1 /*
2 * Copyright (c) 1997, 2019, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #ifndef SHARE_RUNTIME_THREAD_HPP
26 #define SHARE_RUNTIME_THREAD_HPP
27
28 #include "jni.h"
29 #include "code/compiledMethod.hpp"
30 #include "gc/shared/gcThreadLocalData.hpp"
31 #include "gc/shared/threadLocalAllocBuffer.hpp"
32 #include "memory/allocation.hpp"
33 #include "oops/oop.hpp"
34 #include "prims/jvmtiExport.hpp"
35 #include "runtime/frame.hpp"
36 #include "runtime/globals.hpp"
37 #include "runtime/handshake.hpp"
38 #include "runtime/javaFrameAnchor.hpp"
39 #include "runtime/jniHandles.hpp"
40 #include "runtime/mutexLocker.hpp"
41 #include "runtime/os.hpp"
42 #include "runtime/osThread.hpp"
43 #include "runtime/park.hpp"
44 #include "runtime/stubRoutines.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/macros.hpp"
52 #ifdef ZERO
53 # include "stack_zero.hpp"
54 #endif
55 #if INCLUDE_JFR
56 #include "jfr/support/jfrThreadExtension.hpp"
57 #endif
58
59
60 class SafeThreadsListPtr;
61 class ThreadSafepointState;
62 class ThreadsList;
63 class ThreadsSMRSupport;
64
65 class JvmtiThreadState;
66 class ThreadStatistics;
67 class ConcurrentLocksDump;
68 class ParkEvent;
69 class Parker;
70 class MonitorInfo;
71
72 class ciEnv;
73 class CompileThread;
74 class CompileLog;
75 class CompileTask;
76 class CompileQueue;
77 class CompilerCounters;
78
79 class vframeArray;
80 class vframe;
81 class javaVFrame;
82
83 class DeoptResourceMark;
84 class jvmtiDeferredLocalVariableSet;
85
86 class ThreadClosure;
87 class ICRefillVerifier;
88 class IdealGraphPrinter;
89
90 class JVMCIEnv;
91 class JVMCIPrimitiveArray;
92
93 class Metadata;
94 class ResourceArea;
95
96 DEBUG_ONLY(class ResourceMark;)
97
98 class WorkerThread;
99
100 // Class hierarchy
101 // - Thread
102 // - JavaThread
103 // - various subclasses eg CompilerThread, ServiceThread
104 // - NonJavaThread
105 // - NamedThread
106 // - VMThread
107 // - ConcurrentGCThread
108 // - WorkerThread
109 // - GangWorker
110 // - WatcherThread
111 // - JfrThreadSampler
112 //
113 // All Thread subclasses must be either JavaThread or NonJavaThread.
114 // This means !t->is_Java_thread() iff t is a NonJavaThread, or t is
115 // a partially constructed/destroyed Thread.
116
117 // Thread execution sequence and actions:
118 // All threads:
119 // - thread_native_entry // per-OS native entry point
120 // - stack initialization
121 // - other OS-level initialization (signal masks etc)
122 // - handshake with creating thread (if not started suspended)
123 // - this->call_run() // common shared entry point
124 // - shared common initialization
125 // - this->pre_run() // virtual per-thread-type initialization
126 // - this->run() // virtual per-thread-type "main" logic
127 // - shared common tear-down
128 // - this->post_run() // virtual per-thread-type tear-down
129 // - // 'this' no longer referenceable
130 // - OS-level tear-down (minimal)
131 // - final logging
132 //
133 // For JavaThread:
134 // - this->run() // virtual but not normally overridden
135 // - this->thread_main_inner() // extra call level to ensure correct stack calculations
136 // - this->entry_point() // set differently for each kind of JavaThread
137
138 class Thread: public ThreadShadow {
139 friend class VMStructs;
140 friend class JVMCIVMStructs;
141 private:
142
143 #ifndef USE_LIBRARY_BASED_TLS_ONLY
144 // Current thread is maintained as a thread-local variable
145 static THREAD_LOCAL_DECL Thread* _thr_current;
146 #endif
147
148 // Thread local data area available to the GC. The internal
149 // structure and contents of this data area is GC-specific.
150 // Only GC and GC barrier code should access this data area.
151 GCThreadLocalData _gc_data;
152
153 public:
154 static ByteSize gc_data_offset() {
155 return byte_offset_of(Thread, _gc_data);
156 }
157
158 template <typename T> T* gc_data() {
159 STATIC_ASSERT(sizeof(T) <= sizeof(_gc_data));
160 return reinterpret_cast<T*>(&_gc_data);
161 }
162
163 // Exception handling
164 // (Note: _pending_exception and friends are in ThreadShadow)
165 //oop _pending_exception; // pending exception for current thread
166 // const char* _exception_file; // file information for exception (debugging only)
167 // int _exception_line; // line information for exception (debugging only)
168 protected:
169
170 DEBUG_ONLY(static Thread* _starting_thread;)
171
172 // Support for forcing alignment of thread objects for biased locking
173 void* _real_malloc_address;
174
175 // JavaThread lifecycle support:
176 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
177 friend class ScanHazardPtrGatherProtectedThreadsClosure; // for cmpxchg_threads_hazard_ptr(), get_threads_hazard_ptr(), is_hazard_ptr_tagged() access
178 friend class ScanHazardPtrGatherThreadsListClosure; // for get_threads_hazard_ptr(), untag_hazard_ptr() access
179 friend class ScanHazardPtrPrintMatchingThreadsClosure; // for get_threads_hazard_ptr(), is_hazard_ptr_tagged() access
180 friend class ThreadsSMRSupport; // for _nested_threads_hazard_ptr_cnt, _threads_hazard_ptr, _threads_list_ptr access
181
182 ThreadsList* volatile _threads_hazard_ptr;
183 SafeThreadsListPtr* _threads_list_ptr;
184 ThreadsList* cmpxchg_threads_hazard_ptr(ThreadsList* exchange_value, ThreadsList* compare_value);
185 ThreadsList* get_threads_hazard_ptr();
186 void set_threads_hazard_ptr(ThreadsList* new_list);
187 static bool is_hazard_ptr_tagged(ThreadsList* list) {
188 return (intptr_t(list) & intptr_t(1)) == intptr_t(1);
189 }
190 static ThreadsList* tag_hazard_ptr(ThreadsList* list) {
191 return (ThreadsList*)(intptr_t(list) | intptr_t(1));
192 }
193 static ThreadsList* untag_hazard_ptr(ThreadsList* list) {
194 return (ThreadsList*)(intptr_t(list) & ~intptr_t(1));
195 }
196 // This field is enabled via -XX:+EnableThreadSMRStatistics:
197 uint _nested_threads_hazard_ptr_cnt;
198 void dec_nested_threads_hazard_ptr_cnt() {
199 assert(_nested_threads_hazard_ptr_cnt != 0, "mismatched {dec,inc}_nested_threads_hazard_ptr_cnt()");
200 _nested_threads_hazard_ptr_cnt--;
201 }
202 void inc_nested_threads_hazard_ptr_cnt() {
203 _nested_threads_hazard_ptr_cnt++;
204 }
205 uint nested_threads_hazard_ptr_cnt() {
206 return _nested_threads_hazard_ptr_cnt;
207 }
208
209 public:
210 void* operator new(size_t size) throw() { return allocate(size, true); }
211 void* operator new(size_t size, const std::nothrow_t& nothrow_constant) throw() {
212 return allocate(size, false); }
213 void operator delete(void* p);
214
215 protected:
216 static void* allocate(size_t size, bool throw_excpt, MEMFLAGS flags = mtThread);
217 private:
218
219 // ***************************************************************
220 // Suspend and resume support
221 // ***************************************************************
222 //
223 // VM suspend/resume no longer exists - it was once used for various
224 // things including safepoints but was deprecated and finally removed
225 // in Java 7. Because VM suspension was considered "internal" Java-level
226 // suspension was considered "external", and this legacy naming scheme
227 // remains.
228 //
229 // External suspend/resume requests come from JVM_SuspendThread,
230 // JVM_ResumeThread, JVMTI SuspendThread, and finally JVMTI
231 // ResumeThread. External
232 // suspend requests cause _external_suspend to be set and external
233 // resume requests cause _external_suspend to be cleared.
234 // External suspend requests do not nest on top of other external
235 // suspend requests. The higher level APIs reject suspend requests
236 // for already suspended threads.
237 //
238 // The external_suspend
239 // flag is checked by has_special_runtime_exit_condition() and java thread
240 // will self-suspend when handle_special_runtime_exit_condition() is
241 // called. Most uses of the _thread_blocked state in JavaThreads are
242 // considered the same as being externally suspended; if the blocking
243 // condition lifts, the JavaThread will self-suspend. Other places
244 // where VM checks for external_suspend include:
245 // + mutex granting (do not enter monitors when thread is suspended)
246 // + state transitions from _thread_in_native
247 //
248 // In general, java_suspend() does not wait for an external suspend
249 // request to complete. When it returns, the only guarantee is that
250 // the _external_suspend field is true.
251 //
252 // wait_for_ext_suspend_completion() is used to wait for an external
253 // suspend request to complete. External suspend requests are usually
254 // followed by some other interface call that requires the thread to
255 // be quiescent, e.g., GetCallTrace(). By moving the "wait time" into
256 // the interface that requires quiescence, we give the JavaThread a
257 // chance to self-suspend before we need it to be quiescent. This
258 // improves overall suspend/query performance.
259 //
260 // _suspend_flags controls the behavior of java_ suspend/resume.
261 // It must be set under the protection of SR_lock. Read from the flag is
262 // OK without SR_lock as long as the value is only used as a hint.
263 // (e.g., check _external_suspend first without lock and then recheck
264 // inside SR_lock and finish the suspension)
265 //
266 // _suspend_flags is also overloaded for other "special conditions" so
267 // that a single check indicates whether any special action is needed
268 // eg. for async exceptions.
269 // -------------------------------------------------------------------
270 // Notes:
271 // 1. The suspend/resume logic no longer uses ThreadState in OSThread
272 // but we still update its value to keep other part of the system (mainly
273 // JVMTI) happy. ThreadState is legacy code (see notes in
274 // osThread.hpp).
275 //
276 // 2. It would be more natural if set_external_suspend() is private and
277 // part of java_suspend(), but that probably would affect the suspend/query
278 // performance. Need more investigation on this.
279
280 // suspend/resume lock: used for self-suspend
281 Monitor* _SR_lock;
282
283 protected:
284 enum SuspendFlags {
285 // NOTE: avoid using the sign-bit as cc generates different test code
286 // when the sign-bit is used, and sometimes incorrectly - see CR 6398077
287
288 _external_suspend = 0x20000000U, // thread is asked to self suspend
289 _ext_suspended = 0x40000000U, // thread has self-suspended
290
291 _has_async_exception = 0x00000001U, // there is a pending async exception
292 _critical_native_unlock = 0x00000002U, // Must call back to unlock JNI critical lock
293
294 _trace_flag = 0x00000004U // call tracing backend
295 };
296
297 // various suspension related flags - atomically updated
298 // overloaded for async exception checking in check_special_condition_for_native_trans.
299 volatile uint32_t _suspend_flags;
300
301 private:
302 int _num_nested_signal;
303
304 DEBUG_ONLY(bool _suspendible_thread;)
305
306 public:
307 void enter_signal_handler() { _num_nested_signal++; }
308 void leave_signal_handler() { _num_nested_signal--; }
309 bool is_inside_signal_handler() const { return _num_nested_signal > 0; }
310
311 // Determines if a heap allocation failure will be retried
312 // (e.g., by deoptimizing and re-executing in the interpreter).
313 // In this case, the failed allocation must raise
314 // Universe::out_of_memory_error_retry() and omit side effects
315 // such as JVMTI events and handling -XX:+HeapDumpOnOutOfMemoryError
316 // and -XX:OnOutOfMemoryError.
317 virtual bool in_retryable_allocation() const { return false; }
318
319 #ifdef ASSERT
320 void set_suspendible_thread() {
321 _suspendible_thread = true;
322 }
323
324 void clear_suspendible_thread() {
325 _suspendible_thread = false;
326 }
327
328 bool is_suspendible_thread() { return _suspendible_thread; }
329 #endif
330
331 private:
332 // Active_handles points to a block of handles
333 JNIHandleBlock* _active_handles;
334
335 // One-element thread local free list
336 JNIHandleBlock* _free_handle_block;
337
338 // Point to the last handle mark
339 HandleMark* _last_handle_mark;
340
341 // Claim value for parallel iteration over threads.
342 uintx _threads_do_token;
343
344 // Support for GlobalCounter
345 private:
346 volatile uintx _rcu_counter;
347 public:
348 volatile uintx* get_rcu_counter() {
349 return &_rcu_counter;
350 }
351
352 public:
353 void set_last_handle_mark(HandleMark* mark) { _last_handle_mark = mark; }
354 HandleMark* last_handle_mark() const { return _last_handle_mark; }
355 private:
356
357 #ifdef ASSERT
358 ICRefillVerifier* _missed_ic_stub_refill_verifier;
359
360 public:
361 ICRefillVerifier* missed_ic_stub_refill_verifier() {
362 return _missed_ic_stub_refill_verifier;
363 }
364
365 void set_missed_ic_stub_refill_verifier(ICRefillVerifier* verifier) {
366 _missed_ic_stub_refill_verifier = verifier;
367 }
368 #endif
369
370 private:
371
372 // debug support for checking if code does allow safepoints or not
373 // GC points in the VM can happen because of allocation, invoking a VM operation, or blocking on
374 // mutex, or blocking on an object synchronizer (Java locking).
375 // If !allow_safepoint(), then an assertion failure will happen in any of the above cases
376 // If !allow_allocation(), then an assertion failure will happen during allocation
377 // (Hence, !allow_safepoint() => !allow_allocation()).
378 //
379 // The two classes NoSafepointVerifier and No_Allocation_Verifier are used to set these counters.
380 //
381 NOT_PRODUCT(int _allow_safepoint_count;) // If 0, thread allow a safepoint to happen
382 debug_only(int _allow_allocation_count;) // If 0, the thread is allowed to allocate oops.
383
384 // Used by SkipGCALot class.
385 NOT_PRODUCT(bool _skip_gcalot;) // Should we elide gc-a-lot?
386
387 friend class NoAllocVerifier;
388 friend class NoSafepointVerifier;
389 friend class PauseNoSafepointVerifier;
390 friend class GCLocker;
391
392 volatile void* _polling_page; // Thread local polling page
393
394 ThreadLocalAllocBuffer _tlab; // Thread-local eden
395 jlong _allocated_bytes; // Cumulative number of bytes allocated on
396 // the Java heap
397 ThreadHeapSampler _heap_sampler; // For use when sampling the memory.
398
399 ThreadStatisticalInfo _statistical_info; // Statistics about the thread
400
401 JFR_ONLY(DEFINE_THREAD_LOCAL_FIELD_JFR;) // Thread-local data for jfr
402
403 int _vm_operation_started_count; // VM_Operation support
404 int _vm_operation_completed_count; // VM_Operation support
405
406 ObjectMonitor* _current_pending_monitor; // ObjectMonitor this thread
407 // is waiting to lock
408 bool _current_pending_monitor_is_from_java; // locking is from Java code
409
410 // ObjectMonitor on which this thread called Object.wait()
411 ObjectMonitor* _current_waiting_monitor;
412
413 // Private thread-local objectmonitor list - a simple cache organized as a SLL.
414 public:
415 ObjectMonitor* omFreeList;
416 int omFreeCount; // length of omFreeList
417 int omFreeProvision; // reload chunk size
418 ObjectMonitor* omInUseList; // SLL to track monitors in circulation
419 int omInUseCount; // length of omInUseList
420
421 #ifdef ASSERT
422 private:
423 volatile uint64_t _visited_for_critical_count;
424
425 public:
426 void set_visited_for_critical_count(uint64_t safepoint_id) {
427 assert(_visited_for_critical_count == 0, "Must be reset before set");
428 assert((safepoint_id & 0x1) == 1, "Must be odd");
429 _visited_for_critical_count = safepoint_id;
430 }
431 void reset_visited_for_critical_count(uint64_t safepoint_id) {
432 assert(_visited_for_critical_count == safepoint_id, "Was not visited");
433 _visited_for_critical_count = 0;
434 }
435 bool was_visited_for_critical_count(uint64_t safepoint_id) const {
436 return _visited_for_critical_count == safepoint_id;
437 }
438 #endif
439
440 public:
441 enum {
442 is_definitely_current_thread = true
443 };
444
445 // Constructor
446 Thread();
447 virtual ~Thread() = 0; // Thread is abstract.
448
449 // Manage Thread::current()
450 void initialize_thread_current();
451 static void clear_thread_current(); // TLS cleanup needed before threads terminate
452
453 protected:
454 // To be implemented by children.
455 virtual void run() = 0;
456 virtual void pre_run() = 0;
457 virtual void post_run() = 0; // Note: Thread must not be deleted prior to calling this!
458
459 #ifdef ASSERT
460 enum RunState {
461 PRE_CALL_RUN,
462 CALL_RUN,
463 PRE_RUN,
464 RUN,
465 POST_RUN
466 // POST_CALL_RUN - can't define this one as 'this' may be deleted when we want to set it
467 };
468 RunState _run_state; // for lifecycle checks
469 #endif
470
471
472 public:
473 // invokes <ChildThreadClass>::run(), with common preparations and cleanups.
474 void call_run();
475
476 // Testers
477 virtual bool is_VM_thread() const { return false; }
478 virtual bool is_Java_thread() const { return false; }
479 virtual bool is_Compiler_thread() const { return false; }
480 virtual bool is_Code_cache_sweeper_thread() const { return false; }
481 virtual bool is_hidden_from_external_view() const { return false; }
482 virtual bool is_jvmti_agent_thread() const { return false; }
483 // True iff the thread can perform GC operations at a safepoint.
484 // Generally will be true only of VM thread and parallel GC WorkGang
485 // threads.
486 virtual bool is_GC_task_thread() const { return false; }
487 virtual bool is_Watcher_thread() const { return false; }
488 virtual bool is_ConcurrentGC_thread() const { return false; }
489 virtual bool is_Named_thread() const { return false; }
490 virtual bool is_Worker_thread() const { return false; }
491
492 // Can this thread make Java upcalls
493 virtual bool can_call_java() const { return false; }
494
495 // Casts
496 virtual WorkerThread* as_Worker_thread() const { return NULL; }
497
498 virtual char* name() const { return (char*)"Unknown thread"; }
499
500 // Returns the current thread (ASSERTS if NULL)
501 static inline Thread* current();
502 // Returns the current thread, or NULL if not attached
503 static inline Thread* current_or_null();
504 // Returns the current thread, or NULL if not attached, and is
505 // safe for use from signal-handlers
506 static inline Thread* current_or_null_safe();
507
508 // Common thread operations
509 #ifdef ASSERT
510 static void check_for_dangling_thread_pointer(Thread *thread);
511 #endif
512 static void set_priority(Thread* thread, ThreadPriority priority);
513 static ThreadPriority get_priority(const Thread* const thread);
514 static void start(Thread* thread);
515 static void interrupt(Thread* thr);
516 static bool is_interrupted(Thread* thr, bool clear_interrupted);
517
518 void set_native_thread_name(const char *name) {
519 assert(Thread::current() == this, "set_native_thread_name can only be called on the current thread");
520 os::set_native_thread_name(name);
521 }
522
523 ObjectMonitor** omInUseList_addr() { return (ObjectMonitor **)&omInUseList; }
524 Monitor* SR_lock() const { return _SR_lock; }
525
526 bool has_async_exception() const { return (_suspend_flags & _has_async_exception) != 0; }
527
528 inline void set_suspend_flag(SuspendFlags f);
529 inline void clear_suspend_flag(SuspendFlags f);
530
531 inline void set_has_async_exception();
532 inline void clear_has_async_exception();
533
534 bool do_critical_native_unlock() const { return (_suspend_flags & _critical_native_unlock) != 0; }
535
536 inline void set_critical_native_unlock();
537 inline void clear_critical_native_unlock();
538
539 inline void set_trace_flag();
540 inline void clear_trace_flag();
541
542 // Support for Unhandled Oop detection
543 // Add the field for both, fastdebug and debug, builds to keep
544 // Thread's fields layout the same.
545 // Note: CHECK_UNHANDLED_OOPS is defined only for fastdebug build.
546 #ifdef CHECK_UNHANDLED_OOPS
547 private:
548 UnhandledOops* _unhandled_oops;
549 #elif defined(ASSERT)
550 private:
551 void* _unhandled_oops;
552 #endif
553 #ifdef CHECK_UNHANDLED_OOPS
554 public:
555 UnhandledOops* unhandled_oops() { return _unhandled_oops; }
556 // Mark oop safe for gc. It may be stack allocated but won't move.
557 void allow_unhandled_oop(oop *op) {
558 if (CheckUnhandledOops) unhandled_oops()->allow_unhandled_oop(op);
559 }
560 // Clear oops at safepoint so crashes point to unhandled oop violator
561 void clear_unhandled_oops() {
562 if (CheckUnhandledOops) unhandled_oops()->clear_unhandled_oops();
563 }
564 #endif // CHECK_UNHANDLED_OOPS
565
566 public:
567 #ifndef PRODUCT
568 bool skip_gcalot() { return _skip_gcalot; }
569 void set_skip_gcalot(bool v) { _skip_gcalot = v; }
570 #endif
571
572 // Installs a pending exception to be inserted later
573 static void send_async_exception(oop thread_oop, oop java_throwable);
574
575 // Resource area
576 ResourceArea* resource_area() const { return _resource_area; }
577 void set_resource_area(ResourceArea* area) { _resource_area = area; }
578
579 OSThread* osthread() const { return _osthread; }
580 void set_osthread(OSThread* thread) { _osthread = thread; }
581
582 // JNI handle support
583 JNIHandleBlock* active_handles() const { return _active_handles; }
584 void set_active_handles(JNIHandleBlock* block) { _active_handles = block; }
585 JNIHandleBlock* free_handle_block() const { return _free_handle_block; }
586 void set_free_handle_block(JNIHandleBlock* block) { _free_handle_block = block; }
587
588 // Internal handle support
589 HandleArea* handle_area() const { return _handle_area; }
590 void set_handle_area(HandleArea* area) { _handle_area = area; }
591
592 GrowableArray<Metadata*>* metadata_handles() const { return _metadata_handles; }
593 void set_metadata_handles(GrowableArray<Metadata*>* handles){ _metadata_handles = handles; }
594
595 // Thread-Local Allocation Buffer (TLAB) support
596 ThreadLocalAllocBuffer& tlab() { return _tlab; }
597 void initialize_tlab() {
598 if (UseTLAB) {
599 tlab().initialize();
600 }
601 }
602
603 jlong allocated_bytes() { return _allocated_bytes; }
604 void set_allocated_bytes(jlong value) { _allocated_bytes = value; }
605 void incr_allocated_bytes(jlong size) { _allocated_bytes += size; }
606 inline jlong cooked_allocated_bytes();
607
608 ThreadHeapSampler& heap_sampler() { return _heap_sampler; }
609
610 ThreadStatisticalInfo& statistical_info() { return _statistical_info; }
611
612 JFR_ONLY(DEFINE_THREAD_LOCAL_ACCESSOR_JFR;)
613
614 bool is_trace_suspend() { return (_suspend_flags & _trace_flag) != 0; }
615
616 // VM operation support
617 int vm_operation_ticket() { return ++_vm_operation_started_count; }
618 int vm_operation_completed_count() { return _vm_operation_completed_count; }
619 void increment_vm_operation_completed_count() { _vm_operation_completed_count++; }
620
621 // For tracking the heavyweight monitor the thread is pending on.
622 ObjectMonitor* current_pending_monitor() {
623 return _current_pending_monitor;
624 }
625 void set_current_pending_monitor(ObjectMonitor* monitor) {
626 _current_pending_monitor = monitor;
627 }
628 void set_current_pending_monitor_is_from_java(bool from_java) {
629 _current_pending_monitor_is_from_java = from_java;
630 }
631 bool current_pending_monitor_is_from_java() {
632 return _current_pending_monitor_is_from_java;
633 }
634
635 // For tracking the ObjectMonitor on which this thread called Object.wait()
636 ObjectMonitor* current_waiting_monitor() {
637 return _current_waiting_monitor;
638 }
639 void set_current_waiting_monitor(ObjectMonitor* monitor) {
640 _current_waiting_monitor = monitor;
641 }
642
643 // GC support
644 // Apply "f->do_oop" to all root oops in "this".
645 // Used by JavaThread::oops_do.
646 // Apply "cf->do_code_blob" (if !NULL) to all code blobs active in frames
647 virtual void oops_do(OopClosure* f, CodeBlobClosure* cf);
648
649 // Handles the parallel case for claim_threads_do.
650 private:
651 bool claim_par_threads_do(uintx claim_token);
652 public:
653 // Requires that "claim_token" is that of the current iteration.
654 // If "is_par" is false, sets the token of "this" to
655 // "claim_token", and returns "true". If "is_par" is true,
656 // uses an atomic instruction to set the current thread's token to
657 // "claim_token", if it is not already. Returns "true" iff the
658 // calling thread does the update, this indicates that the calling thread
659 // has claimed the thread in the current iteration.
660 bool claim_threads_do(bool is_par, uintx claim_token) {
661 if (!is_par) {
662 _threads_do_token = claim_token;
663 return true;
664 } else {
665 return claim_par_threads_do(claim_token);
666 }
667 }
668
669 uintx threads_do_token() const { return _threads_do_token; }
670
671 // jvmtiRedefineClasses support
672 void metadata_handles_do(void f(Metadata*));
673
674 // Used by fast lock support
675 virtual bool is_lock_owned(address adr) const;
676
677 // Check if address is in the stack of the thread (not just for locks).
678 // Warning: the method can only be used on the running thread
679 bool is_in_stack(address adr) const;
680 // Check if address is in the usable part of the stack (excludes protected
681 // guard pages)
682 bool is_in_usable_stack(address adr) const;
683
684 // Sets this thread as starting thread. Returns failure if thread
685 // creation fails due to lack of memory, too many threads etc.
686 bool set_as_starting_thread();
687
688 protected:
689 // OS data associated with the thread
690 OSThread* _osthread; // Platform-specific thread information
691
692 // Thread local resource area for temporary allocation within the VM
693 ResourceArea* _resource_area;
694
695 DEBUG_ONLY(ResourceMark* _current_resource_mark;)
696
697 // Thread local handle area for allocation of handles within the VM
698 HandleArea* _handle_area;
699 GrowableArray<Metadata*>* _metadata_handles;
700
701 // Support for stack overflow handling, get_thread, etc.
702 address _stack_base;
703 size_t _stack_size;
704 uintptr_t _self_raw_id; // used by get_thread (mutable)
705 int _lgrp_id;
706
707 volatile void** polling_page_addr() { return &_polling_page; }
708
709 public:
710 // Stack overflow support
711 address stack_base() const { assert(_stack_base != NULL,"Sanity check"); return _stack_base; }
712 void set_stack_base(address base) { _stack_base = base; }
713 size_t stack_size() const { return _stack_size; }
714 void set_stack_size(size_t size) { _stack_size = size; }
715 address stack_end() const { return stack_base() - stack_size(); }
716 void record_stack_base_and_size();
717 void register_thread_stack_with_NMT() NOT_NMT_RETURN;
718
719 bool on_local_stack(address adr) const {
720 // QQQ this has knowledge of direction, ought to be a stack method
721 return (_stack_base >= adr && adr >= stack_end());
722 }
723
724 uintptr_t self_raw_id() { return _self_raw_id; }
725 void set_self_raw_id(uintptr_t value) { _self_raw_id = value; }
726
727 int lgrp_id() const { return _lgrp_id; }
728 void set_lgrp_id(int value) { _lgrp_id = value; }
729
730 // Printing
731 void print_on(outputStream* st, bool print_extended_info) const;
732 virtual void print_on(outputStream* st) const { print_on(st, false); }
733 void print() const;
734 virtual void print_on_error(outputStream* st, char* buf, int buflen) const;
735 void print_value_on(outputStream* st) const;
736
737 // Debug-only code
738 #ifdef ASSERT
739 private:
740 // Deadlock detection support for Mutex locks. List of locks own by thread.
741 Monitor* _owned_locks;
742 // Mutex::set_owner_implementation is the only place where _owned_locks is modified,
743 // thus the friendship
744 friend class Mutex;
745 friend class Monitor;
746
747 public:
748 void print_owned_locks_on(outputStream* st) const;
749 void print_owned_locks() const { print_owned_locks_on(tty); }
750 Monitor* owned_locks() const { return _owned_locks; }
751 bool owns_locks() const { return owned_locks() != NULL; }
752 bool owns_locks_but_compiled_lock() const;
753
754 // Deadlock detection
755 bool allow_allocation() { return _allow_allocation_count == 0; }
756 ResourceMark* current_resource_mark() { return _current_resource_mark; }
757 void set_current_resource_mark(ResourceMark* rm) { _current_resource_mark = rm; }
758 #endif
759
760 void check_for_valid_safepoint_state(bool potential_vm_operation) PRODUCT_RETURN;
761
762 private:
763 volatile int _jvmti_env_iteration_count;
764
765 public:
766 void entering_jvmti_env_iteration() { ++_jvmti_env_iteration_count; }
767 void leaving_jvmti_env_iteration() { --_jvmti_env_iteration_count; }
768 bool is_inside_jvmti_env_iteration() { return _jvmti_env_iteration_count > 0; }
769
770 // Code generation
771 static ByteSize exception_file_offset() { return byte_offset_of(Thread, _exception_file); }
772 static ByteSize exception_line_offset() { return byte_offset_of(Thread, _exception_line); }
773 static ByteSize active_handles_offset() { return byte_offset_of(Thread, _active_handles); }
774
775 static ByteSize stack_base_offset() { return byte_offset_of(Thread, _stack_base); }
776 static ByteSize stack_size_offset() { return byte_offset_of(Thread, _stack_size); }
777
778 static ByteSize polling_page_offset() { return byte_offset_of(Thread, _polling_page); }
779
780 static ByteSize tlab_start_offset() { return byte_offset_of(Thread, _tlab) + ThreadLocalAllocBuffer::start_offset(); }
781 static ByteSize tlab_end_offset() { return byte_offset_of(Thread, _tlab) + ThreadLocalAllocBuffer::end_offset(); }
782 static ByteSize tlab_top_offset() { return byte_offset_of(Thread, _tlab) + ThreadLocalAllocBuffer::top_offset(); }
783 static ByteSize tlab_pf_top_offset() { return byte_offset_of(Thread, _tlab) + ThreadLocalAllocBuffer::pf_top_offset(); }
784
785 static ByteSize allocated_bytes_offset() { return byte_offset_of(Thread, _allocated_bytes); }
786
787 JFR_ONLY(DEFINE_THREAD_LOCAL_OFFSET_JFR;)
788
789 public:
790 volatile intptr_t _Stalled;
791 volatile int _TypeTag;
792 ParkEvent * _ParkEvent; // for synchronized()
793 ParkEvent * _SleepEvent; // for Thread.sleep
794 ParkEvent * _MuxEvent; // for low-level muxAcquire-muxRelease
795 int NativeSyncRecursion; // diagnostic
796
797 volatile int _OnTrap; // Resume-at IP delta
798 jint _hashStateW; // Marsaglia Shift-XOR thread-local RNG
799 jint _hashStateX; // thread-specific hashCode generator state
800 jint _hashStateY;
801 jint _hashStateZ;
802
803 // Low-level leaf-lock primitives used to implement synchronization
804 // and native monitor-mutex infrastructure.
805 // Not for general synchronization use.
806 static void SpinAcquire(volatile int * Lock, const char * Name);
807 static void SpinRelease(volatile int * Lock);
808 static void muxAcquire(volatile intptr_t * Lock, const char * Name);
809 static void muxAcquireW(volatile intptr_t * Lock, ParkEvent * ev);
810 static void muxRelease(volatile intptr_t * Lock);
811 };
812
813 // Inline implementation of Thread::current()
814 inline Thread* Thread::current() {
815 Thread* current = current_or_null();
816 assert(current != NULL, "Thread::current() called on detached thread");
817 return current;
818 }
819
820 inline Thread* Thread::current_or_null() {
821 #ifndef USE_LIBRARY_BASED_TLS_ONLY
822 return _thr_current;
823 #else
824 if (ThreadLocalStorage::is_initialized()) {
825 return ThreadLocalStorage::thread();
826 }
827 return NULL;
828 #endif
829 }
830
831 inline Thread* Thread::current_or_null_safe() {
832 if (ThreadLocalStorage::is_initialized()) {
833 return ThreadLocalStorage::thread();
834 }
835 return NULL;
836 }
837
838 class NonJavaThread: public Thread {
839 friend class VMStructs;
840
841 NonJavaThread* volatile _next;
842
843 class List;
844 static List _the_list;
845
846 void add_to_the_list();
847 void remove_from_the_list();
848
849 protected:
850 virtual void pre_run();
851 virtual void post_run();
852
853 public:
854 NonJavaThread();
855 ~NonJavaThread();
856
857 class Iterator;
858 };
859
860 // Provides iteration over the list of NonJavaThreads.
861 // List addition occurs in pre_run(), and removal occurs in post_run(),
862 // so that only live fully-initialized threads can be found in the list.
863 // Threads created after an iterator is constructed will not be visited
864 // by the iterator. The scope of an iterator is a critical section; there
865 // must be no safepoint checks in that scope.
866 class NonJavaThread::Iterator : public StackObj {
867 uint _protect_enter;
868 NonJavaThread* _current;
869
870 // Noncopyable.
871 Iterator(const Iterator&);
872 Iterator& operator=(const Iterator&);
873
874 public:
875 Iterator();
876 ~Iterator();
877
878 bool end() const { return _current == NULL; }
879 NonJavaThread* current() const { return _current; }
880 void step();
881 };
882
883 // Name support for threads. non-JavaThread subclasses with multiple
884 // uniquely named instances should derive from this.
885 class NamedThread: public NonJavaThread {
886 friend class VMStructs;
887 enum {
888 max_name_len = 64
889 };
890 private:
891 char* _name;
892 // log JavaThread being processed by oops_do
893 JavaThread* _processed_thread;
894 uint _gc_id; // The current GC id when a thread takes part in GC
895
896 public:
897 NamedThread();
898 ~NamedThread();
899 // May only be called once per thread.
900 void set_name(const char* format, ...) ATTRIBUTE_PRINTF(2, 3);
901 virtual bool is_Named_thread() const { return true; }
902 virtual char* name() const { return _name == NULL ? (char*)"Unknown Thread" : _name; }
903 JavaThread *processed_thread() { return _processed_thread; }
904 void set_processed_thread(JavaThread *thread) { _processed_thread = thread; }
905 virtual void print_on(outputStream* st) const;
906
907 void set_gc_id(uint gc_id) { _gc_id = gc_id; }
908 uint gc_id() { return _gc_id; }
909 };
910
911 // Worker threads are named and have an id of an assigned work.
912 class WorkerThread: public NamedThread {
913 private:
914 uint _id;
915 public:
916 WorkerThread() : _id(0) { }
917 virtual bool is_Worker_thread() const { return true; }
918
919 virtual WorkerThread* as_Worker_thread() const {
920 assert(is_Worker_thread(), "Dubious cast to WorkerThread*?");
921 return (WorkerThread*) this;
922 }
923
924 void set_id(uint work_id) { _id = work_id; }
925 uint id() const { return _id; }
926 };
927
928 // A single WatcherThread is used for simulating timer interrupts.
929 class WatcherThread: public NonJavaThread {
930 friend class VMStructs;
931 protected:
932 virtual void run();
933
934 private:
935 static WatcherThread* _watcher_thread;
936
937 static bool _startable;
938 // volatile due to at least one lock-free read
939 volatile static bool _should_terminate;
940 public:
941 enum SomeConstants {
942 delay_interval = 10 // interrupt delay in milliseconds
943 };
944
945 // Constructor
946 WatcherThread();
947
948 // No destruction allowed
949 ~WatcherThread() {
950 guarantee(false, "WatcherThread deletion must fix the race with VM termination");
951 }
952
953 // Tester
954 bool is_Watcher_thread() const { return true; }
955
956 // Printing
957 char* name() const { return (char*)"VM Periodic Task Thread"; }
958 void print_on(outputStream* st) const;
959 void unpark();
960
961 // Returns the single instance of WatcherThread
962 static WatcherThread* watcher_thread() { return _watcher_thread; }
963
964 // Create and start the single instance of WatcherThread, or stop it on shutdown
965 static void start();
966 static void stop();
967 // Only allow start once the VM is sufficiently initialized
968 // Otherwise the first task to enroll will trigger the start
969 static void make_startable();
970 private:
971 int sleep() const;
972 };
973
974
975 class CompilerThread;
976
977 typedef void (*ThreadFunction)(JavaThread*, TRAPS);
978
979 class JavaThread: public Thread {
980 friend class VMStructs;
981 friend class JVMCIVMStructs;
982 friend class WhiteBox;
983 private:
984 bool _on_thread_list; // Is set when this JavaThread is added to the Threads list
985 oop _threadObj; // The Java level thread object
986
987 #ifdef ASSERT
988 private:
989 int _java_call_counter;
990
991 public:
992 int java_call_counter() { return _java_call_counter; }
993 void inc_java_call_counter() { _java_call_counter++; }
994 void dec_java_call_counter() {
995 assert(_java_call_counter > 0, "Invalid nesting of JavaCallWrapper");
996 _java_call_counter--;
997 }
998 private: // restore original namespace restriction
999 #endif // ifdef ASSERT
1000
1001 #ifndef PRODUCT
1002 public:
1003 enum {
1004 jump_ring_buffer_size = 16
1005 };
1006 private: // restore original namespace restriction
1007 #endif
1008
1009 JavaFrameAnchor _anchor; // Encapsulation of current java frame and it state
1010
1011 ThreadFunction _entry_point;
1012
1013 JNIEnv _jni_environment;
1014
1015 // Deopt support
1016 DeoptResourceMark* _deopt_mark; // Holds special ResourceMark for deoptimization
1017
1018 intptr_t* _must_deopt_id; // id of frame that needs to be deopted once we
1019 // transition out of native
1020 CompiledMethod* _deopt_nmethod; // CompiledMethod that is currently being deoptimized
1021 vframeArray* _vframe_array_head; // Holds the heap of the active vframeArrays
1022 vframeArray* _vframe_array_last; // Holds last vFrameArray we popped
1023 // Because deoptimization is lazy we must save jvmti requests to set locals
1024 // in compiled frames until we deoptimize and we have an interpreter frame.
1025 // This holds the pointer to array (yeah like there might be more than one) of
1026 // description of compiled vframes that have locals that need to be updated.
1027 GrowableArray<jvmtiDeferredLocalVariableSet*>* _deferred_locals_updates;
1028
1029 // Handshake value for fixing 6243940. We need a place for the i2c
1030 // adapter to store the callee Method*. This value is NEVER live
1031 // across a gc point so it does NOT have to be gc'd
1032 // The handshake is open ended since we can't be certain that it will
1033 // be NULLed. This is because we rarely ever see the race and end up
1034 // in handle_wrong_method which is the backend of the handshake. See
1035 // code in i2c adapters and handle_wrong_method.
1036
1037 Method* _callee_target;
1038
1039 // Used to pass back results to the interpreter or generated code running Java code.
1040 oop _vm_result; // oop result is GC-preserved
1041 Metadata* _vm_result_2; // non-oop result
1042
1043 // See ReduceInitialCardMarks: this holds the precise space interval of
1044 // the most recent slow path allocation for which compiled code has
1045 // elided card-marks for performance along the fast-path.
1046 MemRegion _deferred_card_mark;
1047
1048 MonitorChunk* _monitor_chunks; // Contains the off stack monitors
1049 // allocated during deoptimization
1050 // and by JNI_MonitorEnter/Exit
1051
1052 // Async. requests support
1053 enum AsyncRequests {
1054 _no_async_condition = 0,
1055 _async_exception,
1056 _async_unsafe_access_error
1057 };
1058 AsyncRequests _special_runtime_exit_condition; // Enum indicating pending async. request
1059 oop _pending_async_exception;
1060
1061 // Safepoint support
1062 public: // Expose _thread_state for SafeFetchInt()
1063 volatile JavaThreadState _thread_state;
1064 private:
1065 ThreadSafepointState* _safepoint_state; // Holds information about a thread during a safepoint
1066 address _saved_exception_pc; // Saved pc of instruction where last implicit exception happened
1067
1068 // JavaThread termination support
1069 enum TerminatedTypes {
1070 _not_terminated = 0xDEAD - 2,
1071 _thread_exiting, // JavaThread::exit() has been called for this thread
1072 _thread_terminated, // JavaThread is removed from thread list
1073 _vm_exited // JavaThread is still executing native code, but VM is terminated
1074 // only VM_Exit can set _vm_exited
1075 };
1076
1077 // In general a JavaThread's _terminated field transitions as follows:
1078 //
1079 // _not_terminated => _thread_exiting => _thread_terminated
1080 //
1081 // _vm_exited is a special value to cover the case of a JavaThread
1082 // executing native code after the VM itself is terminated.
1083 volatile TerminatedTypes _terminated;
1084 // suspend/resume support
1085 volatile bool _suspend_equivalent; // Suspend equivalent condition
1086 jint _in_deopt_handler; // count of deoptimization
1087 // handlers thread is in
1088 volatile bool _doing_unsafe_access; // Thread may fault due to unsafe access
1089 bool _do_not_unlock_if_synchronized; // Do not unlock the receiver of a synchronized method (since it was
1090 // never locked) when throwing an exception. Used by interpreter only.
1091
1092 // JNI attach states:
1093 enum JNIAttachStates {
1094 _not_attaching_via_jni = 1, // thread is not attaching via JNI
1095 _attaching_via_jni, // thread is attaching via JNI
1096 _attached_via_jni // thread has attached via JNI
1097 };
1098
1099 // A regular JavaThread's _jni_attach_state is _not_attaching_via_jni.
1100 // A native thread that is attaching via JNI starts with a value
1101 // of _attaching_via_jni and transitions to _attached_via_jni.
1102 volatile JNIAttachStates _jni_attach_state;
1103
1104 public:
1105 // State of the stack guard pages for this thread.
1106 enum StackGuardState {
1107 stack_guard_unused, // not needed
1108 stack_guard_reserved_disabled,
1109 stack_guard_yellow_reserved_disabled,// disabled (temporarily) after stack overflow
1110 stack_guard_enabled // enabled
1111 };
1112
1113 private:
1114
1115 #if INCLUDE_JVMCI
1116 // The _pending_* fields below are used to communicate extra information
1117 // from an uncommon trap in JVMCI compiled code to the uncommon trap handler.
1118
1119 // Communicates the DeoptReason and DeoptAction of the uncommon trap
1120 int _pending_deoptimization;
1121
1122 // Specifies whether the uncommon trap is to bci 0 of a synchronized method
1123 // before the monitor has been acquired.
1124 bool _pending_monitorenter;
1125
1126 // Specifies if the DeoptReason for the last uncommon trap was Reason_transfer_to_interpreter
1127 bool _pending_transfer_to_interpreter;
1128
1129 // True if in a runtime call from compiled code that will deoptimize
1130 // and re-execute a failed heap allocation in the interpreter.
1131 bool _in_retryable_allocation;
1132
1133 // An id of a speculation that JVMCI compiled code can use to further describe and
1134 // uniquely identify the speculative optimization guarded by the uncommon trap
1135 jlong _pending_failed_speculation;
1136
1137 // These fields are mutually exclusive in terms of live ranges.
1138 union {
1139 // Communicates the pc at which the most recent implicit exception occurred
1140 // from the signal handler to a deoptimization stub.
1141 address _implicit_exception_pc;
1142
1143 // Communicates an alternative call target to an i2c stub from a JavaCall .
1144 address _alternate_call_target;
1145 } _jvmci;
1146
1147 // Support for high precision, thread sensitive counters in JVMCI compiled code.
1148 jlong* _jvmci_counters;
1149
1150 public:
1151 static jlong* _jvmci_old_thread_counters;
1152 static void collect_counters(jlong* array, int length);
1153 private:
1154 #endif // INCLUDE_JVMCI
1155
1156 StackGuardState _stack_guard_state;
1157
1158 // Precompute the limit of the stack as used in stack overflow checks.
1159 // We load it from here to simplify the stack overflow check in assembly.
1160 address _stack_overflow_limit;
1161 address _reserved_stack_activation;
1162
1163 // Compiler exception handling (NOTE: The _exception_oop is *NOT* the same as _pending_exception. It is
1164 // used to temp. parsing values into and out of the runtime system during exception handling for compiled
1165 // code)
1166 volatile oop _exception_oop; // Exception thrown in compiled code
1167 volatile address _exception_pc; // PC where exception happened
1168 volatile address _exception_handler_pc; // PC for handler of exception
1169 volatile int _is_method_handle_return; // true (== 1) if the current exception PC is a MethodHandle call site.
1170
1171 private:
1172 // support for JNI critical regions
1173 jint _jni_active_critical; // count of entries into JNI critical region
1174
1175 // Checked JNI: function name requires exception check
1176 char* _pending_jni_exception_check_fn;
1177
1178 // For deadlock detection.
1179 int _depth_first_number;
1180
1181 // JVMTI PopFrame support
1182 // This is set to popframe_pending to signal that top Java frame should be popped immediately
1183 int _popframe_condition;
1184
1185 // If reallocation of scalar replaced objects fails, we throw OOM
1186 // and during exception propagation, pop the top
1187 // _frames_to_pop_failed_realloc frames, the ones that reference
1188 // failed reallocations.
1189 int _frames_to_pop_failed_realloc;
1190
1191 #ifndef PRODUCT
1192 int _jmp_ring_index;
1193 struct {
1194 // We use intptr_t instead of address so debugger doesn't try and display strings
1195 intptr_t _target;
1196 intptr_t _instruction;
1197 const char* _file;
1198 int _line;
1199 } _jmp_ring[jump_ring_buffer_size];
1200 #endif // PRODUCT
1201
1202 friend class VMThread;
1203 friend class ThreadWaitTransition;
1204 friend class VM_Exit;
1205
1206 void initialize(); // Initialized the instance variables
1207
1208 public:
1209 // Constructor
1210 JavaThread(bool is_attaching_via_jni = false); // for main thread and JNI attached threads
1211 JavaThread(ThreadFunction entry_point, size_t stack_size = 0);
1212 ~JavaThread();
1213
1214 #ifdef ASSERT
1215 // verify this JavaThread hasn't be published in the Threads::list yet
1216 void verify_not_published();
1217 #endif
1218
1219 //JNI functiontable getter/setter for JVMTI jni function table interception API.
1220 void set_jni_functions(struct JNINativeInterface_* functionTable) {
1221 _jni_environment.functions = functionTable;
1222 }
1223 struct JNINativeInterface_* get_jni_functions() {
1224 return (struct JNINativeInterface_ *)_jni_environment.functions;
1225 }
1226
1227 // This function is called at thread creation to allow
1228 // platform specific thread variables to be initialized.
1229 void cache_global_variables();
1230
1231 // Executes Shutdown.shutdown()
1232 void invoke_shutdown_hooks();
1233
1234 // Cleanup on thread exit
1235 enum ExitType {
1236 normal_exit,
1237 jni_detach
1238 };
1239 void exit(bool destroy_vm, ExitType exit_type = normal_exit);
1240
1241 void cleanup_failed_attach_current_thread(bool is_daemon);
1242
1243 // Testers
1244 virtual bool is_Java_thread() const { return true; }
1245 virtual bool can_call_java() const { return true; }
1246
1247 // Thread oop. threadObj() can be NULL for initial JavaThread
1248 // (or for threads attached via JNI)
1249 oop threadObj() const { return _threadObj; }
1250 void set_threadObj(oop p) { _threadObj = p; }
1251
1252 ThreadPriority java_priority() const; // Read from threadObj()
1253
1254 // Prepare thread and add to priority queue. If a priority is
1255 // not specified, use the priority of the thread object. Threads_lock
1256 // must be held while this function is called.
1257 void prepare(jobject jni_thread, ThreadPriority prio=NoPriority);
1258
1259 void set_saved_exception_pc(address pc) { _saved_exception_pc = pc; }
1260 address saved_exception_pc() { return _saved_exception_pc; }
1261
1262
1263 ThreadFunction entry_point() const { return _entry_point; }
1264
1265 // Allocates a new Java level thread object for this thread. thread_name may be NULL.
1266 void allocate_threadObj(Handle thread_group, const char* thread_name, bool daemon, TRAPS);
1267
1268 // Last frame anchor routines
1269
1270 JavaFrameAnchor* frame_anchor(void) { return &_anchor; }
1271
1272 // last_Java_sp
1273 bool has_last_Java_frame() const { return _anchor.has_last_Java_frame(); }
1274 intptr_t* last_Java_sp() const { return _anchor.last_Java_sp(); }
1275
1276 // last_Java_pc
1277
1278 address last_Java_pc(void) { return _anchor.last_Java_pc(); }
1279
1280 // Safepoint support
1281 inline JavaThreadState thread_state() const;
1282 inline void set_thread_state(JavaThreadState s);
1283 inline void set_thread_state_fence(JavaThreadState s); // fence after setting thread state
1284 inline ThreadSafepointState* safepoint_state() const;
1285 inline void set_safepoint_state(ThreadSafepointState* state);
1286 inline bool is_at_poll_safepoint();
1287
1288 // JavaThread termination and lifecycle support:
1289 void smr_delete();
1290 bool on_thread_list() const { return _on_thread_list; }
1291 void set_on_thread_list() { _on_thread_list = true; }
1292
1293 // thread has called JavaThread::exit() or is terminated
1294 bool is_exiting() const;
1295 // thread is terminated (no longer on the threads list); we compare
1296 // against the two non-terminated values so that a freed JavaThread
1297 // will also be considered terminated.
1298 bool check_is_terminated(TerminatedTypes l_terminated) const {
1299 return l_terminated != _not_terminated && l_terminated != _thread_exiting;
1300 }
1301 bool is_terminated() const;
1302 void set_terminated(TerminatedTypes t);
1303 // special for Threads::remove() which is static:
1304 void set_terminated_value();
1305 void block_if_vm_exited();
1306
1307 bool doing_unsafe_access() { return _doing_unsafe_access; }
1308 void set_doing_unsafe_access(bool val) { _doing_unsafe_access = val; }
1309
1310 bool do_not_unlock_if_synchronized() { return _do_not_unlock_if_synchronized; }
1311 void set_do_not_unlock_if_synchronized(bool val) { _do_not_unlock_if_synchronized = val; }
1312
1313 inline void set_polling_page_release(void* poll_value);
1314 inline void set_polling_page(void* poll_value);
1315 inline volatile void* get_polling_page();
1316
1317 private:
1318 // Support for thread handshake operations
1319 HandshakeState _handshake;
1320 public:
1321 void set_handshake_operation(HandshakeOperation* op) {
1322 _handshake.set_operation(this, op);
1323 }
1324
1325 bool has_handshake() const {
1326 return _handshake.has_operation();
1327 }
1328
1329 void handshake_process_by_self() {
1330 _handshake.process_by_self(this);
1331 }
1332
1333 void handshake_process_by_vmthread() {
1334 _handshake.process_by_vmthread(this);
1335 }
1336
1337 // Suspend/resume support for JavaThread
1338 private:
1339 inline void set_ext_suspended();
1340 inline void clear_ext_suspended();
1341
1342 public:
1343 void java_suspend(); // higher-level suspension logic called by the public APIs
1344 void java_resume(); // higher-level resume logic called by the public APIs
1345 int java_suspend_self(); // low-level self-suspension mechanics
1346
1347 private:
1348 // mid-level wrapper around java_suspend_self to set up correct state and
1349 // check for a pending safepoint at the end
1350 void java_suspend_self_with_safepoint_check();
1351
1352 public:
1353 void check_and_wait_while_suspended() {
1354 assert(JavaThread::current() == this, "sanity check");
1355
1356 bool do_self_suspend;
1357 do {
1358 // were we externally suspended while we were waiting?
1359 do_self_suspend = handle_special_suspend_equivalent_condition();
1360 if (do_self_suspend) {
1361 // don't surprise the thread that suspended us by returning
1362 java_suspend_self();
1363 set_suspend_equivalent();
1364 }
1365 } while (do_self_suspend);
1366 }
1367 static void check_safepoint_and_suspend_for_native_trans(JavaThread *thread);
1368 // Check for async exception in addition to safepoint and suspend request.
1369 static void check_special_condition_for_native_trans(JavaThread *thread);
1370
1371 // Same as check_special_condition_for_native_trans but finishes the
1372 // transition into thread_in_Java mode so that it can potentially
1373 // block.
1374 static void check_special_condition_for_native_trans_and_transition(JavaThread *thread);
1375
1376 bool is_ext_suspend_completed(bool called_by_wait, int delay, uint32_t *bits);
1377 bool is_ext_suspend_completed_with_lock(uint32_t *bits) {
1378 MutexLocker ml(SR_lock(), Mutex::_no_safepoint_check_flag);
1379 // Warning: is_ext_suspend_completed() may temporarily drop the
1380 // SR_lock to allow the thread to reach a stable thread state if
1381 // it is currently in a transient thread state.
1382 return is_ext_suspend_completed(false /* !called_by_wait */,
1383 SuspendRetryDelay, bits);
1384 }
1385
1386 // We cannot allow wait_for_ext_suspend_completion() to run forever or
1387 // we could hang. SuspendRetryCount and SuspendRetryDelay are normally
1388 // passed as the count and delay parameters. Experiments with specific
1389 // calls to wait_for_ext_suspend_completion() can be done by passing
1390 // other values in the code. Experiments with all calls can be done
1391 // via the appropriate -XX options.
1392 bool wait_for_ext_suspend_completion(int count, int delay, uint32_t *bits);
1393
1394 // test for suspend - most (all?) of these should go away
1395 bool is_thread_fully_suspended(bool wait_for_suspend, uint32_t *bits);
1396
1397 inline void set_external_suspend();
1398 inline void clear_external_suspend();
1399
1400 bool is_external_suspend() const {
1401 return (_suspend_flags & _external_suspend) != 0;
1402 }
1403 // Whenever a thread transitions from native to vm/java it must suspend
1404 // if external|deopt suspend is present.
1405 bool is_suspend_after_native() const {
1406 return (_suspend_flags & (_external_suspend JFR_ONLY(| _trace_flag))) != 0;
1407 }
1408
1409 // external suspend request is completed
1410 bool is_ext_suspended() const {
1411 return (_suspend_flags & _ext_suspended) != 0;
1412 }
1413
1414 bool is_external_suspend_with_lock() const {
1415 MutexLocker ml(SR_lock(), Mutex::_no_safepoint_check_flag);
1416 return is_external_suspend();
1417 }
1418
1419 // Special method to handle a pending external suspend request
1420 // when a suspend equivalent condition lifts.
1421 bool handle_special_suspend_equivalent_condition() {
1422 assert(is_suspend_equivalent(),
1423 "should only be called in a suspend equivalence condition");
1424 MutexLocker ml(SR_lock(), Mutex::_no_safepoint_check_flag);
1425 bool ret = is_external_suspend();
1426 if (!ret) {
1427 // not about to self-suspend so clear suspend equivalence
1428 clear_suspend_equivalent();
1429 }
1430 // implied else:
1431 // We have a pending external suspend request so we leave the
1432 // suspend_equivalent flag set until java_suspend_self() sets
1433 // the ext_suspended flag and clears the suspend_equivalent
1434 // flag. This insures that wait_for_ext_suspend_completion()
1435 // will return consistent values.
1436 return ret;
1437 }
1438
1439 // utility methods to see if we are doing some kind of suspension
1440 bool is_being_ext_suspended() const {
1441 MutexLocker ml(SR_lock(), Mutex::_no_safepoint_check_flag);
1442 return is_ext_suspended() || is_external_suspend();
1443 }
1444
1445 bool is_suspend_equivalent() const { return _suspend_equivalent; }
1446
1447 void set_suspend_equivalent() { _suspend_equivalent = true; }
1448 void clear_suspend_equivalent() { _suspend_equivalent = false; }
1449
1450 // Thread.stop support
1451 void send_thread_stop(oop throwable);
1452 AsyncRequests clear_special_runtime_exit_condition() {
1453 AsyncRequests x = _special_runtime_exit_condition;
1454 _special_runtime_exit_condition = _no_async_condition;
1455 return x;
1456 }
1457
1458 // Are any async conditions present?
1459 bool has_async_condition() { return (_special_runtime_exit_condition != _no_async_condition); }
1460
1461 void check_and_handle_async_exceptions(bool check_unsafe_error = true);
1462
1463 // these next two are also used for self-suspension and async exception support
1464 void handle_special_runtime_exit_condition(bool check_asyncs = true);
1465
1466 // Return true if JavaThread has an asynchronous condition or
1467 // if external suspension is requested.
1468 bool has_special_runtime_exit_condition() {
1469 // Because we don't use is_external_suspend_with_lock
1470 // it is possible that we won't see an asynchronous external suspend
1471 // request that has just gotten started, i.e., SR_lock grabbed but
1472 // _external_suspend field change either not made yet or not visible
1473 // yet. However, this is okay because the request is asynchronous and
1474 // we will see the new flag value the next time through. It's also
1475 // possible that the external suspend request is dropped after
1476 // we have checked is_external_suspend(), we will recheck its value
1477 // under SR_lock in java_suspend_self().
1478 return (_special_runtime_exit_condition != _no_async_condition) ||
1479 is_external_suspend() || is_trace_suspend();
1480 }
1481
1482 void set_pending_unsafe_access_error() { _special_runtime_exit_condition = _async_unsafe_access_error; }
1483
1484 inline void set_pending_async_exception(oop e);
1485
1486 // Fast-locking support
1487 bool is_lock_owned(address adr) const;
1488
1489 // Accessors for vframe array top
1490 // The linked list of vframe arrays are sorted on sp. This means when we
1491 // unpack the head must contain the vframe array to unpack.
1492 void set_vframe_array_head(vframeArray* value) { _vframe_array_head = value; }
1493 vframeArray* vframe_array_head() const { return _vframe_array_head; }
1494
1495 // Side structure for deferring update of java frame locals until deopt occurs
1496 GrowableArray<jvmtiDeferredLocalVariableSet*>* deferred_locals() const { return _deferred_locals_updates; }
1497 void set_deferred_locals(GrowableArray<jvmtiDeferredLocalVariableSet *>* vf) { _deferred_locals_updates = vf; }
1498
1499 // These only really exist to make debugging deopt problems simpler
1500
1501 void set_vframe_array_last(vframeArray* value) { _vframe_array_last = value; }
1502 vframeArray* vframe_array_last() const { return _vframe_array_last; }
1503
1504 // The special resourceMark used during deoptimization
1505
1506 void set_deopt_mark(DeoptResourceMark* value) { _deopt_mark = value; }
1507 DeoptResourceMark* deopt_mark(void) { return _deopt_mark; }
1508
1509 intptr_t* must_deopt_id() { return _must_deopt_id; }
1510 void set_must_deopt_id(intptr_t* id) { _must_deopt_id = id; }
1511 void clear_must_deopt_id() { _must_deopt_id = NULL; }
1512
1513 void set_deopt_compiled_method(CompiledMethod* nm) { _deopt_nmethod = nm; }
1514 CompiledMethod* deopt_compiled_method() { return _deopt_nmethod; }
1515
1516 Method* callee_target() const { return _callee_target; }
1517 void set_callee_target (Method* x) { _callee_target = x; }
1518
1519 // Oop results of vm runtime calls
1520 oop vm_result() const { return _vm_result; }
1521 void set_vm_result (oop x) { _vm_result = x; }
1522
1523 Metadata* vm_result_2() const { return _vm_result_2; }
1524 void set_vm_result_2 (Metadata* x) { _vm_result_2 = x; }
1525
1526 MemRegion deferred_card_mark() const { return _deferred_card_mark; }
1527 void set_deferred_card_mark(MemRegion mr) { _deferred_card_mark = mr; }
1528
1529 #if INCLUDE_JVMCI
1530 int pending_deoptimization() const { return _pending_deoptimization; }
1531 jlong pending_failed_speculation() const { return _pending_failed_speculation; }
1532 bool has_pending_monitorenter() const { return _pending_monitorenter; }
1533 void set_pending_monitorenter(bool b) { _pending_monitorenter = b; }
1534 void set_pending_deoptimization(int reason) { _pending_deoptimization = reason; }
1535 void set_pending_failed_speculation(jlong failed_speculation) { _pending_failed_speculation = failed_speculation; }
1536 void set_pending_transfer_to_interpreter(bool b) { _pending_transfer_to_interpreter = b; }
1537 void set_jvmci_alternate_call_target(address a) { assert(_jvmci._alternate_call_target == NULL, "must be"); _jvmci._alternate_call_target = a; }
1538 void set_jvmci_implicit_exception_pc(address a) { assert(_jvmci._implicit_exception_pc == NULL, "must be"); _jvmci._implicit_exception_pc = a; }
1539
1540 virtual bool in_retryable_allocation() const { return _in_retryable_allocation; }
1541 void set_in_retryable_allocation(bool b) { _in_retryable_allocation = b; }
1542 #endif // INCLUDE_JVMCI
1543
1544 // Exception handling for compiled methods
1545 oop exception_oop() const { return _exception_oop; }
1546 address exception_pc() const { return _exception_pc; }
1547 address exception_handler_pc() const { return _exception_handler_pc; }
1548 bool is_method_handle_return() const { return _is_method_handle_return == 1; }
1549
1550 void set_exception_oop(oop o) { (void)const_cast<oop&>(_exception_oop = o); }
1551 void set_exception_pc(address a) { _exception_pc = a; }
1552 void set_exception_handler_pc(address a) { _exception_handler_pc = a; }
1553 void set_is_method_handle_return(bool value) { _is_method_handle_return = value ? 1 : 0; }
1554
1555 void clear_exception_oop_and_pc() {
1556 set_exception_oop(NULL);
1557 set_exception_pc(NULL);
1558 }
1559
1560 // Stack overflow support
1561 //
1562 // (small addresses)
1563 //
1564 // -- <-- stack_end() ---
1565 // | |
1566 // | red pages |
1567 // | |
1568 // -- <-- stack_red_zone_base() |
1569 // | |
1570 // | guard
1571 // | yellow pages zone
1572 // | |
1573 // | |
1574 // -- <-- stack_yellow_zone_base() |
1575 // | |
1576 // | |
1577 // | reserved pages |
1578 // | |
1579 // -- <-- stack_reserved_zone_base() --- ---
1580 // /|\ shadow <-- stack_overflow_limit() (somewhere in here)
1581 // | zone
1582 // \|/ size
1583 // some untouched memory ---
1584 //
1585 //
1586 // --
1587 // |
1588 // | shadow zone
1589 // |
1590 // --
1591 // x frame n
1592 // --
1593 // x frame n-1
1594 // x
1595 // --
1596 // ...
1597 //
1598 // --
1599 // x frame 0
1600 // -- <-- stack_base()
1601 //
1602 // (large addresses)
1603 //
1604
1605 private:
1606 // These values are derived from flags StackRedPages, StackYellowPages,
1607 // StackReservedPages and StackShadowPages. The zone size is determined
1608 // ergonomically if page_size > 4K.
1609 static size_t _stack_red_zone_size;
1610 static size_t _stack_yellow_zone_size;
1611 static size_t _stack_reserved_zone_size;
1612 static size_t _stack_shadow_zone_size;
1613 public:
1614 inline size_t stack_available(address cur_sp);
1615
1616 static size_t stack_red_zone_size() {
1617 assert(_stack_red_zone_size > 0, "Don't call this before the field is initialized.");
1618 return _stack_red_zone_size;
1619 }
1620 static void set_stack_red_zone_size(size_t s) {
1621 assert(is_aligned(s, os::vm_page_size()),
1622 "We can not protect if the red zone size is not page aligned.");
1623 assert(_stack_red_zone_size == 0, "This should be called only once.");
1624 _stack_red_zone_size = s;
1625 }
1626 address stack_red_zone_base() {
1627 return (address)(stack_end() + stack_red_zone_size());
1628 }
1629 bool in_stack_red_zone(address a) {
1630 return a <= stack_red_zone_base() && a >= stack_end();
1631 }
1632
1633 static size_t stack_yellow_zone_size() {
1634 assert(_stack_yellow_zone_size > 0, "Don't call this before the field is initialized.");
1635 return _stack_yellow_zone_size;
1636 }
1637 static void set_stack_yellow_zone_size(size_t s) {
1638 assert(is_aligned(s, os::vm_page_size()),
1639 "We can not protect if the yellow zone size is not page aligned.");
1640 assert(_stack_yellow_zone_size == 0, "This should be called only once.");
1641 _stack_yellow_zone_size = s;
1642 }
1643
1644 static size_t stack_reserved_zone_size() {
1645 // _stack_reserved_zone_size may be 0. This indicates the feature is off.
1646 return _stack_reserved_zone_size;
1647 }
1648 static void set_stack_reserved_zone_size(size_t s) {
1649 assert(is_aligned(s, os::vm_page_size()),
1650 "We can not protect if the reserved zone size is not page aligned.");
1651 assert(_stack_reserved_zone_size == 0, "This should be called only once.");
1652 _stack_reserved_zone_size = s;
1653 }
1654 address stack_reserved_zone_base() {
1655 return (address)(stack_end() +
1656 (stack_red_zone_size() + stack_yellow_zone_size() + stack_reserved_zone_size()));
1657 }
1658 bool in_stack_reserved_zone(address a) {
1659 return (a <= stack_reserved_zone_base()) &&
1660 (a >= (address)((intptr_t)stack_reserved_zone_base() - stack_reserved_zone_size()));
1661 }
1662
1663 static size_t stack_yellow_reserved_zone_size() {
1664 return _stack_yellow_zone_size + _stack_reserved_zone_size;
1665 }
1666 bool in_stack_yellow_reserved_zone(address a) {
1667 return (a <= stack_reserved_zone_base()) && (a >= stack_red_zone_base());
1668 }
1669
1670 // Size of red + yellow + reserved zones.
1671 static size_t stack_guard_zone_size() {
1672 return stack_red_zone_size() + stack_yellow_reserved_zone_size();
1673 }
1674
1675 static size_t stack_shadow_zone_size() {
1676 assert(_stack_shadow_zone_size > 0, "Don't call this before the field is initialized.");
1677 return _stack_shadow_zone_size;
1678 }
1679 static void set_stack_shadow_zone_size(size_t s) {
1680 // The shadow area is not allocated or protected, so
1681 // it needs not be page aligned.
1682 // But the stack bang currently assumes that it is a
1683 // multiple of page size. This guarantees that the bang
1684 // loop touches all pages in the shadow zone.
1685 // This can be guaranteed differently, as well. E.g., if
1686 // the page size is a multiple of 4K, banging in 4K steps
1687 // suffices to touch all pages. (Some pages are banged
1688 // several times, though.)
1689 assert(is_aligned(s, os::vm_page_size()),
1690 "Stack bang assumes multiple of page size.");
1691 assert(_stack_shadow_zone_size == 0, "This should be called only once.");
1692 _stack_shadow_zone_size = s;
1693 }
1694
1695 void create_stack_guard_pages();
1696 void remove_stack_guard_pages();
1697
1698 void enable_stack_reserved_zone();
1699 void disable_stack_reserved_zone();
1700 void enable_stack_yellow_reserved_zone();
1701 void disable_stack_yellow_reserved_zone();
1702 void enable_stack_red_zone();
1703 void disable_stack_red_zone();
1704
1705 inline bool stack_guard_zone_unused();
1706 inline bool stack_yellow_reserved_zone_disabled();
1707 inline bool stack_reserved_zone_disabled();
1708 inline bool stack_guards_enabled();
1709
1710 address reserved_stack_activation() const { return _reserved_stack_activation; }
1711 void set_reserved_stack_activation(address addr) {
1712 assert(_reserved_stack_activation == stack_base()
1713 || _reserved_stack_activation == NULL
1714 || addr == stack_base(), "Must not be set twice");
1715 _reserved_stack_activation = addr;
1716 }
1717
1718 // Attempt to reguard the stack after a stack overflow may have occurred.
1719 // Returns true if (a) guard pages are not needed on this thread, (b) the
1720 // pages are already guarded, or (c) the pages were successfully reguarded.
1721 // Returns false if there is not enough stack space to reguard the pages, in
1722 // which case the caller should unwind a frame and try again. The argument
1723 // should be the caller's (approximate) sp.
1724 bool reguard_stack(address cur_sp);
1725 // Similar to above but see if current stackpoint is out of the guard area
1726 // and reguard if possible.
1727 bool reguard_stack(void);
1728
1729 address stack_overflow_limit() { return _stack_overflow_limit; }
1730 void set_stack_overflow_limit() {
1731 _stack_overflow_limit =
1732 stack_end() + MAX2(JavaThread::stack_guard_zone_size(), JavaThread::stack_shadow_zone_size());
1733 }
1734
1735 // Misc. accessors/mutators
1736 void set_do_not_unlock(void) { _do_not_unlock_if_synchronized = true; }
1737 void clr_do_not_unlock(void) { _do_not_unlock_if_synchronized = false; }
1738 bool do_not_unlock(void) { return _do_not_unlock_if_synchronized; }
1739
1740 #ifndef PRODUCT
1741 void record_jump(address target, address instr, const char* file, int line);
1742 #endif // PRODUCT
1743
1744 // For assembly stub generation
1745 static ByteSize threadObj_offset() { return byte_offset_of(JavaThread, _threadObj); }
1746 #ifndef PRODUCT
1747 static ByteSize jmp_ring_index_offset() { return byte_offset_of(JavaThread, _jmp_ring_index); }
1748 static ByteSize jmp_ring_offset() { return byte_offset_of(JavaThread, _jmp_ring); }
1749 #endif // PRODUCT
1750 static ByteSize jni_environment_offset() { return byte_offset_of(JavaThread, _jni_environment); }
1751 static ByteSize pending_jni_exception_check_fn_offset() {
1752 return byte_offset_of(JavaThread, _pending_jni_exception_check_fn);
1753 }
1754 static ByteSize last_Java_sp_offset() {
1755 return byte_offset_of(JavaThread, _anchor) + JavaFrameAnchor::last_Java_sp_offset();
1756 }
1757 static ByteSize last_Java_pc_offset() {
1758 return byte_offset_of(JavaThread, _anchor) + JavaFrameAnchor::last_Java_pc_offset();
1759 }
1760 static ByteSize frame_anchor_offset() {
1761 return byte_offset_of(JavaThread, _anchor);
1762 }
1763 static ByteSize callee_target_offset() { return byte_offset_of(JavaThread, _callee_target); }
1764 static ByteSize vm_result_offset() { return byte_offset_of(JavaThread, _vm_result); }
1765 static ByteSize vm_result_2_offset() { return byte_offset_of(JavaThread, _vm_result_2); }
1766 static ByteSize thread_state_offset() { return byte_offset_of(JavaThread, _thread_state); }
1767 static ByteSize saved_exception_pc_offset() { return byte_offset_of(JavaThread, _saved_exception_pc); }
1768 static ByteSize osthread_offset() { return byte_offset_of(JavaThread, _osthread); }
1769 #if INCLUDE_JVMCI
1770 static ByteSize pending_deoptimization_offset() { return byte_offset_of(JavaThread, _pending_deoptimization); }
1771 static ByteSize pending_monitorenter_offset() { return byte_offset_of(JavaThread, _pending_monitorenter); }
1772 static ByteSize pending_failed_speculation_offset() { return byte_offset_of(JavaThread, _pending_failed_speculation); }
1773 static ByteSize jvmci_alternate_call_target_offset() { return byte_offset_of(JavaThread, _jvmci._alternate_call_target); }
1774 static ByteSize jvmci_implicit_exception_pc_offset() { return byte_offset_of(JavaThread, _jvmci._implicit_exception_pc); }
1775 static ByteSize jvmci_counters_offset() { return byte_offset_of(JavaThread, _jvmci_counters); }
1776 #endif // INCLUDE_JVMCI
1777 static ByteSize exception_oop_offset() { return byte_offset_of(JavaThread, _exception_oop); }
1778 static ByteSize exception_pc_offset() { return byte_offset_of(JavaThread, _exception_pc); }
1779 static ByteSize exception_handler_pc_offset() { return byte_offset_of(JavaThread, _exception_handler_pc); }
1780 static ByteSize stack_overflow_limit_offset() { return byte_offset_of(JavaThread, _stack_overflow_limit); }
1781 static ByteSize is_method_handle_return_offset() { return byte_offset_of(JavaThread, _is_method_handle_return); }
1782 static ByteSize stack_guard_state_offset() { return byte_offset_of(JavaThread, _stack_guard_state); }
1783 static ByteSize reserved_stack_activation_offset() { return byte_offset_of(JavaThread, _reserved_stack_activation); }
1784 static ByteSize suspend_flags_offset() { return byte_offset_of(JavaThread, _suspend_flags); }
1785
1786 static ByteSize do_not_unlock_if_synchronized_offset() { return byte_offset_of(JavaThread, _do_not_unlock_if_synchronized); }
1787 static ByteSize should_post_on_exceptions_flag_offset() {
1788 return byte_offset_of(JavaThread, _should_post_on_exceptions_flag);
1789 }
1790
1791 // Returns the jni environment for this thread
1792 JNIEnv* jni_environment() { return &_jni_environment; }
1793
1794 static JavaThread* thread_from_jni_environment(JNIEnv* env) {
1795 JavaThread *thread_from_jni_env = (JavaThread*)((intptr_t)env - in_bytes(jni_environment_offset()));
1796 // Only return NULL if thread is off the thread list; starting to
1797 // exit should not return NULL.
1798 if (thread_from_jni_env->is_terminated()) {
1799 thread_from_jni_env->block_if_vm_exited();
1800 return NULL;
1801 } else {
1802 return thread_from_jni_env;
1803 }
1804 }
1805
1806 // JNI critical regions. These can nest.
1807 bool in_critical() { return _jni_active_critical > 0; }
1808 bool in_last_critical() { return _jni_active_critical == 1; }
1809 inline void enter_critical();
1810 void exit_critical() {
1811 assert(Thread::current() == this, "this must be current thread");
1812 _jni_active_critical--;
1813 assert(_jni_active_critical >= 0, "JNI critical nesting problem?");
1814 }
1815
1816 // Checked JNI: is the programmer required to check for exceptions, if so specify
1817 // which function name. Returning to a Java frame should implicitly clear the
1818 // pending check, this is done for Native->Java transitions (i.e. user JNI code).
1819 // VM->Java transistions are not cleared, it is expected that JNI code enclosed
1820 // within ThreadToNativeFromVM makes proper exception checks (i.e. VM internal).
1821 bool is_pending_jni_exception_check() const { return _pending_jni_exception_check_fn != NULL; }
1822 void clear_pending_jni_exception_check() { _pending_jni_exception_check_fn = NULL; }
1823 const char* get_pending_jni_exception_check() const { return _pending_jni_exception_check_fn; }
1824 void set_pending_jni_exception_check(const char* fn_name) { _pending_jni_exception_check_fn = (char*) fn_name; }
1825
1826 // For deadlock detection
1827 int depth_first_number() { return _depth_first_number; }
1828 void set_depth_first_number(int dfn) { _depth_first_number = dfn; }
1829
1830 private:
1831 void set_monitor_chunks(MonitorChunk* monitor_chunks) { _monitor_chunks = monitor_chunks; }
1832
1833 public:
1834 MonitorChunk* monitor_chunks() const { return _monitor_chunks; }
1835 void add_monitor_chunk(MonitorChunk* chunk);
1836 void remove_monitor_chunk(MonitorChunk* chunk);
1837 bool in_deopt_handler() const { return _in_deopt_handler > 0; }
1838 void inc_in_deopt_handler() { _in_deopt_handler++; }
1839 void dec_in_deopt_handler() {
1840 assert(_in_deopt_handler > 0, "mismatched deopt nesting");
1841 if (_in_deopt_handler > 0) { // robustness
1842 _in_deopt_handler--;
1843 }
1844 }
1845
1846 private:
1847 void set_entry_point(ThreadFunction entry_point) { _entry_point = entry_point; }
1848
1849 public:
1850
1851 // Frame iteration; calls the function f for all frames on the stack
1852 void frames_do(void f(frame*, const RegisterMap*));
1853
1854 // Memory operations
1855 void oops_do(OopClosure* f, CodeBlobClosure* cf);
1856
1857 // Sweeper operations
1858 virtual void nmethods_do(CodeBlobClosure* cf);
1859
1860 // RedefineClasses Support
1861 void metadata_do(MetadataClosure* f);
1862
1863 // Debug method asserting thread states are correct during a handshake operation.
1864 DEBUG_ONLY(void verify_states_for_handshake();)
1865
1866 // Misc. operations
1867 char* name() const { return (char*)get_thread_name(); }
1868 void print_on(outputStream* st, bool print_extended_info) const;
1869 void print_on(outputStream* st) const { print_on(st, false); }
1870 void print() const;
1871 void print_value();
1872 void print_thread_state_on(outputStream*) const PRODUCT_RETURN;
1873 void print_thread_state() const PRODUCT_RETURN;
1874 void print_on_error(outputStream* st, char* buf, int buflen) const;
1875 void print_name_on_error(outputStream* st, char* buf, int buflen) const;
1876 void verify();
1877 const char* get_thread_name() const;
1878 protected:
1879 // factor out low-level mechanics for use in both normal and error cases
1880 virtual const char* get_thread_name_string(char* buf = NULL, int buflen = 0) const;
1881 public:
1882 const char* get_threadgroup_name() const;
1883 const char* get_parent_name() const;
1884
1885 // Accessing frames
1886 frame last_frame() {
1887 _anchor.make_walkable(this);
1888 return pd_last_frame();
1889 }
1890 javaVFrame* last_java_vframe(RegisterMap* reg_map);
1891
1892 // Returns method at 'depth' java or native frames down the stack
1893 // Used for security checks
1894 Klass* security_get_caller_class(int depth);
1895
1896 // Print stack trace in external format
1897 void print_stack_on(outputStream* st);
1898 void print_stack() { print_stack_on(tty); }
1899
1900 // Print stack traces in various internal formats
1901 void trace_stack() PRODUCT_RETURN;
1902 void trace_stack_from(vframe* start_vf) PRODUCT_RETURN;
1903 void trace_frames() PRODUCT_RETURN;
1904 void trace_oops() PRODUCT_RETURN;
1905
1906 // Print an annotated view of the stack frames
1907 void print_frame_layout(int depth = 0, bool validate_only = false) NOT_DEBUG_RETURN;
1908 void validate_frame_layout() {
1909 print_frame_layout(0, true);
1910 }
1911
1912 // Returns the number of stack frames on the stack
1913 int depth() const;
1914
1915 // Function for testing deoptimization
1916 void deoptimize();
1917 void make_zombies();
1918
1919 void deoptimized_wrt_marked_nmethods();
1920
1921 public:
1922 // Returns the running thread as a JavaThread
1923 static inline JavaThread* current();
1924
1925 // Returns the active Java thread. Do not use this if you know you are calling
1926 // from a JavaThread, as it's slower than JavaThread::current. If called from
1927 // the VMThread, it also returns the JavaThread that instigated the VMThread's
1928 // operation. You may not want that either.
1929 static JavaThread* active();
1930
1931 inline CompilerThread* as_CompilerThread();
1932
1933 protected:
1934 virtual void pre_run();
1935 virtual void run();
1936 void thread_main_inner();
1937 virtual void post_run();
1938
1939
1940 private:
1941 GrowableArray<oop>* _array_for_gc;
1942 public:
1943
1944 void register_array_for_gc(GrowableArray<oop>* array) { _array_for_gc = array; }
1945
1946 public:
1947 // Thread local information maintained by JVMTI.
1948 void set_jvmti_thread_state(JvmtiThreadState *value) { _jvmti_thread_state = value; }
1949 // A JvmtiThreadState is lazily allocated. This jvmti_thread_state()
1950 // getter is used to get this JavaThread's JvmtiThreadState if it has
1951 // one which means NULL can be returned. JvmtiThreadState::state_for()
1952 // is used to get the specified JavaThread's JvmtiThreadState if it has
1953 // one or it allocates a new JvmtiThreadState for the JavaThread and
1954 // returns it. JvmtiThreadState::state_for() will return NULL only if
1955 // the specified JavaThread is exiting.
1956 JvmtiThreadState *jvmti_thread_state() const { return _jvmti_thread_state; }
1957 static ByteSize jvmti_thread_state_offset() { return byte_offset_of(JavaThread, _jvmti_thread_state); }
1958
1959 // JVMTI PopFrame support
1960 // Setting and clearing popframe_condition
1961 // All of these enumerated values are bits. popframe_pending
1962 // indicates that a PopFrame() has been requested and not yet been
1963 // completed. popframe_processing indicates that that PopFrame() is in
1964 // the process of being completed. popframe_force_deopt_reexecution_bit
1965 // indicates that special handling is required when returning to a
1966 // deoptimized caller.
1967 enum PopCondition {
1968 popframe_inactive = 0x00,
1969 popframe_pending_bit = 0x01,
1970 popframe_processing_bit = 0x02,
1971 popframe_force_deopt_reexecution_bit = 0x04
1972 };
1973 PopCondition popframe_condition() { return (PopCondition) _popframe_condition; }
1974 void set_popframe_condition(PopCondition c) { _popframe_condition = c; }
1975 void set_popframe_condition_bit(PopCondition c) { _popframe_condition |= c; }
1976 void clear_popframe_condition() { _popframe_condition = popframe_inactive; }
1977 static ByteSize popframe_condition_offset() { return byte_offset_of(JavaThread, _popframe_condition); }
1978 bool has_pending_popframe() { return (popframe_condition() & popframe_pending_bit) != 0; }
1979 bool popframe_forcing_deopt_reexecution() { return (popframe_condition() & popframe_force_deopt_reexecution_bit) != 0; }
1980 void clear_popframe_forcing_deopt_reexecution() { _popframe_condition &= ~popframe_force_deopt_reexecution_bit; }
1981 #ifdef CC_INTERP
1982 bool pop_frame_pending(void) { return ((_popframe_condition & popframe_pending_bit) != 0); }
1983 void clr_pop_frame_pending(void) { _popframe_condition = popframe_inactive; }
1984 bool pop_frame_in_process(void) { return ((_popframe_condition & popframe_processing_bit) != 0); }
1985 void set_pop_frame_in_process(void) { _popframe_condition |= popframe_processing_bit; }
1986 void clr_pop_frame_in_process(void) { _popframe_condition &= ~popframe_processing_bit; }
1987 #endif
1988
1989 int frames_to_pop_failed_realloc() const { return _frames_to_pop_failed_realloc; }
1990 void set_frames_to_pop_failed_realloc(int nb) { _frames_to_pop_failed_realloc = nb; }
1991 void dec_frames_to_pop_failed_realloc() { _frames_to_pop_failed_realloc--; }
1992
1993 private:
1994 // Saved incoming arguments to popped frame.
1995 // Used only when popped interpreted frame returns to deoptimized frame.
1996 void* _popframe_preserved_args;
1997 int _popframe_preserved_args_size;
1998
1999 public:
2000 void popframe_preserve_args(ByteSize size_in_bytes, void* start);
2001 void* popframe_preserved_args();
2002 ByteSize popframe_preserved_args_size();
2003 WordSize popframe_preserved_args_size_in_words();
2004 void popframe_free_preserved_args();
2005
2006
2007 private:
2008 JvmtiThreadState *_jvmti_thread_state;
2009
2010 // Used by the interpreter in fullspeed mode for frame pop, method
2011 // entry, method exit and single stepping support. This field is
2012 // only set to non-zero by the VM_EnterInterpOnlyMode VM operation.
2013 // It can be set to zero asynchronously (i.e., without a VM operation
2014 // or a lock) so we have to be very careful.
2015 int _interp_only_mode;
2016
2017 public:
2018 // used by the interpreter for fullspeed debugging support (see above)
2019 static ByteSize interp_only_mode_offset() { return byte_offset_of(JavaThread, _interp_only_mode); }
2020 bool is_interp_only_mode() { return (_interp_only_mode != 0); }
2021 int get_interp_only_mode() { return _interp_only_mode; }
2022 void increment_interp_only_mode() { ++_interp_only_mode; }
2023 void decrement_interp_only_mode() { --_interp_only_mode; }
2024
2025 // support for cached flag that indicates whether exceptions need to be posted for this thread
2026 // if this is false, we can avoid deoptimizing when events are thrown
2027 // this gets set to reflect whether jvmtiExport::post_exception_throw would actually do anything
2028 private:
2029 int _should_post_on_exceptions_flag;
2030
2031 public:
2032 int should_post_on_exceptions_flag() { return _should_post_on_exceptions_flag; }
2033 void set_should_post_on_exceptions_flag(int val) { _should_post_on_exceptions_flag = val; }
2034
2035 private:
2036 ThreadStatistics *_thread_stat;
2037
2038 public:
2039 ThreadStatistics* get_thread_stat() const { return _thread_stat; }
2040
2041 // Return a blocker object for which this thread is blocked parking.
2042 oop current_park_blocker();
2043
2044 private:
2045 static size_t _stack_size_at_create;
2046
2047 public:
2048 static inline size_t stack_size_at_create(void) {
2049 return _stack_size_at_create;
2050 }
2051 static inline void set_stack_size_at_create(size_t value) {
2052 _stack_size_at_create = value;
2053 }
2054
2055 // Machine dependent stuff
2056 #include OS_CPU_HEADER(thread)
2057
2058 public:
2059 void set_blocked_on_compilation(bool value) {
2060 _blocked_on_compilation = value;
2061 }
2062
2063 bool blocked_on_compilation() {
2064 return _blocked_on_compilation;
2065 }
2066 protected:
2067 bool _blocked_on_compilation;
2068
2069
2070 // JSR166 per-thread parker
2071 private:
2072 Parker* _parker;
2073 public:
2074 Parker* parker() { return _parker; }
2075
2076 // Biased locking support
2077 private:
2078 GrowableArray<MonitorInfo*>* _cached_monitor_info;
2079 public:
2080 GrowableArray<MonitorInfo*>* cached_monitor_info() { return _cached_monitor_info; }
2081 void set_cached_monitor_info(GrowableArray<MonitorInfo*>* info) { _cached_monitor_info = info; }
2082
2083 // clearing/querying jni attach status
2084 bool is_attaching_via_jni() const { return _jni_attach_state == _attaching_via_jni; }
2085 bool has_attached_via_jni() const { return is_attaching_via_jni() || _jni_attach_state == _attached_via_jni; }
2086 inline void set_done_attaching_via_jni();
2087
2088 // Stack dump assistance:
2089 // Track the class we want to initialize but for which we have to wait
2090 // on its init_lock() because it is already being initialized.
2091 void set_class_to_be_initialized(InstanceKlass* k);
2092 InstanceKlass* class_to_be_initialized() const;
2093
2094 private:
2095 InstanceKlass* _class_to_be_initialized;
2096
2097 };
2098
2099 // Inline implementation of JavaThread::current
2100 inline JavaThread* JavaThread::current() {
2101 Thread* thread = Thread::current();
2102 assert(thread->is_Java_thread(), "just checking");
2103 return (JavaThread*)thread;
2104 }
2105
2106 inline CompilerThread* JavaThread::as_CompilerThread() {
2107 assert(is_Compiler_thread(), "just checking");
2108 return (CompilerThread*)this;
2109 }
2110
2111 // Dedicated thread to sweep the code cache
2112 class CodeCacheSweeperThread : public JavaThread {
2113 CompiledMethod* _scanned_compiled_method; // nmethod being scanned by the sweeper
2114 public:
2115 CodeCacheSweeperThread();
2116 // Track the nmethod currently being scanned by the sweeper
2117 void set_scanned_compiled_method(CompiledMethod* cm) {
2118 assert(_scanned_compiled_method == NULL || cm == NULL, "should reset to NULL before writing a new value");
2119 _scanned_compiled_method = cm;
2120 }
2121
2122 // Hide sweeper thread from external view.
2123 bool is_hidden_from_external_view() const { return true; }
2124
2125 bool is_Code_cache_sweeper_thread() const { return true; }
2126
2127 // Prevent GC from unloading _scanned_compiled_method
2128 void oops_do(OopClosure* f, CodeBlobClosure* cf);
2129 void nmethods_do(CodeBlobClosure* cf);
2130 };
2131
2132 // A thread used for Compilation.
2133 class CompilerThread : public JavaThread {
2134 friend class VMStructs;
2135 private:
2136 CompilerCounters* _counters;
2137
2138 ciEnv* _env;
2139 CompileLog* _log;
2140 CompileTask* volatile _task; // print_threads_compiling can read this concurrently.
2141 CompileQueue* _queue;
2142 BufferBlob* _buffer_blob;
2143
2144 AbstractCompiler* _compiler;
2145 TimeStamp _idle_time;
2146
2147 public:
2148
2149 static CompilerThread* current();
2150
2151 CompilerThread(CompileQueue* queue, CompilerCounters* counters);
2152 ~CompilerThread();
2153
2154 bool is_Compiler_thread() const { return true; }
2155
2156 virtual bool can_call_java() const;
2157
2158 // Hide native compiler threads from external view.
2159 bool is_hidden_from_external_view() const { return !can_call_java(); }
2160
2161 void set_compiler(AbstractCompiler* c) { _compiler = c; }
2162 AbstractCompiler* compiler() const { return _compiler; }
2163
2164 CompileQueue* queue() const { return _queue; }
2165 CompilerCounters* counters() const { return _counters; }
2166
2167 // Get/set the thread's compilation environment.
2168 ciEnv* env() { return _env; }
2169 void set_env(ciEnv* env) { _env = env; }
2170
2171 BufferBlob* get_buffer_blob() const { return _buffer_blob; }
2172 void set_buffer_blob(BufferBlob* b) { _buffer_blob = b; }
2173
2174 // Get/set the thread's logging information
2175 CompileLog* log() { return _log; }
2176 void init_log(CompileLog* log) {
2177 // Set once, for good.
2178 assert(_log == NULL, "set only once");
2179 _log = log;
2180 }
2181
2182 void start_idle_timer() { _idle_time.update(); }
2183 jlong idle_time_millis() {
2184 return TimeHelper::counter_to_millis(_idle_time.ticks_since_update());
2185 }
2186
2187 #ifndef PRODUCT
2188 private:
2189 IdealGraphPrinter *_ideal_graph_printer;
2190 public:
2191 IdealGraphPrinter *ideal_graph_printer() { return _ideal_graph_printer; }
2192 void set_ideal_graph_printer(IdealGraphPrinter *n) { _ideal_graph_printer = n; }
2193 #endif
2194
2195 // Get/set the thread's current task
2196 CompileTask* task() { return _task; }
2197 void set_task(CompileTask* task) { _task = task; }
2198 };
2199
2200 inline CompilerThread* CompilerThread::current() {
2201 return JavaThread::current()->as_CompilerThread();
2202 }
2203
2204 // The active thread queue. It also keeps track of the current used
2205 // thread priorities.
2206 class Threads: AllStatic {
2207 friend class VMStructs;
2208 private:
2209 static int _number_of_threads;
2210 static int _number_of_non_daemon_threads;
2211 static int _return_code;
2212 static uintx _thread_claim_token;
2213 #ifdef ASSERT
2214 static bool _vm_complete;
2215 #endif
2216
2217 static void initialize_java_lang_classes(JavaThread* main_thread, TRAPS);
2218 static void initialize_jsr292_core_classes(TRAPS);
2219
2220 public:
2221 // Thread management
2222 // force_daemon is a concession to JNI, where we may need to add a
2223 // thread to the thread list before allocating its thread object
2224 static void add(JavaThread* p, bool force_daemon = false);
2225 static void remove(JavaThread* p, bool is_daemon);
2226 static void non_java_threads_do(ThreadClosure* tc);
2227 static void java_threads_do(ThreadClosure* tc);
2228 static void java_threads_and_vm_thread_do(ThreadClosure* tc);
2229 static void threads_do(ThreadClosure* tc);
2230 static void possibly_parallel_threads_do(bool is_par, ThreadClosure* tc);
2231
2232 // Initializes the vm and creates the vm thread
2233 static jint create_vm(JavaVMInitArgs* args, bool* canTryAgain);
2234 static void convert_vm_init_libraries_to_agents();
2235 static void create_vm_init_libraries();
2236 static void create_vm_init_agents();
2237 static void shutdown_vm_agents();
2238 static bool destroy_vm();
2239 // Supported VM versions via JNI
2240 // Includes JNI_VERSION_1_1
2241 static jboolean is_supported_jni_version_including_1_1(jint version);
2242 // Does not include JNI_VERSION_1_1
2243 static jboolean is_supported_jni_version(jint version);
2244
2245 // The "thread claim token" provides a way for threads to be claimed
2246 // by parallel worker tasks.
2247 //
2248 // Each thread contains a "token" field. A task will claim the
2249 // thread only if its token is different from the global token,
2250 // which is updated by calling change_thread_claim_token(). When
2251 // a thread is claimed, it's token is set to the global token value
2252 // so other threads in the same iteration pass won't claim it.
2253 //
2254 // For this to work change_thread_claim_token() needs to be called
2255 // exactly once in sequential code before starting parallel tasks
2256 // that should claim threads.
2257 //
2258 // New threads get their token set to 0 and change_thread_claim_token()
2259 // never sets the global token to 0.
2260 static uintx thread_claim_token() { return _thread_claim_token; }
2261 static void change_thread_claim_token();
2262 static void assert_all_threads_claimed() NOT_DEBUG_RETURN;
2263
2264 // Apply "f->do_oop" to all root oops in all threads.
2265 // This version may only be called by sequential code.
2266 static void oops_do(OopClosure* f, CodeBlobClosure* cf);
2267 // This version may be called by sequential or parallel code.
2268 static void possibly_parallel_oops_do(bool is_par, OopClosure* f, CodeBlobClosure* cf);
2269
2270 // Apply "f->do_oop" to roots in all threads that
2271 // are part of compiled frames
2272 static void compiled_frame_oops_do(OopClosure* f, CodeBlobClosure* cf);
2273
2274 static void convert_hcode_pointers();
2275 static void restore_hcode_pointers();
2276
2277 // Sweeper
2278 static void nmethods_do(CodeBlobClosure* cf);
2279
2280 // RedefineClasses support
2281 static void metadata_do(MetadataClosure* f);
2282 static void metadata_handles_do(void f(Metadata*));
2283
2284 #ifdef ASSERT
2285 static bool is_vm_complete() { return _vm_complete; }
2286 #endif // ASSERT
2287
2288 // Verification
2289 static void verify();
2290 static void print_on(outputStream* st, bool print_stacks, bool internal_format, bool print_concurrent_locks, bool print_extended_info);
2291 static void print(bool print_stacks, bool internal_format) {
2292 // this function is only used by debug.cpp
2293 print_on(tty, print_stacks, internal_format, false /* no concurrent lock printed */, false /* simple format */);
2294 }
2295 static void print_on_error(outputStream* st, Thread* current, char* buf, int buflen);
2296 static void print_on_error(Thread* this_thread, outputStream* st, Thread* current, char* buf,
2297 int buflen, bool* found_current);
2298 static void print_threads_compiling(outputStream* st, char* buf, int buflen, bool short_form = false);
2299
2300 // Get Java threads that are waiting to enter a monitor.
2301 static GrowableArray<JavaThread*>* get_pending_threads(ThreadsList * t_list,
2302 int count, address monitor);
2303
2304 // Get owning Java thread from the monitor's owner field.
2305 static JavaThread *owning_thread_from_monitor_owner(ThreadsList * t_list,
2306 address owner);
2307
2308 // Number of threads on the active threads list
2309 static int number_of_threads() { return _number_of_threads; }
2310 // Number of non-daemon threads on the active threads list
2311 static int number_of_non_daemon_threads() { return _number_of_non_daemon_threads; }
2312
2313 // Deoptimizes all frames tied to marked nmethods
2314 static void deoptimized_wrt_marked_nmethods();
2315
2316 struct Test; // For private gtest access.
2317 };
2318
2319
2320 // Thread iterator
2321 class ThreadClosure: public StackObj {
2322 public:
2323 virtual void do_thread(Thread* thread) = 0;
2324 };
2325
2326 class SignalHandlerMark: public StackObj {
2327 private:
2328 Thread* _thread;
2329 public:
2330 SignalHandlerMark(Thread* t) {
2331 _thread = t;
2332 if (_thread) _thread->enter_signal_handler();
2333 }
2334 ~SignalHandlerMark() {
2335 if (_thread) _thread->leave_signal_handler();
2336 _thread = NULL;
2337 }
2338 };
2339
2340
2341 #endif // SHARE_RUNTIME_THREAD_HPP