1 /*
2 * Copyright (c) 1997, 2024, Oracle and/or its affiliates. All rights reserved.
3 * Copyright (c) 2021, Azul Systems, Inc. All rights reserved.
4 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
5 *
6 * This code is free software; you can redistribute it and/or modify it
7 * under the terms of the GNU General Public License version 2 only, as
8 * published by the Free Software Foundation.
9 *
10 * This code is distributed in the hope that it will be useful, but WITHOUT
11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
13 * version 2 for more details (a copy is included in the LICENSE file that
14 * accompanied this code).
15 *
16 * You should have received a copy of the GNU General Public License version
17 * 2 along with this work; if not, write to the Free Software Foundation,
18 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
19 *
20 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
21 * or visit www.oracle.com if you need additional information or have any
22 * questions.
23 *
24 */
25
26 #ifndef SHARE_RUNTIME_JAVATHREAD_HPP
27 #define SHARE_RUNTIME_JAVATHREAD_HPP
28
29 #include "jni.h"
30 #include "memory/allocation.hpp"
31 #include "oops/oop.hpp"
32 #include "oops/oopHandle.hpp"
33 #include "runtime/frame.hpp"
34 #include "runtime/globals.hpp"
35 #include "runtime/handshake.hpp"
36 #include "runtime/javaFrameAnchor.hpp"
37 #include "runtime/lockStack.hpp"
38 #include "runtime/park.hpp"
39 #include "runtime/safepointMechanism.hpp"
40 #include "runtime/stackWatermarkSet.hpp"
41 #include "runtime/stackOverflow.hpp"
42 #include "runtime/thread.hpp"
43 #include "runtime/threadHeapSampler.hpp"
44 #include "runtime/threadStatisticalInfo.hpp"
45 #include "utilities/exceptions.hpp"
46 #include "utilities/globalDefinitions.hpp"
47 #include "utilities/macros.hpp"
48 #if INCLUDE_JFR
49 #include "jfr/support/jfrThreadExtension.hpp"
50 #endif
51
52 class AsyncExceptionHandshake;
53 class ContinuationEntry;
54 class DeoptResourceMark;
55 class InternalOOMEMark;
56 class JNIHandleBlock;
57 class JVMCIRuntime;
58
59 class JvmtiDeferredUpdates;
60 class JvmtiSampledObjectAllocEventCollector;
61 class JvmtiThreadState;
62
63 class Metadata;
64 class ObjectMonitor;
65 class OopHandleList;
66 class OopStorage;
67 class OSThread;
68
69 class ThreadsList;
70 class ThreadSafepointState;
71 class ThreadStatistics;
72
73 class vframeArray;
74 class vframe;
75 class javaVFrame;
76
77 class JavaThread;
78 typedef void (*ThreadFunction)(JavaThread*, TRAPS);
79
80 class JavaThread: public Thread {
81 friend class VMStructs;
82 friend class JVMCIVMStructs;
83 friend class WhiteBox;
84 friend class ThreadsSMRSupport; // to access _threadObj for exiting_threads_oops_do
85 friend class HandshakeState;
86 friend class Continuation;
87 friend class Threads;
88 friend class ServiceThread; // for deferred OopHandle release access
89 private:
90 bool _on_thread_list; // Is set when this JavaThread is added to the Threads list
91
92 // All references to Java objects managed via OopHandles. These
93 // have to be released by the ServiceThread after the JavaThread has
94 // terminated - see add_oop_handles_for_release().
95 OopHandle _threadObj; // The Java level thread object
96 OopHandle _vthread; // the value returned by Thread.currentThread(): the virtual thread, if mounted, otherwise _threadObj
97 OopHandle _jvmti_vthread;
98 OopHandle _scopedValueCache;
99
100 static OopStorage* _thread_oop_storage;
101
102 #ifdef ASSERT
103 private:
104 int _java_call_counter;
105
106 public:
107 int java_call_counter() { return _java_call_counter; }
108 void inc_java_call_counter() { _java_call_counter++; }
109 void dec_java_call_counter() {
110 assert(_java_call_counter > 0, "Invalid nesting of JavaCallWrapper");
111 _java_call_counter--;
112 }
113 private: // restore original namespace restriction
114 #endif // ifdef ASSERT
115
116 JavaFrameAnchor _anchor; // Encapsulation of current java frame and it state
117
118 ThreadFunction _entry_point;
119
120 JNIEnv _jni_environment;
121
122 // Deopt support
123 DeoptResourceMark* _deopt_mark; // Holds special ResourceMark for deoptimization
124
125 nmethod* _deopt_nmethod; // nmethod that is currently being deoptimized
126 vframeArray* _vframe_array_head; // Holds the heap of the active vframeArrays
127 vframeArray* _vframe_array_last; // Holds last vFrameArray we popped
128 // Holds updates by JVMTI agents for compiled frames that cannot be performed immediately. They
129 // will be carried out as soon as possible which, in most cases, is just before deoptimization of
130 // the frame, when control returns to it.
131 JvmtiDeferredUpdates* _jvmti_deferred_updates;
132
133 // Handshake value for fixing 6243940. We need a place for the i2c
134 // adapter to store the callee Method*. This value is NEVER live
135 // across a gc point so it does NOT have to be gc'd
136 // The handshake is open ended since we can't be certain that it will
137 // be nulled. This is because we rarely ever see the race and end up
138 // in handle_wrong_method which is the backend of the handshake. See
139 // code in i2c adapters and handle_wrong_method.
140
141 Method* _callee_target;
142
143 // Used to pass back results to the interpreter or generated code running Java code.
144 oop _vm_result; // oop result is GC-preserved
145 Metadata* _vm_result_2; // non-oop result
146 oop _return_buffered_value; // buffered value being returned
147
148 // See ReduceInitialCardMarks: this holds the precise space interval of
149 // the most recent slow path allocation for which compiled code has
150 // elided card-marks for performance along the fast-path.
151 MemRegion _deferred_card_mark;
152
153 ObjectMonitor* volatile _current_pending_monitor; // ObjectMonitor this thread is waiting to lock
154 bool _current_pending_monitor_is_from_java; // locking is from Java code
155 ObjectMonitor* volatile _current_waiting_monitor; // ObjectMonitor on which this thread called Object.wait()
156
157 // Active_handles points to a block of handles
158 JNIHandleBlock* _active_handles;
159
160 // One-element thread local free list
161 JNIHandleBlock* _free_handle_block;
162
163 public:
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 enum SuspendFlags {
199 // NOTE: avoid using the sign-bit as cc generates different test code
200 // when the sign-bit is used, and sometimes incorrectly - see CR 6398077
201 _trace_flag = 0x00000004U, // call tracing backend
202 _obj_deopt = 0x00000008U // suspend for object reallocation and relocking for JVMTI agent
203 };
204
205 // various suspension related flags - atomically updated
206 volatile uint32_t _suspend_flags;
207
208 inline void set_suspend_flag(SuspendFlags f);
209 inline void clear_suspend_flag(SuspendFlags f);
210
211 public:
212 inline void set_trace_flag();
213 inline void clear_trace_flag();
214 inline void set_obj_deopt_flag();
215 inline void clear_obj_deopt_flag();
216 bool is_trace_suspend() { return (_suspend_flags & _trace_flag) != 0; }
217 bool is_obj_deopt_suspend() { return (_suspend_flags & _obj_deopt) != 0; }
218
219 // Asynchronous exception support
220 private:
221 friend class InstallAsyncExceptionHandshake;
222 friend class AsyncExceptionHandshake;
223 friend class HandshakeState;
224
225 void handle_async_exception(oop java_throwable);
226 public:
227 void install_async_exception(AsyncExceptionHandshake* aec = nullptr);
228 bool has_async_exception_condition();
229 inline void set_pending_unsafe_access_error();
230 static void send_async_exception(JavaThread* jt, oop java_throwable);
231
232 class NoAsyncExceptionDeliveryMark : public StackObj {
233 friend JavaThread;
234 JavaThread *_target;
235 inline NoAsyncExceptionDeliveryMark(JavaThread *t);
236 inline ~NoAsyncExceptionDeliveryMark();
237 };
238
239 // Safepoint support
240 public: // Expose _thread_state for SafeFetchInt()
241 volatile JavaThreadState _thread_state;
242 ThreadSafepointState* _safepoint_state; // Holds information about a thread during a safepoint
243 address _saved_exception_pc; // Saved pc of instruction where last implicit exception happened
244 NOT_PRODUCT(bool _requires_cross_modify_fence;) // State used by VerifyCrossModifyFence
245 #ifdef ASSERT
246 // Debug support for checking if code allows safepoints or not.
247 // Safepoints in the VM can happen because of allocation, invoking a VM operation, or blocking on
248 // mutex, or blocking on an object synchronizer (Java locking).
249 // If _no_safepoint_count is non-zero, then an assertion failure will happen in any of
250 // the above cases. The class NoSafepointVerifier is used to set this counter.
251 int _no_safepoint_count; // If 0, thread allow a safepoint to happen
252
253 public:
254 void inc_no_safepoint_count() { _no_safepoint_count++; }
255 void dec_no_safepoint_count() { _no_safepoint_count--; }
256 bool is_in_no_safepoint_scope() { return _no_safepoint_count > 0; }
257 #endif // ASSERT
258 public:
259 // These functions check conditions before possibly going to a safepoint.
260 // including NoSafepointVerifier.
261 void check_for_valid_safepoint_state() NOT_DEBUG_RETURN;
262 void check_possible_safepoint() NOT_DEBUG_RETURN;
263
264 #ifdef ASSERT
265 private:
266 volatile uint64_t _visited_for_critical_count;
267
268 public:
269 void set_visited_for_critical_count(uint64_t safepoint_id) {
270 assert(_visited_for_critical_count == 0, "Must be reset before set");
271 assert((safepoint_id & 0x1) == 1, "Must be odd");
272 _visited_for_critical_count = safepoint_id;
273 }
274 void reset_visited_for_critical_count(uint64_t safepoint_id) {
275 assert(_visited_for_critical_count == safepoint_id, "Was not visited");
276 _visited_for_critical_count = 0;
277 }
278 bool was_visited_for_critical_count(uint64_t safepoint_id) const {
279 return _visited_for_critical_count == safepoint_id;
280 }
281 #endif // ASSERT
282
283 // JavaThread termination support
284 public:
285 enum TerminatedTypes {
286 _not_terminated = 0xDEAD - 3,
287 _thread_exiting, // JavaThread::exit() has been called for this thread
288 _thread_gc_barrier_detached, // thread's GC barrier has been detached
289 _thread_terminated, // JavaThread is removed from thread list
290 _vm_exited // JavaThread is still executing native code, but VM is terminated
291 // only VM_Exit can set _vm_exited
292 };
293
294 private:
295 // In general a JavaThread's _terminated field transitions as follows:
296 //
297 // _not_terminated => _thread_exiting => _thread_gc_barrier_detached => _thread_terminated
298 //
299 // _vm_exited is a special value to cover the case of a JavaThread
300 // executing native code after the VM itself is terminated.
301 //
302 // A JavaThread that fails to JNI attach has these _terminated field transitions:
303 // _not_terminated => _thread_terminated
304 //
305 volatile TerminatedTypes _terminated;
306
307 jint _in_deopt_handler; // count of deoptimization
308 // handlers thread is in
309 volatile bool _doing_unsafe_access; // Thread may fault due to unsafe access
310 bool _do_not_unlock_if_synchronized; // Do not unlock the receiver of a synchronized method (since it was
311 // never locked) when throwing an exception. Used by interpreter only.
312 #if INCLUDE_JVMTI
313 volatile bool _carrier_thread_suspended; // Carrier thread is externally suspended
314 bool _is_in_VTMS_transition; // thread is in virtual thread mount state transition
315 bool _is_in_tmp_VTMS_transition; // thread is in temporary virtual thread mount state transition
316 bool _is_disable_suspend; // JVMTI suspend is temporarily disabled; used on current thread only
317 bool _VTMS_transition_mark; // used for sync between VTMS transitions and disablers
318 #ifdef ASSERT
319 bool _is_VTMS_transition_disabler; // thread currently disabled VTMS transitions
320 #endif
321 #endif
322
323 // JNI attach states:
324 enum JNIAttachStates {
325 _not_attaching_via_jni = 1, // thread is not attaching via JNI
326 _attaching_via_jni, // thread is attaching via JNI
327 _attached_via_jni // thread has attached via JNI
328 };
329
330 // A regular JavaThread's _jni_attach_state is _not_attaching_via_jni.
331 // A native thread that is attaching via JNI starts with a value
332 // of _attaching_via_jni and transitions to _attached_via_jni.
333 volatile JNIAttachStates _jni_attach_state;
334
335 // In scope of an InternalOOMEMark?
336 bool _is_in_internal_oome_mark;
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 // An id of a speculation that JVMCI compiled code can use to further describe and
353 // uniquely identify the speculative optimization guarded by an uncommon trap.
354 // See JVMCINMethodData::SPECULATION_LENGTH_BITS for further details.
355 jlong _pending_failed_speculation;
356
357 // These fields are mutually exclusive in terms of live ranges.
358 union {
359 // Communicates the pc at which the most recent implicit exception occurred
360 // from the signal handler to a deoptimization stub.
361 address _implicit_exception_pc;
362
363 // Communicates an alternative call target to an i2c stub from a JavaCall .
364 address _alternate_call_target;
365 } _jvmci;
366
367 // The JVMCIRuntime in a JVMCI shared library
368 JVMCIRuntime* _libjvmci_runtime;
369
370 // Support for high precision, thread sensitive counters in JVMCI compiled code.
371 jlong* _jvmci_counters;
372
373 // Fast thread locals for use by JVMCI
374 jlong _jvmci_reserved0;
375 jlong _jvmci_reserved1;
376 oop _jvmci_reserved_oop0;
377
378 // This field is used to keep an nmethod visible to the GC so that it and its contained oops can
379 // be kept alive
380 nmethod* _live_nmethod;
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 void set_live_nmethod(nmethod* nm) {
415 assert(_live_nmethod == nullptr, "only one");
416 _live_nmethod = nm;
417 }
418
419 void clear_live_nmethod() {
420 _live_nmethod = nullptr;
421 }
422
423 private:
424 #endif // INCLUDE_JVMCI
425
426 StackOverflow _stack_overflow_state;
427
428 void pretouch_stack();
429
430 // Compiler exception handling (NOTE: The _exception_oop is *NOT* the same as _pending_exception. It is
431 // used to temp. parsing values into and out of the runtime system during exception handling for compiled
432 // code)
433 volatile oop _exception_oop; // Exception thrown in compiled code
434 volatile address _exception_pc; // PC where exception happened
435 volatile address _exception_handler_pc; // PC for handler of exception
436 volatile int _is_method_handle_return; // true (== 1) if the current exception PC is a MethodHandle call site.
437
438 private:
439 // support for JNI critical regions
440 jint _jni_active_critical; // count of entries into JNI critical region
441
442 // Checked JNI: function name requires exception check
443 char* _pending_jni_exception_check_fn;
444
445 // For deadlock detection.
446 int _depth_first_number;
447
448 // JVMTI PopFrame support
449 // This is set to popframe_pending to signal that top Java frame should be popped immediately
450 int _popframe_condition;
451
452 // If reallocation of scalar replaced objects fails, we throw OOM
453 // and during exception propagation, pop the top
454 // _frames_to_pop_failed_realloc frames, the ones that reference
455 // failed reallocations.
456 int _frames_to_pop_failed_realloc;
457
458 ContinuationEntry* _cont_entry;
459 intptr_t* _cont_fastpath; // the sp of the oldest known interpreted/call_stub frame inside the
460 // continuation that we know about
461 int _cont_fastpath_thread_state; // whether global thread state allows continuation fastpath (JVMTI)
462
463 // It's signed for error detection.
464 intx _held_monitor_count; // used by continuations for fast lock detection
465 intx _jni_monitor_count;
466 ObjectMonitor* _unlocked_inflated_monitor;
467
468 private:
469
470 friend class VMThread;
471 friend class ThreadWaitTransition;
472 friend class VM_Exit;
473
474 // Stack watermark barriers.
475 StackWatermarks _stack_watermarks;
476
477 public:
478 inline StackWatermarks* stack_watermarks() { return &_stack_watermarks; }
479
480 public:
481 // Constructor
482 JavaThread(MemTag mem_tag = mtThread); // delegating constructor
483 JavaThread(ThreadFunction entry_point, size_t stack_size = 0, MemTag mem_tag = mtThread);
484 ~JavaThread();
485
486 // Factory method to create a new JavaThread whose attach state is "is attaching"
487 static JavaThread* create_attaching_thread();
488
489 #ifdef ASSERT
490 // verify this JavaThread hasn't be published in the Threads::list yet
491 void verify_not_published();
492 #endif // ASSERT
493
494 StackOverflow* stack_overflow_state() { return &_stack_overflow_state; }
495
496 //JNI functiontable getter/setter for JVMTI jni function table interception API.
497 void set_jni_functions(struct JNINativeInterface_* functionTable) {
498 _jni_environment.functions = functionTable;
499 }
500 struct JNINativeInterface_* get_jni_functions() {
501 return (struct JNINativeInterface_ *)_jni_environment.functions;
502 }
503
504 // This function is called at thread creation to allow
505 // platform specific thread variables to be initialized.
506 void cache_global_variables();
507
508 // Executes Shutdown.shutdown()
509 void invoke_shutdown_hooks();
510
511 // Cleanup on thread exit
512 enum ExitType {
513 normal_exit,
514 jni_detach
515 };
516 void exit(bool destroy_vm, ExitType exit_type = normal_exit);
517
518 void cleanup_failed_attach_current_thread(bool is_daemon);
519
520 // Testers
521 virtual bool is_Java_thread() const { return true; }
522 virtual bool can_call_java() const { return true; }
523
524 virtual bool is_active_Java_thread() const;
525
526 // Thread oop. threadObj() can be null for initial JavaThread
527 // (or for threads attached via JNI)
528 oop threadObj() const;
529 void set_threadOopHandles(oop p);
530 oop vthread() const;
531 void set_vthread(oop p);
532 oop scopedValueCache() const;
533 void set_scopedValueCache(oop p);
534 void clear_scopedValueBindings();
535 oop jvmti_vthread() const;
536 void set_jvmti_vthread(oop p);
537 oop vthread_or_thread() const;
538
539 // Prepare thread and add to priority queue. If a priority is
540 // not specified, use the priority of the thread object. Threads_lock
541 // must be held while this function is called.
542 void prepare(jobject jni_thread, ThreadPriority prio=NoPriority);
543
544 void set_saved_exception_pc(address pc) { _saved_exception_pc = pc; }
545 address saved_exception_pc() { return _saved_exception_pc; }
546
547 ThreadFunction entry_point() const { return _entry_point; }
548
549 // Allocates a new Java level thread object for this thread. thread_name may be null.
550 void allocate_threadObj(Handle thread_group, const char* thread_name, bool daemon, TRAPS);
551
552 // Last frame anchor routines
553
554 JavaFrameAnchor* frame_anchor(void) { return &_anchor; }
555
556 // last_Java_sp
557 bool has_last_Java_frame() const { return _anchor.has_last_Java_frame(); }
558 intptr_t* last_Java_sp() const { return _anchor.last_Java_sp(); }
559
560 // last_Java_pc
561
562 address last_Java_pc(void) { return _anchor.last_Java_pc(); }
563
564 // Safepoint support
565 inline JavaThreadState thread_state() const;
566 inline void set_thread_state(JavaThreadState s);
567 inline void set_thread_state_fence(JavaThreadState s); // fence after setting thread state
568 inline ThreadSafepointState* safepoint_state() const;
569 inline void set_safepoint_state(ThreadSafepointState* state);
570 inline bool is_at_poll_safepoint();
571
572 // JavaThread termination and lifecycle support:
573 void smr_delete();
574 bool on_thread_list() const { return _on_thread_list; }
575 void set_on_thread_list() { _on_thread_list = true; }
576
577 // thread has called JavaThread::exit(), thread's GC barrier is detached
578 // or thread is terminated
579 bool is_exiting() const;
580 // thread's GC barrier is NOT detached and thread is NOT terminated
581 bool is_oop_safe() const;
582 // thread is terminated (no longer on the threads list); the thread must
583 // be protected by a ThreadsListHandle to avoid potential crashes.
584 bool check_is_terminated(TerminatedTypes l_terminated) const {
585 return l_terminated == _thread_terminated || l_terminated == _vm_exited;
586 }
587 bool is_terminated() const;
588 void set_terminated(TerminatedTypes t);
589
590 void block_if_vm_exited();
591
592 bool doing_unsafe_access() { return _doing_unsafe_access; }
593 void set_doing_unsafe_access(bool val) { _doing_unsafe_access = val; }
594
595 bool do_not_unlock_if_synchronized() { return _do_not_unlock_if_synchronized; }
596 void set_do_not_unlock_if_synchronized(bool val) { _do_not_unlock_if_synchronized = val; }
597
598 SafepointMechanism::ThreadData* poll_data() { return &_poll_data; }
599
600 static ByteSize polling_word_offset() {
601 ByteSize offset = byte_offset_of(Thread, _poll_data) +
602 byte_offset_of(SafepointMechanism::ThreadData, _polling_word);
603 // At least on x86_64, safepoint polls encode the offset as disp8 imm.
604 assert(in_bytes(offset) < 128, "Offset >= 128");
605 return offset;
606 }
607
608 static ByteSize polling_page_offset() {
609 ByteSize offset = byte_offset_of(Thread, _poll_data) +
610 byte_offset_of(SafepointMechanism::ThreadData, _polling_page);
611 // At least on x86_64, safepoint polls encode the offset as disp8 imm.
612 assert(in_bytes(offset) < 128, "Offset >= 128");
613 return offset;
614 }
615
616 void set_requires_cross_modify_fence(bool val) PRODUCT_RETURN NOT_PRODUCT({ _requires_cross_modify_fence = val; })
617
618 // Continuation support
619 ContinuationEntry* last_continuation() const { return _cont_entry; }
620 void set_cont_fastpath(intptr_t* x) { _cont_fastpath = x; }
621 void push_cont_fastpath(intptr_t* sp) { if (sp > _cont_fastpath) _cont_fastpath = sp; }
622 void set_cont_fastpath_thread_state(bool x) { _cont_fastpath_thread_state = (int)x; }
623 intptr_t* raw_cont_fastpath() const { return _cont_fastpath; }
624 bool cont_fastpath() const { return _cont_fastpath == nullptr && _cont_fastpath_thread_state != 0; }
625 bool cont_fastpath_thread_state() const { return _cont_fastpath_thread_state != 0; }
626
627 void inc_held_monitor_count(intx i = 1, bool jni = false);
628 void dec_held_monitor_count(intx i = 1, bool jni = false);
629
630 intx held_monitor_count() { return _held_monitor_count; }
631 intx jni_monitor_count() { return _jni_monitor_count; }
632 void clear_jni_monitor_count() { _jni_monitor_count = 0; }
633
634 // Support for SharedRuntime::monitor_exit_helper()
635 ObjectMonitor* unlocked_inflated_monitor() const { return _unlocked_inflated_monitor; }
636 void clear_unlocked_inflated_monitor() {
637 _unlocked_inflated_monitor = nullptr;
638 }
639
640 inline bool is_vthread_mounted() const;
641 inline const ContinuationEntry* vthread_continuation() const;
642
643 private:
644 DEBUG_ONLY(void verify_frame_info();)
645
646 // Support for thread handshake operations
647 HandshakeState _handshake;
648 public:
649 HandshakeState* handshake_state() { return &_handshake; }
650
651 // A JavaThread can always safely operate on it self and other threads
652 // can do it safely if they are the active handshaker.
653 bool is_handshake_safe_for(Thread* th) const {
654 return _handshake.active_handshaker() == th || this == th;
655 }
656
657 // Suspend/resume support for JavaThread
658 // higher-level suspension/resume logic called by the public APIs
659 bool java_suspend();
660 bool java_resume();
661 bool is_suspended() { return _handshake.is_suspended(); }
662
663 // Check for async exception in addition to safepoint.
664 static void check_special_condition_for_native_trans(JavaThread *thread);
665
666 // Synchronize with another thread that is deoptimizing objects of the
667 // current thread, i.e. reverts optimizations based on escape analysis.
668 void wait_for_object_deoptimization();
669
670 #if INCLUDE_JVMTI
671 inline void set_carrier_thread_suspended();
672 inline void clear_carrier_thread_suspended();
673
674 bool is_carrier_thread_suspended() const {
675 return _carrier_thread_suspended;
676 }
677
678 bool is_in_VTMS_transition() const { return _is_in_VTMS_transition; }
679 bool is_in_tmp_VTMS_transition() const { return _is_in_tmp_VTMS_transition; }
680 bool is_in_any_VTMS_transition() const { return _is_in_VTMS_transition || _is_in_tmp_VTMS_transition; }
681
682 void set_is_in_VTMS_transition(bool val);
683 void toggle_is_in_tmp_VTMS_transition() { _is_in_tmp_VTMS_transition = !_is_in_tmp_VTMS_transition; };
684
685 bool is_disable_suspend() const { return _is_disable_suspend; }
686 void toggle_is_disable_suspend() { _is_disable_suspend = !_is_disable_suspend; };
687
688 bool VTMS_transition_mark() const { return Atomic::load(&_VTMS_transition_mark); }
689 void set_VTMS_transition_mark(bool val) { Atomic::store(&_VTMS_transition_mark, val); }
690
691 #ifdef ASSERT
692 bool is_VTMS_transition_disabler() const { return _is_VTMS_transition_disabler; }
693 void set_is_VTMS_transition_disabler(bool val);
694 #endif
695 #endif
696
697 // Support for object deoptimization and JFR suspension
698 void handle_special_runtime_exit_condition();
699 bool has_special_runtime_exit_condition() {
700 return (_suspend_flags & (_obj_deopt JFR_ONLY(| _trace_flag))) != 0;
701 }
702
703 // Stack-locking support (not for LM_LIGHTWEIGHT)
704 bool is_lock_owned(address adr) const;
705
706 // Accessors for vframe array top
707 // The linked list of vframe arrays are sorted on sp. This means when we
708 // unpack the head must contain the vframe array to unpack.
709 void set_vframe_array_head(vframeArray* value) { _vframe_array_head = value; }
710 vframeArray* vframe_array_head() const { return _vframe_array_head; }
711
712 // Side structure for deferring update of java frame locals until deopt occurs
713 JvmtiDeferredUpdates* deferred_updates() const { return _jvmti_deferred_updates; }
714 void set_deferred_updates(JvmtiDeferredUpdates* du) { _jvmti_deferred_updates = du; }
715
716 // These only really exist to make debugging deopt problems simpler
717
718 void set_vframe_array_last(vframeArray* value) { _vframe_array_last = value; }
719 vframeArray* vframe_array_last() const { return _vframe_array_last; }
720
721 // The special resourceMark used during deoptimization
722
723 void set_deopt_mark(DeoptResourceMark* value) { _deopt_mark = value; }
724 DeoptResourceMark* deopt_mark(void) { return _deopt_mark; }
725
726 void set_deopt_compiled_method(nmethod* nm) { _deopt_nmethod = nm; }
727 nmethod* deopt_compiled_method() { return _deopt_nmethod; }
728
729 Method* callee_target() const { return _callee_target; }
730 void set_callee_target (Method* x) { _callee_target = x; }
731
732 // Oop results of vm runtime calls
733 oop vm_result() const { return _vm_result; }
734 void set_vm_result (oop x) { _vm_result = x; }
735
736 void set_vm_result_2 (Metadata* x) { _vm_result_2 = x; }
737
738 oop return_buffered_value() const { return _return_buffered_value; }
739 void set_return_buffered_value(oop val) { _return_buffered_value = val; }
740
741 MemRegion deferred_card_mark() const { return _deferred_card_mark; }
742 void set_deferred_card_mark(MemRegion mr) { _deferred_card_mark = mr; }
743
744 // Is thread in scope of an InternalOOMEMark?
745 bool is_in_internal_oome_mark() const { return _is_in_internal_oome_mark; }
746 void set_is_in_internal_oome_mark(bool b) { _is_in_internal_oome_mark = b; }
747
748 #if INCLUDE_JVMCI
749 jlong pending_failed_speculation() const { return _pending_failed_speculation; }
750 void set_pending_monitorenter(bool b) { _pending_monitorenter = b; }
751 void set_pending_deoptimization(int reason) { _pending_deoptimization = reason; }
752 void set_pending_failed_speculation(jlong failed_speculation) { _pending_failed_speculation = failed_speculation; }
753 void set_pending_transfer_to_interpreter(bool b) { _pending_transfer_to_interpreter = b; }
754 void set_jvmci_alternate_call_target(address a) { assert(_jvmci._alternate_call_target == nullptr, "must be"); _jvmci._alternate_call_target = a; }
755 void set_jvmci_implicit_exception_pc(address a) { assert(_jvmci._implicit_exception_pc == nullptr, "must be"); _jvmci._implicit_exception_pc = a; }
756
757 JVMCIRuntime* libjvmci_runtime() const { return _libjvmci_runtime; }
758 void set_libjvmci_runtime(JVMCIRuntime* rt) {
759 assert((_libjvmci_runtime == nullptr && rt != nullptr) || (_libjvmci_runtime != nullptr && rt == nullptr), "must be");
760 _libjvmci_runtime = rt;
761 }
762 #endif // INCLUDE_JVMCI
763
764 // Exception handling for compiled methods
765 oop exception_oop() const;
766 address exception_pc() const { return _exception_pc; }
767
768 void set_exception_oop(oop o);
769 void set_exception_pc(address a) { _exception_pc = a; }
770 void set_exception_handler_pc(address a) { _exception_handler_pc = a; }
771 void set_is_method_handle_return(bool value) { _is_method_handle_return = value ? 1 : 0; }
772
773 void clear_exception_oop_and_pc() {
774 set_exception_oop(nullptr);
775 set_exception_pc(nullptr);
776 }
777
778 // Check if address is in the usable part of the stack (excludes protected
779 // guard pages). Can be applied to any thread and is an approximation for
780 // using is_in_live_stack when the query has to happen from another thread.
781 bool is_in_usable_stack(address adr) const {
782 return is_in_stack_range_incl(adr, _stack_overflow_state.stack_reserved_zone_base());
783 }
784
785 // Misc. accessors/mutators
786 static ByteSize scopedValueCache_offset() { return byte_offset_of(JavaThread, _scopedValueCache); }
787
788 // For assembly stub generation
789 static ByteSize threadObj_offset() { return byte_offset_of(JavaThread, _threadObj); }
790 static ByteSize vthread_offset() { return byte_offset_of(JavaThread, _vthread); }
791 static ByteSize jni_environment_offset() { return byte_offset_of(JavaThread, _jni_environment); }
792 static ByteSize pending_jni_exception_check_fn_offset() {
793 return byte_offset_of(JavaThread, _pending_jni_exception_check_fn);
794 }
795 static ByteSize last_Java_sp_offset() {
796 return byte_offset_of(JavaThread, _anchor) + JavaFrameAnchor::last_Java_sp_offset();
797 }
798 static ByteSize last_Java_pc_offset() {
799 return byte_offset_of(JavaThread, _anchor) + JavaFrameAnchor::last_Java_pc_offset();
800 }
801 static ByteSize frame_anchor_offset() {
802 return byte_offset_of(JavaThread, _anchor);
803 }
804 static ByteSize callee_target_offset() { return byte_offset_of(JavaThread, _callee_target); }
805 static ByteSize vm_result_offset() { return byte_offset_of(JavaThread, _vm_result); }
806 static ByteSize vm_result_2_offset() { return byte_offset_of(JavaThread, _vm_result_2); }
807 static ByteSize return_buffered_value_offset() { return byte_offset_of(JavaThread, _return_buffered_value); }
808 static ByteSize thread_state_offset() { return byte_offset_of(JavaThread, _thread_state); }
809 static ByteSize saved_exception_pc_offset() { return byte_offset_of(JavaThread, _saved_exception_pc); }
810 static ByteSize osthread_offset() { return byte_offset_of(JavaThread, _osthread); }
811 #if INCLUDE_JVMCI
812 static ByteSize pending_deoptimization_offset() { return byte_offset_of(JavaThread, _pending_deoptimization); }
813 static ByteSize pending_monitorenter_offset() { return byte_offset_of(JavaThread, _pending_monitorenter); }
814 static ByteSize jvmci_alternate_call_target_offset() { return byte_offset_of(JavaThread, _jvmci._alternate_call_target); }
815 static ByteSize jvmci_implicit_exception_pc_offset() { return byte_offset_of(JavaThread, _jvmci._implicit_exception_pc); }
816 static ByteSize jvmci_counters_offset() { return byte_offset_of(JavaThread, _jvmci_counters); }
817 #endif // INCLUDE_JVMCI
818 static ByteSize exception_oop_offset() { return byte_offset_of(JavaThread, _exception_oop); }
819 static ByteSize exception_pc_offset() { return byte_offset_of(JavaThread, _exception_pc); }
820 static ByteSize exception_handler_pc_offset() { return byte_offset_of(JavaThread, _exception_handler_pc); }
821 static ByteSize is_method_handle_return_offset() { return byte_offset_of(JavaThread, _is_method_handle_return); }
822
823 static ByteSize active_handles_offset() { return byte_offset_of(JavaThread, _active_handles); }
824
825 // StackOverflow offsets
826 static ByteSize stack_overflow_limit_offset() {
827 return byte_offset_of(JavaThread, _stack_overflow_state._stack_overflow_limit);
828 }
829 static ByteSize stack_guard_state_offset() {
830 return byte_offset_of(JavaThread, _stack_overflow_state._stack_guard_state);
831 }
832 static ByteSize reserved_stack_activation_offset() {
833 return byte_offset_of(JavaThread, _stack_overflow_state._reserved_stack_activation);
834 }
835 static ByteSize shadow_zone_safe_limit() {
836 return byte_offset_of(JavaThread, _stack_overflow_state._shadow_zone_safe_limit);
837 }
838 static ByteSize shadow_zone_growth_watermark() {
839 return byte_offset_of(JavaThread, _stack_overflow_state._shadow_zone_growth_watermark);
840 }
841
842 static ByteSize suspend_flags_offset() { return byte_offset_of(JavaThread, _suspend_flags); }
843
844 static ByteSize do_not_unlock_if_synchronized_offset() { return byte_offset_of(JavaThread, _do_not_unlock_if_synchronized); }
845 static ByteSize should_post_on_exceptions_flag_offset() {
846 return byte_offset_of(JavaThread, _should_post_on_exceptions_flag);
847 }
848 static ByteSize doing_unsafe_access_offset() { return byte_offset_of(JavaThread, _doing_unsafe_access); }
849 NOT_PRODUCT(static ByteSize requires_cross_modify_fence_offset() { return byte_offset_of(JavaThread, _requires_cross_modify_fence); })
850
851 static ByteSize cont_entry_offset() { return byte_offset_of(JavaThread, _cont_entry); }
852 static ByteSize cont_fastpath_offset() { return byte_offset_of(JavaThread, _cont_fastpath); }
853 static ByteSize held_monitor_count_offset() { return byte_offset_of(JavaThread, _held_monitor_count); }
854 static ByteSize jni_monitor_count_offset() { return byte_offset_of(JavaThread, _jni_monitor_count); }
855 static ByteSize unlocked_inflated_monitor_offset() { return byte_offset_of(JavaThread, _unlocked_inflated_monitor); }
856
857 #if INCLUDE_JVMTI
858 static ByteSize is_in_VTMS_transition_offset() { return byte_offset_of(JavaThread, _is_in_VTMS_transition); }
859 static ByteSize is_in_tmp_VTMS_transition_offset() { return byte_offset_of(JavaThread, _is_in_tmp_VTMS_transition); }
860 static ByteSize is_disable_suspend_offset() { return byte_offset_of(JavaThread, _is_disable_suspend); }
861 #endif
862
863 // Returns the jni environment for this thread
864 JNIEnv* jni_environment() { return &_jni_environment; }
865
866 // Returns the current thread as indicated by the given JNIEnv.
867 // We don't assert it is Thread::current here as that is done at the
868 // external JNI entry points where the JNIEnv is passed into the VM.
869 static JavaThread* thread_from_jni_environment(JNIEnv* env) {
870 JavaThread* current = reinterpret_cast<JavaThread*>(((intptr_t)env - in_bytes(jni_environment_offset())));
871 // We can't normally get here in a thread that has completed its
872 // execution and so "is_terminated", except when the call is from
873 // AsyncGetCallTrace, which can be triggered by a signal at any point in
874 // a thread's lifecycle. A thread is also considered terminated if the VM
875 // has exited, so we have to check this and block in case this is a daemon
876 // thread returning to the VM (the JNI DirectBuffer entry points rely on
877 // this).
878 if (current->is_terminated()) {
879 current->block_if_vm_exited();
880 }
881 return current;
882 }
883
884 // JNI critical regions. These can nest.
885 bool in_critical() { return _jni_active_critical > 0; }
886 bool in_last_critical() { return _jni_active_critical == 1; }
887 inline void enter_critical();
888 void exit_critical() {
889 assert(Thread::current() == this, "this must be current thread");
890 _jni_active_critical--;
891 assert(_jni_active_critical >= 0, "JNI critical nesting problem?");
892 }
893
894 // Checked JNI: is the programmer required to check for exceptions, if so specify
895 // which function name. Returning to a Java frame should implicitly clear the
896 // pending check, this is done for Native->Java transitions (i.e. user JNI code).
897 // VM->Java transitions are not cleared, it is expected that JNI code enclosed
898 // within ThreadToNativeFromVM makes proper exception checks (i.e. VM internal).
899 bool is_pending_jni_exception_check() const { return _pending_jni_exception_check_fn != nullptr; }
900 void clear_pending_jni_exception_check() { _pending_jni_exception_check_fn = nullptr; }
901 const char* get_pending_jni_exception_check() const { return _pending_jni_exception_check_fn; }
902 void set_pending_jni_exception_check(const char* fn_name) { _pending_jni_exception_check_fn = (char*) fn_name; }
903
904 // For deadlock detection
905 int depth_first_number() { return _depth_first_number; }
906 void set_depth_first_number(int dfn) { _depth_first_number = dfn; }
907
908 public:
909 bool in_deopt_handler() const { return _in_deopt_handler > 0; }
910 void inc_in_deopt_handler() { _in_deopt_handler++; }
911 void dec_in_deopt_handler() {
912 assert(_in_deopt_handler > 0, "mismatched deopt nesting");
913 if (_in_deopt_handler > 0) { // robustness
914 _in_deopt_handler--;
915 }
916 }
917
918 private:
919 void set_entry_point(ThreadFunction entry_point) { _entry_point = entry_point; }
920
921 // factor out low-level mechanics for use in both normal and error cases
922 const char* get_thread_name_string(char* buf = nullptr, int buflen = 0) const;
923
924 public:
925
926 // Frame iteration; calls the function f for all frames on the stack
927 void frames_do(void f(frame*, const RegisterMap*));
928
929 // Memory operations
930 void oops_do_frames(OopClosure* f, NMethodClosure* cf);
931 void oops_do_no_frames(OopClosure* f, NMethodClosure* cf);
932
933 // GC operations
934 virtual void nmethods_do(NMethodClosure* cf);
935
936 // RedefineClasses Support
937 void metadata_do(MetadataClosure* f);
938
939 // Debug method asserting thread states are correct during a handshake operation.
940 DEBUG_ONLY(void verify_states_for_handshake();)
941
942 // Misc. operations
943 const char* name() const;
944 const char* name_raw() const;
945 const char* type_name() const { return "JavaThread"; }
946 static const char* name_for(oop thread_obj);
947
948 void print_on(outputStream* st, bool print_extended_info) const;
949 void print_on(outputStream* st) const { print_on(st, false); }
950 void print() const;
951 void print_thread_state_on(outputStream*) const;
952 void print_on_error(outputStream* st, char* buf, int buflen) const;
953 void print_name_on_error(outputStream* st, char* buf, int buflen) const;
954 void verify();
955
956 // Accessing frames
957 frame last_frame() {
958 _anchor.make_walkable();
959 return pd_last_frame();
960 }
961 javaVFrame* last_java_vframe(RegisterMap* reg_map) { return last_java_vframe(last_frame(), reg_map); }
962
963 frame carrier_last_frame(RegisterMap* reg_map);
964 javaVFrame* carrier_last_java_vframe(RegisterMap* reg_map) { return last_java_vframe(carrier_last_frame(reg_map), reg_map); }
965
966 frame vthread_last_frame();
967 javaVFrame* vthread_last_java_vframe(RegisterMap* reg_map) { return last_java_vframe(vthread_last_frame(), reg_map); }
968
969 frame platform_thread_last_frame(RegisterMap* reg_map);
970 javaVFrame* platform_thread_last_java_vframe(RegisterMap* reg_map) {
971 return last_java_vframe(platform_thread_last_frame(reg_map), reg_map);
972 }
973
974 javaVFrame* last_java_vframe(const frame f, RegisterMap* reg_map);
975
976 // Returns method at 'depth' java or native frames down the stack
977 // Used for security checks
978 Klass* security_get_caller_class(int depth);
979
980 // Print stack trace in external format
981 // These variants print carrier/platform thread information only.
982 void print_stack_on(outputStream* st);
983 void print_stack() { print_stack_on(tty); }
984 // This prints the currently mounted virtual thread.
985 void print_vthread_stack_on(outputStream* st);
986 // This prints the active stack: either carrier/platform or virtual.
987 void print_active_stack_on(outputStream* st);
988 // Print current stack trace for checked JNI warnings and JNI fatal errors.
989 // This is the external format from above, but selecting the platform
990 // or vthread as applicable.
991 void print_jni_stack();
992
993 // Print stack traces in various internal formats
994 void trace_stack() PRODUCT_RETURN;
995 void trace_stack_from(vframe* start_vf) PRODUCT_RETURN;
996 void trace_frames() PRODUCT_RETURN;
997
998 // Print an annotated view of the stack frames
999 void print_frame_layout(int depth = 0, bool validate_only = false) NOT_DEBUG_RETURN;
1000 void validate_frame_layout() {
1001 print_frame_layout(0, true);
1002 }
1003
1004 // Function for testing deoptimization
1005 void deoptimize();
1006 void make_zombies();
1007
1008 void deoptimize_marked_methods();
1009
1010 public:
1011 // Returns the running thread as a JavaThread
1012 static JavaThread* current() {
1013 return JavaThread::cast(Thread::current());
1014 }
1015
1016 // Returns the current thread as a JavaThread, or nullptr if not attached
1017 static inline JavaThread* current_or_null();
1018
1019 // Casts
1020 static JavaThread* cast(Thread* t) {
1021 assert(t->is_Java_thread(), "incorrect cast to JavaThread");
1022 return static_cast<JavaThread*>(t);
1023 }
1024
1025 static const JavaThread* cast(const Thread* t) {
1026 assert(t->is_Java_thread(), "incorrect cast to const JavaThread");
1027 return static_cast<const JavaThread*>(t);
1028 }
1029
1030 // Returns the active Java thread. Do not use this if you know you are calling
1031 // from a JavaThread, as it's slower than JavaThread::current. If called from
1032 // the VMThread, it also returns the JavaThread that instigated the VMThread's
1033 // operation. You may not want that either.
1034 static JavaThread* active();
1035
1036 protected:
1037 virtual void pre_run();
1038 virtual void run();
1039 void thread_main_inner();
1040 virtual void post_run();
1041
1042 public:
1043 // Thread local information maintained by JVMTI.
1044 void set_jvmti_thread_state(JvmtiThreadState *value) { _jvmti_thread_state = value; }
1045 // A JvmtiThreadState is lazily allocated. This jvmti_thread_state()
1046 // getter is used to get this JavaThread's JvmtiThreadState if it has
1047 // one which means null can be returned. JvmtiThreadState::state_for()
1048 // is used to get the specified JavaThread's JvmtiThreadState if it has
1049 // one or it allocates a new JvmtiThreadState for the JavaThread and
1050 // returns it. JvmtiThreadState::state_for() will return null only if
1051 // the specified JavaThread is exiting.
1052 JvmtiThreadState *jvmti_thread_state() const { return _jvmti_thread_state; }
1053 static ByteSize jvmti_thread_state_offset() { return byte_offset_of(JavaThread, _jvmti_thread_state); }
1054
1055 #if INCLUDE_JVMTI
1056 // Rebind JVMTI thread state from carrier to virtual or from virtual to carrier.
1057 JvmtiThreadState *rebind_to_jvmti_thread_state_of(oop thread_oop);
1058 #endif
1059
1060 // JVMTI PopFrame support
1061 // Setting and clearing popframe_condition
1062 // All of these enumerated values are bits. popframe_pending
1063 // indicates that a PopFrame() has been requested and not yet been
1064 // completed. popframe_processing indicates that that PopFrame() is in
1065 // the process of being completed. popframe_force_deopt_reexecution_bit
1066 // indicates that special handling is required when returning to a
1067 // deoptimized caller.
1068 enum PopCondition {
1069 popframe_inactive = 0x00,
1070 popframe_pending_bit = 0x01,
1071 popframe_processing_bit = 0x02,
1072 popframe_force_deopt_reexecution_bit = 0x04
1073 };
1074 PopCondition popframe_condition() { return (PopCondition) _popframe_condition; }
1075 void set_popframe_condition(PopCondition c) { _popframe_condition = c; }
1076 void set_popframe_condition_bit(PopCondition c) { _popframe_condition |= c; }
1077 void clear_popframe_condition() { _popframe_condition = popframe_inactive; }
1078 static ByteSize popframe_condition_offset() { return byte_offset_of(JavaThread, _popframe_condition); }
1079 bool has_pending_popframe() { return (popframe_condition() & popframe_pending_bit) != 0; }
1080 bool popframe_forcing_deopt_reexecution() { return (popframe_condition() & popframe_force_deopt_reexecution_bit) != 0; }
1081
1082 bool pop_frame_in_process(void) { return ((_popframe_condition & popframe_processing_bit) != 0); }
1083 void set_pop_frame_in_process(void) { _popframe_condition |= popframe_processing_bit; }
1084 void clr_pop_frame_in_process(void) { _popframe_condition &= ~popframe_processing_bit; }
1085
1086 int frames_to_pop_failed_realloc() const { return _frames_to_pop_failed_realloc; }
1087 void set_frames_to_pop_failed_realloc(int nb) { _frames_to_pop_failed_realloc = nb; }
1088 void dec_frames_to_pop_failed_realloc() { _frames_to_pop_failed_realloc--; }
1089
1090 private:
1091 // Saved incoming arguments to popped frame.
1092 // Used only when popped interpreted frame returns to deoptimized frame.
1093 void* _popframe_preserved_args;
1094 int _popframe_preserved_args_size;
1095
1096 public:
1097 void popframe_preserve_args(ByteSize size_in_bytes, void* start);
1098 void* popframe_preserved_args();
1099 ByteSize popframe_preserved_args_size();
1100 WordSize popframe_preserved_args_size_in_words();
1101 void popframe_free_preserved_args();
1102
1103
1104 private:
1105 JvmtiThreadState *_jvmti_thread_state;
1106
1107 // Used by the interpreter in fullspeed mode for frame pop, method
1108 // entry, method exit and single stepping support. This field is
1109 // only set to non-zero at a safepoint or using a direct handshake
1110 // (see EnterInterpOnlyModeClosure).
1111 // It can be set to zero asynchronously to this threads execution (i.e., without
1112 // safepoint/handshake or a lock) so we have to be very careful.
1113 // Accesses by other threads are synchronized using JvmtiThreadState_lock though.
1114 int _interp_only_mode;
1115
1116 public:
1117 // used by the interpreter for fullspeed debugging support (see above)
1118 static ByteSize interp_only_mode_offset() { return byte_offset_of(JavaThread, _interp_only_mode); }
1119 bool is_interp_only_mode() { return (_interp_only_mode != 0); }
1120 int get_interp_only_mode() { return _interp_only_mode; }
1121 int set_interp_only_mode(int val) { return _interp_only_mode = val; }
1122 void increment_interp_only_mode() { ++_interp_only_mode; }
1123 void decrement_interp_only_mode() { --_interp_only_mode; }
1124
1125 // support for cached flag that indicates whether exceptions need to be posted for this thread
1126 // if this is false, we can avoid deoptimizing when events are thrown
1127 // this gets set to reflect whether jvmtiExport::post_exception_throw would actually do anything
1128 private:
1129 int _should_post_on_exceptions_flag;
1130
1131 public:
1132 void set_should_post_on_exceptions_flag(int val) { _should_post_on_exceptions_flag = val; }
1133
1134 private:
1135 ThreadStatistics *_thread_stat;
1136
1137 public:
1138 ThreadStatistics* get_thread_stat() const { return _thread_stat; }
1139
1140 // Return a blocker object for which this thread is blocked parking.
1141 oop current_park_blocker();
1142
1143 private:
1144 static size_t _stack_size_at_create;
1145
1146 public:
1147 static inline size_t stack_size_at_create(void) {
1148 return _stack_size_at_create;
1149 }
1150 static inline void set_stack_size_at_create(size_t value) {
1151 _stack_size_at_create = value;
1152 }
1153
1154 // Machine dependent stuff
1155 #include OS_CPU_HEADER(javaThread)
1156
1157 // JSR166 per-thread parker
1158 private:
1159 Parker _parker;
1160 public:
1161 Parker* parker() { return &_parker; }
1162
1163 public:
1164 // clearing/querying jni attach status
1165 bool is_attaching_via_jni() const { return _jni_attach_state == _attaching_via_jni; }
1166 bool has_attached_via_jni() const { return is_attaching_via_jni() || _jni_attach_state == _attached_via_jni; }
1167 inline void set_done_attaching_via_jni();
1168
1169 // Stack dump assistance:
1170 // Track the class we want to initialize but for which we have to wait
1171 // on its init_lock() because it is already being initialized.
1172 void set_class_to_be_initialized(InstanceKlass* k);
1173 InstanceKlass* class_to_be_initialized() const;
1174
1175 private:
1176 InstanceKlass* _class_to_be_initialized;
1177
1178 // java.lang.Thread.sleep support
1179 ParkEvent * _SleepEvent;
1180 public:
1181 bool sleep(jlong millis);
1182 bool sleep_nanos(jlong nanos);
1183
1184 // java.lang.Thread interruption support
1185 void interrupt();
1186 bool is_interrupted(bool clear_interrupted);
1187
1188 // This is only for use by JVMTI RawMonitorWait. It emulates the actions of
1189 // the Java code in Object::wait which are not present in RawMonitorWait.
1190 bool get_and_clear_interrupted();
1191
1192 private:
1193 LockStack _lock_stack;
1194 OMCache _om_cache;
1195
1196 public:
1197 LockStack& lock_stack() { return _lock_stack; }
1198
1199 static ByteSize lock_stack_offset() { return byte_offset_of(JavaThread, _lock_stack); }
1200 // Those offsets are used in code generators to access the LockStack that is embedded in this
1201 // JavaThread structure. Those accesses are relative to the current thread, which
1202 // is typically in a dedicated register.
1203 static ByteSize lock_stack_top_offset() { return lock_stack_offset() + LockStack::top_offset(); }
1204 static ByteSize lock_stack_base_offset() { return lock_stack_offset() + LockStack::base_offset(); }
1205
1206 static ByteSize om_cache_offset() { return byte_offset_of(JavaThread, _om_cache); }
1207 static ByteSize om_cache_oops_offset() { return om_cache_offset() + OMCache::entries_offset(); }
1208
1209 void om_set_monitor_cache(ObjectMonitor* monitor);
1210 void om_clear_monitor_cache();
1211 ObjectMonitor* om_get_from_monitor_cache(oop obj);
1212
1213 static OopStorage* thread_oop_storage();
1214
1215 static void verify_cross_modify_fence_failure(JavaThread *thread) PRODUCT_RETURN;
1216
1217 // Helper function to create the java.lang.Thread object for a
1218 // VM-internal thread. The thread will have the given name and be
1219 // part of the System ThreadGroup.
1220 static Handle create_system_thread_object(const char* name, TRAPS);
1221
1222 // Helper function to start a VM-internal daemon thread.
1223 // E.g. ServiceThread, NotificationThread, CompilerThread etc.
1224 static void start_internal_daemon(JavaThread* current, JavaThread* target,
1225 Handle thread_oop, ThreadPriority prio);
1226
1227 // Helper function to do vm_exit_on_initialization for osthread
1228 // resource allocation failure.
1229 static void vm_exit_on_osthread_failure(JavaThread* thread);
1230
1231 // Deferred OopHandle release support
1232 private:
1233 // List of OopHandles to be released - guarded by the Service_lock.
1234 static OopHandleList* _oop_handle_list;
1235 // Add our OopHandles to the list for the service thread to release.
1236 void add_oop_handles_for_release();
1237 // Called by the ServiceThread to release the OopHandles.
1238 static void release_oop_handles();
1239 // Called by the ServiceThread to poll if there are any OopHandles to release.
1240 // Called when holding the Service_lock.
1241 static bool has_oop_handles_to_release() {
1242 return _oop_handle_list != nullptr;
1243 }
1244 };
1245
1246 inline JavaThread* JavaThread::current_or_null() {
1247 Thread* current = Thread::current_or_null();
1248 return current != nullptr ? JavaThread::cast(current) : nullptr;
1249 }
1250
1251 class UnlockFlagSaver {
1252 private:
1253 JavaThread* _thread;
1254 bool _do_not_unlock;
1255 public:
1256 UnlockFlagSaver(JavaThread* t) {
1257 _thread = t;
1258 _do_not_unlock = t->do_not_unlock_if_synchronized();
1259 t->set_do_not_unlock_if_synchronized(false);
1260 }
1261 ~UnlockFlagSaver() {
1262 _thread->set_do_not_unlock_if_synchronized(_do_not_unlock);
1263 }
1264 };
1265
1266 class JNIHandleMark : public StackObj {
1267 JavaThread* _thread;
1268 public:
1269 JNIHandleMark(JavaThread* thread) : _thread(thread) {
1270 thread->push_jni_handle_block();
1271 }
1272 ~JNIHandleMark() { _thread->pop_jni_handle_block(); }
1273 };
1274
1275 #endif // SHARE_RUNTIME_JAVATHREAD_HPP