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/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 OopHandleList;
64 class OopStorage;
65 class OSThread;
66
67 class ThreadsList;
68 class ThreadSafepointState;
69 class ThreadStatistics;
70
71 class vframeArray;
72 class vframe;
73 class javaVFrame;
74
75 class JavaThread;
76 typedef void (*ThreadFunction)(JavaThread*, TRAPS);
77
78 class JavaThread: public Thread {
79 friend class VMStructs;
80 friend class JVMCIVMStructs;
81 friend class WhiteBox;
82 friend class ThreadsSMRSupport; // to access _threadObj for exiting_threads_oops_do
83 friend class HandshakeState;
84 friend class Continuation;
85 friend class Threads;
86 friend class ServiceThread; // for deferred OopHandle release access
87 private:
88 bool _on_thread_list; // Is set when this JavaThread is added to the Threads list
89
90 // All references to Java objects managed via OopHandles. These
91 // have to be released by the ServiceThread after the JavaThread has
92 // terminated - see add_oop_handles_for_release().
93 OopHandle _threadObj; // The Java level thread object
94 OopHandle _vthread; // the value returned by Thread.currentThread(): the virtual thread, if mounted, otherwise _threadObj
95 OopHandle _jvmti_vthread;
96 OopHandle _scopedValueCache;
97
98 static OopStorage* _thread_oop_storage;
99
100 #ifdef ASSERT
101 private:
102 int _java_call_counter;
103
104 public:
105 int java_call_counter() { return _java_call_counter; }
106 void inc_java_call_counter() { _java_call_counter++; }
107 void dec_java_call_counter() {
108 assert(_java_call_counter > 0, "Invalid nesting of JavaCallWrapper");
109 _java_call_counter--;
110 }
111 private: // restore original namespace restriction
112 #endif // ifdef ASSERT
113
114 JavaFrameAnchor _anchor; // Encapsulation of current java frame and it state
115
116 ThreadFunction _entry_point;
117
118 JNIEnv _jni_environment;
119
120 // Deopt support
121 DeoptResourceMark* _deopt_mark; // Holds special ResourceMark for deoptimization
122
123 CompiledMethod* _deopt_nmethod; // CompiledMethod that is currently being deoptimized
124 vframeArray* _vframe_array_head; // Holds the heap of the active vframeArrays
125 vframeArray* _vframe_array_last; // Holds last vFrameArray we popped
126 // Holds updates by JVMTI agents for compiled frames that cannot be performed immediately. They
127 // will be carried out as soon as possible which, in most cases, is just before deoptimization of
128 // the frame, when control returns to it.
129 JvmtiDeferredUpdates* _jvmti_deferred_updates;
130
131 // Handshake value for fixing 6243940. We need a place for the i2c
132 // adapter to store the callee Method*. This value is NEVER live
133 // across a gc point so it does NOT have to be gc'd
134 // The handshake is open ended since we can't be certain that it will
135 // be nulled. This is because we rarely ever see the race and end up
136 // in handle_wrong_method which is the backend of the handshake. See
137 // code in i2c adapters and handle_wrong_method.
138
139 Method* _callee_target;
140
141 // Used to pass back results to the interpreter or generated code running Java code.
142 oop _vm_result; // oop result is GC-preserved
143 Metadata* _vm_result_2; // non-oop result
144 oop _return_buffered_value; // buffered value being returned
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 volatile intptr_t _Stalled;
163
164 // For tracking the heavyweight monitor the thread is pending on.
165 ObjectMonitor* current_pending_monitor() {
166 // Use Atomic::load() to prevent data race between concurrent modification and
167 // concurrent readers, e.g. ThreadService::get_current_contended_monitor().
168 // Especially, reloading pointer from thread after null check must be prevented.
169 return Atomic::load(&_current_pending_monitor);
170 }
171 void set_current_pending_monitor(ObjectMonitor* monitor) {
172 Atomic::store(&_current_pending_monitor, monitor);
173 }
174 void set_current_pending_monitor_is_from_java(bool from_java) {
175 _current_pending_monitor_is_from_java = from_java;
176 }
177 bool current_pending_monitor_is_from_java() {
178 return _current_pending_monitor_is_from_java;
179 }
180 ObjectMonitor* current_waiting_monitor() {
181 // See the comment in current_pending_monitor() above.
182 return Atomic::load(&_current_waiting_monitor);
183 }
184 void set_current_waiting_monitor(ObjectMonitor* monitor) {
185 Atomic::store(&_current_waiting_monitor, monitor);
186 }
187
188 // JNI handle support
189 JNIHandleBlock* active_handles() const { return _active_handles; }
190 void set_active_handles(JNIHandleBlock* block) { _active_handles = block; }
191 JNIHandleBlock* free_handle_block() const { return _free_handle_block; }
192 void set_free_handle_block(JNIHandleBlock* block) { _free_handle_block = block; }
193
194 void push_jni_handle_block();
195 void pop_jni_handle_block();
196
197 private:
198 MonitorChunk* _monitor_chunks; // Contains the off stack monitors
199 // allocated during deoptimization
200 // and by JNI_MonitorEnter/Exit
201
202 enum SuspendFlags {
203 // NOTE: avoid using the sign-bit as cc generates different test code
204 // when the sign-bit is used, and sometimes incorrectly - see CR 6398077
205 _trace_flag = 0x00000004U, // call tracing backend
206 _obj_deopt = 0x00000008U // suspend for object reallocation and relocking for JVMTI agent
207 };
208
209 // various suspension related flags - atomically updated
210 volatile uint32_t _suspend_flags;
211
212 inline void set_suspend_flag(SuspendFlags f);
213 inline void clear_suspend_flag(SuspendFlags f);
214
215 public:
216 inline void set_trace_flag();
217 inline void clear_trace_flag();
218 inline void set_obj_deopt_flag();
219 inline void clear_obj_deopt_flag();
220 bool is_trace_suspend() { return (_suspend_flags & _trace_flag) != 0; }
221 bool is_obj_deopt_suspend() { return (_suspend_flags & _obj_deopt) != 0; }
222
223 // Asynchronous exception support
224 private:
225 friend class InstallAsyncExceptionHandshake;
226 friend class AsyncExceptionHandshake;
227 friend class HandshakeState;
228
229 void install_async_exception(AsyncExceptionHandshake* aec = nullptr);
230 void handle_async_exception(oop java_throwable);
231 public:
232 bool has_async_exception_condition();
233 inline void set_pending_unsafe_access_error();
234 static void send_async_exception(JavaThread* jt, oop java_throwable);
235
236 class NoAsyncExceptionDeliveryMark : public StackObj {
237 friend JavaThread;
238 JavaThread *_target;
239 inline NoAsyncExceptionDeliveryMark(JavaThread *t);
240 inline ~NoAsyncExceptionDeliveryMark();
241 };
242
243 // Safepoint support
244 public: // Expose _thread_state for SafeFetchInt()
245 volatile JavaThreadState _thread_state;
246 private:
247 SafepointMechanism::ThreadData _poll_data;
248 ThreadSafepointState* _safepoint_state; // Holds information about a thread during a safepoint
249 address _saved_exception_pc; // Saved pc of instruction where last implicit exception happened
250 NOT_PRODUCT(bool _requires_cross_modify_fence;) // State used by VerifyCrossModifyFence
251 #ifdef ASSERT
252 // Debug support for checking if code allows safepoints or not.
253 // Safepoints in the VM can happen because of allocation, invoking a VM operation, or blocking on
254 // mutex, or blocking on an object synchronizer (Java locking).
255 // If _no_safepoint_count is non-zero, then an assertion failure will happen in any of
256 // the above cases. The class NoSafepointVerifier is used to set this counter.
257 int _no_safepoint_count; // If 0, thread allow a safepoint to happen
258
259 public:
260 void inc_no_safepoint_count() { _no_safepoint_count++; }
261 void dec_no_safepoint_count() { _no_safepoint_count--; }
262 #endif // ASSERT
263 public:
264 // These functions check conditions before possibly going to a safepoint.
265 // including NoSafepointVerifier.
266 void check_for_valid_safepoint_state() NOT_DEBUG_RETURN;
267 void check_possible_safepoint() NOT_DEBUG_RETURN;
268
269 #ifdef ASSERT
270 private:
271 volatile uint64_t _visited_for_critical_count;
272
273 public:
274 void set_visited_for_critical_count(uint64_t safepoint_id) {
275 assert(_visited_for_critical_count == 0, "Must be reset before set");
276 assert((safepoint_id & 0x1) == 1, "Must be odd");
277 _visited_for_critical_count = safepoint_id;
278 }
279 void reset_visited_for_critical_count(uint64_t safepoint_id) {
280 assert(_visited_for_critical_count == safepoint_id, "Was not visited");
281 _visited_for_critical_count = 0;
282 }
283 bool was_visited_for_critical_count(uint64_t safepoint_id) const {
284 return _visited_for_critical_count == safepoint_id;
285 }
286 #endif // ASSERT
287
288 // JavaThread termination support
289 public:
290 enum TerminatedTypes {
291 _not_terminated = 0xDEAD - 3,
292 _thread_exiting, // JavaThread::exit() has been called for this thread
293 _thread_gc_barrier_detached, // thread's GC barrier has been detached
294 _thread_terminated, // JavaThread is removed from thread list
295 _vm_exited // JavaThread is still executing native code, but VM is terminated
296 // only VM_Exit can set _vm_exited
297 };
298
299 private:
300 // In general a JavaThread's _terminated field transitions as follows:
301 //
302 // _not_terminated => _thread_exiting => _thread_gc_barrier_detached => _thread_terminated
303 //
304 // _vm_exited is a special value to cover the case of a JavaThread
305 // executing native code after the VM itself is terminated.
306 //
307 // A JavaThread that fails to JNI attach has these _terminated field transitions:
308 // _not_terminated => _thread_terminated
309 //
310 volatile TerminatedTypes _terminated;
311
312 jint _in_deopt_handler; // count of deoptimization
313 // handlers thread is in
314 volatile bool _doing_unsafe_access; // Thread may fault due to unsafe access
315 bool _do_not_unlock_if_synchronized; // Do not unlock the receiver of a synchronized method (since it was
316 // never locked) when throwing an exception. Used by interpreter only.
317 #if INCLUDE_JVMTI
318 volatile bool _carrier_thread_suspended; // Carrier thread is externally suspended
319 bool _is_in_VTMS_transition; // thread is in virtual thread mount state transition
320 bool _is_in_tmp_VTMS_transition; // thread is in temporary virtual thread mount state transition
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
527 // Prepare thread and add to priority queue. If a priority is
528 // not specified, use the priority of the thread object. Threads_lock
529 // must be held while this function is called.
530 void prepare(jobject jni_thread, ThreadPriority prio=NoPriority);
531
532 void set_saved_exception_pc(address pc) { _saved_exception_pc = pc; }
533 address saved_exception_pc() { return _saved_exception_pc; }
534
535 ThreadFunction entry_point() const { return _entry_point; }
536
537 // Allocates a new Java level thread object for this thread. thread_name may be null.
538 void allocate_threadObj(Handle thread_group, const char* thread_name, bool daemon, TRAPS);
539
540 // Last frame anchor routines
541
542 JavaFrameAnchor* frame_anchor(void) { return &_anchor; }
543
544 // last_Java_sp
545 bool has_last_Java_frame() const { return _anchor.has_last_Java_frame(); }
546 intptr_t* last_Java_sp() const { return _anchor.last_Java_sp(); }
547
548 // last_Java_pc
549
550 address last_Java_pc(void) { return _anchor.last_Java_pc(); }
551
552 // Safepoint support
553 inline JavaThreadState thread_state() const;
554 inline void set_thread_state(JavaThreadState s);
555 inline void set_thread_state_fence(JavaThreadState s); // fence after setting thread state
556 inline ThreadSafepointState* safepoint_state() const;
557 inline void set_safepoint_state(ThreadSafepointState* state);
558 inline bool is_at_poll_safepoint();
559
560 // JavaThread termination and lifecycle support:
561 void smr_delete();
562 bool on_thread_list() const { return _on_thread_list; }
563 void set_on_thread_list() { _on_thread_list = true; }
564
565 // thread has called JavaThread::exit(), thread's GC barrier is detached
566 // or thread is terminated
567 bool is_exiting() const;
568 // thread's GC barrier is NOT detached and thread is NOT terminated
569 bool is_oop_safe() const;
570 // thread is terminated (no longer on the threads list); the thread must
571 // be protected by a ThreadsListHandle to avoid potential crashes.
572 bool check_is_terminated(TerminatedTypes l_terminated) const {
573 return l_terminated == _thread_terminated || l_terminated == _vm_exited;
574 }
575 bool is_terminated() const;
576 void set_terminated(TerminatedTypes t);
577
578 void block_if_vm_exited();
579
580 bool doing_unsafe_access() { return _doing_unsafe_access; }
581 void set_doing_unsafe_access(bool val) { _doing_unsafe_access = val; }
582
583 bool do_not_unlock_if_synchronized() { return _do_not_unlock_if_synchronized; }
584 void set_do_not_unlock_if_synchronized(bool val) { _do_not_unlock_if_synchronized = val; }
585
586 SafepointMechanism::ThreadData* poll_data() { return &_poll_data; }
587
588 void set_requires_cross_modify_fence(bool val) PRODUCT_RETURN NOT_PRODUCT({ _requires_cross_modify_fence = val; })
589
590 // Continuation support
591 ContinuationEntry* last_continuation() const { return _cont_entry; }
592 void set_cont_fastpath(intptr_t* x) { _cont_fastpath = x; }
593 void push_cont_fastpath(intptr_t* sp) { if (sp > _cont_fastpath) _cont_fastpath = sp; }
594 void set_cont_fastpath_thread_state(bool x) { _cont_fastpath_thread_state = (int)x; }
595 intptr_t* raw_cont_fastpath() const { return _cont_fastpath; }
596 bool cont_fastpath() const { return _cont_fastpath == nullptr && _cont_fastpath_thread_state != 0; }
597 bool cont_fastpath_thread_state() const { return _cont_fastpath_thread_state != 0; }
598
599 void inc_held_monitor_count(intx i = 1, bool jni = false);
600 void dec_held_monitor_count(intx i = 1, bool jni = false);
601
602 intx held_monitor_count() { return _held_monitor_count; }
603 intx jni_monitor_count() { return _jni_monitor_count; }
604 void clear_jni_monitor_count() { _jni_monitor_count = 0; }
605
606 inline bool is_vthread_mounted() const;
607 inline const ContinuationEntry* vthread_continuation() const;
608
609 private:
610 DEBUG_ONLY(void verify_frame_info();)
611
612 // Support for thread handshake operations
613 HandshakeState _handshake;
614 public:
615 HandshakeState* handshake_state() { return &_handshake; }
616
617 // A JavaThread can always safely operate on it self and other threads
618 // can do it safely if they are the active handshaker.
619 bool is_handshake_safe_for(Thread* th) const {
620 return _handshake.active_handshaker() == th || this == th;
621 }
622
623 // Suspend/resume support for JavaThread
624 // higher-level suspension/resume logic called by the public APIs
625 bool java_suspend();
626 bool java_resume();
627 bool is_suspended() { return _handshake.is_suspended(); }
628
629 // Check for async exception in addition to safepoint.
630 static void check_special_condition_for_native_trans(JavaThread *thread);
631
632 // Synchronize with another thread that is deoptimizing objects of the
633 // current thread, i.e. reverts optimizations based on escape analysis.
634 void wait_for_object_deoptimization();
635
636 #if INCLUDE_JVMTI
637 inline void set_carrier_thread_suspended();
638 inline void clear_carrier_thread_suspended();
639
640 bool is_carrier_thread_suspended() const {
641 return _carrier_thread_suspended;
642 }
643
644 bool is_in_VTMS_transition() const { return _is_in_VTMS_transition; }
645 bool is_in_tmp_VTMS_transition() const { return _is_in_tmp_VTMS_transition; }
646 bool is_in_any_VTMS_transition() const { return _is_in_VTMS_transition || _is_in_tmp_VTMS_transition; }
647
648 void set_is_in_VTMS_transition(bool val);
649 void toggle_is_in_tmp_VTMS_transition() { _is_in_tmp_VTMS_transition = !_is_in_tmp_VTMS_transition; };
650
651 #ifdef ASSERT
652 bool is_VTMS_transition_disabler() const { return _is_VTMS_transition_disabler; }
653 void set_is_VTMS_transition_disabler(bool val);
654 #endif
655 #endif
656
657 // Support for object deoptimization and JFR suspension
658 void handle_special_runtime_exit_condition();
659 bool has_special_runtime_exit_condition() {
660 return (_suspend_flags & (_obj_deopt JFR_ONLY(| _trace_flag))) != 0;
661 }
662
663 // Fast-locking support
664 bool is_lock_owned(address adr) const;
665
666 // Accessors for vframe array top
667 // The linked list of vframe arrays are sorted on sp. This means when we
668 // unpack the head must contain the vframe array to unpack.
669 void set_vframe_array_head(vframeArray* value) { _vframe_array_head = value; }
670 vframeArray* vframe_array_head() const { return _vframe_array_head; }
671
672 // Side structure for deferring update of java frame locals until deopt occurs
673 JvmtiDeferredUpdates* deferred_updates() const { return _jvmti_deferred_updates; }
674 void set_deferred_updates(JvmtiDeferredUpdates* du) { _jvmti_deferred_updates = du; }
675
676 // These only really exist to make debugging deopt problems simpler
677
678 void set_vframe_array_last(vframeArray* value) { _vframe_array_last = value; }
679 vframeArray* vframe_array_last() const { return _vframe_array_last; }
680
681 // The special resourceMark used during deoptimization
682
683 void set_deopt_mark(DeoptResourceMark* value) { _deopt_mark = value; }
684 DeoptResourceMark* deopt_mark(void) { return _deopt_mark; }
685
686 void set_deopt_compiled_method(CompiledMethod* nm) { _deopt_nmethod = nm; }
687 CompiledMethod* deopt_compiled_method() { return _deopt_nmethod; }
688
689 Method* callee_target() const { return _callee_target; }
690 void set_callee_target (Method* x) { _callee_target = x; }
691
692 // Oop results of vm runtime calls
693 oop vm_result() const { return _vm_result; }
694 void set_vm_result (oop x) { _vm_result = x; }
695
696 void set_vm_result_2 (Metadata* x) { _vm_result_2 = x; }
697
698 oop return_buffered_value() const { return _return_buffered_value; }
699 void set_return_buffered_value(oop val) { _return_buffered_value = val; }
700
701 MemRegion deferred_card_mark() const { return _deferred_card_mark; }
702 void set_deferred_card_mark(MemRegion mr) { _deferred_card_mark = mr; }
703
704 #if INCLUDE_JVMCI
705 jlong pending_failed_speculation() const { return _pending_failed_speculation; }
706 void set_pending_monitorenter(bool b) { _pending_monitorenter = b; }
707 void set_pending_deoptimization(int reason) { _pending_deoptimization = reason; }
708 void set_pending_failed_speculation(jlong failed_speculation) { _pending_failed_speculation = failed_speculation; }
709 void set_pending_transfer_to_interpreter(bool b) { _pending_transfer_to_interpreter = b; }
710 void set_jvmci_alternate_call_target(address a) { assert(_jvmci._alternate_call_target == nullptr, "must be"); _jvmci._alternate_call_target = a; }
711 void set_jvmci_implicit_exception_pc(address a) { assert(_jvmci._implicit_exception_pc == nullptr, "must be"); _jvmci._implicit_exception_pc = a; }
712
713 virtual bool in_retryable_allocation() const { return _in_retryable_allocation; }
714 void set_in_retryable_allocation(bool b) { _in_retryable_allocation = b; }
715
716 JVMCIRuntime* libjvmci_runtime() const { return _libjvmci_runtime; }
717 void set_libjvmci_runtime(JVMCIRuntime* rt) {
718 assert((_libjvmci_runtime == nullptr && rt != nullptr) || (_libjvmci_runtime != nullptr && rt == nullptr), "must be");
719 _libjvmci_runtime = rt;
720 }
721 #endif // INCLUDE_JVMCI
722
723 // Exception handling for compiled methods
724 oop exception_oop() const;
725 address exception_pc() const { return _exception_pc; }
726
727 void set_exception_oop(oop o);
728 void set_exception_pc(address a) { _exception_pc = a; }
729 void set_exception_handler_pc(address a) { _exception_handler_pc = a; }
730 void set_is_method_handle_return(bool value) { _is_method_handle_return = value ? 1 : 0; }
731
732 void clear_exception_oop_and_pc() {
733 set_exception_oop(nullptr);
734 set_exception_pc(nullptr);
735 }
736
737 // Check if address is in the usable part of the stack (excludes protected
738 // guard pages). Can be applied to any thread and is an approximation for
739 // using is_in_live_stack when the query has to happen from another thread.
740 bool is_in_usable_stack(address adr) const {
741 return is_in_stack_range_incl(adr, _stack_overflow_state.stack_reserved_zone_base());
742 }
743
744 // Misc. accessors/mutators
745 static ByteSize scopedValueCache_offset() { return byte_offset_of(JavaThread, _scopedValueCache); }
746
747 // For assembly stub generation
748 static ByteSize threadObj_offset() { return byte_offset_of(JavaThread, _threadObj); }
749 static ByteSize vthread_offset() { return byte_offset_of(JavaThread, _vthread); }
750 static ByteSize jni_environment_offset() { return byte_offset_of(JavaThread, _jni_environment); }
751 static ByteSize pending_jni_exception_check_fn_offset() {
752 return byte_offset_of(JavaThread, _pending_jni_exception_check_fn);
753 }
754 static ByteSize last_Java_sp_offset() {
755 return byte_offset_of(JavaThread, _anchor) + JavaFrameAnchor::last_Java_sp_offset();
756 }
757 static ByteSize last_Java_pc_offset() {
758 return byte_offset_of(JavaThread, _anchor) + JavaFrameAnchor::last_Java_pc_offset();
759 }
760 static ByteSize frame_anchor_offset() {
761 return byte_offset_of(JavaThread, _anchor);
762 }
763 static ByteSize callee_target_offset() { return byte_offset_of(JavaThread, _callee_target); }
764 static ByteSize vm_result_offset() { return byte_offset_of(JavaThread, _vm_result); }
765 static ByteSize vm_result_2_offset() { return byte_offset_of(JavaThread, _vm_result_2); }
766 static ByteSize return_buffered_value_offset() { return byte_offset_of(JavaThread, _return_buffered_value); }
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 #endif
820
821 // Returns the jni environment for this thread
822 JNIEnv* jni_environment() { return &_jni_environment; }
823
824 // Returns the current thread as indicated by the given JNIEnv.
825 // We don't assert it is Thread::current here as that is done at the
826 // external JNI entry points where the JNIEnv is passed into the VM.
827 static JavaThread* thread_from_jni_environment(JNIEnv* env) {
828 JavaThread* current = reinterpret_cast<JavaThread*>(((intptr_t)env - in_bytes(jni_environment_offset())));
829 // We can't normally get here in a thread that has completed its
830 // execution and so "is_terminated", except when the call is from
831 // AsyncGetCallTrace, which can be triggered by a signal at any point in
832 // a thread's lifecycle. A thread is also considered terminated if the VM
833 // has exited, so we have to check this and block in case this is a daemon
834 // thread returning to the VM (the JNI DirectBuffer entry points rely on
835 // this).
836 if (current->is_terminated()) {
837 current->block_if_vm_exited();
838 }
839 return current;
840 }
841
842 // JNI critical regions. These can nest.
843 bool in_critical() { return _jni_active_critical > 0; }
844 bool in_last_critical() { return _jni_active_critical == 1; }
845 inline void enter_critical();
846 void exit_critical() {
847 assert(Thread::current() == this, "this must be current thread");
848 _jni_active_critical--;
849 assert(_jni_active_critical >= 0, "JNI critical nesting problem?");
850 }
851
852 // Checked JNI: is the programmer required to check for exceptions, if so specify
853 // which function name. Returning to a Java frame should implicitly clear the
854 // pending check, this is done for Native->Java transitions (i.e. user JNI code).
855 // VM->Java transitions are not cleared, it is expected that JNI code enclosed
856 // within ThreadToNativeFromVM makes proper exception checks (i.e. VM internal).
857 bool is_pending_jni_exception_check() const { return _pending_jni_exception_check_fn != nullptr; }
858 void clear_pending_jni_exception_check() { _pending_jni_exception_check_fn = nullptr; }
859 const char* get_pending_jni_exception_check() const { return _pending_jni_exception_check_fn; }
860 void set_pending_jni_exception_check(const char* fn_name) { _pending_jni_exception_check_fn = (char*) fn_name; }
861
862 // For deadlock detection
863 int depth_first_number() { return _depth_first_number; }
864 void set_depth_first_number(int dfn) { _depth_first_number = dfn; }
865
866 private:
867 void set_monitor_chunks(MonitorChunk* monitor_chunks) { _monitor_chunks = monitor_chunks; }
868
869 public:
870 MonitorChunk* monitor_chunks() const { return _monitor_chunks; }
871 void add_monitor_chunk(MonitorChunk* chunk);
872 void remove_monitor_chunk(MonitorChunk* chunk);
873 bool in_deopt_handler() const { return _in_deopt_handler > 0; }
874 void inc_in_deopt_handler() { _in_deopt_handler++; }
875 void dec_in_deopt_handler() {
876 assert(_in_deopt_handler > 0, "mismatched deopt nesting");
877 if (_in_deopt_handler > 0) { // robustness
878 _in_deopt_handler--;
879 }
880 }
881
882 private:
883 void set_entry_point(ThreadFunction entry_point) { _entry_point = entry_point; }
884
885 // factor out low-level mechanics for use in both normal and error cases
886 const char* get_thread_name_string(char* buf = nullptr, int buflen = 0) const;
887
888 public:
889
890 // Frame iteration; calls the function f for all frames on the stack
891 void frames_do(void f(frame*, const RegisterMap*));
892
893 // Memory operations
894 void oops_do_frames(OopClosure* f, CodeBlobClosure* cf);
895 void oops_do_no_frames(OopClosure* f, CodeBlobClosure* cf);
896
897 // GC operations
898 virtual void nmethods_do(CodeBlobClosure* cf);
899
900 // RedefineClasses Support
901 void metadata_do(MetadataClosure* f);
902
903 // Debug method asserting thread states are correct during a handshake operation.
904 DEBUG_ONLY(void verify_states_for_handshake();)
905
906 // Misc. operations
907 const char* name() const;
908 const char* type_name() const { return "JavaThread"; }
909 static const char* name_for(oop thread_obj);
910
911 void print_on(outputStream* st, bool print_extended_info) const;
912 void print_on(outputStream* st) const { print_on(st, false); }
913 void print() const;
914 void print_thread_state_on(outputStream*) const;
915 void print_on_error(outputStream* st, char* buf, int buflen) const;
916 void print_name_on_error(outputStream* st, char* buf, int buflen) const;
917 void verify();
918
919 // Accessing frames
920 frame last_frame() {
921 _anchor.make_walkable();
922 return pd_last_frame();
923 }
924 javaVFrame* last_java_vframe(RegisterMap* reg_map) { return last_java_vframe(last_frame(), reg_map); }
925
926 frame carrier_last_frame(RegisterMap* reg_map);
927 javaVFrame* carrier_last_java_vframe(RegisterMap* reg_map) { return last_java_vframe(carrier_last_frame(reg_map), reg_map); }
928
929 frame vthread_last_frame();
930 javaVFrame* vthread_last_java_vframe(RegisterMap* reg_map) { return last_java_vframe(vthread_last_frame(), reg_map); }
931
932 frame platform_thread_last_frame(RegisterMap* reg_map);
933 javaVFrame* platform_thread_last_java_vframe(RegisterMap* reg_map) {
934 return last_java_vframe(platform_thread_last_frame(reg_map), reg_map);
935 }
936
937 javaVFrame* last_java_vframe(const frame f, RegisterMap* reg_map);
938
939 // Returns method at 'depth' java or native frames down the stack
940 // Used for security checks
941 Klass* security_get_caller_class(int depth);
942
943 // Print stack trace in external format
944 // These variants print carrier/platform thread information only.
945 void print_stack_on(outputStream* st);
946 void print_stack() { print_stack_on(tty); }
947 // This prints the currently mounted virtual thread.
948 void print_vthread_stack_on(outputStream* st);
949 // This prints the active stack: either carrier/platform or virtual.
950 void print_active_stack_on(outputStream* st);
951 // Print current stack trace for checked JNI warnings and JNI fatal errors.
952 // This is the external format from above, but selecting the platform
953 // or vthread as applicable.
954 void print_jni_stack();
955
956 // Print stack traces in various internal formats
957 void trace_stack() PRODUCT_RETURN;
958 void trace_stack_from(vframe* start_vf) PRODUCT_RETURN;
959 void trace_frames() PRODUCT_RETURN;
960
961 // Print an annotated view of the stack frames
962 void print_frame_layout(int depth = 0, bool validate_only = false) NOT_DEBUG_RETURN;
963 void validate_frame_layout() {
964 print_frame_layout(0, true);
965 }
966
967 // Function for testing deoptimization
968 void deoptimize();
969 void make_zombies();
970
971 void deoptimize_marked_methods();
972
973 public:
974 // Returns the running thread as a JavaThread
975 static JavaThread* current() {
976 return JavaThread::cast(Thread::current());
977 }
978
979 // Returns the current thread as a JavaThread, or nullptr if not attached
980 static inline JavaThread* current_or_null();
981
982 // Casts
983 static JavaThread* cast(Thread* t) {
984 assert(t->is_Java_thread(), "incorrect cast to JavaThread");
985 return static_cast<JavaThread*>(t);
986 }
987
988 static const JavaThread* cast(const Thread* t) {
989 assert(t->is_Java_thread(), "incorrect cast to const JavaThread");
990 return static_cast<const JavaThread*>(t);
991 }
992
993 // Returns the active Java thread. Do not use this if you know you are calling
994 // from a JavaThread, as it's slower than JavaThread::current. If called from
995 // the VMThread, it also returns the JavaThread that instigated the VMThread's
996 // operation. You may not want that either.
997 static JavaThread* active();
998
999 protected:
1000 virtual void pre_run();
1001 virtual void run();
1002 void thread_main_inner();
1003 virtual void post_run();
1004
1005 public:
1006 // Thread local information maintained by JVMTI.
1007 void set_jvmti_thread_state(JvmtiThreadState *value) { _jvmti_thread_state = value; }
1008 // A JvmtiThreadState is lazily allocated. This jvmti_thread_state()
1009 // getter is used to get this JavaThread's JvmtiThreadState if it has
1010 // one which means null can be returned. JvmtiThreadState::state_for()
1011 // is used to get the specified JavaThread's JvmtiThreadState if it has
1012 // one or it allocates a new JvmtiThreadState for the JavaThread and
1013 // returns it. JvmtiThreadState::state_for() will return null only if
1014 // the specified JavaThread is exiting.
1015 JvmtiThreadState *jvmti_thread_state() const { return _jvmti_thread_state; }
1016 static ByteSize jvmti_thread_state_offset() { return byte_offset_of(JavaThread, _jvmti_thread_state); }
1017
1018 #if INCLUDE_JVMTI
1019 // Rebind JVMTI thread state from carrier to virtual or from virtual to carrier.
1020 JvmtiThreadState *rebind_to_jvmti_thread_state_of(oop thread_oop);
1021 #endif
1022
1023 // JVMTI PopFrame support
1024 // Setting and clearing popframe_condition
1025 // All of these enumerated values are bits. popframe_pending
1026 // indicates that a PopFrame() has been requested and not yet been
1027 // completed. popframe_processing indicates that that PopFrame() is in
1028 // the process of being completed. popframe_force_deopt_reexecution_bit
1029 // indicates that special handling is required when returning to a
1030 // deoptimized caller.
1031 enum PopCondition {
1032 popframe_inactive = 0x00,
1033 popframe_pending_bit = 0x01,
1034 popframe_processing_bit = 0x02,
1035 popframe_force_deopt_reexecution_bit = 0x04
1036 };
1037 PopCondition popframe_condition() { return (PopCondition) _popframe_condition; }
1038 void set_popframe_condition(PopCondition c) { _popframe_condition = c; }
1039 void set_popframe_condition_bit(PopCondition c) { _popframe_condition |= c; }
1040 void clear_popframe_condition() { _popframe_condition = popframe_inactive; }
1041 static ByteSize popframe_condition_offset() { return byte_offset_of(JavaThread, _popframe_condition); }
1042 bool has_pending_popframe() { return (popframe_condition() & popframe_pending_bit) != 0; }
1043 bool popframe_forcing_deopt_reexecution() { return (popframe_condition() & popframe_force_deopt_reexecution_bit) != 0; }
1044
1045 bool pop_frame_in_process(void) { return ((_popframe_condition & popframe_processing_bit) != 0); }
1046 void set_pop_frame_in_process(void) { _popframe_condition |= popframe_processing_bit; }
1047 void clr_pop_frame_in_process(void) { _popframe_condition &= ~popframe_processing_bit; }
1048
1049 int frames_to_pop_failed_realloc() const { return _frames_to_pop_failed_realloc; }
1050 void set_frames_to_pop_failed_realloc(int nb) { _frames_to_pop_failed_realloc = nb; }
1051 void dec_frames_to_pop_failed_realloc() { _frames_to_pop_failed_realloc--; }
1052
1053 private:
1054 // Saved incoming arguments to popped frame.
1055 // Used only when popped interpreted frame returns to deoptimized frame.
1056 void* _popframe_preserved_args;
1057 int _popframe_preserved_args_size;
1058
1059 public:
1060 void popframe_preserve_args(ByteSize size_in_bytes, void* start);
1061 void* popframe_preserved_args();
1062 ByteSize popframe_preserved_args_size();
1063 WordSize popframe_preserved_args_size_in_words();
1064 void popframe_free_preserved_args();
1065
1066
1067 private:
1068 JvmtiThreadState *_jvmti_thread_state;
1069
1070 // Used by the interpreter in fullspeed mode for frame pop, method
1071 // entry, method exit and single stepping support. This field is
1072 // only set to non-zero at a safepoint or using a direct handshake
1073 // (see EnterInterpOnlyModeClosure).
1074 // It can be set to zero asynchronously to this threads execution (i.e., without
1075 // safepoint/handshake or a lock) so we have to be very careful.
1076 // Accesses by other threads are synchronized using JvmtiThreadState_lock though.
1077 int _interp_only_mode;
1078
1079 public:
1080 // used by the interpreter for fullspeed debugging support (see above)
1081 static ByteSize interp_only_mode_offset() { return byte_offset_of(JavaThread, _interp_only_mode); }
1082 bool is_interp_only_mode() { return (_interp_only_mode != 0); }
1083 int get_interp_only_mode() { return _interp_only_mode; }
1084 int set_interp_only_mode(int val) { return _interp_only_mode = val; }
1085 void increment_interp_only_mode() { ++_interp_only_mode; }
1086 void decrement_interp_only_mode() { --_interp_only_mode; }
1087
1088 // support for cached flag that indicates whether exceptions need to be posted for this thread
1089 // if this is false, we can avoid deoptimizing when events are thrown
1090 // this gets set to reflect whether jvmtiExport::post_exception_throw would actually do anything
1091 private:
1092 int _should_post_on_exceptions_flag;
1093
1094 public:
1095 void set_should_post_on_exceptions_flag(int val) { _should_post_on_exceptions_flag = val; }
1096
1097 private:
1098 ThreadStatistics *_thread_stat;
1099
1100 public:
1101 ThreadStatistics* get_thread_stat() const { return _thread_stat; }
1102
1103 // Return a blocker object for which this thread is blocked parking.
1104 oop current_park_blocker();
1105
1106 private:
1107 static size_t _stack_size_at_create;
1108
1109 public:
1110 static inline size_t stack_size_at_create(void) {
1111 return _stack_size_at_create;
1112 }
1113 static inline void set_stack_size_at_create(size_t value) {
1114 _stack_size_at_create = value;
1115 }
1116
1117 // Machine dependent stuff
1118 #include OS_CPU_HEADER(javaThread)
1119
1120 // JSR166 per-thread parker
1121 private:
1122 Parker _parker;
1123 public:
1124 Parker* parker() { return &_parker; }
1125
1126 public:
1127 // clearing/querying jni attach status
1128 bool is_attaching_via_jni() const { return _jni_attach_state == _attaching_via_jni; }
1129 bool has_attached_via_jni() const { return is_attaching_via_jni() || _jni_attach_state == _attached_via_jni; }
1130 inline void set_done_attaching_via_jni();
1131
1132 // Stack dump assistance:
1133 // Track the class we want to initialize but for which we have to wait
1134 // on its init_lock() because it is already being initialized.
1135 void set_class_to_be_initialized(InstanceKlass* k);
1136 InstanceKlass* class_to_be_initialized() const;
1137
1138 private:
1139 InstanceKlass* _class_to_be_initialized;
1140
1141 // java.lang.Thread.sleep support
1142 ParkEvent * _SleepEvent;
1143 public:
1144 bool sleep(jlong millis);
1145 bool sleep_nanos(jlong nanos);
1146
1147 // java.lang.Thread interruption support
1148 void interrupt();
1149 bool is_interrupted(bool clear_interrupted);
1150
1151 private:
1152 LockStack _lock_stack;
1153
1154 public:
1155 LockStack& lock_stack() { return _lock_stack; }
1156
1157 static ByteSize lock_stack_offset() { return byte_offset_of(JavaThread, _lock_stack); }
1158 // Those offsets are used in code generators to access the LockStack that is embedded in this
1159 // JavaThread structure. Those accesses are relative to the current thread, which
1160 // is typically in a dedicated register.
1161 static ByteSize lock_stack_top_offset() { return lock_stack_offset() + LockStack::top_offset(); }
1162 static ByteSize lock_stack_base_offset() { return lock_stack_offset() + LockStack::base_offset(); }
1163
1164 static OopStorage* thread_oop_storage();
1165
1166 static void verify_cross_modify_fence_failure(JavaThread *thread) PRODUCT_RETURN;
1167
1168 // Helper function to create the java.lang.Thread object for a
1169 // VM-internal thread. The thread will have the given name and be
1170 // part of the System ThreadGroup.
1171 static Handle create_system_thread_object(const char* name, TRAPS);
1172
1173 // Helper function to start a VM-internal daemon thread.
1174 // E.g. ServiceThread, NotificationThread, CompilerThread etc.
1175 static void start_internal_daemon(JavaThread* current, JavaThread* target,
1176 Handle thread_oop, ThreadPriority prio);
1177
1178 // Helper function to do vm_exit_on_initialization for osthread
1179 // resource allocation failure.
1180 static void vm_exit_on_osthread_failure(JavaThread* thread);
1181
1182 // Deferred OopHandle release support
1183 private:
1184 // List of OopHandles to be released - guarded by the Service_lock.
1185 static OopHandleList* _oop_handle_list;
1186 // Add our OopHandles to the list for the service thread to release.
1187 void add_oop_handles_for_release();
1188 // Called by the ServiceThread to release the OopHandles.
1189 static void release_oop_handles();
1190 // Called by the ServiceThread to poll if there are any OopHandles to release.
1191 // Called when holding the Service_lock.
1192 static bool has_oop_handles_to_release() {
1193 return _oop_handle_list != nullptr;
1194 }
1195 };
1196
1197 inline JavaThread* JavaThread::current_or_null() {
1198 Thread* current = Thread::current_or_null();
1199 return current != nullptr ? JavaThread::cast(current) : nullptr;
1200 }
1201
1202 class UnlockFlagSaver {
1203 private:
1204 JavaThread* _thread;
1205 bool _do_not_unlock;
1206 public:
1207 UnlockFlagSaver(JavaThread* t) {
1208 _thread = t;
1209 _do_not_unlock = t->do_not_unlock_if_synchronized();
1210 t->set_do_not_unlock_if_synchronized(false);
1211 }
1212 ~UnlockFlagSaver() {
1213 _thread->set_do_not_unlock_if_synchronized(_do_not_unlock);
1214 }
1215 };
1216
1217 class JNIHandleMark : public StackObj {
1218 JavaThread* _thread;
1219 public:
1220 JNIHandleMark(JavaThread* thread) : _thread(thread) {
1221 thread->push_jni_handle_block();
1222 }
1223 ~JNIHandleMark() { _thread->pop_jni_handle_block(); }
1224 };
1225
1226 #endif // SHARE_RUNTIME_JAVATHREAD_HPP