1 /*
2 * Copyright (c) 2003, 2024, 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_JVMTIENVBASE_HPP
26 #define SHARE_PRIMS_JVMTIENVBASE_HPP
27
28 #include "prims/jvmtiEnvThreadState.hpp"
29 #include "prims/jvmtiEventController.hpp"
30 #include "prims/jvmtiThreadState.hpp"
31 #include "oops/oopHandle.hpp"
32 #include "runtime/atomic.hpp"
33 #include "runtime/fieldDescriptor.hpp"
34 #include "runtime/frame.hpp"
35 #include "runtime/javaThread.hpp"
36 #include "runtime/threads.hpp"
37 #include "runtime/vmOperation.hpp"
38 #include "utilities/growableArray.hpp"
39 #include "utilities/macros.hpp"
40
41 //
42 // Forward Declarations
43 //
44
45 class JvmtiEnv;
46 class JvmtiThreadState;
47 class JvmtiRawMonitor; // for jvmtiEnv.hpp
48 class JvmtiEventControllerPrivate;
49 class JvmtiTagMap;
50
51
52
53 // One JvmtiEnv object is created per jvmti attachment;
54 // done via JNI GetEnv() call. Multiple attachments are
55 // allowed in jvmti.
56
57 class JvmtiEnvBase : public CHeapObj<mtInternal> {
58
59 private:
60
61 #if INCLUDE_JVMTI
62 static JvmtiEnvBase* _head_environment; // head of environment list
63 #endif // INCLUDE_JVMTI
64
65 static bool _globally_initialized;
66 static jvmtiPhase _phase;
67 static volatile int _dying_thread_env_iteration_count;
68
69 public:
70
71 enum {
72 JDK15_JVMTI_VERSION = JVMTI_VERSION_1_0 + 33, /* version: 1.0.33 */
73 JDK16_JVMTI_VERSION = JVMTI_VERSION_1_1 + 102, /* version: 1.1.102 */
74 JDK17_JVMTI_VERSION = JVMTI_VERSION_1_2 + 2 /* version: 1.2.2 */
75 };
76
77 static jvmtiPhase get_phase() { return _phase; }
78 static jvmtiPhase get_phase(jvmtiEnv* env) { return ((JvmtiEnvBase*)JvmtiEnv_from_jvmti_env(env))->phase(); }
79 static void set_phase(jvmtiPhase phase) { _phase = phase; }
80 static bool is_vm_live() { return _phase == JVMTI_PHASE_LIVE; }
81
82 static void entering_dying_thread_env_iteration() { ++_dying_thread_env_iteration_count; }
83 static void leaving_dying_thread_env_iteration() { --_dying_thread_env_iteration_count; }
84 static bool is_inside_dying_thread_env_iteration(){ return _dying_thread_env_iteration_count > 0; }
85
86 // This function is to support agents loaded into running VM.
87 static bool enable_virtual_threads_notify_jvmti();
88
89 // This function is used in WhiteBox, only needed to test the function above.
90 // It is unsafe to use this function when virtual threads are executed.
91 static bool disable_virtual_threads_notify_jvmti();
92
93 static jvmtiError suspend_thread(oop thread_oop, JavaThread* java_thread, bool single_suspend,
94 int* need_safepoint_p);
95 static jvmtiError resume_thread(oop thread_oop, JavaThread* java_thread, bool single_resume);
96 static jvmtiError check_thread_list(jint count, const jthread* list);
97 static bool is_in_thread_list(jint count, const jthread* list, oop jt_oop);
98
99 // check if thread_oop represents a thread carrying a virtual thread
100 static bool is_thread_carrying_vthread(JavaThread* java_thread, oop thread_oop) {
101 return java_thread != nullptr && java_thread->jvmti_vthread() != nullptr
102 && java_thread->jvmti_vthread() != thread_oop
103 && java_thread->threadObj() == thread_oop;
104 }
105
106 private:
107
108 enum {
109 JVMTI_MAGIC = 0x71EE,
110 DISPOSED_MAGIC = 0xDEFC,
111 BAD_MAGIC = 0xDEAD
112 };
113
114 jvmtiEnv _jvmti_external;
115 jint _magic;
116 jint _version; // version value passed to JNI GetEnv()
117 JvmtiEnvBase* _next;
118 bool _is_retransformable;
119 const void *_env_local_storage; // per env agent allocated data.
120 jvmtiEventCallbacks _event_callbacks;
121 jvmtiExtEventCallbacks _ext_event_callbacks;
122 JvmtiTagMap* volatile _tag_map;
123 JvmtiEnvEventEnable _env_event_enable;
124 jvmtiCapabilities _current_capabilities;
125 jvmtiCapabilities _prohibited_capabilities;
126 volatile bool _class_file_load_hook_ever_enabled;
127 static volatile bool _needs_clean_up;
128 char** _native_method_prefixes;
129 int _native_method_prefix_count;
130
131 protected:
132 JvmtiEnvBase(jint version);
133 ~JvmtiEnvBase();
134 void dispose();
135 void env_dispose();
136
137 void set_env_local_storage(const void* data) { _env_local_storage = data; }
138
139 void record_class_file_load_hook_enabled();
140 void record_first_time_class_file_load_hook_enabled();
141
142 char** get_native_method_prefixes() { return _native_method_prefixes; }
143 int get_native_method_prefix_count() { return _native_method_prefix_count; }
144 jvmtiError set_native_method_prefixes(jint prefix_count, char** prefixes);
145
146 private:
147 friend class JvmtiEventControllerPrivate;
148 void initialize();
149 void set_event_callbacks(const jvmtiEventCallbacks* callbacks, jint size_of_callbacks);
150 static void globally_initialize();
151 static void periodic_clean_up();
152
153 friend class JvmtiEnvIterator;
154 JvmtiEnv* next_environment() { return (JvmtiEnv*)_next; }
155 void set_next_environment(JvmtiEnvBase* env) { _next = env; }
156 static JvmtiEnv* head_environment() {
157 JVMTI_ONLY(return (JvmtiEnv*)_head_environment);
158 NOT_JVMTI(return nullptr);
159 }
160
161 public:
162
163 jvmtiPhase phase();
164 bool is_valid();
165
166 bool use_version_1_0_semantics(); // agent asked for version 1.0
167 bool use_version_1_1_semantics(); // agent asked for version 1.1
168 bool use_version_1_2_semantics(); // agent asked for version 1.2
169
170 bool is_retransformable() { return _is_retransformable; }
171
172 const void* get_env_local_storage() { return _env_local_storage; }
173
174 static ByteSize jvmti_external_offset() {
175 return byte_offset_of(JvmtiEnvBase, _jvmti_external);
176 };
177
178 // If (thread == nullptr) then return current thread object.
179 // Otherwise return JNIHandles::resolve_external_guard(thread).
180 static oop current_thread_obj_or_resolve_external_guard(jthread thread);
181
182 // Return true if the thread identified with a pair <jt,thr_obj> is current.
183 // A thread carrying a virtual thread is not treated as current.
184 static bool is_JavaThread_current(JavaThread* jt, oop thr_obj) {
185 JavaThread* current = JavaThread::current();
186 // jt can be null in case of a virtual thread
187 if (jt == nullptr || jt != current) {
188 return false;
189 }
190 oop cur_obj = current->jvmti_vthread();
191
192 // cur_obj == nullptr is true for normal platform threads only
193 // otherwise it can be virtual or carrier thread.
194 return cur_obj == nullptr || cur_obj == thr_obj;
195 }
196
197 static jvmtiError get_JavaThread(ThreadsList* tlist, jthread thread, JavaThread** jt_pp) {
198 jvmtiError err = JVMTI_ERROR_NONE;
199 if (thread == nullptr) {
200 *jt_pp = JavaThread::current();
201 } else {
202 err = JvmtiExport::cv_external_thread_to_JavaThread(tlist, thread, jt_pp, nullptr);
203 }
204 return err;
205 }
206
207 // If there is a virtual thread mounted on the JavaThread* then
208 // return virtual thread oop. Otherwise, return thread oop.
209 static oop get_vthread_or_thread_oop(JavaThread* jt) {
210 oop result = jt->threadObj();
211 if (jt->jvmti_vthread() != nullptr) {
212 result = jt->jvmti_vthread();
213 }
214 return result;
215 }
216
217 static jvmtiError get_threadOop_and_JavaThread(ThreadsList* t_list, jthread thread, JavaThread* cur_thread,
218 JavaThread** jt_pp, oop* thread_oop_p);
219
220 // Return true if java thread is a carrier thread with a mounted virtual thread.
221 static bool is_cthread_with_mounted_vthread(JavaThread* jt);
222 static bool is_cthread_with_continuation(JavaThread* jt);
223
224 // Check if VirtualThread or BoundVirtualThread is suspended.
225 static bool is_vthread_suspended(oop vt_oop, JavaThread* jt);
226
227 // Check for JVMTI_ERROR_NOT_SUSPENDED and JVMTI_ERROR_OPAQUE_FRAME errors.
228 // Used in PopFrame and ForceEarlyReturn implementations.
229 static jvmtiError check_non_suspended_or_opaque_frame(JavaThread* jt, oop thr_obj, bool self);
230
231 static JvmtiEnv* JvmtiEnv_from_jvmti_env(jvmtiEnv *env) {
232 return (JvmtiEnv*)((intptr_t)env - in_bytes(jvmti_external_offset()));
233 };
234
235 jvmtiCapabilities *get_capabilities() { return &_current_capabilities; }
236
237 jvmtiCapabilities *get_prohibited_capabilities() { return &_prohibited_capabilities; }
238
239 bool early_class_hook_env() {
240 return get_capabilities()->can_generate_early_class_hook_events != 0
241 && get_capabilities()->can_generate_all_class_hook_events != 0;
242 }
243
244 bool early_vmstart_env() {
245 return get_capabilities()->can_generate_early_vmstart != 0;
246 }
247
248 static char** get_all_native_method_prefixes(int* count_ptr);
249
250 // This test will answer true when all environments have been disposed and some have
251 // not yet been deallocated. As a result, this test should only be used as an
252 // optimization for the no environment case.
253 static bool environments_might_exist() {
254 return head_environment() != nullptr;
255 }
256
257 static void check_for_periodic_clean_up();
258
259 JvmtiEnvEventEnable *env_event_enable() {
260 return &_env_event_enable;
261 }
262
263 jvmtiError allocate(jlong size, unsigned char** mem_ptr) {
264 if (size < 0) {
265 return JVMTI_ERROR_ILLEGAL_ARGUMENT;
266 }
267 if (size == 0) {
268 *mem_ptr = nullptr;
269 } else {
270 *mem_ptr = (unsigned char *)os::malloc((size_t)size, mtInternal);
271 if (*mem_ptr == nullptr) {
272 return JVMTI_ERROR_OUT_OF_MEMORY;
273 }
274 }
275 return JVMTI_ERROR_NONE;
276 }
277
278 jvmtiError deallocate(unsigned char* mem) {
279 if (mem != nullptr) {
280 os::free(mem);
281 }
282 return JVMTI_ERROR_NONE;
283 }
284
285
286 // Memory functions
287 unsigned char* jvmtiMalloc(jlong size); // don't use this - call allocate
288
289 // method to create a local handle
290 jobject jni_reference(Handle hndl);
291
292 // method to create a local handle.
293 // This function allows caller to specify which
294 // threads local handle table to use.
295 jobject jni_reference(JavaThread *thread, Handle hndl);
296
297 // method to destroy a local handle
298 void destroy_jni_reference(jobject jobj);
299
300 // method to destroy a local handle.
301 // This function allows caller to specify which
302 // threads local handle table to use.
303 void destroy_jni_reference(JavaThread *thread, jobject jobj);
304
305 jvmtiEnv* jvmti_external() { return &_jvmti_external; };
306
307 // Event Dispatch
308
309 bool has_callback(jvmtiEvent event_type) {
310 assert(event_type >= JVMTI_MIN_EVENT_TYPE_VAL &&
311 event_type <= JVMTI_MAX_EVENT_TYPE_VAL, "checking");
312 return ((void**)&_event_callbacks)[event_type-JVMTI_MIN_EVENT_TYPE_VAL] != nullptr;
313 }
314
315 jvmtiEventCallbacks* callbacks() {
316 return &_event_callbacks;
317 }
318
319 jvmtiExtEventCallbacks* ext_callbacks() {
320 return &_ext_event_callbacks;
321 }
322
323 void set_tag_map(JvmtiTagMap* tag_map) {
324 _tag_map = tag_map;
325 }
326
327 JvmtiTagMap* tag_map() {
328 return _tag_map;
329 }
330
331 JvmtiTagMap* tag_map_acquire() {
332 return Atomic::load_acquire(&_tag_map);
333 }
334
335 void release_set_tag_map(JvmtiTagMap* tag_map) {
336 Atomic::release_store(&_tag_map, tag_map);
337 }
338
339 // return true if event is enabled globally or for any thread
340 // True only if there is a callback for it.
341 bool is_enabled(jvmtiEvent event_type) {
342 return _env_event_enable.is_enabled(event_type);
343 }
344
345 // Random Utilities
346
347 protected:
348 // helper methods for creating arrays of global JNI Handles from local Handles
349 // allocated into environment specific storage
350 jthread * new_jthreadArray(int length, Handle *handles);
351 jthreadGroup * new_jthreadGroupArray(int length, objArrayHandle groups);
352
353 // convert to a jni jclass from a non-null Klass*
354 jclass get_jni_class_non_null(Klass* k);
355
356 jint count_locked_objects(JavaThread *java_thread, Handle hobj);
357 jvmtiError get_locked_objects_in_frame(JavaThread *calling_thread,
358 JavaThread* java_thread,
359 javaVFrame *jvf,
360 GrowableArray<jvmtiMonitorStackDepthInfo*>* owned_monitors_list,
361 jint depth);
362 public:
363 static javaVFrame* jvf_for_thread_and_depth(JavaThread* java_thread, jint depth);
364
365 // get a field descriptor for the specified class and field
366 static bool get_field_descriptor(Klass* k, jfieldID field, fieldDescriptor* fd);
367
368 // check and skip frames hidden in mount/unmount transitions
369 static javaVFrame* check_and_skip_hidden_frames(bool is_in_VTMS_transition, javaVFrame* jvf);
370 static javaVFrame* check_and_skip_hidden_frames(JavaThread* jt, javaVFrame* jvf);
371 static javaVFrame* check_and_skip_hidden_frames(oop vthread, javaVFrame* jvf);
372
373 // check if virtual thread is not terminated (alive)
374 static bool is_vthread_alive(oop vt);
375
376 // return JavaThread if virtual thread is mounted, null otherwise
377 static JavaThread* get_JavaThread_or_null(oop vthread);
378
379 // get virtual thread last java vframe
380 static javaVFrame* get_vthread_jvf(oop vthread);
381
382 // get carrier thread last java vframe
383 static javaVFrame* get_cthread_last_java_vframe(JavaThread* jt, RegisterMap* reg_map);
384
385 // get platform thread state
386 static jint get_thread_state_base(oop thread_oop, JavaThread* jt);
387 static jint get_thread_state(oop thread_oop, JavaThread* jt);
388
389 // get virtual thread state
390 static jint get_vthread_state(oop thread_oop, JavaThread* jt);
391
392 // get platform or virtual thread state
393 static jint get_thread_or_vthread_state(oop thread_oop, JavaThread* jt);
394
395 // enumerates the live threads in the given thread group
396 static jvmtiError get_live_threads(JavaThread* current_thread, Handle group_hdl, jint *count_ptr, Handle **thread_objs_p);
397
398 // enumerates the subgroups in the given thread group
399 static jvmtiError get_subgroups(JavaThread* current_thread, Handle group_hdl, jint *count_ptr, objArrayHandle *group_objs_p);
400
401 // JVMTI API helper functions which are called when target thread is suspended
402 // or at safepoint / thread local handshake.
403 static jint get_frame_count(javaVFrame* jvf);
404 jvmtiError get_frame_count(JavaThread* java_thread, jint *count_ptr);
405 jvmtiError get_frame_count(oop frame_oop, jint *count_ptr);
406 jvmtiError get_frame_location(javaVFrame* jvf, jint depth,
407 jmethodID* method_ptr, jlocation* location_ptr);
408 jvmtiError get_frame_location(JavaThread* java_thread, jint depth,
409 jmethodID* method_ptr, jlocation* location_ptr);
410 jvmtiError get_frame_location(oop vthread_oop, jint depth,
411 jmethodID* method_ptr, jlocation* location_ptr);
412 jvmtiError set_frame_pop(JvmtiThreadState* state, javaVFrame* jvf, jint depth);
413 jvmtiError get_object_monitor_usage(JavaThread* calling_thread,
414 jobject object, jvmtiMonitorUsage* info_ptr);
415 jvmtiError get_stack_trace(javaVFrame* jvf,
416 jint stack_depth, jint max_count,
417 jvmtiFrameInfo* frame_buffer, jint* count_ptr);
418 jvmtiError get_stack_trace(JavaThread* java_thread,
419 jint stack_depth, jint max_count,
420 jvmtiFrameInfo* frame_buffer, jint* count_ptr);
421 jvmtiError get_current_contended_monitor(JavaThread* calling_thread, JavaThread* java_thread,
422 jobject* monitor_ptr, bool is_virtual);
423 jvmtiError get_owned_monitors(JavaThread* calling_thread, JavaThread* java_thread,
424 GrowableArray<jvmtiMonitorStackDepthInfo*> *owned_monitors_list);
425 jvmtiError get_owned_monitors(JavaThread* calling_thread, JavaThread* java_thread, javaVFrame* jvf,
426 GrowableArray<jvmtiMonitorStackDepthInfo*> *owned_monitors_list);
427 static jvmtiError check_top_frame(Thread* current_thread, JavaThread* java_thread,
428 jvalue value, TosState tos, Handle* ret_ob_h);
429 jvmtiError force_early_return(jthread thread, jvalue value, TosState tos);
430 };
431
432 // This class is the only safe means of iterating through environments.
433 // Note that this iteratation includes invalid environments pending
434 // deallocation -- in fact, some uses depend on this behavior.
435
436 class JvmtiEnvIterator : public StackObj {
437 private:
438 bool _entry_was_marked;
439 public:
440 JvmtiEnvIterator() {
441 if (Threads::number_of_threads() == 0) {
442 _entry_was_marked = false; // we are single-threaded, no need
443 } else {
444 Thread::current()->entering_jvmti_env_iteration();
445 _entry_was_marked = true;
446 }
447 }
448 ~JvmtiEnvIterator() {
449 if (_entry_was_marked) {
450 Thread::current()->leaving_jvmti_env_iteration();
451 }
452 }
453 JvmtiEnv* first() { return JvmtiEnvBase::head_environment(); }
454 JvmtiEnv* next(JvmtiEnvBase* env) { return env->next_environment(); }
455 };
456
457 // Used in combination with the JvmtiHandshake class.
458 // It is intended to support both platform and virtual threads.
459 class JvmtiUnitedHandshakeClosure : public HandshakeClosure {
460 protected:
461 jvmtiError _result;
462 // the fields below are set by the JvmtiHandshake::execute
463 JavaThread* _target_jt;
464 bool _is_virtual;
465 bool _self;
466 public:
467 JvmtiUnitedHandshakeClosure(const char* name)
468 : HandshakeClosure(name),
469 _result(JVMTI_ERROR_THREAD_NOT_ALIVE),
470 _target_jt(nullptr),
471 _is_virtual(false),
472 _self(false) {}
473
474 void set_result(jvmtiError err) { _result = err; }
475 void set_target_jt(JavaThread* target_jt) { _target_jt = target_jt; }
476 void set_is_virtual(bool val) { _is_virtual = val; }
477 void set_self(bool val) { _self = val; }
478 jvmtiError result() { return _result; }
479 virtual void do_vthread(Handle target_h) = 0;
480 };
481
482 // The JvmtiHandshake supports virtual threads.
483 class JvmtiHandshake : public Handshake {
484 public:
485 static void execute(JvmtiUnitedHandshakeClosure* hs_cl, ThreadsListHandle* tlh,
486 JavaThread* target_jt, Handle target_h);
487 static void execute(JvmtiUnitedHandshakeClosure* hs_cl, jthread target);
488 };
489
490 class SetForceEarlyReturn : public JvmtiUnitedHandshakeClosure {
491 private:
492 JvmtiThreadState* _state;
493 jvalue _value;
494 TosState _tos;
495 public:
496 SetForceEarlyReturn(JvmtiThreadState* state, jvalue value, TosState tos)
497 : JvmtiUnitedHandshakeClosure("SetForceEarlyReturn"),
498 _state(state),
499 _value(value),
500 _tos(tos) {}
501 void doit(Thread *target);
502 void do_thread(Thread *target) {
503 doit(target);
504 }
505 void do_vthread(Handle target_h) {
506 assert(_target_jt != nullptr, "sanity check");
507 // Use jvmti_vthread() instead of vthread() as target could have temporarily changed
508 // identity to carrier thread (see VirtualThread.switchToCarrierThread).
509 assert(_target_jt->jvmti_vthread() == target_h(), "sanity check");
510 doit(_target_jt); // mounted virtual thread
511 }
512 };
513
514 // HandshakeClosure to update for pop top frame.
515 class UpdateForPopTopFrameClosure : public JvmtiUnitedHandshakeClosure {
516 private:
517 JvmtiThreadState* _state;
518
519 public:
520 UpdateForPopTopFrameClosure(JvmtiThreadState* state)
521 : JvmtiUnitedHandshakeClosure("UpdateForPopTopFrame"),
522 _state(state) {}
523 void doit(Thread *target);
524 void do_thread(Thread *target) {
525 doit(target);
526 }
527 void do_vthread(Handle target_h) {
528 assert(_target_jt != nullptr, "sanity check");
529 // Use jvmti_vthread() instead of vthread() as target could have temporarily changed
530 // identity to carrier thread (see VirtualThread.switchToCarrierThread).
531 assert(_target_jt->jvmti_vthread() == target_h(), "sanity check");
532 doit(_target_jt); // mounted virtual thread
533 }
534 };
535
536 // HandshakeClosure to set frame pop.
537 class SetFramePopClosure : public JvmtiUnitedHandshakeClosure {
538 private:
539 JvmtiEnv *_env;
540 JvmtiThreadState* _state;
541 jint _depth;
542
543 public:
544 SetFramePopClosure(JvmtiEnv *env, JvmtiThreadState* state, jint depth)
545 : JvmtiUnitedHandshakeClosure("SetFramePopClosure"),
546 _env(env),
547 _state(state),
548 _depth(depth) {}
549 void do_thread(Thread *target);
550 void do_vthread(Handle target_h);
551 };
552
553 // HandshakeClosure to get monitor information with stack depth.
554 class GetOwnedMonitorInfoClosure : public JvmtiUnitedHandshakeClosure {
555 private:
556 JvmtiEnv *_env;
557 JavaThread* _calling_thread;
558 GrowableArray<jvmtiMonitorStackDepthInfo*> *_owned_monitors_list;
559
560 public:
561 GetOwnedMonitorInfoClosure(JvmtiEnv* env,
562 JavaThread* calling_thread,
563 GrowableArray<jvmtiMonitorStackDepthInfo*>* owned_monitors_list)
564 : JvmtiUnitedHandshakeClosure("GetOwnedMonitorInfo"),
565 _env(env),
566 _calling_thread(calling_thread),
567 _owned_monitors_list(owned_monitors_list) {}
568
569 void do_thread(Thread *target);
570 void do_vthread(Handle target_h);
571 };
572
573 // VM operation to get object monitor usage.
574 class VM_GetObjectMonitorUsage : public VM_Operation {
575 private:
576 JvmtiEnv *_env;
577 jobject _object;
578 JavaThread* _calling_thread;
579 jvmtiMonitorUsage* _info_ptr;
580 jvmtiError _result;
581
582 public:
583 VM_GetObjectMonitorUsage(JvmtiEnv *env, JavaThread* calling_thread, jobject object, jvmtiMonitorUsage* info_ptr) {
584 _env = env;
585 _object = object;
586 _calling_thread = calling_thread;
587 _info_ptr = info_ptr;
588 }
589 VMOp_Type type() const { return VMOp_GetObjectMonitorUsage; }
590 jvmtiError result() { return _result; }
591 void doit() {
592 _result = ((JvmtiEnvBase*) _env)->get_object_monitor_usage(_calling_thread, _object, _info_ptr);
593 }
594
595 };
596
597 // HandshakeClosure to get current contended monitor. It is used for both platform and virtual threads.
598 class GetCurrentContendedMonitorClosure : public JvmtiUnitedHandshakeClosure {
599 private:
600 JvmtiEnv *_env;
601 JavaThread *_calling_thread;
602 jobject *_owned_monitor_ptr;
603
604 public:
605 GetCurrentContendedMonitorClosure(JvmtiEnv *env,
606 JavaThread* calling_thread,
607 jobject *owned_monitor_ptr)
608 : JvmtiUnitedHandshakeClosure("GetCurrentContendedMonitor"),
609 _env(env),
610 _calling_thread(calling_thread),
611 _owned_monitor_ptr(owned_monitor_ptr) {}
612 void do_thread(Thread *target);
613 void do_vthread(Handle target_h);
614 };
615
616 // HandshakeClosure to get stack trace.
617 class GetStackTraceClosure : public JvmtiUnitedHandshakeClosure {
618 private:
619 JvmtiEnv *_env;
620 jint _start_depth;
621 jint _max_count;
622 jvmtiFrameInfo *_frame_buffer;
623 jint *_count_ptr;
624
625 public:
626 GetStackTraceClosure(JvmtiEnv *env, jint start_depth, jint max_count,
627 jvmtiFrameInfo* frame_buffer, jint* count_ptr)
628 : JvmtiUnitedHandshakeClosure("GetStackTrace"),
629 _env(env),
630 _start_depth(start_depth),
631 _max_count(max_count),
632 _frame_buffer(frame_buffer),
633 _count_ptr(count_ptr) {}
634 void do_thread(Thread *target);
635 void do_vthread(Handle target_h);
636 };
637
638 #ifdef ASSERT
639 // HandshakeClosure to print stack trace in JvmtiVTMSTransitionDisabler error handling.
640 class PrintStackTraceClosure : public HandshakeClosure {
641 public:
642 static void do_thread_impl(Thread *target);
643
644 PrintStackTraceClosure()
645 : HandshakeClosure("PrintStackTraceClosure") {}
646 void do_thread(Thread *target);
647 };
648 #endif
649
650 // Forward declaration.
651 struct StackInfoNode;
652
653 // Get stack trace at safepoint or at direct handshake.
654 class MultipleStackTracesCollector {
655 private:
656 friend class VM_GetThreadListStackTraces;
657 JvmtiEnv *_env;
658 jint _max_frame_count;
659 jvmtiStackInfo *_stack_info;
660 jvmtiError _result;
661 int _frame_count_total;
662 struct StackInfoNode *_head;
663
664 JvmtiEnvBase *env() { return (JvmtiEnvBase *)_env; }
665 jint max_frame_count() { return _max_frame_count; }
666 struct StackInfoNode *head() { return _head; }
667 void set_head(StackInfoNode *head) { _head = head; }
668
669 public:
670 MultipleStackTracesCollector(JvmtiEnv *env, jint max_frame_count)
671 : _env(env),
672 _max_frame_count(max_frame_count),
673 _stack_info(nullptr),
674 _result(JVMTI_ERROR_NONE),
675 _frame_count_total(0),
676 _head(nullptr) {
677 }
678 void set_result(jvmtiError result) { _result = result; }
679 void fill_frames(jthread jt, JavaThread *thr, oop thread_oop);
680 void allocate_and_fill_stacks(jint thread_count);
681 jvmtiStackInfo *stack_info() { return _stack_info; }
682 jvmtiError result() { return _result; }
683 };
684
685
686 // VM operation to get stack trace at safepoint.
687 class VM_GetAllStackTraces : public VM_Operation {
688 private:
689 JavaThread *_calling_thread;
690 jint _final_thread_count;
691 MultipleStackTracesCollector _collector;
692
693 public:
694 VM_GetAllStackTraces(JvmtiEnv *env, JavaThread *calling_thread,
695 jint max_frame_count)
696 : _calling_thread(calling_thread),
697 _final_thread_count(0),
698 _collector(env, max_frame_count) {
699 }
700 VMOp_Type type() const { return VMOp_GetAllStackTraces; }
701 void doit();
702 jint final_thread_count() { return _final_thread_count; }
703 jvmtiStackInfo *stack_info() { return _collector.stack_info(); }
704 jvmtiError result() { return _collector.result(); }
705 };
706
707 // VM operation to get stack trace at safepoint.
708 class VM_GetThreadListStackTraces : public VM_Operation {
709 private:
710 jint _thread_count;
711 const jthread* _thread_list;
712 MultipleStackTracesCollector _collector;
713
714 JvmtiEnvBase *env() { return _collector.env(); }
715
716 public:
717 VM_GetThreadListStackTraces(JvmtiEnv *env, jint thread_count, const jthread* thread_list, jint max_frame_count)
718 : _thread_count(thread_count),
719 _thread_list(thread_list),
720 _collector(env, max_frame_count) {
721 }
722 VMOp_Type type() const { return VMOp_GetThreadListStackTraces; }
723 void doit();
724 jvmtiStackInfo *stack_info() { return _collector.stack_info(); }
725 jvmtiError result() { return _collector.result(); }
726 };
727
728 // HandshakeClosure to get single stack trace.
729 class GetSingleStackTraceClosure : public JvmtiUnitedHandshakeClosure {
730 private:
731 JavaThread *_calling_thread;
732 jthread _jthread;
733 MultipleStackTracesCollector _collector;
734
735 public:
736 GetSingleStackTraceClosure(JvmtiEnv *env, JavaThread *calling_thread,
737 jthread thread, jint max_frame_count)
738 : JvmtiUnitedHandshakeClosure("GetSingleStackTrace"),
739 _calling_thread(calling_thread),
740 _jthread(thread),
741 _collector(env, max_frame_count) {
742 }
743 void do_thread(Thread *target);
744 void do_vthread(Handle target_h);
745 void doit();
746 jvmtiStackInfo *stack_info() { return _collector.stack_info(); }
747 jvmtiError result() { return _result; }
748 };
749
750 // HandshakeClosure to count stack frames.
751 class GetFrameCountClosure : public JvmtiUnitedHandshakeClosure {
752 private:
753 JvmtiEnv *_env;
754 jint *_count_ptr;
755
756 public:
757 GetFrameCountClosure(JvmtiEnv *env, jint *count_ptr)
758 : JvmtiUnitedHandshakeClosure("GetFrameCount"),
759 _env(env),
760 _count_ptr(count_ptr) {}
761 void do_thread(Thread *target);
762 void do_vthread(Handle target_h);
763 };
764
765 // HandshakeClosure to get frame location.
766 class GetFrameLocationClosure : public JvmtiUnitedHandshakeClosure {
767 private:
768 JvmtiEnv *_env;
769 jint _depth;
770 jmethodID* _method_ptr;
771 jlocation* _location_ptr;
772
773 public:
774 GetFrameLocationClosure(JvmtiEnv *env, jint depth,
775 jmethodID* method_ptr, jlocation* location_ptr)
776 : JvmtiUnitedHandshakeClosure("GetFrameLocation"),
777 _env(env),
778 _depth(depth),
779 _method_ptr(method_ptr),
780 _location_ptr(location_ptr) {}
781 void do_thread(Thread *target);
782 void do_vthread(Handle target_h);
783 };
784
785 // ResourceTracker
786 //
787 // ResourceTracker works a little like a ResourceMark. All allocates
788 // using the resource tracker are recorded. If an allocate using the
789 // resource tracker fails the destructor will free any resources
790 // that were allocated using the tracker.
791 // The motive for this class is to avoid messy error recovery code
792 // in situations where multiple allocations are done in sequence. If
793 // the second or subsequent allocation fails it avoids any code to
794 // release memory allocated in the previous calls.
795 //
796 // Usage :-
797 // ResourceTracker rt(env);
798 // :
799 // err = rt.allocate(1024, &ptr);
800
801 class ResourceTracker : public StackObj {
802 private:
803 JvmtiEnv* _env;
804 GrowableArray<unsigned char*> *_allocations;
805 bool _failed;
806 public:
807 ResourceTracker(JvmtiEnv* env);
808 ~ResourceTracker();
809 jvmtiError allocate(jlong size, unsigned char** mem_ptr);
810 unsigned char* allocate(jlong size);
811 char* strdup(const char* str);
812 };
813
814
815 // Jvmti monitor closure to collect off stack monitors.
816 class JvmtiMonitorClosure: public MonitorClosure {
817 private:
818 JavaThread *_calling_thread;
819 GrowableArray<jvmtiMonitorStackDepthInfo*> *_owned_monitors_list;
820 jvmtiError _error;
821 JvmtiEnvBase *_env;
822
823 public:
824 JvmtiMonitorClosure(JavaThread *calling_thread,
825 GrowableArray<jvmtiMonitorStackDepthInfo*> *owned_monitors,
826 JvmtiEnvBase *env) {
827 _calling_thread = calling_thread;
828 _owned_monitors_list = owned_monitors;
829 _error = JVMTI_ERROR_NONE;
830 _env = env;
831 }
832 void do_monitor(ObjectMonitor* mon);
833 jvmtiError error() { return _error;}
834 };
835
836
837 // Jvmti module closure to collect all modules loaded to the system.
838 class JvmtiModuleClosure : public StackObj {
839 private:
840 static GrowableArray<OopHandle> *_tbl; // Protected with Module_lock
841
842 static void do_module(ModuleEntry* entry);
843 public:
844 jvmtiError get_all_modules(JvmtiEnv* env, jint* module_count_ptr, jobject** modules_ptr);
845 };
846
847 #endif // SHARE_PRIMS_JVMTIENVBASE_HPP