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