1 /*
2 * Copyright (c) 1997, 2022, 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 // - WatcherThread
103 // - JfrThreadSampler
104 // - LogAsyncWriter
105 //
106 // All Thread subclasses must be either JavaThread or NonJavaThread.
107 // This means !t->is_Java_thread() iff t is a NonJavaThread, or t is
108 // a partially constructed/destroyed Thread.
109
110 // Thread execution sequence and actions:
111 // All threads:
112 // - thread_native_entry // per-OS native entry point
113 // - stack initialization
114 // - other OS-level initialization (signal masks etc)
115 // - handshake with creating thread (if not started suspended)
116 // - this->call_run() // common shared entry point
117 // - shared common initialization
118 // - this->pre_run() // virtual per-thread-type initialization
119 // - this->run() // virtual per-thread-type "main" logic
120 // - shared common tear-down
121 // - this->post_run() // virtual per-thread-type tear-down
122 // - // 'this' no longer referenceable
123 // - OS-level tear-down (minimal)
124 // - final logging
125 //
126 // For JavaThread:
127 // - this->run() // virtual but not normally overridden
128 // - this->thread_main_inner() // extra call level to ensure correct stack calculations
129 // - this->entry_point() // set differently for each kind of JavaThread
130
131 class Thread: public ThreadShadow {
132 friend class VMStructs;
133 friend class JVMCIVMStructs;
134 private:
135
136 #ifndef USE_LIBRARY_BASED_TLS_ONLY
137 // Current thread is maintained as a thread-local variable
138 static THREAD_LOCAL Thread* _thr_current;
139 #endif
140
141 // Thread local data area available to the GC. The internal
142 // structure and contents of this data area is GC-specific.
143 // Only GC and GC barrier code should access this data area.
144 GCThreadLocalData _gc_data;
145
146 public:
147 static ByteSize gc_data_offset() {
148 return byte_offset_of(Thread, _gc_data);
149 }
150
151 template <typename T> T* gc_data() {
152 STATIC_ASSERT(sizeof(T) <= sizeof(_gc_data));
153 return reinterpret_cast<T*>(&_gc_data);
154 }
155
156 // Exception handling
157 // (Note: _pending_exception and friends are in ThreadShadow)
158 //oop _pending_exception; // pending exception for current thread
159 // const char* _exception_file; // file information for exception (debugging only)
160 // int _exception_line; // line information for exception (debugging only)
161 protected:
162
163 DEBUG_ONLY(static Thread* _starting_thread;)
164
165 // JavaThread lifecycle support:
166 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
167 friend class ScanHazardPtrGatherProtectedThreadsClosure; // for cmpxchg_threads_hazard_ptr(), get_threads_hazard_ptr(), is_hazard_ptr_tagged() access
168 friend class ScanHazardPtrGatherThreadsListClosure; // for get_threads_hazard_ptr(), untag_hazard_ptr() access
169 friend class ScanHazardPtrPrintMatchingThreadsClosure; // for get_threads_hazard_ptr(), is_hazard_ptr_tagged() access
170 friend class ThreadsSMRSupport; // for _nested_threads_hazard_ptr_cnt, _threads_hazard_ptr, _threads_list_ptr access
171 friend class ThreadsListHandleTest; // for _nested_threads_hazard_ptr_cnt, _threads_hazard_ptr, _threads_list_ptr access
172 friend class ValidateHazardPtrsClosure; // for get_threads_hazard_ptr(), untag_hazard_ptr() access
173
174 ThreadsList* volatile _threads_hazard_ptr;
175 SafeThreadsListPtr* _threads_list_ptr;
176 ThreadsList* cmpxchg_threads_hazard_ptr(ThreadsList* exchange_value, ThreadsList* compare_value);
177 ThreadsList* get_threads_hazard_ptr() const;
178 void set_threads_hazard_ptr(ThreadsList* new_list);
179 static bool is_hazard_ptr_tagged(ThreadsList* list) {
180 return (intptr_t(list) & intptr_t(1)) == intptr_t(1);
181 }
182 static ThreadsList* tag_hazard_ptr(ThreadsList* list) {
183 return (ThreadsList*)(intptr_t(list) | intptr_t(1));
184 }
185 static ThreadsList* untag_hazard_ptr(ThreadsList* list) {
186 return (ThreadsList*)(intptr_t(list) & ~intptr_t(1));
187 }
188 // This field is enabled via -XX:+EnableThreadSMRStatistics:
189 uint _nested_threads_hazard_ptr_cnt;
190 void dec_nested_threads_hazard_ptr_cnt() {
191 assert(_nested_threads_hazard_ptr_cnt != 0, "mismatched {dec,inc}_nested_threads_hazard_ptr_cnt()");
192 _nested_threads_hazard_ptr_cnt--;
193 }
194 void inc_nested_threads_hazard_ptr_cnt() {
195 _nested_threads_hazard_ptr_cnt++;
196 }
197 uint nested_threads_hazard_ptr_cnt() {
198 return _nested_threads_hazard_ptr_cnt;
199 }
200
201 public:
202 // Is the target JavaThread protected by the calling Thread or by some other
203 // mechanism?
204 static bool is_JavaThread_protected(const JavaThread* target);
205 // Is the target JavaThread protected by a ThreadsListHandle (TLH) associated
206 // with the calling Thread?
207 static bool is_JavaThread_protected_by_TLH(const JavaThread* target);
208
209 void* operator new(size_t size) throw() { return allocate(size, true); }
210 void* operator new(size_t size, const std::nothrow_t& nothrow_constant) throw() {
211 return allocate(size, false); }
212 void operator delete(void* p);
213
214 protected:
215 static void* allocate(size_t size, bool throw_excpt, MEMFLAGS flags = mtThread);
216
217 private:
218 DEBUG_ONLY(bool _suspendible_thread;)
219
220 public:
221 // Determines if a heap allocation failure will be retried
222 // (e.g., by deoptimizing and re-executing in the interpreter).
223 // In this case, the failed allocation must raise
224 // Universe::out_of_memory_error_retry() and omit side effects
225 // such as JVMTI events and handling -XX:+HeapDumpOnOutOfMemoryError
226 // and -XX:OnOutOfMemoryError.
227 virtual bool in_retryable_allocation() const { return false; }
228
229 #ifdef ASSERT
230 void set_suspendible_thread() {
231 _suspendible_thread = true;
232 }
233
234 void clear_suspendible_thread() {
235 _suspendible_thread = false;
236 }
237
238 bool is_suspendible_thread() { return _suspendible_thread; }
239 #endif
240
241 private:
242 // Point to the last handle mark
243 HandleMark* _last_handle_mark;
244
245 // Claim value for parallel iteration over threads.
246 uintx _threads_do_token;
247
248 // Support for GlobalCounter
249 private:
250 volatile uintx _rcu_counter;
251 public:
252 volatile uintx* get_rcu_counter() {
253 return &_rcu_counter;
254 }
255
256 public:
257 void set_last_handle_mark(HandleMark* mark) { _last_handle_mark = mark; }
258 HandleMark* last_handle_mark() const { return _last_handle_mark; }
259 private:
260
261 #ifdef ASSERT
262 ICRefillVerifier* _missed_ic_stub_refill_verifier;
263
264 public:
265 ICRefillVerifier* missed_ic_stub_refill_verifier() {
266 return _missed_ic_stub_refill_verifier;
267 }
268
269 void set_missed_ic_stub_refill_verifier(ICRefillVerifier* verifier) {
270 _missed_ic_stub_refill_verifier = verifier;
271 }
272 #endif // ASSERT
273
274 private:
275 // Used by SkipGCALot class.
276 NOT_PRODUCT(bool _skip_gcalot;) // Should we elide gc-a-lot?
277
278 friend class GCLocker;
279
280 private:
281 ThreadLocalAllocBuffer _tlab; // Thread-local eden
282 jlong _allocated_bytes; // Cumulative number of bytes allocated on
283 // the Java heap
284 ThreadHeapSampler _heap_sampler; // For use when sampling the memory.
285
286 ThreadStatisticalInfo _statistical_info; // Statistics about the thread
287
288 JFR_ONLY(DEFINE_THREAD_LOCAL_FIELD_JFR;) // Thread-local data for jfr
289
290 JvmtiRawMonitor* _current_pending_raw_monitor; // JvmtiRawMonitor this thread
291 // is waiting to lock
292 public:
293 // Constructor
294 Thread();
295 virtual ~Thread() = 0; // Thread is abstract.
296
297 // Manage Thread::current()
298 void initialize_thread_current();
299 static void clear_thread_current(); // TLS cleanup needed before threads terminate
300
301 protected:
302 // To be implemented by children.
303 virtual void run() = 0;
304 virtual void pre_run() = 0;
305 virtual void post_run() = 0; // Note: Thread must not be deleted prior to calling this!
306
307 #ifdef ASSERT
308 enum RunState {
309 PRE_CALL_RUN,
310 CALL_RUN,
311 PRE_RUN,
312 RUN,
313 POST_RUN
314 // POST_CALL_RUN - can't define this one as 'this' may be deleted when we want to set it
315 };
316 RunState _run_state; // for lifecycle checks
317 #endif
318
319
320 public:
321 // invokes <ChildThreadClass>::run(), with common preparations and cleanups.
322 void call_run();
323
324 // Testers
325 virtual bool is_VM_thread() const { return false; }
326 virtual bool is_Java_thread() const { return false; }
327 virtual bool is_Compiler_thread() const { return false; }
328 virtual bool is_Code_cache_sweeper_thread() const { return false; }
329 virtual bool is_service_thread() const { return false; }
330 virtual bool is_monitor_deflation_thread() const { return false; }
331 virtual bool is_hidden_from_external_view() const { return false; }
332 virtual bool is_jvmti_agent_thread() const { return false; }
333 virtual bool is_Watcher_thread() const { return false; }
334 virtual bool is_ConcurrentGC_thread() const { return false; }
335 virtual bool is_Named_thread() const { return false; }
336 virtual bool is_Worker_thread() const { return false; }
337 virtual bool is_JfrSampler_thread() const { return false; }
338
339 // Can this thread make Java upcalls
340 virtual bool can_call_java() const { return false; }
341
342 // Is this a JavaThread that is on the VM's current ThreadsList?
343 // If so it must participate in the safepoint protocol.
344 virtual bool is_active_Java_thread() const { return false; }
345
346 // All threads are given names. For singleton subclasses we can
347 // just hard-wire the known name of the instance. JavaThreads and
348 // NamedThreads support multiple named instances, and dynamic
349 // changing of the name of an instance.
350 virtual const char* name() const { return "Unknown thread"; }
351
352 // A thread's type name is also made available for debugging
353 // and logging.
354 virtual const char* type_name() const { return "Thread"; }
355
356 // Returns the current thread (ASSERTS if NULL)
357 static inline Thread* current();
358 // Returns the current thread, or NULL if not attached
359 static inline Thread* current_or_null();
360 // Returns the current thread, or NULL if not attached, and is
361 // safe for use from signal-handlers
362 static inline Thread* current_or_null_safe();
363
364 // Common thread operations
365 #ifdef ASSERT
366 static void check_for_dangling_thread_pointer(Thread *thread);
367 #endif
368 static void set_priority(Thread* thread, ThreadPriority priority);
369 static ThreadPriority get_priority(const Thread* const thread);
370 static void start(Thread* thread);
371
372 void set_native_thread_name(const char *name) {
373 assert(Thread::current() == this, "set_native_thread_name can only be called on the current thread");
374 os::set_native_thread_name(name);
375 }
376
377 // Support for Unhandled Oop detection
378 // Add the field for both, fastdebug and debug, builds to keep
379 // Thread's fields layout the same.
380 // Note: CHECK_UNHANDLED_OOPS is defined only for fastdebug build.
381 #ifdef CHECK_UNHANDLED_OOPS
382 private:
383 UnhandledOops* _unhandled_oops;
384 #elif defined(ASSERT)
385 private:
386 void* _unhandled_oops;
387 #endif
388 #ifdef CHECK_UNHANDLED_OOPS
389 public:
390 UnhandledOops* unhandled_oops() { return _unhandled_oops; }
391 // Mark oop safe for gc. It may be stack allocated but won't move.
392 void allow_unhandled_oop(oop *op) {
393 if (CheckUnhandledOops) unhandled_oops()->allow_unhandled_oop(op);
394 }
395 // Clear oops at safepoint so crashes point to unhandled oop violator
396 void clear_unhandled_oops() {
397 if (CheckUnhandledOops) unhandled_oops()->clear_unhandled_oops();
398 }
399 #endif // CHECK_UNHANDLED_OOPS
400
401 public:
402 #ifndef PRODUCT
403 bool skip_gcalot() { return _skip_gcalot; }
404 void set_skip_gcalot(bool v) { _skip_gcalot = v; }
405 #endif
406
407 // Resource area
408 ResourceArea* resource_area() const { return _resource_area; }
409 void set_resource_area(ResourceArea* area) { _resource_area = area; }
410
411 OSThread* osthread() const { return _osthread; }
412 void set_osthread(OSThread* thread) { _osthread = thread; }
413
414 // Internal handle support
415 HandleArea* handle_area() const { return _handle_area; }
416 void set_handle_area(HandleArea* area) { _handle_area = area; }
417
418 GrowableArray<Metadata*>* metadata_handles() const { return _metadata_handles; }
419 void set_metadata_handles(GrowableArray<Metadata*>* handles){ _metadata_handles = handles; }
420
421 // Thread-Local Allocation Buffer (TLAB) support
422 ThreadLocalAllocBuffer& tlab() { return _tlab; }
423 void initialize_tlab();
424
425 jlong allocated_bytes() { return _allocated_bytes; }
426 void set_allocated_bytes(jlong value) { _allocated_bytes = value; }
427 void incr_allocated_bytes(jlong size) { _allocated_bytes += size; }
428 inline jlong cooked_allocated_bytes();
429
430 ThreadHeapSampler& heap_sampler() { return _heap_sampler; }
431
432 ThreadStatisticalInfo& statistical_info() { return _statistical_info; }
433
434 JFR_ONLY(DEFINE_THREAD_LOCAL_ACCESSOR_JFR;)
435
436 // For tracking the Jvmti raw monitor the thread is pending on.
437 JvmtiRawMonitor* current_pending_raw_monitor() {
438 return _current_pending_raw_monitor;
439 }
440 void set_current_pending_raw_monitor(JvmtiRawMonitor* monitor) {
441 _current_pending_raw_monitor = monitor;
442 }
443
444 // GC support
445 // Apply "f->do_oop" to all root oops in "this".
446 // Used by JavaThread::oops_do.
447 // Apply "cf->do_code_blob" (if !NULL) to all code blobs active in frames
448 virtual void oops_do_no_frames(OopClosure* f, CodeBlobClosure* cf);
449 virtual void oops_do_frames(OopClosure* f, CodeBlobClosure* cf) {}
450 void oops_do(OopClosure* f, CodeBlobClosure* cf);
451
452 // Handles the parallel case for claim_threads_do.
453 private:
454 bool claim_par_threads_do(uintx claim_token);
455 public:
456 // Requires that "claim_token" is that of the current iteration.
457 // If "is_par" is false, sets the token of "this" to
458 // "claim_token", and returns "true". If "is_par" is true,
459 // uses an atomic instruction to set the current thread's token to
460 // "claim_token", if it is not already. Returns "true" iff the
461 // calling thread does the update, this indicates that the calling thread
462 // has claimed the thread in the current iteration.
463 bool claim_threads_do(bool is_par, uintx claim_token) {
464 if (!is_par) {
465 _threads_do_token = claim_token;
466 return true;
467 } else {
468 return claim_par_threads_do(claim_token);
469 }
470 }
471
472 uintx threads_do_token() const { return _threads_do_token; }
473
474 // jvmtiRedefineClasses support
475 void metadata_handles_do(void f(Metadata*));
476
477 private:
478 // Check if address is within the given range of this thread's
479 // stack: stack_base() > adr >/>= limit
480 // The check is inclusive of limit if passed true, else exclusive.
481 bool is_in_stack_range(address adr, address limit, bool inclusive) const {
482 assert(stack_base() > limit && limit >= stack_end(), "limit is outside of stack");
483 return stack_base() > adr && (inclusive ? adr >= limit : adr > limit);
484 }
485
486 public:
487 // Used by fast lock support
488 virtual bool is_lock_owned(address adr) const;
489
490 // Check if address is within the given range of this thread's
491 // stack: stack_base() > adr >= limit
492 bool is_in_stack_range_incl(address adr, address limit) const {
493 return is_in_stack_range(adr, limit, true);
494 }
495
496 // Check if address is within the given range of this thread's
497 // stack: stack_base() > adr > limit
498 bool is_in_stack_range_excl(address adr, address limit) const {
499 return is_in_stack_range(adr, limit, false);
500 }
501
502 // Check if address is in the stack mapped to this thread. Used mainly in
503 // error reporting (so has to include guard zone) and frame printing.
504 // Expects _stack_base to be initialized - checked with assert.
505 bool is_in_full_stack_checked(address adr) const {
506 return is_in_stack_range_incl(adr, stack_end());
507 }
508
509 // Like is_in_full_stack_checked but without the assertions as this
510 // may be called in a thread before _stack_base is initialized.
511 bool is_in_full_stack(address adr) const {
512 address stack_end = _stack_base - _stack_size;
513 return _stack_base > adr && adr >= stack_end;
514 }
515
516 // Check if address is in the live stack of this thread (not just for locks).
517 // Warning: can only be called by the current thread on itself.
518 bool is_in_live_stack(address adr) const {
519 assert(Thread::current() == this, "is_in_live_stack can only be called from current thread");
520 return is_in_stack_range_incl(adr, os::current_stack_pointer());
521 }
522
523 // Sets this thread as starting thread. Returns failure if thread
524 // creation fails due to lack of memory, too many threads etc.
525 bool set_as_starting_thread();
526
527 protected:
528 // OS data associated with the thread
529 OSThread* _osthread; // Platform-specific thread information
530
531 // Thread local resource area for temporary allocation within the VM
532 ResourceArea* _resource_area;
533
534 DEBUG_ONLY(ResourceMark* _current_resource_mark;)
535
536 // Thread local handle area for allocation of handles within the VM
537 HandleArea* _handle_area;
538 GrowableArray<Metadata*>* _metadata_handles;
539
540 // Support for stack overflow handling, get_thread, etc.
541 address _stack_base;
542 size_t _stack_size;
543 int _lgrp_id;
544
545 public:
546 // Stack overflow support
547 address stack_base() const { assert(_stack_base != NULL,"Sanity check"); return _stack_base; }
548 void set_stack_base(address base) { _stack_base = base; }
549 size_t stack_size() const { return _stack_size; }
550 void set_stack_size(size_t size) { _stack_size = size; }
551 address stack_end() const { return stack_base() - stack_size(); }
552 void record_stack_base_and_size();
553 void register_thread_stack_with_NMT();
554 void unregister_thread_stack_with_NMT();
555
556 int lgrp_id() const { return _lgrp_id; }
557 void set_lgrp_id(int value) { _lgrp_id = value; }
558
559 // Printing
560 void print_on(outputStream* st, bool print_extended_info) const;
561 virtual void print_on(outputStream* st) const { print_on(st, false); }
562 void print() const;
563 virtual void print_on_error(outputStream* st, char* buf, int buflen) const;
564 // Basic, non-virtual, printing support that is simple and always safe.
565 void print_value_on(outputStream* st) const;
566
567 // Debug-only code
568 #ifdef ASSERT
569 private:
570 // Deadlock detection support for Mutex locks. List of locks own by thread.
571 Mutex* _owned_locks;
572 // Mutex::set_owner_implementation is the only place where _owned_locks is modified,
573 // thus the friendship
574 friend class Mutex;
575 friend class Monitor;
576
577 public:
578 void print_owned_locks_on(outputStream* st) const;
579 void print_owned_locks() const { print_owned_locks_on(tty); }
580 Mutex* owned_locks() const { return _owned_locks; }
581 bool owns_locks() const { return owned_locks() != NULL; }
582
583 // Deadlock detection
584 ResourceMark* current_resource_mark() { return _current_resource_mark; }
585 void set_current_resource_mark(ResourceMark* rm) { _current_resource_mark = rm; }
586 #endif // ASSERT
587
588 private:
589 volatile int _jvmti_env_iteration_count;
590
591 public:
592 void entering_jvmti_env_iteration() { ++_jvmti_env_iteration_count; }
593 void leaving_jvmti_env_iteration() { --_jvmti_env_iteration_count; }
594 bool is_inside_jvmti_env_iteration() { return _jvmti_env_iteration_count > 0; }
595
596 // Code generation
597 static ByteSize exception_file_offset() { return byte_offset_of(Thread, _exception_file); }
598 static ByteSize exception_line_offset() { return byte_offset_of(Thread, _exception_line); }
599
600 static ByteSize stack_base_offset() { return byte_offset_of(Thread, _stack_base); }
601 static ByteSize stack_size_offset() { return byte_offset_of(Thread, _stack_size); }
602
603 static ByteSize tlab_start_offset() { return byte_offset_of(Thread, _tlab) + ThreadLocalAllocBuffer::start_offset(); }
604 static ByteSize tlab_end_offset() { return byte_offset_of(Thread, _tlab) + ThreadLocalAllocBuffer::end_offset(); }
605 static ByteSize tlab_top_offset() { return byte_offset_of(Thread, _tlab) + ThreadLocalAllocBuffer::top_offset(); }
606 static ByteSize tlab_pf_top_offset() { return byte_offset_of(Thread, _tlab) + ThreadLocalAllocBuffer::pf_top_offset(); }
607
608 static ByteSize allocated_bytes_offset() { return byte_offset_of(Thread, _allocated_bytes); }
609
610 JFR_ONLY(DEFINE_THREAD_LOCAL_OFFSET_JFR;)
611
612 public:
613 ParkEvent * volatile _ParkEvent; // for Object monitors, JVMTI raw monitors,
614 // and ObjectSynchronizer::read_stable_mark
615
616 // Termination indicator used by the signal handler.
617 // _ParkEvent is just a convenient field we can NULL out after setting the JavaThread termination state
618 // (which can't itself be read from the signal handler if a signal hits during the Thread destructor).
619 bool has_terminated() { return Atomic::load(&_ParkEvent) == NULL; };
620
621 jint _hashStateW; // Marsaglia Shift-XOR thread-local RNG
622 jint _hashStateX; // thread-specific hashCode generator state
623 jint _hashStateY;
624 jint _hashStateZ;
625
626 // Low-level leaf-lock primitives used to implement synchronization.
627 // Not for general synchronization use.
628 static void SpinAcquire(volatile int * Lock, const char * Name);
629 static void SpinRelease(volatile int * Lock);
630
631 #if defined(__APPLE__) && defined(AARCH64)
632 private:
633 DEBUG_ONLY(bool _wx_init);
634 WXMode _wx_state;
635 public:
636 void init_wx();
637 WXMode enable_wx(WXMode new_state);
638
639 void assert_wx_state(WXMode expected) {
640 assert(_wx_state == expected, "wrong state");
641 }
642 #endif // __APPLE__ && AARCH64
643 };
644
645 // Inline implementation of Thread::current()
646 inline Thread* Thread::current() {
647 Thread* current = current_or_null();
648 assert(current != NULL, "Thread::current() called on detached thread");
649 return current;
650 }
651
652 inline Thread* Thread::current_or_null() {
653 #ifndef USE_LIBRARY_BASED_TLS_ONLY
654 return _thr_current;
655 #else
656 if (ThreadLocalStorage::is_initialized()) {
657 return ThreadLocalStorage::thread();
658 }
659 return NULL;
660 #endif
661 }
662
663 inline Thread* Thread::current_or_null_safe() {
664 if (ThreadLocalStorage::is_initialized()) {
665 return ThreadLocalStorage::thread();
666 }
667 return NULL;
668 }
669
670 class CompilerThread;
671
672 typedef void (*ThreadFunction)(JavaThread*, TRAPS);
673
674 class JavaThread: public Thread {
675 friend class VMStructs;
676 friend class JVMCIVMStructs;
677 friend class WhiteBox;
678 friend class VTBuffer;
679 friend class ThreadsSMRSupport; // to access _threadObj for exiting_threads_oops_do
680 friend class HandshakeState;
681 private:
682 bool _on_thread_list; // Is set when this JavaThread is added to the Threads list
683 OopHandle _threadObj; // The Java level thread object
684
685 #ifdef ASSERT
686 private:
687 int _java_call_counter;
688
689 public:
690 int java_call_counter() { return _java_call_counter; }
691 void inc_java_call_counter() { _java_call_counter++; }
692 void dec_java_call_counter() {
693 assert(_java_call_counter > 0, "Invalid nesting of JavaCallWrapper");
694 _java_call_counter--;
695 }
696 private: // restore original namespace restriction
697 #endif // ifdef ASSERT
698
699 JavaFrameAnchor _anchor; // Encapsulation of current java frame and it state
700
701 ThreadFunction _entry_point;
702
703 JNIEnv _jni_environment;
704
705 // Deopt support
706 DeoptResourceMark* _deopt_mark; // Holds special ResourceMark for deoptimization
707
708 CompiledMethod* _deopt_nmethod; // CompiledMethod that is currently being deoptimized
709 vframeArray* _vframe_array_head; // Holds the heap of the active vframeArrays
710 vframeArray* _vframe_array_last; // Holds last vFrameArray we popped
711 // Holds updates by JVMTI agents for compiled frames that cannot be performed immediately. They
712 // will be carried out as soon as possible which, in most cases, is just before deoptimization of
713 // the frame, when control returns to it.
714 JvmtiDeferredUpdates* _jvmti_deferred_updates;
715
716 // Handshake value for fixing 6243940. We need a place for the i2c
717 // adapter to store the callee Method*. This value is NEVER live
718 // across a gc point so it does NOT have to be gc'd
719 // The handshake is open ended since we can't be certain that it will
720 // be NULLed. This is because we rarely ever see the race and end up
721 // in handle_wrong_method which is the backend of the handshake. See
722 // code in i2c adapters and handle_wrong_method.
723
724 Method* _callee_target;
725
726 // Used to pass back results to the interpreter or generated code running Java code.
727 oop _vm_result; // oop result is GC-preserved
728 Metadata* _vm_result_2; // non-oop result
729 oop _return_buffered_value; // buffered value being returned
730
731 // See ReduceInitialCardMarks: this holds the precise space interval of
732 // the most recent slow path allocation for which compiled code has
733 // elided card-marks for performance along the fast-path.
734 MemRegion _deferred_card_mark;
735
736 ObjectMonitor* volatile _current_pending_monitor; // ObjectMonitor this thread is waiting to lock
737 bool _current_pending_monitor_is_from_java; // locking is from Java code
738 ObjectMonitor* volatile _current_waiting_monitor; // ObjectMonitor on which this thread called Object.wait()
739
740 // Active_handles points to a block of handles
741 JNIHandleBlock* _active_handles;
742
743 // One-element thread local free list
744 JNIHandleBlock* _free_handle_block;
745
746 public:
747 volatile intptr_t _Stalled;
748
749 // For tracking the heavyweight monitor the thread is pending on.
750 ObjectMonitor* current_pending_monitor() {
751 // Use Atomic::load() to prevent data race between concurrent modification and
752 // concurrent readers, e.g. ThreadService::get_current_contended_monitor().
753 // Especially, reloading pointer from thread after NULL check must be prevented.
754 return Atomic::load(&_current_pending_monitor);
755 }
756 void set_current_pending_monitor(ObjectMonitor* monitor) {
757 Atomic::store(&_current_pending_monitor, monitor);
758 }
759 void set_current_pending_monitor_is_from_java(bool from_java) {
760 _current_pending_monitor_is_from_java = from_java;
761 }
762 bool current_pending_monitor_is_from_java() {
763 return _current_pending_monitor_is_from_java;
764 }
765 ObjectMonitor* current_waiting_monitor() {
766 // See the comment in current_pending_monitor() above.
767 return Atomic::load(&_current_waiting_monitor);
768 }
769 void set_current_waiting_monitor(ObjectMonitor* monitor) {
770 Atomic::store(&_current_waiting_monitor, monitor);
771 }
772
773 // JNI handle support
774 JNIHandleBlock* active_handles() const { return _active_handles; }
775 void set_active_handles(JNIHandleBlock* block) { _active_handles = block; }
776 JNIHandleBlock* free_handle_block() const { return _free_handle_block; }
777 void set_free_handle_block(JNIHandleBlock* block) { _free_handle_block = block; }
778
779 void push_jni_handle_block();
780 void pop_jni_handle_block();
781
782 private:
783 MonitorChunk* _monitor_chunks; // Contains the off stack monitors
784 // allocated during deoptimization
785 // and by JNI_MonitorEnter/Exit
786
787 enum SuspendFlags {
788 // NOTE: avoid using the sign-bit as cc generates different test code
789 // when the sign-bit is used, and sometimes incorrectly - see CR 6398077
790 _has_async_exception = 0x00000001U, // there is a pending async exception
791 _async_delivery_disabled = 0x00000002U, // async exception delivery is disabled
792 _trace_flag = 0x00000004U, // call tracing backend
793 _obj_deopt = 0x00000008U // suspend for object reallocation and relocking for JVMTI agent
794 };
795
796 // various suspension related flags - atomically updated
797 // overloaded with async exceptions so that we do a single check when transitioning from native->Java
798 volatile uint32_t _suspend_flags;
799
800 inline void set_suspend_flag(SuspendFlags f);
801 inline void clear_suspend_flag(SuspendFlags f);
802
803 public:
804 inline void set_trace_flag();
805 inline void clear_trace_flag();
806 inline void set_obj_deopt_flag();
807 inline void clear_obj_deopt_flag();
808 bool is_trace_suspend() { return (_suspend_flags & _trace_flag) != 0; }
809 bool is_obj_deopt_suspend() { return (_suspend_flags & _obj_deopt) != 0; }
810
811 // Asynchronous exceptions support
812 private:
813 oop _pending_async_exception;
814 #ifdef ASSERT
815 bool _is_unsafe_access_error;
816 #endif
817
818 inline bool clear_async_exception_condition();
819 public:
820 bool has_async_exception_condition() {
821 return (_suspend_flags & _has_async_exception) != 0 &&
822 (_suspend_flags & _async_delivery_disabled) == 0;
823 }
824 inline void set_pending_async_exception(oop e);
825 inline void set_pending_unsafe_access_error();
826 static void send_async_exception(JavaThread* jt, oop java_throwable);
827 void send_thread_stop(oop throwable);
828 void check_and_handle_async_exceptions();
829
830 class NoAsyncExceptionDeliveryMark : public StackObj {
831 friend JavaThread;
832 JavaThread *_target;
833 inline NoAsyncExceptionDeliveryMark(JavaThread *t);
834 inline ~NoAsyncExceptionDeliveryMark();
835 };
836
837 // Safepoint support
838 public: // Expose _thread_state for SafeFetchInt()
839 volatile JavaThreadState _thread_state;
840 private:
841 SafepointMechanism::ThreadData _poll_data;
842 ThreadSafepointState* _safepoint_state; // Holds information about a thread during a safepoint
843 address _saved_exception_pc; // Saved pc of instruction where last implicit exception happened
844 NOT_PRODUCT(bool _requires_cross_modify_fence;) // State used by VerifyCrossModifyFence
845 #ifdef ASSERT
846 // Debug support for checking if code allows safepoints or not.
847 // Safepoints in the VM can happen because of allocation, invoking a VM operation, or blocking on
848 // mutex, or blocking on an object synchronizer (Java locking).
849 // If _no_safepoint_count is non-zero, then an assertion failure will happen in any of
850 // the above cases. The class NoSafepointVerifier is used to set this counter.
851 int _no_safepoint_count; // If 0, thread allow a safepoint to happen
852
853 public:
854 void inc_no_safepoint_count() { _no_safepoint_count++; }
855 void dec_no_safepoint_count() { _no_safepoint_count--; }
856 #endif // ASSERT
857 public:
858 // These functions check conditions before possibly going to a safepoint.
859 // including NoSafepointVerifier.
860 void check_for_valid_safepoint_state() NOT_DEBUG_RETURN;
861 void check_possible_safepoint() NOT_DEBUG_RETURN;
862
863 #ifdef ASSERT
864 private:
865 volatile uint64_t _visited_for_critical_count;
866
867 public:
868 void set_visited_for_critical_count(uint64_t safepoint_id) {
869 assert(_visited_for_critical_count == 0, "Must be reset before set");
870 assert((safepoint_id & 0x1) == 1, "Must be odd");
871 _visited_for_critical_count = safepoint_id;
872 }
873 void reset_visited_for_critical_count(uint64_t safepoint_id) {
874 assert(_visited_for_critical_count == safepoint_id, "Was not visited");
875 _visited_for_critical_count = 0;
876 }
877 bool was_visited_for_critical_count(uint64_t safepoint_id) const {
878 return _visited_for_critical_count == safepoint_id;
879 }
880 #endif // ASSERT
881
882 // JavaThread termination support
883 public:
884 enum TerminatedTypes {
885 _not_terminated = 0xDEAD - 2,
886 _thread_exiting, // JavaThread::exit() has been called for this thread
887 _thread_terminated, // JavaThread is removed from thread list
888 _vm_exited // JavaThread is still executing native code, but VM is terminated
889 // only VM_Exit can set _vm_exited
890 };
891
892 private:
893 // In general a JavaThread's _terminated field transitions as follows:
894 //
895 // _not_terminated => _thread_exiting => _thread_terminated
896 //
897 // _vm_exited is a special value to cover the case of a JavaThread
898 // executing native code after the VM itself is terminated.
899 volatile TerminatedTypes _terminated;
900
901 jint _in_deopt_handler; // count of deoptimization
902 // handlers thread is in
903 volatile bool _doing_unsafe_access; // Thread may fault due to unsafe access
904 bool _do_not_unlock_if_synchronized; // Do not unlock the receiver of a synchronized method (since it was
905 // never locked) when throwing an exception. Used by interpreter only.
906
907 // JNI attach states:
908 enum JNIAttachStates {
909 _not_attaching_via_jni = 1, // thread is not attaching via JNI
910 _attaching_via_jni, // thread is attaching via JNI
911 _attached_via_jni // thread has attached via JNI
912 };
913
914 // A regular JavaThread's _jni_attach_state is _not_attaching_via_jni.
915 // A native thread that is attaching via JNI starts with a value
916 // of _attaching_via_jni and transitions to _attached_via_jni.
917 volatile JNIAttachStates _jni_attach_state;
918
919
920 #if INCLUDE_JVMCI
921 // The _pending_* fields below are used to communicate extra information
922 // from an uncommon trap in JVMCI compiled code to the uncommon trap handler.
923
924 // Communicates the DeoptReason and DeoptAction of the uncommon trap
925 int _pending_deoptimization;
926
927 // Specifies whether the uncommon trap is to bci 0 of a synchronized method
928 // before the monitor has been acquired.
929 bool _pending_monitorenter;
930
931 // Specifies if the DeoptReason for the last uncommon trap was Reason_transfer_to_interpreter
932 bool _pending_transfer_to_interpreter;
933
934 // True if in a runtime call from compiled code that will deoptimize
935 // and re-execute a failed heap allocation in the interpreter.
936 bool _in_retryable_allocation;
937
938 // An id of a speculation that JVMCI compiled code can use to further describe and
939 // uniquely identify the speculative optimization guarded by an uncommon trap.
940 // See JVMCINMethodData::SPECULATION_LENGTH_BITS for further details.
941 jlong _pending_failed_speculation;
942
943 // These fields are mutually exclusive in terms of live ranges.
944 union {
945 // Communicates the pc at which the most recent implicit exception occurred
946 // from the signal handler to a deoptimization stub.
947 address _implicit_exception_pc;
948
949 // Communicates an alternative call target to an i2c stub from a JavaCall .
950 address _alternate_call_target;
951 } _jvmci;
952
953 // Support for high precision, thread sensitive counters in JVMCI compiled code.
954 jlong* _jvmci_counters;
955
956 // Fast thread locals for use by JVMCI
957 jlong _jvmci_reserved0;
958 jlong _jvmci_reserved1;
959 oop _jvmci_reserved_oop0;
960
961 public:
962 static jlong* _jvmci_old_thread_counters;
963 static void collect_counters(jlong* array, int length);
964
965 bool resize_counters(int current_size, int new_size);
966
967 static bool resize_all_jvmci_counters(int new_size);
968
969 void set_jvmci_reserved_oop0(oop value) {
970 _jvmci_reserved_oop0 = value;
971 }
972
973 oop get_jvmci_reserved_oop0() {
974 return _jvmci_reserved_oop0;
975 }
976
977 void set_jvmci_reserved0(jlong value) {
978 _jvmci_reserved0 = value;
979 }
980
981 jlong get_jvmci_reserved0() {
982 return _jvmci_reserved0;
983 }
984
985 void set_jvmci_reserved1(jlong value) {
986 _jvmci_reserved1 = value;
987 }
988
989 jlong get_jvmci_reserved1() {
990 return _jvmci_reserved1;
991 }
992
993 private:
994 #endif // INCLUDE_JVMCI
995
996 StackOverflow _stack_overflow_state;
997
998 // Compiler exception handling (NOTE: The _exception_oop is *NOT* the same as _pending_exception. It is
999 // used to temp. parsing values into and out of the runtime system during exception handling for compiled
1000 // code)
1001 volatile oop _exception_oop; // Exception thrown in compiled code
1002 volatile address _exception_pc; // PC where exception happened
1003 volatile address _exception_handler_pc; // PC for handler of exception
1004 volatile int _is_method_handle_return; // true (== 1) if the current exception PC is a MethodHandle call site.
1005
1006 private:
1007 // support for JNI critical regions
1008 jint _jni_active_critical; // count of entries into JNI critical region
1009
1010 // Checked JNI: function name requires exception check
1011 char* _pending_jni_exception_check_fn;
1012
1013 // For deadlock detection.
1014 int _depth_first_number;
1015
1016 // JVMTI PopFrame support
1017 // This is set to popframe_pending to signal that top Java frame should be popped immediately
1018 int _popframe_condition;
1019
1020 // If reallocation of scalar replaced objects fails, we throw OOM
1021 // and during exception propagation, pop the top
1022 // _frames_to_pop_failed_realloc frames, the ones that reference
1023 // failed reallocations.
1024 int _frames_to_pop_failed_realloc;
1025
1026 friend class VMThread;
1027 friend class ThreadWaitTransition;
1028 friend class VM_Exit;
1029
1030 // Stack watermark barriers.
1031 StackWatermarks _stack_watermarks;
1032
1033 public:
1034 inline StackWatermarks* stack_watermarks() { return &_stack_watermarks; }
1035
1036 public:
1037 // Constructor
1038 JavaThread(); // delegating constructor
1039 JavaThread(bool is_attaching_via_jni); // for main thread and JNI attached threads
1040 JavaThread(ThreadFunction entry_point, size_t stack_size = 0);
1041 ~JavaThread();
1042
1043 #ifdef ASSERT
1044 // verify this JavaThread hasn't be published in the Threads::list yet
1045 void verify_not_published();
1046 #endif // ASSERT
1047
1048 StackOverflow* stack_overflow_state() { return &_stack_overflow_state; }
1049
1050 //JNI functiontable getter/setter for JVMTI jni function table interception API.
1051 void set_jni_functions(struct JNINativeInterface_* functionTable) {
1052 _jni_environment.functions = functionTable;
1053 }
1054 struct JNINativeInterface_* get_jni_functions() {
1055 return (struct JNINativeInterface_ *)_jni_environment.functions;
1056 }
1057
1058 // This function is called at thread creation to allow
1059 // platform specific thread variables to be initialized.
1060 void cache_global_variables();
1061
1062 // Executes Shutdown.shutdown()
1063 void invoke_shutdown_hooks();
1064
1065 // Cleanup on thread exit
1066 enum ExitType {
1067 normal_exit,
1068 jni_detach
1069 };
1070 void exit(bool destroy_vm, ExitType exit_type = normal_exit);
1071
1072 void cleanup_failed_attach_current_thread(bool is_daemon);
1073
1074 // Testers
1075 virtual bool is_Java_thread() const { return true; }
1076 virtual bool can_call_java() const { return true; }
1077
1078 virtual bool is_active_Java_thread() const {
1079 return on_thread_list() && !is_terminated();
1080 }
1081
1082 // Thread oop. threadObj() can be NULL for initial JavaThread
1083 // (or for threads attached via JNI)
1084 oop threadObj() const;
1085 void set_threadObj(oop p);
1086
1087 // Prepare thread and add to priority queue. If a priority is
1088 // not specified, use the priority of the thread object. Threads_lock
1089 // must be held while this function is called.
1090 void prepare(jobject jni_thread, ThreadPriority prio=NoPriority);
1091
1092 void set_saved_exception_pc(address pc) { _saved_exception_pc = pc; }
1093 address saved_exception_pc() { return _saved_exception_pc; }
1094
1095 ThreadFunction entry_point() const { return _entry_point; }
1096
1097 // Allocates a new Java level thread object for this thread. thread_name may be NULL.
1098 void allocate_threadObj(Handle thread_group, const char* thread_name, bool daemon, TRAPS);
1099
1100 // Last frame anchor routines
1101
1102 JavaFrameAnchor* frame_anchor(void) { return &_anchor; }
1103
1104 // last_Java_sp
1105 bool has_last_Java_frame() const { return _anchor.has_last_Java_frame(); }
1106 intptr_t* last_Java_sp() const { return _anchor.last_Java_sp(); }
1107
1108 // last_Java_pc
1109
1110 address last_Java_pc(void) { return _anchor.last_Java_pc(); }
1111
1112 // Safepoint support
1113 inline JavaThreadState thread_state() const;
1114 inline void set_thread_state(JavaThreadState s);
1115 inline void set_thread_state_fence(JavaThreadState s); // fence after setting thread state
1116 inline ThreadSafepointState* safepoint_state() const;
1117 inline void set_safepoint_state(ThreadSafepointState* state);
1118 inline bool is_at_poll_safepoint();
1119
1120 // JavaThread termination and lifecycle support:
1121 void smr_delete();
1122 bool on_thread_list() const { return _on_thread_list; }
1123 void set_on_thread_list() { _on_thread_list = true; }
1124
1125 // thread has called JavaThread::exit() or is terminated
1126 bool is_exiting() const;
1127 // thread is terminated (no longer on the threads list); we compare
1128 // against the two non-terminated values so that a freed JavaThread
1129 // will also be considered terminated.
1130 bool check_is_terminated(TerminatedTypes l_terminated) const {
1131 return l_terminated != _not_terminated && l_terminated != _thread_exiting;
1132 }
1133 bool is_terminated() const;
1134 void set_terminated(TerminatedTypes t);
1135
1136 void block_if_vm_exited();
1137
1138 bool doing_unsafe_access() { return _doing_unsafe_access; }
1139 void set_doing_unsafe_access(bool val) { _doing_unsafe_access = val; }
1140
1141 bool do_not_unlock_if_synchronized() { return _do_not_unlock_if_synchronized; }
1142 void set_do_not_unlock_if_synchronized(bool val) { _do_not_unlock_if_synchronized = val; }
1143
1144 SafepointMechanism::ThreadData* poll_data() { return &_poll_data; }
1145
1146 void set_requires_cross_modify_fence(bool val) PRODUCT_RETURN NOT_PRODUCT({ _requires_cross_modify_fence = val; })
1147
1148 private:
1149 DEBUG_ONLY(void verify_frame_info();)
1150
1151 // Support for thread handshake operations
1152 HandshakeState _handshake;
1153 public:
1154 HandshakeState* handshake_state() { return &_handshake; }
1155
1156 // A JavaThread can always safely operate on it self and other threads
1157 // can do it safely if they are the active handshaker.
1158 bool is_handshake_safe_for(Thread* th) const {
1159 return _handshake.active_handshaker() == th || this == th;
1160 }
1161
1162 // Suspend/resume support for JavaThread
1163 bool java_suspend(); // higher-level suspension logic called by the public APIs
1164 bool java_resume(); // higher-level resume logic called by the public APIs
1165 bool is_suspended() { return _handshake.is_suspended(); }
1166
1167 // Check for async exception in addition to safepoint.
1168 static void check_special_condition_for_native_trans(JavaThread *thread);
1169
1170 // Synchronize with another thread that is deoptimizing objects of the
1171 // current thread, i.e. reverts optimizations based on escape analysis.
1172 void wait_for_object_deoptimization();
1173
1174 // these next two are also used for self-suspension and async exception support
1175 void handle_special_runtime_exit_condition(bool check_asyncs = true);
1176
1177 // Return true if JavaThread has an asynchronous condition or
1178 // if external suspension is requested.
1179 bool has_special_runtime_exit_condition() {
1180 return (_suspend_flags & (_has_async_exception | _obj_deopt JFR_ONLY(| _trace_flag))) != 0;
1181 }
1182
1183 // Fast-locking support
1184 bool is_lock_owned(address adr) const;
1185
1186 // Accessors for vframe array top
1187 // The linked list of vframe arrays are sorted on sp. This means when we
1188 // unpack the head must contain the vframe array to unpack.
1189 void set_vframe_array_head(vframeArray* value) { _vframe_array_head = value; }
1190 vframeArray* vframe_array_head() const { return _vframe_array_head; }
1191
1192 // Side structure for deferring update of java frame locals until deopt occurs
1193 JvmtiDeferredUpdates* deferred_updates() const { return _jvmti_deferred_updates; }
1194 void set_deferred_updates(JvmtiDeferredUpdates* du) { _jvmti_deferred_updates = du; }
1195
1196 // These only really exist to make debugging deopt problems simpler
1197
1198 void set_vframe_array_last(vframeArray* value) { _vframe_array_last = value; }
1199 vframeArray* vframe_array_last() const { return _vframe_array_last; }
1200
1201 // The special resourceMark used during deoptimization
1202
1203 void set_deopt_mark(DeoptResourceMark* value) { _deopt_mark = value; }
1204 DeoptResourceMark* deopt_mark(void) { return _deopt_mark; }
1205
1206 void set_deopt_compiled_method(CompiledMethod* nm) { _deopt_nmethod = nm; }
1207 CompiledMethod* deopt_compiled_method() { return _deopt_nmethod; }
1208
1209 Method* callee_target() const { return _callee_target; }
1210 void set_callee_target (Method* x) { _callee_target = x; }
1211
1212 // Oop results of vm runtime calls
1213 oop vm_result() const { return _vm_result; }
1214 void set_vm_result (oop x) { _vm_result = x; }
1215
1216 Metadata* vm_result_2() const { return _vm_result_2; }
1217 void set_vm_result_2 (Metadata* x) { _vm_result_2 = x; }
1218
1219 oop return_buffered_value() const { return _return_buffered_value; }
1220 void set_return_buffered_value(oop val) { _return_buffered_value = val; }
1221
1222 MemRegion deferred_card_mark() const { return _deferred_card_mark; }
1223 void set_deferred_card_mark(MemRegion mr) { _deferred_card_mark = mr; }
1224
1225 #if INCLUDE_JVMCI
1226 int pending_deoptimization() const { return _pending_deoptimization; }
1227 jlong pending_failed_speculation() const { return _pending_failed_speculation; }
1228 bool has_pending_monitorenter() const { return _pending_monitorenter; }
1229 void set_pending_monitorenter(bool b) { _pending_monitorenter = b; }
1230 void set_pending_deoptimization(int reason) { _pending_deoptimization = reason; }
1231 void set_pending_failed_speculation(jlong failed_speculation) { _pending_failed_speculation = failed_speculation; }
1232 void set_pending_transfer_to_interpreter(bool b) { _pending_transfer_to_interpreter = b; }
1233 void set_jvmci_alternate_call_target(address a) { assert(_jvmci._alternate_call_target == NULL, "must be"); _jvmci._alternate_call_target = a; }
1234 void set_jvmci_implicit_exception_pc(address a) { assert(_jvmci._implicit_exception_pc == NULL, "must be"); _jvmci._implicit_exception_pc = a; }
1235
1236 virtual bool in_retryable_allocation() const { return _in_retryable_allocation; }
1237 void set_in_retryable_allocation(bool b) { _in_retryable_allocation = b; }
1238 #endif // INCLUDE_JVMCI
1239
1240 // Exception handling for compiled methods
1241 oop exception_oop() const;
1242 address exception_pc() const { return _exception_pc; }
1243 address exception_handler_pc() const { return _exception_handler_pc; }
1244 bool is_method_handle_return() const { return _is_method_handle_return == 1; }
1245
1246 void set_exception_oop(oop o);
1247 void set_exception_pc(address a) { _exception_pc = a; }
1248 void set_exception_handler_pc(address a) { _exception_handler_pc = a; }
1249 void set_is_method_handle_return(bool value) { _is_method_handle_return = value ? 1 : 0; }
1250
1251 void clear_exception_oop_and_pc() {
1252 set_exception_oop(NULL);
1253 set_exception_pc(NULL);
1254 }
1255
1256 // Check if address is in the usable part of the stack (excludes protected
1257 // guard pages). Can be applied to any thread and is an approximation for
1258 // using is_in_live_stack when the query has to happen from another thread.
1259 bool is_in_usable_stack(address adr) const {
1260 return is_in_stack_range_incl(adr, _stack_overflow_state.stack_reserved_zone_base());
1261 }
1262
1263 // Misc. accessors/mutators
1264 void set_do_not_unlock(void) { _do_not_unlock_if_synchronized = true; }
1265 void clr_do_not_unlock(void) { _do_not_unlock_if_synchronized = false; }
1266 bool do_not_unlock(void) { return _do_not_unlock_if_synchronized; }
1267
1268 // For assembly stub generation
1269 static ByteSize threadObj_offset() { return byte_offset_of(JavaThread, _threadObj); }
1270 static ByteSize jni_environment_offset() { return byte_offset_of(JavaThread, _jni_environment); }
1271 static ByteSize pending_jni_exception_check_fn_offset() {
1272 return byte_offset_of(JavaThread, _pending_jni_exception_check_fn);
1273 }
1274 static ByteSize last_Java_sp_offset() {
1275 return byte_offset_of(JavaThread, _anchor) + JavaFrameAnchor::last_Java_sp_offset();
1276 }
1277 static ByteSize last_Java_pc_offset() {
1278 return byte_offset_of(JavaThread, _anchor) + JavaFrameAnchor::last_Java_pc_offset();
1279 }
1280 static ByteSize frame_anchor_offset() {
1281 return byte_offset_of(JavaThread, _anchor);
1282 }
1283 static ByteSize callee_target_offset() { return byte_offset_of(JavaThread, _callee_target); }
1284 static ByteSize vm_result_offset() { return byte_offset_of(JavaThread, _vm_result); }
1285 static ByteSize vm_result_2_offset() { return byte_offset_of(JavaThread, _vm_result_2); }
1286 static ByteSize return_buffered_value_offset() { return byte_offset_of(JavaThread, _return_buffered_value); }
1287 static ByteSize thread_state_offset() { return byte_offset_of(JavaThread, _thread_state); }
1288 static ByteSize polling_word_offset() { return byte_offset_of(JavaThread, _poll_data) + byte_offset_of(SafepointMechanism::ThreadData, _polling_word);}
1289 static ByteSize polling_page_offset() { return byte_offset_of(JavaThread, _poll_data) + byte_offset_of(SafepointMechanism::ThreadData, _polling_page);}
1290 static ByteSize saved_exception_pc_offset() { return byte_offset_of(JavaThread, _saved_exception_pc); }
1291 static ByteSize osthread_offset() { return byte_offset_of(JavaThread, _osthread); }
1292 #if INCLUDE_JVMCI
1293 static ByteSize pending_deoptimization_offset() { return byte_offset_of(JavaThread, _pending_deoptimization); }
1294 static ByteSize pending_monitorenter_offset() { return byte_offset_of(JavaThread, _pending_monitorenter); }
1295 static ByteSize pending_failed_speculation_offset() { return byte_offset_of(JavaThread, _pending_failed_speculation); }
1296 static ByteSize jvmci_alternate_call_target_offset() { return byte_offset_of(JavaThread, _jvmci._alternate_call_target); }
1297 static ByteSize jvmci_implicit_exception_pc_offset() { return byte_offset_of(JavaThread, _jvmci._implicit_exception_pc); }
1298 static ByteSize jvmci_counters_offset() { return byte_offset_of(JavaThread, _jvmci_counters); }
1299 #endif // INCLUDE_JVMCI
1300 static ByteSize exception_oop_offset() { return byte_offset_of(JavaThread, _exception_oop); }
1301 static ByteSize exception_pc_offset() { return byte_offset_of(JavaThread, _exception_pc); }
1302 static ByteSize exception_handler_pc_offset() { return byte_offset_of(JavaThread, _exception_handler_pc); }
1303 static ByteSize is_method_handle_return_offset() { return byte_offset_of(JavaThread, _is_method_handle_return); }
1304
1305 static ByteSize active_handles_offset() { return byte_offset_of(JavaThread, _active_handles); }
1306
1307 // StackOverflow offsets
1308 static ByteSize stack_overflow_limit_offset() {
1309 return byte_offset_of(JavaThread, _stack_overflow_state._stack_overflow_limit);
1310 }
1311 static ByteSize stack_guard_state_offset() {
1312 return byte_offset_of(JavaThread, _stack_overflow_state._stack_guard_state);
1313 }
1314 static ByteSize reserved_stack_activation_offset() {
1315 return byte_offset_of(JavaThread, _stack_overflow_state._reserved_stack_activation);
1316 }
1317 static ByteSize shadow_zone_safe_limit() {
1318 return byte_offset_of(JavaThread, _stack_overflow_state._shadow_zone_safe_limit);
1319 }
1320 static ByteSize shadow_zone_growth_watermark() {
1321 return byte_offset_of(JavaThread, _stack_overflow_state._shadow_zone_growth_watermark);
1322 }
1323
1324 static ByteSize suspend_flags_offset() { return byte_offset_of(JavaThread, _suspend_flags); }
1325
1326 static ByteSize do_not_unlock_if_synchronized_offset() { return byte_offset_of(JavaThread, _do_not_unlock_if_synchronized); }
1327 static ByteSize should_post_on_exceptions_flag_offset() {
1328 return byte_offset_of(JavaThread, _should_post_on_exceptions_flag);
1329 }
1330 static ByteSize doing_unsafe_access_offset() { return byte_offset_of(JavaThread, _doing_unsafe_access); }
1331 NOT_PRODUCT(static ByteSize requires_cross_modify_fence_offset() { return byte_offset_of(JavaThread, _requires_cross_modify_fence); })
1332
1333 // Returns the jni environment for this thread
1334 JNIEnv* jni_environment() { return &_jni_environment; }
1335
1336 // Returns the current thread as indicated by the given JNIEnv.
1337 // We don't assert it is Thread::current here as that is done at the
1338 // external JNI entry points where the JNIEnv is passed into the VM.
1339 static JavaThread* thread_from_jni_environment(JNIEnv* env) {
1340 JavaThread* current = (JavaThread*)((intptr_t)env - in_bytes(jni_environment_offset()));
1341 // We can't normally get here in a thread that has completed its
1342 // execution and so "is_terminated", except when the call is from
1343 // AsyncGetCallTrace, which can be triggered by a signal at any point in
1344 // a thread's lifecycle. A thread is also considered terminated if the VM
1345 // has exited, so we have to check this and block in case this is a daemon
1346 // thread returning to the VM (the JNI DirectBuffer entry points rely on
1347 // this).
1348 if (current->is_terminated()) {
1349 current->block_if_vm_exited();
1350 }
1351 return current;
1352 }
1353
1354 // JNI critical regions. These can nest.
1355 bool in_critical() { return _jni_active_critical > 0; }
1356 bool in_last_critical() { return _jni_active_critical == 1; }
1357 inline void enter_critical();
1358 void exit_critical() {
1359 assert(Thread::current() == this, "this must be current thread");
1360 _jni_active_critical--;
1361 assert(_jni_active_critical >= 0, "JNI critical nesting problem?");
1362 }
1363
1364 // Checked JNI: is the programmer required to check for exceptions, if so specify
1365 // which function name. Returning to a Java frame should implicitly clear the
1366 // pending check, this is done for Native->Java transitions (i.e. user JNI code).
1367 // VM->Java transistions are not cleared, it is expected that JNI code enclosed
1368 // within ThreadToNativeFromVM makes proper exception checks (i.e. VM internal).
1369 bool is_pending_jni_exception_check() const { return _pending_jni_exception_check_fn != NULL; }
1370 void clear_pending_jni_exception_check() { _pending_jni_exception_check_fn = NULL; }
1371 const char* get_pending_jni_exception_check() const { return _pending_jni_exception_check_fn; }
1372 void set_pending_jni_exception_check(const char* fn_name) { _pending_jni_exception_check_fn = (char*) fn_name; }
1373
1374 // For deadlock detection
1375 int depth_first_number() { return _depth_first_number; }
1376 void set_depth_first_number(int dfn) { _depth_first_number = dfn; }
1377
1378 private:
1379 void set_monitor_chunks(MonitorChunk* monitor_chunks) { _monitor_chunks = monitor_chunks; }
1380
1381 public:
1382 MonitorChunk* monitor_chunks() const { return _monitor_chunks; }
1383 void add_monitor_chunk(MonitorChunk* chunk);
1384 void remove_monitor_chunk(MonitorChunk* chunk);
1385 bool in_deopt_handler() const { return _in_deopt_handler > 0; }
1386 void inc_in_deopt_handler() { _in_deopt_handler++; }
1387 void dec_in_deopt_handler() {
1388 assert(_in_deopt_handler > 0, "mismatched deopt nesting");
1389 if (_in_deopt_handler > 0) { // robustness
1390 _in_deopt_handler--;
1391 }
1392 }
1393
1394 private:
1395 void set_entry_point(ThreadFunction entry_point) { _entry_point = entry_point; }
1396
1397 // factor out low-level mechanics for use in both normal and error cases
1398 const char* get_thread_name_string(char* buf = NULL, int buflen = 0) const;
1399
1400 public:
1401
1402 // Frame iteration; calls the function f for all frames on the stack
1403 void frames_do(void f(frame*, const RegisterMap*));
1404
1405 // Memory operations
1406 void oops_do_frames(OopClosure* f, CodeBlobClosure* cf);
1407 void oops_do_no_frames(OopClosure* f, CodeBlobClosure* cf);
1408
1409 // Sweeper operations
1410 virtual void nmethods_do(CodeBlobClosure* cf);
1411
1412 // RedefineClasses Support
1413 void metadata_do(MetadataClosure* f);
1414
1415 // Debug method asserting thread states are correct during a handshake operation.
1416 DEBUG_ONLY(void verify_states_for_handshake();)
1417
1418 // Misc. operations
1419 const char* name() const;
1420 const char* type_name() const { return "JavaThread"; }
1421 static const char* name_for(oop thread_obj);
1422
1423 void print_on(outputStream* st, bool print_extended_info) const;
1424 void print_on(outputStream* st) const { print_on(st, false); }
1425 void print() const;
1426 void print_thread_state_on(outputStream*) const PRODUCT_RETURN;
1427 void print_on_error(outputStream* st, char* buf, int buflen) const;
1428 void print_name_on_error(outputStream* st, char* buf, int buflen) const;
1429 void verify();
1430
1431 // Accessing frames
1432 frame last_frame() {
1433 _anchor.make_walkable(this);
1434 return pd_last_frame();
1435 }
1436 javaVFrame* last_java_vframe(RegisterMap* reg_map);
1437
1438 // Returns method at 'depth' java or native frames down the stack
1439 // Used for security checks
1440 Klass* security_get_caller_class(int depth);
1441
1442 // Print stack trace in external format
1443 void print_stack_on(outputStream* st);
1444 void print_stack() { print_stack_on(tty); }
1445
1446 // Print stack traces in various internal formats
1447 void trace_stack() PRODUCT_RETURN;
1448 void trace_stack_from(vframe* start_vf) PRODUCT_RETURN;
1449 void trace_frames() PRODUCT_RETURN;
1450
1451 // Print an annotated view of the stack frames
1452 void print_frame_layout(int depth = 0, bool validate_only = false) NOT_DEBUG_RETURN;
1453 void validate_frame_layout() {
1454 print_frame_layout(0, true);
1455 }
1456
1457 // Function for testing deoptimization
1458 void deoptimize();
1459 void make_zombies();
1460
1461 void deoptimize_marked_methods();
1462
1463 public:
1464 // Returns the running thread as a JavaThread
1465 static JavaThread* current() {
1466 return JavaThread::cast(Thread::current());
1467 }
1468
1469 // Returns the current thread as a JavaThread, or NULL if not attached
1470 static inline JavaThread* current_or_null();
1471
1472 // Casts
1473 static JavaThread* cast(Thread* t) {
1474 assert(t->is_Java_thread(), "incorrect cast to JavaThread");
1475 return static_cast<JavaThread*>(t);
1476 }
1477
1478 static const JavaThread* cast(const Thread* t) {
1479 assert(t->is_Java_thread(), "incorrect cast to const JavaThread");
1480 return static_cast<const JavaThread*>(t);
1481 }
1482
1483 // Returns the active Java thread. Do not use this if you know you are calling
1484 // from a JavaThread, as it's slower than JavaThread::current. If called from
1485 // the VMThread, it also returns the JavaThread that instigated the VMThread's
1486 // operation. You may not want that either.
1487 static JavaThread* active();
1488
1489 protected:
1490 virtual void pre_run();
1491 virtual void run();
1492 void thread_main_inner();
1493 virtual void post_run();
1494
1495 public:
1496 // Thread local information maintained by JVMTI.
1497 void set_jvmti_thread_state(JvmtiThreadState *value) { _jvmti_thread_state = value; }
1498 // A JvmtiThreadState is lazily allocated. This jvmti_thread_state()
1499 // getter is used to get this JavaThread's JvmtiThreadState if it has
1500 // one which means NULL can be returned. JvmtiThreadState::state_for()
1501 // is used to get the specified JavaThread's JvmtiThreadState if it has
1502 // one or it allocates a new JvmtiThreadState for the JavaThread and
1503 // returns it. JvmtiThreadState::state_for() will return NULL only if
1504 // the specified JavaThread is exiting.
1505 JvmtiThreadState *jvmti_thread_state() const { return _jvmti_thread_state; }
1506 static ByteSize jvmti_thread_state_offset() { return byte_offset_of(JavaThread, _jvmti_thread_state); }
1507
1508 // JVMTI PopFrame support
1509 // Setting and clearing popframe_condition
1510 // All of these enumerated values are bits. popframe_pending
1511 // indicates that a PopFrame() has been requested and not yet been
1512 // completed. popframe_processing indicates that that PopFrame() is in
1513 // the process of being completed. popframe_force_deopt_reexecution_bit
1514 // indicates that special handling is required when returning to a
1515 // deoptimized caller.
1516 enum PopCondition {
1517 popframe_inactive = 0x00,
1518 popframe_pending_bit = 0x01,
1519 popframe_processing_bit = 0x02,
1520 popframe_force_deopt_reexecution_bit = 0x04
1521 };
1522 PopCondition popframe_condition() { return (PopCondition) _popframe_condition; }
1523 void set_popframe_condition(PopCondition c) { _popframe_condition = c; }
1524 void set_popframe_condition_bit(PopCondition c) { _popframe_condition |= c; }
1525 void clear_popframe_condition() { _popframe_condition = popframe_inactive; }
1526 static ByteSize popframe_condition_offset() { return byte_offset_of(JavaThread, _popframe_condition); }
1527 bool has_pending_popframe() { return (popframe_condition() & popframe_pending_bit) != 0; }
1528 bool popframe_forcing_deopt_reexecution() { return (popframe_condition() & popframe_force_deopt_reexecution_bit) != 0; }
1529 void clear_popframe_forcing_deopt_reexecution() { _popframe_condition &= ~popframe_force_deopt_reexecution_bit; }
1530
1531 bool pop_frame_in_process(void) { return ((_popframe_condition & popframe_processing_bit) != 0); }
1532 void set_pop_frame_in_process(void) { _popframe_condition |= popframe_processing_bit; }
1533 void clr_pop_frame_in_process(void) { _popframe_condition &= ~popframe_processing_bit; }
1534
1535 int frames_to_pop_failed_realloc() const { return _frames_to_pop_failed_realloc; }
1536 void set_frames_to_pop_failed_realloc(int nb) { _frames_to_pop_failed_realloc = nb; }
1537 void dec_frames_to_pop_failed_realloc() { _frames_to_pop_failed_realloc--; }
1538
1539 private:
1540 // Saved incoming arguments to popped frame.
1541 // Used only when popped interpreted frame returns to deoptimized frame.
1542 void* _popframe_preserved_args;
1543 int _popframe_preserved_args_size;
1544
1545 public:
1546 void popframe_preserve_args(ByteSize size_in_bytes, void* start);
1547 void* popframe_preserved_args();
1548 ByteSize popframe_preserved_args_size();
1549 WordSize popframe_preserved_args_size_in_words();
1550 void popframe_free_preserved_args();
1551
1552
1553 private:
1554 JvmtiThreadState *_jvmti_thread_state;
1555
1556 // Used by the interpreter in fullspeed mode for frame pop, method
1557 // entry, method exit and single stepping support. This field is
1558 // only set to non-zero at a safepoint or using a direct handshake
1559 // (see EnterInterpOnlyModeClosure).
1560 // It can be set to zero asynchronously to this threads execution (i.e., without
1561 // safepoint/handshake or a lock) so we have to be very careful.
1562 // Accesses by other threads are synchronized using JvmtiThreadState_lock though.
1563 int _interp_only_mode;
1564
1565 public:
1566 // used by the interpreter for fullspeed debugging support (see above)
1567 static ByteSize interp_only_mode_offset() { return byte_offset_of(JavaThread, _interp_only_mode); }
1568 bool is_interp_only_mode() { return (_interp_only_mode != 0); }
1569 int get_interp_only_mode() { return _interp_only_mode; }
1570 void increment_interp_only_mode() { ++_interp_only_mode; }
1571 void decrement_interp_only_mode() { --_interp_only_mode; }
1572
1573 // support for cached flag that indicates whether exceptions need to be posted for this thread
1574 // if this is false, we can avoid deoptimizing when events are thrown
1575 // this gets set to reflect whether jvmtiExport::post_exception_throw would actually do anything
1576 private:
1577 int _should_post_on_exceptions_flag;
1578
1579 public:
1580 int should_post_on_exceptions_flag() { return _should_post_on_exceptions_flag; }
1581 void set_should_post_on_exceptions_flag(int val) { _should_post_on_exceptions_flag = val; }
1582
1583 private:
1584 ThreadStatistics *_thread_stat;
1585
1586 public:
1587 ThreadStatistics* get_thread_stat() const { return _thread_stat; }
1588
1589 // Return a blocker object for which this thread is blocked parking.
1590 oop current_park_blocker();
1591
1592 private:
1593 static size_t _stack_size_at_create;
1594
1595 public:
1596 static inline size_t stack_size_at_create(void) {
1597 return _stack_size_at_create;
1598 }
1599 static inline void set_stack_size_at_create(size_t value) {
1600 _stack_size_at_create = value;
1601 }
1602
1603 // Machine dependent stuff
1604 #include OS_CPU_HEADER(thread)
1605
1606 // JSR166 per-thread parker
1607 private:
1608 Parker _parker;
1609 public:
1610 Parker* parker() { return &_parker; }
1611
1612 public:
1613 // clearing/querying jni attach status
1614 bool is_attaching_via_jni() const { return _jni_attach_state == _attaching_via_jni; }
1615 bool has_attached_via_jni() const { return is_attaching_via_jni() || _jni_attach_state == _attached_via_jni; }
1616 inline void set_done_attaching_via_jni();
1617
1618 // Stack dump assistance:
1619 // Track the class we want to initialize but for which we have to wait
1620 // on its init_lock() because it is already being initialized.
1621 void set_class_to_be_initialized(InstanceKlass* k);
1622 InstanceKlass* class_to_be_initialized() const;
1623
1624 private:
1625 InstanceKlass* _class_to_be_initialized;
1626
1627 // java.lang.Thread.sleep support
1628 ParkEvent * _SleepEvent;
1629 public:
1630 bool sleep(jlong millis);
1631
1632 // java.lang.Thread interruption support
1633 void interrupt();
1634 bool is_interrupted(bool clear_interrupted);
1635
1636 static OopStorage* thread_oop_storage();
1637
1638 static void verify_cross_modify_fence_failure(JavaThread *thread) PRODUCT_RETURN;
1639
1640 // Helper function to create the java.lang.Thread object for a
1641 // VM-internal thread. The thread will have the given name, be
1642 // part of the System ThreadGroup and if is_visible is true will be
1643 // discoverable via the system ThreadGroup.
1644 static Handle create_system_thread_object(const char* name, bool is_visible, TRAPS);
1645
1646 // Helper function to start a VM-internal daemon thread.
1647 // E.g. ServiceThread, NotificationThread, CompilerThread etc.
1648 static void start_internal_daemon(JavaThread* current, JavaThread* target,
1649 Handle thread_oop, ThreadPriority prio);
1650
1651 // Helper function to do vm_exit_on_initialization for osthread
1652 // resource allocation failure.
1653 static void vm_exit_on_osthread_failure(JavaThread* thread);
1654 };
1655
1656 inline JavaThread* JavaThread::current_or_null() {
1657 Thread* current = Thread::current_or_null();
1658 return current != nullptr ? JavaThread::cast(current) : nullptr;
1659 }
1660
1661 // The active thread queue. It also keeps track of the current used
1662 // thread priorities.
1663 class Threads: AllStatic {
1664 friend class VMStructs;
1665 private:
1666 static int _number_of_threads;
1667 static int _number_of_non_daemon_threads;
1668 static int _return_code;
1669 static uintx _thread_claim_token;
1670 #ifdef ASSERT
1671 static bool _vm_complete;
1672 #endif
1673
1674 static void initialize_java_lang_classes(JavaThread* main_thread, TRAPS);
1675 static void initialize_jsr292_core_classes(TRAPS);
1676
1677 public:
1678 // Thread management
1679 // force_daemon is a concession to JNI, where we may need to add a
1680 // thread to the thread list before allocating its thread object
1681 static void add(JavaThread* p, bool force_daemon = false);
1682 static void remove(JavaThread* p, bool is_daemon);
1683 static void non_java_threads_do(ThreadClosure* tc);
1684 static void java_threads_do(ThreadClosure* tc);
1685 static void java_threads_and_vm_thread_do(ThreadClosure* tc);
1686 static void threads_do(ThreadClosure* tc);
1687 static void possibly_parallel_threads_do(bool is_par, ThreadClosure* tc);
1688
1689 // Initializes the vm and creates the vm thread
1690 static jint create_vm(JavaVMInitArgs* args, bool* canTryAgain);
1691 static void convert_vm_init_libraries_to_agents();
1692 static void create_vm_init_libraries();
1693 static void create_vm_init_agents();
1694 static void shutdown_vm_agents();
1695 static void destroy_vm();
1696 // Supported VM versions via JNI
1697 // Includes JNI_VERSION_1_1
1698 static jboolean is_supported_jni_version_including_1_1(jint version);
1699 // Does not include JNI_VERSION_1_1
1700 static jboolean is_supported_jni_version(jint version);
1701
1702 // The "thread claim token" provides a way for threads to be claimed
1703 // by parallel worker tasks.
1704 //
1705 // Each thread contains a "token" field. A task will claim the
1706 // thread only if its token is different from the global token,
1707 // which is updated by calling change_thread_claim_token(). When
1708 // a thread is claimed, it's token is set to the global token value
1709 // so other threads in the same iteration pass won't claim it.
1710 //
1711 // For this to work change_thread_claim_token() needs to be called
1712 // exactly once in sequential code before starting parallel tasks
1713 // that should claim threads.
1714 //
1715 // New threads get their token set to 0 and change_thread_claim_token()
1716 // never sets the global token to 0.
1717 static uintx thread_claim_token() { return _thread_claim_token; }
1718 static void change_thread_claim_token();
1719 static void assert_all_threads_claimed() NOT_DEBUG_RETURN;
1720
1721 // Apply "f->do_oop" to all root oops in all threads.
1722 // This version may only be called by sequential code.
1723 static void oops_do(OopClosure* f, CodeBlobClosure* cf);
1724 // This version may be called by sequential or parallel code.
1725 static void possibly_parallel_oops_do(bool is_par, OopClosure* f, CodeBlobClosure* cf);
1726
1727 // RedefineClasses support
1728 static void metadata_do(MetadataClosure* f);
1729 static void metadata_handles_do(void f(Metadata*));
1730
1731 #ifdef ASSERT
1732 static bool is_vm_complete() { return _vm_complete; }
1733 #endif // ASSERT
1734
1735 // Verification
1736 static void verify();
1737 static void print_on(outputStream* st, bool print_stacks, bool internal_format, bool print_concurrent_locks, bool print_extended_info);
1738 static void print(bool print_stacks, bool internal_format) {
1739 // this function is only used by debug.cpp
1740 print_on(tty, print_stacks, internal_format, false /* no concurrent lock printed */, false /* simple format */);
1741 }
1742 static void print_on_error(outputStream* st, Thread* current, char* buf, int buflen);
1743 static void print_on_error(Thread* this_thread, outputStream* st, Thread* current, char* buf,
1744 int buflen, bool* found_current);
1745 static void print_threads_compiling(outputStream* st, char* buf, int buflen, bool short_form = false);
1746
1747 // Get Java threads that are waiting to enter a monitor.
1748 static GrowableArray<JavaThread*>* get_pending_threads(ThreadsList * t_list,
1749 int count, address monitor);
1750
1751 // Get owning Java thread from the monitor's owner field.
1752 static JavaThread *owning_thread_from_monitor_owner(ThreadsList * t_list,
1753 address owner);
1754
1755 // Number of threads on the active threads list
1756 static int number_of_threads() { return _number_of_threads; }
1757 // Number of non-daemon threads on the active threads list
1758 static int number_of_non_daemon_threads() { return _number_of_non_daemon_threads; }
1759
1760 // Deoptimizes all frames tied to marked nmethods
1761 static void deoptimized_wrt_marked_nmethods();
1762
1763 struct Test; // For private gtest access.
1764 };
1765
1766 class UnlockFlagSaver {
1767 private:
1768 JavaThread* _thread;
1769 bool _do_not_unlock;
1770 public:
1771 UnlockFlagSaver(JavaThread* t) {
1772 _thread = t;
1773 _do_not_unlock = t->do_not_unlock_if_synchronized();
1774 t->set_do_not_unlock_if_synchronized(false);
1775 }
1776 ~UnlockFlagSaver() {
1777 _thread->set_do_not_unlock_if_synchronized(_do_not_unlock);
1778 }
1779 };
1780
1781 class JNIHandleMark : public StackObj {
1782 JavaThread* _thread;
1783 public:
1784 JNIHandleMark(JavaThread* thread) : _thread(thread) {
1785 thread->push_jni_handle_block();
1786 }
1787 ~JNIHandleMark() { _thread->pop_jni_handle_block(); }
1788 };
1789
1790 #endif // SHARE_RUNTIME_THREAD_HPP