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 JVMTI_SUPPORT_FLAG(should_post_sampled_object_alloc)
127
128 // If flag cannot be implemented, give an error if on=true
129 static void report_unsupported(bool on);
130
131 // these should only be called by the friend class
132 friend class JvmtiManageCapabilities;
133 inline static void set_can_modify_any_class(bool on) {
134 JVMTI_ONLY(_can_modify_any_class = (on != 0);)
135 }
136 inline static void set_can_access_local_variables(bool on) {
137 JVMTI_ONLY(_can_access_local_variables = (on != 0);)
138 }
139 inline static void set_can_hotswap_or_post_breakpoint(bool on) {
140 JVMTI_ONLY(_can_hotswap_or_post_breakpoint = (on != 0);)
141 }
142 inline static void set_can_walk_any_space(bool on) {
143 JVMTI_ONLY(_can_walk_any_space = (on != 0);)
144 }
145
146 enum {
147 JVMTI_VERSION_MASK = 0x70000000,
148 JVMTI_VERSION_VALUE = 0x30000000,
149 JVMDI_VERSION_VALUE = 0x20000000
150 };
151
152 static void post_field_modification(JavaThread *thread, Method* method, address location,
153 Klass* field_klass, Handle object, jfieldID field,
154 char sig_type, jvalue *value);
155
156
157 // posts a DynamicCodeGenerated event (internal/private implementation).
158 // The public post_dynamic_code_generated* functions make use of the
159 // internal implementation. Also called from JvmtiDeferredEvent::post()
160 static void post_dynamic_code_generated_internal(const char *name, const void *code_begin, const void *code_end) NOT_JVMTI_RETURN;
161
162 private:
163
164 // GenerateEvents support to allow posting of CompiledMethodLoad and
165 // DynamicCodeGenerated events for a given environment.
166 friend class JvmtiCodeBlobEvents;
167
168 static void post_compiled_method_load(JvmtiEnv* env, const jmethodID method, const jint length,
169 const void *code_begin, const jint map_length,
170 const jvmtiAddrLocationMap* map) NOT_JVMTI_RETURN;
171 static void post_dynamic_code_generated(JvmtiEnv* env, const char *name, const void *code_begin,
172 const void *code_end) NOT_JVMTI_RETURN;
173
174 // The RedefineClasses() API breaks some invariants in the "regular"
175 // system. For example, there are sanity checks when GC'ing nmethods
176 // that require the containing class to be unloading. However, when a
177 // method is redefined, the old method and nmethod can become GC'able
178 // without the containing class unloading. The state of becoming
179 // GC'able can be asynchronous to the RedefineClasses() call since
180 // the old method may still be running and cannot be GC'ed until
181 // after all old invocations have finished. Additionally, a method
182 // that has not been redefined may have an nmethod that depends on
183 // the redefined method. The dependent nmethod will get deopted in
184 // this case and may also be GC'able without the containing class
185 // being unloaded.
186 //
187 // This flag indicates whether RedefineClasses() has ever redefined
188 // one or more classes during the lifetime of the VM. The flag should
189 // only be set by the friend class and can be queried by other sub
190 // systems as needed to relax invariant checks.
191 static bool _has_redefined_a_class;
192 friend class VM_RedefineClasses;
193 inline static void set_has_redefined_a_class() {
194 JVMTI_ONLY(_has_redefined_a_class = true;)
195 }
196 // Flag to indicate if the compiler has recorded all dependencies. When the
197 // can_redefine_classes capability is enabled in the OnLoad phase then the compiler
198 // records all dependencies from startup. However if the capability is first
199 // enabled some time later then the dependencies recorded by the compiler
200 // are incomplete. This flag is used by RedefineClasses to know if the
201 // dependency information is complete or not.
202 static bool _all_dependencies_are_recorded;
203
204 public:
205 inline static bool has_redefined_a_class() {
206 JVMTI_ONLY(return _has_redefined_a_class);
207 NOT_JVMTI(return false);
208 }
209
210 inline static bool all_dependencies_are_recorded() {
211 return _all_dependencies_are_recorded;
212 }
213
214 inline static void set_all_dependencies_are_recorded(bool on) {
215 _all_dependencies_are_recorded = (on != 0);
216 }
217
218 // Add read edges to the unnamed modules of the bootstrap and app class loaders
219 static void add_default_read_edges(Handle h_module, TRAPS) NOT_JVMTI_RETURN;
220
221 // Add a read edge to the module
222 static jvmtiError add_module_reads(Handle module, Handle to_module, TRAPS);
223
224 // Updates a module to export a package
225 static jvmtiError add_module_exports(Handle module, Handle pkg_name, Handle to_module, TRAPS);
226
227 // Updates a module to open a package
228 static jvmtiError add_module_opens(Handle module, Handle pkg_name, Handle to_module, TRAPS);
229
230 // Add a used service to the module
231 static jvmtiError add_module_uses(Handle module, Handle service, TRAPS);
232
233 // Add a service provider to the module
234 static jvmtiError add_module_provides(Handle module, Handle service, Handle impl_class, TRAPS);
235
236 // let JVMTI know that the JVM_OnLoad code is running
237 static void enter_onload_phase() NOT_JVMTI_RETURN;
238
239 // let JVMTI know that the VM isn't up yet (and JVM_OnLoad code isn't running)
240 static void enter_primordial_phase() NOT_JVMTI_RETURN;
241
242 // let JVMTI know that the VM isn't up yet but JNI is live
243 static void enter_early_start_phase() NOT_JVMTI_RETURN;
244 static void enter_start_phase() NOT_JVMTI_RETURN;
245
246 // let JVMTI know that the VM is fully up and running now
247 static void enter_live_phase() NOT_JVMTI_RETURN;
248
249 // ------ can_* conditions (below) are set at OnLoad and never changed ------------
250 inline static bool can_modify_any_class() {
251 JVMTI_ONLY(return _can_modify_any_class);
252 NOT_JVMTI(return false);
253 }
254 inline static bool can_access_local_variables() {
255 JVMTI_ONLY(return _can_access_local_variables);
256 NOT_JVMTI(return false);
257 }
258 inline static bool can_hotswap_or_post_breakpoint() {
259 JVMTI_ONLY(return _can_hotswap_or_post_breakpoint);
260 NOT_JVMTI(return false);
261 }
262 inline static bool can_walk_any_space() {
263 JVMTI_ONLY(return _can_walk_any_space);
264 NOT_JVMTI(return false);
265 }
266
267 // field access management
268 static address get_field_access_count_addr() NOT_JVMTI_RETURN_(0);
269
270 // field modification management
271 static address get_field_modification_count_addr() NOT_JVMTI_RETURN_(0);
272
273 // -----------------
274
275 static bool is_jvmti_version(jint version) {
276 JVMTI_ONLY(return (version & JVMTI_VERSION_MASK) == JVMTI_VERSION_VALUE);
277 NOT_JVMTI(return false);
278 }
279 static bool is_jvmdi_version(jint version) {
280 JVMTI_ONLY(return (version & JVMTI_VERSION_MASK) == JVMDI_VERSION_VALUE);
281 NOT_JVMTI(return false);
282 }
283 static jint get_jvmti_interface(JavaVM *jvm, void **penv, jint version) NOT_JVMTI_RETURN_(0);
284 static void decode_version_values(jint version, int * major, int * minor,
285 int * micro) NOT_JVMTI_RETURN;
286
287 // single stepping management methods
288 static void at_single_stepping_point(JavaThread *thread, Method* method, address location) NOT_JVMTI_RETURN;
289 static void expose_single_stepping(JavaThread *thread) NOT_JVMTI_RETURN;
290 static bool hide_single_stepping(JavaThread *thread) NOT_JVMTI_RETURN_(false);
291
292 // Methods that notify the debugger that something interesting has happened in the VM.
293 static void post_early_vm_start () NOT_JVMTI_RETURN;
294 static void post_vm_start () NOT_JVMTI_RETURN;
295 static void post_vm_initialized () NOT_JVMTI_RETURN;
296 static void post_vm_death () NOT_JVMTI_RETURN;
297
298 static void post_single_step (JavaThread *thread, Method* method, address location) NOT_JVMTI_RETURN;
299 static void post_raw_breakpoint (JavaThread *thread, Method* method, address location) NOT_JVMTI_RETURN;
300
301 static void post_exception_throw (JavaThread *thread, Method* method, address location, oop exception) NOT_JVMTI_RETURN;
302 static void notice_unwind_due_to_exception (JavaThread *thread, Method* method, address location, oop exception, bool in_handler_frame) NOT_JVMTI_RETURN;
303
304 static oop jni_GetField_probe (JavaThread *thread, jobject jobj,
305 oop obj, Klass* klass, jfieldID fieldID, bool is_static)
306 NOT_JVMTI_RETURN_(NULL);
307 static oop jni_GetField_probe_nh (JavaThread *thread, jobject jobj,
308 oop obj, Klass* klass, jfieldID fieldID, bool is_static)
309 NOT_JVMTI_RETURN_(NULL);
310 static void post_field_access_by_jni (JavaThread *thread, oop obj,
311 Klass* klass, jfieldID fieldID, bool is_static) NOT_JVMTI_RETURN;
312 static void post_field_access (JavaThread *thread, Method* method,
313 address location, Klass* field_klass, Handle object, jfieldID field) NOT_JVMTI_RETURN;
314 static oop jni_SetField_probe (JavaThread *thread, jobject jobj,
315 oop obj, Klass* klass, jfieldID fieldID, bool is_static, char sig_type,
316 jvalue *value) NOT_JVMTI_RETURN_(NULL);
317 static oop jni_SetField_probe_nh (JavaThread *thread, jobject jobj,
318 oop obj, Klass* klass, jfieldID fieldID, bool is_static, char sig_type,
319 jvalue *value) NOT_JVMTI_RETURN_(NULL);
320 static void post_field_modification_by_jni(JavaThread *thread, oop obj,
321 Klass* klass, jfieldID fieldID, bool is_static, char sig_type,
322 jvalue *value);
323 static void post_raw_field_modification(JavaThread *thread, Method* method,
324 address location, Klass* field_klass, Handle object, jfieldID field,
325 char sig_type, jvalue *value) NOT_JVMTI_RETURN;
326
327 static void post_method_entry (JavaThread *thread, Method* method, frame current_frame) NOT_JVMTI_RETURN;
328 static void post_method_exit (JavaThread *thread, Method* method, frame current_frame) NOT_JVMTI_RETURN;
329
330 static void post_class_load (JavaThread *thread, Klass* klass) NOT_JVMTI_RETURN;
331 static void post_class_unload (Klass* klass) NOT_JVMTI_RETURN;
332 static void post_class_prepare (JavaThread *thread, Klass* klass) NOT_JVMTI_RETURN;
333
334 static void post_thread_start (JavaThread *thread) NOT_JVMTI_RETURN;
335 static void post_thread_end (JavaThread *thread) NOT_JVMTI_RETURN;
336
337 // Support for java.lang.instrument agent loading.
338 static bool _should_post_class_file_load_hook;
339 inline static void set_should_post_class_file_load_hook(bool on) { _should_post_class_file_load_hook = on; }
340 inline static bool should_post_class_file_load_hook() {
341 JVMTI_ONLY(return _should_post_class_file_load_hook);
342 NOT_JVMTI(return false;)
343 }
344 // Return true if the class was modified by the hook.
345 static bool post_class_file_load_hook(Symbol* h_name, Handle class_loader,
346 Handle h_protection_domain,
347 unsigned char **data_ptr, unsigned char **end_ptr,
348 JvmtiCachedClassFileData **cache_ptr) NOT_JVMTI_RETURN_(false);
349 static void post_native_method_bind(Method* method, address* function_ptr) NOT_JVMTI_RETURN;
350 static void post_compiled_method_load(nmethod *nm) NOT_JVMTI_RETURN;
351 static void post_dynamic_code_generated(const char *name, const void *code_begin, const void *code_end) NOT_JVMTI_RETURN;
352
353 // used to post a CompiledMethodUnload event
354 static void post_compiled_method_unload(jmethodID mid, const void *code_begin) NOT_JVMTI_RETURN;
355
356 // similiar to post_dynamic_code_generated except that it can be used to
357 // post a DynamicCodeGenerated event while holding locks in the VM. Any event
358 // posted using this function is recorded by the enclosing event collector
359 // -- JvmtiDynamicCodeEventCollector.
360 static void post_dynamic_code_generated_while_holding_locks(const char* name, address code_begin, address code_end) NOT_JVMTI_RETURN;
361
362 static void post_garbage_collection_finish() NOT_JVMTI_RETURN;
363 static void post_garbage_collection_start() NOT_JVMTI_RETURN;
364 static void post_data_dump() NOT_JVMTI_RETURN;
365 static void post_monitor_contended_enter(JavaThread *thread, ObjectMonitor *obj_mntr) NOT_JVMTI_RETURN;
366 static void post_monitor_contended_entered(JavaThread *thread, ObjectMonitor *obj_mntr) NOT_JVMTI_RETURN;
367 static void post_monitor_wait(JavaThread *thread, oop obj, jlong timeout) NOT_JVMTI_RETURN;
368 static void post_monitor_waited(JavaThread *thread, ObjectMonitor *obj_mntr, jboolean timed_out) NOT_JVMTI_RETURN;
369 static void post_object_free(JvmtiEnv* env, jlong tag) NOT_JVMTI_RETURN;
370 static void post_resource_exhausted(jint resource_exhausted_flags, const char* detail) NOT_JVMTI_RETURN;
371 static void record_vm_internal_object_allocation(oop object) NOT_JVMTI_RETURN;
372 // Post objects collected by vm_object_alloc_event_collector.
373 static void post_vm_object_alloc(JavaThread *thread, oop object) NOT_JVMTI_RETURN;
374 // Collects vm internal objects for later event posting.
375 inline static void vm_object_alloc_event_collector(oop object) {
376 if (should_post_vm_object_alloc()) {
377 record_vm_internal_object_allocation(object);
378 }
379 }
380
381 static void record_sampled_internal_object_allocation(oop object) NOT_JVMTI_RETURN;
382 // Post objects collected by sampled_object_alloc_event_collector.
383 static void post_sampled_object_alloc(JavaThread *thread, oop object) NOT_JVMTI_RETURN;
384 // Collects vm internal objects for later event posting.
385 inline static void sampled_object_alloc_event_collector(oop object) {
386 if (should_post_sampled_object_alloc()) {
387 record_sampled_internal_object_allocation(object);
388 }
389 }
390
391 inline static void post_array_size_exhausted() {
392 if (should_post_resource_exhausted()) {
393 post_resource_exhausted(JVMTI_RESOURCE_EXHAUSTED_OOM_ERROR,
394 "Requested array size exceeds VM limit");
395 }
396 }
397
398 static void cleanup_thread (JavaThread* thread) NOT_JVMTI_RETURN;
399 static void clear_detected_exception (JavaThread* thread) NOT_JVMTI_RETURN;
400
401 static void oops_do(OopClosure* f) NOT_JVMTI_RETURN;
402 static void weak_oops_do(BoolObjectClosure* b, OopClosure* f) NOT_JVMTI_RETURN;
403 static void gc_epilogue() NOT_JVMTI_RETURN;
404
405 static void transition_pending_onload_raw_monitors() NOT_JVMTI_RETURN;
406
407 #if INCLUDE_SERVICES
408 // attach support
409 static jint load_agent_library(const char *agent, const char *absParam, const char *options, outputStream* out) NOT_JVMTI_RETURN_(JNI_ERR);
410 #endif
411
412 // SetNativeMethodPrefix support
413 static char** get_all_native_method_prefixes(int* count_ptr) NOT_JVMTI_RETURN_(NULL);
414
415 // JavaThread lifecycle support:
416 static jvmtiError cv_external_thread_to_JavaThread(ThreadsList * t_list,
417 jthread thread,
418 JavaThread ** jt_pp,
419 oop * thread_oop_p);
420 static jvmtiError cv_oop_to_JavaThread(ThreadsList * t_list, oop thread_oop,
421 JavaThread ** jt_pp);
422 };
423
424 // Support class used by JvmtiDynamicCodeEventCollector and others. It
425 // describes a single code blob by name and address range.
426 class JvmtiCodeBlobDesc : public CHeapObj<mtInternal> {
427 private:
428 char _name[64];
429 address _code_begin;
430 address _code_end;
431
432 public:
433 JvmtiCodeBlobDesc(const char *name, address code_begin, address code_end) {
434 assert(name != NULL, "all code blobs must be named");
435 strncpy(_name, name, sizeof(_name));
436 _name[sizeof(_name)-1] = '\0';
437 _code_begin = code_begin;
438 _code_end = code_end;
439 }
440 char* name() { return _name; }
441 address code_begin() { return _code_begin; }
442 address code_end() { return _code_end; }
443 };
444
445 // JvmtiEventCollector is a helper class to setup thread for
446 // event collection.
447 class JvmtiEventCollector : public StackObj {
448 private:
449 JvmtiEventCollector* _prev; // Save previous one to support nested event collector.
450
451 public:
452 JvmtiEventCollector() : _prev(NULL) {}
453
454 void setup_jvmti_thread_state(); // Set this collector in current thread.
455 void unset_jvmti_thread_state(); // Reset previous collector in current thread.
456 virtual bool is_dynamic_code_event() { return false; }
457 virtual bool is_vm_object_alloc_event(){ return false; }
458 virtual bool is_sampled_object_alloc_event(){ return false; }
459 JvmtiEventCollector *get_prev() { return _prev; }
460 };
461
462 // A JvmtiDynamicCodeEventCollector is a helper class for the JvmtiExport
463 // interface. It collects "dynamic code generated" events that are posted
464 // while holding locks. When the event collector goes out of scope the
465 // events will be posted.
466 //
467 // Usage :-
468 //
469 // {
470 // JvmtiDynamicCodeEventCollector event_collector;
471 // :
472 // { MutexLocker ml(...)
473 // :
474 // JvmtiExport::post_dynamic_code_generated_while_holding_locks(...)
475 // }
476 // // event collector goes out of scope => post events to profiler.
477 // }
478
479 class JvmtiDynamicCodeEventCollector : public JvmtiEventCollector {
480 private:
481 GrowableArray<JvmtiCodeBlobDesc*>* _code_blobs; // collected code blob events
482
483 friend class JvmtiExport;
484 void register_stub(const char* name, address start, address end);
485
486 public:
487 JvmtiDynamicCodeEventCollector() NOT_JVMTI_RETURN;
488 ~JvmtiDynamicCodeEventCollector() NOT_JVMTI_RETURN;
489 bool is_dynamic_code_event() { return true; }
490
491 };
492
493 // Used as a base class for object allocation collection and then posting
494 // the allocations to any event notification callbacks.
495 //
496 class JvmtiObjectAllocEventCollector : public JvmtiEventCollector {
497 protected:
498 GrowableArray<oop>* _allocated; // field to record vm internally allocated object oop.
499 bool _enable; // This flag is enabled in constructor and disabled
500 // in destructor before posting event. To avoid
501 // collection of objects allocated while running java code inside
502 // agent post_X_object_alloc() event handler.
503 void (*_post_callback)(JavaThread*, oop); // what callback to use when destroying the collector.
504 bool _callback_for_all_oops;
505
506 //GC support
507 void oops_do(OopClosure* f);
508
509 friend class JvmtiExport;
510 // Record vm allocated object oop.
511 inline void record_allocation(oop obj);
512
513 //GC support
514 static void oops_do_for_all_threads(OopClosure* f);
515
516 public:
517 JvmtiObjectAllocEventCollector() NOT_JVMTI_RETURN;
518
519 void generate_call_for_allocated();
520
521 bool is_enabled() { return _enable; }
522 void set_enabled(bool on) { _enable = on; }
523 };
524
525 // Used to record vm internally allocated object oops and post
526 // vm object alloc event for objects visible to java world.
527 // Constructor enables JvmtiThreadState flag and all vm allocated
528 // objects are recorded in a growable array. When destructor is
529 // called the vm object alloc event is posted for each object
530 // visible to java world.
531 // See jvm.cpp file for its usage.
532 //
533 class JvmtiVMObjectAllocEventCollector : public JvmtiObjectAllocEventCollector {
534 public:
535 JvmtiVMObjectAllocEventCollector() NOT_JVMTI_RETURN;
536 ~JvmtiVMObjectAllocEventCollector() NOT_JVMTI_RETURN;
537 virtual bool is_vm_object_alloc_event() { return true; }
538 };
539
540 // Used to record sampled allocated object oops and post
541 // sampled object alloc event.
542 // Constructor enables JvmtiThreadState flag and all sampled allocated
543 // objects are recorded in a growable array. When destructor is
544 // called the sampled object alloc event is posted for each sampled object.
545 // See jvm.cpp file for its usage.
546 //
547 class JvmtiSampledObjectAllocEventCollector : public JvmtiObjectAllocEventCollector {
548 public:
549 JvmtiSampledObjectAllocEventCollector() NOT_JVMTI_RETURN;
550 ~JvmtiSampledObjectAllocEventCollector() NOT_JVMTI_RETURN;
551 bool is_sampled_object_alloc_event() { return true; }
552 };
553
554 // Marker class to disable the posting of VMObjectAlloc events
555 // within its scope.
556 //
557 // Usage :-
558 //
559 // {
560 // NoJvmtiVMObjectAllocMark njm;
561 // :
562 // // VMObjAlloc event will not be posted
563 // JvmtiExport::vm_object_alloc_event_collector(obj);
564 // :
565 // }
566
567 class NoJvmtiVMObjectAllocMark : public StackObj {
568 private:
569 // enclosing collector if enabled, NULL otherwise
570 JvmtiVMObjectAllocEventCollector *_collector;
571
572 bool was_enabled() { return _collector != NULL; }
573
574 public:
575 NoJvmtiVMObjectAllocMark() NOT_JVMTI_RETURN;
576 ~NoJvmtiVMObjectAllocMark() NOT_JVMTI_RETURN;
577 };
578
579
580 // Base class for reporting GC events to JVMTI.
581 class JvmtiGCMarker : public StackObj {
582 public:
583 JvmtiGCMarker() NOT_JVMTI_RETURN;
584 ~JvmtiGCMarker() NOT_JVMTI_RETURN;
585 };
586
587 // JvmtiHideSingleStepping is a helper class for hiding
588 // internal single step events.
589 class JvmtiHideSingleStepping : public StackObj {
590 private:
591 bool _single_step_hidden;
592 JavaThread * _thread;
593
594 public:
595 JvmtiHideSingleStepping(JavaThread * thread) {
596 assert(thread != NULL, "sanity check");
597
598 _single_step_hidden = false;
599 _thread = thread;
600 if (JvmtiExport::should_post_single_step()) {
601 _single_step_hidden = JvmtiExport::hide_single_stepping(_thread);
602 }
603 }
604
605 ~JvmtiHideSingleStepping() {
606 if (_single_step_hidden) {
607 JvmtiExport::expose_single_stepping(_thread);
608 }
609 }
610 };
611
612 #endif // SHARE_VM_PRIMS_JVMTIEXPORT_HPP