1 /*
2 * Copyright (c) 1997, 2024, Oracle and/or its affiliates. All rights reserved.
3 * Copyright (c) 2021, Azul Systems, Inc. All rights reserved.
4 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
5 *
6 * This code is free software; you can redistribute it and/or modify it
7 * under the terms of the GNU General Public License version 2 only, as
8 * published by the Free Software Foundation.
9 *
10 * This code is distributed in the hope that it will be useful, but WITHOUT
11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
13 * version 2 for more details (a copy is included in the LICENSE file that
14 * accompanied this code).
15 *
16 * You should have received a copy of the GNU General Public License version
17 * 2 along with this work; if not, write to the Free Software Foundation,
18 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
19 *
20 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
21 * or visit www.oracle.com if you need additional information or have any
22 * questions.
23 *
24 */
25
26 #ifndef SHARE_RUNTIME_JAVATHREAD_HPP
27 #define SHARE_RUNTIME_JAVATHREAD_HPP
28
29 #include "jni.h"
30 #include "memory/allocation.hpp"
31 #include "oops/oop.hpp"
32 #include "oops/oopHandle.hpp"
33 #include "runtime/frame.hpp"
34 #include "runtime/globals.hpp"
35 #include "runtime/handshake.hpp"
36 #include "runtime/javaFrameAnchor.hpp"
37 #include "runtime/lockStack.hpp"
38 #include "runtime/park.hpp"
39 #include "runtime/safepointMechanism.hpp"
40 #include "runtime/stackWatermarkSet.hpp"
41 #include "runtime/stackOverflow.hpp"
42 #include "runtime/thread.hpp"
43 #include "runtime/threadHeapSampler.hpp"
44 #include "runtime/threadStatisticalInfo.hpp"
45 #include "utilities/exceptions.hpp"
46 #include "utilities/globalDefinitions.hpp"
47 #include "utilities/macros.hpp"
48 #if INCLUDE_JFR
49 #include "jfr/support/jfrThreadExtension.hpp"
50 #endif
51
52 class AsyncExceptionHandshake;
53 class ContinuationEntry;
54 class DeoptResourceMark;
55 class JNIHandleBlock;
56 class JVMCIRuntime;
57
58 class JvmtiDeferredUpdates;
59 class JvmtiSampledObjectAllocEventCollector;
60 class JvmtiThreadState;
61
62 class Metadata;
63 class ObjectMonitor;
64 class OopHandleList;
65 class OopStorage;
66 class OSThread;
67
68 class ThreadsList;
69 class ThreadSafepointState;
70 class ThreadStatistics;
71
72 class vframeArray;
73 class vframe;
74 class javaVFrame;
75
76 class JavaThread;
77 typedef void (*ThreadFunction)(JavaThread*, TRAPS);
78
79 class JavaThread: public Thread {
80 friend class VMStructs;
81 friend class JVMCIVMStructs;
82 friend class WhiteBox;
83 friend class ThreadsSMRSupport; // to access _threadObj for exiting_threads_oops_do
84 friend class HandshakeState;
85 friend class Continuation;
86 friend class Threads;
87 friend class ServiceThread; // for deferred OopHandle release access
88 private:
89 bool _on_thread_list; // Is set when this JavaThread is added to the Threads list
90
91 // All references to Java objects managed via OopHandles. These
92 // have to be released by the ServiceThread after the JavaThread has
93 // terminated - see add_oop_handles_for_release().
94 OopHandle _threadObj; // The Java level thread object
95 OopHandle _vthread; // the value returned by Thread.currentThread(): the virtual thread, if mounted, otherwise _threadObj
96 OopHandle _jvmti_vthread;
97 OopHandle _scopedValueCache;
98
99 static OopStorage* _thread_oop_storage;
100
101 #ifdef ASSERT
102 private:
103 int _java_call_counter;
104
105 public:
106 int java_call_counter() { return _java_call_counter; }
107 void inc_java_call_counter() { _java_call_counter++; }
108 void dec_java_call_counter() {
109 assert(_java_call_counter > 0, "Invalid nesting of JavaCallWrapper");
110 _java_call_counter--;
111 }
112 private: // restore original namespace restriction
113 #endif // ifdef ASSERT
114
115 JavaFrameAnchor _anchor; // Encapsulation of current java frame and it state
116
117 ThreadFunction _entry_point;
118
119 JNIEnv _jni_environment;
120
121 // Deopt support
122 DeoptResourceMark* _deopt_mark; // Holds special ResourceMark for deoptimization
123
124 nmethod* _deopt_nmethod; // nmethod that is currently being deoptimized
125 vframeArray* _vframe_array_head; // Holds the heap of the active vframeArrays
126 vframeArray* _vframe_array_last; // Holds last vFrameArray we popped
127 // Holds updates by JVMTI agents for compiled frames that cannot be performed immediately. They
128 // will be carried out as soon as possible which, in most cases, is just before deoptimization of
129 // the frame, when control returns to it.
130 JvmtiDeferredUpdates* _jvmti_deferred_updates;
131
132 // Handshake value for fixing 6243940. We need a place for the i2c
133 // adapter to store the callee Method*. This value is NEVER live
134 // across a gc point so it does NOT have to be gc'd
135 // The handshake is open ended since we can't be certain that it will
136 // be nulled. This is because we rarely ever see the race and end up
137 // in handle_wrong_method which is the backend of the handshake. See
138 // code in i2c adapters and handle_wrong_method.
139
140 Method* _callee_target;
141
142 // Used to pass back results to the interpreter or generated code running Java code.
143 oop _vm_result; // oop result is GC-preserved
144 Metadata* _vm_result_2; // non-oop result
145
146 // See ReduceInitialCardMarks: this holds the precise space interval of
147 // the most recent slow path allocation for which compiled code has
148 // elided card-marks for performance along the fast-path.
149 MemRegion _deferred_card_mark;
150
151 ObjectMonitor* volatile _current_pending_monitor; // ObjectMonitor this thread is waiting to lock
152 bool _current_pending_monitor_is_from_java; // locking is from Java code
153 ObjectMonitor* volatile _current_waiting_monitor; // ObjectMonitor on which this thread called Object.wait()
154
155 // Active_handles points to a block of handles
156 JNIHandleBlock* _active_handles;
157
158 // One-element thread local free list
159 JNIHandleBlock* _free_handle_block;
160
161 public:
162 // For tracking the heavyweight monitor the thread is pending on.
163 ObjectMonitor* current_pending_monitor() {
164 // Use Atomic::load() to prevent data race between concurrent modification and
165 // concurrent readers, e.g. ThreadService::get_current_contended_monitor().
166 // Especially, reloading pointer from thread after null check must be prevented.
167 return Atomic::load(&_current_pending_monitor);
168 }
169 void set_current_pending_monitor(ObjectMonitor* monitor) {
170 Atomic::store(&_current_pending_monitor, monitor);
171 }
172 void set_current_pending_monitor_is_from_java(bool from_java) {
173 _current_pending_monitor_is_from_java = from_java;
174 }
175 bool current_pending_monitor_is_from_java() {
176 return _current_pending_monitor_is_from_java;
177 }
178 ObjectMonitor* current_waiting_monitor() {
179 // See the comment in current_pending_monitor() above.
180 return Atomic::load(&_current_waiting_monitor);
181 }
182 void set_current_waiting_monitor(ObjectMonitor* monitor) {
183 Atomic::store(&_current_waiting_monitor, monitor);
184 }
185
186 // JNI handle support
187 JNIHandleBlock* active_handles() const { return _active_handles; }
188 void set_active_handles(JNIHandleBlock* block) { _active_handles = block; }
189 JNIHandleBlock* free_handle_block() const { return _free_handle_block; }
190 void set_free_handle_block(JNIHandleBlock* block) { _free_handle_block = block; }
191
192 void push_jni_handle_block();
193 void pop_jni_handle_block();
194
195 private:
196 MonitorChunk* _monitor_chunks; // Contains the off stack monitors
197 // allocated during deoptimization
198 // and by JNI_MonitorEnter/Exit
199
200 enum SuspendFlags {
201 // NOTE: avoid using the sign-bit as cc generates different test code
202 // when the sign-bit is used, and sometimes incorrectly - see CR 6398077
203 _trace_flag = 0x00000004U, // call tracing backend
204 _obj_deopt = 0x00000008U // suspend for object reallocation and relocking for JVMTI agent
205 };
206
207 // various suspension related flags - atomically updated
208 volatile uint32_t _suspend_flags;
209
210 inline void set_suspend_flag(SuspendFlags f);
211 inline void clear_suspend_flag(SuspendFlags f);
212
213 public:
214 inline void set_trace_flag();
215 inline void clear_trace_flag();
216 inline void set_obj_deopt_flag();
217 inline void clear_obj_deopt_flag();
218 bool is_trace_suspend() { return (_suspend_flags & _trace_flag) != 0; }
219 bool is_obj_deopt_suspend() { return (_suspend_flags & _obj_deopt) != 0; }
220
221 // Asynchronous exception support
222 private:
223 friend class InstallAsyncExceptionHandshake;
224 friend class AsyncExceptionHandshake;
225 friend class HandshakeState;
226
227 void handle_async_exception(oop java_throwable);
228 public:
229 void install_async_exception(AsyncExceptionHandshake* aec = nullptr);
230 bool has_async_exception_condition();
231 inline void set_pending_unsafe_access_error();
232 static void send_async_exception(JavaThread* jt, oop java_throwable);
233
234 class NoAsyncExceptionDeliveryMark : public StackObj {
235 friend JavaThread;
236 JavaThread *_target;
237 inline NoAsyncExceptionDeliveryMark(JavaThread *t);
238 inline ~NoAsyncExceptionDeliveryMark();
239 };
240
241 // Safepoint support
242 public: // Expose _thread_state for SafeFetchInt()
243 volatile JavaThreadState _thread_state;
244 private:
245 SafepointMechanism::ThreadData _poll_data;
246 ThreadSafepointState* _safepoint_state; // Holds information about a thread during a safepoint
247 address _saved_exception_pc; // Saved pc of instruction where last implicit exception happened
248 NOT_PRODUCT(bool _requires_cross_modify_fence;) // State used by VerifyCrossModifyFence
249 #ifdef ASSERT
250 // Debug support for checking if code allows safepoints or not.
251 // Safepoints in the VM can happen because of allocation, invoking a VM operation, or blocking on
252 // mutex, or blocking on an object synchronizer (Java locking).
253 // If _no_safepoint_count is non-zero, then an assertion failure will happen in any of
254 // the above cases. The class NoSafepointVerifier is used to set this counter.
255 int _no_safepoint_count; // If 0, thread allow a safepoint to happen
256
257 public:
258 void inc_no_safepoint_count() { _no_safepoint_count++; }
259 void dec_no_safepoint_count() { _no_safepoint_count--; }
260 bool is_in_no_safepoint_scope() { return _no_safepoint_count > 0; }
261 #endif // ASSERT
262 public:
263 // These functions check conditions before possibly going to a safepoint.
264 // including NoSafepointVerifier.
265 void check_for_valid_safepoint_state() NOT_DEBUG_RETURN;
266 void check_possible_safepoint() NOT_DEBUG_RETURN;
267
268 #ifdef ASSERT
269 private:
270 volatile uint64_t _visited_for_critical_count;
271
272 public:
273 void set_visited_for_critical_count(uint64_t safepoint_id) {
274 assert(_visited_for_critical_count == 0, "Must be reset before set");
275 assert((safepoint_id & 0x1) == 1, "Must be odd");
276 _visited_for_critical_count = safepoint_id;
277 }
278 void reset_visited_for_critical_count(uint64_t safepoint_id) {
279 assert(_visited_for_critical_count == safepoint_id, "Was not visited");
280 _visited_for_critical_count = 0;
281 }
282 bool was_visited_for_critical_count(uint64_t safepoint_id) const {
283 return _visited_for_critical_count == safepoint_id;
284 }
285 #endif // ASSERT
286
287 // JavaThread termination support
288 public:
289 enum TerminatedTypes {
290 _not_terminated = 0xDEAD - 3,
291 _thread_exiting, // JavaThread::exit() has been called for this thread
292 _thread_gc_barrier_detached, // thread's GC barrier has been detached
293 _thread_terminated, // JavaThread is removed from thread list
294 _vm_exited // JavaThread is still executing native code, but VM is terminated
295 // only VM_Exit can set _vm_exited
296 };
297
298 private:
299 // In general a JavaThread's _terminated field transitions as follows:
300 //
301 // _not_terminated => _thread_exiting => _thread_gc_barrier_detached => _thread_terminated
302 //
303 // _vm_exited is a special value to cover the case of a JavaThread
304 // executing native code after the VM itself is terminated.
305 //
306 // A JavaThread that fails to JNI attach has these _terminated field transitions:
307 // _not_terminated => _thread_terminated
308 //
309 volatile TerminatedTypes _terminated;
310
311 jint _in_deopt_handler; // count of deoptimization
312 // handlers thread is in
313 volatile bool _doing_unsafe_access; // Thread may fault due to unsafe access
314 bool _do_not_unlock_if_synchronized; // Do not unlock the receiver of a synchronized method (since it was
315 // never locked) when throwing an exception. Used by interpreter only.
316 #if INCLUDE_JVMTI
317 volatile bool _carrier_thread_suspended; // Carrier thread is externally suspended
318 bool _is_in_VTMS_transition; // thread is in virtual thread mount state transition
319 bool _is_in_tmp_VTMS_transition; // thread is in temporary virtual thread mount state transition
320 bool _is_disable_suspend; // JVMTI suspend is temporarily disabled; used on current thread only
321 #ifdef ASSERT
322 bool _is_VTMS_transition_disabler; // thread currently disabled VTMS transitions
323 #endif
324 #endif
325
326 // JNI attach states:
327 enum JNIAttachStates {
328 _not_attaching_via_jni = 1, // thread is not attaching via JNI
329 _attaching_via_jni, // thread is attaching via JNI
330 _attached_via_jni // thread has attached via JNI
331 };
332
333 // A regular JavaThread's _jni_attach_state is _not_attaching_via_jni.
334 // A native thread that is attaching via JNI starts with a value
335 // of _attaching_via_jni and transitions to _attached_via_jni.
336 volatile JNIAttachStates _jni_attach_state;
337
338
339 #if INCLUDE_JVMCI
340 // The _pending_* fields below are used to communicate extra information
341 // from an uncommon trap in JVMCI compiled code to the uncommon trap handler.
342
343 // Communicates the DeoptReason and DeoptAction of the uncommon trap
344 int _pending_deoptimization;
345
346 // Specifies whether the uncommon trap is to bci 0 of a synchronized method
347 // before the monitor has been acquired.
348 bool _pending_monitorenter;
349
350 // Specifies if the DeoptReason for the last uncommon trap was Reason_transfer_to_interpreter
351 bool _pending_transfer_to_interpreter;
352
353 // True if in a runtime call from compiled code that will deoptimize
354 // and re-execute a failed heap allocation in the interpreter.
355 bool _in_retryable_allocation;
356
357 // An id of a speculation that JVMCI compiled code can use to further describe and
358 // uniquely identify the speculative optimization guarded by an uncommon trap.
359 // See JVMCINMethodData::SPECULATION_LENGTH_BITS for further details.
360 jlong _pending_failed_speculation;
361
362 // These fields are mutually exclusive in terms of live ranges.
363 union {
364 // Communicates the pc at which the most recent implicit exception occurred
365 // from the signal handler to a deoptimization stub.
366 address _implicit_exception_pc;
367
368 // Communicates an alternative call target to an i2c stub from a JavaCall .
369 address _alternate_call_target;
370 } _jvmci;
371
372 // The JVMCIRuntime in a JVMCI shared library
373 JVMCIRuntime* _libjvmci_runtime;
374
375 // Support for high precision, thread sensitive counters in JVMCI compiled code.
376 jlong* _jvmci_counters;
377
378 // Fast thread locals for use by JVMCI
379 jlong _jvmci_reserved0;
380 jlong _jvmci_reserved1;
381 oop _jvmci_reserved_oop0;
382
383 public:
384 static jlong* _jvmci_old_thread_counters;
385 static void collect_counters(jlong* array, int length);
386
387 bool resize_counters(int current_size, int new_size);
388
389 static bool resize_all_jvmci_counters(int new_size);
390
391 void set_jvmci_reserved_oop0(oop value) {
392 _jvmci_reserved_oop0 = value;
393 }
394
395 oop get_jvmci_reserved_oop0() {
396 return _jvmci_reserved_oop0;
397 }
398
399 void set_jvmci_reserved0(jlong value) {
400 _jvmci_reserved0 = value;
401 }
402
403 jlong get_jvmci_reserved0() {
404 return _jvmci_reserved0;
405 }
406
407 void set_jvmci_reserved1(jlong value) {
408 _jvmci_reserved1 = value;
409 }
410
411 jlong get_jvmci_reserved1() {
412 return _jvmci_reserved1;
413 }
414
415 private:
416 #endif // INCLUDE_JVMCI
417
418 StackOverflow _stack_overflow_state;
419
420 void pretouch_stack();
421
422 // Compiler exception handling (NOTE: The _exception_oop is *NOT* the same as _pending_exception. It is
423 // used to temp. parsing values into and out of the runtime system during exception handling for compiled
424 // code)
425 volatile oop _exception_oop; // Exception thrown in compiled code
426 volatile address _exception_pc; // PC where exception happened
427 volatile address _exception_handler_pc; // PC for handler of exception
428 volatile int _is_method_handle_return; // true (== 1) if the current exception PC is a MethodHandle call site.
429
430 private:
431 // support for JNI critical regions
432 jint _jni_active_critical; // count of entries into JNI critical region
433
434 // Checked JNI: function name requires exception check
435 char* _pending_jni_exception_check_fn;
436
437 // For deadlock detection.
438 int _depth_first_number;
439
440 // JVMTI PopFrame support
441 // This is set to popframe_pending to signal that top Java frame should be popped immediately
442 int _popframe_condition;
443
444 // If reallocation of scalar replaced objects fails, we throw OOM
445 // and during exception propagation, pop the top
446 // _frames_to_pop_failed_realloc frames, the ones that reference
447 // failed reallocations.
448 int _frames_to_pop_failed_realloc;
449
450 ContinuationEntry* _cont_entry;
451 intptr_t* _cont_fastpath; // the sp of the oldest known interpreted/call_stub frame inside the
452 // continuation that we know about
453 int _cont_fastpath_thread_state; // whether global thread state allows continuation fastpath (JVMTI)
454
455 // It's signed for error detection.
456 intx _held_monitor_count; // used by continuations for fast lock detection
457 intx _jni_monitor_count;
458
459 private:
460
461 friend class VMThread;
462 friend class ThreadWaitTransition;
463 friend class VM_Exit;
464
465 // Stack watermark barriers.
466 StackWatermarks _stack_watermarks;
467
468 public:
469 inline StackWatermarks* stack_watermarks() { return &_stack_watermarks; }
470
471 public:
472 // Constructor
473 JavaThread(); // delegating constructor
474 JavaThread(bool is_attaching_via_jni); // for main thread and JNI attached threads
475 JavaThread(ThreadFunction entry_point, size_t stack_size = 0);
476 ~JavaThread();
477
478 #ifdef ASSERT
479 // verify this JavaThread hasn't be published in the Threads::list yet
480 void verify_not_published();
481 #endif // ASSERT
482
483 StackOverflow* stack_overflow_state() { return &_stack_overflow_state; }
484
485 //JNI functiontable getter/setter for JVMTI jni function table interception API.
486 void set_jni_functions(struct JNINativeInterface_* functionTable) {
487 _jni_environment.functions = functionTable;
488 }
489 struct JNINativeInterface_* get_jni_functions() {
490 return (struct JNINativeInterface_ *)_jni_environment.functions;
491 }
492
493 // This function is called at thread creation to allow
494 // platform specific thread variables to be initialized.
495 void cache_global_variables();
496
497 // Executes Shutdown.shutdown()
498 void invoke_shutdown_hooks();
499
500 // Cleanup on thread exit
501 enum ExitType {
502 normal_exit,
503 jni_detach
504 };
505 void exit(bool destroy_vm, ExitType exit_type = normal_exit);
506
507 void cleanup_failed_attach_current_thread(bool is_daemon);
508
509 // Testers
510 virtual bool is_Java_thread() const { return true; }
511 virtual bool can_call_java() const { return true; }
512
513 virtual bool is_active_Java_thread() const;
514
515 // Thread oop. threadObj() can be null for initial JavaThread
516 // (or for threads attached via JNI)
517 oop threadObj() const;
518 void set_threadOopHandles(oop p);
519 oop vthread() const;
520 void set_vthread(oop p);
521 oop scopedValueCache() const;
522 void set_scopedValueCache(oop p);
523 void clear_scopedValueBindings();
524 oop jvmti_vthread() const;
525 void set_jvmti_vthread(oop p);
526 oop vthread_or_thread() const;
527
528 // Prepare thread and add to priority queue. If a priority is
529 // not specified, use the priority of the thread object. Threads_lock
530 // must be held while this function is called.
531 void prepare(jobject jni_thread, ThreadPriority prio=NoPriority);
532
533 void set_saved_exception_pc(address pc) { _saved_exception_pc = pc; }
534 address saved_exception_pc() { return _saved_exception_pc; }
535
536 ThreadFunction entry_point() const { return _entry_point; }
537
538 // Allocates a new Java level thread object for this thread. thread_name may be null.
539 void allocate_threadObj(Handle thread_group, const char* thread_name, bool daemon, TRAPS);
540
541 // Last frame anchor routines
542
543 JavaFrameAnchor* frame_anchor(void) { return &_anchor; }
544
545 // last_Java_sp
546 bool has_last_Java_frame() const { return _anchor.has_last_Java_frame(); }
547 intptr_t* last_Java_sp() const { return _anchor.last_Java_sp(); }
548
549 // last_Java_pc
550
551 address last_Java_pc(void) { return _anchor.last_Java_pc(); }
552
553 // Safepoint support
554 inline JavaThreadState thread_state() const;
555 inline void set_thread_state(JavaThreadState s);
556 inline void set_thread_state_fence(JavaThreadState s); // fence after setting thread state
557 inline ThreadSafepointState* safepoint_state() const;
558 inline void set_safepoint_state(ThreadSafepointState* state);
559 inline bool is_at_poll_safepoint();
560
561 // JavaThread termination and lifecycle support:
562 void smr_delete();
563 bool on_thread_list() const { return _on_thread_list; }
564 void set_on_thread_list() { _on_thread_list = true; }
565
566 // thread has called JavaThread::exit(), thread's GC barrier is detached
567 // or thread is terminated
568 bool is_exiting() const;
569 // thread's GC barrier is NOT detached and thread is NOT terminated
570 bool is_oop_safe() const;
571 // thread is terminated (no longer on the threads list); the thread must
572 // be protected by a ThreadsListHandle to avoid potential crashes.
573 bool check_is_terminated(TerminatedTypes l_terminated) const {
574 return l_terminated == _thread_terminated || l_terminated == _vm_exited;
575 }
576 bool is_terminated() const;
577 void set_terminated(TerminatedTypes t);
578
579 void block_if_vm_exited();
580
581 bool doing_unsafe_access() { return _doing_unsafe_access; }
582 void set_doing_unsafe_access(bool val) { _doing_unsafe_access = val; }
583
584 bool do_not_unlock_if_synchronized() { return _do_not_unlock_if_synchronized; }
585 void set_do_not_unlock_if_synchronized(bool val) { _do_not_unlock_if_synchronized = val; }
586
587 SafepointMechanism::ThreadData* poll_data() { return &_poll_data; }
588
589 void set_requires_cross_modify_fence(bool val) PRODUCT_RETURN NOT_PRODUCT({ _requires_cross_modify_fence = val; })
590
591 // Continuation support
592 ContinuationEntry* last_continuation() const { return _cont_entry; }
593 void set_cont_fastpath(intptr_t* x) { _cont_fastpath = x; }
594 void push_cont_fastpath(intptr_t* sp) { if (sp > _cont_fastpath) _cont_fastpath = sp; }
595 void set_cont_fastpath_thread_state(bool x) { _cont_fastpath_thread_state = (int)x; }
596 intptr_t* raw_cont_fastpath() const { return _cont_fastpath; }
597 bool cont_fastpath() const { return _cont_fastpath == nullptr && _cont_fastpath_thread_state != 0; }
598 bool cont_fastpath_thread_state() const { return _cont_fastpath_thread_state != 0; }
599
600 void inc_held_monitor_count(intx i = 1, bool jni = false);
601 void dec_held_monitor_count(intx i = 1, bool jni = false);
602
603 intx held_monitor_count() { return _held_monitor_count; }
604 intx jni_monitor_count() { return _jni_monitor_count; }
605 void clear_jni_monitor_count() { _jni_monitor_count = 0; }
606
607 inline bool is_vthread_mounted() const;
608 inline const ContinuationEntry* vthread_continuation() const;
609
610 private:
611 DEBUG_ONLY(void verify_frame_info();)
612
613 // Support for thread handshake operations
614 HandshakeState _handshake;
615 public:
616 HandshakeState* handshake_state() { return &_handshake; }
617
618 // A JavaThread can always safely operate on it self and other threads
619 // can do it safely if they are the active handshaker.
620 bool is_handshake_safe_for(Thread* th) const {
621 return _handshake.active_handshaker() == th || this == th;
622 }
623
624 // Suspend/resume support for JavaThread
625 // higher-level suspension/resume logic called by the public APIs
626 bool java_suspend();
627 bool java_resume();
628 bool is_suspended() { return _handshake.is_suspended(); }
629
630 // Check for async exception in addition to safepoint.
631 static void check_special_condition_for_native_trans(JavaThread *thread);
632
633 // Synchronize with another thread that is deoptimizing objects of the
634 // current thread, i.e. reverts optimizations based on escape analysis.
635 void wait_for_object_deoptimization();
636
637 #if INCLUDE_JVMTI
638 inline void set_carrier_thread_suspended();
639 inline void clear_carrier_thread_suspended();
640
641 bool is_carrier_thread_suspended() const {
642 return _carrier_thread_suspended;
643 }
644
645 bool is_in_VTMS_transition() const { return _is_in_VTMS_transition; }
646 bool is_in_tmp_VTMS_transition() const { return _is_in_tmp_VTMS_transition; }
647 bool is_in_any_VTMS_transition() const { return _is_in_VTMS_transition || _is_in_tmp_VTMS_transition; }
648
649 void set_is_in_VTMS_transition(bool val);
650 void toggle_is_in_tmp_VTMS_transition() { _is_in_tmp_VTMS_transition = !_is_in_tmp_VTMS_transition; };
651
652 bool is_disable_suspend() const { return _is_disable_suspend; }
653 void toggle_is_disable_suspend() { _is_disable_suspend = !_is_disable_suspend; };
654
655 #ifdef ASSERT
656 bool is_VTMS_transition_disabler() const { return _is_VTMS_transition_disabler; }
657 void set_is_VTMS_transition_disabler(bool val);
658 #endif
659 #endif
660
661 // Support for object deoptimization and JFR suspension
662 void handle_special_runtime_exit_condition();
663 bool has_special_runtime_exit_condition() {
664 return (_suspend_flags & (_obj_deopt JFR_ONLY(| _trace_flag))) != 0;
665 }
666
667 // Fast-locking support
668 bool is_lock_owned(address adr) const;
669
670 // Accessors for vframe array top
671 // The linked list of vframe arrays are sorted on sp. This means when we
672 // unpack the head must contain the vframe array to unpack.
673 void set_vframe_array_head(vframeArray* value) { _vframe_array_head = value; }
674 vframeArray* vframe_array_head() const { return _vframe_array_head; }
675
676 // Side structure for deferring update of java frame locals until deopt occurs
677 JvmtiDeferredUpdates* deferred_updates() const { return _jvmti_deferred_updates; }
678 void set_deferred_updates(JvmtiDeferredUpdates* du) { _jvmti_deferred_updates = du; }
679
680 // These only really exist to make debugging deopt problems simpler
681
682 void set_vframe_array_last(vframeArray* value) { _vframe_array_last = value; }
683 vframeArray* vframe_array_last() const { return _vframe_array_last; }
684
685 // The special resourceMark used during deoptimization
686
687 void set_deopt_mark(DeoptResourceMark* value) { _deopt_mark = value; }
688 DeoptResourceMark* deopt_mark(void) { return _deopt_mark; }
689
690 void set_deopt_compiled_method(nmethod* nm) { _deopt_nmethod = nm; }
691 nmethod* deopt_compiled_method() { return _deopt_nmethod; }
692
693 Method* callee_target() const { return _callee_target; }
694 void set_callee_target (Method* x) { _callee_target = x; }
695
696 // Oop results of vm runtime calls
697 oop vm_result() const { return _vm_result; }
698 void set_vm_result (oop x) { _vm_result = x; }
699
700 void set_vm_result_2 (Metadata* x) { _vm_result_2 = x; }
701
702 MemRegion deferred_card_mark() const { return _deferred_card_mark; }
703 void set_deferred_card_mark(MemRegion mr) { _deferred_card_mark = mr; }
704
705 #if INCLUDE_JVMCI
706 jlong pending_failed_speculation() const { return _pending_failed_speculation; }
707 void set_pending_monitorenter(bool b) { _pending_monitorenter = b; }
708 void set_pending_deoptimization(int reason) { _pending_deoptimization = reason; }
709 void set_pending_failed_speculation(jlong failed_speculation) { _pending_failed_speculation = failed_speculation; }
710 void set_pending_transfer_to_interpreter(bool b) { _pending_transfer_to_interpreter = b; }
711 void set_jvmci_alternate_call_target(address a) { assert(_jvmci._alternate_call_target == nullptr, "must be"); _jvmci._alternate_call_target = a; }
712 void set_jvmci_implicit_exception_pc(address a) { assert(_jvmci._implicit_exception_pc == nullptr, "must be"); _jvmci._implicit_exception_pc = a; }
713
714 virtual bool in_retryable_allocation() const { return _in_retryable_allocation; }
715 void set_in_retryable_allocation(bool b) { _in_retryable_allocation = b; }
716
717 JVMCIRuntime* libjvmci_runtime() const { return _libjvmci_runtime; }
718 void set_libjvmci_runtime(JVMCIRuntime* rt) {
719 assert((_libjvmci_runtime == nullptr && rt != nullptr) || (_libjvmci_runtime != nullptr && rt == nullptr), "must be");
720 _libjvmci_runtime = rt;
721 }
722 #endif // INCLUDE_JVMCI
723
724 // Exception handling for compiled methods
725 oop exception_oop() const;
726 address exception_pc() const { return _exception_pc; }
727
728 void set_exception_oop(oop o);
729 void set_exception_pc(address a) { _exception_pc = a; }
730 void set_exception_handler_pc(address a) { _exception_handler_pc = a; }
731 void set_is_method_handle_return(bool value) { _is_method_handle_return = value ? 1 : 0; }
732
733 void clear_exception_oop_and_pc() {
734 set_exception_oop(nullptr);
735 set_exception_pc(nullptr);
736 }
737
738 // Check if address is in the usable part of the stack (excludes protected
739 // guard pages). Can be applied to any thread and is an approximation for
740 // using is_in_live_stack when the query has to happen from another thread.
741 bool is_in_usable_stack(address adr) const {
742 return is_in_stack_range_incl(adr, _stack_overflow_state.stack_reserved_zone_base());
743 }
744
745 // Misc. accessors/mutators
746 static ByteSize scopedValueCache_offset() { return byte_offset_of(JavaThread, _scopedValueCache); }
747
748 // For assembly stub generation
749 static ByteSize threadObj_offset() { return byte_offset_of(JavaThread, _threadObj); }
750 static ByteSize vthread_offset() { return byte_offset_of(JavaThread, _vthread); }
751 static ByteSize jni_environment_offset() { return byte_offset_of(JavaThread, _jni_environment); }
752 static ByteSize pending_jni_exception_check_fn_offset() {
753 return byte_offset_of(JavaThread, _pending_jni_exception_check_fn);
754 }
755 static ByteSize last_Java_sp_offset() {
756 return byte_offset_of(JavaThread, _anchor) + JavaFrameAnchor::last_Java_sp_offset();
757 }
758 static ByteSize last_Java_pc_offset() {
759 return byte_offset_of(JavaThread, _anchor) + JavaFrameAnchor::last_Java_pc_offset();
760 }
761 static ByteSize frame_anchor_offset() {
762 return byte_offset_of(JavaThread, _anchor);
763 }
764 static ByteSize callee_target_offset() { return byte_offset_of(JavaThread, _callee_target); }
765 static ByteSize vm_result_offset() { return byte_offset_of(JavaThread, _vm_result); }
766 static ByteSize vm_result_2_offset() { return byte_offset_of(JavaThread, _vm_result_2); }
767 static ByteSize thread_state_offset() { return byte_offset_of(JavaThread, _thread_state); }
768 static ByteSize polling_word_offset() { return byte_offset_of(JavaThread, _poll_data) + byte_offset_of(SafepointMechanism::ThreadData, _polling_word);}
769 static ByteSize polling_page_offset() { return byte_offset_of(JavaThread, _poll_data) + byte_offset_of(SafepointMechanism::ThreadData, _polling_page);}
770 static ByteSize saved_exception_pc_offset() { return byte_offset_of(JavaThread, _saved_exception_pc); }
771 static ByteSize osthread_offset() { return byte_offset_of(JavaThread, _osthread); }
772 #if INCLUDE_JVMCI
773 static ByteSize pending_deoptimization_offset() { return byte_offset_of(JavaThread, _pending_deoptimization); }
774 static ByteSize pending_monitorenter_offset() { return byte_offset_of(JavaThread, _pending_monitorenter); }
775 static ByteSize jvmci_alternate_call_target_offset() { return byte_offset_of(JavaThread, _jvmci._alternate_call_target); }
776 static ByteSize jvmci_implicit_exception_pc_offset() { return byte_offset_of(JavaThread, _jvmci._implicit_exception_pc); }
777 static ByteSize jvmci_counters_offset() { return byte_offset_of(JavaThread, _jvmci_counters); }
778 #endif // INCLUDE_JVMCI
779 static ByteSize exception_oop_offset() { return byte_offset_of(JavaThread, _exception_oop); }
780 static ByteSize exception_pc_offset() { return byte_offset_of(JavaThread, _exception_pc); }
781 static ByteSize exception_handler_pc_offset() { return byte_offset_of(JavaThread, _exception_handler_pc); }
782 static ByteSize is_method_handle_return_offset() { return byte_offset_of(JavaThread, _is_method_handle_return); }
783
784 static ByteSize active_handles_offset() { return byte_offset_of(JavaThread, _active_handles); }
785
786 // StackOverflow offsets
787 static ByteSize stack_overflow_limit_offset() {
788 return byte_offset_of(JavaThread, _stack_overflow_state._stack_overflow_limit);
789 }
790 static ByteSize stack_guard_state_offset() {
791 return byte_offset_of(JavaThread, _stack_overflow_state._stack_guard_state);
792 }
793 static ByteSize reserved_stack_activation_offset() {
794 return byte_offset_of(JavaThread, _stack_overflow_state._reserved_stack_activation);
795 }
796 static ByteSize shadow_zone_safe_limit() {
797 return byte_offset_of(JavaThread, _stack_overflow_state._shadow_zone_safe_limit);
798 }
799 static ByteSize shadow_zone_growth_watermark() {
800 return byte_offset_of(JavaThread, _stack_overflow_state._shadow_zone_growth_watermark);
801 }
802
803 static ByteSize suspend_flags_offset() { return byte_offset_of(JavaThread, _suspend_flags); }
804
805 static ByteSize do_not_unlock_if_synchronized_offset() { return byte_offset_of(JavaThread, _do_not_unlock_if_synchronized); }
806 static ByteSize should_post_on_exceptions_flag_offset() {
807 return byte_offset_of(JavaThread, _should_post_on_exceptions_flag);
808 }
809 static ByteSize doing_unsafe_access_offset() { return byte_offset_of(JavaThread, _doing_unsafe_access); }
810 NOT_PRODUCT(static ByteSize requires_cross_modify_fence_offset() { return byte_offset_of(JavaThread, _requires_cross_modify_fence); })
811
812 static ByteSize cont_entry_offset() { return byte_offset_of(JavaThread, _cont_entry); }
813 static ByteSize cont_fastpath_offset() { return byte_offset_of(JavaThread, _cont_fastpath); }
814 static ByteSize held_monitor_count_offset() { return byte_offset_of(JavaThread, _held_monitor_count); }
815
816 #if INCLUDE_JVMTI
817 static ByteSize is_in_VTMS_transition_offset() { return byte_offset_of(JavaThread, _is_in_VTMS_transition); }
818 static ByteSize is_in_tmp_VTMS_transition_offset() { return byte_offset_of(JavaThread, _is_in_tmp_VTMS_transition); }
819 static ByteSize is_disable_suspend_offset() { return byte_offset_of(JavaThread, _is_disable_suspend); }
820 #endif
821
822 // Returns the jni environment for this thread
823 JNIEnv* jni_environment() { return &_jni_environment; }
824
825 // Returns the current thread as indicated by the given JNIEnv.
826 // We don't assert it is Thread::current here as that is done at the
827 // external JNI entry points where the JNIEnv is passed into the VM.
828 static JavaThread* thread_from_jni_environment(JNIEnv* env) {
829 JavaThread* current = reinterpret_cast<JavaThread*>(((intptr_t)env - in_bytes(jni_environment_offset())));
830 // We can't normally get here in a thread that has completed its
831 // execution and so "is_terminated", except when the call is from
832 // AsyncGetCallTrace, which can be triggered by a signal at any point in
833 // a thread's lifecycle. A thread is also considered terminated if the VM
834 // has exited, so we have to check this and block in case this is a daemon
835 // thread returning to the VM (the JNI DirectBuffer entry points rely on
836 // this).
837 if (current->is_terminated()) {
838 current->block_if_vm_exited();
839 }
840 return current;
841 }
842
843 // JNI critical regions. These can nest.
844 bool in_critical() { return _jni_active_critical > 0; }
845 bool in_last_critical() { return _jni_active_critical == 1; }
846 inline void enter_critical();
847 void exit_critical() {
848 assert(Thread::current() == this, "this must be current thread");
849 _jni_active_critical--;
850 assert(_jni_active_critical >= 0, "JNI critical nesting problem?");
851 }
852
853 // Checked JNI: is the programmer required to check for exceptions, if so specify
854 // which function name. Returning to a Java frame should implicitly clear the
855 // pending check, this is done for Native->Java transitions (i.e. user JNI code).
856 // VM->Java transitions are not cleared, it is expected that JNI code enclosed
857 // within ThreadToNativeFromVM makes proper exception checks (i.e. VM internal).
858 bool is_pending_jni_exception_check() const { return _pending_jni_exception_check_fn != nullptr; }
859 void clear_pending_jni_exception_check() { _pending_jni_exception_check_fn = nullptr; }
860 const char* get_pending_jni_exception_check() const { return _pending_jni_exception_check_fn; }
861 void set_pending_jni_exception_check(const char* fn_name) { _pending_jni_exception_check_fn = (char*) fn_name; }
862
863 // For deadlock detection
864 int depth_first_number() { return _depth_first_number; }
865 void set_depth_first_number(int dfn) { _depth_first_number = dfn; }
866
867 private:
868 void set_monitor_chunks(MonitorChunk* monitor_chunks) { _monitor_chunks = monitor_chunks; }
869
870 public:
871 MonitorChunk* monitor_chunks() const { return _monitor_chunks; }
872 void add_monitor_chunk(MonitorChunk* chunk);
873 void remove_monitor_chunk(MonitorChunk* chunk);
874 bool in_deopt_handler() const { return _in_deopt_handler > 0; }
875 void inc_in_deopt_handler() { _in_deopt_handler++; }
876 void dec_in_deopt_handler() {
877 assert(_in_deopt_handler > 0, "mismatched deopt nesting");
878 if (_in_deopt_handler > 0) { // robustness
879 _in_deopt_handler--;
880 }
881 }
882
883 private:
884 void set_entry_point(ThreadFunction entry_point) { _entry_point = entry_point; }
885
886 // factor out low-level mechanics for use in both normal and error cases
887 const char* get_thread_name_string(char* buf = nullptr, int buflen = 0) const;
888
889 public:
890
891 // Frame iteration; calls the function f for all frames on the stack
892 void frames_do(void f(frame*, const RegisterMap*));
893
894 // Memory operations
895 void oops_do_frames(OopClosure* f, NMethodClosure* cf);
896 void oops_do_no_frames(OopClosure* f, NMethodClosure* cf);
897
898 // GC operations
899 virtual void nmethods_do(NMethodClosure* cf);
900
901 // RedefineClasses Support
902 void metadata_do(MetadataClosure* f);
903
904 // Debug method asserting thread states are correct during a handshake operation.
905 DEBUG_ONLY(void verify_states_for_handshake();)
906
907 // Misc. operations
908 const char* name() const;
909 const char* name_raw() const;
910 const char* type_name() const { return "JavaThread"; }
911 static const char* name_for(oop thread_obj);
912
913 void print_on(outputStream* st, bool print_extended_info) const;
914 void print_on(outputStream* st) const { print_on(st, false); }
915 void print() const;
916 void print_thread_state_on(outputStream*) const;
917 void print_on_error(outputStream* st, char* buf, int buflen) const;
918 void print_name_on_error(outputStream* st, char* buf, int buflen) const;
919 void verify();
920
921 // Accessing frames
922 frame last_frame() {
923 _anchor.make_walkable();
924 return pd_last_frame();
925 }
926 javaVFrame* last_java_vframe(RegisterMap* reg_map) { return last_java_vframe(last_frame(), reg_map); }
927
928 frame carrier_last_frame(RegisterMap* reg_map);
929 javaVFrame* carrier_last_java_vframe(RegisterMap* reg_map) { return last_java_vframe(carrier_last_frame(reg_map), reg_map); }
930
931 frame vthread_last_frame();
932 javaVFrame* vthread_last_java_vframe(RegisterMap* reg_map) { return last_java_vframe(vthread_last_frame(), reg_map); }
933
934 frame platform_thread_last_frame(RegisterMap* reg_map);
935 javaVFrame* platform_thread_last_java_vframe(RegisterMap* reg_map) {
936 return last_java_vframe(platform_thread_last_frame(reg_map), reg_map);
937 }
938
939 javaVFrame* last_java_vframe(const frame f, RegisterMap* reg_map);
940
941 // Returns method at 'depth' java or native frames down the stack
942 // Used for security checks
943 Klass* security_get_caller_class(int depth);
944
945 // Print stack trace in external format
946 // These variants print carrier/platform thread information only.
947 void print_stack_on(outputStream* st);
948 void print_stack() { print_stack_on(tty); }
949 // This prints the currently mounted virtual thread.
950 void print_vthread_stack_on(outputStream* st);
951 // This prints the active stack: either carrier/platform or virtual.
952 void print_active_stack_on(outputStream* st);
953 // Print current stack trace for checked JNI warnings and JNI fatal errors.
954 // This is the external format from above, but selecting the platform
955 // or vthread as applicable.
956 void print_jni_stack();
957
958 // Print stack traces in various internal formats
959 void trace_stack() PRODUCT_RETURN;
960 void trace_stack_from(vframe* start_vf) PRODUCT_RETURN;
961 void trace_frames() PRODUCT_RETURN;
962
963 // Print an annotated view of the stack frames
964 void print_frame_layout(int depth = 0, bool validate_only = false) NOT_DEBUG_RETURN;
965 void validate_frame_layout() {
966 print_frame_layout(0, true);
967 }
968
969 // Function for testing deoptimization
970 void deoptimize();
971 void make_zombies();
972
973 void deoptimize_marked_methods();
974
975 public:
976 // Returns the running thread as a JavaThread
977 static JavaThread* current() {
978 return JavaThread::cast(Thread::current());
979 }
980
981 // Returns the current thread as a JavaThread, or nullptr if not attached
982 static inline JavaThread* current_or_null();
983
984 // Casts
985 static JavaThread* cast(Thread* t) {
986 assert(t->is_Java_thread(), "incorrect cast to JavaThread");
987 return static_cast<JavaThread*>(t);
988 }
989
990 static const JavaThread* cast(const Thread* t) {
991 assert(t->is_Java_thread(), "incorrect cast to const JavaThread");
992 return static_cast<const JavaThread*>(t);
993 }
994
995 // Returns the active Java thread. Do not use this if you know you are calling
996 // from a JavaThread, as it's slower than JavaThread::current. If called from
997 // the VMThread, it also returns the JavaThread that instigated the VMThread's
998 // operation. You may not want that either.
999 static JavaThread* active();
1000
1001 protected:
1002 virtual void pre_run();
1003 virtual void run();
1004 void thread_main_inner();
1005 virtual void post_run();
1006
1007 public:
1008 // Thread local information maintained by JVMTI.
1009 void set_jvmti_thread_state(JvmtiThreadState *value) { _jvmti_thread_state = value; }
1010 // A JvmtiThreadState is lazily allocated. This jvmti_thread_state()
1011 // getter is used to get this JavaThread's JvmtiThreadState if it has
1012 // one which means null can be returned. JvmtiThreadState::state_for()
1013 // is used to get the specified JavaThread's JvmtiThreadState if it has
1014 // one or it allocates a new JvmtiThreadState for the JavaThread and
1015 // returns it. JvmtiThreadState::state_for() will return null only if
1016 // the specified JavaThread is exiting.
1017 JvmtiThreadState *jvmti_thread_state() const { return _jvmti_thread_state; }
1018 static ByteSize jvmti_thread_state_offset() { return byte_offset_of(JavaThread, _jvmti_thread_state); }
1019
1020 #if INCLUDE_JVMTI
1021 // Rebind JVMTI thread state from carrier to virtual or from virtual to carrier.
1022 JvmtiThreadState *rebind_to_jvmti_thread_state_of(oop thread_oop);
1023 #endif
1024
1025 // JVMTI PopFrame support
1026 // Setting and clearing popframe_condition
1027 // All of these enumerated values are bits. popframe_pending
1028 // indicates that a PopFrame() has been requested and not yet been
1029 // completed. popframe_processing indicates that that PopFrame() is in
1030 // the process of being completed. popframe_force_deopt_reexecution_bit
1031 // indicates that special handling is required when returning to a
1032 // deoptimized caller.
1033 enum PopCondition {
1034 popframe_inactive = 0x00,
1035 popframe_pending_bit = 0x01,
1036 popframe_processing_bit = 0x02,
1037 popframe_force_deopt_reexecution_bit = 0x04
1038 };
1039 PopCondition popframe_condition() { return (PopCondition) _popframe_condition; }
1040 void set_popframe_condition(PopCondition c) { _popframe_condition = c; }
1041 void set_popframe_condition_bit(PopCondition c) { _popframe_condition |= c; }
1042 void clear_popframe_condition() { _popframe_condition = popframe_inactive; }
1043 static ByteSize popframe_condition_offset() { return byte_offset_of(JavaThread, _popframe_condition); }
1044 bool has_pending_popframe() { return (popframe_condition() & popframe_pending_bit) != 0; }
1045 bool popframe_forcing_deopt_reexecution() { return (popframe_condition() & popframe_force_deopt_reexecution_bit) != 0; }
1046
1047 bool pop_frame_in_process(void) { return ((_popframe_condition & popframe_processing_bit) != 0); }
1048 void set_pop_frame_in_process(void) { _popframe_condition |= popframe_processing_bit; }
1049 void clr_pop_frame_in_process(void) { _popframe_condition &= ~popframe_processing_bit; }
1050
1051 int frames_to_pop_failed_realloc() const { return _frames_to_pop_failed_realloc; }
1052 void set_frames_to_pop_failed_realloc(int nb) { _frames_to_pop_failed_realloc = nb; }
1053 void dec_frames_to_pop_failed_realloc() { _frames_to_pop_failed_realloc--; }
1054
1055 private:
1056 // Saved incoming arguments to popped frame.
1057 // Used only when popped interpreted frame returns to deoptimized frame.
1058 void* _popframe_preserved_args;
1059 int _popframe_preserved_args_size;
1060
1061 public:
1062 void popframe_preserve_args(ByteSize size_in_bytes, void* start);
1063 void* popframe_preserved_args();
1064 ByteSize popframe_preserved_args_size();
1065 WordSize popframe_preserved_args_size_in_words();
1066 void popframe_free_preserved_args();
1067
1068
1069 private:
1070 JvmtiThreadState *_jvmti_thread_state;
1071
1072 // Used by the interpreter in fullspeed mode for frame pop, method
1073 // entry, method exit and single stepping support. This field is
1074 // only set to non-zero at a safepoint or using a direct handshake
1075 // (see EnterInterpOnlyModeClosure).
1076 // It can be set to zero asynchronously to this threads execution (i.e., without
1077 // safepoint/handshake or a lock) so we have to be very careful.
1078 // Accesses by other threads are synchronized using JvmtiThreadState_lock though.
1079 int _interp_only_mode;
1080
1081 public:
1082 // used by the interpreter for fullspeed debugging support (see above)
1083 static ByteSize interp_only_mode_offset() { return byte_offset_of(JavaThread, _interp_only_mode); }
1084 bool is_interp_only_mode() { return (_interp_only_mode != 0); }
1085 int get_interp_only_mode() { return _interp_only_mode; }
1086 int set_interp_only_mode(int val) { return _interp_only_mode = val; }
1087 void increment_interp_only_mode() { ++_interp_only_mode; }
1088 void decrement_interp_only_mode() { --_interp_only_mode; }
1089
1090 // support for cached flag that indicates whether exceptions need to be posted for this thread
1091 // if this is false, we can avoid deoptimizing when events are thrown
1092 // this gets set to reflect whether jvmtiExport::post_exception_throw would actually do anything
1093 private:
1094 int _should_post_on_exceptions_flag;
1095
1096 public:
1097 void set_should_post_on_exceptions_flag(int val) { _should_post_on_exceptions_flag = val; }
1098
1099 private:
1100 ThreadStatistics *_thread_stat;
1101
1102 public:
1103 ThreadStatistics* get_thread_stat() const { return _thread_stat; }
1104
1105 // Return a blocker object for which this thread is blocked parking.
1106 oop current_park_blocker();
1107
1108 private:
1109 static size_t _stack_size_at_create;
1110
1111 public:
1112 static inline size_t stack_size_at_create(void) {
1113 return _stack_size_at_create;
1114 }
1115 static inline void set_stack_size_at_create(size_t value) {
1116 _stack_size_at_create = value;
1117 }
1118
1119 // Machine dependent stuff
1120 #include OS_CPU_HEADER(javaThread)
1121
1122 // JSR166 per-thread parker
1123 private:
1124 Parker _parker;
1125 public:
1126 Parker* parker() { return &_parker; }
1127
1128 public:
1129 // clearing/querying jni attach status
1130 bool is_attaching_via_jni() const { return _jni_attach_state == _attaching_via_jni; }
1131 bool has_attached_via_jni() const { return is_attaching_via_jni() || _jni_attach_state == _attached_via_jni; }
1132 inline void set_done_attaching_via_jni();
1133
1134 // Stack dump assistance:
1135 // Track the class we want to initialize but for which we have to wait
1136 // on its init_lock() because it is already being initialized.
1137 void set_class_to_be_initialized(InstanceKlass* k);
1138 InstanceKlass* class_to_be_initialized() const;
1139
1140 private:
1141 InstanceKlass* _class_to_be_initialized;
1142
1143 // java.lang.Thread.sleep support
1144 ParkEvent * _SleepEvent;
1145 public:
1146 bool sleep(jlong millis);
1147 bool sleep_nanos(jlong nanos);
1148
1149 // java.lang.Thread interruption support
1150 void interrupt();
1151 bool is_interrupted(bool clear_interrupted);
1152
1153 // This is only for use by JVMTI RawMonitorWait. It emulates the actions of
1154 // the Java code in Object::wait which are not present in RawMonitorWait.
1155 bool get_and_clear_interrupted();
1156
1157 private:
1158 LockStack _lock_stack;
1159 OMCache _om_cache;
1160
1161 public:
1162 LockStack& lock_stack() { return _lock_stack; }
1163 size_t _unlocked_inflation = 0;
1164 size_t _recursive_inflation = 0;
1165 size_t _contended_recursive_inflation = 0;
1166 size_t _contended_inflation = 0;
1167 size_t _wait_inflation = 0;
1168 size_t _lock_stack_inflation = 0;
1169
1170 size_t _wait_deflation = 0;
1171 size_t _exit_deflation = 0;
1172
1173 size_t _lock_lookup = 0;
1174 size_t _lock_hit = 0;
1175 size_t _unlock_lookup = 0;
1176 size_t _unlock_hit = 0;
1177
1178 static ByteSize lock_lookup_offset() { return byte_offset_of(JavaThread, _lock_lookup); }
1179 static ByteSize lock_hit_offset() { return byte_offset_of(JavaThread, _lock_hit); }
1180 static ByteSize unlock_lookup_offset() { return byte_offset_of(JavaThread, _unlock_lookup); }
1181 static ByteSize unlock_hit_offset() { return byte_offset_of(JavaThread, _unlock_hit); }
1182
1183 static ByteSize lock_stack_offset() { return byte_offset_of(JavaThread, _lock_stack); }
1184 // Those offsets are used in code generators to access the LockStack that is embedded in this
1185 // JavaThread structure. Those accesses are relative to the current thread, which
1186 // is typically in a dedicated register.
1187 static ByteSize lock_stack_top_offset() { return lock_stack_offset() + LockStack::top_offset(); }
1188 static ByteSize lock_stack_base_offset() { return lock_stack_offset() + LockStack::base_offset(); }
1189
1190
1191 static ByteSize om_cache_offset() { return byte_offset_of(JavaThread, _om_cache); }
1192 static ByteSize om_cache_oops_offset() { return om_cache_offset() + OMCache::entries(); }
1193
1194 void om_set_monitor_cache(ObjectMonitor* monitor);
1195 void om_clear_monitor_cache();
1196 ObjectMonitor* om_get_from_monitor_cache(oop obj);
1197
1198 static OopStorage* thread_oop_storage();
1199
1200 static void verify_cross_modify_fence_failure(JavaThread *thread) PRODUCT_RETURN;
1201
1202 // Helper function to create the java.lang.Thread object for a
1203 // VM-internal thread. The thread will have the given name and be
1204 // part of the System ThreadGroup.
1205 static Handle create_system_thread_object(const char* name, TRAPS);
1206
1207 // Helper function to start a VM-internal daemon thread.
1208 // E.g. ServiceThread, NotificationThread, CompilerThread etc.
1209 static void start_internal_daemon(JavaThread* current, JavaThread* target,
1210 Handle thread_oop, ThreadPriority prio);
1211
1212 // Helper function to do vm_exit_on_initialization for osthread
1213 // resource allocation failure.
1214 static void vm_exit_on_osthread_failure(JavaThread* thread);
1215
1216 // Deferred OopHandle release support
1217 private:
1218 // List of OopHandles to be released - guarded by the Service_lock.
1219 static OopHandleList* _oop_handle_list;
1220 // Add our OopHandles to the list for the service thread to release.
1221 void add_oop_handles_for_release();
1222 // Called by the ServiceThread to release the OopHandles.
1223 static void release_oop_handles();
1224 // Called by the ServiceThread to poll if there are any OopHandles to release.
1225 // Called when holding the Service_lock.
1226 static bool has_oop_handles_to_release() {
1227 return _oop_handle_list != nullptr;
1228 }
1229 };
1230
1231 inline JavaThread* JavaThread::current_or_null() {
1232 Thread* current = Thread::current_or_null();
1233 return current != nullptr ? JavaThread::cast(current) : nullptr;
1234 }
1235
1236 class UnlockFlagSaver {
1237 private:
1238 JavaThread* _thread;
1239 bool _do_not_unlock;
1240 public:
1241 UnlockFlagSaver(JavaThread* t) {
1242 _thread = t;
1243 _do_not_unlock = t->do_not_unlock_if_synchronized();
1244 t->set_do_not_unlock_if_synchronized(false);
1245 }
1246 ~UnlockFlagSaver() {
1247 _thread->set_do_not_unlock_if_synchronized(_do_not_unlock);
1248 }
1249 };
1250
1251 class JNIHandleMark : public StackObj {
1252 JavaThread* _thread;
1253 public:
1254 JNIHandleMark(JavaThread* thread) : _thread(thread) {
1255 thread->push_jni_handle_block();
1256 }
1257 ~JNIHandleMark() { _thread->pop_jni_handle_block(); }
1258 };
1259
1260 #endif // SHARE_RUNTIME_JAVATHREAD_HPP