1 /*
2 * Copyright (c) 1997, 2018, 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_VM_RUNTIME_THREAD_HPP
26 #define SHARE_VM_RUNTIME_THREAD_HPP
27
28 #include "jni.h"
29 #include "gc/shared/gcThreadLocalData.hpp"
30 #include "gc/shared/threadLocalAllocBuffer.hpp"
31 #include "memory/allocation.hpp"
32 #include "memory/vtBuffer.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/safepoint.hpp"
45 #include "runtime/stubRoutines.hpp"
46 #include "runtime/threadHeapSampler.hpp"
47 #include "runtime/threadLocalStorage.hpp"
48 #include "runtime/threadStatisticalInfo.hpp"
49 #include "runtime/unhandledOops.hpp"
50 #include "utilities/align.hpp"
51 #include "utilities/exceptions.hpp"
52 #include "utilities/macros.hpp"
53 #ifdef ZERO
54 # include "stack_zero.hpp"
55 #endif
56 #if INCLUDE_JFR
57 #include "jfr/support/jfrThreadExtension.hpp"
58 #endif
59
60
61 class SafeThreadsListPtr;
62 class ThreadSafepointState;
63 class ThreadsList;
64 class ThreadsSMRSupport;
65
66 class JvmtiThreadState;
67 class ThreadStatistics;
68 class ConcurrentLocksDump;
69 class ParkEvent;
70 class Parker;
71
72 class ciEnv;
73 class CompileThread;
74 class CompileLog;
75 class CompileTask;
76 class CompileQueue;
77 class CompilerCounters;
78 class vframeArray;
79
80 class DeoptResourceMark;
81 class jvmtiDeferredLocalVariableSet;
82
83 class GCTaskQueue;
84 class ThreadClosure;
85 class IdealGraphPrinter;
86
87 class Metadata;
88 template <class T, MEMFLAGS F> class ChunkedList;
89 typedef ChunkedList<Metadata*, mtInternal> MetadataOnStackBuffer;
90
91 DEBUG_ONLY(class ResourceMark;)
92
93 class WorkerThread;
94
95 // Class hierarchy
96 // - Thread
97 // - JavaThread
98 // - various subclasses eg CompilerThread, ServiceThread
99 // - NonJavaThread
100 // - NamedThread
101 // - VMThread
102 // - ConcurrentGCThread
103 // - WorkerThread
104 // - GangWorker
105 // - GCTaskThread
106 // - WatcherThread
107 // - JfrThreadSampler
108 //
109 // All Thread subclasses must be either JavaThread or NonJavaThread.
110 // This means !t->is_Java_thread() iff t is a NonJavaThread, or t is
111 // a partially constructed/destroyed Thread.
112
113 class Thread: public ThreadShadow {
114 friend class VMStructs;
115 friend class JVMCIVMStructs;
116 private:
117
118 #ifndef USE_LIBRARY_BASED_TLS_ONLY
119 // Current thread is maintained as a thread-local variable
120 static THREAD_LOCAL_DECL Thread* _thr_current;
121 #endif
122
123 private:
124 // Thread local data area available to the GC. The internal
125 // structure and contents of this data area is GC-specific.
126 // Only GC and GC barrier code should access this data area.
127 GCThreadLocalData _gc_data;
128
129 public:
130 static ByteSize gc_data_offset() {
131 return byte_offset_of(Thread, _gc_data);
132 }
133
134 template <typename T> T* gc_data() {
135 STATIC_ASSERT(sizeof(T) <= sizeof(_gc_data));
136 return reinterpret_cast<T*>(&_gc_data);
137 }
138
139 // Exception handling
140 // (Note: _pending_exception and friends are in ThreadShadow)
141 //oop _pending_exception; // pending exception for current thread
142 // const char* _exception_file; // file information for exception (debugging only)
143 // int _exception_line; // line information for exception (debugging only)
144 protected:
145 // Support for forcing alignment of thread objects for biased locking
146 void* _real_malloc_address;
147
148 // JavaThread lifecycle support:
149 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
150 friend class ScanHazardPtrGatherProtectedThreadsClosure; // for cmpxchg_threads_hazard_ptr(), get_threads_hazard_ptr(), is_hazard_ptr_tagged() access
151 friend class ScanHazardPtrGatherThreadsListClosure; // for get_threads_hazard_ptr(), untag_hazard_ptr() access
152 friend class ScanHazardPtrPrintMatchingThreadsClosure; // for get_threads_hazard_ptr(), is_hazard_ptr_tagged() access
153 friend class ThreadsSMRSupport; // for _nested_threads_hazard_ptr_cnt, _threads_hazard_ptr, _threads_list_ptr access
154
155 ThreadsList* volatile _threads_hazard_ptr;
156 SafeThreadsListPtr* _threads_list_ptr;
157 ThreadsList* cmpxchg_threads_hazard_ptr(ThreadsList* exchange_value, ThreadsList* compare_value);
158 ThreadsList* get_threads_hazard_ptr();
159 void set_threads_hazard_ptr(ThreadsList* new_list);
160 static bool is_hazard_ptr_tagged(ThreadsList* list) {
161 return (intptr_t(list) & intptr_t(1)) == intptr_t(1);
162 }
163 static ThreadsList* tag_hazard_ptr(ThreadsList* list) {
164 return (ThreadsList*)(intptr_t(list) | intptr_t(1));
165 }
166 static ThreadsList* untag_hazard_ptr(ThreadsList* list) {
167 return (ThreadsList*)(intptr_t(list) & ~intptr_t(1));
168 }
169 // This field is enabled via -XX:+EnableThreadSMRStatistics:
170 uint _nested_threads_hazard_ptr_cnt;
171 void dec_nested_threads_hazard_ptr_cnt() {
172 assert(_nested_threads_hazard_ptr_cnt != 0, "mismatched {dec,inc}_nested_threads_hazard_ptr_cnt()");
173 _nested_threads_hazard_ptr_cnt--;
174 }
175 void inc_nested_threads_hazard_ptr_cnt() {
176 _nested_threads_hazard_ptr_cnt++;
177 }
178 uint nested_threads_hazard_ptr_cnt() {
179 return _nested_threads_hazard_ptr_cnt;
180 }
181
182 public:
183 void* operator new(size_t size) throw() { return allocate(size, true); }
184 void* operator new(size_t size, const std::nothrow_t& nothrow_constant) throw() {
185 return allocate(size, false); }
186 void operator delete(void* p);
187
188 protected:
189 static void* allocate(size_t size, bool throw_excpt, MEMFLAGS flags = mtThread);
190 private:
191
192 // ***************************************************************
193 // Suspend and resume support
194 // ***************************************************************
195 //
196 // VM suspend/resume no longer exists - it was once used for various
197 // things including safepoints but was deprecated and finally removed
198 // in Java 7. Because VM suspension was considered "internal" Java-level
199 // suspension was considered "external", and this legacy naming scheme
200 // remains.
201 //
202 // External suspend/resume requests come from JVM_SuspendThread,
203 // JVM_ResumeThread, JVMTI SuspendThread, and finally JVMTI
204 // ResumeThread. External
205 // suspend requests cause _external_suspend to be set and external
206 // resume requests cause _external_suspend to be cleared.
207 // External suspend requests do not nest on top of other external
208 // suspend requests. The higher level APIs reject suspend requests
209 // for already suspended threads.
210 //
211 // The external_suspend
212 // flag is checked by has_special_runtime_exit_condition() and java thread
213 // will self-suspend when handle_special_runtime_exit_condition() is
214 // called. Most uses of the _thread_blocked state in JavaThreads are
215 // considered the same as being externally suspended; if the blocking
216 // condition lifts, the JavaThread will self-suspend. Other places
217 // where VM checks for external_suspend include:
218 // + mutex granting (do not enter monitors when thread is suspended)
219 // + state transitions from _thread_in_native
220 //
221 // In general, java_suspend() does not wait for an external suspend
222 // request to complete. When it returns, the only guarantee is that
223 // the _external_suspend field is true.
224 //
225 // wait_for_ext_suspend_completion() is used to wait for an external
226 // suspend request to complete. External suspend requests are usually
227 // followed by some other interface call that requires the thread to
228 // be quiescent, e.g., GetCallTrace(). By moving the "wait time" into
229 // the interface that requires quiescence, we give the JavaThread a
230 // chance to self-suspend before we need it to be quiescent. This
231 // improves overall suspend/query performance.
232 //
233 // _suspend_flags controls the behavior of java_ suspend/resume.
234 // It must be set under the protection of SR_lock. Read from the flag is
235 // OK without SR_lock as long as the value is only used as a hint.
236 // (e.g., check _external_suspend first without lock and then recheck
237 // inside SR_lock and finish the suspension)
238 //
239 // _suspend_flags is also overloaded for other "special conditions" so
240 // that a single check indicates whether any special action is needed
241 // eg. for async exceptions.
242 // -------------------------------------------------------------------
243 // Notes:
244 // 1. The suspend/resume logic no longer uses ThreadState in OSThread
245 // but we still update its value to keep other part of the system (mainly
246 // JVMTI) happy. ThreadState is legacy code (see notes in
247 // osThread.hpp).
248 //
249 // 2. It would be more natural if set_external_suspend() is private and
250 // part of java_suspend(), but that probably would affect the suspend/query
251 // performance. Need more investigation on this.
252
253 // suspend/resume lock: used for self-suspend
254 Monitor* _SR_lock;
255
256 protected:
257 enum SuspendFlags {
258 // NOTE: avoid using the sign-bit as cc generates different test code
259 // when the sign-bit is used, and sometimes incorrectly - see CR 6398077
260
261 _external_suspend = 0x20000000U, // thread is asked to self suspend
262 _ext_suspended = 0x40000000U, // thread has self-suspended
263 _deopt_suspend = 0x10000000U, // thread needs to self suspend for deopt
264
265 _has_async_exception = 0x00000001U, // there is a pending async exception
266 _critical_native_unlock = 0x00000002U, // Must call back to unlock JNI critical lock
267
268 _trace_flag = 0x00000004U // call tracing backend
269 };
270
271 // various suspension related flags - atomically updated
272 // overloaded for async exception checking in check_special_condition_for_native_trans.
273 volatile uint32_t _suspend_flags;
274
275 private:
276 int _num_nested_signal;
277
278 DEBUG_ONLY(bool _suspendible_thread;)
279
280 public:
281 void enter_signal_handler() { _num_nested_signal++; }
282 void leave_signal_handler() { _num_nested_signal--; }
283 bool is_inside_signal_handler() const { return _num_nested_signal > 0; }
284
285 #ifdef ASSERT
286 void set_suspendible_thread() {
287 _suspendible_thread = true;
288 }
289
290 void clear_suspendible_thread() {
291 _suspendible_thread = false;
292 }
293
294 bool is_suspendible_thread() { return _suspendible_thread; }
295 #endif
296
297 private:
298 // Active_handles points to a block of handles
299 JNIHandleBlock* _active_handles;
300
301 // One-element thread local free list
302 JNIHandleBlock* _free_handle_block;
303
304 // Point to the last handle mark
305 HandleMark* _last_handle_mark;
306
307 // The parity of the last strong_roots iteration in which this thread was
308 // claimed as a task.
309 int _oops_do_parity;
310
311 // Support for GlobalCounter
312 private:
313 volatile uintx _rcu_counter;
314 public:
315 volatile uintx* get_rcu_counter() {
316 return &_rcu_counter;
317 }
318
319 public:
320 void set_last_handle_mark(HandleMark* mark) { _last_handle_mark = mark; }
321 HandleMark* last_handle_mark() const { return _last_handle_mark; }
322 private:
323
324 // debug support for checking if code does allow safepoints or not
325 // GC points in the VM can happen because of allocation, invoking a VM operation, or blocking on
326 // mutex, or blocking on an object synchronizer (Java locking).
327 // If !allow_safepoint(), then an assertion failure will happen in any of the above cases
328 // If !allow_allocation(), then an assertion failure will happen during allocation
329 // (Hence, !allow_safepoint() => !allow_allocation()).
330 //
331 // The two classes NoSafepointVerifier and No_Allocation_Verifier are used to set these counters.
332 //
333 NOT_PRODUCT(int _allow_safepoint_count;) // If 0, thread allow a safepoint to happen
334 debug_only(int _allow_allocation_count;) // If 0, the thread is allowed to allocate oops.
335
336 // Used by SkipGCALot class.
337 NOT_PRODUCT(bool _skip_gcalot;) // Should we elide gc-a-lot?
338
339 friend class NoAllocVerifier;
340 friend class NoSafepointVerifier;
341 friend class PauseNoSafepointVerifier;
342 friend class GCLocker;
343
344 volatile void* _polling_page; // Thread local polling page
345
346 ThreadLocalAllocBuffer _tlab; // Thread-local eden
347 jlong _allocated_bytes; // Cumulative number of bytes allocated on
348 // the Java heap
349 ThreadHeapSampler _heap_sampler; // For use when sampling the memory.
350
351 ThreadStatisticalInfo _statistical_info; // Statistics about the thread
352
353 JFR_ONLY(DEFINE_THREAD_LOCAL_FIELD_JFR;) // Thread-local data for jfr
354
355 int _vm_operation_started_count; // VM_Operation support
356 int _vm_operation_completed_count; // VM_Operation support
357
358 ObjectMonitor* _current_pending_monitor; // ObjectMonitor this thread
359 // is waiting to lock
360 bool _current_pending_monitor_is_from_java; // locking is from Java code
361
362 // ObjectMonitor on which this thread called Object.wait()
363 ObjectMonitor* _current_waiting_monitor;
364
365 // Private thread-local objectmonitor list - a simple cache organized as a SLL.
366 public:
367 ObjectMonitor* omFreeList;
368 int omFreeCount; // length of omFreeList
369 int omFreeProvision; // reload chunk size
370 ObjectMonitor* omInUseList; // SLL to track monitors in circulation
371 int omInUseCount; // length of omInUseList
372
373 #ifdef ASSERT
374 private:
375 bool _visited_for_critical_count;
376
377 public:
378 void set_visited_for_critical_count(bool z) { _visited_for_critical_count = z; }
379 bool was_visited_for_critical_count() const { return _visited_for_critical_count; }
380 #endif
381
382 public:
383 enum {
384 is_definitely_current_thread = true
385 };
386
387 private:
388 friend class BufferedValuesDealiaser;
389
390 BufferedValuesDealiaser* _buffered_values_dealiaser;
391 public:
392 BufferedValuesDealiaser* buffered_values_dealiaser() {
393 assert(Thread::current() == this, "Should only be accessed locally");
394 return _buffered_values_dealiaser;
395 }
396
397 // Constructor
398 Thread();
399 virtual ~Thread() = 0; // Thread is abstract.
400
401 // Manage Thread::current()
402 void initialize_thread_current();
403 void clear_thread_current(); // TLS cleanup needed before threads terminate
404
405 public:
406 // thread entry point
407 virtual void run();
408
409 // Testers
410 virtual bool is_VM_thread() const { return false; }
411 virtual bool is_Java_thread() const { return false; }
412 virtual bool is_Compiler_thread() const { return false; }
413 virtual bool is_Code_cache_sweeper_thread() const { return false; }
414 virtual bool is_hidden_from_external_view() const { return false; }
415 virtual bool is_jvmti_agent_thread() const { return false; }
416 // True iff the thread can perform GC operations at a safepoint.
417 // Generally will be true only of VM thread and parallel GC WorkGang
418 // threads.
419 virtual bool is_GC_task_thread() const { return false; }
420 virtual bool is_Watcher_thread() const { return false; }
421 virtual bool is_ConcurrentGC_thread() const { return false; }
422 virtual bool is_Named_thread() const { return false; }
423 virtual bool is_Worker_thread() const { return false; }
424
425 // Can this thread make Java upcalls
426 virtual bool can_call_java() const { return false; }
427
428 // Casts
429 virtual WorkerThread* as_Worker_thread() const { return NULL; }
430
431 virtual char* name() const { return (char*)"Unknown thread"; }
432
433 // Returns the current thread (ASSERTS if NULL)
434 static inline Thread* current();
435 // Returns the current thread, or NULL if not attached
436 static inline Thread* current_or_null();
437 // Returns the current thread, or NULL if not attached, and is
438 // safe for use from signal-handlers
439 static inline Thread* current_or_null_safe();
440
441 // Common thread operations
442 #ifdef ASSERT
443 static void check_for_dangling_thread_pointer(Thread *thread);
444 #endif
445 static void set_priority(Thread* thread, ThreadPriority priority);
446 static ThreadPriority get_priority(const Thread* const thread);
447 static void start(Thread* thread);
448 static void interrupt(Thread* thr);
449 static bool is_interrupted(Thread* thr, bool clear_interrupted);
450
451 void set_native_thread_name(const char *name) {
452 assert(Thread::current() == this, "set_native_thread_name can only be called on the current thread");
453 os::set_native_thread_name(name);
454 }
455
456 ObjectMonitor** omInUseList_addr() { return (ObjectMonitor **)&omInUseList; }
457 Monitor* SR_lock() const { return _SR_lock; }
458
459 bool has_async_exception() const { return (_suspend_flags & _has_async_exception) != 0; }
460
461 inline void set_suspend_flag(SuspendFlags f);
462 inline void clear_suspend_flag(SuspendFlags f);
463
464 inline void set_has_async_exception();
465 inline void clear_has_async_exception();
466
467 bool do_critical_native_unlock() const { return (_suspend_flags & _critical_native_unlock) != 0; }
468
469 inline void set_critical_native_unlock();
470 inline void clear_critical_native_unlock();
471
472 inline void set_trace_flag();
473 inline void clear_trace_flag();
474
475 // Support for Unhandled Oop detection
476 // Add the field for both, fastdebug and debug, builds to keep
477 // Thread's fields layout the same.
478 // Note: CHECK_UNHANDLED_OOPS is defined only for fastdebug build.
479 #ifdef CHECK_UNHANDLED_OOPS
480 private:
481 UnhandledOops* _unhandled_oops;
482 #elif defined(ASSERT)
483 private:
484 void* _unhandled_oops;
485 #endif
486 #ifdef CHECK_UNHANDLED_OOPS
487 public:
488 UnhandledOops* unhandled_oops() { return _unhandled_oops; }
489 // Mark oop safe for gc. It may be stack allocated but won't move.
490 void allow_unhandled_oop(oop *op) {
491 if (CheckUnhandledOops) unhandled_oops()->allow_unhandled_oop(op);
492 }
493 // Clear oops at safepoint so crashes point to unhandled oop violator
494 void clear_unhandled_oops() {
495 if (CheckUnhandledOops) unhandled_oops()->clear_unhandled_oops();
496 }
497 #endif // CHECK_UNHANDLED_OOPS
498
499 public:
500 #ifndef PRODUCT
501 bool skip_gcalot() { return _skip_gcalot; }
502 void set_skip_gcalot(bool v) { _skip_gcalot = v; }
503 #endif
504
505 // Installs a pending exception to be inserted later
506 static void send_async_exception(oop thread_oop, oop java_throwable);
507
508 // Resource area
509 ResourceArea* resource_area() const { return _resource_area; }
510 void set_resource_area(ResourceArea* area) { _resource_area = area; }
511
512 OSThread* osthread() const { return _osthread; }
513 void set_osthread(OSThread* thread) { _osthread = thread; }
514
515 // JNI handle support
516 JNIHandleBlock* active_handles() const { return _active_handles; }
517 void set_active_handles(JNIHandleBlock* block) { _active_handles = block; }
518 JNIHandleBlock* free_handle_block() const { return _free_handle_block; }
519 void set_free_handle_block(JNIHandleBlock* block) { _free_handle_block = block; }
520
521 // Internal handle support
522 HandleArea* handle_area() const { return _handle_area; }
523 void set_handle_area(HandleArea* area) { _handle_area = area; }
524
525 GrowableArray<Metadata*>* metadata_handles() const { return _metadata_handles; }
526 void set_metadata_handles(GrowableArray<Metadata*>* handles){ _metadata_handles = handles; }
527
528 // Thread-Local Allocation Buffer (TLAB) support
529 ThreadLocalAllocBuffer& tlab() { return _tlab; }
530 void initialize_tlab() {
531 if (UseTLAB) {
532 tlab().initialize();
533 }
534 }
535
536 jlong allocated_bytes() { return _allocated_bytes; }
537 void set_allocated_bytes(jlong value) { _allocated_bytes = value; }
538 void incr_allocated_bytes(jlong size) { _allocated_bytes += size; }
539 inline jlong cooked_allocated_bytes();
540
541 ThreadHeapSampler& heap_sampler() { return _heap_sampler; }
542
543 ThreadStatisticalInfo& statistical_info() { return _statistical_info; }
544
545 JFR_ONLY(DEFINE_THREAD_LOCAL_ACCESSOR_JFR;)
546
547 bool is_trace_suspend() { return (_suspend_flags & _trace_flag) != 0; }
548
549 // VM operation support
550 int vm_operation_ticket() { return ++_vm_operation_started_count; }
551 int vm_operation_completed_count() { return _vm_operation_completed_count; }
552 void increment_vm_operation_completed_count() { _vm_operation_completed_count++; }
553
554 // For tracking the heavyweight monitor the thread is pending on.
555 ObjectMonitor* current_pending_monitor() {
556 return _current_pending_monitor;
557 }
558 void set_current_pending_monitor(ObjectMonitor* monitor) {
559 _current_pending_monitor = monitor;
560 }
561 void set_current_pending_monitor_is_from_java(bool from_java) {
562 _current_pending_monitor_is_from_java = from_java;
563 }
564 bool current_pending_monitor_is_from_java() {
565 return _current_pending_monitor_is_from_java;
566 }
567
568 // For tracking the ObjectMonitor on which this thread called Object.wait()
569 ObjectMonitor* current_waiting_monitor() {
570 return _current_waiting_monitor;
571 }
572 void set_current_waiting_monitor(ObjectMonitor* monitor) {
573 _current_waiting_monitor = monitor;
574 }
575
576 // GC support
577 // Apply "f->do_oop" to all root oops in "this".
578 // Used by JavaThread::oops_do.
579 // Apply "cf->do_code_blob" (if !NULL) to all code blobs active in frames
580 virtual void oops_do(OopClosure* f, CodeBlobClosure* cf);
581
582 // Handles the parallel case for the method below.
583 private:
584 bool claim_oops_do_par_case(int collection_parity);
585 public:
586 // Requires that "collection_parity" is that of the current roots
587 // iteration. If "is_par" is false, sets the parity of "this" to
588 // "collection_parity", and returns "true". If "is_par" is true,
589 // uses an atomic instruction to set the current threads parity to
590 // "collection_parity", if it is not already. Returns "true" iff the
591 // calling thread does the update, this indicates that the calling thread
592 // has claimed the thread's stack as a root groop in the current
593 // collection.
594 bool claim_oops_do(bool is_par, int collection_parity) {
595 if (!is_par) {
596 _oops_do_parity = collection_parity;
597 return true;
598 } else {
599 return claim_oops_do_par_case(collection_parity);
600 }
601 }
602
603 // jvmtiRedefineClasses support
604 void metadata_handles_do(void f(Metadata*));
605
606 // Used by fast lock support
607 virtual bool is_lock_owned(address adr) const;
608
609 // Check if address is in the stack of the thread (not just for locks).
610 // Warning: the method can only be used on the running thread
611 bool is_in_stack(address adr) const;
612 // Check if address is in the usable part of the stack (excludes protected
613 // guard pages)
614 bool is_in_usable_stack(address adr) const;
615
616 // Sets this thread as starting thread. Returns failure if thread
617 // creation fails due to lack of memory, too many threads etc.
618 bool set_as_starting_thread();
619
620 protected:
621 // OS data associated with the thread
622 OSThread* _osthread; // Platform-specific thread information
623
624 // Thread local resource area for temporary allocation within the VM
625 ResourceArea* _resource_area;
626
627 DEBUG_ONLY(ResourceMark* _current_resource_mark;)
628
629 // Thread local handle area for allocation of handles within the VM
630 HandleArea* _handle_area;
631 GrowableArray<Metadata*>* _metadata_handles;
632
633 // Support for stack overflow handling, get_thread, etc.
634 address _stack_base;
635 size_t _stack_size;
636 uintptr_t _self_raw_id; // used by get_thread (mutable)
637 int _lgrp_id;
638
639 volatile void** polling_page_addr() { return &_polling_page; }
640
641 public:
642 // Stack overflow support
643 address stack_base() const { assert(_stack_base != NULL,"Sanity check"); return _stack_base; }
644 void set_stack_base(address base) { _stack_base = base; }
645 size_t stack_size() const { return _stack_size; }
646 void set_stack_size(size_t size) { _stack_size = size; }
647 address stack_end() const { return stack_base() - stack_size(); }
648 void record_stack_base_and_size();
649
650 bool on_local_stack(address adr) const {
651 // QQQ this has knowledge of direction, ought to be a stack method
652 return (_stack_base >= adr && adr >= stack_end());
653 }
654
655 uintptr_t self_raw_id() { return _self_raw_id; }
656 void set_self_raw_id(uintptr_t value) { _self_raw_id = value; }
657
658 int lgrp_id() const { return _lgrp_id; }
659 void set_lgrp_id(int value) { _lgrp_id = value; }
660
661 // Printing
662 void print_on(outputStream* st, bool print_extended_info) const;
663 virtual void print_on(outputStream* st) const { print_on(st, false); }
664 void print() const { print_on(tty); }
665 virtual void print_on_error(outputStream* st, char* buf, int buflen) const;
666 void print_value_on(outputStream* st) const;
667
668 // Debug-only code
669 #ifdef ASSERT
670 private:
671 // Deadlock detection support for Mutex locks. List of locks own by thread.
672 Monitor* _owned_locks;
673 // Mutex::set_owner_implementation is the only place where _owned_locks is modified,
674 // thus the friendship
675 friend class Mutex;
676 friend class Monitor;
677
678 public:
679 void print_owned_locks_on(outputStream* st) const;
680 void print_owned_locks() const { print_owned_locks_on(tty); }
681 Monitor* owned_locks() const { return _owned_locks; }
682 bool owns_locks() const { return owned_locks() != NULL; }
683 bool owns_locks_but_compiled_lock() const;
684 int oops_do_parity() const { return _oops_do_parity; }
685
686 // Deadlock detection
687 bool allow_allocation() { return _allow_allocation_count == 0; }
688 ResourceMark* current_resource_mark() { return _current_resource_mark; }
689 void set_current_resource_mark(ResourceMark* rm) { _current_resource_mark = rm; }
690 #endif
691
692 void check_for_valid_safepoint_state(bool potential_vm_operation) PRODUCT_RETURN;
693
694 private:
695 volatile int _jvmti_env_iteration_count;
696
697 public:
698 void entering_jvmti_env_iteration() { ++_jvmti_env_iteration_count; }
699 void leaving_jvmti_env_iteration() { --_jvmti_env_iteration_count; }
700 bool is_inside_jvmti_env_iteration() { return _jvmti_env_iteration_count > 0; }
701
702 // Code generation
703 static ByteSize exception_file_offset() { return byte_offset_of(Thread, _exception_file); }
704 static ByteSize exception_line_offset() { return byte_offset_of(Thread, _exception_line); }
705 static ByteSize active_handles_offset() { return byte_offset_of(Thread, _active_handles); }
706
707 static ByteSize stack_base_offset() { return byte_offset_of(Thread, _stack_base); }
708 static ByteSize stack_size_offset() { return byte_offset_of(Thread, _stack_size); }
709
710 static ByteSize polling_page_offset() { return byte_offset_of(Thread, _polling_page); }
711
712 #define TLAB_FIELD_OFFSET(name) \
713 static ByteSize tlab_##name##_offset() { return byte_offset_of(Thread, _tlab) + ThreadLocalAllocBuffer::name##_offset(); }
714
715 TLAB_FIELD_OFFSET(start)
716 TLAB_FIELD_OFFSET(end)
717 TLAB_FIELD_OFFSET(top)
718 TLAB_FIELD_OFFSET(pf_top)
719 TLAB_FIELD_OFFSET(size) // desired_size
720 TLAB_FIELD_OFFSET(refill_waste_limit)
721 TLAB_FIELD_OFFSET(number_of_refills)
722 TLAB_FIELD_OFFSET(fast_refill_waste)
723 TLAB_FIELD_OFFSET(slow_allocations)
724
725 #undef TLAB_FIELD_OFFSET
726
727 static ByteSize allocated_bytes_offset() { return byte_offset_of(Thread, _allocated_bytes); }
728
729 JFR_ONLY(DEFINE_THREAD_LOCAL_OFFSET_JFR;)
730
731 public:
732 volatile intptr_t _Stalled;
733 volatile int _TypeTag;
734 ParkEvent * _ParkEvent; // for synchronized()
735 ParkEvent * _SleepEvent; // for Thread.sleep
736 ParkEvent * _MutexEvent; // for native internal Mutex/Monitor
737 ParkEvent * _MuxEvent; // for low-level muxAcquire-muxRelease
738 int NativeSyncRecursion; // diagnostic
739
740 volatile int _OnTrap; // Resume-at IP delta
741 jint _hashStateW; // Marsaglia Shift-XOR thread-local RNG
742 jint _hashStateX; // thread-specific hashCode generator state
743 jint _hashStateY;
744 jint _hashStateZ;
745
746 volatile jint rng[4]; // RNG for spin loop
747
748 // Low-level leaf-lock primitives used to implement synchronization
749 // and native monitor-mutex infrastructure.
750 // Not for general synchronization use.
751 static void SpinAcquire(volatile int * Lock, const char * Name);
752 static void SpinRelease(volatile int * Lock);
753 static void muxAcquire(volatile intptr_t * Lock, const char * Name);
754 static void muxAcquireW(volatile intptr_t * Lock, ParkEvent * ev);
755 static void muxRelease(volatile intptr_t * Lock);
756 };
757
758 // Inline implementation of Thread::current()
759 inline Thread* Thread::current() {
760 Thread* current = current_or_null();
761 assert(current != NULL, "Thread::current() called on detached thread");
762 return current;
763 }
764
765 inline Thread* Thread::current_or_null() {
766 #ifndef USE_LIBRARY_BASED_TLS_ONLY
767 return _thr_current;
768 #else
769 if (ThreadLocalStorage::is_initialized()) {
770 return ThreadLocalStorage::thread();
771 }
772 return NULL;
773 #endif
774 }
775
776 inline Thread* Thread::current_or_null_safe() {
777 if (ThreadLocalStorage::is_initialized()) {
778 return ThreadLocalStorage::thread();
779 }
780 return NULL;
781 }
782
783 class NonJavaThread: public Thread {
784 friend class VMStructs;
785
786 NonJavaThread* volatile _next;
787
788 class List;
789 static List _the_list;
790
791 public:
792 NonJavaThread();
793 ~NonJavaThread();
794
795 class Iterator;
796 };
797
798 // Provides iteration over the list of NonJavaThreads. Because list
799 // management occurs in the NonJavaThread constructor and destructor,
800 // entries in the list may not be fully constructed instances of a
801 // derived class. Threads created after an iterator is constructed
802 // will not be visited by the iterator. The scope of an iterator is a
803 // critical section; there must be no safepoint checks in that scope.
804 class NonJavaThread::Iterator : public StackObj {
805 uint _protect_enter;
806 NonJavaThread* _current;
807
808 // Noncopyable.
809 Iterator(const Iterator&);
810 Iterator& operator=(const Iterator&);
811
812 public:
813 Iterator();
814 ~Iterator();
815
816 bool end() const { return _current == NULL; }
817 NonJavaThread* current() const { return _current; }
818 void step();
819 };
820
821 // Name support for threads. non-JavaThread subclasses with multiple
822 // uniquely named instances should derive from this.
823 class NamedThread: public NonJavaThread {
824 friend class VMStructs;
825 enum {
826 max_name_len = 64
827 };
828 private:
829 char* _name;
830 // log JavaThread being processed by oops_do
831 JavaThread* _processed_thread;
832 uint _gc_id; // The current GC id when a thread takes part in GC
833
834 public:
835 NamedThread();
836 ~NamedThread();
837 // May only be called once per thread.
838 void set_name(const char* format, ...) ATTRIBUTE_PRINTF(2, 3);
839 void initialize_named_thread();
840 virtual bool is_Named_thread() const { return true; }
841 virtual char* name() const { return _name == NULL ? (char*)"Unknown Thread" : _name; }
842 JavaThread *processed_thread() { return _processed_thread; }
843 void set_processed_thread(JavaThread *thread) { _processed_thread = thread; }
844 virtual void print_on(outputStream* st) const;
845
846 void set_gc_id(uint gc_id) { _gc_id = gc_id; }
847 uint gc_id() { return _gc_id; }
848 };
849
850 // Worker threads are named and have an id of an assigned work.
851 class WorkerThread: public NamedThread {
852 private:
853 uint _id;
854 public:
855 WorkerThread() : _id(0) { }
856 virtual bool is_Worker_thread() const { return true; }
857
858 virtual WorkerThread* as_Worker_thread() const {
859 assert(is_Worker_thread(), "Dubious cast to WorkerThread*?");
860 return (WorkerThread*) this;
861 }
862
863 void set_id(uint work_id) { _id = work_id; }
864 uint id() const { return _id; }
865 };
866
867 // A single WatcherThread is used for simulating timer interrupts.
868 class WatcherThread: public NonJavaThread {
869 friend class VMStructs;
870 public:
871 virtual void run();
872
873 private:
874 static WatcherThread* _watcher_thread;
875
876 static bool _startable;
877 // volatile due to at least one lock-free read
878 volatile static bool _should_terminate;
879 public:
880 enum SomeConstants {
881 delay_interval = 10 // interrupt delay in milliseconds
882 };
883
884 // Constructor
885 WatcherThread();
886
887 // No destruction allowed
888 ~WatcherThread() {
889 guarantee(false, "WatcherThread deletion must fix the race with VM termination");
890 }
891
892 // Tester
893 bool is_Watcher_thread() const { return true; }
894
895 // Printing
896 char* name() const { return (char*)"VM Periodic Task Thread"; }
897 void print_on(outputStream* st) const;
898 void unpark();
899
900 // Returns the single instance of WatcherThread
901 static WatcherThread* watcher_thread() { return _watcher_thread; }
902
903 // Create and start the single instance of WatcherThread, or stop it on shutdown
904 static void start();
905 static void stop();
906 // Only allow start once the VM is sufficiently initialized
907 // Otherwise the first task to enroll will trigger the start
908 static void make_startable();
909 private:
910 int sleep() const;
911 };
912
913
914 class CompilerThread;
915
916 typedef void (*ThreadFunction)(JavaThread*, TRAPS);
917
918 class JavaThread: public Thread {
919 friend class VMStructs;
920 friend class JVMCIVMStructs;
921 friend class WhiteBox;
922 friend class VTBuffer;
923 private:
924 JavaThread* _next; // The next thread in the Threads list
925 bool _on_thread_list; // Is set when this JavaThread is added to the Threads list
926 oop _threadObj; // The Java level thread object
927
928 #ifdef ASSERT
929 private:
930 int _java_call_counter;
931
932 public:
933 int java_call_counter() { return _java_call_counter; }
934 void inc_java_call_counter() { _java_call_counter++; }
935 void dec_java_call_counter() {
936 assert(_java_call_counter > 0, "Invalid nesting of JavaCallWrapper");
937 _java_call_counter--;
938 }
939 private: // restore original namespace restriction
940 #endif // ifdef ASSERT
941
942 #ifndef PRODUCT
943 public:
944 enum {
945 jump_ring_buffer_size = 16
946 };
947 private: // restore original namespace restriction
948 #endif
949
950 JavaFrameAnchor _anchor; // Encapsulation of current java frame and it state
951
952 ThreadFunction _entry_point;
953
954 JNIEnv _jni_environment;
955
956 // Deopt support
957 DeoptResourceMark* _deopt_mark; // Holds special ResourceMark for deoptimization
958
959 intptr_t* _must_deopt_id; // id of frame that needs to be deopted once we
960 // transition out of native
961 CompiledMethod* _deopt_nmethod; // CompiledMethod that is currently being deoptimized
962 vframeArray* _vframe_array_head; // Holds the heap of the active vframeArrays
963 vframeArray* _vframe_array_last; // Holds last vFrameArray we popped
964 // Because deoptimization is lazy we must save jvmti requests to set locals
965 // in compiled frames until we deoptimize and we have an interpreter frame.
966 // This holds the pointer to array (yeah like there might be more than one) of
967 // description of compiled vframes that have locals that need to be updated.
968 GrowableArray<jvmtiDeferredLocalVariableSet*>* _deferred_locals_updates;
969
970 // Handshake value for fixing 6243940. We need a place for the i2c
971 // adapter to store the callee Method*. This value is NEVER live
972 // across a gc point so it does NOT have to be gc'd
973 // The handshake is open ended since we can't be certain that it will
974 // be NULLed. This is because we rarely ever see the race and end up
975 // in handle_wrong_method which is the backend of the handshake. See
976 // code in i2c adapters and handle_wrong_method.
977
978 Method* _callee_target;
979
980 // Used to pass back results to the interpreter or generated code running Java code.
981 oop _vm_result; // oop result is GC-preserved
982 Metadata* _vm_result_2; // non-oop result
983 oop _return_buffered_value; // buffered value being returned
984
985 // See ReduceInitialCardMarks: this holds the precise space interval of
986 // the most recent slow path allocation for which compiled code has
987 // elided card-marks for performance along the fast-path.
988 MemRegion _deferred_card_mark;
989
990 MonitorChunk* _monitor_chunks; // Contains the off stack monitors
991 // allocated during deoptimization
992 // and by JNI_MonitorEnter/Exit
993
994 // Async. requests support
995 enum AsyncRequests {
996 _no_async_condition = 0,
997 _async_exception,
998 _async_unsafe_access_error
999 };
1000 AsyncRequests _special_runtime_exit_condition; // Enum indicating pending async. request
1001 oop _pending_async_exception;
1002
1003 // Safepoint support
1004 public: // Expose _thread_state for SafeFetchInt()
1005 volatile JavaThreadState _thread_state;
1006 private:
1007 ThreadSafepointState *_safepoint_state; // Holds information about a thread during a safepoint
1008 address _saved_exception_pc; // Saved pc of instruction where last implicit exception happened
1009
1010 // JavaThread termination support
1011 enum TerminatedTypes {
1012 _not_terminated = 0xDEAD - 2,
1013 _thread_exiting, // JavaThread::exit() has been called for this thread
1014 _thread_terminated, // JavaThread is removed from thread list
1015 _vm_exited // JavaThread is still executing native code, but VM is terminated
1016 // only VM_Exit can set _vm_exited
1017 };
1018
1019 // In general a JavaThread's _terminated field transitions as follows:
1020 //
1021 // _not_terminated => _thread_exiting => _thread_terminated
1022 //
1023 // _vm_exited is a special value to cover the case of a JavaThread
1024 // executing native code after the VM itself is terminated.
1025 volatile TerminatedTypes _terminated;
1026 // suspend/resume support
1027 volatile bool _suspend_equivalent; // Suspend equivalent condition
1028 jint _in_deopt_handler; // count of deoptimization
1029 // handlers thread is in
1030 volatile bool _doing_unsafe_access; // Thread may fault due to unsafe access
1031 bool _do_not_unlock_if_synchronized; // Do not unlock the receiver of a synchronized method (since it was
1032 // never locked) when throwing an exception. Used by interpreter only.
1033
1034 // JNI attach states:
1035 enum JNIAttachStates {
1036 _not_attaching_via_jni = 1, // thread is not attaching via JNI
1037 _attaching_via_jni, // thread is attaching via JNI
1038 _attached_via_jni // thread has attached via JNI
1039 };
1040
1041 // A regular JavaThread's _jni_attach_state is _not_attaching_via_jni.
1042 // A native thread that is attaching via JNI starts with a value
1043 // of _attaching_via_jni and transitions to _attached_via_jni.
1044 volatile JNIAttachStates _jni_attach_state;
1045
1046 public:
1047 // State of the stack guard pages for this thread.
1048 enum StackGuardState {
1049 stack_guard_unused, // not needed
1050 stack_guard_reserved_disabled,
1051 stack_guard_yellow_reserved_disabled,// disabled (temporarily) after stack overflow
1052 stack_guard_enabled // enabled
1053 };
1054
1055 private:
1056
1057 #if INCLUDE_JVMCI
1058 // The _pending_* fields below are used to communicate extra information
1059 // from an uncommon trap in JVMCI compiled code to the uncommon trap handler.
1060
1061 // Communicates the DeoptReason and DeoptAction of the uncommon trap
1062 int _pending_deoptimization;
1063
1064 // Specifies whether the uncommon trap is to bci 0 of a synchronized method
1065 // before the monitor has been acquired.
1066 bool _pending_monitorenter;
1067
1068 // Specifies if the DeoptReason for the last uncommon trap was Reason_transfer_to_interpreter
1069 bool _pending_transfer_to_interpreter;
1070
1071 // Guard for re-entrant call to JVMCIRuntime::adjust_comp_level
1072 bool _adjusting_comp_level;
1073
1074 // An id of a speculation that JVMCI compiled code can use to further describe and
1075 // uniquely identify the speculative optimization guarded by the uncommon trap
1076 long _pending_failed_speculation;
1077
1078 // These fields are mutually exclusive in terms of live ranges.
1079 union {
1080 // Communicates the pc at which the most recent implicit exception occurred
1081 // from the signal handler to a deoptimization stub.
1082 address _implicit_exception_pc;
1083
1084 // Communicates an alternative call target to an i2c stub from a JavaCall .
1085 address _alternate_call_target;
1086 } _jvmci;
1087
1088 // Support for high precision, thread sensitive counters in JVMCI compiled code.
1089 jlong* _jvmci_counters;
1090
1091 public:
1092 static jlong* _jvmci_old_thread_counters;
1093 static void collect_counters(typeArrayOop array);
1094 private:
1095 #endif // INCLUDE_JVMCI
1096
1097 StackGuardState _stack_guard_state;
1098
1099 // Precompute the limit of the stack as used in stack overflow checks.
1100 // We load it from here to simplify the stack overflow check in assembly.
1101 address _stack_overflow_limit;
1102 address _reserved_stack_activation;
1103
1104 // Compiler exception handling (NOTE: The _exception_oop is *NOT* the same as _pending_exception. It is
1105 // used to temp. parsing values into and out of the runtime system during exception handling for compiled
1106 // code)
1107 volatile oop _exception_oop; // Exception thrown in compiled code
1108 volatile address _exception_pc; // PC where exception happened
1109 volatile address _exception_handler_pc; // PC for handler of exception
1110 volatile int _is_method_handle_return; // true (== 1) if the current exception PC is a MethodHandle call site.
1111
1112 private:
1113 // support for JNI critical regions
1114 jint _jni_active_critical; // count of entries into JNI critical region
1115
1116 // Checked JNI: function name requires exception check
1117 char* _pending_jni_exception_check_fn;
1118
1119 // For deadlock detection.
1120 int _depth_first_number;
1121
1122 // JVMTI PopFrame support
1123 // This is set to popframe_pending to signal that top Java frame should be popped immediately
1124 int _popframe_condition;
1125
1126 // If reallocation of scalar replaced objects fails, we throw OOM
1127 // and during exception propagation, pop the top
1128 // _frames_to_pop_failed_realloc frames, the ones that reference
1129 // failed reallocations.
1130 int _frames_to_pop_failed_realloc;
1131
1132 // Buffered value types support
1133 void* _vt_alloc_ptr;
1134 void* _vt_alloc_limit;
1135 VTBufferChunk* _local_free_chunk;
1136 VTBuffer::Mark _current_vtbuffer_mark;
1137 // Next 4 fields are used to monitor VT buffer memory consumption
1138 // We may want to not support them in PRODUCT builds
1139 jint _vtchunk_in_use;
1140 jint _vtchunk_max;
1141 jint _vtchunk_total_returned;
1142 jint _vtchunk_total_failed;
1143 jlong _vtchunk_total_memory_buffered;
1144
1145 #ifndef PRODUCT
1146 int _jmp_ring_index;
1147 struct {
1148 // We use intptr_t instead of address so debugger doesn't try and display strings
1149 intptr_t _target;
1150 intptr_t _instruction;
1151 const char* _file;
1152 int _line;
1153 } _jmp_ring[jump_ring_buffer_size];
1154 #endif // PRODUCT
1155
1156 friend class VMThread;
1157 friend class ThreadWaitTransition;
1158 friend class VM_Exit;
1159
1160 void initialize(); // Initialized the instance variables
1161
1162 public:
1163 // Constructor
1164 JavaThread(bool is_attaching_via_jni = false); // for main thread and JNI attached threads
1165 JavaThread(ThreadFunction entry_point, size_t stack_size = 0);
1166 ~JavaThread();
1167
1168 #ifdef ASSERT
1169 // verify this JavaThread hasn't be published in the Threads::list yet
1170 void verify_not_published();
1171 #endif
1172
1173 //JNI functiontable getter/setter for JVMTI jni function table interception API.
1174 void set_jni_functions(struct JNINativeInterface_* functionTable) {
1175 _jni_environment.functions = functionTable;
1176 }
1177 struct JNINativeInterface_* get_jni_functions() {
1178 return (struct JNINativeInterface_ *)_jni_environment.functions;
1179 }
1180
1181 // This function is called at thread creation to allow
1182 // platform specific thread variables to be initialized.
1183 void cache_global_variables();
1184
1185 // Executes Shutdown.shutdown()
1186 void invoke_shutdown_hooks();
1187
1188 // Cleanup on thread exit
1189 enum ExitType {
1190 normal_exit,
1191 jni_detach
1192 };
1193 void exit(bool destroy_vm, ExitType exit_type = normal_exit);
1194
1195 void cleanup_failed_attach_current_thread();
1196
1197 // Testers
1198 virtual bool is_Java_thread() const { return true; }
1199 virtual bool can_call_java() const { return true; }
1200
1201 // Thread chain operations
1202 JavaThread* next() const { return _next; }
1203 void set_next(JavaThread* p) { _next = p; }
1204
1205 // Thread oop. threadObj() can be NULL for initial JavaThread
1206 // (or for threads attached via JNI)
1207 oop threadObj() const { return _threadObj; }
1208 void set_threadObj(oop p) { _threadObj = p; }
1209
1210 ThreadPriority java_priority() const; // Read from threadObj()
1211
1212 // Prepare thread and add to priority queue. If a priority is
1213 // not specified, use the priority of the thread object. Threads_lock
1214 // must be held while this function is called.
1215 void prepare(jobject jni_thread, ThreadPriority prio=NoPriority);
1216
1217 void set_saved_exception_pc(address pc) { _saved_exception_pc = pc; }
1218 address saved_exception_pc() { return _saved_exception_pc; }
1219
1220
1221 ThreadFunction entry_point() const { return _entry_point; }
1222
1223 // Allocates a new Java level thread object for this thread. thread_name may be NULL.
1224 void allocate_threadObj(Handle thread_group, const char* thread_name, bool daemon, TRAPS);
1225
1226 // Last frame anchor routines
1227
1228 JavaFrameAnchor* frame_anchor(void) { return &_anchor; }
1229
1230 // last_Java_sp
1231 bool has_last_Java_frame() const { return _anchor.has_last_Java_frame(); }
1232 intptr_t* last_Java_sp() const { return _anchor.last_Java_sp(); }
1233
1234 // last_Java_pc
1235
1236 address last_Java_pc(void) { return _anchor.last_Java_pc(); }
1237
1238 // Safepoint support
1239 #if !(defined(PPC64) || defined(AARCH64))
1240 JavaThreadState thread_state() const { return _thread_state; }
1241 void set_thread_state(JavaThreadState s) { _thread_state = s; }
1242 #else
1243 // Use membars when accessing volatile _thread_state. See
1244 // Threads::create_vm() for size checks.
1245 inline JavaThreadState thread_state() const;
1246 inline void set_thread_state(JavaThreadState s);
1247 #endif
1248 ThreadSafepointState *safepoint_state() const { return _safepoint_state; }
1249 void set_safepoint_state(ThreadSafepointState *state) { _safepoint_state = state; }
1250 bool is_at_poll_safepoint() { return _safepoint_state->is_at_poll_safepoint(); }
1251
1252 // JavaThread termination and lifecycle support:
1253 void smr_delete();
1254 bool on_thread_list() const { return _on_thread_list; }
1255 void set_on_thread_list() { _on_thread_list = true; }
1256
1257 // thread has called JavaThread::exit() or is terminated
1258 bool is_exiting() const;
1259 // thread is terminated (no longer on the threads list); we compare
1260 // against the two non-terminated values so that a freed JavaThread
1261 // will also be considered terminated.
1262 bool check_is_terminated(TerminatedTypes l_terminated) const {
1263 return l_terminated != _not_terminated && l_terminated != _thread_exiting;
1264 }
1265 bool is_terminated() const;
1266 void set_terminated(TerminatedTypes t);
1267 // special for Threads::remove() which is static:
1268 void set_terminated_value();
1269 void block_if_vm_exited();
1270
1271 bool doing_unsafe_access() { return _doing_unsafe_access; }
1272 void set_doing_unsafe_access(bool val) { _doing_unsafe_access = val; }
1273
1274 bool do_not_unlock_if_synchronized() { return _do_not_unlock_if_synchronized; }
1275 void set_do_not_unlock_if_synchronized(bool val) { _do_not_unlock_if_synchronized = val; }
1276
1277 inline void set_polling_page_release(void* poll_value);
1278 inline void set_polling_page(void* poll_value);
1279 inline volatile void* get_polling_page();
1280
1281 private:
1282 // Support for thread handshake operations
1283 HandshakeState _handshake;
1284 public:
1285 void set_handshake_operation(HandshakeOperation* op) {
1286 _handshake.set_operation(this, op);
1287 }
1288
1289 bool has_handshake() const {
1290 return _handshake.has_operation();
1291 }
1292
1293 void cancel_handshake() {
1294 _handshake.cancel(this);
1295 }
1296
1297 void handshake_process_by_self() {
1298 _handshake.process_by_self(this);
1299 }
1300
1301 void handshake_process_by_vmthread() {
1302 _handshake.process_by_vmthread(this);
1303 }
1304
1305 // Suspend/resume support for JavaThread
1306 private:
1307 inline void set_ext_suspended();
1308 inline void clear_ext_suspended();
1309
1310 public:
1311 void java_suspend();
1312 void java_resume();
1313 int java_suspend_self();
1314
1315 void check_and_wait_while_suspended() {
1316 assert(JavaThread::current() == this, "sanity check");
1317
1318 bool do_self_suspend;
1319 do {
1320 // were we externally suspended while we were waiting?
1321 do_self_suspend = handle_special_suspend_equivalent_condition();
1322 if (do_self_suspend) {
1323 // don't surprise the thread that suspended us by returning
1324 java_suspend_self();
1325 set_suspend_equivalent();
1326 }
1327 } while (do_self_suspend);
1328 }
1329 static void check_safepoint_and_suspend_for_native_trans(JavaThread *thread);
1330 // Check for async exception in addition to safepoint and suspend request.
1331 static void check_special_condition_for_native_trans(JavaThread *thread);
1332
1333 // Same as check_special_condition_for_native_trans but finishes the
1334 // transition into thread_in_Java mode so that it can potentially
1335 // block.
1336 static void check_special_condition_for_native_trans_and_transition(JavaThread *thread);
1337
1338 bool is_ext_suspend_completed(bool called_by_wait, int delay, uint32_t *bits);
1339 bool is_ext_suspend_completed_with_lock(uint32_t *bits) {
1340 MutexLockerEx ml(SR_lock(), Mutex::_no_safepoint_check_flag);
1341 // Warning: is_ext_suspend_completed() may temporarily drop the
1342 // SR_lock to allow the thread to reach a stable thread state if
1343 // it is currently in a transient thread state.
1344 return is_ext_suspend_completed(false /* !called_by_wait */,
1345 SuspendRetryDelay, bits);
1346 }
1347
1348 // We cannot allow wait_for_ext_suspend_completion() to run forever or
1349 // we could hang. SuspendRetryCount and SuspendRetryDelay are normally
1350 // passed as the count and delay parameters. Experiments with specific
1351 // calls to wait_for_ext_suspend_completion() can be done by passing
1352 // other values in the code. Experiments with all calls can be done
1353 // via the appropriate -XX options.
1354 bool wait_for_ext_suspend_completion(int count, int delay, uint32_t *bits);
1355
1356 // test for suspend - most (all?) of these should go away
1357 bool is_thread_fully_suspended(bool wait_for_suspend, uint32_t *bits);
1358
1359 inline void set_external_suspend();
1360 inline void clear_external_suspend();
1361
1362 inline void set_deopt_suspend();
1363 inline void clear_deopt_suspend();
1364 bool is_deopt_suspend() { return (_suspend_flags & _deopt_suspend) != 0; }
1365
1366 bool is_external_suspend() const {
1367 return (_suspend_flags & _external_suspend) != 0;
1368 }
1369 // Whenever a thread transitions from native to vm/java it must suspend
1370 // if external|deopt suspend is present.
1371 bool is_suspend_after_native() const {
1372 return (_suspend_flags & (_external_suspend | _deopt_suspend)) != 0;
1373 }
1374
1375 // external suspend request is completed
1376 bool is_ext_suspended() const {
1377 return (_suspend_flags & _ext_suspended) != 0;
1378 }
1379
1380 bool is_external_suspend_with_lock() const {
1381 MutexLockerEx ml(SR_lock(), Mutex::_no_safepoint_check_flag);
1382 return is_external_suspend();
1383 }
1384
1385 // Special method to handle a pending external suspend request
1386 // when a suspend equivalent condition lifts.
1387 bool handle_special_suspend_equivalent_condition() {
1388 assert(is_suspend_equivalent(),
1389 "should only be called in a suspend equivalence condition");
1390 MutexLockerEx ml(SR_lock(), Mutex::_no_safepoint_check_flag);
1391 bool ret = is_external_suspend();
1392 if (!ret) {
1393 // not about to self-suspend so clear suspend equivalence
1394 clear_suspend_equivalent();
1395 }
1396 // implied else:
1397 // We have a pending external suspend request so we leave the
1398 // suspend_equivalent flag set until java_suspend_self() sets
1399 // the ext_suspended flag and clears the suspend_equivalent
1400 // flag. This insures that wait_for_ext_suspend_completion()
1401 // will return consistent values.
1402 return ret;
1403 }
1404
1405 // utility methods to see if we are doing some kind of suspension
1406 bool is_being_ext_suspended() const {
1407 MutexLockerEx ml(SR_lock(), Mutex::_no_safepoint_check_flag);
1408 return is_ext_suspended() || is_external_suspend();
1409 }
1410
1411 bool is_suspend_equivalent() const { return _suspend_equivalent; }
1412
1413 void set_suspend_equivalent() { _suspend_equivalent = true; }
1414 void clear_suspend_equivalent() { _suspend_equivalent = false; }
1415
1416 // Thread.stop support
1417 void send_thread_stop(oop throwable);
1418 AsyncRequests clear_special_runtime_exit_condition() {
1419 AsyncRequests x = _special_runtime_exit_condition;
1420 _special_runtime_exit_condition = _no_async_condition;
1421 return x;
1422 }
1423
1424 // Are any async conditions present?
1425 bool has_async_condition() { return (_special_runtime_exit_condition != _no_async_condition); }
1426
1427 void check_and_handle_async_exceptions(bool check_unsafe_error = true);
1428
1429 // these next two are also used for self-suspension and async exception support
1430 void handle_special_runtime_exit_condition(bool check_asyncs = true);
1431
1432 // Return true if JavaThread has an asynchronous condition or
1433 // if external suspension is requested.
1434 bool has_special_runtime_exit_condition() {
1435 // Because we don't use is_external_suspend_with_lock
1436 // it is possible that we won't see an asynchronous external suspend
1437 // request that has just gotten started, i.e., SR_lock grabbed but
1438 // _external_suspend field change either not made yet or not visible
1439 // yet. However, this is okay because the request is asynchronous and
1440 // we will see the new flag value the next time through. It's also
1441 // possible that the external suspend request is dropped after
1442 // we have checked is_external_suspend(), we will recheck its value
1443 // under SR_lock in java_suspend_self().
1444 return (_special_runtime_exit_condition != _no_async_condition) ||
1445 is_external_suspend() || is_trace_suspend();
1446 }
1447
1448 void set_pending_unsafe_access_error() { _special_runtime_exit_condition = _async_unsafe_access_error; }
1449
1450 inline void set_pending_async_exception(oop e);
1451
1452 // Fast-locking support
1453 bool is_lock_owned(address adr) const;
1454
1455 // Accessors for vframe array top
1456 // The linked list of vframe arrays are sorted on sp. This means when we
1457 // unpack the head must contain the vframe array to unpack.
1458 void set_vframe_array_head(vframeArray* value) { _vframe_array_head = value; }
1459 vframeArray* vframe_array_head() const { return _vframe_array_head; }
1460
1461 // Side structure for deferring update of java frame locals until deopt occurs
1462 GrowableArray<jvmtiDeferredLocalVariableSet*>* deferred_locals() const { return _deferred_locals_updates; }
1463 void set_deferred_locals(GrowableArray<jvmtiDeferredLocalVariableSet *>* vf) { _deferred_locals_updates = vf; }
1464
1465 // These only really exist to make debugging deopt problems simpler
1466
1467 void set_vframe_array_last(vframeArray* value) { _vframe_array_last = value; }
1468 vframeArray* vframe_array_last() const { return _vframe_array_last; }
1469
1470 // The special resourceMark used during deoptimization
1471
1472 void set_deopt_mark(DeoptResourceMark* value) { _deopt_mark = value; }
1473 DeoptResourceMark* deopt_mark(void) { return _deopt_mark; }
1474
1475 intptr_t* must_deopt_id() { return _must_deopt_id; }
1476 void set_must_deopt_id(intptr_t* id) { _must_deopt_id = id; }
1477 void clear_must_deopt_id() { _must_deopt_id = NULL; }
1478
1479 void set_deopt_compiled_method(CompiledMethod* nm) { _deopt_nmethod = nm; }
1480 CompiledMethod* deopt_compiled_method() { return _deopt_nmethod; }
1481
1482 Method* callee_target() const { return _callee_target; }
1483 void set_callee_target (Method* x) { _callee_target = x; }
1484
1485 // Oop results of vm runtime calls
1486 oop vm_result() const { return _vm_result; }
1487 void set_vm_result (oop x) { _vm_result = x; }
1488
1489 Metadata* vm_result_2() const { return _vm_result_2; }
1490 void set_vm_result_2 (Metadata* x) { _vm_result_2 = x; }
1491
1492 oop return_buffered_value() const { return _return_buffered_value; }
1493 void set_return_buffered_value(oop val) { _return_buffered_value = val; }
1494
1495 MemRegion deferred_card_mark() const { return _deferred_card_mark; }
1496 void set_deferred_card_mark(MemRegion mr) { _deferred_card_mark = mr; }
1497
1498 #if INCLUDE_JVMCI
1499 int pending_deoptimization() const { return _pending_deoptimization; }
1500 long pending_failed_speculation() const { return _pending_failed_speculation; }
1501 bool adjusting_comp_level() const { return _adjusting_comp_level; }
1502 void set_adjusting_comp_level(bool b) { _adjusting_comp_level = b; }
1503 bool has_pending_monitorenter() const { return _pending_monitorenter; }
1504 void set_pending_monitorenter(bool b) { _pending_monitorenter = b; }
1505 void set_pending_deoptimization(int reason) { _pending_deoptimization = reason; }
1506 void set_pending_failed_speculation(long failed_speculation) { _pending_failed_speculation = failed_speculation; }
1507 void set_pending_transfer_to_interpreter(bool b) { _pending_transfer_to_interpreter = b; }
1508 void set_jvmci_alternate_call_target(address a) { assert(_jvmci._alternate_call_target == NULL, "must be"); _jvmci._alternate_call_target = a; }
1509 void set_jvmci_implicit_exception_pc(address a) { assert(_jvmci._implicit_exception_pc == NULL, "must be"); _jvmci._implicit_exception_pc = a; }
1510 #endif // INCLUDE_JVMCI
1511
1512 // Exception handling for compiled methods
1513 oop exception_oop() const { return _exception_oop; }
1514 address exception_pc() const { return _exception_pc; }
1515 address exception_handler_pc() const { return _exception_handler_pc; }
1516 bool is_method_handle_return() const { return _is_method_handle_return == 1; }
1517
1518 void set_exception_oop(oop o) { (void)const_cast<oop&>(_exception_oop = o); }
1519 void set_exception_pc(address a) { _exception_pc = a; }
1520 void set_exception_handler_pc(address a) { _exception_handler_pc = a; }
1521 void set_is_method_handle_return(bool value) { _is_method_handle_return = value ? 1 : 0; }
1522
1523 void clear_exception_oop_and_pc() {
1524 set_exception_oop(NULL);
1525 set_exception_pc(NULL);
1526 }
1527
1528 // Stack overflow support
1529 //
1530 // (small addresses)
1531 //
1532 // -- <-- stack_end() ---
1533 // | |
1534 // | red pages |
1535 // | |
1536 // -- <-- stack_red_zone_base() |
1537 // | |
1538 // | guard
1539 // | yellow pages zone
1540 // | |
1541 // | |
1542 // -- <-- stack_yellow_zone_base() |
1543 // | |
1544 // | |
1545 // | reserved pages |
1546 // | |
1547 // -- <-- stack_reserved_zone_base() --- ---
1548 // /|\ shadow <-- stack_overflow_limit() (somewhere in here)
1549 // | zone
1550 // \|/ size
1551 // some untouched memory ---
1552 //
1553 //
1554 // --
1555 // |
1556 // | shadow zone
1557 // |
1558 // --
1559 // x frame n
1560 // --
1561 // x frame n-1
1562 // x
1563 // --
1564 // ...
1565 //
1566 // --
1567 // x frame 0
1568 // -- <-- stack_base()
1569 //
1570 // (large addresses)
1571 //
1572
1573 private:
1574 // These values are derived from flags StackRedPages, StackYellowPages,
1575 // StackReservedPages and StackShadowPages. The zone size is determined
1576 // ergonomically if page_size > 4K.
1577 static size_t _stack_red_zone_size;
1578 static size_t _stack_yellow_zone_size;
1579 static size_t _stack_reserved_zone_size;
1580 static size_t _stack_shadow_zone_size;
1581 public:
1582 inline size_t stack_available(address cur_sp);
1583
1584 static size_t stack_red_zone_size() {
1585 assert(_stack_red_zone_size > 0, "Don't call this before the field is initialized.");
1586 return _stack_red_zone_size;
1587 }
1588 static void set_stack_red_zone_size(size_t s) {
1589 assert(is_aligned(s, os::vm_page_size()),
1590 "We can not protect if the red zone size is not page aligned.");
1591 assert(_stack_red_zone_size == 0, "This should be called only once.");
1592 _stack_red_zone_size = s;
1593 }
1594 address stack_red_zone_base() {
1595 return (address)(stack_end() + stack_red_zone_size());
1596 }
1597 bool in_stack_red_zone(address a) {
1598 return a <= stack_red_zone_base() && a >= stack_end();
1599 }
1600
1601 static size_t stack_yellow_zone_size() {
1602 assert(_stack_yellow_zone_size > 0, "Don't call this before the field is initialized.");
1603 return _stack_yellow_zone_size;
1604 }
1605 static void set_stack_yellow_zone_size(size_t s) {
1606 assert(is_aligned(s, os::vm_page_size()),
1607 "We can not protect if the yellow zone size is not page aligned.");
1608 assert(_stack_yellow_zone_size == 0, "This should be called only once.");
1609 _stack_yellow_zone_size = s;
1610 }
1611
1612 static size_t stack_reserved_zone_size() {
1613 // _stack_reserved_zone_size may be 0. This indicates the feature is off.
1614 return _stack_reserved_zone_size;
1615 }
1616 static void set_stack_reserved_zone_size(size_t s) {
1617 assert(is_aligned(s, os::vm_page_size()),
1618 "We can not protect if the reserved zone size is not page aligned.");
1619 assert(_stack_reserved_zone_size == 0, "This should be called only once.");
1620 _stack_reserved_zone_size = s;
1621 }
1622 address stack_reserved_zone_base() {
1623 return (address)(stack_end() +
1624 (stack_red_zone_size() + stack_yellow_zone_size() + stack_reserved_zone_size()));
1625 }
1626 bool in_stack_reserved_zone(address a) {
1627 return (a <= stack_reserved_zone_base()) &&
1628 (a >= (address)((intptr_t)stack_reserved_zone_base() - stack_reserved_zone_size()));
1629 }
1630
1631 static size_t stack_yellow_reserved_zone_size() {
1632 return _stack_yellow_zone_size + _stack_reserved_zone_size;
1633 }
1634 bool in_stack_yellow_reserved_zone(address a) {
1635 return (a <= stack_reserved_zone_base()) && (a >= stack_red_zone_base());
1636 }
1637
1638 // Size of red + yellow + reserved zones.
1639 static size_t stack_guard_zone_size() {
1640 return stack_red_zone_size() + stack_yellow_reserved_zone_size();
1641 }
1642
1643 static size_t stack_shadow_zone_size() {
1644 assert(_stack_shadow_zone_size > 0, "Don't call this before the field is initialized.");
1645 return _stack_shadow_zone_size;
1646 }
1647 static void set_stack_shadow_zone_size(size_t s) {
1648 // The shadow area is not allocated or protected, so
1649 // it needs not be page aligned.
1650 // But the stack bang currently assumes that it is a
1651 // multiple of page size. This guarantees that the bang
1652 // loop touches all pages in the shadow zone.
1653 // This can be guaranteed differently, as well. E.g., if
1654 // the page size is a multiple of 4K, banging in 4K steps
1655 // suffices to touch all pages. (Some pages are banged
1656 // several times, though.)
1657 assert(is_aligned(s, os::vm_page_size()),
1658 "Stack bang assumes multiple of page size.");
1659 assert(_stack_shadow_zone_size == 0, "This should be called only once.");
1660 _stack_shadow_zone_size = s;
1661 }
1662
1663 void create_stack_guard_pages();
1664 void remove_stack_guard_pages();
1665
1666 void enable_stack_reserved_zone();
1667 void disable_stack_reserved_zone();
1668 void enable_stack_yellow_reserved_zone();
1669 void disable_stack_yellow_reserved_zone();
1670 void enable_stack_red_zone();
1671 void disable_stack_red_zone();
1672
1673 inline bool stack_guard_zone_unused();
1674 inline bool stack_yellow_reserved_zone_disabled();
1675 inline bool stack_reserved_zone_disabled();
1676 inline bool stack_guards_enabled();
1677
1678 address reserved_stack_activation() const { return _reserved_stack_activation; }
1679 void set_reserved_stack_activation(address addr) {
1680 assert(_reserved_stack_activation == stack_base()
1681 || _reserved_stack_activation == NULL
1682 || addr == stack_base(), "Must not be set twice");
1683 _reserved_stack_activation = addr;
1684 }
1685
1686 // Attempt to reguard the stack after a stack overflow may have occurred.
1687 // Returns true if (a) guard pages are not needed on this thread, (b) the
1688 // pages are already guarded, or (c) the pages were successfully reguarded.
1689 // Returns false if there is not enough stack space to reguard the pages, in
1690 // which case the caller should unwind a frame and try again. The argument
1691 // should be the caller's (approximate) sp.
1692 bool reguard_stack(address cur_sp);
1693 // Similar to above but see if current stackpoint is out of the guard area
1694 // and reguard if possible.
1695 bool reguard_stack(void);
1696
1697 address stack_overflow_limit() { return _stack_overflow_limit; }
1698 void set_stack_overflow_limit() {
1699 _stack_overflow_limit =
1700 stack_end() + MAX2(JavaThread::stack_guard_zone_size(), JavaThread::stack_shadow_zone_size());
1701 }
1702
1703 // Misc. accessors/mutators
1704 void set_do_not_unlock(void) { _do_not_unlock_if_synchronized = true; }
1705 void clr_do_not_unlock(void) { _do_not_unlock_if_synchronized = false; }
1706 bool do_not_unlock(void) { return _do_not_unlock_if_synchronized; }
1707
1708 #ifndef PRODUCT
1709 void record_jump(address target, address instr, const char* file, int line);
1710 #endif // PRODUCT
1711
1712 // For assembly stub generation
1713 static ByteSize threadObj_offset() { return byte_offset_of(JavaThread, _threadObj); }
1714 #ifndef PRODUCT
1715 static ByteSize jmp_ring_index_offset() { return byte_offset_of(JavaThread, _jmp_ring_index); }
1716 static ByteSize jmp_ring_offset() { return byte_offset_of(JavaThread, _jmp_ring); }
1717 #endif // PRODUCT
1718 static ByteSize jni_environment_offset() { return byte_offset_of(JavaThread, _jni_environment); }
1719 static ByteSize pending_jni_exception_check_fn_offset() {
1720 return byte_offset_of(JavaThread, _pending_jni_exception_check_fn);
1721 }
1722 static ByteSize last_Java_sp_offset() {
1723 return byte_offset_of(JavaThread, _anchor) + JavaFrameAnchor::last_Java_sp_offset();
1724 }
1725 static ByteSize last_Java_pc_offset() {
1726 return byte_offset_of(JavaThread, _anchor) + JavaFrameAnchor::last_Java_pc_offset();
1727 }
1728 static ByteSize frame_anchor_offset() {
1729 return byte_offset_of(JavaThread, _anchor);
1730 }
1731 static ByteSize callee_target_offset() { return byte_offset_of(JavaThread, _callee_target); }
1732 static ByteSize vm_result_offset() { return byte_offset_of(JavaThread, _vm_result); }
1733 static ByteSize vm_result_2_offset() { return byte_offset_of(JavaThread, _vm_result_2); }
1734 static ByteSize return_buffered_value_offset() { return byte_offset_of(JavaThread, _return_buffered_value); }
1735 static ByteSize thread_state_offset() { return byte_offset_of(JavaThread, _thread_state); }
1736 static ByteSize saved_exception_pc_offset() { return byte_offset_of(JavaThread, _saved_exception_pc); }
1737 static ByteSize osthread_offset() { return byte_offset_of(JavaThread, _osthread); }
1738 #if INCLUDE_JVMCI
1739 static ByteSize pending_deoptimization_offset() { return byte_offset_of(JavaThread, _pending_deoptimization); }
1740 static ByteSize pending_monitorenter_offset() { return byte_offset_of(JavaThread, _pending_monitorenter); }
1741 static ByteSize pending_failed_speculation_offset() { return byte_offset_of(JavaThread, _pending_failed_speculation); }
1742 static ByteSize jvmci_alternate_call_target_offset() { return byte_offset_of(JavaThread, _jvmci._alternate_call_target); }
1743 static ByteSize jvmci_implicit_exception_pc_offset() { return byte_offset_of(JavaThread, _jvmci._implicit_exception_pc); }
1744 static ByteSize jvmci_counters_offset() { return byte_offset_of(JavaThread, _jvmci_counters); }
1745 #endif // INCLUDE_JVMCI
1746 static ByteSize exception_oop_offset() { return byte_offset_of(JavaThread, _exception_oop); }
1747 static ByteSize exception_pc_offset() { return byte_offset_of(JavaThread, _exception_pc); }
1748 static ByteSize exception_handler_pc_offset() { return byte_offset_of(JavaThread, _exception_handler_pc); }
1749 static ByteSize stack_overflow_limit_offset() { return byte_offset_of(JavaThread, _stack_overflow_limit); }
1750 static ByteSize is_method_handle_return_offset() { return byte_offset_of(JavaThread, _is_method_handle_return); }
1751 static ByteSize stack_guard_state_offset() { return byte_offset_of(JavaThread, _stack_guard_state); }
1752 static ByteSize reserved_stack_activation_offset() { return byte_offset_of(JavaThread, _reserved_stack_activation); }
1753 static ByteSize suspend_flags_offset() { return byte_offset_of(JavaThread, _suspend_flags); }
1754
1755 static ByteSize do_not_unlock_if_synchronized_offset() { return byte_offset_of(JavaThread, _do_not_unlock_if_synchronized); }
1756 static ByteSize should_post_on_exceptions_flag_offset() {
1757 return byte_offset_of(JavaThread, _should_post_on_exceptions_flag);
1758 }
1759
1760 // Returns the jni environment for this thread
1761 JNIEnv* jni_environment() { return &_jni_environment; }
1762
1763 static JavaThread* thread_from_jni_environment(JNIEnv* env) {
1764 JavaThread *thread_from_jni_env = (JavaThread*)((intptr_t)env - in_bytes(jni_environment_offset()));
1765 // Only return NULL if thread is off the thread list; starting to
1766 // exit should not return NULL.
1767 if (thread_from_jni_env->is_terminated()) {
1768 thread_from_jni_env->block_if_vm_exited();
1769 return NULL;
1770 } else {
1771 return thread_from_jni_env;
1772 }
1773 }
1774
1775 // JNI critical regions. These can nest.
1776 bool in_critical() { return _jni_active_critical > 0; }
1777 bool in_last_critical() { return _jni_active_critical == 1; }
1778 void enter_critical() {
1779 assert(Thread::current() == this ||
1780 (Thread::current()->is_VM_thread() &&
1781 SafepointSynchronize::is_synchronizing()),
1782 "this must be current thread or synchronizing");
1783 _jni_active_critical++;
1784 }
1785 void exit_critical() {
1786 assert(Thread::current() == this, "this must be current thread");
1787 _jni_active_critical--;
1788 assert(_jni_active_critical >= 0, "JNI critical nesting problem?");
1789 }
1790
1791 // Checked JNI: is the programmer required to check for exceptions, if so specify
1792 // which function name. Returning to a Java frame should implicitly clear the
1793 // pending check, this is done for Native->Java transitions (i.e. user JNI code).
1794 // VM->Java transistions are not cleared, it is expected that JNI code enclosed
1795 // within ThreadToNativeFromVM makes proper exception checks (i.e. VM internal).
1796 bool is_pending_jni_exception_check() const { return _pending_jni_exception_check_fn != NULL; }
1797 void clear_pending_jni_exception_check() { _pending_jni_exception_check_fn = NULL; }
1798 const char* get_pending_jni_exception_check() const { return _pending_jni_exception_check_fn; }
1799 void set_pending_jni_exception_check(const char* fn_name) { _pending_jni_exception_check_fn = (char*) fn_name; }
1800
1801 // For deadlock detection
1802 int depth_first_number() { return _depth_first_number; }
1803 void set_depth_first_number(int dfn) { _depth_first_number = dfn; }
1804
1805 private:
1806 void set_monitor_chunks(MonitorChunk* monitor_chunks) { _monitor_chunks = monitor_chunks; }
1807
1808 public:
1809 MonitorChunk* monitor_chunks() const { return _monitor_chunks; }
1810 void add_monitor_chunk(MonitorChunk* chunk);
1811 void remove_monitor_chunk(MonitorChunk* chunk);
1812 bool in_deopt_handler() const { return _in_deopt_handler > 0; }
1813 void inc_in_deopt_handler() { _in_deopt_handler++; }
1814 void dec_in_deopt_handler() {
1815 assert(_in_deopt_handler > 0, "mismatched deopt nesting");
1816 if (_in_deopt_handler > 0) { // robustness
1817 _in_deopt_handler--;
1818 }
1819 }
1820
1821 private:
1822 void set_entry_point(ThreadFunction entry_point) { _entry_point = entry_point; }
1823
1824 public:
1825
1826 // Frame iteration; calls the function f for all frames on the stack
1827 void frames_do(void f(frame*, const RegisterMap*));
1828
1829 // Memory operations
1830 void oops_do(OopClosure* f, CodeBlobClosure* cf);
1831
1832 // Sweeper operations
1833 virtual void nmethods_do(CodeBlobClosure* cf);
1834
1835 // RedefineClasses Support
1836 void metadata_do(void f(Metadata*));
1837
1838 // Misc. operations
1839 char* name() const { return (char*)get_thread_name(); }
1840 void print_on(outputStream* st, bool print_extended_info) const;
1841 void print_on(outputStream* st) const { print_on(st, false); }
1842 void print_value();
1843 void print_thread_state_on(outputStream*) const PRODUCT_RETURN;
1844 void print_thread_state() const PRODUCT_RETURN;
1845 void print_on_error(outputStream* st, char* buf, int buflen) const;
1846 void print_name_on_error(outputStream* st, char* buf, int buflen) const;
1847 void print_vt_buffer_stats_on(outputStream* st) const;
1848 void verify();
1849 const char* get_thread_name() const;
1850 private:
1851 // factor out low-level mechanics for use in both normal and error cases
1852 const char* get_thread_name_string(char* buf = NULL, int buflen = 0) const;
1853 public:
1854 const char* get_threadgroup_name() const;
1855 const char* get_parent_name() const;
1856
1857 // Accessing frames
1858 frame last_frame() {
1859 _anchor.make_walkable(this);
1860 return pd_last_frame();
1861 }
1862 javaVFrame* last_java_vframe(RegisterMap* reg_map);
1863
1864 // Returns method at 'depth' java or native frames down the stack
1865 // Used for security checks
1866 Klass* security_get_caller_class(int depth);
1867
1868 // Print stack trace in external format
1869 void print_stack_on(outputStream* st);
1870 void print_stack() { print_stack_on(tty); }
1871
1872 // Print stack traces in various internal formats
1873 void trace_stack() PRODUCT_RETURN;
1874 void trace_stack_from(vframe* start_vf) PRODUCT_RETURN;
1875 void trace_frames() PRODUCT_RETURN;
1876 void trace_oops() PRODUCT_RETURN;
1877
1878 // Print an annotated view of the stack frames
1879 void print_frame_layout(int depth = 0, bool validate_only = false) NOT_DEBUG_RETURN;
1880 void validate_frame_layout() {
1881 print_frame_layout(0, true);
1882 }
1883
1884 // Returns the number of stack frames on the stack
1885 int depth() const;
1886
1887 // Function for testing deoptimization
1888 void deoptimize();
1889 void make_zombies();
1890
1891 void deoptimized_wrt_marked_nmethods();
1892
1893 public:
1894 // Returns the running thread as a JavaThread
1895 static inline JavaThread* current();
1896
1897 // Returns the active Java thread. Do not use this if you know you are calling
1898 // from a JavaThread, as it's slower than JavaThread::current. If called from
1899 // the VMThread, it also returns the JavaThread that instigated the VMThread's
1900 // operation. You may not want that either.
1901 static JavaThread* active();
1902
1903 inline CompilerThread* as_CompilerThread();
1904
1905 public:
1906 virtual void run();
1907 void thread_main_inner();
1908
1909 private:
1910 // PRIVILEGED STACK
1911 PrivilegedElement* _privileged_stack_top;
1912 GrowableArray<oop>* _array_for_gc;
1913 public:
1914
1915 // Returns the privileged_stack information.
1916 PrivilegedElement* privileged_stack_top() const { return _privileged_stack_top; }
1917 void set_privileged_stack_top(PrivilegedElement *e) { _privileged_stack_top = e; }
1918 void register_array_for_gc(GrowableArray<oop>* array) { _array_for_gc = array; }
1919
1920 public:
1921 // Thread local information maintained by JVMTI.
1922 void set_jvmti_thread_state(JvmtiThreadState *value) { _jvmti_thread_state = value; }
1923 // A JvmtiThreadState is lazily allocated. This jvmti_thread_state()
1924 // getter is used to get this JavaThread's JvmtiThreadState if it has
1925 // one which means NULL can be returned. JvmtiThreadState::state_for()
1926 // is used to get the specified JavaThread's JvmtiThreadState if it has
1927 // one or it allocates a new JvmtiThreadState for the JavaThread and
1928 // returns it. JvmtiThreadState::state_for() will return NULL only if
1929 // the specified JavaThread is exiting.
1930 JvmtiThreadState *jvmti_thread_state() const { return _jvmti_thread_state; }
1931 static ByteSize jvmti_thread_state_offset() { return byte_offset_of(JavaThread, _jvmti_thread_state); }
1932
1933 // JVMTI PopFrame support
1934 // Setting and clearing popframe_condition
1935 // All of these enumerated values are bits. popframe_pending
1936 // indicates that a PopFrame() has been requested and not yet been
1937 // completed. popframe_processing indicates that that PopFrame() is in
1938 // the process of being completed. popframe_force_deopt_reexecution_bit
1939 // indicates that special handling is required when returning to a
1940 // deoptimized caller.
1941 enum PopCondition {
1942 popframe_inactive = 0x00,
1943 popframe_pending_bit = 0x01,
1944 popframe_processing_bit = 0x02,
1945 popframe_force_deopt_reexecution_bit = 0x04
1946 };
1947 PopCondition popframe_condition() { return (PopCondition) _popframe_condition; }
1948 void set_popframe_condition(PopCondition c) { _popframe_condition = c; }
1949 void set_popframe_condition_bit(PopCondition c) { _popframe_condition |= c; }
1950 void clear_popframe_condition() { _popframe_condition = popframe_inactive; }
1951 static ByteSize popframe_condition_offset() { return byte_offset_of(JavaThread, _popframe_condition); }
1952 bool has_pending_popframe() { return (popframe_condition() & popframe_pending_bit) != 0; }
1953 bool popframe_forcing_deopt_reexecution() { return (popframe_condition() & popframe_force_deopt_reexecution_bit) != 0; }
1954 void clear_popframe_forcing_deopt_reexecution() { _popframe_condition &= ~popframe_force_deopt_reexecution_bit; }
1955 #ifdef CC_INTERP
1956 bool pop_frame_pending(void) { return ((_popframe_condition & popframe_pending_bit) != 0); }
1957 void clr_pop_frame_pending(void) { _popframe_condition = popframe_inactive; }
1958 bool pop_frame_in_process(void) { return ((_popframe_condition & popframe_processing_bit) != 0); }
1959 void set_pop_frame_in_process(void) { _popframe_condition |= popframe_processing_bit; }
1960 void clr_pop_frame_in_process(void) { _popframe_condition &= ~popframe_processing_bit; }
1961 #endif
1962
1963 int frames_to_pop_failed_realloc() const { return _frames_to_pop_failed_realloc; }
1964 void set_frames_to_pop_failed_realloc(int nb) { _frames_to_pop_failed_realloc = nb; }
1965 void dec_frames_to_pop_failed_realloc() { _frames_to_pop_failed_realloc--; }
1966
1967 private:
1968 // Saved incoming arguments to popped frame.
1969 // Used only when popped interpreted frame returns to deoptimized frame.
1970 void* _popframe_preserved_args;
1971 int _popframe_preserved_args_size;
1972
1973 public:
1974 void popframe_preserve_args(ByteSize size_in_bytes, void* start);
1975 void* popframe_preserved_args();
1976 ByteSize popframe_preserved_args_size();
1977 WordSize popframe_preserved_args_size_in_words();
1978 void popframe_free_preserved_args();
1979
1980
1981 private:
1982 JvmtiThreadState *_jvmti_thread_state;
1983
1984 // Used by the interpreter in fullspeed mode for frame pop, method
1985 // entry, method exit and single stepping support. This field is
1986 // only set to non-zero by the VM_EnterInterpOnlyMode VM operation.
1987 // It can be set to zero asynchronously (i.e., without a VM operation
1988 // or a lock) so we have to be very careful.
1989 int _interp_only_mode;
1990
1991 public:
1992 // used by the interpreter for fullspeed debugging support (see above)
1993 static ByteSize interp_only_mode_offset() { return byte_offset_of(JavaThread, _interp_only_mode); }
1994 bool is_interp_only_mode() { return (_interp_only_mode != 0); }
1995 int get_interp_only_mode() { return _interp_only_mode; }
1996 void increment_interp_only_mode() { ++_interp_only_mode; }
1997 void decrement_interp_only_mode() { --_interp_only_mode; }
1998
1999 // support for cached flag that indicates whether exceptions need to be posted for this thread
2000 // if this is false, we can avoid deoptimizing when events are thrown
2001 // this gets set to reflect whether jvmtiExport::post_exception_throw would actually do anything
2002 private:
2003 int _should_post_on_exceptions_flag;
2004
2005 public:
2006 int should_post_on_exceptions_flag() { return _should_post_on_exceptions_flag; }
2007 void set_should_post_on_exceptions_flag(int val) { _should_post_on_exceptions_flag = val; }
2008
2009 private:
2010 ThreadStatistics *_thread_stat;
2011
2012 public:
2013 ThreadStatistics* get_thread_stat() const { return _thread_stat; }
2014
2015 // Return a blocker object for which this thread is blocked parking.
2016 oop current_park_blocker();
2017
2018 private:
2019 static size_t _stack_size_at_create;
2020
2021 public:
2022 static inline size_t stack_size_at_create(void) {
2023 return _stack_size_at_create;
2024 }
2025 static inline void set_stack_size_at_create(size_t value) {
2026 _stack_size_at_create = value;
2027 }
2028
2029 void* vt_alloc_ptr() const { return _vt_alloc_ptr; }
2030 void set_vt_alloc_ptr(void* ptr) { _vt_alloc_ptr = ptr; }
2031 void* vt_alloc_limit() const { return _vt_alloc_limit; }
2032 void set_vt_alloc_limit(void* ptr) { _vt_alloc_limit = ptr; }
2033 VTBufferChunk* local_free_chunk() const { return _local_free_chunk; }
2034 void set_local_free_chunk(VTBufferChunk* chunk) { _local_free_chunk = chunk; }
2035 VTBufferChunk* current_chunk() {
2036 if (_vt_alloc_ptr == NULL) return NULL;
2037 VTBufferChunk* chunk = VTBufferChunk::chunk(_vt_alloc_ptr);
2038 assert(chunk->owner() == this, "Sanity check");
2039 return chunk;
2040 // return _vt_alloc_ptr == NULL ? NULL : VTBufferChunk::chunk(_vt_alloc_ptr);
2041 }
2042 VTBuffer::Mark current_vtbuffer_mark() const { return _current_vtbuffer_mark; }
2043 void set_current_vtbuffer_mark(VTBuffer::Mark m) { _current_vtbuffer_mark = m ; }
2044
2045 void increment_vtchunk_in_use() {
2046 _vtchunk_in_use++;
2047 if (_vtchunk_in_use > _vtchunk_max) _vtchunk_max = _vtchunk_in_use;
2048 }
2049 void decrement_vtchunk_in_use() { _vtchunk_in_use--; }
2050 jint vtchunk_in_use() const { return _vtchunk_in_use; }
2051 jint vtchunk_max() const { return _vtchunk_max; }
2052 void increment_vtchunk_returned() { _vtchunk_total_returned++; }
2053 jint vtchunk_total_returned() const { return _vtchunk_total_returned; }
2054 void increment_vtchunk_failed() { _vtchunk_total_failed++; }
2055 jint vtchunk_total_failed() const { return _vtchunk_total_failed; }
2056 void increment_vtchunk_total_memory_buffered(jlong size) { _vtchunk_total_memory_buffered += size; }
2057 jlong vtchunk_total_memory_buffered() const { return _vtchunk_total_memory_buffered; }
2058
2059 static ByteSize vt_alloc_ptr_offset() { return byte_offset_of(JavaThread, _vt_alloc_ptr); }
2060
2061
2062 // Machine dependent stuff
2063 #include OS_CPU_HEADER(thread)
2064
2065 public:
2066 void set_blocked_on_compilation(bool value) {
2067 _blocked_on_compilation = value;
2068 }
2069
2070 bool blocked_on_compilation() {
2071 return _blocked_on_compilation;
2072 }
2073 protected:
2074 bool _blocked_on_compilation;
2075
2076
2077 // JSR166 per-thread parker
2078 private:
2079 Parker* _parker;
2080 public:
2081 Parker* parker() { return _parker; }
2082
2083 // Biased locking support
2084 private:
2085 GrowableArray<MonitorInfo*>* _cached_monitor_info;
2086 public:
2087 GrowableArray<MonitorInfo*>* cached_monitor_info() { return _cached_monitor_info; }
2088 void set_cached_monitor_info(GrowableArray<MonitorInfo*>* info) { _cached_monitor_info = info; }
2089
2090 // clearing/querying jni attach status
2091 bool is_attaching_via_jni() const { return _jni_attach_state == _attaching_via_jni; }
2092 bool has_attached_via_jni() const { return is_attaching_via_jni() || _jni_attach_state == _attached_via_jni; }
2093 inline void set_done_attaching_via_jni();
2094 };
2095
2096 // Inline implementation of JavaThread::current
2097 inline JavaThread* JavaThread::current() {
2098 Thread* thread = Thread::current();
2099 assert(thread->is_Java_thread(), "just checking");
2100 return (JavaThread*)thread;
2101 }
2102
2103 inline CompilerThread* JavaThread::as_CompilerThread() {
2104 assert(is_Compiler_thread(), "just checking");
2105 return (CompilerThread*)this;
2106 }
2107
2108 // Dedicated thread to sweep the code cache
2109 class CodeCacheSweeperThread : public JavaThread {
2110 CompiledMethod* _scanned_compiled_method; // nmethod being scanned by the sweeper
2111 public:
2112 CodeCacheSweeperThread();
2113 // Track the nmethod currently being scanned by the sweeper
2114 void set_scanned_compiled_method(CompiledMethod* cm) {
2115 assert(_scanned_compiled_method == NULL || cm == NULL, "should reset to NULL before writing a new value");
2116 _scanned_compiled_method = cm;
2117 }
2118
2119 // Hide sweeper thread from external view.
2120 bool is_hidden_from_external_view() const { return true; }
2121
2122 bool is_Code_cache_sweeper_thread() const { return true; }
2123
2124 // Prevent GC from unloading _scanned_compiled_method
2125 void oops_do(OopClosure* f, CodeBlobClosure* cf);
2126 void nmethods_do(CodeBlobClosure* cf);
2127 };
2128
2129 // A thread used for Compilation.
2130 class CompilerThread : public JavaThread {
2131 friend class VMStructs;
2132 private:
2133 CompilerCounters* _counters;
2134
2135 ciEnv* _env;
2136 CompileLog* _log;
2137 CompileTask* volatile _task; // print_threads_compiling can read this concurrently.
2138 CompileQueue* _queue;
2139 BufferBlob* _buffer_blob;
2140
2141 AbstractCompiler* _compiler;
2142 TimeStamp _idle_time;
2143
2144 public:
2145
2146 static CompilerThread* current();
2147
2148 CompilerThread(CompileQueue* queue, CompilerCounters* counters);
2149 ~CompilerThread();
2150
2151 bool is_Compiler_thread() const { return true; }
2152
2153 virtual bool can_call_java() const;
2154
2155 // Hide native compiler threads from external view.
2156 bool is_hidden_from_external_view() const { return !can_call_java(); }
2157
2158 void set_compiler(AbstractCompiler* c) { _compiler = c; }
2159 AbstractCompiler* compiler() const { return _compiler; }
2160
2161 CompileQueue* queue() const { return _queue; }
2162 CompilerCounters* counters() const { return _counters; }
2163
2164 // Get/set the thread's compilation environment.
2165 ciEnv* env() { return _env; }
2166 void set_env(ciEnv* env) { _env = env; }
2167
2168 BufferBlob* get_buffer_blob() const { return _buffer_blob; }
2169 void set_buffer_blob(BufferBlob* b) { _buffer_blob = b; }
2170
2171 // Get/set the thread's logging information
2172 CompileLog* log() { return _log; }
2173 void init_log(CompileLog* log) {
2174 // Set once, for good.
2175 assert(_log == NULL, "set only once");
2176 _log = log;
2177 }
2178
2179 void start_idle_timer() { _idle_time.update(); }
2180 jlong idle_time_millis() {
2181 return TimeHelper::counter_to_millis(_idle_time.ticks_since_update());
2182 }
2183
2184 #ifndef PRODUCT
2185 private:
2186 IdealGraphPrinter *_ideal_graph_printer;
2187 public:
2188 IdealGraphPrinter *ideal_graph_printer() { return _ideal_graph_printer; }
2189 void set_ideal_graph_printer(IdealGraphPrinter *n) { _ideal_graph_printer = n; }
2190 #endif
2191
2192 // Get/set the thread's current task
2193 CompileTask* task() { return _task; }
2194 void set_task(CompileTask* task) { _task = task; }
2195 };
2196
2197 inline CompilerThread* CompilerThread::current() {
2198 return JavaThread::current()->as_CompilerThread();
2199 }
2200
2201 // The active thread queue. It also keeps track of the current used
2202 // thread priorities.
2203 class Threads: AllStatic {
2204 friend class VMStructs;
2205 private:
2206 static JavaThread* _thread_list;
2207 static int _number_of_threads;
2208 static int _number_of_non_daemon_threads;
2209 static int _return_code;
2210 static int _thread_claim_parity;
2211 #ifdef ASSERT
2212 static bool _vm_complete;
2213 static size_t _threads_before_barrier_set;
2214 #endif
2215
2216 static void initialize_java_lang_classes(JavaThread* main_thread, TRAPS);
2217 static void initialize_jsr292_core_classes(TRAPS);
2218
2219 public:
2220 // Thread management
2221 // force_daemon is a concession to JNI, where we may need to add a
2222 // thread to the thread list before allocating its thread object
2223 static void add(JavaThread* p, bool force_daemon = false);
2224 static void remove(JavaThread* p);
2225 static void non_java_threads_do(ThreadClosure* tc);
2226 static void java_threads_do(ThreadClosure* tc);
2227 static void java_threads_and_vm_thread_do(ThreadClosure* tc);
2228 static void threads_do(ThreadClosure* tc);
2229 static void possibly_parallel_threads_do(bool is_par, ThreadClosure* tc);
2230
2231 // Initializes the vm and creates the vm thread
2232 static jint create_vm(JavaVMInitArgs* args, bool* canTryAgain);
2233 static void convert_vm_init_libraries_to_agents();
2234 static void create_vm_init_libraries();
2235 static void create_vm_init_agents();
2236 static void shutdown_vm_agents();
2237 static bool destroy_vm();
2238 // Supported VM versions via JNI
2239 // Includes JNI_VERSION_1_1
2240 static jboolean is_supported_jni_version_including_1_1(jint version);
2241 // Does not include JNI_VERSION_1_1
2242 static jboolean is_supported_jni_version(jint version);
2243
2244 // The "thread claim parity" provides a way for threads to be claimed
2245 // by parallel worker tasks.
2246 //
2247 // Each thread contains a a "parity" field. A task will claim the
2248 // thread only if its parity field is the same as the global parity,
2249 // which is updated by calling change_thread_claim_parity().
2250 //
2251 // For this to work change_thread_claim_parity() needs to be called
2252 // exactly once in sequential code before starting parallel tasks
2253 // that should claim threads.
2254 //
2255 // New threads get their parity set to 0 and change_thread_claim_parity()
2256 // never set the global parity to 0.
2257 static int thread_claim_parity() { return _thread_claim_parity; }
2258 static void change_thread_claim_parity();
2259 static void assert_all_threads_claimed() NOT_DEBUG_RETURN;
2260
2261 // Apply "f->do_oop" to all root oops in all threads.
2262 // This version may only be called by sequential code.
2263 static void oops_do(OopClosure* f, CodeBlobClosure* cf);
2264 // This version may be called by sequential or parallel code.
2265 static void possibly_parallel_oops_do(bool is_par, OopClosure* f, CodeBlobClosure* cf);
2266
2267 // Apply "f->do_oop" to roots in all threads that
2268 // are part of compiled frames
2269 static void compiled_frame_oops_do(OopClosure* f, CodeBlobClosure* cf);
2270
2271 static void convert_hcode_pointers();
2272 static void restore_hcode_pointers();
2273
2274 // Sweeper
2275 static void nmethods_do(CodeBlobClosure* cf);
2276
2277 // RedefineClasses support
2278 static void metadata_do(void f(Metadata*));
2279 static void metadata_handles_do(void f(Metadata*));
2280
2281 #ifdef ASSERT
2282 static bool is_vm_complete() { return _vm_complete; }
2283
2284 static size_t threads_before_barrier_set() {
2285 return _threads_before_barrier_set;
2286 }
2287
2288 static void inc_threads_before_barrier_set() {
2289 ++_threads_before_barrier_set;
2290 }
2291 #endif // ASSERT
2292
2293 // Verification
2294 static void verify();
2295 static void print_on(outputStream* st, bool print_stacks, bool internal_format, bool print_concurrent_locks, bool print_extended_info);
2296 static void print(bool print_stacks, bool internal_format) {
2297 // this function is only used by debug.cpp
2298 print_on(tty, print_stacks, internal_format, false /* no concurrent lock printed */, false /* simple format */);
2299 }
2300 static void print_on_error(outputStream* st, Thread* current, char* buf, int buflen);
2301 static void print_on_error(Thread* this_thread, outputStream* st, Thread* current, char* buf,
2302 int buflen, bool* found_current);
2303 static void print_threads_compiling(outputStream* st, char* buf, int buflen);
2304 static void print_vt_buffer_stats_on(outputStream* st);
2305
2306 // Get Java threads that are waiting to enter a monitor.
2307 static GrowableArray<JavaThread*>* get_pending_threads(ThreadsList * t_list,
2308 int count, address monitor);
2309
2310 // Get owning Java thread from the monitor's owner field.
2311 static JavaThread *owning_thread_from_monitor_owner(ThreadsList * t_list,
2312 address owner);
2313
2314 // Number of threads on the active threads list
2315 static int number_of_threads() { return _number_of_threads; }
2316 // Number of non-daemon threads on the active threads list
2317 static int number_of_non_daemon_threads() { return _number_of_non_daemon_threads; }
2318
2319 // Deoptimizes all frames tied to marked nmethods
2320 static void deoptimized_wrt_marked_nmethods();
2321 };
2322
2323
2324 // Thread iterator
2325 class ThreadClosure: public StackObj {
2326 public:
2327 virtual void do_thread(Thread* thread) = 0;
2328 };
2329
2330 class SignalHandlerMark: public StackObj {
2331 private:
2332 Thread* _thread;
2333 public:
2334 SignalHandlerMark(Thread* t) {
2335 _thread = t;
2336 if (_thread) _thread->enter_signal_handler();
2337 }
2338 ~SignalHandlerMark() {
2339 if (_thread) _thread->leave_signal_handler();
2340 _thread = NULL;
2341 }
2342 };
2343
2344
2345 #endif // SHARE_VM_RUNTIME_THREAD_HPP