1 /* 2 * Copyright (c) 1998, 2017, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 * 23 */ 24 25 #ifndef SHARE_VM_PRIMS_JVMTIEXPORT_HPP 26 #define SHARE_VM_PRIMS_JVMTIEXPORT_HPP 27 28 #include "jvmtifiles/jvmti.h" 29 #include "memory/allocation.hpp" 30 #include "memory/iterator.hpp" 31 #include "oops/oop.hpp" 32 #include "oops/oopsHierarchy.hpp" 33 #include "runtime/frame.hpp" 34 #include "runtime/handles.hpp" 35 #include "utilities/globalDefinitions.hpp" 36 #include "utilities/growableArray.hpp" 37 #include "utilities/macros.hpp" 38 39 // Must be included after jvmti.h. 40 #include "jvmticmlr.h" 41 42 // Forward declarations 43 44 class JvmtiEventControllerPrivate; 45 class JvmtiManageCapabilities; 46 class JvmtiEnv; 47 class JvmtiThreadState; 48 49 #define JVMTI_SUPPORT_FLAG(key) \ 50 private: \ 51 static bool _##key; \ 52 public: \ 53 inline static void set_##key(bool on) { \ 54 JVMTI_ONLY(_##key = (on != 0)); \ 55 NOT_JVMTI(report_unsupported(on)); \ 56 } \ 57 inline static bool key() { \ 58 JVMTI_ONLY(return _##key); \ 59 NOT_JVMTI(return false); \ 60 } 61 62 63 // This class contains the JVMTI interface for the rest of hotspot. 64 // 65 class JvmtiExport : public AllStatic { 66 friend class VMStructs; 67 friend class CompileReplay; 68 69 private: 70 71 #if INCLUDE_JVMTI 72 static int _field_access_count; 73 static int _field_modification_count; 74 75 static bool _can_access_local_variables; 76 static bool _can_hotswap_or_post_breakpoint; 77 static bool _can_modify_any_class; 78 static bool _can_walk_any_space; 79 #endif // INCLUDE_JVMTI 80 81 JVMTI_SUPPORT_FLAG(can_get_source_debug_extension) 82 JVMTI_SUPPORT_FLAG(can_maintain_original_method_order) 83 JVMTI_SUPPORT_FLAG(can_post_interpreter_events) 84 JVMTI_SUPPORT_FLAG(can_post_on_exceptions) 85 JVMTI_SUPPORT_FLAG(can_post_breakpoint) 86 JVMTI_SUPPORT_FLAG(can_post_field_access) 87 JVMTI_SUPPORT_FLAG(can_post_field_modification) 88 JVMTI_SUPPORT_FLAG(can_post_method_entry) 89 JVMTI_SUPPORT_FLAG(can_post_method_exit) 90 JVMTI_SUPPORT_FLAG(can_pop_frame) 91 JVMTI_SUPPORT_FLAG(can_force_early_return) 92 93 JVMTI_SUPPORT_FLAG(early_vmstart_recorded) 94 95 friend class JvmtiEventControllerPrivate; // should only modify these flags 96 JVMTI_SUPPORT_FLAG(should_post_single_step) 97 JVMTI_SUPPORT_FLAG(should_post_field_access) 98 JVMTI_SUPPORT_FLAG(should_post_field_modification) 99 JVMTI_SUPPORT_FLAG(should_post_class_load) 100 JVMTI_SUPPORT_FLAG(should_post_class_prepare) 101 JVMTI_SUPPORT_FLAG(should_post_class_unload) 102 JVMTI_SUPPORT_FLAG(should_post_native_method_bind) 103 JVMTI_SUPPORT_FLAG(should_post_compiled_method_load) 104 JVMTI_SUPPORT_FLAG(should_post_compiled_method_unload) 105 JVMTI_SUPPORT_FLAG(should_post_dynamic_code_generated) 106 JVMTI_SUPPORT_FLAG(should_post_monitor_contended_enter) 107 JVMTI_SUPPORT_FLAG(should_post_monitor_contended_entered) 108 JVMTI_SUPPORT_FLAG(should_post_monitor_wait) 109 JVMTI_SUPPORT_FLAG(should_post_monitor_waited) 110 JVMTI_SUPPORT_FLAG(should_post_data_dump) 111 JVMTI_SUPPORT_FLAG(should_post_garbage_collection_start) 112 JVMTI_SUPPORT_FLAG(should_post_garbage_collection_finish) 113 JVMTI_SUPPORT_FLAG(should_post_on_exceptions) 114 115 // ------ the below maybe don't have to be (but are for now) 116 // fixed conditions here ------------ 117 // any events can be enabled 118 JVMTI_SUPPORT_FLAG(should_post_thread_life) 119 JVMTI_SUPPORT_FLAG(should_post_object_free) 120 JVMTI_SUPPORT_FLAG(should_post_resource_exhausted) 121 122 // we are holding objects on the heap - need to talk to GC - e.g. 123 // breakpoint info 124 JVMTI_SUPPORT_FLAG(should_clean_up_heap_objects) 125 JVMTI_SUPPORT_FLAG(should_post_vm_object_alloc) 126 127 // If flag cannot be implemented, give an error if on=true 128 static void report_unsupported(bool on); 129 130 // these should only be called by the friend class 131 friend class JvmtiManageCapabilities; 132 inline static void set_can_modify_any_class(bool on) { 133 JVMTI_ONLY(_can_modify_any_class = (on != 0);) 134 } 135 inline static void set_can_access_local_variables(bool on) { 136 JVMTI_ONLY(_can_access_local_variables = (on != 0);) 137 } 138 inline static void set_can_hotswap_or_post_breakpoint(bool on) { 139 JVMTI_ONLY(_can_hotswap_or_post_breakpoint = (on != 0);) 140 } 141 inline static void set_can_walk_any_space(bool on) { 142 JVMTI_ONLY(_can_walk_any_space = (on != 0);) 143 } 144 145 enum { 146 JVMTI_VERSION_MASK = 0x70000000, 147 JVMTI_VERSION_VALUE = 0x30000000, 148 JVMDI_VERSION_VALUE = 0x20000000 149 }; 150 151 static void post_field_modification(JavaThread *thread, Method* method, address location, 152 Klass* field_klass, Handle object, jfieldID field, 153 char sig_type, jvalue *value); 154 155 156 // posts a DynamicCodeGenerated event (internal/private implementation). 157 // The public post_dynamic_code_generated* functions make use of the 158 // internal implementation. Also called from JvmtiDeferredEvent::post() 159 static void post_dynamic_code_generated_internal(const char *name, const void *code_begin, const void *code_end) NOT_JVMTI_RETURN; 160 161 private: 162 163 // GenerateEvents support to allow posting of CompiledMethodLoad and 164 // DynamicCodeGenerated events for a given environment. 165 friend class JvmtiCodeBlobEvents; 166 167 static void post_compiled_method_load(JvmtiEnv* env, const jmethodID method, const jint length, 168 const void *code_begin, const jint map_length, 169 const jvmtiAddrLocationMap* map) NOT_JVMTI_RETURN; 170 static void post_dynamic_code_generated(JvmtiEnv* env, const char *name, const void *code_begin, 171 const void *code_end) NOT_JVMTI_RETURN; 172 173 // This flag indicates whether RedefineClasses() has ever redefined 174 // one or more classes during the lifetime of the VM. The flag should 175 // only be set by the friend class and can be queried by other sub 176 // systems as needed to relax invariant checks. 177 static bool _has_redefined_a_class; 178 friend class VM_RedefineClasses; 179 inline static void set_has_redefined_a_class() { 180 JVMTI_ONLY(_has_redefined_a_class = true;) 181 } 182 // Flag to indicate if the compiler has recorded all dependencies. When the 183 // can_redefine_classes capability is enabled in the OnLoad phase then the compiler 184 // records all dependencies from startup. However if the capability is first 185 // enabled some time later then the dependencies recorded by the compiler 186 // are incomplete. This flag is used by RedefineClasses to know if the 187 // dependency information is complete or not. 188 static bool _all_dependencies_are_recorded; 189 190 public: 191 inline static bool has_redefined_a_class() { 192 JVMTI_ONLY(return _has_redefined_a_class); 193 NOT_JVMTI(return false); 194 } 195 196 inline static bool all_dependencies_are_recorded() { 197 return _all_dependencies_are_recorded; 198 } 199 200 inline static void set_all_dependencies_are_recorded(bool on) { 201 _all_dependencies_are_recorded = (on != 0); 202 } 203 204 // Add read edges to the unnamed modules of the bootstrap and app class loaders 205 static void add_default_read_edges(Handle h_module, TRAPS) NOT_JVMTI_RETURN; 206 207 // Add a read edge to the module 208 static jvmtiError add_module_reads(Handle module, Handle to_module, TRAPS); 209 210 // Updates a module to export a package 211 static jvmtiError add_module_exports(Handle module, Handle pkg_name, Handle to_module, TRAPS); 212 213 // Updates a module to open a package 214 static jvmtiError add_module_opens(Handle module, Handle pkg_name, Handle to_module, TRAPS); 215 216 // Add a used service to the module 217 static jvmtiError add_module_uses(Handle module, Handle service, TRAPS); 218 219 // Add a service provider to the module 220 static jvmtiError add_module_provides(Handle module, Handle service, Handle impl_class, TRAPS); 221 222 // let JVMTI know that the JVM_OnLoad code is running 223 static void enter_onload_phase() NOT_JVMTI_RETURN; 224 225 // let JVMTI know that the VM isn't up yet (and JVM_OnLoad code isn't running) 226 static void enter_primordial_phase() NOT_JVMTI_RETURN; 227 228 // let JVMTI know that the VM isn't up yet but JNI is live 229 static void enter_early_start_phase() NOT_JVMTI_RETURN; 230 static void enter_start_phase() NOT_JVMTI_RETURN; 231 232 // let JVMTI know that the VM is fully up and running now 233 static void enter_live_phase() NOT_JVMTI_RETURN; 234 235 // ------ can_* conditions (below) are set at OnLoad and never changed ------------ 236 inline static bool can_modify_any_class() { 237 JVMTI_ONLY(return _can_modify_any_class); 238 NOT_JVMTI(return false); 239 } 240 inline static bool can_access_local_variables() { 241 JVMTI_ONLY(return _can_access_local_variables); 242 NOT_JVMTI(return false); 243 } 244 inline static bool can_hotswap_or_post_breakpoint() { 245 JVMTI_ONLY(return _can_hotswap_or_post_breakpoint); 246 NOT_JVMTI(return false); 247 } 248 inline static bool can_walk_any_space() { 249 JVMTI_ONLY(return _can_walk_any_space); 250 NOT_JVMTI(return false); 251 } 252 253 // field access management 254 static address get_field_access_count_addr() NOT_JVMTI_RETURN_(0); 255 256 // field modification management 257 static address get_field_modification_count_addr() NOT_JVMTI_RETURN_(0); 258 259 // ----------------- 260 261 static bool is_jvmti_version(jint version) { 262 JVMTI_ONLY(return (version & JVMTI_VERSION_MASK) == JVMTI_VERSION_VALUE); 263 NOT_JVMTI(return false); 264 } 265 static bool is_jvmdi_version(jint version) { 266 JVMTI_ONLY(return (version & JVMTI_VERSION_MASK) == JVMDI_VERSION_VALUE); 267 NOT_JVMTI(return false); 268 } 269 static jint get_jvmti_interface(JavaVM *jvm, void **penv, jint version) NOT_JVMTI_RETURN_(0); 270 static void decode_version_values(jint version, int * major, int * minor, 271 int * micro) NOT_JVMTI_RETURN; 272 273 // single stepping management methods 274 static void at_single_stepping_point(JavaThread *thread, Method* method, address location) NOT_JVMTI_RETURN; 275 static void expose_single_stepping(JavaThread *thread) NOT_JVMTI_RETURN; 276 static bool hide_single_stepping(JavaThread *thread) NOT_JVMTI_RETURN_(false); 277 278 // Methods that notify the debugger that something interesting has happened in the VM. 279 static void post_early_vm_start () NOT_JVMTI_RETURN; 280 static void post_vm_start () NOT_JVMTI_RETURN; 281 static void post_vm_initialized () NOT_JVMTI_RETURN; 282 static void post_vm_death () NOT_JVMTI_RETURN; 283 284 static void post_single_step (JavaThread *thread, Method* method, address location) NOT_JVMTI_RETURN; 285 static void post_raw_breakpoint (JavaThread *thread, Method* method, address location) NOT_JVMTI_RETURN; 286 287 static void post_exception_throw (JavaThread *thread, Method* method, address location, oop exception) NOT_JVMTI_RETURN; 288 static void notice_unwind_due_to_exception (JavaThread *thread, Method* method, address location, oop exception, bool in_handler_frame) NOT_JVMTI_RETURN; 289 290 static oop jni_GetField_probe (JavaThread *thread, jobject jobj, 291 oop obj, Klass* klass, jfieldID fieldID, bool is_static) 292 NOT_JVMTI_RETURN_(NULL); 293 static oop jni_GetField_probe_nh (JavaThread *thread, jobject jobj, 294 oop obj, Klass* klass, jfieldID fieldID, bool is_static) 295 NOT_JVMTI_RETURN_(NULL); 296 static void post_field_access_by_jni (JavaThread *thread, oop obj, 297 Klass* klass, jfieldID fieldID, bool is_static) NOT_JVMTI_RETURN; 298 static void post_field_access (JavaThread *thread, Method* method, 299 address location, Klass* field_klass, Handle object, jfieldID field) NOT_JVMTI_RETURN; 300 static oop jni_SetField_probe (JavaThread *thread, jobject jobj, 301 oop obj, Klass* klass, jfieldID fieldID, bool is_static, char sig_type, 302 jvalue *value) NOT_JVMTI_RETURN_(NULL); 303 static oop jni_SetField_probe_nh (JavaThread *thread, jobject jobj, 304 oop obj, Klass* klass, jfieldID fieldID, bool is_static, char sig_type, 305 jvalue *value) NOT_JVMTI_RETURN_(NULL); 306 static void post_field_modification_by_jni(JavaThread *thread, oop obj, 307 Klass* klass, jfieldID fieldID, bool is_static, char sig_type, 308 jvalue *value); 309 static void post_raw_field_modification(JavaThread *thread, Method* method, 310 address location, Klass* field_klass, Handle object, jfieldID field, 311 char sig_type, jvalue *value) NOT_JVMTI_RETURN; 312 313 static void post_method_entry (JavaThread *thread, Method* method, frame current_frame) NOT_JVMTI_RETURN; 314 static void post_method_exit (JavaThread *thread, Method* method, frame current_frame) NOT_JVMTI_RETURN; 315 316 static void post_class_load (JavaThread *thread, Klass* klass) NOT_JVMTI_RETURN; 317 static void post_class_unload (Klass* klass) NOT_JVMTI_RETURN; 318 static void post_class_prepare (JavaThread *thread, Klass* klass) NOT_JVMTI_RETURN; 319 320 static void post_thread_start (JavaThread *thread) NOT_JVMTI_RETURN; 321 static void post_thread_end (JavaThread *thread) NOT_JVMTI_RETURN; 322 323 // Support for java.lang.instrument agent loading. 324 static bool _should_post_class_file_load_hook; 325 inline static void set_should_post_class_file_load_hook(bool on) { _should_post_class_file_load_hook = on; } 326 inline static bool should_post_class_file_load_hook() { 327 JVMTI_ONLY(return _should_post_class_file_load_hook); 328 NOT_JVMTI(return false;) 329 } 330 // Return true if the class was modified by the hook. 331 static bool post_class_file_load_hook(Symbol* h_name, Handle class_loader, 332 Handle h_protection_domain, 333 unsigned char **data_ptr, unsigned char **end_ptr, 334 JvmtiCachedClassFileData **cache_ptr) NOT_JVMTI_RETURN_(false); 335 static void post_native_method_bind(Method* method, address* function_ptr) NOT_JVMTI_RETURN; 336 static void post_compiled_method_load(nmethod *nm) NOT_JVMTI_RETURN; 337 static void post_dynamic_code_generated(const char *name, const void *code_begin, const void *code_end) NOT_JVMTI_RETURN; 338 339 // used to post a CompiledMethodUnload event 340 static void post_compiled_method_unload(jmethodID mid, const void *code_begin) NOT_JVMTI_RETURN; 341 342 // similiar to post_dynamic_code_generated except that it can be used to 343 // post a DynamicCodeGenerated event while holding locks in the VM. Any event 344 // posted using this function is recorded by the enclosing event collector 345 // -- JvmtiDynamicCodeEventCollector. 346 static void post_dynamic_code_generated_while_holding_locks(const char* name, address code_begin, address code_end) NOT_JVMTI_RETURN; 347 348 static void post_garbage_collection_finish() NOT_JVMTI_RETURN; 349 static void post_garbage_collection_start() NOT_JVMTI_RETURN; 350 static void post_data_dump() NOT_JVMTI_RETURN; 351 static void post_monitor_contended_enter(JavaThread *thread, ObjectMonitor *obj_mntr) NOT_JVMTI_RETURN; 352 static void post_monitor_contended_entered(JavaThread *thread, ObjectMonitor *obj_mntr) NOT_JVMTI_RETURN; 353 static void post_monitor_wait(JavaThread *thread, oop obj, jlong timeout) NOT_JVMTI_RETURN; 354 static void post_monitor_waited(JavaThread *thread, ObjectMonitor *obj_mntr, jboolean timed_out) NOT_JVMTI_RETURN; 355 static void post_object_free(JvmtiEnv* env, jlong tag) NOT_JVMTI_RETURN; 356 static void post_resource_exhausted(jint resource_exhausted_flags, const char* detail) NOT_JVMTI_RETURN; 357 static void record_vm_internal_object_allocation(oop object) NOT_JVMTI_RETURN; 358 // Post objects collected by vm_object_alloc_event_collector. 359 static void post_vm_object_alloc(JavaThread *thread, oop object) NOT_JVMTI_RETURN; 360 // Collects vm internal objects for later event posting. 361 inline static void vm_object_alloc_event_collector(oop object) { 362 if (should_post_vm_object_alloc()) { 363 record_vm_internal_object_allocation(object); 364 } 365 } 366 inline static void post_array_size_exhausted() { 367 if (should_post_resource_exhausted()) { 368 post_resource_exhausted(JVMTI_RESOURCE_EXHAUSTED_OOM_ERROR, 369 "Requested array size exceeds VM limit"); 370 } 371 } 372 373 static void cleanup_thread (JavaThread* thread) NOT_JVMTI_RETURN; 374 static void clear_detected_exception (JavaThread* thread) NOT_JVMTI_RETURN; 375 376 static void oops_do(OopClosure* f) NOT_JVMTI_RETURN; 377 static void weak_oops_do(BoolObjectClosure* b, OopClosure* f) NOT_JVMTI_RETURN; 378 static void gc_epilogue() NOT_JVMTI_RETURN; 379 380 static void transition_pending_onload_raw_monitors() NOT_JVMTI_RETURN; 381 382 #if INCLUDE_SERVICES 383 // attach support 384 static jint load_agent_library(const char *agent, const char *absParam, const char *options, outputStream* out) NOT_JVMTI_RETURN_(JNI_ERR); 385 #endif 386 387 // SetNativeMethodPrefix support 388 static char** get_all_native_method_prefixes(int* count_ptr) NOT_JVMTI_RETURN_(NULL); 389 390 // JavaThread lifecycle support: 391 static jvmtiError cv_external_thread_to_JavaThread(ThreadsList * t_list, 392 jthread thread, 393 JavaThread ** jt_pp, 394 oop * thread_oop_p); 395 static jvmtiError cv_oop_to_JavaThread(ThreadsList * t_list, oop thread_oop, 396 JavaThread ** jt_pp); 397 }; 398 399 // Support class used by JvmtiDynamicCodeEventCollector and others. It 400 // describes a single code blob by name and address range. 401 class JvmtiCodeBlobDesc : public CHeapObj<mtInternal> { 402 private: 403 char _name[64]; 404 address _code_begin; 405 address _code_end; 406 407 public: 408 JvmtiCodeBlobDesc(const char *name, address code_begin, address code_end) { 409 assert(name != NULL, "all code blobs must be named"); 410 strncpy(_name, name, sizeof(_name)); 411 _name[sizeof(_name)-1] = '\0'; 412 _code_begin = code_begin; 413 _code_end = code_end; 414 } 415 char* name() { return _name; } 416 address code_begin() { return _code_begin; } 417 address code_end() { return _code_end; } 418 }; 419 420 // JvmtiEventCollector is a helper class to setup thread for 421 // event collection. 422 class JvmtiEventCollector : public StackObj { 423 private: 424 JvmtiEventCollector* _prev; // Save previous one to support nested event collector. 425 426 public: 427 void setup_jvmti_thread_state(); // Set this collector in current thread. 428 void unset_jvmti_thread_state(); // Reset previous collector in current thread. 429 virtual bool is_dynamic_code_event() { return false; } 430 virtual bool is_vm_object_alloc_event(){ return false; } 431 JvmtiEventCollector *get_prev() { return _prev; } 432 }; 433 434 // A JvmtiDynamicCodeEventCollector is a helper class for the JvmtiExport 435 // interface. It collects "dynamic code generated" events that are posted 436 // while holding locks. When the event collector goes out of scope the 437 // events will be posted. 438 // 439 // Usage :- 440 // 441 // { 442 // JvmtiDynamicCodeEventCollector event_collector; 443 // : 444 // { MutexLocker ml(...) 445 // : 446 // JvmtiExport::post_dynamic_code_generated_while_holding_locks(...) 447 // } 448 // // event collector goes out of scope => post events to profiler. 449 // } 450 451 class JvmtiDynamicCodeEventCollector : public JvmtiEventCollector { 452 private: 453 GrowableArray<JvmtiCodeBlobDesc*>* _code_blobs; // collected code blob events 454 455 friend class JvmtiExport; 456 void register_stub(const char* name, address start, address end); 457 458 public: 459 JvmtiDynamicCodeEventCollector() NOT_JVMTI_RETURN; 460 ~JvmtiDynamicCodeEventCollector() NOT_JVMTI_RETURN; 461 bool is_dynamic_code_event() { return true; } 462 463 }; 464 465 // Used to record vm internally allocated object oops and post 466 // vm object alloc event for objects visible to java world. 467 // Constructor enables JvmtiThreadState flag and all vm allocated 468 // objects are recorded in a growable array. When destructor is 469 // called the vm object alloc event is posted for each objects 470 // visible to java world. 471 // See jvm.cpp file for its usage. 472 // 473 class JvmtiVMObjectAllocEventCollector : public JvmtiEventCollector { 474 private: 475 GrowableArray<oop>* _allocated; // field to record vm internally allocated object oop. 476 bool _enable; // This flag is enabled in constructor and disabled 477 // in destructor before posting event. To avoid 478 // collection of objects allocated while running java code inside 479 // agent post_vm_object_alloc() event handler. 480 481 //GC support 482 void oops_do(OopClosure* f); 483 484 friend class JvmtiExport; 485 // Record vm allocated object oop. 486 inline void record_allocation(oop obj); 487 488 //GC support 489 static void oops_do_for_all_threads(OopClosure* f); 490 491 public: 492 JvmtiVMObjectAllocEventCollector() NOT_JVMTI_RETURN; 493 ~JvmtiVMObjectAllocEventCollector() NOT_JVMTI_RETURN; 494 bool is_vm_object_alloc_event() { return true; } 495 496 bool is_enabled() { return _enable; } 497 void set_enabled(bool on) { _enable = on; } 498 }; 499 500 501 502 // Marker class to disable the posting of VMObjectAlloc events 503 // within its scope. 504 // 505 // Usage :- 506 // 507 // { 508 // NoJvmtiVMObjectAllocMark njm; 509 // : 510 // // VMObjAlloc event will not be posted 511 // JvmtiExport::vm_object_alloc_event_collector(obj); 512 // : 513 // } 514 515 class NoJvmtiVMObjectAllocMark : public StackObj { 516 private: 517 // enclosing collector if enabled, NULL otherwise 518 JvmtiVMObjectAllocEventCollector *_collector; 519 520 bool was_enabled() { return _collector != NULL; } 521 522 public: 523 NoJvmtiVMObjectAllocMark() NOT_JVMTI_RETURN; 524 ~NoJvmtiVMObjectAllocMark() NOT_JVMTI_RETURN; 525 }; 526 527 528 // Base class for reporting GC events to JVMTI. 529 class JvmtiGCMarker : public StackObj { 530 public: 531 JvmtiGCMarker() NOT_JVMTI_RETURN; 532 ~JvmtiGCMarker() NOT_JVMTI_RETURN; 533 }; 534 535 // JvmtiHideSingleStepping is a helper class for hiding 536 // internal single step events. 537 class JvmtiHideSingleStepping : public StackObj { 538 private: 539 bool _single_step_hidden; 540 JavaThread * _thread; 541 542 public: 543 JvmtiHideSingleStepping(JavaThread * thread) { 544 assert(thread != NULL, "sanity check"); 545 546 _single_step_hidden = false; 547 _thread = thread; 548 if (JvmtiExport::should_post_single_step()) { 549 _single_step_hidden = JvmtiExport::hide_single_stepping(_thread); 550 } 551 } 552 553 ~JvmtiHideSingleStepping() { 554 if (_single_step_hidden) { 555 JvmtiExport::expose_single_stepping(_thread); 556 } 557 } 558 }; 559 560 #endif // SHARE_VM_PRIMS_JVMTIEXPORT_HPP