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