1 /*
2 * Copyright (c) 1997, 2021, 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_THREAD_HPP
27 #define SHARE_RUNTIME_THREAD_HPP
28
29 #include "jni.h"
30 #include "gc/shared/gcThreadLocalData.hpp"
31 #include "gc/shared/threadLocalAllocBuffer.hpp"
32 #include "memory/allocation.hpp"
33 #include "oops/oop.hpp"
34 #include "oops/oopHandle.hpp"
35 #include "runtime/frame.hpp"
36 #include "runtime/globals.hpp"
37 #include "runtime/handshake.hpp"
38 #include "runtime/javaFrameAnchor.hpp"
39 #include "runtime/mutexLocker.hpp"
40 #include "runtime/os.hpp"
41 #include "runtime/park.hpp"
42 #include "runtime/safepointMechanism.hpp"
43 #include "runtime/stackWatermarkSet.hpp"
44 #include "runtime/stackOverflow.hpp"
45 #include "runtime/threadHeapSampler.hpp"
46 #include "runtime/threadLocalStorage.hpp"
47 #include "runtime/threadStatisticalInfo.hpp"
48 #include "runtime/unhandledOops.hpp"
49 #include "utilities/align.hpp"
50 #include "utilities/exceptions.hpp"
51 #include "utilities/globalDefinitions.hpp"
52 #include "utilities/macros.hpp"
53 #if INCLUDE_JFR
54 #include "jfr/support/jfrThreadExtension.hpp"
55 #endif
56
57 class SafeThreadsListPtr;
58 class ThreadSafepointState;
59 class ThreadsList;
60 class ThreadsSMRSupport;
61
62 class JNIHandleBlock;
63 class JvmtiRawMonitor;
64 class JvmtiSampledObjectAllocEventCollector;
65 class JvmtiThreadState;
66 class JvmtiVMObjectAllocEventCollector;
67 class OSThread;
68 class ThreadStatistics;
69 class ConcurrentLocksDump;
70 class MonitorInfo;
71
72 class vframeArray;
73 class vframe;
74 class javaVFrame;
75
76 class DeoptResourceMark;
77 class JvmtiDeferredUpdates;
78
79 class ThreadClosure;
80 class ICRefillVerifier;
81
82 class Metadata;
83 class ResourceArea;
84
85 class OopStorage;
86
87 DEBUG_ONLY(class ResourceMark;)
88
89 class WorkerThread;
90
91 class JavaThread;
92
93 // Class hierarchy
94 // - Thread
95 // - JavaThread
96 // - various subclasses eg CompilerThread, ServiceThread
97 // - NonJavaThread
98 // - NamedThread
99 // - VMThread
100 // - ConcurrentGCThread
101 // - WorkerThread
102 // - GangWorker
103 // - WatcherThread
104 // - JfrThreadSampler
105 // - LogAsyncWriter
106 //
107 // All Thread subclasses must be either JavaThread or NonJavaThread.
108 // This means !t->is_Java_thread() iff t is a NonJavaThread, or t is
109 // a partially constructed/destroyed Thread.
110
111 // Thread execution sequence and actions:
112 // All threads:
113 // - thread_native_entry // per-OS native entry point
114 // - stack initialization
115 // - other OS-level initialization (signal masks etc)
116 // - handshake with creating thread (if not started suspended)
117 // - this->call_run() // common shared entry point
118 // - shared common initialization
119 // - this->pre_run() // virtual per-thread-type initialization
120 // - this->run() // virtual per-thread-type "main" logic
121 // - shared common tear-down
122 // - this->post_run() // virtual per-thread-type tear-down
123 // - // 'this' no longer referenceable
124 // - OS-level tear-down (minimal)
125 // - final logging
126 //
127 // For JavaThread:
128 // - this->run() // virtual but not normally overridden
129 // - this->thread_main_inner() // extra call level to ensure correct stack calculations
130 // - this->entry_point() // set differently for each kind of JavaThread
131
132 class Thread: public ThreadShadow {
133 friend class VMStructs;
134 friend class JVMCIVMStructs;
135 private:
136
137 #ifndef USE_LIBRARY_BASED_TLS_ONLY
138 // Current thread is maintained as a thread-local variable
139 static THREAD_LOCAL Thread* _thr_current;
140 #endif
141
142 // Thread local data area available to the GC. The internal
143 // structure and contents of this data area is GC-specific.
144 // Only GC and GC barrier code should access this data area.
145 GCThreadLocalData _gc_data;
146
147 public:
148 static ByteSize gc_data_offset() {
149 return byte_offset_of(Thread, _gc_data);
150 }
151
152 template <typename T> T* gc_data() {
153 STATIC_ASSERT(sizeof(T) <= sizeof(_gc_data));
154 return reinterpret_cast<T*>(&_gc_data);
155 }
156
157 // Exception handling
158 // (Note: _pending_exception and friends are in ThreadShadow)
159 //oop _pending_exception; // pending exception for current thread
160 // const char* _exception_file; // file information for exception (debugging only)
161 // int _exception_line; // line information for exception (debugging only)
162 protected:
163
164 DEBUG_ONLY(static Thread* _starting_thread;)
165
166 // JavaThread lifecycle support:
167 friend class SafeThreadsListPtr; // for _threads_list_ptr, cmpxchg_threads_hazard_ptr(), {dec_,inc_,}nested_threads_hazard_ptr_cnt(), {g,s}et_threads_hazard_ptr(), inc_nested_handle_cnt(), tag_hazard_ptr() access
168 friend class ScanHazardPtrGatherProtectedThreadsClosure; // for cmpxchg_threads_hazard_ptr(), get_threads_hazard_ptr(), is_hazard_ptr_tagged() access
169 friend class ScanHazardPtrGatherThreadsListClosure; // for get_threads_hazard_ptr(), untag_hazard_ptr() access
170 friend class ScanHazardPtrPrintMatchingThreadsClosure; // for get_threads_hazard_ptr(), is_hazard_ptr_tagged() access
171 friend class ThreadsSMRSupport; // for _nested_threads_hazard_ptr_cnt, _threads_hazard_ptr, _threads_list_ptr access
172 friend class ThreadsListHandleTest; // for _nested_threads_hazard_ptr_cnt, _threads_hazard_ptr, _threads_list_ptr access
173 friend class ValidateHazardPtrsClosure; // for get_threads_hazard_ptr(), untag_hazard_ptr() access
174
175 ThreadsList* volatile _threads_hazard_ptr;
176 SafeThreadsListPtr* _threads_list_ptr;
177 ThreadsList* cmpxchg_threads_hazard_ptr(ThreadsList* exchange_value, ThreadsList* compare_value);
178 ThreadsList* get_threads_hazard_ptr() const;
179 void set_threads_hazard_ptr(ThreadsList* new_list);
180 static bool is_hazard_ptr_tagged(ThreadsList* list) {
181 return (intptr_t(list) & intptr_t(1)) == intptr_t(1);
182 }
183 static ThreadsList* tag_hazard_ptr(ThreadsList* list) {
184 return (ThreadsList*)(intptr_t(list) | intptr_t(1));
185 }
186 static ThreadsList* untag_hazard_ptr(ThreadsList* list) {
187 return (ThreadsList*)(intptr_t(list) & ~intptr_t(1));
188 }
189 // This field is enabled via -XX:+EnableThreadSMRStatistics:
190 uint _nested_threads_hazard_ptr_cnt;
191 void dec_nested_threads_hazard_ptr_cnt() {
192 assert(_nested_threads_hazard_ptr_cnt != 0, "mismatched {dec,inc}_nested_threads_hazard_ptr_cnt()");
193 _nested_threads_hazard_ptr_cnt--;
194 }
195 void inc_nested_threads_hazard_ptr_cnt() {
196 _nested_threads_hazard_ptr_cnt++;
197 }
198 uint nested_threads_hazard_ptr_cnt() {
199 return _nested_threads_hazard_ptr_cnt;
200 }
201
202 public:
203 // Is the target JavaThread protected by the calling Thread
204 // or by some other mechanism:
205 static bool is_JavaThread_protected(const JavaThread* p);
206
207 void* operator new(size_t size) throw() { return allocate(size, true); }
208 void* operator new(size_t size, const std::nothrow_t& nothrow_constant) throw() {
209 return allocate(size, false); }
210 void operator delete(void* p);
211
212 protected:
213 static void* allocate(size_t size, bool throw_excpt, MEMFLAGS flags = mtThread);
214
215 private:
216 DEBUG_ONLY(bool _suspendible_thread;)
217
218 public:
219 // Determines if a heap allocation failure will be retried
220 // (e.g., by deoptimizing and re-executing in the interpreter).
221 // In this case, the failed allocation must raise
222 // Universe::out_of_memory_error_retry() and omit side effects
223 // such as JVMTI events and handling -XX:+HeapDumpOnOutOfMemoryError
224 // and -XX:OnOutOfMemoryError.
225 virtual bool in_retryable_allocation() const { return false; }
226
227 #ifdef ASSERT
228 void set_suspendible_thread() {
229 _suspendible_thread = true;
230 }
231
232 void clear_suspendible_thread() {
233 _suspendible_thread = false;
234 }
235
236 bool is_suspendible_thread() { return _suspendible_thread; }
237 #endif
238
239 private:
240 // Active_handles points to a block of handles
241 JNIHandleBlock* _active_handles;
242
243 // One-element thread local free list
244 JNIHandleBlock* _free_handle_block;
245
246 // Point to the last handle mark
247 HandleMark* _last_handle_mark;
248
249 // Claim value for parallel iteration over threads.
250 uintx _threads_do_token;
251
252 // Support for GlobalCounter
253 private:
254 volatile uintx _rcu_counter;
255 public:
256 volatile uintx* get_rcu_counter() {
257 return &_rcu_counter;
258 }
259
260 public:
261 void set_last_handle_mark(HandleMark* mark) { _last_handle_mark = mark; }
262 HandleMark* last_handle_mark() const { return _last_handle_mark; }
263 private:
264
265 #ifdef ASSERT
266 ICRefillVerifier* _missed_ic_stub_refill_verifier;
267
268 public:
269 ICRefillVerifier* missed_ic_stub_refill_verifier() {
270 return _missed_ic_stub_refill_verifier;
271 }
272
273 void set_missed_ic_stub_refill_verifier(ICRefillVerifier* verifier) {
274 _missed_ic_stub_refill_verifier = verifier;
275 }
276 #endif // ASSERT
277
278 private:
279 // Used by SkipGCALot class.
280 NOT_PRODUCT(bool _skip_gcalot;) // Should we elide gc-a-lot?
281
282 friend class GCLocker;
283
284 private:
285 ThreadLocalAllocBuffer _tlab; // Thread-local eden
286 jlong _allocated_bytes; // Cumulative number of bytes allocated on
287 // the Java heap
288 ThreadHeapSampler _heap_sampler; // For use when sampling the memory.
289
290 ThreadStatisticalInfo _statistical_info; // Statistics about the thread
291
292 JFR_ONLY(DEFINE_THREAD_LOCAL_FIELD_JFR;) // Thread-local data for jfr
293
294 JvmtiRawMonitor* _current_pending_raw_monitor; // JvmtiRawMonitor this thread
295 // is waiting to lock
296 public:
297 // Constructor
298 Thread();
299 virtual ~Thread() = 0; // Thread is abstract.
300
301 // Manage Thread::current()
302 void initialize_thread_current();
303 static void clear_thread_current(); // TLS cleanup needed before threads terminate
304
305 protected:
306 // To be implemented by children.
307 virtual void run() = 0;
308 virtual void pre_run() = 0;
309 virtual void post_run() = 0; // Note: Thread must not be deleted prior to calling this!
310
311 #ifdef ASSERT
312 enum RunState {
313 PRE_CALL_RUN,
314 CALL_RUN,
315 PRE_RUN,
316 RUN,
317 POST_RUN
318 // POST_CALL_RUN - can't define this one as 'this' may be deleted when we want to set it
319 };
320 RunState _run_state; // for lifecycle checks
321 #endif
322
323
324 public:
325 // invokes <ChildThreadClass>::run(), with common preparations and cleanups.
326 void call_run();
327
328 // Testers
329 virtual bool is_VM_thread() const { return false; }
330 virtual bool is_Java_thread() const { return false; }
331 virtual bool is_Compiler_thread() const { return false; }
332 virtual bool is_Code_cache_sweeper_thread() const { return false; }
333 virtual bool is_service_thread() const { return false; }
334 virtual bool is_monitor_deflation_thread() const { return false; }
335 virtual bool is_hidden_from_external_view() const { return false; }
336 virtual bool is_jvmti_agent_thread() const { return false; }
337 virtual bool is_Watcher_thread() const { return false; }
338 virtual bool is_ConcurrentGC_thread() const { return false; }
339 virtual bool is_Named_thread() const { return false; }
340 virtual bool is_Worker_thread() const { return false; }
341 virtual bool is_JfrSampler_thread() const { return false; }
342
343 // Can this thread make Java upcalls
344 virtual bool can_call_java() const { return false; }
345
346 // Is this a JavaThread that is on the VM's current ThreadsList?
347 // If so it must participate in the safepoint protocol.
348 virtual bool is_active_Java_thread() const { return false; }
349
350 // All threads are given names. For singleton subclasses we can
351 // just hard-wire the known name of the instance. JavaThreads and
352 // NamedThreads support multiple named instances, and dynamic
353 // changing of the name of an instance.
354 virtual const char* name() const { return "Unknown thread"; }
355
356 // A thread's type name is also made available for debugging
357 // and logging.
358 virtual const char* type_name() const { return "Thread"; }
359
360 // Returns the current thread (ASSERTS if NULL)
361 static inline Thread* current();
362 // Returns the current thread, or NULL if not attached
363 static inline Thread* current_or_null();
364 // Returns the current thread, or NULL if not attached, and is
365 // safe for use from signal-handlers
366 static inline Thread* current_or_null_safe();
367
368 // Common thread operations
369 #ifdef ASSERT
370 static void check_for_dangling_thread_pointer(Thread *thread);
371 #endif
372 static void set_priority(Thread* thread, ThreadPriority priority);
373 static ThreadPriority get_priority(const Thread* const thread);
374 static void start(Thread* thread);
375
376 void set_native_thread_name(const char *name) {
377 assert(Thread::current() == this, "set_native_thread_name can only be called on the current thread");
378 os::set_native_thread_name(name);
379 }
380
381 // Support for Unhandled Oop detection
382 // Add the field for both, fastdebug and debug, builds to keep
383 // Thread's fields layout the same.
384 // Note: CHECK_UNHANDLED_OOPS is defined only for fastdebug build.
385 #ifdef CHECK_UNHANDLED_OOPS
386 private:
387 UnhandledOops* _unhandled_oops;
388 #elif defined(ASSERT)
389 private:
390 void* _unhandled_oops;
391 #endif
392 #ifdef CHECK_UNHANDLED_OOPS
393 public:
394 UnhandledOops* unhandled_oops() { return _unhandled_oops; }
395 // Mark oop safe for gc. It may be stack allocated but won't move.
396 void allow_unhandled_oop(oop *op) {
397 if (CheckUnhandledOops) unhandled_oops()->allow_unhandled_oop(op);
398 }
399 // Clear oops at safepoint so crashes point to unhandled oop violator
400 void clear_unhandled_oops() {
401 if (CheckUnhandledOops) unhandled_oops()->clear_unhandled_oops();
402 }
403 #endif // CHECK_UNHANDLED_OOPS
404
405 public:
406 #ifndef PRODUCT
407 bool skip_gcalot() { return _skip_gcalot; }
408 void set_skip_gcalot(bool v) { _skip_gcalot = v; }
409 #endif
410
411 // Resource area
412 ResourceArea* resource_area() const { return _resource_area; }
413 void set_resource_area(ResourceArea* area) { _resource_area = area; }
414
415 OSThread* osthread() const { return _osthread; }
416 void set_osthread(OSThread* thread) { _osthread = thread; }
417
418 // JNI handle support
419 JNIHandleBlock* active_handles() const { return _active_handles; }
420 void set_active_handles(JNIHandleBlock* block) { _active_handles = block; }
421 JNIHandleBlock* free_handle_block() const { return _free_handle_block; }
422 void set_free_handle_block(JNIHandleBlock* block) { _free_handle_block = block; }
423
424 // Internal handle support
425 HandleArea* handle_area() const { return _handle_area; }
426 void set_handle_area(HandleArea* area) { _handle_area = area; }
427
428 GrowableArray<Metadata*>* metadata_handles() const { return _metadata_handles; }
429 void set_metadata_handles(GrowableArray<Metadata*>* handles){ _metadata_handles = handles; }
430
431 // Thread-Local Allocation Buffer (TLAB) support
432 ThreadLocalAllocBuffer& tlab() { return _tlab; }
433 void initialize_tlab();
434
435 jlong allocated_bytes() { return _allocated_bytes; }
436 void set_allocated_bytes(jlong value) { _allocated_bytes = value; }
437 void incr_allocated_bytes(jlong size) { _allocated_bytes += size; }
438 inline jlong cooked_allocated_bytes();
439
440 ThreadHeapSampler& heap_sampler() { return _heap_sampler; }
441
442 ThreadStatisticalInfo& statistical_info() { return _statistical_info; }
443
444 JFR_ONLY(DEFINE_THREAD_LOCAL_ACCESSOR_JFR;)
445
446 // For tracking the Jvmti raw monitor the thread is pending on.
447 JvmtiRawMonitor* current_pending_raw_monitor() {
448 return _current_pending_raw_monitor;
449 }
450 void set_current_pending_raw_monitor(JvmtiRawMonitor* monitor) {
451 _current_pending_raw_monitor = monitor;
452 }
453
454 // GC support
455 // Apply "f->do_oop" to all root oops in "this".
456 // Used by JavaThread::oops_do.
457 // Apply "cf->do_code_blob" (if !NULL) to all code blobs active in frames
458 virtual void oops_do_no_frames(OopClosure* f, CodeBlobClosure* cf);
459 virtual void oops_do_frames(OopClosure* f, CodeBlobClosure* cf) {}
460 void oops_do(OopClosure* f, CodeBlobClosure* cf);
461
462 // Handles the parallel case for claim_threads_do.
463 private:
464 bool claim_par_threads_do(uintx claim_token);
465 public:
466 // Requires that "claim_token" is that of the current iteration.
467 // If "is_par" is false, sets the token of "this" to
468 // "claim_token", and returns "true". If "is_par" is true,
469 // uses an atomic instruction to set the current thread's token to
470 // "claim_token", if it is not already. Returns "true" iff the
471 // calling thread does the update, this indicates that the calling thread
472 // has claimed the thread in the current iteration.
473 bool claim_threads_do(bool is_par, uintx claim_token) {
474 if (!is_par) {
475 _threads_do_token = claim_token;
476 return true;
477 } else {
478 return claim_par_threads_do(claim_token);
479 }
480 }
481
482 uintx threads_do_token() const { return _threads_do_token; }
483
484 // jvmtiRedefineClasses support
485 void metadata_handles_do(void f(Metadata*));
486
487 private:
488 // Check if address is within the given range of this thread's
489 // stack: stack_base() > adr >/>= limit
490 // The check is inclusive of limit if passed true, else exclusive.
491 bool is_in_stack_range(address adr, address limit, bool inclusive) const {
492 assert(stack_base() > limit && limit >= stack_end(), "limit is outside of stack");
493 return stack_base() > adr && (inclusive ? adr >= limit : adr > limit);
494 }
495
496 public:
497 // Used by fast lock support
498 virtual bool is_lock_owned(address adr) const;
499
500 // Check if address is within the given range of this thread's
501 // stack: stack_base() > adr >= limit
502 bool is_in_stack_range_incl(address adr, address limit) const {
503 return is_in_stack_range(adr, limit, true);
504 }
505
506 // Check if address is within the given range of this thread's
507 // stack: stack_base() > adr > limit
508 bool is_in_stack_range_excl(address adr, address limit) const {
509 return is_in_stack_range(adr, limit, false);
510 }
511
512 // Check if address is in the stack mapped to this thread. Used mainly in
513 // error reporting (so has to include guard zone) and frame printing.
514 // Expects _stack_base to be initialized - checked with assert.
515 bool is_in_full_stack_checked(address adr) const {
516 return is_in_stack_range_incl(adr, stack_end());
517 }
518
519 // Like is_in_full_stack_checked but without the assertions as this
520 // may be called in a thread before _stack_base is initialized.
521 bool is_in_full_stack(address adr) const {
522 address stack_end = _stack_base - _stack_size;
523 return _stack_base > adr && adr >= stack_end;
524 }
525
526 // Check if address is in the live stack of this thread (not just for locks).
527 // Warning: can only be called by the current thread on itself.
528 bool is_in_live_stack(address adr) const {
529 assert(Thread::current() == this, "is_in_live_stack can only be called from current thread");
530 return is_in_stack_range_incl(adr, os::current_stack_pointer());
531 }
532
533 // Sets this thread as starting thread. Returns failure if thread
534 // creation fails due to lack of memory, too many threads etc.
535 bool set_as_starting_thread();
536
537 protected:
538 // OS data associated with the thread
539 OSThread* _osthread; // Platform-specific thread information
540
541 // Thread local resource area for temporary allocation within the VM
542 ResourceArea* _resource_area;
543
544 DEBUG_ONLY(ResourceMark* _current_resource_mark;)
545
546 // Thread local handle area for allocation of handles within the VM
547 HandleArea* _handle_area;
548 GrowableArray<Metadata*>* _metadata_handles;
549
550 // Support for stack overflow handling, get_thread, etc.
551 address _stack_base;
552 size_t _stack_size;
553 int _lgrp_id;
554
555 public:
556 // Stack overflow support
557 address stack_base() const { assert(_stack_base != NULL,"Sanity check"); return _stack_base; }
558 void set_stack_base(address base) { _stack_base = base; }
559 size_t stack_size() const { return _stack_size; }
560 void set_stack_size(size_t size) { _stack_size = size; }
561 address stack_end() const { return stack_base() - stack_size(); }
562 void record_stack_base_and_size();
563 void register_thread_stack_with_NMT() NOT_NMT_RETURN;
564 void unregister_thread_stack_with_NMT() NOT_NMT_RETURN;
565
566 int lgrp_id() const { return _lgrp_id; }
567 void set_lgrp_id(int value) { _lgrp_id = value; }
568
569 // Printing
570 void print_on(outputStream* st, bool print_extended_info) const;
571 virtual void print_on(outputStream* st) const { print_on(st, false); }
572 void print() const;
573 virtual void print_on_error(outputStream* st, char* buf, int buflen) const;
574 // Basic, non-virtual, printing support that is simple and always safe.
575 void print_value_on(outputStream* st) const;
576
577 // Debug-only code
578 #ifdef ASSERT
579 private:
580 // Deadlock detection support for Mutex locks. List of locks own by thread.
581 Mutex* _owned_locks;
582 // Mutex::set_owner_implementation is the only place where _owned_locks is modified,
583 // thus the friendship
584 friend class Mutex;
585 friend class Monitor;
586
587 public:
588 void print_owned_locks_on(outputStream* st) const;
589 void print_owned_locks() const { print_owned_locks_on(tty); }
590 Mutex* owned_locks() const { return _owned_locks; }
591 bool owns_locks() const { return owned_locks() != NULL; }
592
593 // Deadlock detection
594 ResourceMark* current_resource_mark() { return _current_resource_mark; }
595 void set_current_resource_mark(ResourceMark* rm) { _current_resource_mark = rm; }
596 #endif // ASSERT
597
598 private:
599 volatile int _jvmti_env_iteration_count;
600
601 public:
602 void entering_jvmti_env_iteration() { ++_jvmti_env_iteration_count; }
603 void leaving_jvmti_env_iteration() { --_jvmti_env_iteration_count; }
604 bool is_inside_jvmti_env_iteration() { return _jvmti_env_iteration_count > 0; }
605
606 // Code generation
607 static ByteSize exception_file_offset() { return byte_offset_of(Thread, _exception_file); }
608 static ByteSize exception_line_offset() { return byte_offset_of(Thread, _exception_line); }
609 static ByteSize active_handles_offset() { return byte_offset_of(Thread, _active_handles); }
610
611 static ByteSize stack_base_offset() { return byte_offset_of(Thread, _stack_base); }
612 static ByteSize stack_size_offset() { return byte_offset_of(Thread, _stack_size); }
613
614 static ByteSize tlab_start_offset() { return byte_offset_of(Thread, _tlab) + ThreadLocalAllocBuffer::start_offset(); }
615 static ByteSize tlab_end_offset() { return byte_offset_of(Thread, _tlab) + ThreadLocalAllocBuffer::end_offset(); }
616 static ByteSize tlab_top_offset() { return byte_offset_of(Thread, _tlab) + ThreadLocalAllocBuffer::top_offset(); }
617 static ByteSize tlab_pf_top_offset() { return byte_offset_of(Thread, _tlab) + ThreadLocalAllocBuffer::pf_top_offset(); }
618
619 static ByteSize allocated_bytes_offset() { return byte_offset_of(Thread, _allocated_bytes); }
620
621 JFR_ONLY(DEFINE_THREAD_LOCAL_OFFSET_JFR;)
622
623 public:
624 ParkEvent * volatile _ParkEvent; // for Object monitors, JVMTI raw monitors,
625 // and ObjectSynchronizer::read_stable_mark
626
627 // Termination indicator used by the signal handler.
628 // _ParkEvent is just a convenient field we can NULL out after setting the JavaThread termination state
629 // (which can't itself be read from the signal handler if a signal hits during the Thread destructor).
630 bool has_terminated() { return Atomic::load(&_ParkEvent) == NULL; };
631
632 jint _hashStateW; // Marsaglia Shift-XOR thread-local RNG
633 jint _hashStateX; // thread-specific hashCode generator state
634 jint _hashStateY;
635 jint _hashStateZ;
636
637 // Low-level leaf-lock primitives used to implement synchronization.
638 // Not for general synchronization use.
639 static void SpinAcquire(volatile int * Lock, const char * Name);
640 static void SpinRelease(volatile int * Lock);
641
642 #if defined(__APPLE__) && defined(AARCH64)
643 private:
644 DEBUG_ONLY(bool _wx_init);
645 WXMode _wx_state;
646 public:
647 void init_wx();
648 WXMode enable_wx(WXMode new_state);
649
650 void assert_wx_state(WXMode expected) {
651 assert(_wx_state == expected, "wrong state");
652 }
653 #endif // __APPLE__ && AARCH64
654 };
655
656 // Inline implementation of Thread::current()
657 inline Thread* Thread::current() {
658 Thread* current = current_or_null();
659 assert(current != NULL, "Thread::current() called on detached thread");
660 return current;
661 }
662
663 inline Thread* Thread::current_or_null() {
664 #ifndef USE_LIBRARY_BASED_TLS_ONLY
665 return _thr_current;
666 #else
667 if (ThreadLocalStorage::is_initialized()) {
668 return ThreadLocalStorage::thread();
669 }
670 return NULL;
671 #endif
672 }
673
674 inline Thread* Thread::current_or_null_safe() {
675 if (ThreadLocalStorage::is_initialized()) {
676 return ThreadLocalStorage::thread();
677 }
678 return NULL;
679 }
680
681 class CompilerThread;
682
683 typedef void (*ThreadFunction)(JavaThread*, TRAPS);
684
685 class JavaThread: public Thread {
686 friend class VMStructs;
687 friend class JVMCIVMStructs;
688 friend class WhiteBox;
689 friend class VTBuffer;
690 friend class ThreadsSMRSupport; // to access _threadObj for exiting_threads_oops_do
691 friend class HandshakeState;
692 private:
693 bool _on_thread_list; // Is set when this JavaThread is added to the Threads list
694 OopHandle _threadObj; // The Java level thread object
695
696 #ifdef ASSERT
697 private:
698 int _java_call_counter;
699
700 public:
701 int java_call_counter() { return _java_call_counter; }
702 void inc_java_call_counter() { _java_call_counter++; }
703 void dec_java_call_counter() {
704 assert(_java_call_counter > 0, "Invalid nesting of JavaCallWrapper");
705 _java_call_counter--;
706 }
707 private: // restore original namespace restriction
708 #endif // ifdef ASSERT
709
710 JavaFrameAnchor _anchor; // Encapsulation of current java frame and it state
711
712 ThreadFunction _entry_point;
713
714 JNIEnv _jni_environment;
715
716 // Deopt support
717 DeoptResourceMark* _deopt_mark; // Holds special ResourceMark for deoptimization
718
719 CompiledMethod* _deopt_nmethod; // CompiledMethod that is currently being deoptimized
720 vframeArray* _vframe_array_head; // Holds the heap of the active vframeArrays
721 vframeArray* _vframe_array_last; // Holds last vFrameArray we popped
722 // Holds updates by JVMTI agents for compiled frames that cannot be performed immediately. They
723 // will be carried out as soon as possible which, in most cases, is just before deoptimization of
724 // the frame, when control returns to it.
725 JvmtiDeferredUpdates* _jvmti_deferred_updates;
726
727 // Handshake value for fixing 6243940. We need a place for the i2c
728 // adapter to store the callee Method*. This value is NEVER live
729 // across a gc point so it does NOT have to be gc'd
730 // The handshake is open ended since we can't be certain that it will
731 // be NULLed. This is because we rarely ever see the race and end up
732 // in handle_wrong_method which is the backend of the handshake. See
733 // code in i2c adapters and handle_wrong_method.
734
735 Method* _callee_target;
736
737 // Used to pass back results to the interpreter or generated code running Java code.
738 oop _vm_result; // oop result is GC-preserved
739 Metadata* _vm_result_2; // non-oop result
740 oop _return_buffered_value; // buffered value being returned
741
742 // See ReduceInitialCardMarks: this holds the precise space interval of
743 // the most recent slow path allocation for which compiled code has
744 // elided card-marks for performance along the fast-path.
745 MemRegion _deferred_card_mark;
746
747 ObjectMonitor* volatile _current_pending_monitor; // ObjectMonitor this thread is waiting to lock
748 bool _current_pending_monitor_is_from_java; // locking is from Java code
749 ObjectMonitor* volatile _current_waiting_monitor; // ObjectMonitor on which this thread called Object.wait()
750 public:
751 volatile intptr_t _Stalled;
752
753 // For tracking the heavyweight monitor the thread is pending on.
754 ObjectMonitor* current_pending_monitor() {
755 // Use Atomic::load() to prevent data race between concurrent modification and
756 // concurrent readers, e.g. ThreadService::get_current_contended_monitor().
757 // Especially, reloading pointer from thread after NULL check must be prevented.
758 return Atomic::load(&_current_pending_monitor);
759 }
760 void set_current_pending_monitor(ObjectMonitor* monitor) {
761 Atomic::store(&_current_pending_monitor, monitor);
762 }
763 void set_current_pending_monitor_is_from_java(bool from_java) {
764 _current_pending_monitor_is_from_java = from_java;
765 }
766 bool current_pending_monitor_is_from_java() {
767 return _current_pending_monitor_is_from_java;
768 }
769 ObjectMonitor* current_waiting_monitor() {
770 // See the comment in current_pending_monitor() above.
771 return Atomic::load(&_current_waiting_monitor);
772 }
773 void set_current_waiting_monitor(ObjectMonitor* monitor) {
774 Atomic::store(&_current_waiting_monitor, monitor);
775 }
776
777 private:
778 MonitorChunk* _monitor_chunks; // Contains the off stack monitors
779 // allocated during deoptimization
780 // and by JNI_MonitorEnter/Exit
781
782 enum SuspendFlags {
783 // NOTE: avoid using the sign-bit as cc generates different test code
784 // when the sign-bit is used, and sometimes incorrectly - see CR 6398077
785 _has_async_exception = 0x00000001U, // there is a pending async exception
786 _trace_flag = 0x00000004U, // call tracing backend
787 _obj_deopt = 0x00000008U // suspend for object reallocation and relocking for JVMTI agent
788 };
789
790 // various suspension related flags - atomically updated
791 // overloaded with async exceptions so that we do a single check when transitioning from native->Java
792 volatile uint32_t _suspend_flags;
793
794 inline void set_suspend_flag(SuspendFlags f);
795 inline void clear_suspend_flag(SuspendFlags f);
796
797 public:
798 inline void set_trace_flag();
799 inline void clear_trace_flag();
800 inline void set_obj_deopt_flag();
801 inline void clear_obj_deopt_flag();
802 bool is_trace_suspend() { return (_suspend_flags & _trace_flag) != 0; }
803 bool is_obj_deopt_suspend() { return (_suspend_flags & _obj_deopt) != 0; }
804
805 // Asynchronous exceptions support
806 private:
807 enum AsyncExceptionCondition {
808 _no_async_condition = 0,
809 _async_exception,
810 _async_unsafe_access_error
811 };
812 AsyncExceptionCondition _async_exception_condition;
813 oop _pending_async_exception;
814
815 void set_async_exception_condition(AsyncExceptionCondition aec) { _async_exception_condition = aec; }
816 AsyncExceptionCondition clear_async_exception_condition() {
817 AsyncExceptionCondition x = _async_exception_condition;
818 _async_exception_condition = _no_async_condition;
819 return x;
820 }
821
822 public:
823 bool has_async_exception_condition(bool check_unsafe_access_error = true) {
824 return check_unsafe_access_error ? _async_exception_condition != _no_async_condition
825 : _async_exception_condition == _async_exception;
826 }
827 inline void set_pending_async_exception(oop e);
828 void set_pending_unsafe_access_error() {
829 // Don't overwrite an asynchronous exception sent by another thread
830 if (_async_exception_condition == _no_async_condition) {
831 set_async_exception_condition(_async_unsafe_access_error);
832 }
833 }
834 void check_and_handle_async_exceptions();
835 // Installs a pending exception to be inserted later
836 static void send_async_exception(oop thread_oop, oop java_throwable);
837 void send_thread_stop(oop throwable);
838
839 // Safepoint support
840 public: // Expose _thread_state for SafeFetchInt()
841 volatile JavaThreadState _thread_state;
842 private:
843 SafepointMechanism::ThreadData _poll_data;
844 ThreadSafepointState* _safepoint_state; // Holds information about a thread during a safepoint
845 address _saved_exception_pc; // Saved pc of instruction where last implicit exception happened
846 NOT_PRODUCT(bool _requires_cross_modify_fence;) // State used by VerifyCrossModifyFence
847 #ifdef ASSERT
848 // Debug support for checking if code allows safepoints or not.
849 // Safepoints in the VM can happen because of allocation, invoking a VM operation, or blocking on
850 // mutex, or blocking on an object synchronizer (Java locking).
851 // If _no_safepoint_count is non-zero, then an assertion failure will happen in any of
852 // the above cases. The class NoSafepointVerifier is used to set this counter.
853 int _no_safepoint_count; // If 0, thread allow a safepoint to happen
854
855 public:
856 void inc_no_safepoint_count() { _no_safepoint_count++; }
857 void dec_no_safepoint_count() { _no_safepoint_count--; }
858 #endif // ASSERT
859 public:
860 // These functions check conditions before possibly going to a safepoint.
861 // including NoSafepointVerifier.
862 void check_for_valid_safepoint_state() NOT_DEBUG_RETURN;
863 void check_possible_safepoint() NOT_DEBUG_RETURN;
864
865 #ifdef ASSERT
866 private:
867 volatile uint64_t _visited_for_critical_count;
868
869 public:
870 void set_visited_for_critical_count(uint64_t safepoint_id) {
871 assert(_visited_for_critical_count == 0, "Must be reset before set");
872 assert((safepoint_id & 0x1) == 1, "Must be odd");
873 _visited_for_critical_count = safepoint_id;
874 }
875 void reset_visited_for_critical_count(uint64_t safepoint_id) {
876 assert(_visited_for_critical_count == safepoint_id, "Was not visited");
877 _visited_for_critical_count = 0;
878 }
879 bool was_visited_for_critical_count(uint64_t safepoint_id) const {
880 return _visited_for_critical_count == safepoint_id;
881 }
882 #endif // ASSERT
883
884 // JavaThread termination support
885 public:
886 enum TerminatedTypes {
887 _not_terminated = 0xDEAD - 2,
888 _thread_exiting, // JavaThread::exit() has been called for this thread
889 _thread_terminated, // JavaThread is removed from thread list
890 _vm_exited // JavaThread is still executing native code, but VM is terminated
891 // only VM_Exit can set _vm_exited
892 };
893
894 private:
895 // In general a JavaThread's _terminated field transitions as follows:
896 //
897 // _not_terminated => _thread_exiting => _thread_terminated
898 //
899 // _vm_exited is a special value to cover the case of a JavaThread
900 // executing native code after the VM itself is terminated.
901 volatile TerminatedTypes _terminated;
902
903 jint _in_deopt_handler; // count of deoptimization
904 // handlers thread is in
905 volatile bool _doing_unsafe_access; // Thread may fault due to unsafe access
906 bool _do_not_unlock_if_synchronized; // Do not unlock the receiver of a synchronized method (since it was
907 // never locked) when throwing an exception. Used by interpreter only.
908
909 // JNI attach states:
910 enum JNIAttachStates {
911 _not_attaching_via_jni = 1, // thread is not attaching via JNI
912 _attaching_via_jni, // thread is attaching via JNI
913 _attached_via_jni // thread has attached via JNI
914 };
915
916 // A regular JavaThread's _jni_attach_state is _not_attaching_via_jni.
917 // A native thread that is attaching via JNI starts with a value
918 // of _attaching_via_jni and transitions to _attached_via_jni.
919 volatile JNIAttachStates _jni_attach_state;
920
921
922 #if INCLUDE_JVMCI
923 // The _pending_* fields below are used to communicate extra information
924 // from an uncommon trap in JVMCI compiled code to the uncommon trap handler.
925
926 // Communicates the DeoptReason and DeoptAction of the uncommon trap
927 int _pending_deoptimization;
928
929 // Specifies whether the uncommon trap is to bci 0 of a synchronized method
930 // before the monitor has been acquired.
931 bool _pending_monitorenter;
932
933 // Specifies if the DeoptReason for the last uncommon trap was Reason_transfer_to_interpreter
934 bool _pending_transfer_to_interpreter;
935
936 // True if in a runtime call from compiled code that will deoptimize
937 // and re-execute a failed heap allocation in the interpreter.
938 bool _in_retryable_allocation;
939
940 // An id of a speculation that JVMCI compiled code can use to further describe and
941 // uniquely identify the speculative optimization guarded by an uncommon trap.
942 // See JVMCINMethodData::SPECULATION_LENGTH_BITS for further details.
943 jlong _pending_failed_speculation;
944
945 // These fields are mutually exclusive in terms of live ranges.
946 union {
947 // Communicates the pc at which the most recent implicit exception occurred
948 // from the signal handler to a deoptimization stub.
949 address _implicit_exception_pc;
950
951 // Communicates an alternative call target to an i2c stub from a JavaCall .
952 address _alternate_call_target;
953 } _jvmci;
954
955 // Support for high precision, thread sensitive counters in JVMCI compiled code.
956 jlong* _jvmci_counters;
957
958 // Fast thread locals for use by JVMCI
959 jlong _jvmci_reserved0;
960 jlong _jvmci_reserved1;
961 oop _jvmci_reserved_oop0;
962
963 public:
964 static jlong* _jvmci_old_thread_counters;
965 static void collect_counters(jlong* array, int length);
966
967 bool resize_counters(int current_size, int new_size);
968
969 static bool resize_all_jvmci_counters(int new_size);
970
971 void set_jvmci_reserved_oop0(oop value) {
972 _jvmci_reserved_oop0 = value;
973 }
974
975 oop get_jvmci_reserved_oop0() {
976 return _jvmci_reserved_oop0;
977 }
978
979 void set_jvmci_reserved0(jlong value) {
980 _jvmci_reserved0 = value;
981 }
982
983 jlong get_jvmci_reserved0() {
984 return _jvmci_reserved0;
985 }
986
987 void set_jvmci_reserved1(jlong value) {
988 _jvmci_reserved1 = value;
989 }
990
991 jlong get_jvmci_reserved1() {
992 return _jvmci_reserved1;
993 }
994
995 private:
996 #endif // INCLUDE_JVMCI
997
998 StackOverflow _stack_overflow_state;
999
1000 // Compiler exception handling (NOTE: The _exception_oop is *NOT* the same as _pending_exception. It is
1001 // used to temp. parsing values into and out of the runtime system during exception handling for compiled
1002 // code)
1003 volatile oop _exception_oop; // Exception thrown in compiled code
1004 volatile address _exception_pc; // PC where exception happened
1005 volatile address _exception_handler_pc; // PC for handler of exception
1006 volatile int _is_method_handle_return; // true (== 1) if the current exception PC is a MethodHandle call site.
1007
1008 private:
1009 // support for JNI critical regions
1010 jint _jni_active_critical; // count of entries into JNI critical region
1011
1012 // Checked JNI: function name requires exception check
1013 char* _pending_jni_exception_check_fn;
1014
1015 // For deadlock detection.
1016 int _depth_first_number;
1017
1018 // JVMTI PopFrame support
1019 // This is set to popframe_pending to signal that top Java frame should be popped immediately
1020 int _popframe_condition;
1021
1022 // If reallocation of scalar replaced objects fails, we throw OOM
1023 // and during exception propagation, pop the top
1024 // _frames_to_pop_failed_realloc frames, the ones that reference
1025 // failed reallocations.
1026 int _frames_to_pop_failed_realloc;
1027
1028 friend class VMThread;
1029 friend class ThreadWaitTransition;
1030 friend class VM_Exit;
1031
1032 // Stack watermark barriers.
1033 StackWatermarks _stack_watermarks;
1034
1035 public:
1036 inline StackWatermarks* stack_watermarks() { return &_stack_watermarks; }
1037
1038 public:
1039 // Constructor
1040 JavaThread(); // delegating constructor
1041 JavaThread(bool is_attaching_via_jni); // for main thread and JNI attached threads
1042 JavaThread(ThreadFunction entry_point, size_t stack_size = 0);
1043 ~JavaThread();
1044
1045 #ifdef ASSERT
1046 // verify this JavaThread hasn't be published in the Threads::list yet
1047 void verify_not_published();
1048 #endif // ASSERT
1049
1050 StackOverflow* stack_overflow_state() { return &_stack_overflow_state; }
1051
1052 //JNI functiontable getter/setter for JVMTI jni function table interception API.
1053 void set_jni_functions(struct JNINativeInterface_* functionTable) {
1054 _jni_environment.functions = functionTable;
1055 }
1056 struct JNINativeInterface_* get_jni_functions() {
1057 return (struct JNINativeInterface_ *)_jni_environment.functions;
1058 }
1059
1060 // This function is called at thread creation to allow
1061 // platform specific thread variables to be initialized.
1062 void cache_global_variables();
1063
1064 // Executes Shutdown.shutdown()
1065 void invoke_shutdown_hooks();
1066
1067 // Cleanup on thread exit
1068 enum ExitType {
1069 normal_exit,
1070 jni_detach
1071 };
1072 void exit(bool destroy_vm, ExitType exit_type = normal_exit);
1073
1074 void cleanup_failed_attach_current_thread(bool is_daemon);
1075
1076 // Testers
1077 virtual bool is_Java_thread() const { return true; }
1078 virtual bool can_call_java() const { return true; }
1079
1080 virtual bool is_active_Java_thread() const {
1081 return on_thread_list() && !is_terminated();
1082 }
1083
1084 // Thread oop. threadObj() can be NULL for initial JavaThread
1085 // (or for threads attached via JNI)
1086 oop threadObj() const;
1087 void set_threadObj(oop p);
1088
1089 // Prepare thread and add to priority queue. If a priority is
1090 // not specified, use the priority of the thread object. Threads_lock
1091 // must be held while this function is called.
1092 void prepare(jobject jni_thread, ThreadPriority prio=NoPriority);
1093
1094 void set_saved_exception_pc(address pc) { _saved_exception_pc = pc; }
1095 address saved_exception_pc() { return _saved_exception_pc; }
1096
1097 ThreadFunction entry_point() const { return _entry_point; }
1098
1099 // Allocates a new Java level thread object for this thread. thread_name may be NULL.
1100 void allocate_threadObj(Handle thread_group, const char* thread_name, bool daemon, TRAPS);
1101
1102 // Last frame anchor routines
1103
1104 JavaFrameAnchor* frame_anchor(void) { return &_anchor; }
1105
1106 // last_Java_sp
1107 bool has_last_Java_frame() const { return _anchor.has_last_Java_frame(); }
1108 intptr_t* last_Java_sp() const { return _anchor.last_Java_sp(); }
1109
1110 // last_Java_pc
1111
1112 address last_Java_pc(void) { return _anchor.last_Java_pc(); }
1113
1114 // Safepoint support
1115 inline JavaThreadState thread_state() const;
1116 inline void set_thread_state(JavaThreadState s);
1117 inline void set_thread_state_fence(JavaThreadState s); // fence after setting thread state
1118 inline ThreadSafepointState* safepoint_state() const;
1119 inline void set_safepoint_state(ThreadSafepointState* state);
1120 inline bool is_at_poll_safepoint();
1121
1122 // JavaThread termination and lifecycle support:
1123 void smr_delete();
1124 bool on_thread_list() const { return _on_thread_list; }
1125 void set_on_thread_list() { _on_thread_list = true; }
1126
1127 // thread has called JavaThread::exit() or is terminated
1128 bool is_exiting() const;
1129 // thread is terminated (no longer on the threads list); we compare
1130 // against the two non-terminated values so that a freed JavaThread
1131 // will also be considered terminated.
1132 bool check_is_terminated(TerminatedTypes l_terminated) const {
1133 return l_terminated != _not_terminated && l_terminated != _thread_exiting;
1134 }
1135 bool is_terminated() const;
1136 void set_terminated(TerminatedTypes t);
1137
1138 void block_if_vm_exited();
1139
1140 bool doing_unsafe_access() { return _doing_unsafe_access; }
1141 void set_doing_unsafe_access(bool val) { _doing_unsafe_access = val; }
1142
1143 bool do_not_unlock_if_synchronized() { return _do_not_unlock_if_synchronized; }
1144 void set_do_not_unlock_if_synchronized(bool val) { _do_not_unlock_if_synchronized = val; }
1145
1146 SafepointMechanism::ThreadData* poll_data() { return &_poll_data; }
1147
1148 void set_requires_cross_modify_fence(bool val) PRODUCT_RETURN NOT_PRODUCT({ _requires_cross_modify_fence = val; })
1149
1150 private:
1151 DEBUG_ONLY(void verify_frame_info();)
1152
1153 // Support for thread handshake operations
1154 HandshakeState _handshake;
1155 public:
1156 HandshakeState* handshake_state() { return &_handshake; }
1157
1158 // A JavaThread can always safely operate on it self and other threads
1159 // can do it safely if they are the active handshaker.
1160 bool is_handshake_safe_for(Thread* th) const {
1161 return _handshake.active_handshaker() == th || this == th;
1162 }
1163
1164 // Suspend/resume support for JavaThread
1165 bool java_suspend(); // higher-level suspension logic called by the public APIs
1166 bool java_resume(); // higher-level resume logic called by the public APIs
1167 bool is_suspended() { return _handshake.is_suspended(); }
1168
1169 // Check for async exception in addition to safepoint.
1170 static void check_special_condition_for_native_trans(JavaThread *thread);
1171
1172 // Synchronize with another thread that is deoptimizing objects of the
1173 // current thread, i.e. reverts optimizations based on escape analysis.
1174 void wait_for_object_deoptimization();
1175
1176 // these next two are also used for self-suspension and async exception support
1177 void handle_special_runtime_exit_condition(bool check_asyncs = true);
1178
1179 // Return true if JavaThread has an asynchronous condition or
1180 // if external suspension is requested.
1181 bool has_special_runtime_exit_condition() {
1182 return (_async_exception_condition != _no_async_condition) ||
1183 (_suspend_flags & (_obj_deopt JFR_ONLY(| _trace_flag))) != 0;
1184 }
1185
1186 // Fast-locking support
1187 bool is_lock_owned(address adr) const;
1188
1189 // Accessors for vframe array top
1190 // The linked list of vframe arrays are sorted on sp. This means when we
1191 // unpack the head must contain the vframe array to unpack.
1192 void set_vframe_array_head(vframeArray* value) { _vframe_array_head = value; }
1193 vframeArray* vframe_array_head() const { return _vframe_array_head; }
1194
1195 // Side structure for deferring update of java frame locals until deopt occurs
1196 JvmtiDeferredUpdates* deferred_updates() const { return _jvmti_deferred_updates; }
1197 void set_deferred_updates(JvmtiDeferredUpdates* du) { _jvmti_deferred_updates = du; }
1198
1199 // These only really exist to make debugging deopt problems simpler
1200
1201 void set_vframe_array_last(vframeArray* value) { _vframe_array_last = value; }
1202 vframeArray* vframe_array_last() const { return _vframe_array_last; }
1203
1204 // The special resourceMark used during deoptimization
1205
1206 void set_deopt_mark(DeoptResourceMark* value) { _deopt_mark = value; }
1207 DeoptResourceMark* deopt_mark(void) { return _deopt_mark; }
1208
1209 void set_deopt_compiled_method(CompiledMethod* nm) { _deopt_nmethod = nm; }
1210 CompiledMethod* deopt_compiled_method() { return _deopt_nmethod; }
1211
1212 Method* callee_target() const { return _callee_target; }
1213 void set_callee_target (Method* x) { _callee_target = x; }
1214
1215 // Oop results of vm runtime calls
1216 oop vm_result() const { return _vm_result; }
1217 void set_vm_result (oop x) { _vm_result = x; }
1218
1219 Metadata* vm_result_2() const { return _vm_result_2; }
1220 void set_vm_result_2 (Metadata* x) { _vm_result_2 = x; }
1221
1222 oop return_buffered_value() const { return _return_buffered_value; }
1223 void set_return_buffered_value(oop val) { _return_buffered_value = val; }
1224
1225 MemRegion deferred_card_mark() const { return _deferred_card_mark; }
1226 void set_deferred_card_mark(MemRegion mr) { _deferred_card_mark = mr; }
1227
1228 #if INCLUDE_JVMCI
1229 int pending_deoptimization() const { return _pending_deoptimization; }
1230 jlong pending_failed_speculation() const { return _pending_failed_speculation; }
1231 bool has_pending_monitorenter() const { return _pending_monitorenter; }
1232 void set_pending_monitorenter(bool b) { _pending_monitorenter = b; }
1233 void set_pending_deoptimization(int reason) { _pending_deoptimization = reason; }
1234 void set_pending_failed_speculation(jlong failed_speculation) { _pending_failed_speculation = failed_speculation; }
1235 void set_pending_transfer_to_interpreter(bool b) { _pending_transfer_to_interpreter = b; }
1236 void set_jvmci_alternate_call_target(address a) { assert(_jvmci._alternate_call_target == NULL, "must be"); _jvmci._alternate_call_target = a; }
1237 void set_jvmci_implicit_exception_pc(address a) { assert(_jvmci._implicit_exception_pc == NULL, "must be"); _jvmci._implicit_exception_pc = a; }
1238
1239 virtual bool in_retryable_allocation() const { return _in_retryable_allocation; }
1240 void set_in_retryable_allocation(bool b) { _in_retryable_allocation = b; }
1241 #endif // INCLUDE_JVMCI
1242
1243 // Exception handling for compiled methods
1244 oop exception_oop() const;
1245 address exception_pc() const { return _exception_pc; }
1246 address exception_handler_pc() const { return _exception_handler_pc; }
1247 bool is_method_handle_return() const { return _is_method_handle_return == 1; }
1248
1249 void set_exception_oop(oop o);
1250 void set_exception_pc(address a) { _exception_pc = a; }
1251 void set_exception_handler_pc(address a) { _exception_handler_pc = a; }
1252 void set_is_method_handle_return(bool value) { _is_method_handle_return = value ? 1 : 0; }
1253
1254 void clear_exception_oop_and_pc() {
1255 set_exception_oop(NULL);
1256 set_exception_pc(NULL);
1257 }
1258
1259 // Check if address is in the usable part of the stack (excludes protected
1260 // guard pages). Can be applied to any thread and is an approximation for
1261 // using is_in_live_stack when the query has to happen from another thread.
1262 bool is_in_usable_stack(address adr) const {
1263 return is_in_stack_range_incl(adr, _stack_overflow_state.stack_reserved_zone_base());
1264 }
1265
1266 // Misc. accessors/mutators
1267 void set_do_not_unlock(void) { _do_not_unlock_if_synchronized = true; }
1268 void clr_do_not_unlock(void) { _do_not_unlock_if_synchronized = false; }
1269 bool do_not_unlock(void) { return _do_not_unlock_if_synchronized; }
1270
1271 // For assembly stub generation
1272 static ByteSize threadObj_offset() { return byte_offset_of(JavaThread, _threadObj); }
1273 static ByteSize jni_environment_offset() { return byte_offset_of(JavaThread, _jni_environment); }
1274 static ByteSize pending_jni_exception_check_fn_offset() {
1275 return byte_offset_of(JavaThread, _pending_jni_exception_check_fn);
1276 }
1277 static ByteSize last_Java_sp_offset() {
1278 return byte_offset_of(JavaThread, _anchor) + JavaFrameAnchor::last_Java_sp_offset();
1279 }
1280 static ByteSize last_Java_pc_offset() {
1281 return byte_offset_of(JavaThread, _anchor) + JavaFrameAnchor::last_Java_pc_offset();
1282 }
1283 static ByteSize frame_anchor_offset() {
1284 return byte_offset_of(JavaThread, _anchor);
1285 }
1286 static ByteSize callee_target_offset() { return byte_offset_of(JavaThread, _callee_target); }
1287 static ByteSize vm_result_offset() { return byte_offset_of(JavaThread, _vm_result); }
1288 static ByteSize vm_result_2_offset() { return byte_offset_of(JavaThread, _vm_result_2); }
1289 static ByteSize return_buffered_value_offset() { return byte_offset_of(JavaThread, _return_buffered_value); }
1290 static ByteSize thread_state_offset() { return byte_offset_of(JavaThread, _thread_state); }
1291 static ByteSize polling_word_offset() { return byte_offset_of(JavaThread, _poll_data) + byte_offset_of(SafepointMechanism::ThreadData, _polling_word);}
1292 static ByteSize polling_page_offset() { return byte_offset_of(JavaThread, _poll_data) + byte_offset_of(SafepointMechanism::ThreadData, _polling_page);}
1293 static ByteSize saved_exception_pc_offset() { return byte_offset_of(JavaThread, _saved_exception_pc); }
1294 static ByteSize osthread_offset() { return byte_offset_of(JavaThread, _osthread); }
1295 #if INCLUDE_JVMCI
1296 static ByteSize pending_deoptimization_offset() { return byte_offset_of(JavaThread, _pending_deoptimization); }
1297 static ByteSize pending_monitorenter_offset() { return byte_offset_of(JavaThread, _pending_monitorenter); }
1298 static ByteSize pending_failed_speculation_offset() { return byte_offset_of(JavaThread, _pending_failed_speculation); }
1299 static ByteSize jvmci_alternate_call_target_offset() { return byte_offset_of(JavaThread, _jvmci._alternate_call_target); }
1300 static ByteSize jvmci_implicit_exception_pc_offset() { return byte_offset_of(JavaThread, _jvmci._implicit_exception_pc); }
1301 static ByteSize jvmci_counters_offset() { return byte_offset_of(JavaThread, _jvmci_counters); }
1302 #endif // INCLUDE_JVMCI
1303 static ByteSize exception_oop_offset() { return byte_offset_of(JavaThread, _exception_oop); }
1304 static ByteSize exception_pc_offset() { return byte_offset_of(JavaThread, _exception_pc); }
1305 static ByteSize exception_handler_pc_offset() { return byte_offset_of(JavaThread, _exception_handler_pc); }
1306 static ByteSize is_method_handle_return_offset() { return byte_offset_of(JavaThread, _is_method_handle_return); }
1307
1308 // StackOverflow offsets
1309 static ByteSize stack_overflow_limit_offset() {
1310 return byte_offset_of(JavaThread, _stack_overflow_state._stack_overflow_limit);
1311 }
1312 static ByteSize stack_guard_state_offset() {
1313 return byte_offset_of(JavaThread, _stack_overflow_state._stack_guard_state);
1314 }
1315 static ByteSize reserved_stack_activation_offset() {
1316 return byte_offset_of(JavaThread, _stack_overflow_state._reserved_stack_activation);
1317 }
1318
1319 static ByteSize suspend_flags_offset() { return byte_offset_of(JavaThread, _suspend_flags); }
1320
1321 static ByteSize do_not_unlock_if_synchronized_offset() { return byte_offset_of(JavaThread, _do_not_unlock_if_synchronized); }
1322 static ByteSize should_post_on_exceptions_flag_offset() {
1323 return byte_offset_of(JavaThread, _should_post_on_exceptions_flag);
1324 }
1325 static ByteSize doing_unsafe_access_offset() { return byte_offset_of(JavaThread, _doing_unsafe_access); }
1326 NOT_PRODUCT(static ByteSize requires_cross_modify_fence_offset() { return byte_offset_of(JavaThread, _requires_cross_modify_fence); })
1327
1328 // Returns the jni environment for this thread
1329 JNIEnv* jni_environment() { return &_jni_environment; }
1330
1331 static JavaThread* thread_from_jni_environment(JNIEnv* env) {
1332 JavaThread *thread_from_jni_env = (JavaThread*)((intptr_t)env - in_bytes(jni_environment_offset()));
1333 // Only return NULL if thread is off the thread list; starting to
1334 // exit should not return NULL.
1335 if (thread_from_jni_env->is_terminated()) {
1336 thread_from_jni_env->block_if_vm_exited();
1337 return NULL;
1338 } else {
1339 return thread_from_jni_env;
1340 }
1341 }
1342
1343 // JNI critical regions. These can nest.
1344 bool in_critical() { return _jni_active_critical > 0; }
1345 bool in_last_critical() { return _jni_active_critical == 1; }
1346 inline void enter_critical();
1347 void exit_critical() {
1348 assert(Thread::current() == this, "this must be current thread");
1349 _jni_active_critical--;
1350 assert(_jni_active_critical >= 0, "JNI critical nesting problem?");
1351 }
1352
1353 // Checked JNI: is the programmer required to check for exceptions, if so specify
1354 // which function name. Returning to a Java frame should implicitly clear the
1355 // pending check, this is done for Native->Java transitions (i.e. user JNI code).
1356 // VM->Java transistions are not cleared, it is expected that JNI code enclosed
1357 // within ThreadToNativeFromVM makes proper exception checks (i.e. VM internal).
1358 bool is_pending_jni_exception_check() const { return _pending_jni_exception_check_fn != NULL; }
1359 void clear_pending_jni_exception_check() { _pending_jni_exception_check_fn = NULL; }
1360 const char* get_pending_jni_exception_check() const { return _pending_jni_exception_check_fn; }
1361 void set_pending_jni_exception_check(const char* fn_name) { _pending_jni_exception_check_fn = (char*) fn_name; }
1362
1363 // For deadlock detection
1364 int depth_first_number() { return _depth_first_number; }
1365 void set_depth_first_number(int dfn) { _depth_first_number = dfn; }
1366
1367 private:
1368 void set_monitor_chunks(MonitorChunk* monitor_chunks) { _monitor_chunks = monitor_chunks; }
1369
1370 public:
1371 MonitorChunk* monitor_chunks() const { return _monitor_chunks; }
1372 void add_monitor_chunk(MonitorChunk* chunk);
1373 void remove_monitor_chunk(MonitorChunk* chunk);
1374 bool in_deopt_handler() const { return _in_deopt_handler > 0; }
1375 void inc_in_deopt_handler() { _in_deopt_handler++; }
1376 void dec_in_deopt_handler() {
1377 assert(_in_deopt_handler > 0, "mismatched deopt nesting");
1378 if (_in_deopt_handler > 0) { // robustness
1379 _in_deopt_handler--;
1380 }
1381 }
1382
1383 private:
1384 void set_entry_point(ThreadFunction entry_point) { _entry_point = entry_point; }
1385
1386 // factor out low-level mechanics for use in both normal and error cases
1387 const char* get_thread_name_string(char* buf = NULL, int buflen = 0) const;
1388
1389 public:
1390
1391 // Frame iteration; calls the function f for all frames on the stack
1392 void frames_do(void f(frame*, const RegisterMap*));
1393
1394 // Memory operations
1395 void oops_do_frames(OopClosure* f, CodeBlobClosure* cf);
1396 void oops_do_no_frames(OopClosure* f, CodeBlobClosure* cf);
1397
1398 // Sweeper operations
1399 virtual void nmethods_do(CodeBlobClosure* cf);
1400
1401 // RedefineClasses Support
1402 void metadata_do(MetadataClosure* f);
1403
1404 // Debug method asserting thread states are correct during a handshake operation.
1405 DEBUG_ONLY(void verify_states_for_handshake();)
1406
1407 // Misc. operations
1408 const char* name() const;
1409 const char* type_name() const { return "JavaThread"; }
1410 static const char* name_for(oop thread_obj);
1411
1412 void print_on(outputStream* st, bool print_extended_info) const;
1413 void print_on(outputStream* st) const { print_on(st, false); }
1414 void print() const;
1415 void print_thread_state_on(outputStream*) const PRODUCT_RETURN;
1416 void print_on_error(outputStream* st, char* buf, int buflen) const;
1417 void print_name_on_error(outputStream* st, char* buf, int buflen) const;
1418 void verify();
1419
1420 // Accessing frames
1421 frame last_frame() {
1422 _anchor.make_walkable(this);
1423 return pd_last_frame();
1424 }
1425 javaVFrame* last_java_vframe(RegisterMap* reg_map);
1426
1427 // Returns method at 'depth' java or native frames down the stack
1428 // Used for security checks
1429 Klass* security_get_caller_class(int depth);
1430
1431 // Print stack trace in external format
1432 void print_stack_on(outputStream* st);
1433 void print_stack() { print_stack_on(tty); }
1434
1435 // Print stack traces in various internal formats
1436 void trace_stack() PRODUCT_RETURN;
1437 void trace_stack_from(vframe* start_vf) PRODUCT_RETURN;
1438 void trace_frames() PRODUCT_RETURN;
1439
1440 // Print an annotated view of the stack frames
1441 void print_frame_layout(int depth = 0, bool validate_only = false) NOT_DEBUG_RETURN;
1442 void validate_frame_layout() {
1443 print_frame_layout(0, true);
1444 }
1445
1446 // Function for testing deoptimization
1447 void deoptimize();
1448 void make_zombies();
1449
1450 void deoptimize_marked_methods();
1451
1452 public:
1453 // Returns the running thread as a JavaThread
1454 static JavaThread* current() {
1455 return JavaThread::cast(Thread::current());
1456 }
1457
1458 // Returns the current thread as a JavaThread, or NULL if not attached
1459 static inline JavaThread* current_or_null();
1460
1461 // Casts
1462 static JavaThread* cast(Thread* t) {
1463 assert(t->is_Java_thread(), "incorrect cast to JavaThread");
1464 return static_cast<JavaThread*>(t);
1465 }
1466
1467 static const JavaThread* cast(const Thread* t) {
1468 assert(t->is_Java_thread(), "incorrect cast to const JavaThread");
1469 return static_cast<const JavaThread*>(t);
1470 }
1471
1472 // Returns the active Java thread. Do not use this if you know you are calling
1473 // from a JavaThread, as it's slower than JavaThread::current. If called from
1474 // the VMThread, it also returns the JavaThread that instigated the VMThread's
1475 // operation. You may not want that either.
1476 static JavaThread* active();
1477
1478 protected:
1479 virtual void pre_run();
1480 virtual void run();
1481 void thread_main_inner();
1482 virtual void post_run();
1483
1484 public:
1485 // Thread local information maintained by JVMTI.
1486 void set_jvmti_thread_state(JvmtiThreadState *value) { _jvmti_thread_state = value; }
1487 // A JvmtiThreadState is lazily allocated. This jvmti_thread_state()
1488 // getter is used to get this JavaThread's JvmtiThreadState if it has
1489 // one which means NULL can be returned. JvmtiThreadState::state_for()
1490 // is used to get the specified JavaThread's JvmtiThreadState if it has
1491 // one or it allocates a new JvmtiThreadState for the JavaThread and
1492 // returns it. JvmtiThreadState::state_for() will return NULL only if
1493 // the specified JavaThread is exiting.
1494 JvmtiThreadState *jvmti_thread_state() const { return _jvmti_thread_state; }
1495 static ByteSize jvmti_thread_state_offset() { return byte_offset_of(JavaThread, _jvmti_thread_state); }
1496
1497 // JVMTI PopFrame support
1498 // Setting and clearing popframe_condition
1499 // All of these enumerated values are bits. popframe_pending
1500 // indicates that a PopFrame() has been requested and not yet been
1501 // completed. popframe_processing indicates that that PopFrame() is in
1502 // the process of being completed. popframe_force_deopt_reexecution_bit
1503 // indicates that special handling is required when returning to a
1504 // deoptimized caller.
1505 enum PopCondition {
1506 popframe_inactive = 0x00,
1507 popframe_pending_bit = 0x01,
1508 popframe_processing_bit = 0x02,
1509 popframe_force_deopt_reexecution_bit = 0x04
1510 };
1511 PopCondition popframe_condition() { return (PopCondition) _popframe_condition; }
1512 void set_popframe_condition(PopCondition c) { _popframe_condition = c; }
1513 void set_popframe_condition_bit(PopCondition c) { _popframe_condition |= c; }
1514 void clear_popframe_condition() { _popframe_condition = popframe_inactive; }
1515 static ByteSize popframe_condition_offset() { return byte_offset_of(JavaThread, _popframe_condition); }
1516 bool has_pending_popframe() { return (popframe_condition() & popframe_pending_bit) != 0; }
1517 bool popframe_forcing_deopt_reexecution() { return (popframe_condition() & popframe_force_deopt_reexecution_bit) != 0; }
1518 void clear_popframe_forcing_deopt_reexecution() { _popframe_condition &= ~popframe_force_deopt_reexecution_bit; }
1519
1520 bool pop_frame_in_process(void) { return ((_popframe_condition & popframe_processing_bit) != 0); }
1521 void set_pop_frame_in_process(void) { _popframe_condition |= popframe_processing_bit; }
1522 void clr_pop_frame_in_process(void) { _popframe_condition &= ~popframe_processing_bit; }
1523
1524 int frames_to_pop_failed_realloc() const { return _frames_to_pop_failed_realloc; }
1525 void set_frames_to_pop_failed_realloc(int nb) { _frames_to_pop_failed_realloc = nb; }
1526 void dec_frames_to_pop_failed_realloc() { _frames_to_pop_failed_realloc--; }
1527
1528 private:
1529 // Saved incoming arguments to popped frame.
1530 // Used only when popped interpreted frame returns to deoptimized frame.
1531 void* _popframe_preserved_args;
1532 int _popframe_preserved_args_size;
1533
1534 public:
1535 void popframe_preserve_args(ByteSize size_in_bytes, void* start);
1536 void* popframe_preserved_args();
1537 ByteSize popframe_preserved_args_size();
1538 WordSize popframe_preserved_args_size_in_words();
1539 void popframe_free_preserved_args();
1540
1541
1542 private:
1543 JvmtiThreadState *_jvmti_thread_state;
1544
1545 // Used by the interpreter in fullspeed mode for frame pop, method
1546 // entry, method exit and single stepping support. This field is
1547 // only set to non-zero at a safepoint or using a direct handshake
1548 // (see EnterInterpOnlyModeClosure).
1549 // It can be set to zero asynchronously to this threads execution (i.e., without
1550 // safepoint/handshake or a lock) so we have to be very careful.
1551 // Accesses by other threads are synchronized using JvmtiThreadState_lock though.
1552 int _interp_only_mode;
1553
1554 public:
1555 // used by the interpreter for fullspeed debugging support (see above)
1556 static ByteSize interp_only_mode_offset() { return byte_offset_of(JavaThread, _interp_only_mode); }
1557 bool is_interp_only_mode() { return (_interp_only_mode != 0); }
1558 int get_interp_only_mode() { return _interp_only_mode; }
1559 void increment_interp_only_mode() { ++_interp_only_mode; }
1560 void decrement_interp_only_mode() { --_interp_only_mode; }
1561
1562 // support for cached flag that indicates whether exceptions need to be posted for this thread
1563 // if this is false, we can avoid deoptimizing when events are thrown
1564 // this gets set to reflect whether jvmtiExport::post_exception_throw would actually do anything
1565 private:
1566 int _should_post_on_exceptions_flag;
1567
1568 public:
1569 int should_post_on_exceptions_flag() { return _should_post_on_exceptions_flag; }
1570 void set_should_post_on_exceptions_flag(int val) { _should_post_on_exceptions_flag = val; }
1571
1572 private:
1573 ThreadStatistics *_thread_stat;
1574
1575 public:
1576 ThreadStatistics* get_thread_stat() const { return _thread_stat; }
1577
1578 // Return a blocker object for which this thread is blocked parking.
1579 oop current_park_blocker();
1580
1581 private:
1582 static size_t _stack_size_at_create;
1583
1584 public:
1585 static inline size_t stack_size_at_create(void) {
1586 return _stack_size_at_create;
1587 }
1588 static inline void set_stack_size_at_create(size_t value) {
1589 _stack_size_at_create = value;
1590 }
1591
1592 // Machine dependent stuff
1593 #include OS_CPU_HEADER(thread)
1594
1595 // JSR166 per-thread parker
1596 private:
1597 Parker _parker;
1598 public:
1599 Parker* parker() { return &_parker; }
1600
1601 public:
1602 // clearing/querying jni attach status
1603 bool is_attaching_via_jni() const { return _jni_attach_state == _attaching_via_jni; }
1604 bool has_attached_via_jni() const { return is_attaching_via_jni() || _jni_attach_state == _attached_via_jni; }
1605 inline void set_done_attaching_via_jni();
1606
1607 // Stack dump assistance:
1608 // Track the class we want to initialize but for which we have to wait
1609 // on its init_lock() because it is already being initialized.
1610 void set_class_to_be_initialized(InstanceKlass* k);
1611 InstanceKlass* class_to_be_initialized() const;
1612
1613 private:
1614 InstanceKlass* _class_to_be_initialized;
1615
1616 // java.lang.Thread.sleep support
1617 ParkEvent * _SleepEvent;
1618 public:
1619 bool sleep(jlong millis);
1620
1621 // java.lang.Thread interruption support
1622 void interrupt();
1623 bool is_interrupted(bool clear_interrupted);
1624
1625 static OopStorage* thread_oop_storage();
1626
1627 static void verify_cross_modify_fence_failure(JavaThread *thread) PRODUCT_RETURN;
1628
1629 // Helper function to create the java.lang.Thread object for a
1630 // VM-internal thread. The thread will have the given name, be
1631 // part of the System ThreadGroup and if is_visible is true will be
1632 // discoverable via the system ThreadGroup.
1633 static Handle create_system_thread_object(const char* name, bool is_visible, TRAPS);
1634
1635 // Helper function to start a VM-internal daemon thread.
1636 // E.g. ServiceThread, NotificationThread, CompilerThread etc.
1637 static void start_internal_daemon(JavaThread* current, JavaThread* target,
1638 Handle thread_oop, ThreadPriority prio);
1639
1640 // Helper function to do vm_exit_on_initialization for osthread
1641 // resource allocation failure.
1642 static void vm_exit_on_osthread_failure(JavaThread* thread);
1643 };
1644
1645 inline JavaThread* JavaThread::current_or_null() {
1646 Thread* current = Thread::current_or_null();
1647 return current != nullptr ? JavaThread::cast(current) : nullptr;
1648 }
1649
1650 // The active thread queue. It also keeps track of the current used
1651 // thread priorities.
1652 class Threads: AllStatic {
1653 friend class VMStructs;
1654 private:
1655 static int _number_of_threads;
1656 static int _number_of_non_daemon_threads;
1657 static int _return_code;
1658 static uintx _thread_claim_token;
1659 #ifdef ASSERT
1660 static bool _vm_complete;
1661 #endif
1662
1663 static void initialize_java_lang_classes(JavaThread* main_thread, TRAPS);
1664 static void initialize_jsr292_core_classes(TRAPS);
1665
1666 public:
1667 // Thread management
1668 // force_daemon is a concession to JNI, where we may need to add a
1669 // thread to the thread list before allocating its thread object
1670 static void add(JavaThread* p, bool force_daemon = false);
1671 static void remove(JavaThread* p, bool is_daemon);
1672 static void non_java_threads_do(ThreadClosure* tc);
1673 static void java_threads_do(ThreadClosure* tc);
1674 static void java_threads_and_vm_thread_do(ThreadClosure* tc);
1675 static void threads_do(ThreadClosure* tc);
1676 static void possibly_parallel_threads_do(bool is_par, ThreadClosure* tc);
1677
1678 // Initializes the vm and creates the vm thread
1679 static jint create_vm(JavaVMInitArgs* args, bool* canTryAgain);
1680 static void convert_vm_init_libraries_to_agents();
1681 static void create_vm_init_libraries();
1682 static void create_vm_init_agents();
1683 static void shutdown_vm_agents();
1684 static void destroy_vm();
1685 // Supported VM versions via JNI
1686 // Includes JNI_VERSION_1_1
1687 static jboolean is_supported_jni_version_including_1_1(jint version);
1688 // Does not include JNI_VERSION_1_1
1689 static jboolean is_supported_jni_version(jint version);
1690
1691 // The "thread claim token" provides a way for threads to be claimed
1692 // by parallel worker tasks.
1693 //
1694 // Each thread contains a "token" field. A task will claim the
1695 // thread only if its token is different from the global token,
1696 // which is updated by calling change_thread_claim_token(). When
1697 // a thread is claimed, it's token is set to the global token value
1698 // so other threads in the same iteration pass won't claim it.
1699 //
1700 // For this to work change_thread_claim_token() needs to be called
1701 // exactly once in sequential code before starting parallel tasks
1702 // that should claim threads.
1703 //
1704 // New threads get their token set to 0 and change_thread_claim_token()
1705 // never sets the global token to 0.
1706 static uintx thread_claim_token() { return _thread_claim_token; }
1707 static void change_thread_claim_token();
1708 static void assert_all_threads_claimed() NOT_DEBUG_RETURN;
1709
1710 // Apply "f->do_oop" to all root oops in all threads.
1711 // This version may only be called by sequential code.
1712 static void oops_do(OopClosure* f, CodeBlobClosure* cf);
1713 // This version may be called by sequential or parallel code.
1714 static void possibly_parallel_oops_do(bool is_par, OopClosure* f, CodeBlobClosure* cf);
1715
1716 // RedefineClasses support
1717 static void metadata_do(MetadataClosure* f);
1718 static void metadata_handles_do(void f(Metadata*));
1719
1720 #ifdef ASSERT
1721 static bool is_vm_complete() { return _vm_complete; }
1722 #endif // ASSERT
1723
1724 // Verification
1725 static void verify();
1726 static void print_on(outputStream* st, bool print_stacks, bool internal_format, bool print_concurrent_locks, bool print_extended_info);
1727 static void print(bool print_stacks, bool internal_format) {
1728 // this function is only used by debug.cpp
1729 print_on(tty, print_stacks, internal_format, false /* no concurrent lock printed */, false /* simple format */);
1730 }
1731 static void print_on_error(outputStream* st, Thread* current, char* buf, int buflen);
1732 static void print_on_error(Thread* this_thread, outputStream* st, Thread* current, char* buf,
1733 int buflen, bool* found_current);
1734 static void print_threads_compiling(outputStream* st, char* buf, int buflen, bool short_form = false);
1735
1736 // Get Java threads that are waiting to enter a monitor.
1737 static GrowableArray<JavaThread*>* get_pending_threads(ThreadsList * t_list,
1738 int count, address monitor);
1739
1740 // Get owning Java thread from the monitor's owner field.
1741 static JavaThread *owning_thread_from_monitor_owner(ThreadsList * t_list,
1742 address owner);
1743
1744 // Number of threads on the active threads list
1745 static int number_of_threads() { return _number_of_threads; }
1746 // Number of non-daemon threads on the active threads list
1747 static int number_of_non_daemon_threads() { return _number_of_non_daemon_threads; }
1748
1749 // Deoptimizes all frames tied to marked nmethods
1750 static void deoptimized_wrt_marked_nmethods();
1751
1752 struct Test; // For private gtest access.
1753 };
1754
1755 class UnlockFlagSaver {
1756 private:
1757 JavaThread* _thread;
1758 bool _do_not_unlock;
1759 public:
1760 UnlockFlagSaver(JavaThread* t) {
1761 _thread = t;
1762 _do_not_unlock = t->do_not_unlock_if_synchronized();
1763 t->set_do_not_unlock_if_synchronized(false);
1764 }
1765 ~UnlockFlagSaver() {
1766 _thread->set_do_not_unlock_if_synchronized(_do_not_unlock);
1767 }
1768 };
1769
1770 #endif // SHARE_RUNTIME_THREAD_HPP