1 /*
2 * Copyright (c) 1997, 2023, 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/park.hpp"
38 #include "runtime/safepointMechanism.hpp"
39 #include "runtime/stackWatermarkSet.hpp"
40 #include "runtime/stackOverflow.hpp"
41 #include "runtime/thread.hpp"
42 #include "runtime/threadHeapSampler.hpp"
43 #include "runtime/threadStatisticalInfo.hpp"
44 #include "utilities/exceptions.hpp"
45 #include "utilities/globalDefinitions.hpp"
46 #include "utilities/macros.hpp"
47 #if INCLUDE_JFR
48 #include "jfr/support/jfrThreadExtension.hpp"
49 #endif
50
51 class AsyncExceptionHandshake;
52 class ContinuationEntry;
53 class DeoptResourceMark;
54 class JNIHandleBlock;
55 class JVMCIRuntime;
56
57 class JvmtiDeferredUpdates;
58 class JvmtiSampledObjectAllocEventCollector;
59 class JvmtiThreadState;
60
61 class Metadata;
62 class OopHandleList;
63 class OopStorage;
64 class OSThread;
65
66 class ThreadsList;
67 class ThreadSafepointState;
68 class ThreadStatistics;
69
70 class vframeArray;
71 class vframe;
72 class javaVFrame;
73
74 class JavaThread;
75 typedef void (*ThreadFunction)(JavaThread*, TRAPS);
76
77 class JavaThread: public Thread {
78 friend class VMStructs;
79 friend class JVMCIVMStructs;
80 friend class WhiteBox;
81 friend class ThreadsSMRSupport; // to access _threadObj for exiting_threads_oops_do
82 friend class HandshakeState;
83 friend class Continuation;
84 friend class Threads;
85 friend class ServiceThread; // for deferred OopHandle release access
86 private:
87 bool _on_thread_list; // Is set when this JavaThread is added to the Threads list
88
89 // All references to Java objects managed via OopHandles. These
90 // have to be released by the ServiceThread after the JavaThread has
91 // terminated - see add_oop_handles_for_release().
92 OopHandle _threadObj; // The Java level thread object
93 OopHandle _vthread; // the value returned by Thread.currentThread(): the virtual thread, if mounted, otherwise _threadObj
94 OopHandle _jvmti_vthread;
95 OopHandle _scopedValueCache;
96
97 static OopStorage* _thread_oop_storage;
98
99 #ifdef ASSERT
100 private:
101 int _java_call_counter;
102
103 public:
104 int java_call_counter() { return _java_call_counter; }
105 void inc_java_call_counter() { _java_call_counter++; }
106 void dec_java_call_counter() {
107 assert(_java_call_counter > 0, "Invalid nesting of JavaCallWrapper");
108 _java_call_counter--;
109 }
110 private: // restore original namespace restriction
111 #endif // ifdef ASSERT
112
113 JavaFrameAnchor _anchor; // Encapsulation of current java frame and it state
114
115 ThreadFunction _entry_point;
116
117 JNIEnv _jni_environment;
118
119 // Deopt support
120 DeoptResourceMark* _deopt_mark; // Holds special ResourceMark for deoptimization
121
122 CompiledMethod* _deopt_nmethod; // CompiledMethod that is currently being deoptimized
123 vframeArray* _vframe_array_head; // Holds the heap of the active vframeArrays
124 vframeArray* _vframe_array_last; // Holds last vFrameArray we popped
125 // Holds updates by JVMTI agents for compiled frames that cannot be performed immediately. They
126 // will be carried out as soon as possible which, in most cases, is just before deoptimization of
127 // the frame, when control returns to it.
128 JvmtiDeferredUpdates* _jvmti_deferred_updates;
129
130 // Handshake value for fixing 6243940. We need a place for the i2c
131 // adapter to store the callee Method*. This value is NEVER live
132 // across a gc point so it does NOT have to be gc'd
133 // The handshake is open ended since we can't be certain that it will
134 // be nulled. This is because we rarely ever see the race and end up
135 // in handle_wrong_method which is the backend of the handshake. See
136 // code in i2c adapters and handle_wrong_method.
137
138 Method* _callee_target;
139
140 // Used to pass back results to the interpreter or generated code running Java code.
141 oop _vm_result; // oop result is GC-preserved
142 Metadata* _vm_result_2; // non-oop result
143 oop _return_buffered_value; // buffered value being returned
144
145 // See ReduceInitialCardMarks: this holds the precise space interval of
146 // the most recent slow path allocation for which compiled code has
147 // elided card-marks for performance along the fast-path.
148 MemRegion _deferred_card_mark;
149
150 ObjectMonitor* volatile _current_pending_monitor; // ObjectMonitor this thread is waiting to lock
151 bool _current_pending_monitor_is_from_java; // locking is from Java code
152 ObjectMonitor* volatile _current_waiting_monitor; // ObjectMonitor on which this thread called Object.wait()
153
154 // Active_handles points to a block of handles
155 JNIHandleBlock* _active_handles;
156
157 // One-element thread local free list
158 JNIHandleBlock* _free_handle_block;
159
160 public:
161 volatile intptr_t _Stalled;
162
163 // For tracking the heavyweight monitor the thread is pending on.
164 ObjectMonitor* current_pending_monitor() {
165 // Use Atomic::load() to prevent data race between concurrent modification and
166 // concurrent readers, e.g. ThreadService::get_current_contended_monitor().
167 // Especially, reloading pointer from thread after null check must be prevented.
168 return Atomic::load(&_current_pending_monitor);
169 }
170 void set_current_pending_monitor(ObjectMonitor* monitor) {
171 Atomic::store(&_current_pending_monitor, monitor);
172 }
173 void set_current_pending_monitor_is_from_java(bool from_java) {
174 _current_pending_monitor_is_from_java = from_java;
175 }
176 bool current_pending_monitor_is_from_java() {
177 return _current_pending_monitor_is_from_java;
178 }
179 ObjectMonitor* current_waiting_monitor() {
180 // See the comment in current_pending_monitor() above.
181 return Atomic::load(&_current_waiting_monitor);
182 }
183 void set_current_waiting_monitor(ObjectMonitor* monitor) {
184 Atomic::store(&_current_waiting_monitor, monitor);
185 }
186
187 // JNI handle support
188 JNIHandleBlock* active_handles() const { return _active_handles; }
189 void set_active_handles(JNIHandleBlock* block) { _active_handles = block; }
190 JNIHandleBlock* free_handle_block() const { return _free_handle_block; }
191 void set_free_handle_block(JNIHandleBlock* block) { _free_handle_block = block; }
192
193 void push_jni_handle_block();
194 void pop_jni_handle_block();
195
196 private:
197 MonitorChunk* _monitor_chunks; // Contains the off stack monitors
198 // allocated during deoptimization
199 // and by JNI_MonitorEnter/Exit
200
201 enum SuspendFlags {
202 // NOTE: avoid using the sign-bit as cc generates different test code
203 // when the sign-bit is used, and sometimes incorrectly - see CR 6398077
204 _trace_flag = 0x00000004U, // call tracing backend
205 _obj_deopt = 0x00000008U // suspend for object reallocation and relocking for JVMTI agent
206 };
207
208 // various suspension related flags - atomically updated
209 volatile uint32_t _suspend_flags;
210
211 inline void set_suspend_flag(SuspendFlags f);
212 inline void clear_suspend_flag(SuspendFlags f);
213
214 public:
215 inline void set_trace_flag();
216 inline void clear_trace_flag();
217 inline void set_obj_deopt_flag();
218 inline void clear_obj_deopt_flag();
219 bool is_trace_suspend() { return (_suspend_flags & _trace_flag) != 0; }
220 bool is_obj_deopt_suspend() { return (_suspend_flags & _obj_deopt) != 0; }
221
222 // Asynchronous exception support
223 private:
224 friend class InstallAsyncExceptionHandshake;
225 friend class AsyncExceptionHandshake;
226 friend class HandshakeState;
227
228 void install_async_exception(AsyncExceptionHandshake* aec = nullptr);
229 void handle_async_exception(oop java_throwable);
230 public:
231 bool has_async_exception_condition();
232 inline void set_pending_unsafe_access_error();
233 static void send_async_exception(JavaThread* jt, oop java_throwable);
234
235 class NoAsyncExceptionDeliveryMark : public StackObj {
236 friend JavaThread;
237 JavaThread *_target;
238 inline NoAsyncExceptionDeliveryMark(JavaThread *t);
239 inline ~NoAsyncExceptionDeliveryMark();
240 };
241
242 // Safepoint support
243 public: // Expose _thread_state for SafeFetchInt()
244 volatile JavaThreadState _thread_state;
245 private:
246 SafepointMechanism::ThreadData _poll_data;
247 ThreadSafepointState* _safepoint_state; // Holds information about a thread during a safepoint
248 address _saved_exception_pc; // Saved pc of instruction where last implicit exception happened
249 NOT_PRODUCT(bool _requires_cross_modify_fence;) // State used by VerifyCrossModifyFence
250 #ifdef ASSERT
251 // Debug support for checking if code allows safepoints or not.
252 // Safepoints in the VM can happen because of allocation, invoking a VM operation, or blocking on
253 // mutex, or blocking on an object synchronizer (Java locking).
254 // If _no_safepoint_count is non-zero, then an assertion failure will happen in any of
255 // the above cases. The class NoSafepointVerifier is used to set this counter.
256 int _no_safepoint_count; // If 0, thread allow a safepoint to happen
257
258 public:
259 void inc_no_safepoint_count() { _no_safepoint_count++; }
260 void dec_no_safepoint_count() { _no_safepoint_count--; }
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 #ifdef ASSERT
321 bool _is_VTMS_transition_disabler; // thread currently disabled VTMS transitions
322 #endif
323 #endif
324
325 // JNI attach states:
326 enum JNIAttachStates {
327 _not_attaching_via_jni = 1, // thread is not attaching via JNI
328 _attaching_via_jni, // thread is attaching via JNI
329 _attached_via_jni // thread has attached via JNI
330 };
331
332 // A regular JavaThread's _jni_attach_state is _not_attaching_via_jni.
333 // A native thread that is attaching via JNI starts with a value
334 // of _attaching_via_jni and transitions to _attached_via_jni.
335 volatile JNIAttachStates _jni_attach_state;
336
337
338 #if INCLUDE_JVMCI
339 // The _pending_* fields below are used to communicate extra information
340 // from an uncommon trap in JVMCI compiled code to the uncommon trap handler.
341
342 // Communicates the DeoptReason and DeoptAction of the uncommon trap
343 int _pending_deoptimization;
344
345 // Specifies whether the uncommon trap is to bci 0 of a synchronized method
346 // before the monitor has been acquired.
347 bool _pending_monitorenter;
348
349 // Specifies if the DeoptReason for the last uncommon trap was Reason_transfer_to_interpreter
350 bool _pending_transfer_to_interpreter;
351
352 // True if in a runtime call from compiled code that will deoptimize
353 // and re-execute a failed heap allocation in the interpreter.
354 bool _in_retryable_allocation;
355
356 // An id of a speculation that JVMCI compiled code can use to further describe and
357 // uniquely identify the speculative optimization guarded by an uncommon trap.
358 // See JVMCINMethodData::SPECULATION_LENGTH_BITS for further details.
359 jlong _pending_failed_speculation;
360
361 // These fields are mutually exclusive in terms of live ranges.
362 union {
363 // Communicates the pc at which the most recent implicit exception occurred
364 // from the signal handler to a deoptimization stub.
365 address _implicit_exception_pc;
366
367 // Communicates an alternative call target to an i2c stub from a JavaCall .
368 address _alternate_call_target;
369 } _jvmci;
370
371 // The JVMCIRuntime in a JVMCI shared library
372 JVMCIRuntime* _libjvmci_runtime;
373
374 // Support for high precision, thread sensitive counters in JVMCI compiled code.
375 jlong* _jvmci_counters;
376
377 // Fast thread locals for use by JVMCI
378 jlong _jvmci_reserved0;
379 jlong _jvmci_reserved1;
380 oop _jvmci_reserved_oop0;
381
382 public:
383 static jlong* _jvmci_old_thread_counters;
384 static void collect_counters(jlong* array, int length);
385
386 bool resize_counters(int current_size, int new_size);
387
388 static bool resize_all_jvmci_counters(int new_size);
389
390 void set_jvmci_reserved_oop0(oop value) {
391 _jvmci_reserved_oop0 = value;
392 }
393
394 oop get_jvmci_reserved_oop0() {
395 return _jvmci_reserved_oop0;
396 }
397
398 void set_jvmci_reserved0(jlong value) {
399 _jvmci_reserved0 = value;
400 }
401
402 jlong get_jvmci_reserved0() {
403 return _jvmci_reserved0;
404 }
405
406 void set_jvmci_reserved1(jlong value) {
407 _jvmci_reserved1 = value;
408 }
409
410 jlong get_jvmci_reserved1() {
411 return _jvmci_reserved1;
412 }
413
414 private:
415 #endif // INCLUDE_JVMCI
416
417 StackOverflow _stack_overflow_state;
418
419 void pretouch_stack();
420
421 // Compiler exception handling (NOTE: The _exception_oop is *NOT* the same as _pending_exception. It is
422 // used to temp. parsing values into and out of the runtime system during exception handling for compiled
423 // code)
424 volatile oop _exception_oop; // Exception thrown in compiled code
425 volatile address _exception_pc; // PC where exception happened
426 volatile address _exception_handler_pc; // PC for handler of exception
427 volatile int _is_method_handle_return; // true (== 1) if the current exception PC is a MethodHandle call site.
428
429 private:
430 // support for JNI critical regions
431 jint _jni_active_critical; // count of entries into JNI critical region
432
433 // Checked JNI: function name requires exception check
434 char* _pending_jni_exception_check_fn;
435
436 // For deadlock detection.
437 int _depth_first_number;
438
439 // JVMTI PopFrame support
440 // This is set to popframe_pending to signal that top Java frame should be popped immediately
441 int _popframe_condition;
442
443 // If reallocation of scalar replaced objects fails, we throw OOM
444 // and during exception propagation, pop the top
445 // _frames_to_pop_failed_realloc frames, the ones that reference
446 // failed reallocations.
447 int _frames_to_pop_failed_realloc;
448
449 ContinuationEntry* _cont_entry;
450 intptr_t* _cont_fastpath; // the sp of the oldest known interpreted/call_stub frame inside the
451 // continuation that we know about
452 int _cont_fastpath_thread_state; // whether global thread state allows continuation fastpath (JVMTI)
453 // It's signed for error detection.
454 #ifdef _LP64
455 int64_t _held_monitor_count; // used by continuations for fast lock detection
456 int64_t _jni_monitor_count;
457 #else
458 int32_t _held_monitor_count; // used by continuations for fast lock detection
459 int32_t _jni_monitor_count;
460 #endif
461
462 private:
463
464 friend class VMThread;
465 friend class ThreadWaitTransition;
466 friend class VM_Exit;
467
468 // Stack watermark barriers.
469 StackWatermarks _stack_watermarks;
470
471 public:
472 inline StackWatermarks* stack_watermarks() { return &_stack_watermarks; }
473
474 public:
475 // Constructor
476 JavaThread(); // delegating constructor
477 JavaThread(bool is_attaching_via_jni); // for main thread and JNI attached threads
478 JavaThread(ThreadFunction entry_point, size_t stack_size = 0);
479 ~JavaThread();
480
481 #ifdef ASSERT
482 // verify this JavaThread hasn't be published in the Threads::list yet
483 void verify_not_published();
484 #endif // ASSERT
485
486 StackOverflow* stack_overflow_state() { return &_stack_overflow_state; }
487
488 //JNI functiontable getter/setter for JVMTI jni function table interception API.
489 void set_jni_functions(struct JNINativeInterface_* functionTable) {
490 _jni_environment.functions = functionTable;
491 }
492 struct JNINativeInterface_* get_jni_functions() {
493 return (struct JNINativeInterface_ *)_jni_environment.functions;
494 }
495
496 // This function is called at thread creation to allow
497 // platform specific thread variables to be initialized.
498 void cache_global_variables();
499
500 // Executes Shutdown.shutdown()
501 void invoke_shutdown_hooks();
502
503 // Cleanup on thread exit
504 enum ExitType {
505 normal_exit,
506 jni_detach
507 };
508 void exit(bool destroy_vm, ExitType exit_type = normal_exit);
509
510 void cleanup_failed_attach_current_thread(bool is_daemon);
511
512 // Testers
513 virtual bool is_Java_thread() const { return true; }
514 virtual bool can_call_java() const { return true; }
515
516 virtual bool is_active_Java_thread() const {
517 return on_thread_list() && !is_terminated();
518 }
519
520 // Thread oop. threadObj() can be null for initial JavaThread
521 // (or for threads attached via JNI)
522 oop threadObj() const;
523 void set_threadOopHandles(oop p);
524 oop vthread() const;
525 void set_vthread(oop p);
526 oop scopedValueCache() const;
527 void set_scopedValueCache(oop p);
528 void clear_scopedValueBindings();
529 oop jvmti_vthread() const;
530 void set_jvmti_vthread(oop p);
531
532 // Prepare thread and add to priority queue. If a priority is
533 // not specified, use the priority of the thread object. Threads_lock
534 // must be held while this function is called.
535 void prepare(jobject jni_thread, ThreadPriority prio=NoPriority);
536
537 void set_saved_exception_pc(address pc) { _saved_exception_pc = pc; }
538 address saved_exception_pc() { return _saved_exception_pc; }
539
540 ThreadFunction entry_point() const { return _entry_point; }
541
542 // Allocates a new Java level thread object for this thread. thread_name may be null.
543 void allocate_threadObj(Handle thread_group, const char* thread_name, bool daemon, TRAPS);
544
545 // Last frame anchor routines
546
547 JavaFrameAnchor* frame_anchor(void) { return &_anchor; }
548
549 // last_Java_sp
550 bool has_last_Java_frame() const { return _anchor.has_last_Java_frame(); }
551 intptr_t* last_Java_sp() const { return _anchor.last_Java_sp(); }
552
553 // last_Java_pc
554
555 address last_Java_pc(void) { return _anchor.last_Java_pc(); }
556
557 // Safepoint support
558 inline JavaThreadState thread_state() const;
559 inline void set_thread_state(JavaThreadState s);
560 inline void set_thread_state_fence(JavaThreadState s); // fence after setting thread state
561 inline ThreadSafepointState* safepoint_state() const;
562 inline void set_safepoint_state(ThreadSafepointState* state);
563 inline bool is_at_poll_safepoint();
564
565 // JavaThread termination and lifecycle support:
566 void smr_delete();
567 bool on_thread_list() const { return _on_thread_list; }
568 void set_on_thread_list() { _on_thread_list = true; }
569
570 // thread has called JavaThread::exit(), thread's GC barrier is detached
571 // or thread is terminated
572 bool is_exiting() const;
573 // thread's GC barrier is NOT detached and thread is NOT terminated
574 bool is_oop_safe() const;
575 // thread is terminated (no longer on the threads list); the thread must
576 // be protected by a ThreadsListHandle to avoid potential crashes.
577 bool check_is_terminated(TerminatedTypes l_terminated) const {
578 return l_terminated == _thread_terminated || l_terminated == _vm_exited;
579 }
580 bool is_terminated() const;
581 void set_terminated(TerminatedTypes t);
582
583 void block_if_vm_exited();
584
585 bool doing_unsafe_access() { return _doing_unsafe_access; }
586 void set_doing_unsafe_access(bool val) { _doing_unsafe_access = val; }
587
588 bool do_not_unlock_if_synchronized() { return _do_not_unlock_if_synchronized; }
589 void set_do_not_unlock_if_synchronized(bool val) { _do_not_unlock_if_synchronized = val; }
590
591 SafepointMechanism::ThreadData* poll_data() { return &_poll_data; }
592
593 void set_requires_cross_modify_fence(bool val) PRODUCT_RETURN NOT_PRODUCT({ _requires_cross_modify_fence = val; })
594
595 // Continuation support
596 ContinuationEntry* last_continuation() const { return _cont_entry; }
597 void set_cont_fastpath(intptr_t* x) { _cont_fastpath = x; }
598 void push_cont_fastpath(intptr_t* sp) { if (sp > _cont_fastpath) _cont_fastpath = sp; }
599 void set_cont_fastpath_thread_state(bool x) { _cont_fastpath_thread_state = (int)x; }
600 intptr_t* raw_cont_fastpath() const { return _cont_fastpath; }
601 bool cont_fastpath() const { return _cont_fastpath == nullptr && _cont_fastpath_thread_state != 0; }
602 bool cont_fastpath_thread_state() const { return _cont_fastpath_thread_state != 0; }
603
604 void inc_held_monitor_count(int i = 1, bool jni = false);
605 void dec_held_monitor_count(int i = 1, bool jni = false);
606
607 int64_t held_monitor_count() { return (int64_t)_held_monitor_count; }
608 int64_t jni_monitor_count() { return (int64_t)_jni_monitor_count; }
609 void clear_jni_monitor_count() { _jni_monitor_count = 0; }
610
611 inline bool is_vthread_mounted() const;
612 inline const ContinuationEntry* vthread_continuation() const;
613
614 private:
615 DEBUG_ONLY(void verify_frame_info();)
616
617 // Support for thread handshake operations
618 HandshakeState _handshake;
619 public:
620 HandshakeState* handshake_state() { return &_handshake; }
621
622 // A JavaThread can always safely operate on it self and other threads
623 // can do it safely if they are the active handshaker.
624 bool is_handshake_safe_for(Thread* th) const {
625 return _handshake.active_handshaker() == th || this == th;
626 }
627
628 // Suspend/resume support for JavaThread
629 // higher-level suspension/resume logic called by the public APIs
630 bool java_suspend();
631 bool java_resume();
632 bool is_suspended() { return _handshake.is_suspended(); }
633
634 // Check for async exception in addition to safepoint.
635 static void check_special_condition_for_native_trans(JavaThread *thread);
636
637 // Synchronize with another thread that is deoptimizing objects of the
638 // current thread, i.e. reverts optimizations based on escape analysis.
639 void wait_for_object_deoptimization();
640
641 #if INCLUDE_JVMTI
642 inline void set_carrier_thread_suspended();
643 inline void clear_carrier_thread_suspended();
644
645 bool is_carrier_thread_suspended() const {
646 return _carrier_thread_suspended;
647 }
648
649 bool is_in_VTMS_transition() const { return _is_in_VTMS_transition; }
650 bool is_in_tmp_VTMS_transition() const { return _is_in_tmp_VTMS_transition; }
651 bool is_in_any_VTMS_transition() const { return _is_in_VTMS_transition || _is_in_tmp_VTMS_transition; }
652
653 void set_is_in_VTMS_transition(bool val);
654 void toggle_is_in_tmp_VTMS_transition() { _is_in_tmp_VTMS_transition = !_is_in_tmp_VTMS_transition; };
655
656 #ifdef ASSERT
657 bool is_VTMS_transition_disabler() const { return _is_VTMS_transition_disabler; }
658 void set_is_VTMS_transition_disabler(bool val);
659 #endif
660 #endif
661
662 // Support for object deoptimization and JFR suspension
663 void handle_special_runtime_exit_condition();
664 bool has_special_runtime_exit_condition() {
665 return (_suspend_flags & (_obj_deopt JFR_ONLY(| _trace_flag))) != 0;
666 }
667
668 // Fast-locking support
669 bool is_lock_owned(address adr) const;
670
671 // Accessors for vframe array top
672 // The linked list of vframe arrays are sorted on sp. This means when we
673 // unpack the head must contain the vframe array to unpack.
674 void set_vframe_array_head(vframeArray* value) { _vframe_array_head = value; }
675 vframeArray* vframe_array_head() const { return _vframe_array_head; }
676
677 // Side structure for deferring update of java frame locals until deopt occurs
678 JvmtiDeferredUpdates* deferred_updates() const { return _jvmti_deferred_updates; }
679 void set_deferred_updates(JvmtiDeferredUpdates* du) { _jvmti_deferred_updates = du; }
680
681 // These only really exist to make debugging deopt problems simpler
682
683 void set_vframe_array_last(vframeArray* value) { _vframe_array_last = value; }
684 vframeArray* vframe_array_last() const { return _vframe_array_last; }
685
686 // The special resourceMark used during deoptimization
687
688 void set_deopt_mark(DeoptResourceMark* value) { _deopt_mark = value; }
689 DeoptResourceMark* deopt_mark(void) { return _deopt_mark; }
690
691 void set_deopt_compiled_method(CompiledMethod* nm) { _deopt_nmethod = nm; }
692 CompiledMethod* deopt_compiled_method() { return _deopt_nmethod; }
693
694 Method* callee_target() const { return _callee_target; }
695 void set_callee_target (Method* x) { _callee_target = x; }
696
697 // Oop results of vm runtime calls
698 oop vm_result() const { return _vm_result; }
699 void set_vm_result (oop x) { _vm_result = x; }
700
701 void set_vm_result_2 (Metadata* x) { _vm_result_2 = x; }
702
703 oop return_buffered_value() const { return _return_buffered_value; }
704 void set_return_buffered_value(oop val) { _return_buffered_value = val; }
705
706 MemRegion deferred_card_mark() const { return _deferred_card_mark; }
707 void set_deferred_card_mark(MemRegion mr) { _deferred_card_mark = mr; }
708
709 #if INCLUDE_JVMCI
710 jlong pending_failed_speculation() const { return _pending_failed_speculation; }
711 void set_pending_monitorenter(bool b) { _pending_monitorenter = b; }
712 void set_pending_deoptimization(int reason) { _pending_deoptimization = reason; }
713 void set_pending_failed_speculation(jlong failed_speculation) { _pending_failed_speculation = failed_speculation; }
714 void set_pending_transfer_to_interpreter(bool b) { _pending_transfer_to_interpreter = b; }
715 void set_jvmci_alternate_call_target(address a) { assert(_jvmci._alternate_call_target == nullptr, "must be"); _jvmci._alternate_call_target = a; }
716 void set_jvmci_implicit_exception_pc(address a) { assert(_jvmci._implicit_exception_pc == nullptr, "must be"); _jvmci._implicit_exception_pc = a; }
717
718 virtual bool in_retryable_allocation() const { return _in_retryable_allocation; }
719 void set_in_retryable_allocation(bool b) { _in_retryable_allocation = b; }
720
721 JVMCIRuntime* libjvmci_runtime() const { return _libjvmci_runtime; }
722 void set_libjvmci_runtime(JVMCIRuntime* rt) {
723 assert((_libjvmci_runtime == nullptr && rt != nullptr) || (_libjvmci_runtime != nullptr && rt == nullptr), "must be");
724 _libjvmci_runtime = rt;
725 }
726 #endif // INCLUDE_JVMCI
727
728 // Exception handling for compiled methods
729 oop exception_oop() const;
730 address exception_pc() const { return _exception_pc; }
731
732 void set_exception_oop(oop o);
733 void set_exception_pc(address a) { _exception_pc = a; }
734 void set_exception_handler_pc(address a) { _exception_handler_pc = a; }
735 void set_is_method_handle_return(bool value) { _is_method_handle_return = value ? 1 : 0; }
736
737 void clear_exception_oop_and_pc() {
738 set_exception_oop(nullptr);
739 set_exception_pc(nullptr);
740 }
741
742 // Check if address is in the usable part of the stack (excludes protected
743 // guard pages). Can be applied to any thread and is an approximation for
744 // using is_in_live_stack when the query has to happen from another thread.
745 bool is_in_usable_stack(address adr) const {
746 return is_in_stack_range_incl(adr, _stack_overflow_state.stack_reserved_zone_base());
747 }
748
749 // Misc. accessors/mutators
750 static ByteSize scopedValueCache_offset() { return byte_offset_of(JavaThread, _scopedValueCache); }
751
752 // For assembly stub generation
753 static ByteSize threadObj_offset() { return byte_offset_of(JavaThread, _threadObj); }
754 static ByteSize vthread_offset() { return byte_offset_of(JavaThread, _vthread); }
755 static ByteSize jni_environment_offset() { return byte_offset_of(JavaThread, _jni_environment); }
756 static ByteSize pending_jni_exception_check_fn_offset() {
757 return byte_offset_of(JavaThread, _pending_jni_exception_check_fn);
758 }
759 static ByteSize last_Java_sp_offset() {
760 return byte_offset_of(JavaThread, _anchor) + JavaFrameAnchor::last_Java_sp_offset();
761 }
762 static ByteSize last_Java_pc_offset() {
763 return byte_offset_of(JavaThread, _anchor) + JavaFrameAnchor::last_Java_pc_offset();
764 }
765 static ByteSize frame_anchor_offset() {
766 return byte_offset_of(JavaThread, _anchor);
767 }
768 static ByteSize callee_target_offset() { return byte_offset_of(JavaThread, _callee_target); }
769 static ByteSize vm_result_offset() { return byte_offset_of(JavaThread, _vm_result); }
770 static ByteSize vm_result_2_offset() { return byte_offset_of(JavaThread, _vm_result_2); }
771 static ByteSize return_buffered_value_offset() { return byte_offset_of(JavaThread, _return_buffered_value); }
772 static ByteSize thread_state_offset() { return byte_offset_of(JavaThread, _thread_state); }
773 static ByteSize polling_word_offset() { return byte_offset_of(JavaThread, _poll_data) + byte_offset_of(SafepointMechanism::ThreadData, _polling_word);}
774 static ByteSize polling_page_offset() { return byte_offset_of(JavaThread, _poll_data) + byte_offset_of(SafepointMechanism::ThreadData, _polling_page);}
775 static ByteSize saved_exception_pc_offset() { return byte_offset_of(JavaThread, _saved_exception_pc); }
776 static ByteSize osthread_offset() { return byte_offset_of(JavaThread, _osthread); }
777 #if INCLUDE_JVMCI
778 static ByteSize pending_deoptimization_offset() { return byte_offset_of(JavaThread, _pending_deoptimization); }
779 static ByteSize pending_monitorenter_offset() { return byte_offset_of(JavaThread, _pending_monitorenter); }
780 static ByteSize jvmci_alternate_call_target_offset() { return byte_offset_of(JavaThread, _jvmci._alternate_call_target); }
781 static ByteSize jvmci_implicit_exception_pc_offset() { return byte_offset_of(JavaThread, _jvmci._implicit_exception_pc); }
782 static ByteSize jvmci_counters_offset() { return byte_offset_of(JavaThread, _jvmci_counters); }
783 #endif // INCLUDE_JVMCI
784 static ByteSize exception_oop_offset() { return byte_offset_of(JavaThread, _exception_oop); }
785 static ByteSize exception_pc_offset() { return byte_offset_of(JavaThread, _exception_pc); }
786 static ByteSize exception_handler_pc_offset() { return byte_offset_of(JavaThread, _exception_handler_pc); }
787 static ByteSize is_method_handle_return_offset() { return byte_offset_of(JavaThread, _is_method_handle_return); }
788
789 static ByteSize active_handles_offset() { return byte_offset_of(JavaThread, _active_handles); }
790
791 // StackOverflow offsets
792 static ByteSize stack_overflow_limit_offset() {
793 return byte_offset_of(JavaThread, _stack_overflow_state._stack_overflow_limit);
794 }
795 static ByteSize stack_guard_state_offset() {
796 return byte_offset_of(JavaThread, _stack_overflow_state._stack_guard_state);
797 }
798 static ByteSize reserved_stack_activation_offset() {
799 return byte_offset_of(JavaThread, _stack_overflow_state._reserved_stack_activation);
800 }
801 static ByteSize shadow_zone_safe_limit() {
802 return byte_offset_of(JavaThread, _stack_overflow_state._shadow_zone_safe_limit);
803 }
804 static ByteSize shadow_zone_growth_watermark() {
805 return byte_offset_of(JavaThread, _stack_overflow_state._shadow_zone_growth_watermark);
806 }
807
808 static ByteSize suspend_flags_offset() { return byte_offset_of(JavaThread, _suspend_flags); }
809
810 static ByteSize do_not_unlock_if_synchronized_offset() { return byte_offset_of(JavaThread, _do_not_unlock_if_synchronized); }
811 static ByteSize should_post_on_exceptions_flag_offset() {
812 return byte_offset_of(JavaThread, _should_post_on_exceptions_flag);
813 }
814 static ByteSize doing_unsafe_access_offset() { return byte_offset_of(JavaThread, _doing_unsafe_access); }
815 NOT_PRODUCT(static ByteSize requires_cross_modify_fence_offset() { return byte_offset_of(JavaThread, _requires_cross_modify_fence); })
816
817 static ByteSize cont_entry_offset() { return byte_offset_of(JavaThread, _cont_entry); }
818 static ByteSize cont_fastpath_offset() { return byte_offset_of(JavaThread, _cont_fastpath); }
819 static ByteSize held_monitor_count_offset() { return byte_offset_of(JavaThread, _held_monitor_count); }
820
821 #if INCLUDE_JVMTI
822 static ByteSize is_in_VTMS_transition_offset() { return byte_offset_of(JavaThread, _is_in_VTMS_transition); }
823 static ByteSize is_in_tmp_VTMS_transition_offset() { return byte_offset_of(JavaThread, _is_in_tmp_VTMS_transition); }
824 #endif
825
826 // Returns the jni environment for this thread
827 JNIEnv* jni_environment() { return &_jni_environment; }
828
829 // Returns the current thread as indicated by the given JNIEnv.
830 // We don't assert it is Thread::current here as that is done at the
831 // external JNI entry points where the JNIEnv is passed into the VM.
832 static JavaThread* thread_from_jni_environment(JNIEnv* env) {
833 JavaThread* current = reinterpret_cast<JavaThread*>(((intptr_t)env - in_bytes(jni_environment_offset())));
834 // We can't normally get here in a thread that has completed its
835 // execution and so "is_terminated", except when the call is from
836 // AsyncGetCallTrace, which can be triggered by a signal at any point in
837 // a thread's lifecycle. A thread is also considered terminated if the VM
838 // has exited, so we have to check this and block in case this is a daemon
839 // thread returning to the VM (the JNI DirectBuffer entry points rely on
840 // this).
841 if (current->is_terminated()) {
842 current->block_if_vm_exited();
843 }
844 return current;
845 }
846
847 // JNI critical regions. These can nest.
848 bool in_critical() { return _jni_active_critical > 0; }
849 bool in_last_critical() { return _jni_active_critical == 1; }
850 inline void enter_critical();
851 void exit_critical() {
852 assert(Thread::current() == this, "this must be current thread");
853 _jni_active_critical--;
854 assert(_jni_active_critical >= 0, "JNI critical nesting problem?");
855 }
856
857 // Checked JNI: is the programmer required to check for exceptions, if so specify
858 // which function name. Returning to a Java frame should implicitly clear the
859 // pending check, this is done for Native->Java transitions (i.e. user JNI code).
860 // VM->Java transitions are not cleared, it is expected that JNI code enclosed
861 // within ThreadToNativeFromVM makes proper exception checks (i.e. VM internal).
862 bool is_pending_jni_exception_check() const { return _pending_jni_exception_check_fn != nullptr; }
863 void clear_pending_jni_exception_check() { _pending_jni_exception_check_fn = nullptr; }
864 const char* get_pending_jni_exception_check() const { return _pending_jni_exception_check_fn; }
865 void set_pending_jni_exception_check(const char* fn_name) { _pending_jni_exception_check_fn = (char*) fn_name; }
866
867 // For deadlock detection
868 int depth_first_number() { return _depth_first_number; }
869 void set_depth_first_number(int dfn) { _depth_first_number = dfn; }
870
871 private:
872 void set_monitor_chunks(MonitorChunk* monitor_chunks) { _monitor_chunks = monitor_chunks; }
873
874 public:
875 MonitorChunk* monitor_chunks() const { return _monitor_chunks; }
876 void add_monitor_chunk(MonitorChunk* chunk);
877 void remove_monitor_chunk(MonitorChunk* chunk);
878 bool in_deopt_handler() const { return _in_deopt_handler > 0; }
879 void inc_in_deopt_handler() { _in_deopt_handler++; }
880 void dec_in_deopt_handler() {
881 assert(_in_deopt_handler > 0, "mismatched deopt nesting");
882 if (_in_deopt_handler > 0) { // robustness
883 _in_deopt_handler--;
884 }
885 }
886
887 private:
888 void set_entry_point(ThreadFunction entry_point) { _entry_point = entry_point; }
889
890 // factor out low-level mechanics for use in both normal and error cases
891 const char* get_thread_name_string(char* buf = nullptr, int buflen = 0) const;
892
893 public:
894
895 // Frame iteration; calls the function f for all frames on the stack
896 void frames_do(void f(frame*, const RegisterMap*));
897
898 // Memory operations
899 void oops_do_frames(OopClosure* f, CodeBlobClosure* cf);
900 void oops_do_no_frames(OopClosure* f, CodeBlobClosure* cf);
901
902 // GC operations
903 virtual void nmethods_do(CodeBlobClosure* cf);
904
905 // RedefineClasses Support
906 void metadata_do(MetadataClosure* f);
907
908 // Debug method asserting thread states are correct during a handshake operation.
909 DEBUG_ONLY(void verify_states_for_handshake();)
910
911 // Misc. operations
912 const char* name() const;
913 const char* type_name() const { return "JavaThread"; }
914 static const char* name_for(oop thread_obj);
915
916 void print_on(outputStream* st, bool print_extended_info) const;
917 void print_on(outputStream* st) const { print_on(st, false); }
918 void print() const;
919 void print_thread_state_on(outputStream*) const;
920 void print_on_error(outputStream* st, char* buf, int buflen) const;
921 void print_name_on_error(outputStream* st, char* buf, int buflen) const;
922 void verify();
923
924 // Accessing frames
925 frame last_frame() {
926 _anchor.make_walkable();
927 return pd_last_frame();
928 }
929 javaVFrame* last_java_vframe(RegisterMap* reg_map) { return last_java_vframe(last_frame(), reg_map); }
930
931 frame carrier_last_frame(RegisterMap* reg_map);
932 javaVFrame* carrier_last_java_vframe(RegisterMap* reg_map) { return last_java_vframe(carrier_last_frame(reg_map), reg_map); }
933
934 frame vthread_last_frame();
935 javaVFrame* vthread_last_java_vframe(RegisterMap* reg_map) { return last_java_vframe(vthread_last_frame(), reg_map); }
936
937 frame platform_thread_last_frame(RegisterMap* reg_map);
938 javaVFrame* platform_thread_last_java_vframe(RegisterMap* reg_map) {
939 return last_java_vframe(platform_thread_last_frame(reg_map), reg_map);
940 }
941
942 javaVFrame* last_java_vframe(const frame f, RegisterMap* reg_map);
943
944 // Returns method at 'depth' java or native frames down the stack
945 // Used for security checks
946 Klass* security_get_caller_class(int depth);
947
948 // Print stack trace in external format
949 // These variants print carrier/platform thread information only.
950 void print_stack_on(outputStream* st);
951 void print_stack() { print_stack_on(tty); }
952 // This prints the currently mounted virtual thread.
953 void print_vthread_stack_on(outputStream* st);
954 // This prints the active stack: either carrier/platform or virtual.
955 void print_active_stack_on(outputStream* st);
956 // Print current stack trace for checked JNI warnings and JNI fatal errors.
957 // This is the external format from above, but selecting the platform
958 // or vthread as applicable.
959 void print_jni_stack();
960
961 // Print stack traces in various internal formats
962 void trace_stack() PRODUCT_RETURN;
963 void trace_stack_from(vframe* start_vf) PRODUCT_RETURN;
964 void trace_frames() PRODUCT_RETURN;
965
966 // Print an annotated view of the stack frames
967 void print_frame_layout(int depth = 0, bool validate_only = false) NOT_DEBUG_RETURN;
968 void validate_frame_layout() {
969 print_frame_layout(0, true);
970 }
971
972 // Function for testing deoptimization
973 void deoptimize();
974 void make_zombies();
975
976 void deoptimize_marked_methods();
977
978 public:
979 // Returns the running thread as a JavaThread
980 static JavaThread* current() {
981 return JavaThread::cast(Thread::current());
982 }
983
984 // Returns the current thread as a JavaThread, or nullptr if not attached
985 static inline JavaThread* current_or_null();
986
987 // Casts
988 static JavaThread* cast(Thread* t) {
989 assert(t->is_Java_thread(), "incorrect cast to JavaThread");
990 return static_cast<JavaThread*>(t);
991 }
992
993 static const JavaThread* cast(const Thread* t) {
994 assert(t->is_Java_thread(), "incorrect cast to const JavaThread");
995 return static_cast<const JavaThread*>(t);
996 }
997
998 // Returns the active Java thread. Do not use this if you know you are calling
999 // from a JavaThread, as it's slower than JavaThread::current. If called from
1000 // the VMThread, it also returns the JavaThread that instigated the VMThread's
1001 // operation. You may not want that either.
1002 static JavaThread* active();
1003
1004 protected:
1005 virtual void pre_run();
1006 virtual void run();
1007 void thread_main_inner();
1008 virtual void post_run();
1009
1010 public:
1011 // Thread local information maintained by JVMTI.
1012 void set_jvmti_thread_state(JvmtiThreadState *value) { _jvmti_thread_state = value; }
1013 // A JvmtiThreadState is lazily allocated. This jvmti_thread_state()
1014 // getter is used to get this JavaThread's JvmtiThreadState if it has
1015 // one which means null can be returned. JvmtiThreadState::state_for()
1016 // is used to get the specified JavaThread's JvmtiThreadState if it has
1017 // one or it allocates a new JvmtiThreadState for the JavaThread and
1018 // returns it. JvmtiThreadState::state_for() will return null only if
1019 // the specified JavaThread is exiting.
1020 JvmtiThreadState *jvmti_thread_state() const { return _jvmti_thread_state; }
1021 static ByteSize jvmti_thread_state_offset() { return byte_offset_of(JavaThread, _jvmti_thread_state); }
1022
1023 #if INCLUDE_JVMTI
1024 // Rebind JVMTI thread state from carrier to virtual or from virtual to carrier.
1025 JvmtiThreadState *rebind_to_jvmti_thread_state_of(oop thread_oop);
1026 #endif
1027
1028 // JVMTI PopFrame support
1029 // Setting and clearing popframe_condition
1030 // All of these enumerated values are bits. popframe_pending
1031 // indicates that a PopFrame() has been requested and not yet been
1032 // completed. popframe_processing indicates that that PopFrame() is in
1033 // the process of being completed. popframe_force_deopt_reexecution_bit
1034 // indicates that special handling is required when returning to a
1035 // deoptimized caller.
1036 enum PopCondition {
1037 popframe_inactive = 0x00,
1038 popframe_pending_bit = 0x01,
1039 popframe_processing_bit = 0x02,
1040 popframe_force_deopt_reexecution_bit = 0x04
1041 };
1042 PopCondition popframe_condition() { return (PopCondition) _popframe_condition; }
1043 void set_popframe_condition(PopCondition c) { _popframe_condition = c; }
1044 void set_popframe_condition_bit(PopCondition c) { _popframe_condition |= c; }
1045 void clear_popframe_condition() { _popframe_condition = popframe_inactive; }
1046 static ByteSize popframe_condition_offset() { return byte_offset_of(JavaThread, _popframe_condition); }
1047 bool has_pending_popframe() { return (popframe_condition() & popframe_pending_bit) != 0; }
1048 bool popframe_forcing_deopt_reexecution() { return (popframe_condition() & popframe_force_deopt_reexecution_bit) != 0; }
1049
1050 bool pop_frame_in_process(void) { return ((_popframe_condition & popframe_processing_bit) != 0); }
1051 void set_pop_frame_in_process(void) { _popframe_condition |= popframe_processing_bit; }
1052 void clr_pop_frame_in_process(void) { _popframe_condition &= ~popframe_processing_bit; }
1053
1054 int frames_to_pop_failed_realloc() const { return _frames_to_pop_failed_realloc; }
1055 void set_frames_to_pop_failed_realloc(int nb) { _frames_to_pop_failed_realloc = nb; }
1056 void dec_frames_to_pop_failed_realloc() { _frames_to_pop_failed_realloc--; }
1057
1058 private:
1059 // Saved incoming arguments to popped frame.
1060 // Used only when popped interpreted frame returns to deoptimized frame.
1061 void* _popframe_preserved_args;
1062 int _popframe_preserved_args_size;
1063
1064 public:
1065 void popframe_preserve_args(ByteSize size_in_bytes, void* start);
1066 void* popframe_preserved_args();
1067 ByteSize popframe_preserved_args_size();
1068 WordSize popframe_preserved_args_size_in_words();
1069 void popframe_free_preserved_args();
1070
1071
1072 private:
1073 JvmtiThreadState *_jvmti_thread_state;
1074
1075 // Used by the interpreter in fullspeed mode for frame pop, method
1076 // entry, method exit and single stepping support. This field is
1077 // only set to non-zero at a safepoint or using a direct handshake
1078 // (see EnterInterpOnlyModeClosure).
1079 // It can be set to zero asynchronously to this threads execution (i.e., without
1080 // safepoint/handshake or a lock) so we have to be very careful.
1081 // Accesses by other threads are synchronized using JvmtiThreadState_lock though.
1082 int _interp_only_mode;
1083
1084 public:
1085 // used by the interpreter for fullspeed debugging support (see above)
1086 static ByteSize interp_only_mode_offset() { return byte_offset_of(JavaThread, _interp_only_mode); }
1087 bool is_interp_only_mode() { return (_interp_only_mode != 0); }
1088 int get_interp_only_mode() { return _interp_only_mode; }
1089 int set_interp_only_mode(int val) { return _interp_only_mode = val; }
1090 void increment_interp_only_mode() { ++_interp_only_mode; }
1091 void decrement_interp_only_mode() { --_interp_only_mode; }
1092
1093 // support for cached flag that indicates whether exceptions need to be posted for this thread
1094 // if this is false, we can avoid deoptimizing when events are thrown
1095 // this gets set to reflect whether jvmtiExport::post_exception_throw would actually do anything
1096 private:
1097 int _should_post_on_exceptions_flag;
1098
1099 public:
1100 void set_should_post_on_exceptions_flag(int val) { _should_post_on_exceptions_flag = val; }
1101
1102 private:
1103 ThreadStatistics *_thread_stat;
1104
1105 public:
1106 ThreadStatistics* get_thread_stat() const { return _thread_stat; }
1107
1108 // Return a blocker object for which this thread is blocked parking.
1109 oop current_park_blocker();
1110
1111 private:
1112 static size_t _stack_size_at_create;
1113
1114 public:
1115 static inline size_t stack_size_at_create(void) {
1116 return _stack_size_at_create;
1117 }
1118 static inline void set_stack_size_at_create(size_t value) {
1119 _stack_size_at_create = value;
1120 }
1121
1122 // Machine dependent stuff
1123 #include OS_CPU_HEADER(javaThread)
1124
1125 // JSR166 per-thread parker
1126 private:
1127 Parker _parker;
1128 public:
1129 Parker* parker() { return &_parker; }
1130
1131 public:
1132 // clearing/querying jni attach status
1133 bool is_attaching_via_jni() const { return _jni_attach_state == _attaching_via_jni; }
1134 bool has_attached_via_jni() const { return is_attaching_via_jni() || _jni_attach_state == _attached_via_jni; }
1135 inline void set_done_attaching_via_jni();
1136
1137 // Stack dump assistance:
1138 // Track the class we want to initialize but for which we have to wait
1139 // on its init_lock() because it is already being initialized.
1140 void set_class_to_be_initialized(InstanceKlass* k);
1141 InstanceKlass* class_to_be_initialized() const;
1142
1143 private:
1144 InstanceKlass* _class_to_be_initialized;
1145
1146 // java.lang.Thread.sleep support
1147 ParkEvent * _SleepEvent;
1148 public:
1149 bool sleep(jlong millis);
1150
1151 // java.lang.Thread interruption support
1152 void interrupt();
1153 bool is_interrupted(bool clear_interrupted);
1154
1155 static OopStorage* thread_oop_storage();
1156
1157 static void verify_cross_modify_fence_failure(JavaThread *thread) PRODUCT_RETURN;
1158
1159 // Helper function to create the java.lang.Thread object for a
1160 // VM-internal thread. The thread will have the given name and be
1161 // part of the System ThreadGroup.
1162 static Handle create_system_thread_object(const char* name, TRAPS);
1163
1164 // Helper function to start a VM-internal daemon thread.
1165 // E.g. ServiceThread, NotificationThread, CompilerThread etc.
1166 static void start_internal_daemon(JavaThread* current, JavaThread* target,
1167 Handle thread_oop, ThreadPriority prio);
1168
1169 // Helper function to do vm_exit_on_initialization for osthread
1170 // resource allocation failure.
1171 static void vm_exit_on_osthread_failure(JavaThread* thread);
1172
1173 // Deferred OopHandle release support
1174 private:
1175 // List of OopHandles to be released - guarded by the Service_lock.
1176 static OopHandleList* _oop_handle_list;
1177 // Add our OopHandles to the list for the service thread to release.
1178 void add_oop_handles_for_release();
1179 // Called by the ServiceThread to release the OopHandles.
1180 static void release_oop_handles();
1181 // Called by the ServiceThread to poll if there are any OopHandles to release.
1182 // Called when holding the Service_lock.
1183 static bool has_oop_handles_to_release() {
1184 return _oop_handle_list != nullptr;
1185 }
1186 };
1187
1188 inline JavaThread* JavaThread::current_or_null() {
1189 Thread* current = Thread::current_or_null();
1190 return current != nullptr ? JavaThread::cast(current) : nullptr;
1191 }
1192
1193 class UnlockFlagSaver {
1194 private:
1195 JavaThread* _thread;
1196 bool _do_not_unlock;
1197 public:
1198 UnlockFlagSaver(JavaThread* t) {
1199 _thread = t;
1200 _do_not_unlock = t->do_not_unlock_if_synchronized();
1201 t->set_do_not_unlock_if_synchronized(false);
1202 }
1203 ~UnlockFlagSaver() {
1204 _thread->set_do_not_unlock_if_synchronized(_do_not_unlock);
1205 }
1206 };
1207
1208 class JNIHandleMark : public StackObj {
1209 JavaThread* _thread;
1210 public:
1211 JNIHandleMark(JavaThread* thread) : _thread(thread) {
1212 thread->push_jni_handle_block();
1213 }
1214 ~JNIHandleMark() { _thread->pop_jni_handle_block(); }
1215 };
1216
1217 #endif // SHARE_RUNTIME_JAVATHREAD_HPP