955: Update copyright year
Summary: Update copyright year for files that have been modified in 2008
Reviewed-by: ohair, tbell
| author | xdono |
|---|---|
| date | Wed, 02 Jul 2008 12:55:16 -0700 |
| parents | 60b728ec77c1 |
| children | a45484ea312d |
| rev | line source |
|---|---|
| 0 | 1 /* |
| 196 | 2 * Copyright 1997-2008 Sun Microsystems, Inc. All Rights Reserved. |
| 0 | 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, | |
| 20 * CA 95054 USA or visit www.sun.com if you need additional information or | |
| 21 * have any questions. | |
| 22 * | |
| 23 */ | |
| 24 | |
| 25 # include "incls/_precompiled.incl" | |
| 26 # include "incls/_systemDictionary.cpp.incl" | |
| 27 | |
| 28 | |
| 29 Dictionary* SystemDictionary::_dictionary = NULL; | |
| 30 PlaceholderTable* SystemDictionary::_placeholders = NULL; | |
| 31 Dictionary* SystemDictionary::_shared_dictionary = NULL; | |
| 32 LoaderConstraintTable* SystemDictionary::_loader_constraints = NULL; | |
| 33 ResolutionErrorTable* SystemDictionary::_resolution_errors = NULL; | |
| 34 | |
| 35 | |
| 36 int SystemDictionary::_number_of_modifications = 0; | |
| 37 | |
| 38 oop SystemDictionary::_system_loader_lock_obj = NULL; | |
| 39 | |
|
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40 klassOop SystemDictionary::_well_known_klasses[SystemDictionary::WKID_LIMIT] |
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41 = { NULL /*, NULL...*/ }; |
| 0 | 42 |
| 43 klassOop SystemDictionary::_box_klasses[T_VOID+1] = { NULL /*, NULL...*/ }; | |
| 44 | |
| 45 oop SystemDictionary::_java_system_loader = NULL; | |
| 46 | |
| 47 bool SystemDictionary::_has_loadClassInternal = false; | |
| 48 bool SystemDictionary::_has_checkPackageAccess = false; | |
| 49 | |
| 50 // lazily initialized klass variables | |
| 51 volatile klassOop SystemDictionary::_abstract_ownable_synchronizer_klass = NULL; | |
| 52 | |
| 53 | |
| 54 // ---------------------------------------------------------------------------- | |
| 55 // Java-level SystemLoader | |
| 56 | |
| 57 oop SystemDictionary::java_system_loader() { | |
| 58 return _java_system_loader; | |
| 59 } | |
| 60 | |
| 61 void SystemDictionary::compute_java_system_loader(TRAPS) { | |
|
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62 KlassHandle system_klass(THREAD, WK_KLASS(classloader_klass)); |
| 0 | 63 JavaValue result(T_OBJECT); |
| 64 JavaCalls::call_static(&result, | |
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65 KlassHandle(THREAD, WK_KLASS(classloader_klass)), |
| 0 | 66 vmSymbolHandles::getSystemClassLoader_name(), |
| 67 vmSymbolHandles::void_classloader_signature(), | |
| 68 CHECK); | |
| 69 | |
| 70 _java_system_loader = (oop)result.get_jobject(); | |
| 71 } | |
| 72 | |
| 73 | |
| 74 // ---------------------------------------------------------------------------- | |
| 75 // debugging | |
| 76 | |
| 77 #ifdef ASSERT | |
| 78 | |
| 79 // return true if class_name contains no '.' (internal format is '/') | |
| 80 bool SystemDictionary::is_internal_format(symbolHandle class_name) { | |
| 81 if (class_name.not_null()) { | |
| 82 ResourceMark rm; | |
| 83 char* name = class_name->as_C_string(); | |
| 84 return strchr(name, '.') == NULL; | |
| 85 } else { | |
| 86 return true; | |
| 87 } | |
| 88 } | |
| 89 | |
| 90 #endif | |
| 91 | |
| 92 // ---------------------------------------------------------------------------- | |
| 93 // Resolving of classes | |
| 94 | |
| 95 // Forwards to resolve_or_null | |
| 96 | |
| 97 klassOop SystemDictionary::resolve_or_fail(symbolHandle class_name, Handle class_loader, Handle protection_domain, bool throw_error, TRAPS) { | |
| 98 klassOop klass = resolve_or_null(class_name, class_loader, protection_domain, THREAD); | |
| 99 if (HAS_PENDING_EXCEPTION || klass == NULL) { | |
| 100 KlassHandle k_h(THREAD, klass); | |
| 101 // can return a null klass | |
| 102 klass = handle_resolution_exception(class_name, class_loader, protection_domain, throw_error, k_h, THREAD); | |
| 103 } | |
| 104 return klass; | |
| 105 } | |
| 106 | |
| 107 klassOop SystemDictionary::handle_resolution_exception(symbolHandle class_name, Handle class_loader, Handle protection_domain, bool throw_error, KlassHandle klass_h, TRAPS) { | |
| 108 if (HAS_PENDING_EXCEPTION) { | |
| 109 // If we have a pending exception we forward it to the caller, unless throw_error is true, | |
| 110 // in which case we have to check whether the pending exception is a ClassNotFoundException, | |
| 111 // and if so convert it to a NoClassDefFoundError | |
| 112 // And chain the original ClassNotFoundException | |
| 113 if (throw_error && PENDING_EXCEPTION->is_a(SystemDictionary::classNotFoundException_klass())) { | |
| 114 ResourceMark rm(THREAD); | |
| 115 assert(klass_h() == NULL, "Should not have result with exception pending"); | |
| 116 Handle e(THREAD, PENDING_EXCEPTION); | |
| 117 CLEAR_PENDING_EXCEPTION; | |
| 118 THROW_MSG_CAUSE_0(vmSymbols::java_lang_NoClassDefFoundError(), class_name->as_C_string(), e); | |
| 119 } else { | |
| 120 return NULL; | |
| 121 } | |
| 122 } | |
| 123 // Class not found, throw appropriate error or exception depending on value of throw_error | |
| 124 if (klass_h() == NULL) { | |
| 125 ResourceMark rm(THREAD); | |
| 126 if (throw_error) { | |
| 127 THROW_MSG_0(vmSymbols::java_lang_NoClassDefFoundError(), class_name->as_C_string()); | |
| 128 } else { | |
| 129 THROW_MSG_0(vmSymbols::java_lang_ClassNotFoundException(), class_name->as_C_string()); | |
| 130 } | |
| 131 } | |
| 132 return (klassOop)klass_h(); | |
| 133 } | |
| 134 | |
| 135 | |
| 136 klassOop SystemDictionary::resolve_or_fail(symbolHandle class_name, | |
| 137 bool throw_error, TRAPS) | |
| 138 { | |
| 139 return resolve_or_fail(class_name, Handle(), Handle(), throw_error, THREAD); | |
| 140 } | |
| 141 | |
| 142 | |
| 143 // Forwards to resolve_instance_class_or_null | |
| 144 | |
| 145 klassOop SystemDictionary::resolve_or_null(symbolHandle class_name, Handle class_loader, Handle protection_domain, TRAPS) { | |
| 146 assert(!THREAD->is_Compiler_thread(), "Can not load classes with the Compiler thread"); | |
| 147 if (FieldType::is_array(class_name())) { | |
| 148 return resolve_array_class_or_null(class_name, class_loader, protection_domain, CHECK_NULL); | |
| 149 } else { | |
| 150 return resolve_instance_class_or_null(class_name, class_loader, protection_domain, CHECK_NULL); | |
| 151 } | |
| 152 } | |
| 153 | |
| 154 klassOop SystemDictionary::resolve_or_null(symbolHandle class_name, TRAPS) { | |
| 155 return resolve_or_null(class_name, Handle(), Handle(), THREAD); | |
| 156 } | |
| 157 | |
| 158 // Forwards to resolve_instance_class_or_null | |
| 159 | |
| 160 klassOop SystemDictionary::resolve_array_class_or_null(symbolHandle class_name, | |
| 161 Handle class_loader, | |
| 162 Handle protection_domain, | |
| 163 TRAPS) { | |
| 164 assert(FieldType::is_array(class_name()), "must be array"); | |
| 165 jint dimension; | |
| 166 symbolOop object_key; | |
| 167 klassOop k = NULL; | |
| 168 // dimension and object_key are assigned as a side-effect of this call | |
| 169 BasicType t = FieldType::get_array_info(class_name(), | |
| 170 &dimension, | |
| 171 &object_key, | |
| 172 CHECK_NULL); | |
| 173 | |
| 174 if (t == T_OBJECT) { | |
| 175 symbolHandle h_key(THREAD, object_key); | |
| 176 // naked oop "k" is OK here -- we assign back into it | |
| 177 k = SystemDictionary::resolve_instance_class_or_null(h_key, | |
| 178 class_loader, | |
| 179 protection_domain, | |
| 180 CHECK_NULL); | |
| 181 if (k != NULL) { | |
| 182 k = Klass::cast(k)->array_klass(dimension, CHECK_NULL); | |
| 183 } | |
| 184 } else { | |
| 185 k = Universe::typeArrayKlassObj(t); | |
| 186 k = typeArrayKlass::cast(k)->array_klass(dimension, CHECK_NULL); | |
| 187 } | |
| 188 return k; | |
| 189 } | |
| 190 | |
| 191 | |
| 192 // Must be called for any super-class or super-interface resolution | |
| 193 // during class definition to allow class circularity checking | |
| 194 // super-interface callers: | |
| 195 // parse_interfaces - for defineClass & jvmtiRedefineClasses | |
| 196 // super-class callers: | |
| 197 // ClassFileParser - for defineClass & jvmtiRedefineClasses | |
| 198 // load_shared_class - while loading a class from shared archive | |
| 199 // resolve_instance_class_or_fail: | |
| 200 // when resolving a class that has an existing placeholder with | |
| 201 // a saved superclass [i.e. a defineClass is currently in progress] | |
| 202 // if another thread is trying to resolve the class, it must do | |
| 203 // super-class checks on its own thread to catch class circularity | |
| 204 // This last call is critical in class circularity checking for cases | |
| 205 // where classloading is delegated to different threads and the | |
| 206 // classloader lock is released. | |
| 207 // Take the case: Base->Super->Base | |
| 208 // 1. If thread T1 tries to do a defineClass of class Base | |
| 209 // resolve_super_or_fail creates placeholder: T1, Base (super Super) | |
| 210 // 2. resolve_instance_class_or_null does not find SD or placeholder for Super | |
| 211 // so it tries to load Super | |
| 212 // 3. If we load the class internally, or user classloader uses same thread | |
| 213 // loadClassFromxxx or defineClass via parseClassFile Super ... | |
| 214 // 3.1 resolve_super_or_fail creates placeholder: T1, Super (super Base) | |
| 215 // 3.3 resolve_instance_class_or_null Base, finds placeholder for Base | |
| 216 // 3.4 calls resolve_super_or_fail Base | |
| 217 // 3.5 finds T1,Base -> throws class circularity | |
| 218 //OR 4. If T2 tries to resolve Super via defineClass Super ... | |
| 219 // 4.1 resolve_super_or_fail creates placeholder: T2, Super (super Base) | |
| 220 // 4.2 resolve_instance_class_or_null Base, finds placeholder for Base (super Super) | |
| 221 // 4.3 calls resolve_super_or_fail Super in parallel on own thread T2 | |
| 222 // 4.4 finds T2, Super -> throws class circularity | |
| 223 // Must be called, even if superclass is null, since this is | |
| 224 // where the placeholder entry is created which claims this | |
| 225 // thread is loading this class/classloader. | |
| 226 klassOop SystemDictionary::resolve_super_or_fail(symbolHandle child_name, | |
| 227 symbolHandle class_name, | |
| 228 Handle class_loader, | |
| 229 Handle protection_domain, | |
| 230 bool is_superclass, | |
| 231 TRAPS) { | |
| 232 | |
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233 // Try to get one of the well-known klasses. |
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234 // They are trusted, and do not participate in circularities. |
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235 if (LinkWellKnownClasses) { |
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236 klassOop k = find_well_known_klass(class_name()); |
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237 if (k != NULL) { |
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238 return k; |
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239 } |
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240 } |
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241 |
| 0 | 242 // Double-check, if child class is already loaded, just return super-class,interface |
| 243 // Don't add a placedholder if already loaded, i.e. already in system dictionary | |
| 244 // Make sure there's a placeholder for the *child* before resolving. | |
| 245 // Used as a claim that this thread is currently loading superclass/classloader | |
| 246 // Used here for ClassCircularity checks and also for heap verification | |
| 247 // (every instanceKlass in the heap needs to be in the system dictionary | |
| 248 // or have a placeholder). | |
| 249 // Must check ClassCircularity before checking if super class is already loaded | |
| 250 // | |
| 251 // We might not already have a placeholder if this child_name was | |
| 252 // first seen via resolve_from_stream (jni_DefineClass or JVM_DefineClass); | |
| 253 // the name of the class might not be known until the stream is actually | |
| 254 // parsed. | |
| 255 // Bugs 4643874, 4715493 | |
| 256 // compute_hash can have a safepoint | |
| 257 | |
| 258 unsigned int d_hash = dictionary()->compute_hash(child_name, class_loader); | |
| 259 int d_index = dictionary()->hash_to_index(d_hash); | |
| 260 unsigned int p_hash = placeholders()->compute_hash(child_name, class_loader); | |
| 261 int p_index = placeholders()->hash_to_index(p_hash); | |
| 262 // can't throw error holding a lock | |
| 263 bool child_already_loaded = false; | |
| 264 bool throw_circularity_error = false; | |
| 265 { | |
| 266 MutexLocker mu(SystemDictionary_lock, THREAD); | |
| 267 klassOop childk = find_class(d_index, d_hash, child_name, class_loader); | |
| 268 klassOop quicksuperk; | |
| 269 // to support // loading: if child done loading, just return superclass | |
| 270 // if class_name, & class_loader don't match: | |
| 271 // if initial define, SD update will give LinkageError | |
| 272 // if redefine: compare_class_versions will give HIERARCHY_CHANGED | |
| 273 // so we don't throw an exception here. | |
| 274 // see: nsk redefclass014 & java.lang.instrument Instrument032 | |
| 275 if ((childk != NULL ) && (is_superclass) && | |
| 276 ((quicksuperk = instanceKlass::cast(childk)->super()) != NULL) && | |
| 277 | |
| 278 ((Klass::cast(quicksuperk)->name() == class_name()) && | |
| 279 (Klass::cast(quicksuperk)->class_loader() == class_loader()))) { | |
| 280 return quicksuperk; | |
| 281 } else { | |
| 282 PlaceholderEntry* probe = placeholders()->get_entry(p_index, p_hash, child_name, class_loader); | |
| 283 if (probe && probe->check_seen_thread(THREAD, PlaceholderTable::LOAD_SUPER)) { | |
| 284 throw_circularity_error = true; | |
| 285 } | |
| 286 | |
| 287 // add placeholder entry even if error - callers will remove on error | |
| 288 PlaceholderEntry* newprobe = placeholders()->find_and_add(p_index, p_hash, child_name, class_loader, PlaceholderTable::LOAD_SUPER, class_name, THREAD); | |
| 289 if (throw_circularity_error) { | |
| 290 newprobe->remove_seen_thread(THREAD, PlaceholderTable::LOAD_SUPER); | |
| 291 } | |
| 292 } | |
| 293 } | |
| 294 if (throw_circularity_error) { | |
| 295 ResourceMark rm(THREAD); | |
| 296 THROW_MSG_0(vmSymbols::java_lang_ClassCircularityError(), child_name->as_C_string()); | |
| 297 } | |
| 298 | |
| 299 // java.lang.Object should have been found above | |
| 300 assert(class_name() != NULL, "null super class for resolving"); | |
| 301 // Resolve the super class or interface, check results on return | |
| 302 klassOop superk = NULL; | |
| 303 superk = SystemDictionary::resolve_or_null(class_name, | |
| 304 class_loader, | |
| 305 protection_domain, | |
| 306 THREAD); | |
| 307 | |
| 308 KlassHandle superk_h(THREAD, superk); | |
| 309 | |
| 310 // Note: clean up of placeholders currently in callers of | |
| 311 // resolve_super_or_fail - either at update_dictionary time | |
| 312 // or on error | |
| 313 { | |
| 314 MutexLocker mu(SystemDictionary_lock, THREAD); | |
| 315 PlaceholderEntry* probe = placeholders()->get_entry(p_index, p_hash, child_name, class_loader); | |
| 316 if (probe != NULL) { | |
| 317 probe->remove_seen_thread(THREAD, PlaceholderTable::LOAD_SUPER); | |
| 318 } | |
| 319 } | |
| 320 if (HAS_PENDING_EXCEPTION || superk_h() == NULL) { | |
| 321 // can null superk | |
| 322 superk_h = KlassHandle(THREAD, handle_resolution_exception(class_name, class_loader, protection_domain, true, superk_h, THREAD)); | |
| 323 } | |
| 324 | |
| 325 return superk_h(); | |
| 326 } | |
| 327 | |
| 328 | |
| 329 void SystemDictionary::validate_protection_domain(instanceKlassHandle klass, | |
| 330 Handle class_loader, | |
| 331 Handle protection_domain, | |
| 332 TRAPS) { | |
| 333 if(!has_checkPackageAccess()) return; | |
| 334 | |
| 335 // Now we have to call back to java to check if the initating class has access | |
| 336 JavaValue result(T_VOID); | |
| 337 if (TraceProtectionDomainVerification) { | |
| 338 // Print out trace information | |
| 339 tty->print_cr("Checking package access"); | |
| 340 tty->print(" - class loader: "); class_loader()->print_value_on(tty); tty->cr(); | |
| 341 tty->print(" - protection domain: "); protection_domain()->print_value_on(tty); tty->cr(); | |
| 342 tty->print(" - loading: "); klass()->print_value_on(tty); tty->cr(); | |
| 343 } | |
| 344 | |
| 345 assert(class_loader() != NULL, "should not have non-null protection domain for null classloader"); | |
| 346 | |
| 347 KlassHandle system_loader(THREAD, SystemDictionary::classloader_klass()); | |
| 348 JavaCalls::call_special(&result, | |
| 349 class_loader, | |
| 350 system_loader, | |
| 351 vmSymbolHandles::checkPackageAccess_name(), | |
| 352 vmSymbolHandles::class_protectiondomain_signature(), | |
| 353 Handle(THREAD, klass->java_mirror()), | |
| 354 protection_domain, | |
| 355 THREAD); | |
| 356 | |
| 357 if (TraceProtectionDomainVerification) { | |
| 358 if (HAS_PENDING_EXCEPTION) { | |
| 359 tty->print_cr(" -> DENIED !!!!!!!!!!!!!!!!!!!!!"); | |
| 360 } else { | |
| 361 tty->print_cr(" -> granted"); | |
| 362 } | |
| 363 tty->cr(); | |
| 364 } | |
| 365 | |
| 366 if (HAS_PENDING_EXCEPTION) return; | |
| 367 | |
| 368 // If no exception has been thrown, we have validated the protection domain | |
| 369 // Insert the protection domain of the initiating class into the set. | |
| 370 { | |
| 371 // We recalculate the entry here -- we've called out to java since | |
| 372 // the last time it was calculated. | |
| 373 symbolHandle kn(THREAD, klass->name()); | |
| 374 unsigned int d_hash = dictionary()->compute_hash(kn, class_loader); | |
| 375 int d_index = dictionary()->hash_to_index(d_hash); | |
| 376 | |
| 377 MutexLocker mu(SystemDictionary_lock, THREAD); | |
| 378 { | |
| 379 // Note that we have an entry, and entries can be deleted only during GC, | |
| 380 // so we cannot allow GC to occur while we're holding this entry. | |
| 381 | |
| 382 // We're using a No_Safepoint_Verifier to catch any place where we | |
| 383 // might potentially do a GC at all. | |
| 384 // SystemDictionary::do_unloading() asserts that classes are only | |
| 385 // unloaded at a safepoint. | |
| 386 No_Safepoint_Verifier nosafepoint; | |
| 387 dictionary()->add_protection_domain(d_index, d_hash, klass, class_loader, | |
| 388 protection_domain, THREAD); | |
| 389 } | |
| 390 } | |
| 391 } | |
| 392 | |
| 393 // We only get here if this thread finds that another thread | |
| 394 // has already claimed the placeholder token for the current operation, | |
| 395 // but that other thread either never owned or gave up the | |
| 396 // object lock | |
| 397 // Waits on SystemDictionary_lock to indicate placeholder table updated | |
| 398 // On return, caller must recheck placeholder table state | |
| 399 // | |
| 400 // We only get here if | |
| 401 // 1) custom classLoader, i.e. not bootstrap classloader | |
| 402 // 2) UnsyncloadClass not set | |
| 403 // 3) custom classLoader has broken the class loader objectLock | |
| 404 // so another thread got here in parallel | |
| 405 // | |
| 406 // lockObject must be held. | |
| 407 // Complicated dance due to lock ordering: | |
| 408 // Must first release the classloader object lock to | |
| 409 // allow initial definer to complete the class definition | |
| 410 // and to avoid deadlock | |
| 411 // Reclaim classloader lock object with same original recursion count | |
| 412 // Must release SystemDictionary_lock after notify, since | |
| 413 // class loader lock must be claimed before SystemDictionary_lock | |
| 414 // to prevent deadlocks | |
| 415 // | |
| 416 // The notify allows applications that did an untimed wait() on | |
| 417 // the classloader object lock to not hang. | |
| 418 void SystemDictionary::double_lock_wait(Handle lockObject, TRAPS) { | |
| 419 assert_lock_strong(SystemDictionary_lock); | |
| 420 | |
| 421 bool calledholdinglock | |
| 422 = ObjectSynchronizer::current_thread_holds_lock((JavaThread*)THREAD, lockObject); | |
| 423 assert(calledholdinglock,"must hold lock for notify"); | |
| 424 assert(!UnsyncloadClass, "unexpected double_lock_wait"); | |
| 425 ObjectSynchronizer::notifyall(lockObject, THREAD); | |
| 426 intptr_t recursions = ObjectSynchronizer::complete_exit(lockObject, THREAD); | |
| 427 SystemDictionary_lock->wait(); | |
| 428 SystemDictionary_lock->unlock(); | |
| 429 ObjectSynchronizer::reenter(lockObject, recursions, THREAD); | |
| 430 SystemDictionary_lock->lock(); | |
| 431 } | |
| 432 | |
| 433 // If the class in is in the placeholder table, class loading is in progress | |
| 434 // For cases where the application changes threads to load classes, it | |
| 435 // is critical to ClassCircularity detection that we try loading | |
| 436 // the superclass on the same thread internally, so we do parallel | |
| 437 // super class loading here. | |
| 438 // This also is critical in cases where the original thread gets stalled | |
| 439 // even in non-circularity situations. | |
| 440 // Note: only one thread can define the class, but multiple can resolve | |
| 441 // Note: must call resolve_super_or_fail even if null super - | |
| 442 // to force placeholder entry creation for this class | |
| 443 // Caller must check for pending exception | |
| 444 // Returns non-null klassOop if other thread has completed load | |
| 445 // and we are done, | |
| 446 // If return null klassOop and no pending exception, the caller must load the class | |
| 447 instanceKlassHandle SystemDictionary::handle_parallel_super_load( | |
| 448 symbolHandle name, symbolHandle superclassname, Handle class_loader, | |
| 449 Handle protection_domain, Handle lockObject, TRAPS) { | |
| 450 | |
| 451 instanceKlassHandle nh = instanceKlassHandle(); // null Handle | |
| 452 unsigned int d_hash = dictionary()->compute_hash(name, class_loader); | |
| 453 int d_index = dictionary()->hash_to_index(d_hash); | |
| 454 unsigned int p_hash = placeholders()->compute_hash(name, class_loader); | |
| 455 int p_index = placeholders()->hash_to_index(p_hash); | |
| 456 | |
| 457 // superk is not used, resolve_super called for circularity check only | |
| 458 // This code is reached in two situations. One if this thread | |
| 459 // is loading the same class twice (e.g. ClassCircularity, or | |
| 460 // java.lang.instrument). | |
| 461 // The second is if another thread started the resolve_super first | |
| 462 // and has not yet finished. | |
| 463 // In both cases the original caller will clean up the placeholder | |
| 464 // entry on error. | |
| 465 klassOop superk = SystemDictionary::resolve_super_or_fail(name, | |
| 466 superclassname, | |
| 467 class_loader, | |
| 468 protection_domain, | |
| 469 true, | |
| 470 CHECK_(nh)); | |
| 471 // We don't redefine the class, so we just need to clean up if there | |
| 472 // was not an error (don't want to modify any system dictionary | |
| 473 // data structures). | |
| 474 { | |
| 475 MutexLocker mu(SystemDictionary_lock, THREAD); | |
| 476 placeholders()->find_and_remove(p_index, p_hash, name, class_loader, THREAD); | |
| 477 SystemDictionary_lock->notify_all(); | |
| 478 } | |
| 479 | |
| 480 // UnsyncloadClass does NOT wait for parallel superclass loads to complete | |
| 481 // Bootstrap classloader does wait for parallel superclass loads | |
| 482 if (UnsyncloadClass) { | |
| 483 MutexLocker mu(SystemDictionary_lock, THREAD); | |
| 484 // Check if classloading completed while we were loading superclass or waiting | |
| 485 klassOop check = find_class(d_index, d_hash, name, class_loader); | |
| 486 if (check != NULL) { | |
| 487 // Klass is already loaded, so just return it | |
| 488 return(instanceKlassHandle(THREAD, check)); | |
| 489 } else { | |
| 490 return nh; | |
| 491 } | |
| 492 } | |
| 493 | |
| 494 // must loop to both handle other placeholder updates | |
| 495 // and spurious notifications | |
| 496 bool super_load_in_progress = true; | |
| 497 PlaceholderEntry* placeholder; | |
| 498 while (super_load_in_progress) { | |
| 499 MutexLocker mu(SystemDictionary_lock, THREAD); | |
| 500 // Check if classloading completed while we were loading superclass or waiting | |
| 501 klassOop check = find_class(d_index, d_hash, name, class_loader); | |
| 502 if (check != NULL) { | |
| 503 // Klass is already loaded, so just return it | |
| 504 return(instanceKlassHandle(THREAD, check)); | |
| 505 } else { | |
| 506 placeholder = placeholders()->get_entry(p_index, p_hash, name, class_loader); | |
| 507 if (placeholder && placeholder->super_load_in_progress() ){ | |
| 508 // Before UnsyncloadClass: | |
| 509 // We only get here if the application has released the | |
| 510 // classloader lock when another thread was in the middle of loading a | |
| 511 // superclass/superinterface for this class, and now | |
| 512 // this thread is also trying to load this class. | |
| 513 // To minimize surprises, the first thread that started to | |
| 514 // load a class should be the one to complete the loading | |
| 515 // with the classfile it initially expected. | |
| 516 // This logic has the current thread wait once it has done | |
| 517 // all the superclass/superinterface loading it can, until | |
| 518 // the original thread completes the class loading or fails | |
| 519 // If it completes we will use the resulting instanceKlass | |
| 520 // which we will find below in the systemDictionary. | |
| 521 // We also get here for parallel bootstrap classloader | |
| 522 if (class_loader.is_null()) { | |
| 523 SystemDictionary_lock->wait(); | |
| 524 } else { | |
| 525 double_lock_wait(lockObject, THREAD); | |
| 526 } | |
| 527 } else { | |
| 528 // If not in SD and not in PH, other thread's load must have failed | |
| 529 super_load_in_progress = false; | |
| 530 } | |
| 531 } | |
| 532 } | |
| 533 return (nh); | |
| 534 } | |
| 535 | |
| 536 | |
| 537 klassOop SystemDictionary::resolve_instance_class_or_null(symbolHandle class_name, Handle class_loader, Handle protection_domain, TRAPS) { | |
| 538 assert(class_name.not_null() && !FieldType::is_array(class_name()), "invalid class name"); | |
| 539 // First check to see if we should remove wrapping L and ; | |
| 540 symbolHandle name; | |
| 541 if (FieldType::is_obj(class_name())) { | |
| 542 ResourceMark rm(THREAD); | |
| 543 // Ignore wrapping L and ;. | |
| 544 name = oopFactory::new_symbol_handle(class_name()->as_C_string() + 1, class_name()->utf8_length() - 2, CHECK_NULL); | |
| 545 } else { | |
| 546 name = class_name; | |
| 547 } | |
| 548 | |
| 549 // UseNewReflection | |
| 550 // Fix for 4474172; see evaluation for more details | |
| 551 class_loader = Handle(THREAD, java_lang_ClassLoader::non_reflection_class_loader(class_loader())); | |
| 552 | |
| 553 // Do lookup to see if class already exist and the protection domain | |
| 554 // has the right access | |
| 555 unsigned int d_hash = dictionary()->compute_hash(name, class_loader); | |
| 556 int d_index = dictionary()->hash_to_index(d_hash); | |
| 557 klassOop probe = dictionary()->find(d_index, d_hash, name, class_loader, | |
| 558 protection_domain, THREAD); | |
| 559 if (probe != NULL) return probe; | |
| 560 | |
| 561 | |
| 562 // Non-bootstrap class loaders will call out to class loader and | |
| 563 // define via jvm/jni_DefineClass which will acquire the | |
| 564 // class loader object lock to protect against multiple threads | |
| 565 // defining the class in parallel by accident. | |
| 566 // This lock must be acquired here so the waiter will find | |
| 567 // any successful result in the SystemDictionary and not attempt | |
| 568 // the define | |
| 569 // Classloaders that support parallelism, e.g. bootstrap classloader, | |
| 570 // or all classloaders with UnsyncloadClass do not acquire lock here | |
| 571 bool DoObjectLock = true; | |
| 572 if (UnsyncloadClass || (class_loader.is_null())) { | |
| 573 DoObjectLock = false; | |
| 574 } | |
| 575 | |
| 576 unsigned int p_hash = placeholders()->compute_hash(name, class_loader); | |
| 577 int p_index = placeholders()->hash_to_index(p_hash); | |
| 578 | |
| 579 // Class is not in SystemDictionary so we have to do loading. | |
| 580 // Make sure we are synchronized on the class loader before we proceed | |
| 581 Handle lockObject = compute_loader_lock_object(class_loader, THREAD); | |
| 582 check_loader_lock_contention(lockObject, THREAD); | |
| 583 ObjectLocker ol(lockObject, THREAD, DoObjectLock); | |
| 584 | |
| 585 // Check again (after locking) if class already exist in SystemDictionary | |
| 586 bool class_has_been_loaded = false; | |
| 587 bool super_load_in_progress = false; | |
| 588 bool havesupername = false; | |
| 589 instanceKlassHandle k; | |
| 590 PlaceholderEntry* placeholder; | |
| 591 symbolHandle superclassname; | |
| 592 | |
| 593 { | |
| 594 MutexLocker mu(SystemDictionary_lock, THREAD); | |
| 595 klassOop check = find_class(d_index, d_hash, name, class_loader); | |
| 596 if (check != NULL) { | |
| 597 // Klass is already loaded, so just return it | |
| 598 class_has_been_loaded = true; | |
| 599 k = instanceKlassHandle(THREAD, check); | |
| 600 } else { | |
| 601 placeholder = placeholders()->get_entry(p_index, p_hash, name, class_loader); | |
| 602 if (placeholder && placeholder->super_load_in_progress()) { | |
| 603 super_load_in_progress = true; | |
| 604 if (placeholder->havesupername() == true) { | |
| 605 superclassname = symbolHandle(THREAD, placeholder->supername()); | |
| 606 havesupername = true; | |
| 607 } | |
| 608 } | |
| 609 } | |
| 610 } | |
| 611 | |
| 612 // If the class in is in the placeholder table, class loading is in progress | |
| 613 if (super_load_in_progress && havesupername==true) { | |
| 614 k = SystemDictionary::handle_parallel_super_load(name, superclassname, | |
| 615 class_loader, protection_domain, lockObject, THREAD); | |
| 616 if (HAS_PENDING_EXCEPTION) { | |
| 617 return NULL; | |
| 618 } | |
| 619 if (!k.is_null()) { | |
| 620 class_has_been_loaded = true; | |
| 621 } | |
| 622 } | |
| 623 | |
| 624 if (!class_has_been_loaded) { | |
| 625 | |
| 626 // add placeholder entry to record loading instance class | |
| 627 // Five cases: | |
| 628 // All cases need to prevent modifying bootclasssearchpath | |
| 629 // in parallel with a classload of same classname | |
| 630 // case 1. traditional classloaders that rely on the classloader object lock | |
| 631 // - no other need for LOAD_INSTANCE | |
| 632 // case 2. traditional classloaders that break the classloader object lock | |
| 633 // as a deadlock workaround. Detection of this case requires that | |
| 634 // this check is done while holding the classloader object lock, | |
| 635 // and that lock is still held when calling classloader's loadClass. | |
| 636 // For these classloaders, we ensure that the first requestor | |
| 637 // completes the load and other requestors wait for completion. | |
| 638 // case 3. UnsyncloadClass - don't use objectLocker | |
| 639 // With this flag, we allow parallel classloading of a | |
| 640 // class/classloader pair | |
| 641 // case4. Bootstrap classloader - don't own objectLocker | |
| 642 // This classloader supports parallelism at the classloader level, | |
| 643 // but only allows a single load of a class/classloader pair. | |
| 644 // No performance benefit and no deadlock issues. | |
| 645 // case 5. Future: parallel user level classloaders - without objectLocker | |
| 646 symbolHandle nullsymbolHandle; | |
| 647 bool throw_circularity_error = false; | |
| 648 { | |
| 649 MutexLocker mu(SystemDictionary_lock, THREAD); | |
| 650 if (!UnsyncloadClass) { | |
| 651 PlaceholderEntry* oldprobe = placeholders()->get_entry(p_index, p_hash, name, class_loader); | |
| 652 if (oldprobe) { | |
| 653 // only need check_seen_thread once, not on each loop | |
| 654 // 6341374 java/lang/Instrument with -Xcomp | |
| 655 if (oldprobe->check_seen_thread(THREAD, PlaceholderTable::LOAD_INSTANCE)) { | |
| 656 throw_circularity_error = true; | |
| 657 } else { | |
| 658 // case 1: traditional: should never see load_in_progress. | |
| 659 while (!class_has_been_loaded && oldprobe && oldprobe->instance_load_in_progress()) { | |
| 660 | |
| 661 // case 4: bootstrap classloader: prevent futile classloading, | |
| 662 // wait on first requestor | |
| 663 if (class_loader.is_null()) { | |
| 664 SystemDictionary_lock->wait(); | |
| 665 } else { | |
| 666 // case 2: traditional with broken classloader lock. wait on first | |
| 667 // requestor. | |
| 668 double_lock_wait(lockObject, THREAD); | |
| 669 } | |
| 670 // Check if classloading completed while we were waiting | |
| 671 klassOop check = find_class(d_index, d_hash, name, class_loader); | |
| 672 if (check != NULL) { | |
| 673 // Klass is already loaded, so just return it | |
| 674 k = instanceKlassHandle(THREAD, check); | |
| 675 class_has_been_loaded = true; | |
| 676 } | |
| 677 // check if other thread failed to load and cleaned up | |
| 678 oldprobe = placeholders()->get_entry(p_index, p_hash, name, class_loader); | |
| 679 } | |
| 680 } | |
| 681 } | |
| 682 } | |
| 683 // All cases: add LOAD_INSTANCE | |
| 684 // case 3: UnsyncloadClass: allow competing threads to try | |
| 685 // LOAD_INSTANCE in parallel | |
| 686 // add placeholder entry even if error - callers will remove on error | |
| 687 if (!class_has_been_loaded) { | |
| 688 PlaceholderEntry* newprobe = placeholders()->find_and_add(p_index, p_hash, name, class_loader, PlaceholderTable::LOAD_INSTANCE, nullsymbolHandle, THREAD); | |
| 689 if (throw_circularity_error) { | |
| 690 newprobe->remove_seen_thread(THREAD, PlaceholderTable::LOAD_INSTANCE); | |
| 691 } | |
| 692 // For class loaders that do not acquire the classloader object lock, | |
| 693 // if they did not catch another thread holding LOAD_INSTANCE, | |
| 694 // need a check analogous to the acquire ObjectLocker/find_class | |
| 695 // i.e. now that we hold the LOAD_INSTANCE token on loading this class/CL | |
| 696 // one final check if the load has already completed | |
| 697 klassOop check = find_class(d_index, d_hash, name, class_loader); | |
| 698 if (check != NULL) { | |
| 699 // Klass is already loaded, so just return it | |
| 700 k = instanceKlassHandle(THREAD, check); | |
| 701 class_has_been_loaded = true; | |
| 702 newprobe->remove_seen_thread(THREAD, PlaceholderTable::LOAD_INSTANCE); | |
| 703 } | |
| 704 } | |
| 705 } | |
| 706 // must throw error outside of owning lock | |
| 707 if (throw_circularity_error) { | |
| 708 ResourceMark rm(THREAD); | |
| 709 THROW_MSG_0(vmSymbols::java_lang_ClassCircularityError(), name->as_C_string()); | |
| 710 } | |
| 711 | |
| 712 if (!class_has_been_loaded) { | |
| 713 | |
| 714 // Do actual loading | |
| 715 k = load_instance_class(name, class_loader, THREAD); | |
| 716 | |
| 717 // In custom class loaders, the usual findClass calls | |
| 718 // findLoadedClass, which directly searches the SystemDictionary, then | |
| 719 // defineClass. If these are not atomic with respect to other threads, | |
| 720 // the findLoadedClass can fail, but the defineClass can get a | |
| 721 // LinkageError:: duplicate class definition. | |
| 722 // If they got a linkageError, check if a parallel class load succeeded. | |
| 723 // If it did, then for bytecode resolution the specification requires | |
| 724 // that we return the same result we did for the other thread, i.e. the | |
| 725 // successfully loaded instanceKlass | |
| 726 // Note: Class can not be unloaded as long as any classloader refs exist | |
| 727 // Should not get here for classloaders that support parallelism | |
| 728 // with the new cleaner mechanism, e.g. bootstrap classloader | |
| 729 if (UnsyncloadClass || (class_loader.is_null())) { | |
| 730 if (k.is_null() && HAS_PENDING_EXCEPTION | |
| 731 && PENDING_EXCEPTION->is_a(SystemDictionary::linkageError_klass())) { | |
| 732 MutexLocker mu(SystemDictionary_lock, THREAD); | |
| 733 klassOop check = find_class(d_index, d_hash, name, class_loader); | |
| 734 if (check != NULL) { | |
| 735 // Klass is already loaded, so just use it | |
| 736 k = instanceKlassHandle(THREAD, check); | |
| 737 CLEAR_PENDING_EXCEPTION; | |
| 738 guarantee((!class_loader.is_null()), "dup definition for bootstrap loader?"); | |
| 739 } | |
| 740 } | |
| 741 } | |
| 742 | |
| 743 // clean up placeholder entries for success or error | |
| 744 // This cleans up LOAD_INSTANCE entries | |
| 745 // It also cleans up LOAD_SUPER entries on errors from | |
| 746 // calling load_instance_class | |
| 747 { | |
| 748 MutexLocker mu(SystemDictionary_lock, THREAD); | |
| 749 PlaceholderEntry* probe = placeholders()->get_entry(p_index, p_hash, name, class_loader); | |
| 750 if (probe != NULL) { | |
| 751 probe->remove_seen_thread(THREAD, PlaceholderTable::LOAD_INSTANCE); | |
| 752 placeholders()->find_and_remove(p_index, p_hash, name, class_loader, THREAD); | |
| 753 SystemDictionary_lock->notify_all(); | |
| 754 } | |
| 755 } | |
| 756 | |
| 757 // If everything was OK (no exceptions, no null return value), and | |
| 758 // class_loader is NOT the defining loader, do a little more bookkeeping. | |
| 759 if (!HAS_PENDING_EXCEPTION && !k.is_null() && | |
| 760 k->class_loader() != class_loader()) { | |
| 761 | |
| 762 check_constraints(d_index, d_hash, k, class_loader, false, THREAD); | |
| 763 | |
| 764 // Need to check for a PENDING_EXCEPTION again; check_constraints | |
| 765 // can throw and doesn't use the CHECK macro. | |
| 766 if (!HAS_PENDING_EXCEPTION) { | |
| 767 { // Grabbing the Compile_lock prevents systemDictionary updates | |
| 768 // during compilations. | |
| 769 MutexLocker mu(Compile_lock, THREAD); | |
| 770 update_dictionary(d_index, d_hash, p_index, p_hash, | |
| 771 k, class_loader, THREAD); | |
| 772 } | |
| 773 if (JvmtiExport::should_post_class_load()) { | |
| 774 Thread *thread = THREAD; | |
| 775 assert(thread->is_Java_thread(), "thread->is_Java_thread()"); | |
| 776 JvmtiExport::post_class_load((JavaThread *) thread, k()); | |
| 777 } | |
| 778 } | |
| 779 } | |
| 780 if (HAS_PENDING_EXCEPTION || k.is_null()) { | |
| 781 // On error, clean up placeholders | |
| 782 { | |
| 783 MutexLocker mu(SystemDictionary_lock, THREAD); | |
| 784 placeholders()->find_and_remove(p_index, p_hash, name, class_loader, THREAD); | |
| 785 SystemDictionary_lock->notify_all(); | |
| 786 } | |
| 787 return NULL; | |
| 788 } | |
| 789 } | |
| 790 } | |
| 791 | |
| 792 #ifdef ASSERT | |
| 793 { | |
| 794 Handle loader (THREAD, k->class_loader()); | |
| 795 MutexLocker mu(SystemDictionary_lock, THREAD); | |
| 796 oop kk = find_class_or_placeholder(name, loader); | |
| 797 assert(kk == k(), "should be present in dictionary"); | |
| 798 } | |
| 799 #endif | |
| 800 | |
| 801 // return if the protection domain in NULL | |
| 802 if (protection_domain() == NULL) return k(); | |
| 803 | |
| 804 // Check the protection domain has the right access | |
| 805 { | |
| 806 MutexLocker mu(SystemDictionary_lock, THREAD); | |
| 807 // Note that we have an entry, and entries can be deleted only during GC, | |
| 808 // so we cannot allow GC to occur while we're holding this entry. | |
| 809 // We're using a No_Safepoint_Verifier to catch any place where we | |
| 810 // might potentially do a GC at all. | |
| 811 // SystemDictionary::do_unloading() asserts that classes are only | |
| 812 // unloaded at a safepoint. | |
| 813 No_Safepoint_Verifier nosafepoint; | |
| 814 if (dictionary()->is_valid_protection_domain(d_index, d_hash, name, | |
| 815 class_loader, | |
| 816 protection_domain)) { | |
| 817 return k(); | |
| 818 } | |
| 819 } | |
| 820 | |
| 821 // Verify protection domain. If it fails an exception is thrown | |
| 822 validate_protection_domain(k, class_loader, protection_domain, CHECK_(klassOop(NULL))); | |
| 823 | |
| 824 return k(); | |
| 825 } | |
| 826 | |
| 827 | |
| 828 // This routine does not lock the system dictionary. | |
| 829 // | |
| 830 // Since readers don't hold a lock, we must make sure that system | |
| 831 // dictionary entries are only removed at a safepoint (when only one | |
| 832 // thread is running), and are added to in a safe way (all links must | |
| 833 // be updated in an MT-safe manner). | |
| 834 // | |
| 835 // Callers should be aware that an entry could be added just after | |
| 836 // _dictionary->bucket(index) is read here, so the caller will not see | |
| 837 // the new entry. | |
| 838 | |
| 839 klassOop SystemDictionary::find(symbolHandle class_name, | |
| 840 Handle class_loader, | |
| 841 Handle protection_domain, | |
| 842 TRAPS) { | |
| 843 | |
| 844 unsigned int d_hash = dictionary()->compute_hash(class_name, class_loader); | |
| 845 int d_index = dictionary()->hash_to_index(d_hash); | |
| 846 | |
| 847 { | |
| 848 // Note that we have an entry, and entries can be deleted only during GC, | |
| 849 // so we cannot allow GC to occur while we're holding this entry. | |
| 850 // We're using a No_Safepoint_Verifier to catch any place where we | |
| 851 // might potentially do a GC at all. | |
| 852 // SystemDictionary::do_unloading() asserts that classes are only | |
| 853 // unloaded at a safepoint. | |
| 854 No_Safepoint_Verifier nosafepoint; | |
| 855 return dictionary()->find(d_index, d_hash, class_name, class_loader, | |
| 856 protection_domain, THREAD); | |
| 857 } | |
| 858 } | |
| 859 | |
| 860 | |
| 861 // Look for a loaded instance or array klass by name. Do not do any loading. | |
| 862 // return NULL in case of error. | |
| 863 klassOop SystemDictionary::find_instance_or_array_klass(symbolHandle class_name, | |
| 864 Handle class_loader, | |
| 865 Handle protection_domain, | |
| 866 TRAPS) { | |
| 867 klassOop k = NULL; | |
| 868 assert(class_name() != NULL, "class name must be non NULL"); | |
|
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869 |
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870 // Try to get one of the well-known klasses. |
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871 if (LinkWellKnownClasses) { |
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872 k = find_well_known_klass(class_name()); |
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873 if (k != NULL) { |
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874 return k; |
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875 } |
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876 } |
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877 |
| 0 | 878 if (FieldType::is_array(class_name())) { |
| 879 // The name refers to an array. Parse the name. | |
| 880 jint dimension; | |
| 881 symbolOop object_key; | |
| 882 | |
| 883 // dimension and object_key are assigned as a side-effect of this call | |
| 884 BasicType t = FieldType::get_array_info(class_name(), &dimension, | |
| 885 &object_key, CHECK_(NULL)); | |
| 886 if (t != T_OBJECT) { | |
| 887 k = Universe::typeArrayKlassObj(t); | |
| 888 } else { | |
| 889 symbolHandle h_key(THREAD, object_key); | |
| 890 k = SystemDictionary::find(h_key, class_loader, protection_domain, THREAD); | |
| 891 } | |
| 892 if (k != NULL) { | |
| 893 k = Klass::cast(k)->array_klass_or_null(dimension); | |
| 894 } | |
| 895 } else { | |
| 896 k = find(class_name, class_loader, protection_domain, THREAD); | |
| 897 } | |
| 898 return k; | |
| 899 } | |
| 900 | |
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901 // Quick range check for names of well-known classes: |
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902 static symbolOop wk_klass_name_limits[2] = {NULL, NULL}; |
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903 |
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904 #ifndef PRODUCT |
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905 static int find_wkk_calls, find_wkk_probes, find_wkk_wins; |
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906 // counts for "hello world": 3983, 1616, 1075 |
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907 // => 60% hit after limit guard, 25% total win rate |
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908 #endif |
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909 |
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910 klassOop SystemDictionary::find_well_known_klass(symbolOop class_name) { |
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911 // A bounds-check on class_name will quickly get a negative result. |
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912 NOT_PRODUCT(find_wkk_calls++); |
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913 if (class_name >= wk_klass_name_limits[0] && |
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914 class_name <= wk_klass_name_limits[1]) { |
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915 NOT_PRODUCT(find_wkk_probes++); |
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916 vmSymbols::SID sid = vmSymbols::find_sid(class_name); |
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917 if (sid != vmSymbols::NO_SID) { |
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918 klassOop k = NULL; |
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919 switch (sid) { |
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920 #define WK_KLASS_CASE(name, symbol, ignore_option) \ |
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921 case vmSymbols::VM_SYMBOL_ENUM_NAME(symbol): \ |
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922 k = WK_KLASS(name); break; |
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923 WK_KLASSES_DO(WK_KLASS_CASE) |
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924 #undef WK_KLASS_CASE |
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925 } |
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926 NOT_PRODUCT(if (k != NULL) find_wkk_wins++); |
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927 return k; |
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928 } |
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929 } |
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930 return NULL; |
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931 } |
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932 |
| 0 | 933 // Note: this method is much like resolve_from_stream, but |
| 934 // updates no supplemental data structures. | |
| 935 // TODO consolidate the two methods with a helper routine? | |
| 936 klassOop SystemDictionary::parse_stream(symbolHandle class_name, | |
| 937 Handle class_loader, | |
| 938 Handle protection_domain, | |
| 939 ClassFileStream* st, | |
| 940 TRAPS) { | |
| 941 symbolHandle parsed_name; | |
| 942 | |
| 943 // Parse the stream. Note that we do this even though this klass might | |
| 944 // already be present in the SystemDictionary, otherwise we would not | |
| 945 // throw potential ClassFormatErrors. | |
| 946 // | |
| 947 // Note: "name" is updated. | |
| 948 // Further note: a placeholder will be added for this class when | |
| 949 // super classes are loaded (resolve_super_or_fail). We expect this | |
| 950 // to be called for all classes but java.lang.Object; and we preload | |
| 951 // java.lang.Object through resolve_or_fail, not this path. | |
| 952 | |
| 953 instanceKlassHandle k = ClassFileParser(st).parseClassFile(class_name, | |
| 954 class_loader, | |
| 955 protection_domain, | |
| 956 parsed_name, | |
| 957 THREAD); | |
| 958 | |
| 959 | |
| 960 // We don't redefine the class, so we just need to clean up whether there | |
| 961 // was an error or not (don't want to modify any system dictionary | |
| 962 // data structures). | |
| 963 // Parsed name could be null if we threw an error before we got far | |
| 964 // enough along to parse it -- in that case, there is nothing to clean up. | |
| 965 if (!parsed_name.is_null()) { | |
| 966 unsigned int p_hash = placeholders()->compute_hash(parsed_name, | |
| 967 class_loader); | |
| 968 int p_index = placeholders()->hash_to_index(p_hash); | |
| 969 { | |
| 970 MutexLocker mu(SystemDictionary_lock, THREAD); | |
| 971 placeholders()->find_and_remove(p_index, p_hash, parsed_name, class_loader, THREAD); | |
| 972 SystemDictionary_lock->notify_all(); | |
| 973 } | |
| 974 } | |
| 975 | |
| 976 return k(); | |
| 977 } | |
| 978 | |
| 979 // Add a klass to the system from a stream (called by jni_DefineClass and | |
| 980 // JVM_DefineClass). | |
| 981 // Note: class_name can be NULL. In that case we do not know the name of | |
| 982 // the class until we have parsed the stream. | |
| 983 | |
| 984 klassOop SystemDictionary::resolve_from_stream(symbolHandle class_name, | |
| 985 Handle class_loader, | |
| 986 Handle protection_domain, | |
| 987 ClassFileStream* st, | |
| 988 TRAPS) { | |
| 989 | |
| 990 // Make sure we are synchronized on the class loader before we initiate | |
| 991 // loading. | |
| 992 Handle lockObject = compute_loader_lock_object(class_loader, THREAD); | |
| 993 check_loader_lock_contention(lockObject, THREAD); | |
| 994 ObjectLocker ol(lockObject, THREAD); | |
| 995 | |
| 996 symbolHandle parsed_name; | |
| 997 | |
| 998 // Parse the stream. Note that we do this even though this klass might | |
| 999 // already be present in the SystemDictionary, otherwise we would not | |
| 1000 // throw potential ClassFormatErrors. | |
| 1001 // | |
| 1002 // Note: "name" is updated. | |
| 1003 // Further note: a placeholder will be added for this class when | |
| 1004 // super classes are loaded (resolve_super_or_fail). We expect this | |
| 1005 // to be called for all classes but java.lang.Object; and we preload | |
| 1006 // java.lang.Object through resolve_or_fail, not this path. | |
| 1007 | |
| 1008 instanceKlassHandle k = ClassFileParser(st).parseClassFile(class_name, | |
| 1009 class_loader, | |
| 1010 protection_domain, | |
| 1011 parsed_name, | |
| 1012 THREAD); | |
| 1013 | |
| 1014 const char* pkg = "java/"; | |
| 1015 if (!HAS_PENDING_EXCEPTION && | |
| 1016 !class_loader.is_null() && | |
| 1017 !parsed_name.is_null() && | |
| 1018 !strncmp((const char*)parsed_name->bytes(), pkg, strlen(pkg))) { | |
| 1019 // It is illegal to define classes in the "java." package from | |
| 1020 // JVM_DefineClass or jni_DefineClass unless you're the bootclassloader | |
| 1021 ResourceMark rm(THREAD); | |
| 1022 char* name = parsed_name->as_C_string(); | |
| 1023 char* index = strrchr(name, '/'); | |
| 1024 *index = '\0'; // chop to just the package name | |
| 1025 while ((index = strchr(name, '/')) != NULL) { | |
| 1026 *index = '.'; // replace '/' with '.' in package name | |
| 1027 } | |
| 1028 const char* fmt = "Prohibited package name: %s"; | |
| 1029 size_t len = strlen(fmt) + strlen(name); | |
| 1030 char* message = NEW_RESOURCE_ARRAY(char, len); | |
| 1031 jio_snprintf(message, len, fmt, name); | |
| 1032 Exceptions::_throw_msg(THREAD_AND_LOCATION, | |
| 1033 vmSymbols::java_lang_SecurityException(), message); | |
| 1034 } | |
| 1035 | |
| 1036 if (!HAS_PENDING_EXCEPTION) { | |
| 1037 assert(!parsed_name.is_null(), "Sanity"); | |
| 1038 assert(class_name.is_null() || class_name() == parsed_name(), | |
| 1039 "name mismatch"); | |
| 1040 // Verification prevents us from creating names with dots in them, this | |
| 1041 // asserts that that's the case. | |
| 1042 assert(is_internal_format(parsed_name), | |
| 1043 "external class name format used internally"); | |
| 1044 | |
| 1045 // Add class just loaded | |
| 1046 define_instance_class(k, THREAD); | |
| 1047 } | |
| 1048 | |
| 1049 // If parsing the class file or define_instance_class failed, we | |
| 1050 // need to remove the placeholder added on our behalf. But we | |
| 1051 // must make sure parsed_name is valid first (it won't be if we had | |
| 1052 // a format error before the class was parsed far enough to | |
| 1053 // find the name). | |
| 1054 if (HAS_PENDING_EXCEPTION && !parsed_name.is_null()) { | |
| 1055 unsigned int p_hash = placeholders()->compute_hash(parsed_name, | |
| 1056 class_loader); | |
| 1057 int p_index = placeholders()->hash_to_index(p_hash); | |
| 1058 { | |
| 1059 MutexLocker mu(SystemDictionary_lock, THREAD); | |
| 1060 placeholders()->find_and_remove(p_index, p_hash, parsed_name, class_loader, THREAD); | |
| 1061 SystemDictionary_lock->notify_all(); | |
| 1062 } | |
| 1063 return NULL; | |
| 1064 } | |
| 1065 | |
| 1066 // Make sure that we didn't leave a place holder in the | |
| 1067 // SystemDictionary; this is only done on success | |
| 1068 debug_only( { | |
| 1069 if (!HAS_PENDING_EXCEPTION) { | |
| 1070 assert(!parsed_name.is_null(), "parsed_name is still null?"); | |
| 1071 symbolHandle h_name (THREAD, k->name()); | |
| 1072 Handle h_loader (THREAD, k->class_loader()); | |
| 1073 | |
| 1074 MutexLocker mu(SystemDictionary_lock, THREAD); | |
| 1075 | |
| 1076 oop check = find_class_or_placeholder(parsed_name, class_loader); | |
| 1077 assert(check == k(), "should be present in the dictionary"); | |
| 1078 | |
| 1079 oop check2 = find_class_or_placeholder(h_name, h_loader); | |
| 1080 assert(check == check2, "name inconsistancy in SystemDictionary"); | |
| 1081 } | |
| 1082 } ); | |
| 1083 | |
| 1084 return k(); | |
| 1085 } | |
| 1086 | |
| 1087 | |
| 1088 void SystemDictionary::set_shared_dictionary(HashtableBucket* t, int length, | |
| 1089 int number_of_entries) { | |
| 1090 assert(length == _nof_buckets * sizeof(HashtableBucket), | |
| 1091 "bad shared dictionary size."); | |
| 1092 _shared_dictionary = new Dictionary(_nof_buckets, t, number_of_entries); | |
| 1093 } | |
| 1094 | |
| 1095 | |
| 1096 // If there is a shared dictionary, then find the entry for the | |
| 1097 // given shared system class, if any. | |
| 1098 | |
| 1099 klassOop SystemDictionary::find_shared_class(symbolHandle class_name) { | |
| 1100 if (shared_dictionary() != NULL) { | |
| 1101 unsigned int d_hash = dictionary()->compute_hash(class_name, Handle()); | |
| 1102 int d_index = dictionary()->hash_to_index(d_hash); | |
| 1103 return shared_dictionary()->find_shared_class(d_index, d_hash, class_name); | |
| 1104 } else { | |
| 1105 return NULL; | |
| 1106 } | |
| 1107 } | |
| 1108 | |
| 1109 | |
| 1110 // Load a class from the shared spaces (found through the shared system | |
| 1111 // dictionary). Force the superclass and all interfaces to be loaded. | |
| 1112 // Update the class definition to include sibling classes and no | |
| 1113 // subclasses (yet). [Classes in the shared space are not part of the | |
| 1114 // object hierarchy until loaded.] | |
| 1115 | |
| 1116 instanceKlassHandle SystemDictionary::load_shared_class( | |
| 1117 symbolHandle class_name, Handle class_loader, TRAPS) { | |
| 1118 instanceKlassHandle ik (THREAD, find_shared_class(class_name)); | |
| 1119 return load_shared_class(ik, class_loader, THREAD); | |
| 1120 } | |
| 1121 | |
| 1122 // Note well! Changes to this method may affect oop access order | |
| 1123 // in the shared archive. Please take care to not make changes that | |
| 1124 // adversely affect cold start time by changing the oop access order | |
| 1125 // that is specified in dump.cpp MarkAndMoveOrderedReadOnly and | |
| 1126 // MarkAndMoveOrderedReadWrite closures. | |
| 1127 instanceKlassHandle SystemDictionary::load_shared_class( | |
| 1128 instanceKlassHandle ik, Handle class_loader, TRAPS) { | |
| 1129 assert(class_loader.is_null(), "non-null classloader for shared class?"); | |
| 1130 if (ik.not_null()) { | |
| 1131 instanceKlassHandle nh = instanceKlassHandle(); // null Handle | |
| 1132 symbolHandle class_name(THREAD, ik->name()); | |
| 1133 | |
| 1134 // Found the class, now load the superclass and interfaces. If they | |
| 1135 // are shared, add them to the main system dictionary and reset | |
| 1136 // their hierarchy references (supers, subs, and interfaces). | |
| 1137 | |
| 1138 if (ik->super() != NULL) { | |
| 1139 symbolHandle cn(THREAD, ik->super()->klass_part()->name()); | |
| 1140 resolve_super_or_fail(class_name, cn, | |
| 1141 class_loader, Handle(), true, CHECK_(nh)); | |
| 1142 } | |
| 1143 | |
| 1144 objArrayHandle interfaces (THREAD, ik->local_interfaces()); | |
| 1145 int num_interfaces = interfaces->length(); | |
| 1146 for (int index = 0; index < num_interfaces; index++) { | |
| 1147 klassOop k = klassOop(interfaces->obj_at(index)); | |
| 1148 | |
| 1149 // Note: can not use instanceKlass::cast here because | |
| 1150 // interfaces' instanceKlass's C++ vtbls haven't been | |
| 1151 // reinitialized yet (they will be once the interface classes | |
| 1152 // are loaded) | |
| 1153 symbolHandle name (THREAD, k->klass_part()->name()); | |
| 1154 resolve_super_or_fail(class_name, name, class_loader, Handle(), false, CHECK_(nh)); | |
| 1155 } | |
| 1156 | |
| 1157 // Adjust methods to recover missing data. They need addresses for | |
| 1158 // interpreter entry points and their default native method address | |
| 1159 // must be reset. | |
| 1160 | |
| 1161 // Updating methods must be done under a lock so multiple | |
| 1162 // threads don't update these in parallel | |
| 1163 // Shared classes are all currently loaded by the bootstrap | |
| 1164 // classloader, so this will never cause a deadlock on | |
| 1165 // a custom class loader lock. | |
| 1166 | |
| 1167 { | |
| 1168 Handle lockObject = compute_loader_lock_object(class_loader, THREAD); | |
| 1169 check_loader_lock_contention(lockObject, THREAD); | |
| 1170 ObjectLocker ol(lockObject, THREAD, true); | |
| 1171 | |
| 1172 objArrayHandle methods (THREAD, ik->methods()); | |
| 1173 int num_methods = methods->length(); | |
| 1174 for (int index2 = 0; index2 < num_methods; ++index2) { | |
| 1175 methodHandle m(THREAD, methodOop(methods->obj_at(index2))); | |
| 1176 m()->link_method(m, CHECK_(nh)); | |
| 1177 } | |
| 1178 } | |
| 1179 | |
| 1180 if (TraceClassLoading) { | |
| 1181 ResourceMark rm; | |
| 1182 tty->print("[Loaded %s", ik->external_name()); | |
| 1183 tty->print(" from shared objects file"); | |
| 1184 tty->print_cr("]"); | |
| 1185 } | |
| 1186 // notify a class loaded from shared object | |
| 1187 ClassLoadingService::notify_class_loaded(instanceKlass::cast(ik()), | |
| 1188 true /* shared class */); | |
| 1189 } | |
| 1190 return ik; | |
| 1191 } | |
| 1192 | |
| 1193 #ifdef KERNEL | |
| 1194 // Some classes on the bootstrap class path haven't been installed on the | |
| 1195 // system yet. Call the DownloadManager method to make them appear in the | |
| 1196 // bootstrap class path and try again to load the named class. | |
| 1197 // Note that with delegation class loaders all classes in another loader will | |
| 1198 // first try to call this so it'd better be fast!! | |
| 1199 static instanceKlassHandle download_and_retry_class_load( | |
| 1200 symbolHandle class_name, | |
| 1201 TRAPS) { | |
| 1202 | |
| 1203 klassOop dlm = SystemDictionary::sun_jkernel_DownloadManager_klass(); | |
| 1204 instanceKlassHandle nk; | |
| 1205 | |
| 1206 // If download manager class isn't loaded just return. | |
| 1207 if (dlm == NULL) return nk; | |
| 1208 | |
| 1209 { HandleMark hm(THREAD); | |
| 1210 ResourceMark rm(THREAD); | |
| 1211 Handle s = java_lang_String::create_from_symbol(class_name, CHECK_(nk)); | |
| 1212 Handle class_string = java_lang_String::externalize_classname(s, CHECK_(nk)); | |
| 1213 | |
| 1214 // return value | |
| 1215 JavaValue result(T_OBJECT); | |
| 1216 | |
| 1217 // Call the DownloadManager. We assume that it has a lock because | |
| 1218 // multiple classes could be not found and downloaded at the same time. | |
| 1219 // class sun.misc.DownloadManager; | |
| 1220 // public static String getBootClassPathEntryForClass(String className); | |
| 1221 JavaCalls::call_static(&result, | |
| 1222 KlassHandle(THREAD, dlm), | |
| 1223 vmSymbolHandles::getBootClassPathEntryForClass_name(), | |
| 1224 vmSymbolHandles::string_string_signature(), | |
| 1225 class_string, | |
| 1226 CHECK_(nk)); | |
| 1227 | |
| 1228 // Get result.string and add to bootclasspath | |
| 1229 assert(result.get_type() == T_OBJECT, "just checking"); | |
| 1230 oop obj = (oop) result.get_jobject(); | |
| 1231 if (obj == NULL) { return nk; } | |
| 1232 | |
|
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1233 Handle h_obj(THREAD, obj); |
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1234 char* new_class_name = java_lang_String::as_platform_dependent_str(h_obj, |
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1235 CHECK_(nk)); |
| 0 | 1236 |
| 1237 // lock the loader | |
| 1238 // we use this lock because JVMTI does. | |
| 1239 Handle loader_lock(THREAD, SystemDictionary::system_loader_lock()); | |
| 1240 | |
| 1241 ObjectLocker ol(loader_lock, THREAD); | |
| 1242 // add the file to the bootclasspath | |
| 1243 ClassLoader::update_class_path_entry_list(new_class_name, true); | |
| 1244 } // end HandleMark | |
| 1245 | |
| 1246 if (TraceClassLoading) { | |
| 1247 ClassLoader::print_bootclasspath(); | |
| 1248 } | |
| 1249 return ClassLoader::load_classfile(class_name, CHECK_(nk)); | |
| 1250 } | |
| 1251 #endif // KERNEL | |
| 1252 | |
| 1253 | |
| 1254 instanceKlassHandle SystemDictionary::load_instance_class(symbolHandle class_name, Handle class_loader, TRAPS) { | |
| 1255 instanceKlassHandle nh = instanceKlassHandle(); // null Handle | |
| 1256 if (class_loader.is_null()) { | |
| 1257 // Search the shared system dictionary for classes preloaded into the | |
| 1258 // shared spaces. | |
| 1259 instanceKlassHandle k; | |
| 1260 k = load_shared_class(class_name, class_loader, THREAD); | |
| 1261 | |
| 1262 if (k.is_null()) { | |
| 1263 // Use VM class loader | |
| 1264 k = ClassLoader::load_classfile(class_name, CHECK_(nh)); | |
| 1265 } | |
| 1266 | |
| 1267 #ifdef KERNEL | |
| 1268 // If the VM class loader has failed to load the class, call the | |
| 1269 // DownloadManager class to make it magically appear on the classpath | |
| 1270 // and try again. This is only configured with the Kernel VM. | |
| 1271 if (k.is_null()) { | |
| 1272 k = download_and_retry_class_load(class_name, CHECK_(nh)); | |
| 1273 } | |
| 1274 #endif // KERNEL | |
| 1275 | |
| 1276 // find_or_define_instance_class may return a different k | |
| 1277 if (!k.is_null()) { | |
| 1278 k = find_or_define_instance_class(class_name, class_loader, k, CHECK_(nh)); | |
| 1279 } | |
| 1280 return k; | |
| 1281 } else { | |
| 1282 // Use user specified class loader to load class. Call loadClass operation on class_loader. | |
| 1283 ResourceMark rm(THREAD); | |
| 1284 | |
| 1285 Handle s = java_lang_String::create_from_symbol(class_name, CHECK_(nh)); | |
| 1286 // Translate to external class name format, i.e., convert '/' chars to '.' | |
| 1287 Handle string = java_lang_String::externalize_classname(s, CHECK_(nh)); | |
| 1288 | |
| 1289 JavaValue result(T_OBJECT); | |
| 1290 | |
| 1291 KlassHandle spec_klass (THREAD, SystemDictionary::classloader_klass()); | |
| 1292 | |
| 1293 // UnsyncloadClass option means don't synchronize loadClass() calls. | |
| 1294 // loadClassInternal() is synchronized and public loadClass(String) is not. | |
| 1295 // This flag is for diagnostic purposes only. It is risky to call | |
| 1296 // custom class loaders without synchronization. | |
| 1297 // WARNING If a custom class loader does NOT synchronizer findClass, or callers of | |
| 1298 // findClass, this flag risks unexpected timing bugs in the field. | |
| 1299 // Do NOT assume this will be supported in future releases. | |
| 1300 if (!UnsyncloadClass && has_loadClassInternal()) { | |
| 1301 JavaCalls::call_special(&result, | |
| 1302 class_loader, | |
| 1303 spec_klass, | |
| 1304 vmSymbolHandles::loadClassInternal_name(), | |
| 1305 vmSymbolHandles::string_class_signature(), | |
| 1306 string, | |
| 1307 CHECK_(nh)); | |
| 1308 } else { | |
| 1309 JavaCalls::call_virtual(&result, | |
| 1310 class_loader, | |
| 1311 spec_klass, | |
| 1312 vmSymbolHandles::loadClass_name(), | |
| 1313 vmSymbolHandles::string_class_signature(), | |
| 1314 string, | |
| 1315 CHECK_(nh)); | |
| 1316 } | |
| 1317 | |
| 1318 assert(result.get_type() == T_OBJECT, "just checking"); | |
| 1319 oop obj = (oop) result.get_jobject(); | |
| 1320 | |
| 1321 // Primitive classes return null since forName() can not be | |
| 1322 // used to obtain any of the Class objects representing primitives or void | |
| 1323 if ((obj != NULL) && !(java_lang_Class::is_primitive(obj))) { | |
| 1324 instanceKlassHandle k = | |
| 1325 instanceKlassHandle(THREAD, java_lang_Class::as_klassOop(obj)); | |
| 1326 // For user defined Java class loaders, check that the name returned is | |
| 1327 // the same as that requested. This check is done for the bootstrap | |
| 1328 // loader when parsing the class file. | |
| 1329 if (class_name() == k->name()) { | |
| 1330 return k; | |
| 1331 } | |
| 1332 } | |
| 1333 // Class is not found or has the wrong name, return NULL | |
| 1334 return nh; | |
| 1335 } | |
| 1336 } | |
| 1337 | |
| 1338 void SystemDictionary::define_instance_class(instanceKlassHandle k, TRAPS) { | |
| 1339 | |
| 1340 Handle class_loader_h(THREAD, k->class_loader()); | |
| 1341 | |
| 1342 // for bootstrap classloader don't acquire lock | |
| 1343 if (!class_loader_h.is_null()) { | |
| 1344 assert(ObjectSynchronizer::current_thread_holds_lock((JavaThread*)THREAD, | |
| 1345 compute_loader_lock_object(class_loader_h, THREAD)), | |
| 1346 "define called without lock"); | |
| 1347 } | |
| 1348 | |
| 1349 | |
| 1350 // Check class-loading constraints. Throw exception if violation is detected. | |
| 1351 // Grabs and releases SystemDictionary_lock | |
| 1352 // The check_constraints/find_class call and update_dictionary sequence | |
| 1353 // must be "atomic" for a specific class/classloader pair so we never | |
| 1354 // define two different instanceKlasses for that class/classloader pair. | |
| 1355 // Existing classloaders will call define_instance_class with the | |
| 1356 // classloader lock held | |
| 1357 // Parallel classloaders will call find_or_define_instance_class | |
| 1358 // which will require a token to perform the define class | |
| 1359 symbolHandle name_h(THREAD, k->name()); | |
| 1360 unsigned int d_hash = dictionary()->compute_hash(name_h, class_loader_h); | |
| 1361 int d_index = dictionary()->hash_to_index(d_hash); | |
| 1362 check_constraints(d_index, d_hash, k, class_loader_h, true, CHECK); | |
| 1363 | |
| 1364 // Register class just loaded with class loader (placed in Vector) | |
| 1365 // Note we do this before updating the dictionary, as this can | |
| 1366 // fail with an OutOfMemoryError (if it does, we will *not* put this | |
| 1367 // class in the dictionary and will not update the class hierarchy). | |
| 1368 if (k->class_loader() != NULL) { | |
| 1369 methodHandle m(THREAD, Universe::loader_addClass_method()); | |
| 1370 JavaValue result(T_VOID); | |
| 1371 JavaCallArguments args(class_loader_h); | |
| 1372 args.push_oop(Handle(THREAD, k->java_mirror())); | |
| 1373 JavaCalls::call(&result, m, &args, CHECK); | |
| 1374 } | |
| 1375 | |
| 1376 // Add the new class. We need recompile lock during update of CHA. | |
| 1377 { | |
| 1378 unsigned int p_hash = placeholders()->compute_hash(name_h, class_loader_h); | |
| 1379 int p_index = placeholders()->hash_to_index(p_hash); | |
| 1380 | |
| 1381 MutexLocker mu_r(Compile_lock, THREAD); | |
| 1382 | |
| 1383 // Add to class hierarchy, initialize vtables, and do possible | |
| 1384 // deoptimizations. | |
| 1385 add_to_hierarchy(k, CHECK); // No exception, but can block | |
| 1386 | |
| 1387 // Add to systemDictionary - so other classes can see it. | |
| 1388 // Grabs and releases SystemDictionary_lock | |
| 1389 update_dictionary(d_index, d_hash, p_index, p_hash, | |
| 1390 k, class_loader_h, THREAD); | |
| 1391 } | |
| 1392 k->eager_initialize(THREAD); | |
| 1393 | |
| 1394 // notify jvmti | |
| 1395 if (JvmtiExport::should_post_class_load()) { | |
| 1396 assert(THREAD->is_Java_thread(), "thread->is_Java_thread()"); | |
| 1397 JvmtiExport::post_class_load((JavaThread *) THREAD, k()); | |
| 1398 | |
| 1399 } | |
| 1400 } | |
| 1401 | |
| 1402 // Support parallel classloading | |
| 1403 // Initial implementation for bootstrap classloader | |
| 1404 // For future: | |
| 1405 // For custom class loaders that support parallel classloading, | |
| 1406 // in case they do not synchronize around | |
| 1407 // FindLoadedClass/DefineClass calls, we check for parallel | |
| 1408 // loading for them, wait if a defineClass is in progress | |
| 1409 // and return the initial requestor's results | |
| 1410 // For better performance, the class loaders should synchronize | |
| 1411 // findClass(), i.e. FindLoadedClass/DefineClass or they | |
| 1412 // potentially waste time reading and parsing the bytestream. | |
| 1413 // Note: VM callers should ensure consistency of k/class_name,class_loader | |
| 1414 instanceKlassHandle SystemDictionary::find_or_define_instance_class(symbolHandle class_name, Handle class_loader, instanceKlassHandle k, TRAPS) { | |
| 1415 | |
| 1416 instanceKlassHandle nh = instanceKlassHandle(); // null Handle | |
| 1417 | |
| 1418 unsigned int d_hash = dictionary()->compute_hash(class_name, class_loader); | |
| 1419 int d_index = dictionary()->hash_to_index(d_hash); | |
| 1420 | |
| 1421 // Hold SD lock around find_class and placeholder creation for DEFINE_CLASS | |
| 1422 unsigned int p_hash = placeholders()->compute_hash(class_name, class_loader); | |
| 1423 int p_index = placeholders()->hash_to_index(p_hash); | |
| 1424 PlaceholderEntry* probe; | |
| 1425 | |
| 1426 { | |
| 1427 MutexLocker mu(SystemDictionary_lock, THREAD); | |
| 1428 // First check if class already defined | |
| 1429 klassOop check = find_class(d_index, d_hash, class_name, class_loader); | |
| 1430 if (check != NULL) { | |
| 1431 return(instanceKlassHandle(THREAD, check)); | |
| 1432 } | |
| 1433 | |
| 1434 // Acquire define token for this class/classloader | |
| 1435 symbolHandle nullsymbolHandle; | |
| 1436 probe = placeholders()->find_and_add(p_index, p_hash, class_name, class_loader, PlaceholderTable::DEFINE_CLASS, nullsymbolHandle, THREAD); | |
| 1437 // Check if another thread defining in parallel | |
| 1438 if (probe->definer() == NULL) { | |
| 1439 // Thread will define the class | |
| 1440 probe->set_definer(THREAD); | |
| 1441 } else { | |
| 1442 // Wait for defining thread to finish and return results | |
| 1443 while (probe->definer() != NULL) { | |
| 1444 SystemDictionary_lock->wait(); | |
| 1445 } | |
| 1446 if (probe->instanceKlass() != NULL) { | |
| 1447 probe->remove_seen_thread(THREAD, PlaceholderTable::DEFINE_CLASS); | |
| 1448 return(instanceKlassHandle(THREAD, probe->instanceKlass())); | |
| 1449 } else { | |
| 1450 // If definer had an error, try again as any new thread would | |
| 1451 probe->set_definer(THREAD); | |
| 1452 #ifdef ASSERT | |
| 1453 klassOop check = find_class(d_index, d_hash, class_name, class_loader); | |
| 1454 assert(check == NULL, "definer missed recording success"); | |
| 1455 #endif | |
| 1456 } | |
| 1457 } | |
| 1458 } | |
| 1459 | |
| 1460 define_instance_class(k, THREAD); | |
| 1461 | |
| 1462 Handle linkage_exception = Handle(); // null handle | |
| 1463 | |
| 1464 // definer must notify any waiting threads | |
| 1465 { | |
| 1466 MutexLocker mu(SystemDictionary_lock, THREAD); | |
| 1467 PlaceholderEntry* probe = placeholders()->get_entry(p_index, p_hash, class_name, class_loader); | |
| 1468 assert(probe != NULL, "DEFINE_CLASS placeholder lost?"); | |
| 1469 if (probe != NULL) { | |
| 1470 if (HAS_PENDING_EXCEPTION) { | |
| 1471 linkage_exception = Handle(THREAD,PENDING_EXCEPTION); | |
| 1472 CLEAR_PENDING_EXCEPTION; | |
| 1473 } else { | |
| 1474 probe->set_instanceKlass(k()); | |
| 1475 } | |
| 1476 probe->set_definer(NULL); | |
| 1477 probe->remove_seen_thread(THREAD, PlaceholderTable::DEFINE_CLASS); | |
| 1478 SystemDictionary_lock->notify_all(); | |
| 1479 } | |
| 1480 } | |
| 1481 | |
| 1482 // Can't throw exception while holding lock due to rank ordering | |
| 1483 if (linkage_exception() != NULL) { | |
| 1484 THROW_OOP_(linkage_exception(), nh); // throws exception and returns | |
| 1485 } | |
| 1486 | |
| 1487 return k; | |
| 1488 } | |
| 1489 | |
| 1490 Handle SystemDictionary::compute_loader_lock_object(Handle class_loader, TRAPS) { | |
| 1491 // If class_loader is NULL we synchronize on _system_loader_lock_obj | |
| 1492 if (class_loader.is_null()) { | |
| 1493 return Handle(THREAD, _system_loader_lock_obj); | |
| 1494 } else { | |
| 1495 return class_loader; | |
| 1496 } | |
| 1497 } | |
| 1498 | |
| 1499 // This method is added to check how often we have to wait to grab loader | |
| 1500 // lock. The results are being recorded in the performance counters defined in | |
| 1501 // ClassLoader::_sync_systemLoaderLockContentionRate and | |
| 1502 // ClassLoader::_sync_nonSystemLoaderLockConteionRate. | |
| 1503 void SystemDictionary::check_loader_lock_contention(Handle loader_lock, TRAPS) { | |
| 1504 if (!UsePerfData) { | |
| 1505 return; | |
| 1506 } | |
| 1507 | |
| 1508 assert(!loader_lock.is_null(), "NULL lock object"); | |
| 1509 | |
| 1510 if (ObjectSynchronizer::query_lock_ownership((JavaThread*)THREAD, loader_lock) | |
| 1511 == ObjectSynchronizer::owner_other) { | |
| 1512 // contention will likely happen, so increment the corresponding | |
| 1513 // contention counter. | |
| 1514 if (loader_lock() == _system_loader_lock_obj) { | |
| 1515 ClassLoader::sync_systemLoaderLockContentionRate()->inc(); | |
| 1516 } else { | |
| 1517 ClassLoader::sync_nonSystemLoaderLockContentionRate()->inc(); | |
| 1518 } | |
| 1519 } | |
| 1520 } | |
| 1521 | |
| 1522 // ---------------------------------------------------------------------------- | |
| 1523 // Lookup | |
| 1524 | |
| 1525 klassOop SystemDictionary::find_class(int index, unsigned int hash, | |
| 1526 symbolHandle class_name, | |
| 1527 Handle class_loader) { | |
| 1528 assert_locked_or_safepoint(SystemDictionary_lock); | |
| 1529 assert (index == dictionary()->index_for(class_name, class_loader), | |
| 1530 "incorrect index?"); | |
| 1531 | |
| 1532 klassOop k = dictionary()->find_class(index, hash, class_name, class_loader); | |
| 1533 return k; | |
| 1534 } | |
| 1535 | |
| 1536 | |
| 1537 // Basic find on classes in the midst of being loaded | |
| 1538 symbolOop SystemDictionary::find_placeholder(int index, unsigned int hash, | |
| 1539 symbolHandle class_name, | |
| 1540 Handle class_loader) { | |
| 1541 assert_locked_or_safepoint(SystemDictionary_lock); | |
| 1542 | |
| 1543 return placeholders()->find_entry(index, hash, class_name, class_loader); | |
| 1544 } | |
| 1545 | |
| 1546 | |
| 1547 // Used for assertions and verification only | |
| 1548 oop SystemDictionary::find_class_or_placeholder(symbolHandle class_name, | |
| 1549 Handle class_loader) { | |
| 1550 #ifndef ASSERT | |
| 1551 guarantee(VerifyBeforeGC || | |
| 1552 VerifyDuringGC || | |
| 1553 VerifyBeforeExit || | |
| 1554 VerifyAfterGC, "too expensive"); | |
| 1555 #endif | |
| 1556 assert_locked_or_safepoint(SystemDictionary_lock); | |
| 1557 symbolOop class_name_ = class_name(); | |
| 1558 oop class_loader_ = class_loader(); | |
| 1559 | |
| 1560 // First look in the loaded class array | |
| 1561 unsigned int d_hash = dictionary()->compute_hash(class_name, class_loader); | |
| 1562 int d_index = dictionary()->hash_to_index(d_hash); | |
| 1563 oop lookup = find_class(d_index, d_hash, class_name, class_loader); | |
| 1564 | |
| 1565 if (lookup == NULL) { | |
| 1566 // Next try the placeholders | |
| 1567 unsigned int p_hash = placeholders()->compute_hash(class_name,class_loader); | |
| 1568 int p_index = placeholders()->hash_to_index(p_hash); | |
| 1569 lookup = find_placeholder(p_index, p_hash, class_name, class_loader); | |
| 1570 } | |
| 1571 | |
| 1572 return lookup; | |
| 1573 } | |
| 1574 | |
| 1575 | |
| 1576 // Get the next class in the diictionary. | |
| 1577 klassOop SystemDictionary::try_get_next_class() { | |
| 1578 return dictionary()->try_get_next_class(); | |
| 1579 } | |
| 1580 | |
| 1581 | |
| 1582 // ---------------------------------------------------------------------------- | |
| 1583 // Update hierachy. This is done before the new klass has been added to the SystemDictionary. The Recompile_lock | |
| 1584 // is held, to ensure that the compiler is not using the class hierachy, and that deoptimization will kick in | |
| 1585 // before a new class is used. | |
| 1586 | |
| 1587 void SystemDictionary::add_to_hierarchy(instanceKlassHandle k, TRAPS) { | |
| 1588 assert(k.not_null(), "just checking"); | |
| 1589 // Link into hierachy. Make sure the vtables are initialized before linking into | |
| 1590 k->append_to_sibling_list(); // add to superklass/sibling list | |
| 1591 k->process_interfaces(THREAD); // handle all "implements" declarations | |
| 1592 k->set_init_state(instanceKlass::loaded); | |
| 1593 // Now flush all code that depended on old class hierarchy. | |
| 1594 // Note: must be done *after* linking k into the hierarchy (was bug 12/9/97) | |
| 1595 // Also, first reinitialize vtable because it may have gotten out of synch | |
| 1596 // while the new class wasn't connected to the class hierarchy. | |
| 1597 Universe::flush_dependents_on(k); | |
| 1598 } | |
| 1599 | |
| 1600 | |
| 1601 // ---------------------------------------------------------------------------- | |
| 1602 // GC support | |
| 1603 | |
| 1604 // Following roots during mark-sweep is separated in two phases. | |
| 1605 // | |
| 1606 // The first phase follows preloaded classes and all other system | |
| 1607 // classes, since these will never get unloaded anyway. | |
| 1608 // | |
| 1609 // The second phase removes (unloads) unreachable classes from the | |
| 1610 // system dictionary and follows the remaining classes' contents. | |
| 1611 | |
| 1612 void SystemDictionary::always_strong_oops_do(OopClosure* blk) { | |
| 1613 // Follow preloaded classes/mirrors and system loader object | |
| 1614 blk->do_oop(&_java_system_loader); | |
| 1615 preloaded_oops_do(blk); | |
| 1616 always_strong_classes_do(blk); | |
| 1617 } | |
| 1618 | |
| 1619 | |
| 1620 void SystemDictionary::always_strong_classes_do(OopClosure* blk) { | |
| 1621 // Follow all system classes and temporary placeholders in dictionary | |
| 1622 dictionary()->always_strong_classes_do(blk); | |
| 1623 | |
| 1624 // Placeholders. These are *always* strong roots, as they | |
| 1625 // represent classes we're actively loading. | |
| 1626 placeholders_do(blk); | |
| 1627 | |
| 1628 // Loader constraints. We must keep the symbolOop used in the name alive. | |
| 1629 constraints()->always_strong_classes_do(blk); | |
| 1630 | |
| 1631 // Resolution errors keep the symbolOop for the error alive | |
| 1632 resolution_errors()->always_strong_classes_do(blk); | |
| 1633 } | |
| 1634 | |
| 1635 | |
| 1636 void SystemDictionary::placeholders_do(OopClosure* blk) { | |
| 1637 placeholders()->oops_do(blk); | |
| 1638 } | |
| 1639 | |
| 1640 | |
| 1641 bool SystemDictionary::do_unloading(BoolObjectClosure* is_alive) { | |
| 1642 bool result = dictionary()->do_unloading(is_alive); | |
| 1643 constraints()->purge_loader_constraints(is_alive); | |
| 1644 resolution_errors()->purge_resolution_errors(is_alive); | |
| 1645 return result; | |
| 1646 } | |
| 1647 | |
| 1648 | |
| 1649 // The mirrors are scanned by shared_oops_do() which is | |
| 1650 // not called by oops_do(). In order to process oops in | |
| 1651 // a necessary order, shared_oops_do() is call by | |
| 1652 // Universe::oops_do(). | |
| 1653 void SystemDictionary::oops_do(OopClosure* f) { | |
| 1654 // Adjust preloaded classes and system loader object | |
| 1655 f->do_oop(&_java_system_loader); | |
| 1656 preloaded_oops_do(f); | |
| 1657 | |
| 1658 lazily_loaded_oops_do(f); | |
| 1659 | |
| 1660 // Adjust dictionary | |
| 1661 dictionary()->oops_do(f); | |
| 1662 | |
| 1663 // Partially loaded classes | |
| 1664 placeholders()->oops_do(f); | |
| 1665 | |
| 1666 // Adjust constraint table | |
| 1667 constraints()->oops_do(f); | |
| 1668 | |
| 1669 // Adjust resolution error table | |
| 1670 resolution_errors()->oops_do(f); | |
| 1671 } | |
| 1672 | |
| 1673 | |
| 1674 void SystemDictionary::preloaded_oops_do(OopClosure* f) { | |
|
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1675 f->do_oop((oop*) &wk_klass_name_limits[0]); |
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1676 f->do_oop((oop*) &wk_klass_name_limits[1]); |
| 0 | 1677 |
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1678 for (int k = (int)FIRST_WKID; k < (int)WKID_LIMIT; k++) { |
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1679 f->do_oop((oop*) &_well_known_klasses[k]); |
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1680 } |
| 0 | 1681 |
| 1682 { | |
| 1683 for (int i = 0; i < T_VOID+1; i++) { | |
| 1684 if (_box_klasses[i] != NULL) { | |
| 1685 assert(i >= T_BOOLEAN, "checking"); | |
| 1686 f->do_oop((oop*) &_box_klasses[i]); | |
| 1687 } | |
| 1688 } | |
| 1689 } | |
| 1690 | |
| 1691 // The basic type mirrors would have already been processed in | |
| 1692 // Universe::oops_do(), via a call to shared_oops_do(), so should | |
| 1693 // not be processed again. | |
| 1694 | |
| 1695 f->do_oop((oop*) &_system_loader_lock_obj); | |
| 1696 FilteredFieldsMap::klasses_oops_do(f); | |
| 1697 } | |
| 1698 | |
| 1699 void SystemDictionary::lazily_loaded_oops_do(OopClosure* f) { | |
| 1700 f->do_oop((oop*) &_abstract_ownable_synchronizer_klass); | |
| 1701 } | |
| 1702 | |
| 1703 // Just the classes from defining class loaders | |
| 1704 // Don't iterate over placeholders | |
| 1705 void SystemDictionary::classes_do(void f(klassOop)) { | |
| 1706 dictionary()->classes_do(f); | |
| 1707 } | |
| 1708 | |
| 1709 // Added for initialize_itable_for_klass | |
| 1710 // Just the classes from defining class loaders | |
| 1711 // Don't iterate over placeholders | |
| 1712 void SystemDictionary::classes_do(void f(klassOop, TRAPS), TRAPS) { | |
| 1713 dictionary()->classes_do(f, CHECK); | |
| 1714 } | |
| 1715 | |
| 1716 // All classes, and their class loaders | |
| 1717 // Don't iterate over placeholders | |
| 1718 void SystemDictionary::classes_do(void f(klassOop, oop)) { | |
| 1719 dictionary()->classes_do(f); | |
| 1720 } | |
| 1721 | |
| 1722 // All classes, and their class loaders | |
| 1723 // (added for helpers that use HandleMarks and ResourceMarks) | |
| 1724 // Don't iterate over placeholders | |
| 1725 void SystemDictionary::classes_do(void f(klassOop, oop, TRAPS), TRAPS) { | |
| 1726 dictionary()->classes_do(f, CHECK); | |
| 1727 } | |
| 1728 | |
| 1729 void SystemDictionary::placeholders_do(void f(symbolOop, oop)) { | |
| 1730 placeholders()->entries_do(f); | |
| 1731 } | |
| 1732 | |
| 1733 void SystemDictionary::methods_do(void f(methodOop)) { | |
| 1734 dictionary()->methods_do(f); | |
| 1735 } | |
| 1736 | |
| 1737 // ---------------------------------------------------------------------------- | |
| 1738 // Lazily load klasses | |
| 1739 | |
| 1740 void SystemDictionary::load_abstract_ownable_synchronizer_klass(TRAPS) { | |
| 1741 assert(JDK_Version::is_gte_jdk16x_version(), "Must be JDK 1.6 or later"); | |
| 1742 | |
| 1743 // if multiple threads calling this function, only one thread will load | |
| 1744 // the class. The other threads will find the loaded version once the | |
| 1745 // class is loaded. | |
| 1746 klassOop aos = _abstract_ownable_synchronizer_klass; | |
| 1747 if (aos == NULL) { | |
| 1748 klassOop k = resolve_or_fail(vmSymbolHandles::java_util_concurrent_locks_AbstractOwnableSynchronizer(), true, CHECK); | |
| 1749 // Force a fence to prevent any read before the write completes | |
| 1750 OrderAccess::fence(); | |
| 1751 _abstract_ownable_synchronizer_klass = k; | |
| 1752 } | |
| 1753 } | |
| 1754 | |
| 1755 // ---------------------------------------------------------------------------- | |
| 1756 // Initialization | |
| 1757 | |
| 1758 void SystemDictionary::initialize(TRAPS) { | |
| 1759 // Allocate arrays | |
| 1760 assert(dictionary() == NULL, | |
| 1761 "SystemDictionary should only be initialized once"); | |
| 1762 _dictionary = new Dictionary(_nof_buckets); | |
| 1763 _placeholders = new PlaceholderTable(_nof_buckets); | |
| 1764 _number_of_modifications = 0; | |
| 1765 _loader_constraints = new LoaderConstraintTable(_loader_constraint_size); | |
| 1766 _resolution_errors = new ResolutionErrorTable(_resolution_error_size); | |
| 1767 | |
| 1768 // Allocate private object used as system class loader lock | |
| 1769 _system_loader_lock_obj = oopFactory::new_system_objArray(0, CHECK); | |
| 1770 // Initialize basic classes | |
| 1771 initialize_preloaded_classes(CHECK); | |
| 1772 } | |
| 1773 | |
|
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1774 // Compact table of directions on the initialization of klasses: |
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1775 static const short wk_init_info[] = { |
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1776 #define WK_KLASS_INIT_INFO(name, symbol, option) \ |
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1777 ( ((int)vmSymbols::VM_SYMBOL_ENUM_NAME(symbol) \ |
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1778 << SystemDictionary::CEIL_LG_OPTION_LIMIT) \ |
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1779 | (int)SystemDictionary::option ), |
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1780 WK_KLASSES_DO(WK_KLASS_INIT_INFO) |
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1781 #undef WK_KLASS_INIT_INFO |
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1782 0 |
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1783 }; |
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1784 |
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1785 bool SystemDictionary::initialize_wk_klass(WKID id, int init_opt, TRAPS) { |
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1786 assert(id >= (int)FIRST_WKID && id < (int)WKID_LIMIT, "oob"); |
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1787 int info = wk_init_info[id - FIRST_WKID]; |
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1788 int sid = (info >> CEIL_LG_OPTION_LIMIT); |
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1789 symbolHandle symbol = vmSymbolHandles::symbol_handle_at((vmSymbols::SID)sid); |
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1790 klassOop* klassp = &_well_known_klasses[id]; |
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1791 bool must_load = (init_opt < SystemDictionary::Opt); |
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1792 bool try_load = true; |
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1793 if (init_opt == SystemDictionary::Opt_Kernel) { |
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1794 #ifndef KERNEL |
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1795 try_load = false; |
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1796 #endif //KERNEL |
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1797 } |
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1798 if ((*klassp) == NULL && try_load) { |
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1799 if (must_load) { |
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1800 (*klassp) = resolve_or_fail(symbol, true, CHECK_0); // load required class |
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1801 } else { |
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1802 (*klassp) = resolve_or_null(symbol, CHECK_0); // load optional klass |
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1803 } |
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1804 } |
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1805 return ((*klassp) != NULL); |
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1806 } |
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1807 |
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1808 void SystemDictionary::initialize_wk_klasses_until(WKID limit_id, WKID &start_id, TRAPS) { |
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1809 assert((int)start_id <= (int)limit_id, "IDs are out of order!"); |
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1810 for (int id = (int)start_id; id < (int)limit_id; id++) { |
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1811 assert(id >= (int)FIRST_WKID && id < (int)WKID_LIMIT, "oob"); |
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1812 int info = wk_init_info[id - FIRST_WKID]; |
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1813 int sid = (info >> CEIL_LG_OPTION_LIMIT); |
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1814 int opt = (info & right_n_bits(CEIL_LG_OPTION_LIMIT)); |
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1815 |
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1816 initialize_wk_klass((WKID)id, opt, CHECK); |
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1817 |
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1818 // Update limits, so find_well_known_klass can be very fast: |
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1819 symbolOop s = vmSymbols::symbol_at((vmSymbols::SID)sid); |
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1820 if (wk_klass_name_limits[1] == NULL) { |
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1821 wk_klass_name_limits[0] = wk_klass_name_limits[1] = s; |
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1822 } else if (wk_klass_name_limits[1] < s) { |
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1823 wk_klass_name_limits[1] = s; |
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1824 } else if (wk_klass_name_limits[0] > s) { |
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1825 wk_klass_name_limits[0] = s; |
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1826 } |
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1827 } |
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1828 } |
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1829 |
| 0 | 1830 |
| 1831 void SystemDictionary::initialize_preloaded_classes(TRAPS) { | |
|
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1832 assert(WK_KLASS(object_klass) == NULL, "preloaded classes should only be initialized once"); |
| 0 | 1833 // Preload commonly used klasses |
|
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1834 WKID scan = FIRST_WKID; |
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1835 // first do Object, String, Class |
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1836 initialize_wk_klasses_through(WK_KLASS_ENUM_NAME(class_klass), scan, CHECK); |
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1837 |
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1838 debug_only(instanceKlass::verify_class_klass_nonstatic_oop_maps(WK_KLASS(class_klass))); |
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1839 |
| 0 | 1840 // Fixup mirrors for classes loaded before java.lang.Class. |
| 1841 // These calls iterate over the objects currently in the perm gen | |
| 1842 // so calling them at this point is matters (not before when there | |
| 1843 // are fewer objects and not later after there are more objects | |
| 1844 // in the perm gen. | |
| 1845 Universe::initialize_basic_type_mirrors(CHECK); | |
| 1846 Universe::fixup_mirrors(CHECK); | |
| 1847 | |
|
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1848 // do a bunch more: |
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1849 initialize_wk_klasses_through(WK_KLASS_ENUM_NAME(reference_klass), scan, CHECK); |
| 0 | 1850 |
| 1851 // Preload ref klasses and set reference types | |
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1852 instanceKlass::cast(WK_KLASS(reference_klass))->set_reference_type(REF_OTHER); |
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1853 instanceRefKlass::update_nonstatic_oop_maps(WK_KLASS(reference_klass)); |
| 0 | 1854 |
|
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1855 initialize_wk_klasses_through(WK_KLASS_ENUM_NAME(phantom_reference_klass), scan, CHECK); |
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1856 instanceKlass::cast(WK_KLASS(soft_reference_klass))->set_reference_type(REF_SOFT); |
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1857 instanceKlass::cast(WK_KLASS(weak_reference_klass))->set_reference_type(REF_WEAK); |
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1858 instanceKlass::cast(WK_KLASS(final_reference_klass))->set_reference_type(REF_FINAL); |
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1859 instanceKlass::cast(WK_KLASS(phantom_reference_klass))->set_reference_type(REF_PHANTOM); |
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1860 |
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1861 initialize_wk_klasses_until(WKID_LIMIT, scan, CHECK); |
| 0 | 1862 |
|
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1863 _box_klasses[T_BOOLEAN] = WK_KLASS(boolean_klass); |
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1864 _box_klasses[T_CHAR] = WK_KLASS(char_klass); |
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1865 _box_klasses[T_FLOAT] = WK_KLASS(float_klass); |
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1866 _box_klasses[T_DOUBLE] = WK_KLASS(double_klass); |
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1867 _box_klasses[T_BYTE] = WK_KLASS(byte_klass); |
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1868 _box_klasses[T_SHORT] = WK_KLASS(short_klass); |
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1869 _box_klasses[T_INT] = WK_KLASS(int_klass); |
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1870 _box_klasses[T_LONG] = WK_KLASS(long_klass); |
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1871 //_box_klasses[T_OBJECT] = WK_KLASS(object_klass); |
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1872 //_box_klasses[T_ARRAY] = WK_KLASS(object_klass); |
| 0 | 1873 |
| 1874 #ifdef KERNEL | |
|
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1875 if (sun_jkernel_DownloadManager_klass() == NULL) { |
| 0 | 1876 warning("Cannot find sun/jkernel/DownloadManager"); |
| 1877 } | |
| 1878 #endif // KERNEL | |
| 1879 { // Compute whether we should use loadClass or loadClassInternal when loading classes. | |
| 1880 methodOop method = instanceKlass::cast(classloader_klass())->find_method(vmSymbols::loadClassInternal_name(), vmSymbols::string_class_signature()); | |
| 1881 _has_loadClassInternal = (method != NULL); | |
| 1882 } | |
| 1883 | |
| 1884 { // Compute whether we should use checkPackageAccess or NOT | |
| 1885 methodOop method = instanceKlass::cast(classloader_klass())->find_method(vmSymbols::checkPackageAccess_name(), vmSymbols::class_protectiondomain_signature()); | |
| 1886 _has_checkPackageAccess = (method != NULL); | |
| 1887 } | |
| 1888 } | |
| 1889 | |
| 1890 // Tells if a given klass is a box (wrapper class, such as java.lang.Integer). | |
| 1891 // If so, returns the basic type it holds. If not, returns T_OBJECT. | |
| 1892 BasicType SystemDictionary::box_klass_type(klassOop k) { | |
| 1893 assert(k != NULL, ""); | |
| 1894 for (int i = T_BOOLEAN; i < T_VOID+1; i++) { | |
| 1895 if (_box_klasses[i] == k) | |
| 1896 return (BasicType)i; | |
| 1897 } | |
| 1898 return T_OBJECT; | |
| 1899 } | |
| 1900 | |
| 1901 // Constraints on class loaders. The details of the algorithm can be | |
| 1902 // found in the OOPSLA'98 paper "Dynamic Class Loading in the Java | |
| 1903 // Virtual Machine" by Sheng Liang and Gilad Bracha. The basic idea is | |
| 1904 // that the system dictionary needs to maintain a set of contraints that | |
| 1905 // must be satisfied by all classes in the dictionary. | |
| 1906 // if defining is true, then LinkageError if already in systemDictionary | |
| 1907 // if initiating loader, then ok if instanceKlass matches existing entry | |
| 1908 | |
| 1909 void SystemDictionary::check_constraints(int d_index, unsigned int d_hash, | |
| 1910 instanceKlassHandle k, | |
| 1911 Handle class_loader, bool defining, | |
| 1912 TRAPS) { | |
| 1913 const char *linkage_error = NULL; | |
| 1914 { | |
| 1915 symbolHandle name (THREAD, k->name()); | |
| 1916 MutexLocker mu(SystemDictionary_lock, THREAD); | |
| 1917 | |
| 1918 klassOop check = find_class(d_index, d_hash, name, class_loader); | |
| 1919 if (check != (klassOop)NULL) { | |
| 1920 // if different instanceKlass - duplicate class definition, | |
| 1921 // else - ok, class loaded by a different thread in parallel, | |
| 1922 // we should only have found it if it was done loading and ok to use | |
| 1923 // system dictionary only holds instance classes, placeholders | |
| 1924 // also holds array classes | |
| 1925 | |
| 1926 assert(check->klass_part()->oop_is_instance(), "noninstance in systemdictionary"); | |
| 1927 if ((defining == true) || (k() != check)) { | |
| 1928 linkage_error = "loader (instance of %s): attempted duplicate class " | |
| 1929 "definition for name: \"%s\""; | |
| 1930 } else { | |
| 1931 return; | |
| 1932 } | |
| 1933 } | |
| 1934 | |
| 1935 #ifdef ASSERT | |
| 1936 unsigned int p_hash = placeholders()->compute_hash(name, class_loader); | |
| 1937 int p_index = placeholders()->hash_to_index(p_hash); | |
| 1938 symbolOop ph_check = find_placeholder(p_index, p_hash, name, class_loader); | |
| 1939 assert(ph_check == NULL || ph_check == name(), "invalid symbol"); | |
| 1940 #endif | |
| 1941 | |
| 1942 if (linkage_error == NULL) { | |
| 1943 if (constraints()->check_or_update(k, class_loader, name) == false) { | |
| 1944 linkage_error = "loader constraint violation: loader (instance of %s)" | |
| 1945 " previously initiated loading for a different type with name \"%s\""; | |
| 1946 } | |
| 1947 } | |
| 1948 } | |
| 1949 | |
| 1950 // Throw error now if needed (cannot throw while holding | |
| 1951 // SystemDictionary_lock because of rank ordering) | |
| 1952 | |
| 1953 if (linkage_error) { | |
| 1954 ResourceMark rm(THREAD); | |
| 1955 const char* class_loader_name = loader_name(class_loader()); | |
| 1956 char* type_name = k->name()->as_C_string(); | |
| 1957 size_t buflen = strlen(linkage_error) + strlen(class_loader_name) + | |
| 1958 strlen(type_name); | |
| 1959 char* buf = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, buflen); | |
| 1960 jio_snprintf(buf, buflen, linkage_error, class_loader_name, type_name); | |
| 1961 THROW_MSG(vmSymbols::java_lang_LinkageError(), buf); | |
| 1962 } | |
| 1963 } | |
| 1964 | |
| 1965 | |
| 1966 // Update system dictionary - done after check_constraint and add_to_hierachy | |
| 1967 // have been called. | |
| 1968 void SystemDictionary::update_dictionary(int d_index, unsigned int d_hash, | |
| 1969 int p_index, unsigned int p_hash, | |
| 1970 instanceKlassHandle k, | |
| 1971 Handle class_loader, | |
| 1972 TRAPS) { | |
| 1973 // Compile_lock prevents systemDictionary updates during compilations | |
| 1974 assert_locked_or_safepoint(Compile_lock); | |
| 1975 symbolHandle name (THREAD, k->name()); | |
| 1976 | |
| 1977 { | |
| 1978 MutexLocker mu1(SystemDictionary_lock, THREAD); | |
| 1979 | |
| 1980 // See whether biased locking is enabled and if so set it for this | |
| 1981 // klass. | |
| 1982 // Note that this must be done past the last potential blocking | |
| 1983 // point / safepoint. We enable biased locking lazily using a | |
| 1984 // VM_Operation to iterate the SystemDictionary and installing the | |
| 1985 // biasable mark word into each instanceKlass's prototype header. | |
| 1986 // To avoid race conditions where we accidentally miss enabling the | |
| 1987 // optimization for one class in the process of being added to the | |
| 1988 // dictionary, we must not safepoint after the test of | |
| 1989 // BiasedLocking::enabled(). | |
| 1990 if (UseBiasedLocking && BiasedLocking::enabled()) { | |
| 1991 // Set biased locking bit for all loaded classes; it will be | |
| 1992 // cleared if revocation occurs too often for this type | |
| 1993 // NOTE that we must only do this when the class is initally | |
| 1994 // defined, not each time it is referenced from a new class loader | |
| 1995 if (k->class_loader() == class_loader()) { | |
| 1996 k->set_prototype_header(markOopDesc::biased_locking_prototype()); | |
| 1997 } | |
| 1998 } | |
| 1999 | |
| 2000 // Check for a placeholder. If there, remove it and make a | |
| 2001 // new system dictionary entry. | |
| 2002 placeholders()->find_and_remove(p_index, p_hash, name, class_loader, THREAD); | |
| 2003 klassOop sd_check = find_class(d_index, d_hash, name, class_loader); | |
| 2004 if (sd_check == NULL) { | |
| 2005 dictionary()->add_klass(name, class_loader, k); | |
| 2006 notice_modification(); | |
| 2007 } | |
| 2008 #ifdef ASSERT | |
| 2009 sd_check = find_class(d_index, d_hash, name, class_loader); | |
| 2010 assert (sd_check != NULL, "should have entry in system dictionary"); | |
| 2011 // Changed to allow PH to remain to complete class circularity checking | |
| 2012 // while only one thread can define a class at one time, multiple | |
| 2013 // classes can resolve the superclass for a class at one time, | |
| 2014 // and the placeholder is used to track that | |
| 2015 // symbolOop ph_check = find_placeholder(p_index, p_hash, name, class_loader); | |
| 2016 // assert (ph_check == NULL, "should not have a placeholder entry"); | |
| 2017 #endif | |
| 2018 SystemDictionary_lock->notify_all(); | |
| 2019 } | |
| 2020 } | |
| 2021 | |
| 2022 | |
| 2023 klassOop SystemDictionary::find_constrained_instance_or_array_klass( | |
| 2024 symbolHandle class_name, Handle class_loader, TRAPS) { | |
| 2025 | |
| 2026 // First see if it has been loaded directly. | |
| 2027 // Force the protection domain to be null. (This removes protection checks.) | |
| 2028 Handle no_protection_domain; | |
| 2029 klassOop klass = find_instance_or_array_klass(class_name, class_loader, | |
| 2030 no_protection_domain, CHECK_NULL); | |
| 2031 if (klass != NULL) | |
| 2032 return klass; | |
| 2033 | |
| 2034 // Now look to see if it has been loaded elsewhere, and is subject to | |
| 2035 // a loader constraint that would require this loader to return the | |
| 2036 // klass that is already loaded. | |
| 2037 if (FieldType::is_array(class_name())) { | |
| 2038 // Array classes are hard because their klassOops are not kept in the | |
| 2039 // constraint table. The array klass may be constrained, but the elem class | |
| 2040 // may not be. | |
| 2041 jint dimension; | |
| 2042 symbolOop object_key; | |
| 2043 BasicType t = FieldType::get_array_info(class_name(), &dimension, | |
| 2044 &object_key, CHECK_(NULL)); | |
| 2045 if (t != T_OBJECT) { | |
| 2046 klass = Universe::typeArrayKlassObj(t); | |
| 2047 } else { | |
| 2048 symbolHandle elem_name(THREAD, object_key); | |
| 2049 MutexLocker mu(SystemDictionary_lock, THREAD); | |
| 2050 klass = constraints()->find_constrained_elem_klass(class_name, elem_name, class_loader, THREAD); | |
| 2051 } | |
| 2052 if (klass != NULL) { | |
| 2053 klass = Klass::cast(klass)->array_klass_or_null(dimension); | |
| 2054 } | |
| 2055 } else { | |
| 2056 MutexLocker mu(SystemDictionary_lock, THREAD); | |
| 2057 // Non-array classes are easy: simply check the constraint table. | |
| 2058 klass = constraints()->find_constrained_klass(class_name, class_loader); | |
| 2059 } | |
| 2060 | |
| 2061 return klass; | |
| 2062 } | |
| 2063 | |
| 2064 | |
| 2065 bool SystemDictionary::add_loader_constraint(symbolHandle class_name, | |
| 2066 Handle class_loader1, | |
| 2067 Handle class_loader2, | |
| 2068 Thread* THREAD) { | |
| 2069 unsigned int d_hash1 = dictionary()->compute_hash(class_name, class_loader1); | |
| 2070 int d_index1 = dictionary()->hash_to_index(d_hash1); | |
| 2071 | |
| 2072 unsigned int d_hash2 = dictionary()->compute_hash(class_name, class_loader2); | |
| 2073 int d_index2 = dictionary()->hash_to_index(d_hash2); | |
| 2074 | |
| 2075 { | |
| 2076 MutexLocker mu_s(SystemDictionary_lock, THREAD); | |
| 2077 | |
| 2078 // Better never do a GC while we're holding these oops | |
| 2079 No_Safepoint_Verifier nosafepoint; | |
| 2080 | |
| 2081 klassOop klass1 = find_class(d_index1, d_hash1, class_name, class_loader1); | |
| 2082 klassOop klass2 = find_class(d_index2, d_hash2, class_name, class_loader2); | |
| 2083 return constraints()->add_entry(class_name, klass1, class_loader1, | |
| 2084 klass2, class_loader2); | |
| 2085 } | |
| 2086 } | |
| 2087 | |
| 2088 // Add entry to resolution error table to record the error when the first | |
| 2089 // attempt to resolve a reference to a class has failed. | |
| 2090 void SystemDictionary::add_resolution_error(constantPoolHandle pool, int which, symbolHandle error) { | |
| 2091 unsigned int hash = resolution_errors()->compute_hash(pool, which); | |
| 2092 int index = resolution_errors()->hash_to_index(hash); | |
| 2093 { | |
| 2094 MutexLocker ml(SystemDictionary_lock, Thread::current()); | |
| 2095 resolution_errors()->add_entry(index, hash, pool, which, error); | |
| 2096 } | |
| 2097 } | |
| 2098 | |
| 2099 // Lookup resolution error table. Returns error if found, otherwise NULL. | |
| 2100 symbolOop SystemDictionary::find_resolution_error(constantPoolHandle pool, int which) { | |
| 2101 unsigned int hash = resolution_errors()->compute_hash(pool, which); | |
| 2102 int index = resolution_errors()->hash_to_index(hash); | |
| 2103 { | |
| 2104 MutexLocker ml(SystemDictionary_lock, Thread::current()); | |
| 2105 ResolutionErrorEntry* entry = resolution_errors()->find_entry(index, hash, pool, which); | |
| 2106 return (entry != NULL) ? entry->error() : (symbolOop)NULL; | |
| 2107 } | |
| 2108 } | |
| 2109 | |
| 2110 | |
| 2111 // Make sure all class components (including arrays) in the given | |
| 2112 // signature will be resolved to the same class in both loaders. | |
| 2113 // Returns the name of the type that failed a loader constraint check, or | |
| 2114 // NULL if no constraint failed. The returned C string needs cleaning up | |
| 2115 // with a ResourceMark in the caller | |
| 2116 char* SystemDictionary::check_signature_loaders(symbolHandle signature, | |
| 2117 Handle loader1, Handle loader2, | |
| 2118 bool is_method, TRAPS) { | |
| 2119 // Nothing to do if loaders are the same. | |
| 2120 if (loader1() == loader2()) { | |
| 2121 return NULL; | |
| 2122 } | |
| 2123 | |
| 2124 SignatureStream sig_strm(signature, is_method); | |
| 2125 while (!sig_strm.is_done()) { | |
| 2126 if (sig_strm.is_object()) { | |
| 2127 symbolOop s = sig_strm.as_symbol(CHECK_NULL); | |
| 2128 symbolHandle sig (THREAD, s); | |
| 2129 if (!add_loader_constraint(sig, loader1, loader2, THREAD)) { | |
| 2130 return sig()->as_C_string(); | |
| 2131 } | |
| 2132 } | |
| 2133 sig_strm.next(); | |
| 2134 } | |
| 2135 return NULL; | |
| 2136 } | |
| 2137 | |
| 2138 | |
| 2139 // Since the identity hash code for symbols changes when the symbols are | |
| 2140 // moved from the regular perm gen (hash in the mark word) to the shared | |
| 2141 // spaces (hash is the address), the classes loaded into the dictionary | |
| 2142 // may be in the wrong buckets. | |
| 2143 | |
| 2144 void SystemDictionary::reorder_dictionary() { | |
| 2145 dictionary()->reorder_dictionary(); | |
| 2146 } | |
| 2147 | |
| 2148 | |
| 2149 void SystemDictionary::copy_buckets(char** top, char* end) { | |
| 2150 dictionary()->copy_buckets(top, end); | |
| 2151 } | |
| 2152 | |
| 2153 | |
| 2154 void SystemDictionary::copy_table(char** top, char* end) { | |
| 2155 dictionary()->copy_table(top, end); | |
| 2156 } | |
| 2157 | |
| 2158 | |
| 2159 void SystemDictionary::reverse() { | |
| 2160 dictionary()->reverse(); | |
| 2161 } | |
| 2162 | |
| 2163 int SystemDictionary::number_of_classes() { | |
| 2164 return dictionary()->number_of_entries(); | |
| 2165 } | |
| 2166 | |
| 2167 | |
| 2168 // ---------------------------------------------------------------------------- | |
| 2169 #ifndef PRODUCT | |
| 2170 | |
| 2171 void SystemDictionary::print() { | |
| 2172 dictionary()->print(); | |
| 2173 | |
| 2174 // Placeholders | |
| 2175 GCMutexLocker mu(SystemDictionary_lock); | |
| 2176 placeholders()->print(); | |
| 2177 | |
| 2178 // loader constraints - print under SD_lock | |
| 2179 constraints()->print(); | |
| 2180 } | |
| 2181 | |
| 2182 #endif | |
| 2183 | |
| 2184 void SystemDictionary::verify() { | |
| 2185 guarantee(dictionary() != NULL, "Verify of system dictionary failed"); | |
| 2186 guarantee(constraints() != NULL, | |
| 2187 "Verify of loader constraints failed"); | |
| 2188 guarantee(dictionary()->number_of_entries() >= 0 && | |
| 2189 placeholders()->number_of_entries() >= 0, | |
| 2190 "Verify of system dictionary failed"); | |
| 2191 | |
| 2192 // Verify dictionary | |
| 2193 dictionary()->verify(); | |
| 2194 | |
| 2195 GCMutexLocker mu(SystemDictionary_lock); | |
| 2196 placeholders()->verify(); | |
| 2197 | |
| 2198 // Verify constraint table | |
| 2199 guarantee(constraints() != NULL, "Verify of loader constraints failed"); | |
| 2200 constraints()->verify(dictionary()); | |
| 2201 } | |
| 2202 | |
| 2203 | |
| 2204 void SystemDictionary::verify_obj_klass_present(Handle obj, | |
| 2205 symbolHandle class_name, | |
| 2206 Handle class_loader) { | |
| 2207 GCMutexLocker mu(SystemDictionary_lock); | |
| 2208 oop probe = find_class_or_placeholder(class_name, class_loader); | |
| 2209 if (probe == NULL) { | |
| 2210 probe = SystemDictionary::find_shared_class(class_name); | |
| 2211 } | |
| 2212 guarantee(probe != NULL && | |
| 2213 (!probe->is_klass() || probe == obj()), | |
| 2214 "Loaded klasses should be in SystemDictionary"); | |
| 2215 } | |
| 2216 | |
| 2217 #ifndef PRODUCT | |
| 2218 | |
| 2219 // statistics code | |
| 2220 class ClassStatistics: AllStatic { | |
| 2221 private: | |
| 2222 static int nclasses; // number of classes | |
| 2223 static int nmethods; // number of methods | |
| 2224 static int nmethoddata; // number of methodData | |
| 2225 static int class_size; // size of class objects in words | |
| 2226 static int method_size; // size of method objects in words | |
| 2227 static int debug_size; // size of debug info in methods | |
| 2228 static int methoddata_size; // size of methodData objects in words | |
| 2229 | |
| 2230 static void do_class(klassOop k) { | |
| 2231 nclasses++; | |
| 2232 class_size += k->size(); | |
| 2233 if (k->klass_part()->oop_is_instance()) { | |
| 2234 instanceKlass* ik = (instanceKlass*)k->klass_part(); | |
| 2235 class_size += ik->methods()->size(); | |
| 2236 class_size += ik->constants()->size(); | |
| 2237 class_size += ik->local_interfaces()->size(); | |
| 2238 class_size += ik->transitive_interfaces()->size(); | |
| 2239 // We do not have to count implementors, since we only store one! | |
| 2240 class_size += ik->fields()->size(); | |
| 2241 } | |
| 2242 } | |
| 2243 | |
| 2244 static void do_method(methodOop m) { | |
| 2245 nmethods++; | |
| 2246 method_size += m->size(); | |
| 2247 // class loader uses same objArray for empty vectors, so don't count these | |
| 2248 if (m->exception_table()->length() != 0) method_size += m->exception_table()->size(); | |
| 2249 if (m->has_stackmap_table()) { | |
| 2250 method_size += m->stackmap_data()->size(); | |
| 2251 } | |
| 2252 | |
| 2253 methodDataOop mdo = m->method_data(); | |
| 2254 if (mdo != NULL) { | |
| 2255 nmethoddata++; | |
| 2256 methoddata_size += mdo->size(); | |
| 2257 } | |
| 2258 } | |
| 2259 | |
| 2260 public: | |
| 2261 static void print() { | |
| 2262 SystemDictionary::classes_do(do_class); | |
| 2263 SystemDictionary::methods_do(do_method); | |
| 2264 tty->print_cr("Class statistics:"); | |
| 2265 tty->print_cr("%d classes (%d bytes)", nclasses, class_size * oopSize); | |
| 2266 tty->print_cr("%d methods (%d bytes = %d base + %d debug info)", nmethods, | |
| 2267 (method_size + debug_size) * oopSize, method_size * oopSize, debug_size * oopSize); | |
| 2268 tty->print_cr("%d methoddata (%d bytes)", nmethoddata, methoddata_size * oopSize); | |
| 2269 } | |
| 2270 }; | |
| 2271 | |
| 2272 | |
| 2273 int ClassStatistics::nclasses = 0; | |
| 2274 int ClassStatistics::nmethods = 0; | |
| 2275 int ClassStatistics::nmethoddata = 0; | |
| 2276 int ClassStatistics::class_size = 0; | |
| 2277 int ClassStatistics::method_size = 0; | |
| 2278 int ClassStatistics::debug_size = 0; | |
| 2279 int ClassStatistics::methoddata_size = 0; | |
| 2280 | |
| 2281 void SystemDictionary::print_class_statistics() { | |
| 2282 ResourceMark rm; | |
| 2283 ClassStatistics::print(); | |
| 2284 } | |
| 2285 | |
| 2286 | |
| 2287 class MethodStatistics: AllStatic { | |
| 2288 public: | |
| 2289 enum { | |
| 2290 max_parameter_size = 10 | |
| 2291 }; | |
| 2292 private: | |
| 2293 | |
| 2294 static int _number_of_methods; | |
| 2295 static int _number_of_final_methods; | |
| 2296 static int _number_of_static_methods; | |
| 2297 static int _number_of_native_methods; | |
| 2298 static int _number_of_synchronized_methods; | |
| 2299 static int _number_of_profiled_methods; | |
| 2300 static int _number_of_bytecodes; | |
| 2301 static int _parameter_size_profile[max_parameter_size]; | |
| 2302 static int _bytecodes_profile[Bytecodes::number_of_java_codes]; | |
| 2303 | |
| 2304 static void initialize() { | |
| 2305 _number_of_methods = 0; | |
| 2306 _number_of_final_methods = 0; | |
| 2307 _number_of_static_methods = 0; | |
| 2308 _number_of_native_methods = 0; | |
| 2309 _number_of_synchronized_methods = 0; | |
| 2310 _number_of_profiled_methods = 0; | |
| 2311 _number_of_bytecodes = 0; | |
| 2312 for (int i = 0; i < max_parameter_size ; i++) _parameter_size_profile[i] = 0; | |
| 2313 for (int j = 0; j < Bytecodes::number_of_java_codes; j++) _bytecodes_profile [j] = 0; | |
| 2314 }; | |
| 2315 | |
| 2316 static void do_method(methodOop m) { | |
| 2317 _number_of_methods++; | |
| 2318 // collect flag info | |
| 2319 if (m->is_final() ) _number_of_final_methods++; | |
| 2320 if (m->is_static() ) _number_of_static_methods++; | |
| 2321 if (m->is_native() ) _number_of_native_methods++; | |
| 2322 if (m->is_synchronized()) _number_of_synchronized_methods++; | |
| 2323 if (m->method_data() != NULL) _number_of_profiled_methods++; | |
| 2324 // collect parameter size info (add one for receiver, if any) | |
| 2325 _parameter_size_profile[MIN2(m->size_of_parameters() + (m->is_static() ? 0 : 1), max_parameter_size - 1)]++; | |
| 2326 // collect bytecodes info | |
| 2327 { | |
| 2328 Thread *thread = Thread::current(); | |
| 2329 HandleMark hm(thread); | |
| 2330 BytecodeStream s(methodHandle(thread, m)); | |
| 2331 Bytecodes::Code c; | |
| 2332 while ((c = s.next()) >= 0) { | |
| 2333 _number_of_bytecodes++; | |
| 2334 _bytecodes_profile[c]++; | |
| 2335 } | |
| 2336 } | |
| 2337 } | |
| 2338 | |
| 2339 public: | |
| 2340 static void print() { | |
| 2341 initialize(); | |
| 2342 SystemDictionary::methods_do(do_method); | |
| 2343 // generate output | |
| 2344 tty->cr(); | |
| 2345 tty->print_cr("Method statistics (static):"); | |
| 2346 // flag distribution | |
| 2347 tty->cr(); | |
| 2348 tty->print_cr("%6d final methods %6.1f%%", _number_of_final_methods , _number_of_final_methods * 100.0F / _number_of_methods); | |
| 2349 tty->print_cr("%6d static methods %6.1f%%", _number_of_static_methods , _number_of_static_methods * 100.0F / _number_of_methods); | |
| 2350 tty->print_cr("%6d native methods %6.1f%%", _number_of_native_methods , _number_of_native_methods * 100.0F / _number_of_methods); | |
| 2351 tty->print_cr("%6d synchronized methods %6.1f%%", _number_of_synchronized_methods, _number_of_synchronized_methods * 100.0F / _number_of_methods); | |
| 2352 tty->print_cr("%6d profiled methods %6.1f%%", _number_of_profiled_methods, _number_of_profiled_methods * 100.0F / _number_of_methods); | |
| 2353 // parameter size profile | |
| 2354 tty->cr(); | |
| 2355 { int tot = 0; | |
| 2356 int avg = 0; | |
| 2357 for (int i = 0; i < max_parameter_size; i++) { | |
| 2358 int n = _parameter_size_profile[i]; | |
| 2359 tot += n; | |
| 2360 avg += n*i; | |
| 2361 tty->print_cr("parameter size = %1d: %6d methods %5.1f%%", i, n, n * 100.0F / _number_of_methods); | |
| 2362 } | |
| 2363 assert(tot == _number_of_methods, "should be the same"); | |
| 2364 tty->print_cr(" %6d methods 100.0%%", _number_of_methods); | |
| 2365 tty->print_cr("(average parameter size = %3.1f including receiver, if any)", (float)avg / _number_of_methods); | |
| 2366 } | |
| 2367 // bytecodes profile | |
| 2368 tty->cr(); | |
| 2369 { int tot = 0; | |
| 2370 for (int i = 0; i < Bytecodes::number_of_java_codes; i++) { | |
| 2371 if (Bytecodes::is_defined(i)) { | |
| 2372 Bytecodes::Code c = Bytecodes::cast(i); | |
| 2373 int n = _bytecodes_profile[c]; | |
| 2374 tot += n; | |
| 2375 tty->print_cr("%9d %7.3f%% %s", n, n * 100.0F / _number_of_bytecodes, Bytecodes::name(c)); | |
| 2376 } | |
| 2377 } | |
| 2378 assert(tot == _number_of_bytecodes, "should be the same"); | |
| 2379 tty->print_cr("%9d 100.000%%", _number_of_bytecodes); | |
| 2380 } | |
| 2381 tty->cr(); | |
| 2382 } | |
| 2383 }; | |
| 2384 | |
| 2385 int MethodStatistics::_number_of_methods; | |
| 2386 int MethodStatistics::_number_of_final_methods; | |
| 2387 int MethodStatistics::_number_of_static_methods; | |
| 2388 int MethodStatistics::_number_of_native_methods; | |
| 2389 int MethodStatistics::_number_of_synchronized_methods; | |
| 2390 int MethodStatistics::_number_of_profiled_methods; | |
| 2391 int MethodStatistics::_number_of_bytecodes; | |
| 2392 int MethodStatistics::_parameter_size_profile[MethodStatistics::max_parameter_size]; | |
| 2393 int MethodStatistics::_bytecodes_profile[Bytecodes::number_of_java_codes]; | |
| 2394 | |
| 2395 | |
| 2396 void SystemDictionary::print_method_statistics() { | |
| 2397 MethodStatistics::print(); | |
| 2398 } | |
| 2399 | |
| 2400 #endif // PRODUCT |