1 /*
2 * Copyright (c) 1997, 2017, 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/threadLocalAllocBuffer.hpp"
30 #include "memory/allocation.hpp"
31 #include "oops/oop.hpp"
32 #include "prims/jvmtiExport.hpp"
33 #include "runtime/frame.hpp"
34 #include "runtime/handshake.hpp"
35 #include "runtime/javaFrameAnchor.hpp"
36 #include "runtime/jniHandles.hpp"
37 #include "runtime/mutexLocker.hpp"
38 #include "runtime/os.hpp"
39 #include "runtime/osThread.hpp"
40 #include "runtime/park.hpp"
41 #include "runtime/safepoint.hpp"
42 #include "runtime/stubRoutines.hpp"
43 #include "runtime/threadLocalStorage.hpp"
44 #include "runtime/thread_ext.hpp"
45 #include "runtime/unhandledOops.hpp"
46 #include "trace/traceBackend.hpp"
47 #include "trace/traceMacros.hpp"
48 #include "utilities/align.hpp"
49 #include "utilities/exceptions.hpp"
50 #include "utilities/macros.hpp"
51 #if INCLUDE_ALL_GCS
52 #include "gc/g1/dirtyCardQueue.hpp"
53 #include "gc/g1/satbMarkQueue.hpp"
54 #endif // INCLUDE_ALL_GCS
55 #ifdef ZERO
56 # include "stack_zero.hpp"
57 #endif
58
59 class ThreadSafepointState;
60 class ThreadsList;
61 class ThreadsSMRSupport;
62 class NestedThreadsList;
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 // Exception handling
117 // (Note: _pending_exception and friends are in ThreadShadow)
118 //oop _pending_exception; // pending exception for current thread
119 // const char* _exception_file; // file information for exception (debugging only)
120 // int _exception_line; // line information for exception (debugging only)
121 protected:
122 // Support for forcing alignment of thread objects for biased locking
123 void* _real_malloc_address;
124
125 // JavaThread lifecycle support:
126 friend class ScanHazardPtrGatherProtectedThreadsClosure; // for cmpxchg_threads_hazard_ptr(), get_threads_hazard_ptr(), is_hazard_ptr_tagged() access
127 friend class ScanHazardPtrGatherThreadsListClosure; // for get_nested_threads_hazard_ptr(), get_threads_hazard_ptr(), untag_hazard_ptr() access
128 friend class ScanHazardPtrPrintMatchingThreadsClosure; // for get_threads_hazard_ptr(), is_hazard_ptr_tagged() access
129 friend class ThreadsListSetter; // for get_threads_hazard_ptr() access
130 friend class ThreadsSMRSupport; // for get_threads_hazard_ptr() access
131
132 ThreadsList* volatile _threads_hazard_ptr;
133 ThreadsList* cmpxchg_threads_hazard_ptr(ThreadsList* exchange_value, ThreadsList* compare_value);
134 ThreadsList* get_threads_hazard_ptr();
135 void set_threads_hazard_ptr(ThreadsList* new_list);
136 static bool is_hazard_ptr_tagged(ThreadsList* list) {
137 return (intptr_t(list) & intptr_t(1)) == intptr_t(1);
138 }
139 static ThreadsList* tag_hazard_ptr(ThreadsList* list) {
140 return (ThreadsList*)(intptr_t(list) | intptr_t(1));
141 }
142 static ThreadsList* untag_hazard_ptr(ThreadsList* list) {
143 return (ThreadsList*)(intptr_t(list) & ~intptr_t(1));
144 }
145 NestedThreadsList* _nested_threads_hazard_ptr;
146 NestedThreadsList* get_nested_threads_hazard_ptr() {
147 return _nested_threads_hazard_ptr;
148 }
149 void set_nested_threads_hazard_ptr(NestedThreadsList* value) {
150 assert(Threads_lock->owned_by_self(),
151 "must own Threads_lock for _nested_threads_hazard_ptr to be valid.");
152 _nested_threads_hazard_ptr = value;
153 }
154 // This field is enabled via -XX:+EnableThreadSMRStatistics:
155 uint _nested_threads_hazard_ptr_cnt;
156 void dec_nested_threads_hazard_ptr_cnt() {
157 assert(_nested_threads_hazard_ptr_cnt != 0, "mismatched {dec,inc}_nested_threads_hazard_ptr_cnt()");
158 _nested_threads_hazard_ptr_cnt--;
159 }
160 void inc_nested_threads_hazard_ptr_cnt() {
161 _nested_threads_hazard_ptr_cnt++;
162 }
163 uint nested_threads_hazard_ptr_cnt() {
164 return _nested_threads_hazard_ptr_cnt;
165 }
166
167 public:
168 void* operator new(size_t size) throw() { return allocate(size, true); }
169 void* operator new(size_t size, const std::nothrow_t& nothrow_constant) throw() {
170 return allocate(size, false); }
171 void operator delete(void* p);
172
173 protected:
174 static void* allocate(size_t size, bool throw_excpt, MEMFLAGS flags = mtThread);
175 private:
176
177 // ***************************************************************
178 // Suspend and resume support
179 // ***************************************************************
180 //
181 // VM suspend/resume no longer exists - it was once used for various
182 // things including safepoints but was deprecated and finally removed
183 // in Java 7. Because VM suspension was considered "internal" Java-level
184 // suspension was considered "external", and this legacy naming scheme
185 // remains.
186 //
187 // External suspend/resume requests come from JVM_SuspendThread,
188 // JVM_ResumeThread, JVMTI SuspendThread, and finally JVMTI
189 // ResumeThread. External
190 // suspend requests cause _external_suspend to be set and external
191 // resume requests cause _external_suspend to be cleared.
192 // External suspend requests do not nest on top of other external
193 // suspend requests. The higher level APIs reject suspend requests
194 // for already suspended threads.
195 //
196 // The external_suspend
197 // flag is checked by has_special_runtime_exit_condition() and java thread
198 // will self-suspend when handle_special_runtime_exit_condition() is
199 // called. Most uses of the _thread_blocked state in JavaThreads are
200 // considered the same as being externally suspended; if the blocking
201 // condition lifts, the JavaThread will self-suspend. Other places
202 // where VM checks for external_suspend include:
203 // + mutex granting (do not enter monitors when thread is suspended)
204 // + state transitions from _thread_in_native
205 //
206 // In general, java_suspend() does not wait for an external suspend
207 // request to complete. When it returns, the only guarantee is that
208 // the _external_suspend field is true.
209 //
210 // wait_for_ext_suspend_completion() is used to wait for an external
211 // suspend request to complete. External suspend requests are usually
212 // followed by some other interface call that requires the thread to
213 // be quiescent, e.g., GetCallTrace(). By moving the "wait time" into
214 // the interface that requires quiescence, we give the JavaThread a
215 // chance to self-suspend before we need it to be quiescent. This
216 // improves overall suspend/query performance.
217 //
218 // _suspend_flags controls the behavior of java_ suspend/resume.
219 // It must be set under the protection of SR_lock. Read from the flag is
220 // OK without SR_lock as long as the value is only used as a hint.
221 // (e.g., check _external_suspend first without lock and then recheck
222 // inside SR_lock and finish the suspension)
223 //
224 // _suspend_flags is also overloaded for other "special conditions" so
225 // that a single check indicates whether any special action is needed
226 // eg. for async exceptions.
227 // -------------------------------------------------------------------
228 // Notes:
229 // 1. The suspend/resume logic no longer uses ThreadState in OSThread
230 // but we still update its value to keep other part of the system (mainly
231 // JVMTI) happy. ThreadState is legacy code (see notes in
232 // osThread.hpp).
233 //
234 // 2. It would be more natural if set_external_suspend() is private and
235 // part of java_suspend(), but that probably would affect the suspend/query
236 // performance. Need more investigation on this.
237
238 // suspend/resume lock: used for self-suspend
239 Monitor* _SR_lock;
240
241 protected:
242 enum SuspendFlags {
243 // NOTE: avoid using the sign-bit as cc generates different test code
244 // when the sign-bit is used, and sometimes incorrectly - see CR 6398077
245
246 _external_suspend = 0x20000000U, // thread is asked to self suspend
247 _ext_suspended = 0x40000000U, // thread has self-suspended
248 _deopt_suspend = 0x10000000U, // thread needs to self suspend for deopt
249
250 _has_async_exception = 0x00000001U, // there is a pending async exception
251 _critical_native_unlock = 0x00000002U, // Must call back to unlock JNI critical lock
252
253 _trace_flag = 0x00000004U // call tracing backend
254 };
255
256 // various suspension related flags - atomically updated
257 // overloaded for async exception checking in check_special_condition_for_native_trans.
258 volatile uint32_t _suspend_flags;
259
260 private:
261 int _num_nested_signal;
262
263 DEBUG_ONLY(bool _suspendible_thread;)
264
265 public:
266 void enter_signal_handler() { _num_nested_signal++; }
267 void leave_signal_handler() { _num_nested_signal--; }
268 bool is_inside_signal_handler() const { return _num_nested_signal > 0; }
269
270 #ifdef ASSERT
271 void set_suspendible_thread() {
272 _suspendible_thread = true;
273 }
274
275 void clear_suspendible_thread() {
276 _suspendible_thread = false;
277 }
278
279 bool is_suspendible_thread() { return _suspendible_thread; }
280 #endif
281
282 private:
283 // Active_handles points to a block of handles
284 JNIHandleBlock* _active_handles;
285
286 // One-element thread local free list
287 JNIHandleBlock* _free_handle_block;
288
289 // Point to the last handle mark
290 HandleMark* _last_handle_mark;
291
292 // The parity of the last strong_roots iteration in which this thread was
293 // claimed as a task.
294 int _oops_do_parity;
295
296 public:
297 void set_last_handle_mark(HandleMark* mark) { _last_handle_mark = mark; }
298 HandleMark* last_handle_mark() const { return _last_handle_mark; }
299 private:
300
301 // debug support for checking if code does allow safepoints or not
302 // GC points in the VM can happen because of allocation, invoking a VM operation, or blocking on
303 // mutex, or blocking on an object synchronizer (Java locking).
304 // If !allow_safepoint(), then an assertion failure will happen in any of the above cases
305 // If !allow_allocation(), then an assertion failure will happen during allocation
306 // (Hence, !allow_safepoint() => !allow_allocation()).
307 //
308 // The two classes NoSafepointVerifier and No_Allocation_Verifier are used to set these counters.
309 //
310 NOT_PRODUCT(int _allow_safepoint_count;) // If 0, thread allow a safepoint to happen
311 debug_only(int _allow_allocation_count;) // If 0, the thread is allowed to allocate oops.
312
313 // Used by SkipGCALot class.
314 NOT_PRODUCT(bool _skip_gcalot;) // Should we elide gc-a-lot?
315
316 friend class NoAllocVerifier;
317 friend class NoSafepointVerifier;
318 friend class PauseNoSafepointVerifier;
319 friend class GCLocker;
320
321 volatile void* _polling_page; // Thread local polling page
322
323 ThreadLocalAllocBuffer _tlab; // Thread-local eden
324 ThreadLocalAllocBuffer _gclab; // Thread-local allocation buffer for GC (e.g. evacuation)
325 jlong _allocated_bytes; // Cumulative number of bytes allocated on
326 // the Java heap
327 jlong _allocated_bytes_gclab; // Cumulative number of bytes allocated on
328 // the Java heap, in GCLABs
329
330 mutable TRACE_DATA _trace_data; // Thread-local data for tracing
331
332 ThreadExt _ext;
333
334 int _vm_operation_started_count; // VM_Operation support
335 int _vm_operation_completed_count; // VM_Operation support
336
337 char _oom_during_evac;
338
339 ObjectMonitor* _current_pending_monitor; // ObjectMonitor this thread
340 // is waiting to lock
341 bool _current_pending_monitor_is_from_java; // locking is from Java code
342
343 // ObjectMonitor on which this thread called Object.wait()
344 ObjectMonitor* _current_waiting_monitor;
345
346 // Private thread-local objectmonitor list - a simple cache organized as a SLL.
347 public:
348 ObjectMonitor* omFreeList;
349 int omFreeCount; // length of omFreeList
350 int omFreeProvision; // reload chunk size
351 ObjectMonitor* omInUseList; // SLL to track monitors in circulation
352 int omInUseCount; // length of omInUseList
353
354 #ifdef ASSERT
355 private:
356 bool _visited_for_critical_count;
357
358 public:
359 void set_visited_for_critical_count(bool z) { _visited_for_critical_count = z; }
360 bool was_visited_for_critical_count() const { return _visited_for_critical_count; }
361 #endif
362
363 public:
364 enum {
365 is_definitely_current_thread = true
366 };
367
368 // Constructor
369 Thread();
370 virtual ~Thread();
371
372 // Manage Thread::current()
373 void initialize_thread_current();
374 void clear_thread_current(); // TLS cleanup needed before threads terminate
375
376 public:
377 // thread entry point
378 virtual void run();
379
380 // Testers
381 virtual bool is_VM_thread() const { return false; }
382 virtual bool is_Java_thread() const { return false; }
383 virtual bool is_Compiler_thread() const { return false; }
384 virtual bool is_Code_cache_sweeper_thread() const { return false; }
385 virtual bool is_hidden_from_external_view() const { return false; }
386 virtual bool is_jvmti_agent_thread() const { return false; }
387 // True iff the thread can perform GC operations at a safepoint.
388 // Generally will be true only of VM thread and parallel GC WorkGang
389 // threads.
390 virtual bool is_GC_task_thread() const { return false; }
391 virtual bool is_Watcher_thread() const { return false; }
392 virtual bool is_ConcurrentGC_thread() const { return false; }
393 virtual bool is_Named_thread() const { return false; }
394 virtual bool is_Worker_thread() const { return false; }
395
396 // Can this thread make Java upcalls
397 virtual bool can_call_java() const { return false; }
398
399 // Casts
400 virtual WorkerThread* as_Worker_thread() const { return NULL; }
401
402 virtual char* name() const { return (char*)"Unknown thread"; }
403
404 // Returns the current thread (ASSERTS if NULL)
405 static inline Thread* current();
406 // Returns the current thread, or NULL if not attached
407 static inline Thread* current_or_null();
408 // Returns the current thread, or NULL if not attached, and is
409 // safe for use from signal-handlers
410 static inline Thread* current_or_null_safe();
411
412 // Common thread operations
413 #ifdef ASSERT
414 static void check_for_dangling_thread_pointer(Thread *thread);
415 #endif
416 static void set_priority(Thread* thread, ThreadPriority priority);
417 static ThreadPriority get_priority(const Thread* const thread);
418 static void start(Thread* thread);
419 static void interrupt(Thread* thr);
420 static bool is_interrupted(Thread* thr, bool clear_interrupted);
421
422 void set_native_thread_name(const char *name) {
423 assert(Thread::current() == this, "set_native_thread_name can only be called on the current thread");
424 os::set_native_thread_name(name);
425 }
426
427 ObjectMonitor** omInUseList_addr() { return (ObjectMonitor **)&omInUseList; }
428 Monitor* SR_lock() const { return _SR_lock; }
429
430 bool has_async_exception() const { return (_suspend_flags & _has_async_exception) != 0; }
431
432 inline void set_suspend_flag(SuspendFlags f);
433 inline void clear_suspend_flag(SuspendFlags f);
434
435 inline void set_has_async_exception();
436 inline void clear_has_async_exception();
437
438 bool do_critical_native_unlock() const { return (_suspend_flags & _critical_native_unlock) != 0; }
439
440 inline void set_critical_native_unlock();
441 inline void clear_critical_native_unlock();
442
443 inline void set_trace_flag();
444 inline void clear_trace_flag();
445
446 bool is_oom_during_evac() const;
447 void set_oom_during_evac(bool oom);
448
449 #ifdef ASSERT
450 bool is_evac_allowed() const;
451 void set_evac_allowed(bool evac_allowed);
452 #endif
453
454 // Support for Unhandled Oop detection
455 // Add the field for both, fastdebug and debug, builds to keep
456 // Thread's fields layout the same.
457 // Note: CHECK_UNHANDLED_OOPS is defined only for fastdebug build.
458 #ifdef CHECK_UNHANDLED_OOPS
459 private:
460 UnhandledOops* _unhandled_oops;
461 #elif defined(ASSERT)
462 private:
463 void* _unhandled_oops;
464 #endif
465 #ifdef CHECK_UNHANDLED_OOPS
466 public:
467 UnhandledOops* unhandled_oops() { return _unhandled_oops; }
468 // Mark oop safe for gc. It may be stack allocated but won't move.
469 void allow_unhandled_oop(oop *op) {
470 if (CheckUnhandledOops) unhandled_oops()->allow_unhandled_oop(op);
471 }
472 // Clear oops at safepoint so crashes point to unhandled oop violator
473 void clear_unhandled_oops() {
474 if (CheckUnhandledOops) unhandled_oops()->clear_unhandled_oops();
475 }
476 #endif // CHECK_UNHANDLED_OOPS
477
478 public:
479 #ifndef PRODUCT
480 bool skip_gcalot() { return _skip_gcalot; }
481 void set_skip_gcalot(bool v) { _skip_gcalot = v; }
482 #endif
483
484 // Installs a pending exception to be inserted later
485 static void send_async_exception(oop thread_oop, oop java_throwable);
486
487 // Resource area
488 ResourceArea* resource_area() const { return _resource_area; }
489 void set_resource_area(ResourceArea* area) { _resource_area = area; }
490
491 OSThread* osthread() const { return _osthread; }
492 void set_osthread(OSThread* thread) { _osthread = thread; }
493
494 // JNI handle support
495 JNIHandleBlock* active_handles() const { return _active_handles; }
496 void set_active_handles(JNIHandleBlock* block) { _active_handles = block; }
497 JNIHandleBlock* free_handle_block() const { return _free_handle_block; }
498 void set_free_handle_block(JNIHandleBlock* block) { _free_handle_block = block; }
499
500 // Internal handle support
501 HandleArea* handle_area() const { return _handle_area; }
502 void set_handle_area(HandleArea* area) { _handle_area = area; }
503
504 GrowableArray<Metadata*>* metadata_handles() const { return _metadata_handles; }
505 void set_metadata_handles(GrowableArray<Metadata*>* handles){ _metadata_handles = handles; }
506
507 // Thread-Local Allocation Buffer (TLAB) support
508 ThreadLocalAllocBuffer& tlab() { return _tlab; }
509 void initialize_tlab() {
510 if (UseTLAB) {
511 tlab().initialize(false);
512 gclab().initialize(true);
513 }
514 }
515
516 // Thread-Local GC Allocation Buffer (GCLAB) support
517 ThreadLocalAllocBuffer& gclab() { return _gclab; }
518
519 jlong allocated_bytes() { return _allocated_bytes; }
520 void set_allocated_bytes(jlong value) { _allocated_bytes = value; }
521 void incr_allocated_bytes(jlong size) { _allocated_bytes += size; }
522 inline jlong cooked_allocated_bytes();
523
524 jlong allocated_bytes_gclab() { return _allocated_bytes_gclab; }
525 void set_allocated_bytes_gclab(jlong value) { _allocated_bytes_gclab = value; }
526 void incr_allocated_bytes_gclab(jlong size) { _allocated_bytes_gclab += size; }
527
528 TRACE_DEFINE_THREAD_TRACE_DATA_OFFSET;
529 TRACE_DATA* trace_data() const { return &_trace_data; }
530 bool is_trace_suspend() { return (_suspend_flags & _trace_flag) != 0; }
531
532 const ThreadExt& ext() const { return _ext; }
533 ThreadExt& ext() { return _ext; }
534
535 // VM operation support
536 int vm_operation_ticket() { return ++_vm_operation_started_count; }
537 int vm_operation_completed_count() { return _vm_operation_completed_count; }
538 void increment_vm_operation_completed_count() { _vm_operation_completed_count++; }
539
540 // For tracking the heavyweight monitor the thread is pending on.
541 ObjectMonitor* current_pending_monitor() {
542 return _current_pending_monitor;
543 }
544 void set_current_pending_monitor(ObjectMonitor* monitor) {
545 _current_pending_monitor = monitor;
546 }
547 void set_current_pending_monitor_is_from_java(bool from_java) {
548 _current_pending_monitor_is_from_java = from_java;
549 }
550 bool current_pending_monitor_is_from_java() {
551 return _current_pending_monitor_is_from_java;
552 }
553
554 // For tracking the ObjectMonitor on which this thread called Object.wait()
555 ObjectMonitor* current_waiting_monitor() {
556 return _current_waiting_monitor;
557 }
558 void set_current_waiting_monitor(ObjectMonitor* monitor) {
559 _current_waiting_monitor = monitor;
560 }
561
562 // GC support
563 // Apply "f->do_oop" to all root oops in "this".
564 // Used by JavaThread::oops_do.
565 // Apply "cf->do_code_blob" (if !NULL) to all code blobs active in frames
566 virtual void oops_do(OopClosure* f, CodeBlobClosure* cf);
567
568 // Handles the parallel case for the method below.
569 private:
570 bool claim_oops_do_par_case(int collection_parity);
571 public:
572 // Requires that "collection_parity" is that of the current roots
573 // iteration. If "is_par" is false, sets the parity of "this" to
574 // "collection_parity", and returns "true". If "is_par" is true,
575 // uses an atomic instruction to set the current threads parity to
576 // "collection_parity", if it is not already. Returns "true" iff the
577 // calling thread does the update, this indicates that the calling thread
578 // has claimed the thread's stack as a root groop in the current
579 // collection.
580 bool claim_oops_do(bool is_par, int collection_parity) {
581 if (!is_par) {
582 _oops_do_parity = collection_parity;
583 return true;
584 } else {
585 return claim_oops_do_par_case(collection_parity);
586 }
587 }
588
589 // jvmtiRedefineClasses support
590 void metadata_handles_do(void f(Metadata*));
591
592 // Used by fast lock support
593 virtual bool is_lock_owned(address adr) const;
594
595 // Check if address is in the stack of the thread (not just for locks).
596 // Warning: the method can only be used on the running thread
597 bool is_in_stack(address adr) const;
598 // Check if address is in the usable part of the stack (excludes protected
599 // guard pages)
600 bool is_in_usable_stack(address adr) const;
601
602 // Sets this thread as starting thread. Returns failure if thread
603 // creation fails due to lack of memory, too many threads etc.
604 bool set_as_starting_thread();
605
606 protected:
607 // OS data associated with the thread
608 OSThread* _osthread; // Platform-specific thread information
609
610 // Thread local resource area for temporary allocation within the VM
611 ResourceArea* _resource_area;
612
613 DEBUG_ONLY(ResourceMark* _current_resource_mark;)
614
615 // Thread local handle area for allocation of handles within the VM
616 HandleArea* _handle_area;
617 GrowableArray<Metadata*>* _metadata_handles;
618
619 // Support for stack overflow handling, get_thread, etc.
620 address _stack_base;
621 size_t _stack_size;
622 uintptr_t _self_raw_id; // used by get_thread (mutable)
623 int _lgrp_id;
624
625 volatile void** polling_page_addr() { return &_polling_page; }
626
627 public:
628 // Stack overflow support
629 address stack_base() const { assert(_stack_base != NULL,"Sanity check"); return _stack_base; }
630 void set_stack_base(address base) { _stack_base = base; }
631 size_t stack_size() const { return _stack_size; }
632 void set_stack_size(size_t size) { _stack_size = size; }
633 address stack_end() const { return stack_base() - stack_size(); }
634 void record_stack_base_and_size();
635
636 bool on_local_stack(address adr) const {
637 // QQQ this has knowledge of direction, ought to be a stack method
638 return (_stack_base >= adr && adr >= stack_end());
639 }
640
641 uintptr_t self_raw_id() { return _self_raw_id; }
642 void set_self_raw_id(uintptr_t value) { _self_raw_id = value; }
643
644 int lgrp_id() const { return _lgrp_id; }
645 void set_lgrp_id(int value) { _lgrp_id = value; }
646
647 // Printing
648 virtual void print_on(outputStream* st) const;
649 virtual void print_nested_threads_hazard_ptrs_on(outputStream* st) const;
650 void print() const { print_on(tty); }
651 virtual void print_on_error(outputStream* st, char* buf, int buflen) const;
652 void print_value_on(outputStream* st) const;
653
654 // Debug-only code
655 #ifdef ASSERT
656 private:
657 // Deadlock detection support for Mutex locks. List of locks own by thread.
658 Monitor* _owned_locks;
659 // Mutex::set_owner_implementation is the only place where _owned_locks is modified,
660 // thus the friendship
661 friend class Mutex;
662 friend class Monitor;
663
664 public:
665 void print_owned_locks_on(outputStream* st) const;
666 void print_owned_locks() const { print_owned_locks_on(tty); }
667 Monitor* owned_locks() const { return _owned_locks; }
668 bool owns_locks() const { return owned_locks() != NULL; }
669 bool owns_locks_but_compiled_lock() const;
670 int oops_do_parity() const { return _oops_do_parity; }
671
672 // Deadlock detection
673 bool allow_allocation() { return _allow_allocation_count == 0; }
674 ResourceMark* current_resource_mark() { return _current_resource_mark; }
675 void set_current_resource_mark(ResourceMark* rm) { _current_resource_mark = rm; }
676 #endif
677
678 void check_for_valid_safepoint_state(bool potential_vm_operation) PRODUCT_RETURN;
679
680 private:
681 volatile int _jvmti_env_iteration_count;
682
683 public:
684 void entering_jvmti_env_iteration() { ++_jvmti_env_iteration_count; }
685 void leaving_jvmti_env_iteration() { --_jvmti_env_iteration_count; }
686 bool is_inside_jvmti_env_iteration() { return _jvmti_env_iteration_count > 0; }
687
688 // Code generation
689 static ByteSize exception_file_offset() { return byte_offset_of(Thread, _exception_file); }
690 static ByteSize exception_line_offset() { return byte_offset_of(Thread, _exception_line); }
691 static ByteSize active_handles_offset() { return byte_offset_of(Thread, _active_handles); }
692
693 static ByteSize stack_base_offset() { return byte_offset_of(Thread, _stack_base); }
694 static ByteSize stack_size_offset() { return byte_offset_of(Thread, _stack_size); }
695
696 static ByteSize polling_page_offset() { return byte_offset_of(Thread, _polling_page); }
697
698 #define TLAB_FIELD_OFFSET(name) \
699 static ByteSize tlab_##name##_offset() { return byte_offset_of(Thread, _tlab) + ThreadLocalAllocBuffer::name##_offset(); }
700
701 TLAB_FIELD_OFFSET(start)
702 TLAB_FIELD_OFFSET(end)
703 TLAB_FIELD_OFFSET(top)
704 TLAB_FIELD_OFFSET(pf_top)
705 TLAB_FIELD_OFFSET(size) // desired_size
706 TLAB_FIELD_OFFSET(refill_waste_limit)
707 TLAB_FIELD_OFFSET(number_of_refills)
708 TLAB_FIELD_OFFSET(fast_refill_waste)
709 TLAB_FIELD_OFFSET(slow_allocations)
710
711 #undef TLAB_FIELD_OFFSET
712
713 static ByteSize gclab_start_offset() { return byte_offset_of(Thread, _gclab) + ThreadLocalAllocBuffer::start_offset(); }
714 static ByteSize gclab_top_offset() { return byte_offset_of(Thread, _gclab) + ThreadLocalAllocBuffer::top_offset(); }
715 static ByteSize gclab_end_offset() { return byte_offset_of(Thread, _gclab) + ThreadLocalAllocBuffer::end_offset(); }
716
717 static ByteSize allocated_bytes_offset() { return byte_offset_of(Thread, _allocated_bytes); }
718
719 public:
720 volatile intptr_t _Stalled;
721 volatile int _TypeTag;
722 ParkEvent * _ParkEvent; // for synchronized()
723 ParkEvent * _SleepEvent; // for Thread.sleep
724 ParkEvent * _MutexEvent; // for native internal Mutex/Monitor
725 ParkEvent * _MuxEvent; // for low-level muxAcquire-muxRelease
726 int NativeSyncRecursion; // diagnostic
727
728 volatile int _OnTrap; // Resume-at IP delta
729 jint _hashStateW; // Marsaglia Shift-XOR thread-local RNG
730 jint _hashStateX; // thread-specific hashCode generator state
731 jint _hashStateY;
732 jint _hashStateZ;
733 void * _schedctl;
734
735
736 volatile jint rng[4]; // RNG for spin loop
737
738 // Low-level leaf-lock primitives used to implement synchronization
739 // and native monitor-mutex infrastructure.
740 // Not for general synchronization use.
741 static void SpinAcquire(volatile int * Lock, const char * Name);
742 static void SpinRelease(volatile int * Lock);
743 static void muxAcquire(volatile intptr_t * Lock, const char * Name);
744 static void muxAcquireW(volatile intptr_t * Lock, ParkEvent * ev);
745 static void muxRelease(volatile intptr_t * Lock);
746 };
747
748 // Inline implementation of Thread::current()
749 inline Thread* Thread::current() {
750 Thread* current = current_or_null();
751 assert(current != NULL, "Thread::current() called on detached thread");
752 return current;
753 }
754
755 inline Thread* Thread::current_or_null() {
756 #ifndef USE_LIBRARY_BASED_TLS_ONLY
757 return _thr_current;
758 #else
759 if (ThreadLocalStorage::is_initialized()) {
760 return ThreadLocalStorage::thread();
761 }
762 return NULL;
763 #endif
764 }
765
766 inline Thread* Thread::current_or_null_safe() {
767 if (ThreadLocalStorage::is_initialized()) {
768 return ThreadLocalStorage::thread();
769 }
770 return NULL;
771 }
772
773 // Name support for threads. non-JavaThread subclasses with multiple
774 // uniquely named instances should derive from this.
775 class NamedThread: public Thread {
776 friend class VMStructs;
777 enum {
778 max_name_len = 64
779 };
780 private:
781 char* _name;
782 // log JavaThread being processed by oops_do
783 JavaThread* _processed_thread;
784 uint _gc_id; // The current GC id when a thread takes part in GC
785
786 public:
787 NamedThread();
788 ~NamedThread();
789 // May only be called once per thread.
790 void set_name(const char* format, ...) ATTRIBUTE_PRINTF(2, 3);
791 void initialize_named_thread();
792 virtual bool is_Named_thread() const { return true; }
793 virtual char* name() const { return _name == NULL ? (char*)"Unknown Thread" : _name; }
794 JavaThread *processed_thread() { return _processed_thread; }
795 void set_processed_thread(JavaThread *thread) { _processed_thread = thread; }
796 virtual void print_on(outputStream* st) const;
797
798 void set_gc_id(uint gc_id) { _gc_id = gc_id; }
799 uint gc_id() { return _gc_id; }
800 };
801
802 // Worker threads are named and have an id of an assigned work.
803 class WorkerThread: public NamedThread {
804 private:
805 uint _id;
806 public:
807 WorkerThread() : _id(0) { }
808 virtual bool is_Worker_thread() const { return true; }
809
810 virtual WorkerThread* as_Worker_thread() const {
811 assert(is_Worker_thread(), "Dubious cast to WorkerThread*?");
812 return (WorkerThread*) this;
813 }
814
815 void set_id(uint work_id) { _id = work_id; }
816 uint id() const { return _id; }
817 };
818
819 // A single WatcherThread is used for simulating timer interrupts.
820 class WatcherThread: public Thread {
821 friend class VMStructs;
822 public:
823 virtual void run();
824
825 private:
826 static WatcherThread* _watcher_thread;
827
828 static bool _startable;
829 // volatile due to at least one lock-free read
830 volatile static bool _should_terminate;
831 public:
832 enum SomeConstants {
833 delay_interval = 10 // interrupt delay in milliseconds
834 };
835
836 // Constructor
837 WatcherThread();
838
839 // No destruction allowed
840 ~WatcherThread() {
841 guarantee(false, "WatcherThread deletion must fix the race with VM termination");
842 }
843
844 // Tester
845 bool is_Watcher_thread() const { return true; }
846
847 // Printing
848 char* name() const { return (char*)"VM Periodic Task Thread"; }
849 void print_on(outputStream* st) const;
850 void unpark();
851
852 // Returns the single instance of WatcherThread
853 static WatcherThread* watcher_thread() { return _watcher_thread; }
854
855 // Create and start the single instance of WatcherThread, or stop it on shutdown
856 static void start();
857 static void stop();
858 // Only allow start once the VM is sufficiently initialized
859 // Otherwise the first task to enroll will trigger the start
860 static void make_startable();
861 private:
862 int sleep() const;
863 };
864
865
866 class CompilerThread;
867
868 typedef void (*ThreadFunction)(JavaThread*, TRAPS);
869
870 class JavaThread: public Thread {
871 friend class VMStructs;
872 friend class JVMCIVMStructs;
873 friend class WhiteBox;
874 private:
875 JavaThread* _next; // The next thread in the Threads list
876 bool _on_thread_list; // Is set when this JavaThread is added to the Threads list
877 oop _threadObj; // The Java level thread object
878
879 #ifdef ASSERT
880 private:
881 int _java_call_counter;
882
883 public:
884 int java_call_counter() { return _java_call_counter; }
885 void inc_java_call_counter() { _java_call_counter++; }
886 void dec_java_call_counter() {
887 assert(_java_call_counter > 0, "Invalid nesting of JavaCallWrapper");
888 _java_call_counter--;
889 }
890 private: // restore original namespace restriction
891 #endif // ifdef ASSERT
892
893 #ifndef PRODUCT
894 public:
895 enum {
896 jump_ring_buffer_size = 16
897 };
898 private: // restore original namespace restriction
899 #endif
900
901 JavaFrameAnchor _anchor; // Encapsulation of current java frame and it state
902
903 ThreadFunction _entry_point;
904
905 JNIEnv _jni_environment;
906
907 // Deopt support
908 DeoptResourceMark* _deopt_mark; // Holds special ResourceMark for deoptimization
909
910 intptr_t* _must_deopt_id; // id of frame that needs to be deopted once we
911 // transition out of native
912 CompiledMethod* _deopt_nmethod; // CompiledMethod that is currently being deoptimized
913 vframeArray* _vframe_array_head; // Holds the heap of the active vframeArrays
914 vframeArray* _vframe_array_last; // Holds last vFrameArray we popped
915 // Because deoptimization is lazy we must save jvmti requests to set locals
916 // in compiled frames until we deoptimize and we have an interpreter frame.
917 // This holds the pointer to array (yeah like there might be more than one) of
918 // description of compiled vframes that have locals that need to be updated.
919 GrowableArray<jvmtiDeferredLocalVariableSet*>* _deferred_locals_updates;
920
921 // Handshake value for fixing 6243940. We need a place for the i2c
922 // adapter to store the callee Method*. This value is NEVER live
923 // across a gc point so it does NOT have to be gc'd
924 // The handshake is open ended since we can't be certain that it will
925 // be NULLed. This is because we rarely ever see the race and end up
926 // in handle_wrong_method which is the backend of the handshake. See
927 // code in i2c adapters and handle_wrong_method.
928
929 Method* _callee_target;
930
931 // Used to pass back results to the interpreter or generated code running Java code.
932 oop _vm_result; // oop result is GC-preserved
933 Metadata* _vm_result_2; // non-oop result
934
935 // See ReduceInitialCardMarks: this holds the precise space interval of
936 // the most recent slow path allocation for which compiled code has
937 // elided card-marks for performance along the fast-path.
938 MemRegion _deferred_card_mark;
939
940 MonitorChunk* _monitor_chunks; // Contains the off stack monitors
941 // allocated during deoptimization
942 // and by JNI_MonitorEnter/Exit
943
944 // Async. requests support
945 enum AsyncRequests {
946 _no_async_condition = 0,
947 _async_exception,
948 _async_unsafe_access_error
949 };
950 AsyncRequests _special_runtime_exit_condition; // Enum indicating pending async. request
951 oop _pending_async_exception;
952
953 // Safepoint support
954 public: // Expose _thread_state for SafeFetchInt()
955 volatile JavaThreadState _thread_state;
956 private:
957 ThreadSafepointState *_safepoint_state; // Holds information about a thread during a safepoint
958 address _saved_exception_pc; // Saved pc of instruction where last implicit exception happened
959
960 // JavaThread termination support
961 enum TerminatedTypes {
962 _not_terminated = 0xDEAD - 2,
963 _thread_exiting, // JavaThread::exit() has been called for this thread
964 _thread_terminated, // JavaThread is removed from thread list
965 _vm_exited // JavaThread is still executing native code, but VM is terminated
966 // only VM_Exit can set _vm_exited
967 };
968
969 // In general a JavaThread's _terminated field transitions as follows:
970 //
971 // _not_terminated => _thread_exiting => _thread_terminated
972 //
973 // _vm_exited is a special value to cover the case of a JavaThread
974 // executing native code after the VM itself is terminated.
975 volatile TerminatedTypes _terminated;
976 // suspend/resume support
977 volatile bool _suspend_equivalent; // Suspend equivalent condition
978 jint _in_deopt_handler; // count of deoptimization
979 // handlers thread is in
980 volatile bool _doing_unsafe_access; // Thread may fault due to unsafe access
981 bool _do_not_unlock_if_synchronized; // Do not unlock the receiver of a synchronized method (since it was
982 // never locked) when throwing an exception. Used by interpreter only.
983
984 // JNI attach states:
985 enum JNIAttachStates {
986 _not_attaching_via_jni = 1, // thread is not attaching via JNI
987 _attaching_via_jni, // thread is attaching via JNI
988 _attached_via_jni // thread has attached via JNI
989 };
990
991 // A regular JavaThread's _jni_attach_state is _not_attaching_via_jni.
992 // A native thread that is attaching via JNI starts with a value
993 // of _attaching_via_jni and transitions to _attached_via_jni.
994 volatile JNIAttachStates _jni_attach_state;
995
996 public:
997 // State of the stack guard pages for this thread.
998 enum StackGuardState {
999 stack_guard_unused, // not needed
1000 stack_guard_reserved_disabled,
1001 stack_guard_yellow_reserved_disabled,// disabled (temporarily) after stack overflow
1002 stack_guard_enabled // enabled
1003 };
1004
1005 private:
1006
1007 #if INCLUDE_JVMCI
1008 // The _pending_* fields below are used to communicate extra information
1009 // from an uncommon trap in JVMCI compiled code to the uncommon trap handler.
1010
1011 // Communicates the DeoptReason and DeoptAction of the uncommon trap
1012 int _pending_deoptimization;
1013
1014 // Specifies whether the uncommon trap is to bci 0 of a synchronized method
1015 // before the monitor has been acquired.
1016 bool _pending_monitorenter;
1017
1018 // Specifies if the DeoptReason for the last uncommon trap was Reason_transfer_to_interpreter
1019 bool _pending_transfer_to_interpreter;
1020
1021 // Guard for re-entrant call to JVMCIRuntime::adjust_comp_level
1022 bool _adjusting_comp_level;
1023
1024 // An object that JVMCI compiled code can use to further describe and
1025 // uniquely identify the speculative optimization guarded by the uncommon trap
1026 oop _pending_failed_speculation;
1027
1028 // These fields are mutually exclusive in terms of live ranges.
1029 union {
1030 // Communicates the pc at which the most recent implicit exception occurred
1031 // from the signal handler to a deoptimization stub.
1032 address _implicit_exception_pc;
1033
1034 // Communicates an alternative call target to an i2c stub from a JavaCall .
1035 address _alternate_call_target;
1036 } _jvmci;
1037
1038 // Support for high precision, thread sensitive counters in JVMCI compiled code.
1039 jlong* _jvmci_counters;
1040
1041 public:
1042 static jlong* _jvmci_old_thread_counters;
1043 static void collect_counters(typeArrayOop array);
1044 private:
1045 #endif // INCLUDE_JVMCI
1046
1047 StackGuardState _stack_guard_state;
1048
1049 // Precompute the limit of the stack as used in stack overflow checks.
1050 // We load it from here to simplify the stack overflow check in assembly.
1051 address _stack_overflow_limit;
1052 address _reserved_stack_activation;
1053
1054 // Compiler exception handling (NOTE: The _exception_oop is *NOT* the same as _pending_exception. It is
1055 // used to temp. parsing values into and out of the runtime system during exception handling for compiled
1056 // code)
1057 volatile oop _exception_oop; // Exception thrown in compiled code
1058 volatile address _exception_pc; // PC where exception happened
1059 volatile address _exception_handler_pc; // PC for handler of exception
1060 volatile int _is_method_handle_return; // true (== 1) if the current exception PC is a MethodHandle call site.
1061
1062 private:
1063 // support for JNI critical regions
1064 jint _jni_active_critical; // count of entries into JNI critical region
1065
1066 // Checked JNI: function name requires exception check
1067 char* _pending_jni_exception_check_fn;
1068
1069 // For deadlock detection.
1070 int _depth_first_number;
1071
1072 // JVMTI PopFrame support
1073 // This is set to popframe_pending to signal that top Java frame should be popped immediately
1074 int _popframe_condition;
1075
1076 // If reallocation of scalar replaced objects fails, we throw OOM
1077 // and during exception propagation, pop the top
1078 // _frames_to_pop_failed_realloc frames, the ones that reference
1079 // failed reallocations.
1080 int _frames_to_pop_failed_realloc;
1081
1082 #ifndef PRODUCT
1083 int _jmp_ring_index;
1084 struct {
1085 // We use intptr_t instead of address so debugger doesn't try and display strings
1086 intptr_t _target;
1087 intptr_t _instruction;
1088 const char* _file;
1089 int _line;
1090 } _jmp_ring[jump_ring_buffer_size];
1091 #endif // PRODUCT
1092
1093 #if INCLUDE_ALL_GCS
1094 // Support for G1 barriers
1095
1096 SATBMarkQueue _satb_mark_queue; // Thread-local log for SATB barrier.
1097 // Set of all such queues.
1098 static SATBMarkQueueSet _satb_mark_queue_set;
1099
1100 DirtyCardQueue _dirty_card_queue; // Thread-local log for dirty cards.
1101 // Set of all such queues.
1102 static DirtyCardQueueSet _dirty_card_queue_set;
1103
1104 void flush_barrier_queues();
1105
1106 // Support for Shenandoah barriers
1107 static char _gc_state_global;
1108 char _gc_state;
1109
1110 #endif // INCLUDE_ALL_GCS
1111
1112 friend class VMThread;
1113 friend class ThreadWaitTransition;
1114 friend class VM_Exit;
1115
1116 void initialize(); // Initialized the instance variables
1117
1118 public:
1119 // Constructor
1120 JavaThread(bool is_attaching_via_jni = false); // for main thread and JNI attached threads
1121 JavaThread(ThreadFunction entry_point, size_t stack_size = 0);
1122 ~JavaThread();
1123
1124 #ifdef ASSERT
1125 // verify this JavaThread hasn't be published in the Threads::list yet
1126 void verify_not_published();
1127 #endif
1128
1129 //JNI functiontable getter/setter for JVMTI jni function table interception API.
1130 void set_jni_functions(struct JNINativeInterface_* functionTable) {
1131 _jni_environment.functions = functionTable;
1132 }
1133 struct JNINativeInterface_* get_jni_functions() {
1134 return (struct JNINativeInterface_ *)_jni_environment.functions;
1135 }
1136
1137 // This function is called at thread creation to allow
1138 // platform specific thread variables to be initialized.
1139 void cache_global_variables();
1140
1141 // Executes Shutdown.shutdown()
1142 void invoke_shutdown_hooks();
1143
1144 // Cleanup on thread exit
1145 enum ExitType {
1146 normal_exit,
1147 jni_detach
1148 };
1149 void exit(bool destroy_vm, ExitType exit_type = normal_exit);
1150
1151 void cleanup_failed_attach_current_thread();
1152
1153 // Testers
1154 virtual bool is_Java_thread() const { return true; }
1155 virtual bool can_call_java() const { return true; }
1156
1157 // Thread chain operations
1158 JavaThread* next() const { return _next; }
1159 void set_next(JavaThread* p) { _next = p; }
1160
1161 // Thread oop. threadObj() can be NULL for initial JavaThread
1162 // (or for threads attached via JNI)
1163 oop threadObj() const { return _threadObj; }
1164 void set_threadObj(oop p) { _threadObj = p; }
1165
1166 ThreadPriority java_priority() const; // Read from threadObj()
1167
1168 // Prepare thread and add to priority queue. If a priority is
1169 // not specified, use the priority of the thread object. Threads_lock
1170 // must be held while this function is called.
1171 void prepare(jobject jni_thread, ThreadPriority prio=NoPriority);
1172 void prepare_ext();
1173
1174 void set_saved_exception_pc(address pc) { _saved_exception_pc = pc; }
1175 address saved_exception_pc() { return _saved_exception_pc; }
1176
1177
1178 ThreadFunction entry_point() const { return _entry_point; }
1179
1180 // Allocates a new Java level thread object for this thread. thread_name may be NULL.
1181 void allocate_threadObj(Handle thread_group, const char* thread_name, bool daemon, TRAPS);
1182
1183 // Last frame anchor routines
1184
1185 JavaFrameAnchor* frame_anchor(void) { return &_anchor; }
1186
1187 // last_Java_sp
1188 bool has_last_Java_frame() const { return _anchor.has_last_Java_frame(); }
1189 intptr_t* last_Java_sp() const { return _anchor.last_Java_sp(); }
1190
1191 // last_Java_pc
1192
1193 address last_Java_pc(void) { return _anchor.last_Java_pc(); }
1194
1195 // Safepoint support
1196 #if !(defined(PPC64) || defined(AARCH64))
1197 JavaThreadState thread_state() const { return _thread_state; }
1198 void set_thread_state(JavaThreadState s) { _thread_state = s; }
1199 #else
1200 // Use membars when accessing volatile _thread_state. See
1201 // Threads::create_vm() for size checks.
1202 inline JavaThreadState thread_state() const;
1203 inline void set_thread_state(JavaThreadState s);
1204 #endif
1205 ThreadSafepointState *safepoint_state() const { return _safepoint_state; }
1206 void set_safepoint_state(ThreadSafepointState *state) { _safepoint_state = state; }
1207 bool is_at_poll_safepoint() { return _safepoint_state->is_at_poll_safepoint(); }
1208
1209 // JavaThread termination and lifecycle support:
1210 void smr_delete();
1211 bool on_thread_list() const { return _on_thread_list; }
1212 void set_on_thread_list() { _on_thread_list = true; }
1213
1214 // thread has called JavaThread::exit() or is terminated
1215 bool is_exiting() const;
1216 // thread is terminated (no longer on the threads list); we compare
1217 // against the two non-terminated values so that a freed JavaThread
1218 // will also be considered terminated.
1219 bool check_is_terminated(TerminatedTypes l_terminated) const {
1220 return l_terminated != _not_terminated && l_terminated != _thread_exiting;
1221 }
1222 bool is_terminated() const;
1223 void set_terminated(TerminatedTypes t);
1224 // special for Threads::remove() which is static:
1225 void set_terminated_value();
1226 void block_if_vm_exited();
1227
1228 bool doing_unsafe_access() { return _doing_unsafe_access; }
1229 void set_doing_unsafe_access(bool val) { _doing_unsafe_access = val; }
1230
1231 bool do_not_unlock_if_synchronized() { return _do_not_unlock_if_synchronized; }
1232 void set_do_not_unlock_if_synchronized(bool val) { _do_not_unlock_if_synchronized = val; }
1233
1234 inline void set_polling_page(void* poll_value);
1235 inline volatile void* get_polling_page();
1236
1237 private:
1238 // Support for thread handshake operations
1239 HandshakeState _handshake;
1240 public:
1241 void set_handshake_operation(HandshakeOperation* op) {
1242 _handshake.set_operation(this, op);
1243 }
1244
1245 bool has_handshake() const {
1246 return _handshake.has_operation();
1247 }
1248
1249 void cancel_handshake() {
1250 _handshake.cancel(this);
1251 }
1252
1253 void handshake_process_by_self() {
1254 _handshake.process_by_self(this);
1255 }
1256
1257 void handshake_process_by_vmthread() {
1258 _handshake.process_by_vmthread(this);
1259 }
1260
1261 // Suspend/resume support for JavaThread
1262 private:
1263 inline void set_ext_suspended();
1264 inline void clear_ext_suspended();
1265
1266 public:
1267 void java_suspend();
1268 void java_resume();
1269 int java_suspend_self();
1270
1271 void check_and_wait_while_suspended() {
1272 assert(JavaThread::current() == this, "sanity check");
1273
1274 bool do_self_suspend;
1275 do {
1276 // were we externally suspended while we were waiting?
1277 do_self_suspend = handle_special_suspend_equivalent_condition();
1278 if (do_self_suspend) {
1279 // don't surprise the thread that suspended us by returning
1280 java_suspend_self();
1281 set_suspend_equivalent();
1282 }
1283 } while (do_self_suspend);
1284 }
1285 static void check_safepoint_and_suspend_for_native_trans(JavaThread *thread);
1286 // Check for async exception in addition to safepoint and suspend request.
1287 static void check_special_condition_for_native_trans(JavaThread *thread);
1288
1289 // Same as check_special_condition_for_native_trans but finishes the
1290 // transition into thread_in_Java mode so that it can potentially
1291 // block.
1292 static void check_special_condition_for_native_trans_and_transition(JavaThread *thread);
1293
1294 bool is_ext_suspend_completed(bool called_by_wait, int delay, uint32_t *bits);
1295 bool is_ext_suspend_completed_with_lock(uint32_t *bits) {
1296 MutexLockerEx ml(SR_lock(), Mutex::_no_safepoint_check_flag);
1297 // Warning: is_ext_suspend_completed() may temporarily drop the
1298 // SR_lock to allow the thread to reach a stable thread state if
1299 // it is currently in a transient thread state.
1300 return is_ext_suspend_completed(false /* !called_by_wait */,
1301 SuspendRetryDelay, bits);
1302 }
1303
1304 // We cannot allow wait_for_ext_suspend_completion() to run forever or
1305 // we could hang. SuspendRetryCount and SuspendRetryDelay are normally
1306 // passed as the count and delay parameters. Experiments with specific
1307 // calls to wait_for_ext_suspend_completion() can be done by passing
1308 // other values in the code. Experiments with all calls can be done
1309 // via the appropriate -XX options.
1310 bool wait_for_ext_suspend_completion(int count, int delay, uint32_t *bits);
1311
1312 // test for suspend - most (all?) of these should go away
1313 bool is_thread_fully_suspended(bool wait_for_suspend, uint32_t *bits);
1314
1315 inline void set_external_suspend();
1316 inline void clear_external_suspend();
1317
1318 inline void set_deopt_suspend();
1319 inline void clear_deopt_suspend();
1320 bool is_deopt_suspend() { return (_suspend_flags & _deopt_suspend) != 0; }
1321
1322 bool is_external_suspend() const {
1323 return (_suspend_flags & _external_suspend) != 0;
1324 }
1325 // Whenever a thread transitions from native to vm/java it must suspend
1326 // if external|deopt suspend is present.
1327 bool is_suspend_after_native() const {
1328 return (_suspend_flags & (_external_suspend | _deopt_suspend)) != 0;
1329 }
1330
1331 // external suspend request is completed
1332 bool is_ext_suspended() const {
1333 return (_suspend_flags & _ext_suspended) != 0;
1334 }
1335
1336 bool is_external_suspend_with_lock() const {
1337 MutexLockerEx ml(SR_lock(), Mutex::_no_safepoint_check_flag);
1338 return is_external_suspend();
1339 }
1340
1341 // Special method to handle a pending external suspend request
1342 // when a suspend equivalent condition lifts.
1343 bool handle_special_suspend_equivalent_condition() {
1344 assert(is_suspend_equivalent(),
1345 "should only be called in a suspend equivalence condition");
1346 MutexLockerEx ml(SR_lock(), Mutex::_no_safepoint_check_flag);
1347 bool ret = is_external_suspend();
1348 if (!ret) {
1349 // not about to self-suspend so clear suspend equivalence
1350 clear_suspend_equivalent();
1351 }
1352 // implied else:
1353 // We have a pending external suspend request so we leave the
1354 // suspend_equivalent flag set until java_suspend_self() sets
1355 // the ext_suspended flag and clears the suspend_equivalent
1356 // flag. This insures that wait_for_ext_suspend_completion()
1357 // will return consistent values.
1358 return ret;
1359 }
1360
1361 // utility methods to see if we are doing some kind of suspension
1362 bool is_being_ext_suspended() const {
1363 MutexLockerEx ml(SR_lock(), Mutex::_no_safepoint_check_flag);
1364 return is_ext_suspended() || is_external_suspend();
1365 }
1366
1367 bool is_suspend_equivalent() const { return _suspend_equivalent; }
1368
1369 void set_suspend_equivalent() { _suspend_equivalent = true; }
1370 void clear_suspend_equivalent() { _suspend_equivalent = false; }
1371
1372 // Thread.stop support
1373 void send_thread_stop(oop throwable);
1374 AsyncRequests clear_special_runtime_exit_condition() {
1375 AsyncRequests x = _special_runtime_exit_condition;
1376 _special_runtime_exit_condition = _no_async_condition;
1377 return x;
1378 }
1379
1380 // Are any async conditions present?
1381 bool has_async_condition() { return (_special_runtime_exit_condition != _no_async_condition); }
1382
1383 void check_and_handle_async_exceptions(bool check_unsafe_error = true);
1384
1385 // these next two are also used for self-suspension and async exception support
1386 void handle_special_runtime_exit_condition(bool check_asyncs = true);
1387
1388 // Return true if JavaThread has an asynchronous condition or
1389 // if external suspension is requested.
1390 bool has_special_runtime_exit_condition() {
1391 // Because we don't use is_external_suspend_with_lock
1392 // it is possible that we won't see an asynchronous external suspend
1393 // request that has just gotten started, i.e., SR_lock grabbed but
1394 // _external_suspend field change either not made yet or not visible
1395 // yet. However, this is okay because the request is asynchronous and
1396 // we will see the new flag value the next time through. It's also
1397 // possible that the external suspend request is dropped after
1398 // we have checked is_external_suspend(), we will recheck its value
1399 // under SR_lock in java_suspend_self().
1400 return (_special_runtime_exit_condition != _no_async_condition) ||
1401 is_external_suspend() || is_trace_suspend();
1402 }
1403
1404 void set_pending_unsafe_access_error() { _special_runtime_exit_condition = _async_unsafe_access_error; }
1405
1406 inline void set_pending_async_exception(oop e);
1407
1408 // Fast-locking support
1409 bool is_lock_owned(address adr) const;
1410
1411 // Accessors for vframe array top
1412 // The linked list of vframe arrays are sorted on sp. This means when we
1413 // unpack the head must contain the vframe array to unpack.
1414 void set_vframe_array_head(vframeArray* value) { _vframe_array_head = value; }
1415 vframeArray* vframe_array_head() const { return _vframe_array_head; }
1416
1417 // Side structure for deferring update of java frame locals until deopt occurs
1418 GrowableArray<jvmtiDeferredLocalVariableSet*>* deferred_locals() const { return _deferred_locals_updates; }
1419 void set_deferred_locals(GrowableArray<jvmtiDeferredLocalVariableSet *>* vf) { _deferred_locals_updates = vf; }
1420
1421 // These only really exist to make debugging deopt problems simpler
1422
1423 void set_vframe_array_last(vframeArray* value) { _vframe_array_last = value; }
1424 vframeArray* vframe_array_last() const { return _vframe_array_last; }
1425
1426 // The special resourceMark used during deoptimization
1427
1428 void set_deopt_mark(DeoptResourceMark* value) { _deopt_mark = value; }
1429 DeoptResourceMark* deopt_mark(void) { return _deopt_mark; }
1430
1431 intptr_t* must_deopt_id() { return _must_deopt_id; }
1432 void set_must_deopt_id(intptr_t* id) { _must_deopt_id = id; }
1433 void clear_must_deopt_id() { _must_deopt_id = NULL; }
1434
1435 void set_deopt_compiled_method(CompiledMethod* nm) { _deopt_nmethod = nm; }
1436 CompiledMethod* deopt_compiled_method() { return _deopt_nmethod; }
1437
1438 Method* callee_target() const { return _callee_target; }
1439 void set_callee_target (Method* x) { _callee_target = x; }
1440
1441 // Oop results of vm runtime calls
1442 oop vm_result() const { return _vm_result; }
1443 void set_vm_result (oop x) { _vm_result = x; }
1444
1445 Metadata* vm_result_2() const { return _vm_result_2; }
1446 void set_vm_result_2 (Metadata* x) { _vm_result_2 = x; }
1447
1448 MemRegion deferred_card_mark() const { return _deferred_card_mark; }
1449 void set_deferred_card_mark(MemRegion mr) { _deferred_card_mark = mr; }
1450
1451 #if INCLUDE_JVMCI
1452 int pending_deoptimization() const { return _pending_deoptimization; }
1453 oop pending_failed_speculation() const { return _pending_failed_speculation; }
1454 bool adjusting_comp_level() const { return _adjusting_comp_level; }
1455 void set_adjusting_comp_level(bool b) { _adjusting_comp_level = b; }
1456 bool has_pending_monitorenter() const { return _pending_monitorenter; }
1457 void set_pending_monitorenter(bool b) { _pending_monitorenter = b; }
1458 void set_pending_deoptimization(int reason) { _pending_deoptimization = reason; }
1459 void set_pending_failed_speculation(oop failed_speculation) { _pending_failed_speculation = failed_speculation; }
1460 void set_pending_transfer_to_interpreter(bool b) { _pending_transfer_to_interpreter = b; }
1461 void set_jvmci_alternate_call_target(address a) { assert(_jvmci._alternate_call_target == NULL, "must be"); _jvmci._alternate_call_target = a; }
1462 void set_jvmci_implicit_exception_pc(address a) { assert(_jvmci._implicit_exception_pc == NULL, "must be"); _jvmci._implicit_exception_pc = a; }
1463 #endif // INCLUDE_JVMCI
1464
1465 // Exception handling for compiled methods
1466 oop exception_oop() const { return _exception_oop; }
1467 address exception_pc() const { return _exception_pc; }
1468 address exception_handler_pc() const { return _exception_handler_pc; }
1469 bool is_method_handle_return() const { return _is_method_handle_return == 1; }
1470
1471 void set_exception_oop(oop o) { (void)const_cast<oop&>(_exception_oop = o); }
1472 void set_exception_pc(address a) { _exception_pc = a; }
1473 void set_exception_handler_pc(address a) { _exception_handler_pc = a; }
1474 void set_is_method_handle_return(bool value) { _is_method_handle_return = value ? 1 : 0; }
1475
1476 void clear_exception_oop_and_pc() {
1477 set_exception_oop(NULL);
1478 set_exception_pc(NULL);
1479 }
1480
1481 // Stack overflow support
1482 //
1483 // (small addresses)
1484 //
1485 // -- <-- stack_end() ---
1486 // | |
1487 // | red pages |
1488 // | |
1489 // -- <-- stack_red_zone_base() |
1490 // | |
1491 // | guard
1492 // | yellow pages zone
1493 // | |
1494 // | |
1495 // -- <-- stack_yellow_zone_base() |
1496 // | |
1497 // | |
1498 // | reserved pages |
1499 // | |
1500 // -- <-- stack_reserved_zone_base() --- ---
1501 // /|\ shadow <-- stack_overflow_limit() (somewhere in here)
1502 // | zone
1503 // \|/ size
1504 // some untouched memory ---
1505 //
1506 //
1507 // --
1508 // |
1509 // | shadow zone
1510 // |
1511 // --
1512 // x frame n
1513 // --
1514 // x frame n-1
1515 // x
1516 // --
1517 // ...
1518 //
1519 // --
1520 // x frame 0
1521 // -- <-- stack_base()
1522 //
1523 // (large addresses)
1524 //
1525
1526 private:
1527 // These values are derived from flags StackRedPages, StackYellowPages,
1528 // StackReservedPages and StackShadowPages. The zone size is determined
1529 // ergonomically if page_size > 4K.
1530 static size_t _stack_red_zone_size;
1531 static size_t _stack_yellow_zone_size;
1532 static size_t _stack_reserved_zone_size;
1533 static size_t _stack_shadow_zone_size;
1534 public:
1535 inline size_t stack_available(address cur_sp);
1536
1537 static size_t stack_red_zone_size() {
1538 assert(_stack_red_zone_size > 0, "Don't call this before the field is initialized.");
1539 return _stack_red_zone_size;
1540 }
1541 static void set_stack_red_zone_size(size_t s) {
1542 assert(is_aligned(s, os::vm_page_size()),
1543 "We can not protect if the red zone size is not page aligned.");
1544 assert(_stack_red_zone_size == 0, "This should be called only once.");
1545 _stack_red_zone_size = s;
1546 }
1547 address stack_red_zone_base() {
1548 return (address)(stack_end() + stack_red_zone_size());
1549 }
1550 bool in_stack_red_zone(address a) {
1551 return a <= stack_red_zone_base() && a >= stack_end();
1552 }
1553
1554 static size_t stack_yellow_zone_size() {
1555 assert(_stack_yellow_zone_size > 0, "Don't call this before the field is initialized.");
1556 return _stack_yellow_zone_size;
1557 }
1558 static void set_stack_yellow_zone_size(size_t s) {
1559 assert(is_aligned(s, os::vm_page_size()),
1560 "We can not protect if the yellow zone size is not page aligned.");
1561 assert(_stack_yellow_zone_size == 0, "This should be called only once.");
1562 _stack_yellow_zone_size = s;
1563 }
1564
1565 static size_t stack_reserved_zone_size() {
1566 // _stack_reserved_zone_size may be 0. This indicates the feature is off.
1567 return _stack_reserved_zone_size;
1568 }
1569 static void set_stack_reserved_zone_size(size_t s) {
1570 assert(is_aligned(s, os::vm_page_size()),
1571 "We can not protect if the reserved zone size is not page aligned.");
1572 assert(_stack_reserved_zone_size == 0, "This should be called only once.");
1573 _stack_reserved_zone_size = s;
1574 }
1575 address stack_reserved_zone_base() {
1576 return (address)(stack_end() +
1577 (stack_red_zone_size() + stack_yellow_zone_size() + stack_reserved_zone_size()));
1578 }
1579 bool in_stack_reserved_zone(address a) {
1580 return (a <= stack_reserved_zone_base()) &&
1581 (a >= (address)((intptr_t)stack_reserved_zone_base() - stack_reserved_zone_size()));
1582 }
1583
1584 static size_t stack_yellow_reserved_zone_size() {
1585 return _stack_yellow_zone_size + _stack_reserved_zone_size;
1586 }
1587 bool in_stack_yellow_reserved_zone(address a) {
1588 return (a <= stack_reserved_zone_base()) && (a >= stack_red_zone_base());
1589 }
1590
1591 // Size of red + yellow + reserved zones.
1592 static size_t stack_guard_zone_size() {
1593 return stack_red_zone_size() + stack_yellow_reserved_zone_size();
1594 }
1595
1596 static size_t stack_shadow_zone_size() {
1597 assert(_stack_shadow_zone_size > 0, "Don't call this before the field is initialized.");
1598 return _stack_shadow_zone_size;
1599 }
1600 static void set_stack_shadow_zone_size(size_t s) {
1601 // The shadow area is not allocated or protected, so
1602 // it needs not be page aligned.
1603 // But the stack bang currently assumes that it is a
1604 // multiple of page size. This guarantees that the bang
1605 // loop touches all pages in the shadow zone.
1606 // This can be guaranteed differently, as well. E.g., if
1607 // the page size is a multiple of 4K, banging in 4K steps
1608 // suffices to touch all pages. (Some pages are banged
1609 // several times, though.)
1610 assert(is_aligned(s, os::vm_page_size()),
1611 "Stack bang assumes multiple of page size.");
1612 assert(_stack_shadow_zone_size == 0, "This should be called only once.");
1613 _stack_shadow_zone_size = s;
1614 }
1615
1616 void create_stack_guard_pages();
1617 void remove_stack_guard_pages();
1618
1619 void enable_stack_reserved_zone();
1620 void disable_stack_reserved_zone();
1621 void enable_stack_yellow_reserved_zone();
1622 void disable_stack_yellow_reserved_zone();
1623 void enable_stack_red_zone();
1624 void disable_stack_red_zone();
1625
1626 inline bool stack_guard_zone_unused();
1627 inline bool stack_yellow_reserved_zone_disabled();
1628 inline bool stack_reserved_zone_disabled();
1629 inline bool stack_guards_enabled();
1630
1631 address reserved_stack_activation() const { return _reserved_stack_activation; }
1632 void set_reserved_stack_activation(address addr) {
1633 assert(_reserved_stack_activation == stack_base()
1634 || _reserved_stack_activation == NULL
1635 || addr == stack_base(), "Must not be set twice");
1636 _reserved_stack_activation = addr;
1637 }
1638
1639 // Attempt to reguard the stack after a stack overflow may have occurred.
1640 // Returns true if (a) guard pages are not needed on this thread, (b) the
1641 // pages are already guarded, or (c) the pages were successfully reguarded.
1642 // Returns false if there is not enough stack space to reguard the pages, in
1643 // which case the caller should unwind a frame and try again. The argument
1644 // should be the caller's (approximate) sp.
1645 bool reguard_stack(address cur_sp);
1646 // Similar to above but see if current stackpoint is out of the guard area
1647 // and reguard if possible.
1648 bool reguard_stack(void);
1649
1650 address stack_overflow_limit() { return _stack_overflow_limit; }
1651 void set_stack_overflow_limit() {
1652 _stack_overflow_limit =
1653 stack_end() + MAX2(JavaThread::stack_guard_zone_size(), JavaThread::stack_shadow_zone_size());
1654 }
1655
1656 // Misc. accessors/mutators
1657 void set_do_not_unlock(void) { _do_not_unlock_if_synchronized = true; }
1658 void clr_do_not_unlock(void) { _do_not_unlock_if_synchronized = false; }
1659 bool do_not_unlock(void) { return _do_not_unlock_if_synchronized; }
1660
1661 #ifndef PRODUCT
1662 void record_jump(address target, address instr, const char* file, int line);
1663 #endif // PRODUCT
1664
1665 // For assembly stub generation
1666 static ByteSize threadObj_offset() { return byte_offset_of(JavaThread, _threadObj); }
1667 #ifndef PRODUCT
1668 static ByteSize jmp_ring_index_offset() { return byte_offset_of(JavaThread, _jmp_ring_index); }
1669 static ByteSize jmp_ring_offset() { return byte_offset_of(JavaThread, _jmp_ring); }
1670 #endif // PRODUCT
1671 static ByteSize jni_environment_offset() { return byte_offset_of(JavaThread, _jni_environment); }
1672 static ByteSize pending_jni_exception_check_fn_offset() {
1673 return byte_offset_of(JavaThread, _pending_jni_exception_check_fn);
1674 }
1675 static ByteSize last_Java_sp_offset() {
1676 return byte_offset_of(JavaThread, _anchor) + JavaFrameAnchor::last_Java_sp_offset();
1677 }
1678 static ByteSize last_Java_pc_offset() {
1679 return byte_offset_of(JavaThread, _anchor) + JavaFrameAnchor::last_Java_pc_offset();
1680 }
1681 static ByteSize frame_anchor_offset() {
1682 return byte_offset_of(JavaThread, _anchor);
1683 }
1684 static ByteSize callee_target_offset() { return byte_offset_of(JavaThread, _callee_target); }
1685 static ByteSize vm_result_offset() { return byte_offset_of(JavaThread, _vm_result); }
1686 static ByteSize vm_result_2_offset() { return byte_offset_of(JavaThread, _vm_result_2); }
1687 static ByteSize thread_state_offset() { return byte_offset_of(JavaThread, _thread_state); }
1688 static ByteSize saved_exception_pc_offset() { return byte_offset_of(JavaThread, _saved_exception_pc); }
1689 static ByteSize osthread_offset() { return byte_offset_of(JavaThread, _osthread); }
1690 #if INCLUDE_JVMCI
1691 static ByteSize pending_deoptimization_offset() { return byte_offset_of(JavaThread, _pending_deoptimization); }
1692 static ByteSize pending_monitorenter_offset() { return byte_offset_of(JavaThread, _pending_monitorenter); }
1693 static ByteSize pending_failed_speculation_offset() { return byte_offset_of(JavaThread, _pending_failed_speculation); }
1694 static ByteSize jvmci_alternate_call_target_offset() { return byte_offset_of(JavaThread, _jvmci._alternate_call_target); }
1695 static ByteSize jvmci_implicit_exception_pc_offset() { return byte_offset_of(JavaThread, _jvmci._implicit_exception_pc); }
1696 static ByteSize jvmci_counters_offset() { return byte_offset_of(JavaThread, _jvmci_counters); }
1697 #endif // INCLUDE_JVMCI
1698 static ByteSize exception_oop_offset() { return byte_offset_of(JavaThread, _exception_oop); }
1699 static ByteSize exception_pc_offset() { return byte_offset_of(JavaThread, _exception_pc); }
1700 static ByteSize exception_handler_pc_offset() { return byte_offset_of(JavaThread, _exception_handler_pc); }
1701 static ByteSize stack_overflow_limit_offset() { return byte_offset_of(JavaThread, _stack_overflow_limit); }
1702 static ByteSize is_method_handle_return_offset() { return byte_offset_of(JavaThread, _is_method_handle_return); }
1703 static ByteSize stack_guard_state_offset() { return byte_offset_of(JavaThread, _stack_guard_state); }
1704 static ByteSize reserved_stack_activation_offset() { return byte_offset_of(JavaThread, _reserved_stack_activation); }
1705 static ByteSize suspend_flags_offset() { return byte_offset_of(JavaThread, _suspend_flags); }
1706
1707 static ByteSize do_not_unlock_if_synchronized_offset() { return byte_offset_of(JavaThread, _do_not_unlock_if_synchronized); }
1708 static ByteSize should_post_on_exceptions_flag_offset() {
1709 return byte_offset_of(JavaThread, _should_post_on_exceptions_flag);
1710 }
1711
1712 #if INCLUDE_ALL_GCS
1713 static ByteSize satb_mark_queue_offset() { return byte_offset_of(JavaThread, _satb_mark_queue); }
1714 static ByteSize dirty_card_queue_offset() { return byte_offset_of(JavaThread, _dirty_card_queue); }
1715
1716 static ByteSize gc_state_offset() { return byte_offset_of(JavaThread, _gc_state); }
1717
1718 #endif // INCLUDE_ALL_GCS
1719
1720 // Returns the jni environment for this thread
1721 JNIEnv* jni_environment() { return &_jni_environment; }
1722
1723 static JavaThread* thread_from_jni_environment(JNIEnv* env) {
1724 JavaThread *thread_from_jni_env = (JavaThread*)((intptr_t)env - in_bytes(jni_environment_offset()));
1725 // Only return NULL if thread is off the thread list; starting to
1726 // exit should not return NULL.
1727 if (thread_from_jni_env->is_terminated()) {
1728 thread_from_jni_env->block_if_vm_exited();
1729 return NULL;
1730 } else {
1731 return thread_from_jni_env;
1732 }
1733 }
1734
1735 // JNI critical regions. These can nest.
1736 bool in_critical() { return _jni_active_critical > 0; }
1737 bool in_last_critical() { return _jni_active_critical == 1; }
1738 void enter_critical() {
1739 assert(Thread::current() == this ||
1740 (Thread::current()->is_VM_thread() &&
1741 SafepointSynchronize::is_synchronizing()),
1742 "this must be current thread or synchronizing");
1743 _jni_active_critical++;
1744 }
1745 void exit_critical() {
1746 assert(Thread::current() == this, "this must be current thread");
1747 _jni_active_critical--;
1748 assert(_jni_active_critical >= 0, "JNI critical nesting problem?");
1749 }
1750
1751 // Checked JNI: is the programmer required to check for exceptions, if so specify
1752 // which function name. Returning to a Java frame should implicitly clear the
1753 // pending check, this is done for Native->Java transitions (i.e. user JNI code).
1754 // VM->Java transistions are not cleared, it is expected that JNI code enclosed
1755 // within ThreadToNativeFromVM makes proper exception checks (i.e. VM internal).
1756 bool is_pending_jni_exception_check() const { return _pending_jni_exception_check_fn != NULL; }
1757 void clear_pending_jni_exception_check() { _pending_jni_exception_check_fn = NULL; }
1758 const char* get_pending_jni_exception_check() const { return _pending_jni_exception_check_fn; }
1759 void set_pending_jni_exception_check(const char* fn_name) { _pending_jni_exception_check_fn = (char*) fn_name; }
1760
1761 // For deadlock detection
1762 int depth_first_number() { return _depth_first_number; }
1763 void set_depth_first_number(int dfn) { _depth_first_number = dfn; }
1764
1765 private:
1766 void set_monitor_chunks(MonitorChunk* monitor_chunks) { _monitor_chunks = monitor_chunks; }
1767
1768 public:
1769 MonitorChunk* monitor_chunks() const { return _monitor_chunks; }
1770 void add_monitor_chunk(MonitorChunk* chunk);
1771 void remove_monitor_chunk(MonitorChunk* chunk);
1772 bool in_deopt_handler() const { return _in_deopt_handler > 0; }
1773 void inc_in_deopt_handler() { _in_deopt_handler++; }
1774 void dec_in_deopt_handler() {
1775 assert(_in_deopt_handler > 0, "mismatched deopt nesting");
1776 if (_in_deopt_handler > 0) { // robustness
1777 _in_deopt_handler--;
1778 }
1779 }
1780
1781 private:
1782 void set_entry_point(ThreadFunction entry_point) { _entry_point = entry_point; }
1783
1784 public:
1785
1786 // Frame iteration; calls the function f for all frames on the stack
1787 void frames_do(void f(frame*, const RegisterMap*));
1788
1789 // Memory operations
1790 void oops_do(OopClosure* f, CodeBlobClosure* cf);
1791
1792 // Sweeper operations
1793 virtual void nmethods_do(CodeBlobClosure* cf);
1794
1795 // RedefineClasses Support
1796 void metadata_do(void f(Metadata*));
1797
1798 // Misc. operations
1799 char* name() const { return (char*)get_thread_name(); }
1800 void print_on(outputStream* st) const;
1801 void print_value();
1802 void print_thread_state_on(outputStream*) const PRODUCT_RETURN;
1803 void print_thread_state() const PRODUCT_RETURN;
1804 void print_on_error(outputStream* st, char* buf, int buflen) const;
1805 void print_name_on_error(outputStream* st, char* buf, int buflen) const;
1806 void verify();
1807 const char* get_thread_name() const;
1808 private:
1809 // factor out low-level mechanics for use in both normal and error cases
1810 const char* get_thread_name_string(char* buf = NULL, int buflen = 0) const;
1811 public:
1812 const char* get_threadgroup_name() const;
1813 const char* get_parent_name() const;
1814
1815 // Accessing frames
1816 frame last_frame() {
1817 _anchor.make_walkable(this);
1818 return pd_last_frame();
1819 }
1820 javaVFrame* last_java_vframe(RegisterMap* reg_map);
1821
1822 // Returns method at 'depth' java or native frames down the stack
1823 // Used for security checks
1824 Klass* security_get_caller_class(int depth);
1825
1826 // Print stack trace in external format
1827 void print_stack_on(outputStream* st);
1828 void print_stack() { print_stack_on(tty); }
1829
1830 // Print stack traces in various internal formats
1831 void trace_stack() PRODUCT_RETURN;
1832 void trace_stack_from(vframe* start_vf) PRODUCT_RETURN;
1833 void trace_frames() PRODUCT_RETURN;
1834 void trace_oops() PRODUCT_RETURN;
1835
1836 // Print an annotated view of the stack frames
1837 void print_frame_layout(int depth = 0, bool validate_only = false) NOT_DEBUG_RETURN;
1838 void validate_frame_layout() {
1839 print_frame_layout(0, true);
1840 }
1841
1842 // Returns the number of stack frames on the stack
1843 int depth() const;
1844
1845 // Function for testing deoptimization
1846 void deoptimize();
1847 void make_zombies();
1848
1849 void deoptimized_wrt_marked_nmethods();
1850
1851 public:
1852 // Returns the running thread as a JavaThread
1853 static inline JavaThread* current();
1854
1855 // Returns the active Java thread. Do not use this if you know you are calling
1856 // from a JavaThread, as it's slower than JavaThread::current. If called from
1857 // the VMThread, it also returns the JavaThread that instigated the VMThread's
1858 // operation. You may not want that either.
1859 static JavaThread* active();
1860
1861 inline CompilerThread* as_CompilerThread();
1862
1863 public:
1864 virtual void run();
1865 void thread_main_inner();
1866
1867 private:
1868 // PRIVILEGED STACK
1869 PrivilegedElement* _privileged_stack_top;
1870 GrowableArray<oop>* _array_for_gc;
1871 public:
1872
1873 // Returns the privileged_stack information.
1874 PrivilegedElement* privileged_stack_top() const { return _privileged_stack_top; }
1875 void set_privileged_stack_top(PrivilegedElement *e) { _privileged_stack_top = e; }
1876 void register_array_for_gc(GrowableArray<oop>* array) { _array_for_gc = array; }
1877
1878 public:
1879 // Thread local information maintained by JVMTI.
1880 void set_jvmti_thread_state(JvmtiThreadState *value) { _jvmti_thread_state = value; }
1881 // A JvmtiThreadState is lazily allocated. This jvmti_thread_state()
1882 // getter is used to get this JavaThread's JvmtiThreadState if it has
1883 // one which means NULL can be returned. JvmtiThreadState::state_for()
1884 // is used to get the specified JavaThread's JvmtiThreadState if it has
1885 // one or it allocates a new JvmtiThreadState for the JavaThread and
1886 // returns it. JvmtiThreadState::state_for() will return NULL only if
1887 // the specified JavaThread is exiting.
1888 JvmtiThreadState *jvmti_thread_state() const { return _jvmti_thread_state; }
1889 static ByteSize jvmti_thread_state_offset() { return byte_offset_of(JavaThread, _jvmti_thread_state); }
1890 void set_jvmti_get_loaded_classes_closure(JvmtiGetLoadedClassesClosure* value) { _jvmti_get_loaded_classes_closure = value; }
1891 JvmtiGetLoadedClassesClosure* get_jvmti_get_loaded_classes_closure() const { return _jvmti_get_loaded_classes_closure; }
1892
1893 // JVMTI PopFrame support
1894 // Setting and clearing popframe_condition
1895 // All of these enumerated values are bits. popframe_pending
1896 // indicates that a PopFrame() has been requested and not yet been
1897 // completed. popframe_processing indicates that that PopFrame() is in
1898 // the process of being completed. popframe_force_deopt_reexecution_bit
1899 // indicates that special handling is required when returning to a
1900 // deoptimized caller.
1901 enum PopCondition {
1902 popframe_inactive = 0x00,
1903 popframe_pending_bit = 0x01,
1904 popframe_processing_bit = 0x02,
1905 popframe_force_deopt_reexecution_bit = 0x04
1906 };
1907 PopCondition popframe_condition() { return (PopCondition) _popframe_condition; }
1908 void set_popframe_condition(PopCondition c) { _popframe_condition = c; }
1909 void set_popframe_condition_bit(PopCondition c) { _popframe_condition |= c; }
1910 void clear_popframe_condition() { _popframe_condition = popframe_inactive; }
1911 static ByteSize popframe_condition_offset() { return byte_offset_of(JavaThread, _popframe_condition); }
1912 bool has_pending_popframe() { return (popframe_condition() & popframe_pending_bit) != 0; }
1913 bool popframe_forcing_deopt_reexecution() { return (popframe_condition() & popframe_force_deopt_reexecution_bit) != 0; }
1914 void clear_popframe_forcing_deopt_reexecution() { _popframe_condition &= ~popframe_force_deopt_reexecution_bit; }
1915 #ifdef CC_INTERP
1916 bool pop_frame_pending(void) { return ((_popframe_condition & popframe_pending_bit) != 0); }
1917 void clr_pop_frame_pending(void) { _popframe_condition = popframe_inactive; }
1918 bool pop_frame_in_process(void) { return ((_popframe_condition & popframe_processing_bit) != 0); }
1919 void set_pop_frame_in_process(void) { _popframe_condition |= popframe_processing_bit; }
1920 void clr_pop_frame_in_process(void) { _popframe_condition &= ~popframe_processing_bit; }
1921 #endif
1922
1923 int frames_to_pop_failed_realloc() const { return _frames_to_pop_failed_realloc; }
1924 void set_frames_to_pop_failed_realloc(int nb) { _frames_to_pop_failed_realloc = nb; }
1925 void dec_frames_to_pop_failed_realloc() { _frames_to_pop_failed_realloc--; }
1926
1927 private:
1928 // Saved incoming arguments to popped frame.
1929 // Used only when popped interpreted frame returns to deoptimized frame.
1930 void* _popframe_preserved_args;
1931 int _popframe_preserved_args_size;
1932
1933 public:
1934 void popframe_preserve_args(ByteSize size_in_bytes, void* start);
1935 void* popframe_preserved_args();
1936 ByteSize popframe_preserved_args_size();
1937 WordSize popframe_preserved_args_size_in_words();
1938 void popframe_free_preserved_args();
1939
1940
1941 private:
1942 JvmtiThreadState *_jvmti_thread_state;
1943 JvmtiGetLoadedClassesClosure* _jvmti_get_loaded_classes_closure;
1944
1945 // Used by the interpreter in fullspeed mode for frame pop, method
1946 // entry, method exit and single stepping support. This field is
1947 // only set to non-zero by the VM_EnterInterpOnlyMode VM operation.
1948 // It can be set to zero asynchronously (i.e., without a VM operation
1949 // or a lock) so we have to be very careful.
1950 int _interp_only_mode;
1951
1952 public:
1953 // used by the interpreter for fullspeed debugging support (see above)
1954 static ByteSize interp_only_mode_offset() { return byte_offset_of(JavaThread, _interp_only_mode); }
1955 bool is_interp_only_mode() { return (_interp_only_mode != 0); }
1956 int get_interp_only_mode() { return _interp_only_mode; }
1957 void increment_interp_only_mode() { ++_interp_only_mode; }
1958 void decrement_interp_only_mode() { --_interp_only_mode; }
1959
1960 // support for cached flag that indicates whether exceptions need to be posted for this thread
1961 // if this is false, we can avoid deoptimizing when events are thrown
1962 // this gets set to reflect whether jvmtiExport::post_exception_throw would actually do anything
1963 private:
1964 int _should_post_on_exceptions_flag;
1965
1966 public:
1967 int should_post_on_exceptions_flag() { return _should_post_on_exceptions_flag; }
1968 void set_should_post_on_exceptions_flag(int val) { _should_post_on_exceptions_flag = val; }
1969
1970 private:
1971 ThreadStatistics *_thread_stat;
1972
1973 public:
1974 ThreadStatistics* get_thread_stat() const { return _thread_stat; }
1975
1976 // Return a blocker object for which this thread is blocked parking.
1977 oop current_park_blocker();
1978
1979 private:
1980 static size_t _stack_size_at_create;
1981
1982 public:
1983 static inline size_t stack_size_at_create(void) {
1984 return _stack_size_at_create;
1985 }
1986 static inline void set_stack_size_at_create(size_t value) {
1987 _stack_size_at_create = value;
1988 }
1989
1990 #if INCLUDE_ALL_GCS
1991 // SATB marking queue support
1992 SATBMarkQueue& satb_mark_queue() { return _satb_mark_queue; }
1993 static SATBMarkQueueSet& satb_mark_queue_set() {
1994 return _satb_mark_queue_set;
1995 }
1996
1997 // Dirty card queue support
1998 DirtyCardQueue& dirty_card_queue() { return _dirty_card_queue; }
1999 static DirtyCardQueueSet& dirty_card_queue_set() {
2000 return _dirty_card_queue_set;
2001 }
2002
2003 inline char gc_state() const;
2004
2005 private:
2006 void set_gc_state(char in_prog);
2007
2008 public:
2009 static void set_gc_state_all_threads(char in_prog);
2010
2011 #endif // INCLUDE_ALL_GCS
2012
2013 // This method initializes the SATB and dirty card queues before a
2014 // JavaThread is added to the Java thread list. Right now, we don't
2015 // have to do anything to the dirty card queue (it should have been
2016 // activated when the thread was created), but we have to activate
2017 // the SATB queue if the thread is created while a marking cycle is
2018 // in progress. The activation / de-activation of the SATB queues at
2019 // the beginning / end of a marking cycle is done during safepoints
2020 // so we have to make sure this method is called outside one to be
2021 // able to safely read the active field of the SATB queue set. Right
2022 // now, it is called just before the thread is added to the Java
2023 // thread list in the Threads::add() method. That method is holding
2024 // the Threads_lock which ensures we are outside a safepoint. We
2025 // cannot do the obvious and set the active field of the SATB queue
2026 // when the thread is created given that, in some cases, safepoints
2027 // might happen between the JavaThread constructor being called and the
2028 // thread being added to the Java thread list (an example of this is
2029 // when the structure for the DestroyJavaVM thread is created).
2030 #if INCLUDE_ALL_GCS
2031 void initialize_queues();
2032 #else // INCLUDE_ALL_GCS
2033 void initialize_queues() { }
2034 #endif // INCLUDE_ALL_GCS
2035
2036 // Machine dependent stuff
2037 #include OS_CPU_HEADER(thread)
2038
2039 public:
2040 void set_blocked_on_compilation(bool value) {
2041 _blocked_on_compilation = value;
2042 }
2043
2044 bool blocked_on_compilation() {
2045 return _blocked_on_compilation;
2046 }
2047 protected:
2048 bool _blocked_on_compilation;
2049
2050
2051 // JSR166 per-thread parker
2052 private:
2053 Parker* _parker;
2054 public:
2055 Parker* parker() { return _parker; }
2056
2057 // Biased locking support
2058 private:
2059 GrowableArray<MonitorInfo*>* _cached_monitor_info;
2060 public:
2061 GrowableArray<MonitorInfo*>* cached_monitor_info() { return _cached_monitor_info; }
2062 void set_cached_monitor_info(GrowableArray<MonitorInfo*>* info) { _cached_monitor_info = info; }
2063
2064 // clearing/querying jni attach status
2065 bool is_attaching_via_jni() const { return _jni_attach_state == _attaching_via_jni; }
2066 bool has_attached_via_jni() const { return is_attaching_via_jni() || _jni_attach_state == _attached_via_jni; }
2067 inline void set_done_attaching_via_jni();
2068 };
2069
2070 // Inline implementation of JavaThread::current
2071 inline JavaThread* JavaThread::current() {
2072 Thread* thread = Thread::current();
2073 assert(thread->is_Java_thread(), "just checking");
2074 return (JavaThread*)thread;
2075 }
2076
2077 inline CompilerThread* JavaThread::as_CompilerThread() {
2078 assert(is_Compiler_thread(), "just checking");
2079 return (CompilerThread*)this;
2080 }
2081
2082 // Dedicated thread to sweep the code cache
2083 class CodeCacheSweeperThread : public JavaThread {
2084 CompiledMethod* _scanned_compiled_method; // nmethod being scanned by the sweeper
2085 public:
2086 CodeCacheSweeperThread();
2087 // Track the nmethod currently being scanned by the sweeper
2088 void set_scanned_compiled_method(CompiledMethod* cm) {
2089 assert(_scanned_compiled_method == NULL || cm == NULL, "should reset to NULL before writing a new value");
2090 _scanned_compiled_method = cm;
2091 }
2092
2093 // Hide sweeper thread from external view.
2094 bool is_hidden_from_external_view() const { return true; }
2095
2096 bool is_Code_cache_sweeper_thread() const { return true; }
2097
2098 // Prevent GC from unloading _scanned_compiled_method
2099 void oops_do(OopClosure* f, CodeBlobClosure* cf);
2100 void nmethods_do(CodeBlobClosure* cf);
2101 };
2102
2103 // A thread used for Compilation.
2104 class CompilerThread : public JavaThread {
2105 friend class VMStructs;
2106 private:
2107 CompilerCounters* _counters;
2108
2109 ciEnv* _env;
2110 CompileLog* _log;
2111 CompileTask* volatile _task; // print_threads_compiling can read this concurrently.
2112 CompileQueue* _queue;
2113 BufferBlob* _buffer_blob;
2114
2115 AbstractCompiler* _compiler;
2116
2117 public:
2118
2119 static CompilerThread* current();
2120
2121 CompilerThread(CompileQueue* queue, CompilerCounters* counters);
2122
2123 bool is_Compiler_thread() const { return true; }
2124
2125 virtual bool can_call_java() const;
2126
2127 // Hide native compiler threads from external view.
2128 bool is_hidden_from_external_view() const { return !can_call_java(); }
2129
2130 void set_compiler(AbstractCompiler* c) { _compiler = c; }
2131 AbstractCompiler* compiler() const { return _compiler; }
2132
2133 CompileQueue* queue() const { return _queue; }
2134 CompilerCounters* counters() const { return _counters; }
2135
2136 // Get/set the thread's compilation environment.
2137 ciEnv* env() { return _env; }
2138 void set_env(ciEnv* env) { _env = env; }
2139
2140 BufferBlob* get_buffer_blob() const { return _buffer_blob; }
2141 void set_buffer_blob(BufferBlob* b) { _buffer_blob = b; }
2142
2143 // Get/set the thread's logging information
2144 CompileLog* log() { return _log; }
2145 void init_log(CompileLog* log) {
2146 // Set once, for good.
2147 assert(_log == NULL, "set only once");
2148 _log = log;
2149 }
2150
2151 #ifndef PRODUCT
2152 private:
2153 IdealGraphPrinter *_ideal_graph_printer;
2154 public:
2155 IdealGraphPrinter *ideal_graph_printer() { return _ideal_graph_printer; }
2156 void set_ideal_graph_printer(IdealGraphPrinter *n) { _ideal_graph_printer = n; }
2157 #endif
2158
2159 // Get/set the thread's current task
2160 CompileTask* task() { return _task; }
2161 void set_task(CompileTask* task) { _task = task; }
2162 };
2163
2164 inline CompilerThread* CompilerThread::current() {
2165 return JavaThread::current()->as_CompilerThread();
2166 }
2167
2168 // The active thread queue. It also keeps track of the current used
2169 // thread priorities.
2170 class Threads: AllStatic {
2171 friend class VMStructs;
2172 private:
2173 static JavaThread* _thread_list;
2174 static int _number_of_threads;
2175 static int _number_of_non_daemon_threads;
2176 static int _return_code;
2177 static int _thread_claim_parity;
2178 #ifdef ASSERT
2179 static bool _vm_complete;
2180 #endif
2181
2182 static void initialize_java_lang_classes(JavaThread* main_thread, TRAPS);
2183 static void initialize_jsr292_core_classes(TRAPS);
2184
2185 public:
2186 // Thread management
2187 // force_daemon is a concession to JNI, where we may need to add a
2188 // thread to the thread list before allocating its thread object
2189 static void add(JavaThread* p, bool force_daemon = false);
2190 static void remove(JavaThread* p);
2191 static void threads_do(ThreadClosure* tc);
2192 static void java_threads_do(ThreadClosure* tc);
2193 static void possibly_parallel_threads_do(bool is_par, ThreadClosure* tc);
2194
2195 // Initializes the vm and creates the vm thread
2196 static jint create_vm(JavaVMInitArgs* args, bool* canTryAgain);
2197 static void convert_vm_init_libraries_to_agents();
2198 static void create_vm_init_libraries();
2199 static void create_vm_init_agents();
2200 static void shutdown_vm_agents();
2201 static bool destroy_vm();
2202 // Supported VM versions via JNI
2203 // Includes JNI_VERSION_1_1
2204 static jboolean is_supported_jni_version_including_1_1(jint version);
2205 // Does not include JNI_VERSION_1_1
2206 static jboolean is_supported_jni_version(jint version);
2207
2208 // The "thread claim parity" provides a way for threads to be claimed
2209 // by parallel worker tasks.
2210 //
2211 // Each thread contains a a "parity" field. A task will claim the
2212 // thread only if its parity field is the same as the global parity,
2213 // which is updated by calling change_thread_claim_parity().
2214 //
2215 // For this to work change_thread_claim_parity() needs to be called
2216 // exactly once in sequential code before starting parallel tasks
2217 // that should claim threads.
2218 //
2219 // New threads get their parity set to 0 and change_thread_claim_parity()
2220 // never set the global parity to 0.
2221 static int thread_claim_parity() { return _thread_claim_parity; }
2222 static void change_thread_claim_parity();
2223 static void assert_all_threads_claimed() NOT_DEBUG_RETURN;
2224
2225 // Apply "f->do_oop" to all root oops in all threads.
2226 // This version may only be called by sequential code.
2227 static void oops_do(OopClosure* f, CodeBlobClosure* cf);
2228 // This version may be called by sequential or parallel code.
2229 static void possibly_parallel_oops_do(bool is_par, OopClosure* f, CodeBlobClosure* cf, CodeBlobClosure* nmethods_cl = NULL, ThreadClosure* thread_cl = NULL);
2230 // This creates a list of GCTasks, one per thread.
2231 static void create_thread_roots_tasks(GCTaskQueue* q);
2232 // This creates a list of GCTasks, one per thread, for marking objects.
2233 static void create_thread_roots_marking_tasks(GCTaskQueue* q);
2234
2235 // Apply "f->do_oop" to roots in all threads that
2236 // are part of compiled frames
2237 static void compiled_frame_oops_do(OopClosure* f, CodeBlobClosure* cf);
2238
2239 static void convert_hcode_pointers();
2240 static void restore_hcode_pointers();
2241
2242 // Sweeper
2243 static void nmethods_do(CodeBlobClosure* cf);
2244
2245 // RedefineClasses support
2246 static void metadata_do(void f(Metadata*));
2247 static void metadata_handles_do(void f(Metadata*));
2248
2249 #ifdef ASSERT
2250 static bool is_vm_complete() { return _vm_complete; }
2251 #endif
2252
2253 // Verification
2254 static void verify();
2255 static void print_on(outputStream* st, bool print_stacks, bool internal_format, bool print_concurrent_locks);
2256 static void print(bool print_stacks, bool internal_format) {
2257 // this function is only used by debug.cpp
2258 print_on(tty, print_stacks, internal_format, false /* no concurrent lock printed */);
2259 }
2260 static void print_on_error(outputStream* st, Thread* current, char* buf, int buflen);
2261 static void print_on_error(Thread* this_thread, outputStream* st, Thread* current, char* buf,
2262 int buflen, bool* found_current);
2263 static void print_threads_compiling(outputStream* st, char* buf, int buflen);
2264
2265 // Get Java threads that are waiting to enter a monitor.
2266 static GrowableArray<JavaThread*>* get_pending_threads(ThreadsList * t_list,
2267 int count, address monitor);
2268
2269 // Get owning Java thread from the monitor's owner field.
2270 static JavaThread *owning_thread_from_monitor_owner(ThreadsList * t_list,
2271 address owner);
2272
2273 // Number of threads on the active threads list
2274 static int number_of_threads() { return _number_of_threads; }
2275 // Number of non-daemon threads on the active threads list
2276 static int number_of_non_daemon_threads() { return _number_of_non_daemon_threads; }
2277
2278 // Deoptimizes all frames tied to marked nmethods
2279 static void deoptimized_wrt_marked_nmethods();
2280 };
2281
2282
2283 // Thread iterator
2284 class ThreadClosure: public StackObj {
2285 public:
2286 virtual void do_thread(Thread* thread) = 0;
2287 };
2288
2289 class SignalHandlerMark: public StackObj {
2290 private:
2291 Thread* _thread;
2292 public:
2293 SignalHandlerMark(Thread* t) {
2294 _thread = t;
2295 if (_thread) _thread->enter_signal_handler();
2296 }
2297 ~SignalHandlerMark() {
2298 if (_thread) _thread->leave_signal_handler();
2299 _thread = NULL;
2300 }
2301 };
2302
2303
2304 #endif // SHARE_VM_RUNTIME_THREAD_HPP