1 /*
2 * Copyright (c) 1998, 2026, 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_PRIMS_JVMTIEXPORT_HPP
26 #define SHARE_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/oopHandle.hpp"
33 #include "oops/oopsHierarchy.hpp"
34 #include "runtime/frame.hpp"
35 #include "runtime/handles.hpp"
36 #include "utilities/globalDefinitions.hpp"
37 #include "utilities/growableArray.hpp"
38 #include "utilities/macros.hpp"
39
40 // Must be included after jvmti.h.
41 #include "jvmticmlr.h"
42
43 // Forward declarations
44
45 struct JvmtiCachedClassFileData;
46 class JvmtiEventControllerPrivate;
47 class JvmtiManageCapabilities;
48 class JvmtiEnv;
49 class JvmtiThreadState;
50 class OopStorage;
51 class ThreadsList;
52
53 #define JVMTI_SUPPORT_FLAG(key) \
54 private: \
55 static bool _##key; \
56 public: \
57 inline static void set_##key(bool on) { \
58 JVMTI_ONLY(_##key = (on != 0)); \
59 NOT_JVMTI(report_unsupported(on)); \
60 } \
61 inline static bool key() { \
62 JVMTI_ONLY(return _##key); \
63 NOT_JVMTI(return false); \
64 }
65
66
67 // This class contains the JVMTI interface for the rest of hotspot.
68 //
69 class JvmtiExport : public AllStatic {
70 friend class VMStructs;
71 friend class CompileReplay;
72
73 private:
74
75 #if INCLUDE_JVMTI
76 static int _field_access_count;
77 static int _field_modification_count;
78
79 static bool _can_access_local_variables;
80 static bool _can_hotswap_or_post_breakpoint;
81 static bool _can_modify_any_class;
82 static bool _can_walk_any_space;
83 #endif // INCLUDE_JVMTI
84
85 JVMTI_SUPPORT_FLAG(can_get_source_debug_extension)
86 JVMTI_SUPPORT_FLAG(can_maintain_original_method_order)
87 JVMTI_SUPPORT_FLAG(can_post_interpreter_events)
88 JVMTI_SUPPORT_FLAG(can_post_on_exceptions)
89 JVMTI_SUPPORT_FLAG(can_post_breakpoint)
90 JVMTI_SUPPORT_FLAG(can_post_field_access)
91 JVMTI_SUPPORT_FLAG(can_post_field_modification)
92 JVMTI_SUPPORT_FLAG(can_post_method_entry)
93 JVMTI_SUPPORT_FLAG(can_post_method_exit)
94 JVMTI_SUPPORT_FLAG(can_post_frame_pop)
95 JVMTI_SUPPORT_FLAG(can_pop_frame)
96 JVMTI_SUPPORT_FLAG(can_force_early_return)
97 JVMTI_SUPPORT_FLAG(can_support_virtual_threads)
98 JVMTI_SUPPORT_FLAG(can_support_value_objects)
99
100 JVMTI_SUPPORT_FLAG(early_vmstart_recorded)
101 JVMTI_SUPPORT_FLAG(can_get_owned_monitor_info) // includes can_get_owned_monitor_stack_depth_info
102
103 friend class JvmtiEventControllerPrivate; // should only modify these flags
104 JVMTI_SUPPORT_FLAG(should_post_single_step)
105 JVMTI_SUPPORT_FLAG(should_post_field_access)
106 JVMTI_SUPPORT_FLAG(should_post_field_modification)
107 JVMTI_SUPPORT_FLAG(should_post_class_load)
108 JVMTI_SUPPORT_FLAG(should_post_class_prepare)
109 JVMTI_SUPPORT_FLAG(should_post_class_unload)
110 JVMTI_SUPPORT_FLAG(should_post_native_method_bind)
111 JVMTI_SUPPORT_FLAG(should_post_compiled_method_load)
112 JVMTI_SUPPORT_FLAG(should_post_compiled_method_unload)
113 JVMTI_SUPPORT_FLAG(should_post_dynamic_code_generated)
114 JVMTI_SUPPORT_FLAG(should_post_monitor_contended_enter)
115 JVMTI_SUPPORT_FLAG(should_post_monitor_contended_entered)
116 JVMTI_SUPPORT_FLAG(should_post_monitor_wait)
117 JVMTI_SUPPORT_FLAG(should_post_monitor_waited)
118 JVMTI_SUPPORT_FLAG(should_post_data_dump)
119 JVMTI_SUPPORT_FLAG(should_post_garbage_collection_start)
120 JVMTI_SUPPORT_FLAG(should_post_garbage_collection_finish)
121 JVMTI_SUPPORT_FLAG(should_post_on_exceptions)
122
123 // ------ the below maybe don't have to be (but are for now)
124 // fixed conditions here ------------
125 // any events can be enabled
126 JVMTI_SUPPORT_FLAG(should_post_thread_life)
127 JVMTI_SUPPORT_FLAG(should_post_object_free)
128 JVMTI_SUPPORT_FLAG(should_post_resource_exhausted)
129
130 // we are holding objects on the heap - need to talk to GC - e.g.
131 // breakpoint info
132 JVMTI_SUPPORT_FLAG(should_clean_up_heap_objects)
133 JVMTI_SUPPORT_FLAG(should_post_vm_object_alloc)
134 JVMTI_SUPPORT_FLAG(should_post_sampled_object_alloc)
135
136 JVMTI_SUPPORT_FLAG(should_post_vthread_start)
137 JVMTI_SUPPORT_FLAG(should_post_vthread_end)
138 JVMTI_SUPPORT_FLAG(should_post_vthread_mount)
139 JVMTI_SUPPORT_FLAG(should_post_vthread_unmount)
140
141 // If flag cannot be implemented, give an error if on=true
142 static void report_unsupported(bool on);
143
144 // these should only be called by the friend class
145 friend class JvmtiManageCapabilities;
146 inline static void set_can_modify_any_class(bool on) {
147 JVMTI_ONLY(_can_modify_any_class = (on != 0);)
148 }
149 inline static void set_can_access_local_variables(bool on) {
150 JVMTI_ONLY(_can_access_local_variables = (on != 0);)
151 }
152 inline static void set_can_hotswap_or_post_breakpoint(bool on) {
153 #if INCLUDE_JVMTI
154 // Check that _can_hotswap_or_post_breakpoint is not reset once it
155 // was set to true. When _can_hotswap_or_post_breakpoint is set to true
156 // _all_dependencies_are_recorded is also set to true and never
157 // reset so we have to ensure that evol dependencies are always
158 // recorded from that point on.
159 assert(!_can_hotswap_or_post_breakpoint || on, "sanity check");
160 _can_hotswap_or_post_breakpoint = (on != 0);
161 #endif
162 }
163 inline static void set_can_walk_any_space(bool on) {
164 JVMTI_ONLY(_can_walk_any_space = (on != 0);)
165 }
166
167 enum {
168 JVMTI_VERSION_MASK = 0x70000000,
169 JVMTI_VERSION_VALUE = 0x30000000,
170 JVMDI_VERSION_VALUE = 0x20000000
171 };
172
173 static void post_field_modification(JavaThread *thread, Method* method, address location,
174 Klass* field_klass, Handle object, jfieldID field,
175 char sig_type, jvalue *value);
176
177
178 // posts a DynamicCodeGenerated event (internal/private implementation).
179 // The public post_dynamic_code_generated* functions make use of the
180 // internal implementation. Also called from JvmtiDeferredEvent::post()
181 static void post_dynamic_code_generated_internal(const char *name, const void *code_begin, const void *code_end) NOT_JVMTI_RETURN;
182
183 static void post_class_unload_internal(const char *name) NOT_JVMTI_RETURN;
184
185 static void initialize_oop_storage() NOT_JVMTI_RETURN;
186 static OopStorage* jvmti_oop_storage();
187 static OopStorage* weak_tag_storage();
188 private:
189
190 // GenerateEvents support to allow posting of CompiledMethodLoad and
191 // DynamicCodeGenerated events for a given environment.
192 friend class JvmtiCodeBlobEvents;
193
194 static void post_dynamic_code_generated(JvmtiEnv* env, const char *name, const void *code_begin,
195 const void *code_end) NOT_JVMTI_RETURN;
196
197 // This flag indicates whether RedefineClasses() has ever redefined
198 // one or more classes during the lifetime of the VM. The flag should
199 // only be set by the friend class and can be queried by other sub
200 // systems as needed to relax invariant checks.
201 static uint64_t _redefinition_count;
202 friend class VM_RedefineClasses;
203 inline static void increment_redefinition_count() {
204 JVMTI_ONLY(_redefinition_count++;)
205 }
206 // Flag to indicate if the compiler has recorded all dependencies. When the
207 // can_redefine_classes capability is enabled in the OnLoad phase then the compiler
208 // records all dependencies from startup. However if the capability is first
209 // enabled some time later then the dependencies recorded by the compiler
210 // are incomplete. This flag is used by RedefineClasses to know if the
211 // dependency information is complete or not.
212 static bool _all_dependencies_are_recorded;
213
214 static void post_method_exit_inner(JavaThread* thread,
215 methodHandle& mh,
216 JvmtiThreadState *state,
217 bool exception_exit,
218 frame current_frame,
219 jvalue& value);
220
221 public:
222 inline static bool has_redefined_a_class() {
223 JVMTI_ONLY(return _redefinition_count != 0);
224 NOT_JVMTI(return false);
225 }
226
227 // Only set in safepoint, so no memory ordering needed.
228 inline static uint64_t redefinition_count() {
229 JVMTI_ONLY(return _redefinition_count);
230 NOT_JVMTI(return 0);
231 }
232
233 inline static bool all_dependencies_are_recorded() {
234 return _all_dependencies_are_recorded;
235 }
236
237 inline static void set_all_dependencies_are_recorded(bool on) {
238 _all_dependencies_are_recorded = (on != 0);
239 }
240
241 // Add read edges to the unnamed modules of the bootstrap and app class loaders
242 static void add_default_read_edges(Handle h_module, TRAPS) NOT_JVMTI_RETURN;
243
244 // Add a read edge to the module
245 static jvmtiError add_module_reads(Handle module, Handle to_module, TRAPS);
246
247 // Updates a module to export a package
248 static jvmtiError add_module_exports(Handle module, Handle pkg_name, Handle to_module, TRAPS);
249
250 // Updates a module to open a package
251 static jvmtiError add_module_opens(Handle module, Handle pkg_name, Handle to_module, TRAPS);
252
253 // Add a used service to the module
254 static jvmtiError add_module_uses(Handle module, Handle service, TRAPS);
255
256 // Add a service provider to the module
257 static jvmtiError add_module_provides(Handle module, Handle service, Handle impl_class, TRAPS);
258
259 // let JVMTI know that the JVM_OnLoad code is running
260 static void enter_onload_phase() NOT_JVMTI_RETURN;
261
262 // let JVMTI know that the VM isn't up yet (and JVM_OnLoad code isn't running)
263 static void enter_primordial_phase() NOT_JVMTI_RETURN;
264
265 // let JVMTI know that the VM isn't up yet but JNI is live
266 static void enter_early_start_phase() NOT_JVMTI_RETURN;
267 static void enter_start_phase() NOT_JVMTI_RETURN;
268
269 // let JVMTI know that the VM is fully up and running now
270 static void enter_live_phase() NOT_JVMTI_RETURN;
271
272 // ------ can_* conditions (below) are set at OnLoad and never changed ------------
273 inline static bool can_modify_any_class() {
274 JVMTI_ONLY(return _can_modify_any_class);
275 NOT_JVMTI(return false);
276 }
277 inline static bool can_access_local_variables() {
278 JVMTI_ONLY(return _can_access_local_variables);
279 NOT_JVMTI(return false);
280 }
281 inline static bool can_hotswap_or_post_breakpoint() {
282 JVMTI_ONLY(return _can_hotswap_or_post_breakpoint);
283 NOT_JVMTI(return false);
284 }
285 inline static bool can_walk_any_space() {
286 JVMTI_ONLY(return _can_walk_any_space);
287 NOT_JVMTI(return false);
288 }
289
290 // field access management
291 static address get_field_access_count_addr() NOT_JVMTI_RETURN_(nullptr);
292
293 // field modification management
294 static address get_field_modification_count_addr() NOT_JVMTI_RETURN_(nullptr);
295
296 // -----------------
297
298 static bool is_jvmti_version(jint version) {
299 JVMTI_ONLY(return (version & JVMTI_VERSION_MASK) == JVMTI_VERSION_VALUE);
300 NOT_JVMTI(return false);
301 }
302 static bool is_jvmdi_version(jint version) {
303 JVMTI_ONLY(return (version & JVMTI_VERSION_MASK) == JVMDI_VERSION_VALUE);
304 NOT_JVMTI(return false);
305 }
306 static jint get_jvmti_interface(JavaVM *jvm, void **penv, jint version) NOT_JVMTI_RETURN_(0);
307 static void decode_version_values(jint version, int * major, int * minor,
308 int * micro) NOT_JVMTI_RETURN;
309
310 // If the jvmti_thread_state is absent and any thread filtered event
311 // is enabled globally then it is created.
312 // Otherwise, the thread->jvmti_thread_state() is returned.
313 // The 'allow_suspend' parameter is passed as 'true' by default which work for almost all call sites.
314 // It means that a suspend point need to be organized by this function for virtual threads if the call
315 // to jvmtiEventController::thread_started hits a safepoint and gets a new suspend request.
316 // The 'allow_suspend' parameter must be passed as 'false' if thread is holding a VM lock.
317 static JvmtiThreadState* get_jvmti_thread_state(JavaThread *thread, bool allow_suspend = true);
318
319 // single stepping management methods
320 static void at_single_stepping_point(JavaThread *thread, Method* method, address location) NOT_JVMTI_RETURN;
321 static void expose_single_stepping(JvmtiThreadState* state) NOT_JVMTI_RETURN;
322 static JvmtiThreadState* hide_single_stepping(JavaThread *thread) NOT_JVMTI_RETURN_(nullptr);
323
324 // frame pop management
325 static bool has_frame_pop_for_top_frame(JavaThread *current);
326
327 // Methods that notify the debugger that something interesting has happened in the VM.
328 static void post_early_vm_start () NOT_JVMTI_RETURN;
329 static void post_vm_start () NOT_JVMTI_RETURN;
330 static void post_vm_initialized () NOT_JVMTI_RETURN;
331 static void post_vm_death () NOT_JVMTI_RETURN;
332
333 static void post_single_step (JavaThread *thread, Method* method, address location) NOT_JVMTI_RETURN;
334 static void post_raw_breakpoint (JavaThread *thread, Method* method, address location) NOT_JVMTI_RETURN;
335
336 static void post_exception_throw (JavaThread *thread, Method* method, address location, oop exception) NOT_JVMTI_RETURN;
337 static void notice_unwind_due_to_exception (JavaThread *thread, Method* method, address location, oop exception, bool in_handler_frame) NOT_JVMTI_RETURN;
338
339 static oop jni_GetField_probe (JavaThread *thread, jobject jobj,
340 oop obj, Klass* klass, jfieldID fieldID, bool is_static)
341 NOT_JVMTI_RETURN_(nullptr);
342 static void post_field_access_by_jni (JavaThread *thread, oop obj,
343 Klass* klass, jfieldID fieldID, bool is_static) NOT_JVMTI_RETURN;
344 static void post_field_access (JavaThread *thread, Method* method,
345 address location, Klass* field_klass, Handle object, jfieldID field) NOT_JVMTI_RETURN;
346 static oop jni_SetField_probe (JavaThread *thread, jobject jobj,
347 oop obj, Klass* klass, jfieldID fieldID, bool is_static, char sig_type,
348 jvalue *value) NOT_JVMTI_RETURN_(nullptr);
349 static void post_field_modification_by_jni(JavaThread *thread, oop obj,
350 Klass* klass, jfieldID fieldID, bool is_static, char sig_type,
351 jvalue *value);
352 static void post_raw_field_modification(JavaThread *thread, Method* method,
353 address location, Klass* field_klass, Handle object, jfieldID field,
354 char sig_type, jvalue *value) NOT_JVMTI_RETURN;
355
356 static void post_method_entry (JavaThread *thread, Method* method, frame current_frame) NOT_JVMTI_RETURN;
357 static void post_method_exit (JavaThread *thread, Method* method, frame current_frame) NOT_JVMTI_RETURN;
358
359 static void post_class_load (JavaThread *thread, Klass* klass) NOT_JVMTI_RETURN;
360 static void post_class_unload (Klass* klass) NOT_JVMTI_RETURN;
361 static void post_class_prepare (JavaThread *thread, Klass* klass) NOT_JVMTI_RETURN;
362
363 static void post_thread_start (JavaThread *thread) NOT_JVMTI_RETURN;
364 static void post_thread_end (JavaThread *thread) NOT_JVMTI_RETURN;
365
366 static void post_vthread_start (jthread vthread) NOT_JVMTI_RETURN;
367 static void post_vthread_end (jthread vthread) NOT_JVMTI_RETURN;
368 static void post_vthread_mount (jthread vthread) NOT_JVMTI_RETURN;
369 static void post_vthread_unmount (jthread vthread) NOT_JVMTI_RETURN;
370
371 static void continuation_yield_cleanup (JavaThread* thread, jint continuation_frame_count) NOT_JVMTI_RETURN;
372
373 // Support for java.lang.instrument agent loading.
374 static bool _should_post_class_file_load_hook;
375 inline static void set_should_post_class_file_load_hook(bool on) { _should_post_class_file_load_hook = on; }
376 inline static bool should_post_class_file_load_hook() {
377 JVMTI_ONLY(return _should_post_class_file_load_hook);
378 NOT_JVMTI(return false;)
379 }
380 static bool has_frame_pops(JavaThread* thread) NOT_JVMTI_RETURN_(false);
381 static bool is_early_phase() NOT_JVMTI_RETURN_(false);
382 static bool has_early_class_hook_env() NOT_JVMTI_RETURN_(false);
383 static bool has_early_vmstart_env() NOT_JVMTI_RETURN_(false);
384 static void post_class_file_load_hook(Symbol* h_name, Handle class_loader,
385 Handle h_protection_domain,
386 unsigned char **data_ptr, unsigned char **end_ptr,
387 JvmtiCachedClassFileData **cache_ptr) NOT_JVMTI_RETURN;
388 static void post_native_method_bind(Method* method, address* function_ptr) NOT_JVMTI_RETURN;
389 static void post_compiled_method_load(JvmtiEnv* env, nmethod *nm) NOT_JVMTI_RETURN;
390 static void post_compiled_method_load(nmethod *nm) NOT_JVMTI_RETURN;
391 static void post_dynamic_code_generated(const char *name, const void *code_begin, const void *code_end) NOT_JVMTI_RETURN;
392
393 // used to post a CompiledMethodUnload event
394 static void post_compiled_method_unload(jmethodID mid, const void *code_begin) NOT_JVMTI_RETURN;
395
396 // similar to post_dynamic_code_generated except that it can be used to
397 // post a DynamicCodeGenerated event while holding locks in the VM. Any event
398 // posted using this function is recorded by the enclosing event collector
399 // -- JvmtiDynamicCodeEventCollector.
400 static void post_dynamic_code_generated_while_holding_locks(const char* name, address code_begin, address code_end) NOT_JVMTI_RETURN;
401
402 static void post_garbage_collection_finish() NOT_JVMTI_RETURN;
403 static void post_garbage_collection_start() NOT_JVMTI_RETURN;
404 static void post_data_dump() NOT_JVMTI_RETURN;
405 static void post_monitor_contended_enter(JavaThread *thread, ObjectMonitor *obj_mntr) NOT_JVMTI_RETURN;
406 static void post_monitor_contended_entered(JavaThread *thread, ObjectMonitor *obj_mntr) NOT_JVMTI_RETURN;
407 static void post_monitor_wait(JavaThread *thread, oop obj, jlong timeout) NOT_JVMTI_RETURN;
408 static void post_monitor_waited(JavaThread *thread, ObjectMonitor *obj_mntr, jboolean timed_out) NOT_JVMTI_RETURN;
409 static void vthread_post_monitor_waited(JavaThread *current, ObjectMonitor *obj_mntr, jboolean timed_out) NOT_JVMTI_RETURN;
410 static void post_object_free(JvmtiEnv* env, GrowableArray<jlong>* objects) NOT_JVMTI_RETURN;
411 static void post_resource_exhausted(jint resource_exhausted_flags, const char* detail) NOT_JVMTI_RETURN;
412 static void record_vm_internal_object_allocation(oop object) NOT_JVMTI_RETURN;
413 // Post objects collected by vm_object_alloc_event_collector.
414 static void post_vm_object_alloc(JavaThread *thread, oop object) NOT_JVMTI_RETURN;
415 // Collects vm internal objects for later event posting.
416 inline static void vm_object_alloc_event_collector(oop object) {
417 if (should_post_vm_object_alloc()) {
418 record_vm_internal_object_allocation(object);
419 }
420 }
421
422 // Used by C2 to deoptimize allocation intrinsics and post vm_object_alloc
423 static int _should_notify_object_alloc;
424
425 static void record_sampled_internal_object_allocation(oop object) NOT_JVMTI_RETURN;
426 // Post objects collected by sampled_object_alloc_event_collector.
427 static void post_sampled_object_alloc(JavaThread *thread, oop object) NOT_JVMTI_RETURN;
428
429 // Collects vm internal objects for later event posting.
430 inline static void sampled_object_alloc_event_collector(oop object) {
431 if (should_post_sampled_object_alloc()) {
432 record_sampled_internal_object_allocation(object);
433 }
434 }
435
436 inline static void post_array_size_exhausted() {
437 if (should_post_resource_exhausted()) {
438 post_resource_exhausted(JVMTI_RESOURCE_EXHAUSTED_OOM_ERROR,
439 "Requested array size exceeds VM limit");
440 }
441 }
442
443 static void cleanup_thread (JavaThread* thread) NOT_JVMTI_RETURN;
444 static void clear_detected_exception (JavaThread* thread) NOT_JVMTI_RETURN;
445
446 static void transition_pending_onload_raw_monitors() NOT_JVMTI_RETURN;
447
448 #if INCLUDE_SERVICES
449 // attach support
450 static jint load_agent_library(const char *agent, const char *absParam, const char *options, outputStream* out) NOT_JVMTI_RETURN_(JNI_ERR);
451 #endif
452
453 // SetNativeMethodPrefix support
454 static char** get_all_native_method_prefixes(int* count_ptr) NOT_JVMTI_RETURN_(nullptr);
455
456 // JavaThread lifecycle support:
457 static jvmtiError cv_external_thread_to_JavaThread(ThreadsList * t_list,
458 jthread thread,
459 JavaThread ** jt_pp,
460 oop * thread_oop_p);
461 };
462
463 // Support class used by JvmtiDynamicCodeEventCollector and others. It
464 // describes a single code blob by name and address range.
465 class JvmtiCodeBlobDesc : public CHeapObj<mtInternal> {
466 private:
467 char _name[64];
468 address _code_begin;
469 address _code_end;
470
471 public:
472 JvmtiCodeBlobDesc(const char *name, address code_begin, address code_end) {
473 assert(name != nullptr, "all code blobs must be named");
474 strncpy(_name, name, sizeof(_name) - 1);
475 _name[sizeof(_name)-1] = '\0';
476 _code_begin = code_begin;
477 _code_end = code_end;
478 }
479 char* name() { return _name; }
480 address code_begin() { return _code_begin; }
481 address code_end() { return _code_end; }
482 };
483
484 // JvmtiEventCollector is a helper class to setup thread for
485 // event collection.
486 class JvmtiEventCollector : public StackObj {
487 private:
488 JvmtiEventCollector* _prev; // Save previous one to support nested event collector.
489 bool _unset_jvmti_thread_state;
490
491 public:
492 JvmtiEventCollector() : _prev(nullptr), _unset_jvmti_thread_state(false) {}
493
494 void setup_jvmti_thread_state(); // Set this collector in current thread, returns if success.
495 void unset_jvmti_thread_state(); // Reset previous collector in current thread.
496 virtual bool is_dynamic_code_event() { return false; }
497 virtual bool is_vm_object_alloc_event(){ return false; }
498 virtual bool is_sampled_object_alloc_event(){ return false; }
499 JvmtiEventCollector *get_prev() { return _prev; }
500 };
501
502 // A JvmtiDynamicCodeEventCollector is a helper class for the JvmtiExport
503 // interface. It collects "dynamic code generated" events that are posted
504 // while holding locks. When the event collector goes out of scope the
505 // events will be posted.
506 //
507 // Usage :-
508 //
509 // {
510 // JvmtiDynamicCodeEventCollector event_collector;
511 // :
512 // { MutexLocker ml(...)
513 // :
514 // JvmtiExport::post_dynamic_code_generated_while_holding_locks(...)
515 // }
516 // // event collector goes out of scope => post events to profiler.
517 // }
518
519 class JvmtiDynamicCodeEventCollector : public JvmtiEventCollector {
520 private:
521 GrowableArray<JvmtiCodeBlobDesc*>* _code_blobs; // collected code blob events
522
523 friend class JvmtiExport;
524 void register_stub(const char* name, address start, address end);
525
526 public:
527 JvmtiDynamicCodeEventCollector() NOT_JVMTI_RETURN;
528 ~JvmtiDynamicCodeEventCollector() NOT_JVMTI_RETURN;
529 bool is_dynamic_code_event() { return true; }
530
531 };
532
533 // Used as a base class for object allocation collection and then posting
534 // the allocations to any event notification callbacks.
535 //
536 class JvmtiObjectAllocEventCollector : public JvmtiEventCollector {
537 protected:
538 GrowableArray<OopHandle>* _allocated; // field to record collected allocated object oop.
539 bool _enable; // This flag is enabled in constructor if set up in the thread state
540 // and disabled in destructor before posting event. To avoid
541 // collection of objects allocated while running java code inside
542 // agent post_X_object_alloc() event handler.
543 void (*_post_callback)(JavaThread*, oop); // what callback to use when destroying the collector.
544
545 friend class JvmtiExport;
546
547 // Record allocated object oop.
548 inline void record_allocation(oop obj);
549
550 public:
551 JvmtiObjectAllocEventCollector() NOT_JVMTI_RETURN;
552
553 void generate_call_for_allocated();
554
555 bool is_enabled() { return _enable; }
556 void set_enabled(bool on) { _enable = on; }
557 };
558
559 // Used to record vm internally allocated object oops and post
560 // vm object alloc event for objects visible to java world.
561 // Constructor enables JvmtiThreadState flag and all vm allocated
562 // objects are recorded in a growable array. When destructor is
563 // called the vm object alloc event is posted for each object
564 // visible to java world.
565 // See jvm.cpp file for its usage.
566 //
567 class JvmtiVMObjectAllocEventCollector : public JvmtiObjectAllocEventCollector {
568 public:
569 JvmtiVMObjectAllocEventCollector() NOT_JVMTI_RETURN;
570 ~JvmtiVMObjectAllocEventCollector() NOT_JVMTI_RETURN;
571 virtual bool is_vm_object_alloc_event() { return true; }
572 };
573
574 // Used to record sampled allocated object oops and post
575 // sampled object alloc event.
576 // Constructor enables JvmtiThreadState flag and all sampled allocated
577 // objects are recorded in a growable array. When destructor is
578 // called the sampled object alloc event is posted for each sampled object.
579 // See jvm.cpp file for its usage.
580 //
581 class JvmtiSampledObjectAllocEventCollector : public JvmtiObjectAllocEventCollector {
582 public:
583 JvmtiSampledObjectAllocEventCollector(bool should_start = true) {
584 JVMTI_ONLY(if (should_start) start();)
585 }
586 ~JvmtiSampledObjectAllocEventCollector() NOT_JVMTI_RETURN;
587 bool is_sampled_object_alloc_event() { return true; }
588 void start() NOT_JVMTI_RETURN;
589 static bool object_alloc_is_safe_to_sample() NOT_JVMTI_RETURN_(false);
590 };
591
592 // Marker class to temporary disable posting of jvmti events.
593 class NoJvmtiEventsMark : public StackObj {
594
595 public:
596 NoJvmtiEventsMark() NOT_JVMTI_RETURN;
597 ~NoJvmtiEventsMark() NOT_JVMTI_RETURN;
598 };
599
600
601 // Base class for reporting GC events to JVMTI.
602 class JvmtiGCMarker : public StackObj {
603 public:
604 JvmtiGCMarker() NOT_JVMTI_RETURN;
605 ~JvmtiGCMarker() NOT_JVMTI_RETURN;
606 };
607
608 // JvmtiHideSingleStepping is a helper class for hiding
609 // internal single step events.
610 class JvmtiHideSingleStepping : public StackObj {
611 private:
612 JvmtiThreadState* _state;
613
614 public:
615 JvmtiHideSingleStepping(JavaThread * thread) : _state(nullptr) {
616 assert(thread != nullptr, "sanity check");
617
618 if (JvmtiExport::should_post_single_step()) {
619 _state = JvmtiExport::hide_single_stepping(thread);
620 }
621 }
622
623 ~JvmtiHideSingleStepping() {
624 if (_state != nullptr) {
625 JvmtiExport::expose_single_stepping(_state);
626 }
627 }
628 };
629
630 #endif // SHARE_PRIMS_JVMTIEXPORT_HPP