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 #ifdef INCLUDE_ALL_GCS
95 class PLAB;
96 #endif
97
98 // Class hierarchy
99 // - Thread
100 // - NamedThread
101 // - VMThread
102 // - ConcurrentGCThread
103 // - WorkerThread
104 // - GangWorker
105 // - GCTaskThread
106 // - JavaThread
107 // - various subclasses eg CompilerThread, ServiceThread
108 // - WatcherThread
109
110 class Thread: public ThreadShadow {
111 friend class VMStructs;
112 friend class JVMCIVMStructs;
113 private:
114
115 #ifndef USE_LIBRARY_BASED_TLS_ONLY
116 // Current thread is maintained as a thread-local variable
117 static THREAD_LOCAL_DECL Thread* _thr_current;
118 #endif
119
120 // Exception handling
121 // (Note: _pending_exception and friends are in ThreadShadow)
122 //oop _pending_exception; // pending exception for current thread
123 // const char* _exception_file; // file information for exception (debugging only)
124 // int _exception_line; // line information for exception (debugging only)
125 protected:
126 // Support for forcing alignment of thread objects for biased locking
127 void* _real_malloc_address;
128
129 // JavaThread lifecycle support:
130 friend class ScanHazardPtrGatherProtectedThreadsClosure; // for cmpxchg_threads_hazard_ptr(), get_threads_hazard_ptr(), is_hazard_ptr_tagged() access
131 friend class ScanHazardPtrGatherThreadsListClosure; // for get_nested_threads_hazard_ptr(), get_threads_hazard_ptr(), untag_hazard_ptr() access
132 friend class ScanHazardPtrPrintMatchingThreadsClosure; // for get_threads_hazard_ptr(), is_hazard_ptr_tagged() access
133 friend class ThreadsListSetter; // for get_threads_hazard_ptr() access
134 friend class ThreadsSMRSupport; // for get_threads_hazard_ptr() access
135
136 ThreadsList* volatile _threads_hazard_ptr;
137 ThreadsList* cmpxchg_threads_hazard_ptr(ThreadsList* exchange_value, ThreadsList* compare_value);
138 ThreadsList* get_threads_hazard_ptr();
139 void set_threads_hazard_ptr(ThreadsList* new_list);
140 static bool is_hazard_ptr_tagged(ThreadsList* list) {
141 return (intptr_t(list) & intptr_t(1)) == intptr_t(1);
142 }
143 static ThreadsList* tag_hazard_ptr(ThreadsList* list) {
144 return (ThreadsList*)(intptr_t(list) | intptr_t(1));
145 }
146 static ThreadsList* untag_hazard_ptr(ThreadsList* list) {
147 return (ThreadsList*)(intptr_t(list) & ~intptr_t(1));
148 }
149 NestedThreadsList* _nested_threads_hazard_ptr;
150 NestedThreadsList* get_nested_threads_hazard_ptr() {
151 return _nested_threads_hazard_ptr;
152 }
153 void set_nested_threads_hazard_ptr(NestedThreadsList* value) {
154 assert(Threads_lock->owned_by_self(),
155 "must own Threads_lock for _nested_threads_hazard_ptr to be valid.");
156 _nested_threads_hazard_ptr = value;
157 }
158 // This field is enabled via -XX:+EnableThreadSMRStatistics:
159 uint _nested_threads_hazard_ptr_cnt;
160 void dec_nested_threads_hazard_ptr_cnt() {
161 assert(_nested_threads_hazard_ptr_cnt != 0, "mismatched {dec,inc}_nested_threads_hazard_ptr_cnt()");
162 _nested_threads_hazard_ptr_cnt--;
163 }
164 void inc_nested_threads_hazard_ptr_cnt() {
165 _nested_threads_hazard_ptr_cnt++;
166 }
167 uint nested_threads_hazard_ptr_cnt() {
168 return _nested_threads_hazard_ptr_cnt;
169 }
170
171 public:
172 void* operator new(size_t size) throw() { return allocate(size, true); }
173 void* operator new(size_t size, const std::nothrow_t& nothrow_constant) throw() {
174 return allocate(size, false); }
175 void operator delete(void* p);
176
177 protected:
178 static void* allocate(size_t size, bool throw_excpt, MEMFLAGS flags = mtThread);
179 private:
180
181 // ***************************************************************
182 // Suspend and resume support
183 // ***************************************************************
184 //
185 // VM suspend/resume no longer exists - it was once used for various
186 // things including safepoints but was deprecated and finally removed
187 // in Java 7. Because VM suspension was considered "internal" Java-level
188 // suspension was considered "external", and this legacy naming scheme
189 // remains.
190 //
191 // External suspend/resume requests come from JVM_SuspendThread,
192 // JVM_ResumeThread, JVMTI SuspendThread, and finally JVMTI
193 // ResumeThread. External
194 // suspend requests cause _external_suspend to be set and external
195 // resume requests cause _external_suspend to be cleared.
196 // External suspend requests do not nest on top of other external
197 // suspend requests. The higher level APIs reject suspend requests
198 // for already suspended threads.
199 //
200 // The external_suspend
201 // flag is checked by has_special_runtime_exit_condition() and java thread
202 // will self-suspend when handle_special_runtime_exit_condition() is
203 // called. Most uses of the _thread_blocked state in JavaThreads are
204 // considered the same as being externally suspended; if the blocking
205 // condition lifts, the JavaThread will self-suspend. Other places
206 // where VM checks for external_suspend include:
207 // + mutex granting (do not enter monitors when thread is suspended)
208 // + state transitions from _thread_in_native
209 //
210 // In general, java_suspend() does not wait for an external suspend
211 // request to complete. When it returns, the only guarantee is that
212 // the _external_suspend field is true.
213 //
214 // wait_for_ext_suspend_completion() is used to wait for an external
215 // suspend request to complete. External suspend requests are usually
216 // followed by some other interface call that requires the thread to
217 // be quiescent, e.g., GetCallTrace(). By moving the "wait time" into
218 // the interface that requires quiescence, we give the JavaThread a
219 // chance to self-suspend before we need it to be quiescent. This
220 // improves overall suspend/query performance.
221 //
222 // _suspend_flags controls the behavior of java_ suspend/resume.
223 // It must be set under the protection of SR_lock. Read from the flag is
224 // OK without SR_lock as long as the value is only used as a hint.
225 // (e.g., check _external_suspend first without lock and then recheck
226 // inside SR_lock and finish the suspension)
227 //
228 // _suspend_flags is also overloaded for other "special conditions" so
229 // that a single check indicates whether any special action is needed
230 // eg. for async exceptions.
231 // -------------------------------------------------------------------
232 // Notes:
233 // 1. The suspend/resume logic no longer uses ThreadState in OSThread
234 // but we still update its value to keep other part of the system (mainly
235 // JVMTI) happy. ThreadState is legacy code (see notes in
236 // osThread.hpp).
237 //
238 // 2. It would be more natural if set_external_suspend() is private and
239 // part of java_suspend(), but that probably would affect the suspend/query
240 // performance. Need more investigation on this.
241
242 // suspend/resume lock: used for self-suspend
243 Monitor* _SR_lock;
244
245 protected:
246 enum SuspendFlags {
247 // NOTE: avoid using the sign-bit as cc generates different test code
248 // when the sign-bit is used, and sometimes incorrectly - see CR 6398077
249
250 _external_suspend = 0x20000000U, // thread is asked to self suspend
251 _ext_suspended = 0x40000000U, // thread has self-suspended
252 _deopt_suspend = 0x10000000U, // thread needs to self suspend for deopt
253
254 _has_async_exception = 0x00000001U, // there is a pending async exception
255 _critical_native_unlock = 0x00000002U, // Must call back to unlock JNI critical lock
256
257 _trace_flag = 0x00000004U // call tracing backend
258 };
259
260 // various suspension related flags - atomically updated
261 // overloaded for async exception checking in check_special_condition_for_native_trans.
262 volatile uint32_t _suspend_flags;
263
264 private:
265 int _num_nested_signal;
266
267 DEBUG_ONLY(bool _suspendible_thread;)
268
269 public:
270 void enter_signal_handler() { _num_nested_signal++; }
271 void leave_signal_handler() { _num_nested_signal--; }
272 bool is_inside_signal_handler() const { return _num_nested_signal > 0; }
273
274 #ifdef ASSERT
275 void set_suspendible_thread() {
276 _suspendible_thread = true;
277 }
278
279 void clear_suspendible_thread() {
280 _suspendible_thread = false;
281 }
282
283 bool is_suspendible_thread() { return _suspendible_thread; }
284 #endif
285
286 private:
287 // Active_handles points to a block of handles
288 JNIHandleBlock* _active_handles;
289
290 // One-element thread local free list
291 JNIHandleBlock* _free_handle_block;
292
293 // Point to the last handle mark
294 HandleMark* _last_handle_mark;
295
296 // The parity of the last strong_roots iteration in which this thread was
297 // claimed as a task.
298 int _oops_do_parity;
299
300 public:
301 void set_last_handle_mark(HandleMark* mark) { _last_handle_mark = mark; }
302 HandleMark* last_handle_mark() const { return _last_handle_mark; }
303 private:
304
305 // debug support for checking if code does allow safepoints or not
306 // GC points in the VM can happen because of allocation, invoking a VM operation, or blocking on
307 // mutex, or blocking on an object synchronizer (Java locking).
308 // If !allow_safepoint(), then an assertion failure will happen in any of the above cases
309 // If !allow_allocation(), then an assertion failure will happen during allocation
310 // (Hence, !allow_safepoint() => !allow_allocation()).
311 //
312 // The two classes NoSafepointVerifier and No_Allocation_Verifier are used to set these counters.
313 //
314 NOT_PRODUCT(int _allow_safepoint_count;) // If 0, thread allow a safepoint to happen
315 debug_only(int _allow_allocation_count;) // If 0, the thread is allowed to allocate oops.
316
317 // Used by SkipGCALot class.
318 NOT_PRODUCT(bool _skip_gcalot;) // Should we elide gc-a-lot?
319
320 friend class NoAllocVerifier;
321 friend class NoSafepointVerifier;
322 friend class PauseNoSafepointVerifier;
323 friend class GCLocker;
324
325 volatile void* _polling_page; // Thread local polling page
326
327 ThreadLocalAllocBuffer _tlab; // Thread-local eden
328 PLAB* _gclab; // Thread-local allocation buffer for GC (e.g. evacuation)
329 jlong _allocated_bytes; // Cumulative number of bytes allocated on
330 // the Java heap
331 mutable TRACE_DATA _trace_data; // Thread-local data for tracing
332
333 ThreadExt _ext;
334
335 int _vm_operation_started_count; // VM_Operation support
336 int _vm_operation_completed_count; // VM_Operation support
337
338 char _oom_during_evac;
339
340 ObjectMonitor* _current_pending_monitor; // ObjectMonitor this thread
341 // is waiting to lock
342 bool _current_pending_monitor_is_from_java; // locking is from Java code
343
344 // ObjectMonitor on which this thread called Object.wait()
345 ObjectMonitor* _current_waiting_monitor;
346
347 // Private thread-local objectmonitor list - a simple cache organized as a SLL.
348 public:
349 ObjectMonitor* omFreeList;
350 int omFreeCount; // length of omFreeList
351 int omFreeProvision; // reload chunk size
352 ObjectMonitor* omInUseList; // SLL to track monitors in circulation
353 int omInUseCount; // length of omInUseList
354
355 #ifdef ASSERT
356 private:
357 bool _visited_for_critical_count;
358
359 public:
360 void set_visited_for_critical_count(bool z) { _visited_for_critical_count = z; }
361 bool was_visited_for_critical_count() const { return _visited_for_critical_count; }
362 #endif
363
364 public:
365 enum {
366 is_definitely_current_thread = true
367 };
368
369 // Constructor
370 Thread();
371 virtual ~Thread();
372
373 // Manage Thread::current()
374 void initialize_thread_current();
375 void clear_thread_current(); // TLS cleanup needed before threads terminate
376
377 public:
378 // thread entry point
379 virtual void run();
380
381 // Testers
382 virtual bool is_VM_thread() const { return false; }
383 virtual bool is_Java_thread() const { return false; }
384 virtual bool is_Compiler_thread() const { return false; }
385 virtual bool is_Code_cache_sweeper_thread() const { return false; }
386 virtual bool is_hidden_from_external_view() const { return false; }
387 virtual bool is_jvmti_agent_thread() const { return false; }
388 // True iff the thread can perform GC operations at a safepoint.
389 // Generally will be true only of VM thread and parallel GC WorkGang
390 // threads.
391 virtual bool is_GC_task_thread() const { return false; }
392 virtual bool is_Watcher_thread() const { return false; }
393 virtual bool is_ConcurrentGC_thread() const { return false; }
394 virtual bool is_Named_thread() const { return false; }
395 virtual bool is_Worker_thread() const { return false; }
396
397 // Can this thread make Java upcalls
398 virtual bool can_call_java() const { return false; }
399
400 // Casts
401 virtual WorkerThread* as_Worker_thread() const { return NULL; }
402
403 virtual char* name() const { return (char*)"Unknown thread"; }
404
405 // Returns the current thread (ASSERTS if NULL)
406 static inline Thread* current();
407 // Returns the current thread, or NULL if not attached
408 static inline Thread* current_or_null();
409 // Returns the current thread, or NULL if not attached, and is
410 // safe for use from signal-handlers
411 static inline Thread* current_or_null_safe();
412
413 // Common thread operations
414 #ifdef ASSERT
415 static void check_for_dangling_thread_pointer(Thread *thread);
416 #endif
417 static void set_priority(Thread* thread, ThreadPriority priority);
418 static ThreadPriority get_priority(const Thread* const thread);
419 static void start(Thread* thread);
420 static void interrupt(Thread* thr);
421 static bool is_interrupted(Thread* thr, bool clear_interrupted);
422
423 void set_native_thread_name(const char *name) {
424 assert(Thread::current() == this, "set_native_thread_name can only be called on the current thread");
425 os::set_native_thread_name(name);
426 }
427
428 ObjectMonitor** omInUseList_addr() { return (ObjectMonitor **)&omInUseList; }
429 Monitor* SR_lock() const { return _SR_lock; }
430
431 bool has_async_exception() const { return (_suspend_flags & _has_async_exception) != 0; }
432
433 inline void set_suspend_flag(SuspendFlags f);
434 inline void clear_suspend_flag(SuspendFlags f);
435
436 inline void set_has_async_exception();
437 inline void clear_has_async_exception();
438
439 bool do_critical_native_unlock() const { return (_suspend_flags & _critical_native_unlock) != 0; }
440
441 inline void set_critical_native_unlock();
442 inline void clear_critical_native_unlock();
443
444 inline void set_trace_flag();
445 inline void clear_trace_flag();
446
447 bool is_oom_during_evac() const;
448 void set_oom_during_evac(bool oom);
449
450 #ifdef ASSERT
451 bool is_evac_allowed() const;
452 void set_evac_allowed(bool evac_allowed);
453 #endif
454
455 // Support for Unhandled Oop detection
456 // Add the field for both, fastdebug and debug, builds to keep
457 // Thread's fields layout the same.
458 // Note: CHECK_UNHANDLED_OOPS is defined only for fastdebug build.
459 #ifdef CHECK_UNHANDLED_OOPS
460 private:
461 UnhandledOops* _unhandled_oops;
462 #elif defined(ASSERT)
463 private:
464 void* _unhandled_oops;
465 #endif
466 #ifdef CHECK_UNHANDLED_OOPS
467 public:
468 UnhandledOops* unhandled_oops() { return _unhandled_oops; }
469 // Mark oop safe for gc. It may be stack allocated but won't move.
470 void allow_unhandled_oop(oop *op) {
471 if (CheckUnhandledOops) unhandled_oops()->allow_unhandled_oop(op);
472 }
473 // Clear oops at safepoint so crashes point to unhandled oop violator
474 void clear_unhandled_oops() {
475 if (CheckUnhandledOops) unhandled_oops()->clear_unhandled_oops();
476 }
477 #endif // CHECK_UNHANDLED_OOPS
478
479 public:
480 #ifndef PRODUCT
481 bool skip_gcalot() { return _skip_gcalot; }
482 void set_skip_gcalot(bool v) { _skip_gcalot = v; }
483 #endif
484
485 // Installs a pending exception to be inserted later
486 static void send_async_exception(oop thread_oop, oop java_throwable);
487
488 // Resource area
489 ResourceArea* resource_area() const { return _resource_area; }
490 void set_resource_area(ResourceArea* area) { _resource_area = area; }
491
492 OSThread* osthread() const { return _osthread; }
493 void set_osthread(OSThread* thread) { _osthread = thread; }
494
495 // JNI handle support
496 JNIHandleBlock* active_handles() const { return _active_handles; }
497 void set_active_handles(JNIHandleBlock* block) { _active_handles = block; }
498 JNIHandleBlock* free_handle_block() const { return _free_handle_block; }
499 void set_free_handle_block(JNIHandleBlock* block) { _free_handle_block = block; }
500
501 // Internal handle support
502 HandleArea* handle_area() const { return _handle_area; }
503 void set_handle_area(HandleArea* area) { _handle_area = area; }
504
505 GrowableArray<Metadata*>* metadata_handles() const { return _metadata_handles; }
506 void set_metadata_handles(GrowableArray<Metadata*>* handles){ _metadata_handles = handles; }
507
508 // Thread-Local Allocation Buffer (TLAB) support
509 ThreadLocalAllocBuffer& tlab() { return _tlab; }
510 void initialize_tlab() {
511 if (UseTLAB) {
512 tlab().initialize();
513 }
514 }
515
516 // Thread-Local GC Allocation Buffer (GCLAB) support
517 PLAB* gclab() { return _gclab; }
518 void set_gclab(PLAB* gclab) { _gclab = gclab; }
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 TRACE_DEFINE_THREAD_TRACE_DATA_OFFSET;
525 TRACE_DATA* trace_data() const { return &_trace_data; }
526 bool is_trace_suspend() { return (_suspend_flags & _trace_flag) != 0; }
527
528 const ThreadExt& ext() const { return _ext; }
529 ThreadExt& ext() { return _ext; }
530
531 // VM operation support
532 int vm_operation_ticket() { return ++_vm_operation_started_count; }
533 int vm_operation_completed_count() { return _vm_operation_completed_count; }
534 void increment_vm_operation_completed_count() { _vm_operation_completed_count++; }
535
536 // For tracking the heavyweight monitor the thread is pending on.
537 ObjectMonitor* current_pending_monitor() {
538 return _current_pending_monitor;
539 }
540 void set_current_pending_monitor(ObjectMonitor* monitor) {
541 _current_pending_monitor = monitor;
542 }
543 void set_current_pending_monitor_is_from_java(bool from_java) {
544 _current_pending_monitor_is_from_java = from_java;
545 }
546 bool current_pending_monitor_is_from_java() {
547 return _current_pending_monitor_is_from_java;
548 }
549
550 // For tracking the ObjectMonitor on which this thread called Object.wait()
551 ObjectMonitor* current_waiting_monitor() {
552 return _current_waiting_monitor;
553 }
554 void set_current_waiting_monitor(ObjectMonitor* monitor) {
555 _current_waiting_monitor = monitor;
556 }
557
558 // GC support
559 // Apply "f->do_oop" to all root oops in "this".
560 // Used by JavaThread::oops_do.
561 // Apply "cf->do_code_blob" (if !NULL) to all code blobs active in frames
562 virtual void oops_do(OopClosure* f, CodeBlobClosure* cf);
563
564 // Handles the parallel case for the method below.
565 private:
566 bool claim_oops_do_par_case(int collection_parity);
567 public:
568 // Requires that "collection_parity" is that of the current roots
569 // iteration. If "is_par" is false, sets the parity of "this" to
570 // "collection_parity", and returns "true". If "is_par" is true,
571 // uses an atomic instruction to set the current threads parity to
572 // "collection_parity", if it is not already. Returns "true" iff the
573 // calling thread does the update, this indicates that the calling thread
574 // has claimed the thread's stack as a root groop in the current
575 // collection.
576 bool claim_oops_do(bool is_par, int collection_parity) {
577 if (!is_par) {
578 _oops_do_parity = collection_parity;
579 return true;
580 } else {
581 return claim_oops_do_par_case(collection_parity);
582 }
583 }
584
585 // jvmtiRedefineClasses support
586 void metadata_handles_do(void f(Metadata*));
587
588 // Used by fast lock support
589 virtual bool is_lock_owned(address adr) const;
590
591 // Check if address is in the stack of the thread (not just for locks).
592 // Warning: the method can only be used on the running thread
593 bool is_in_stack(address adr) const;
594 // Check if address is in the usable part of the stack (excludes protected
595 // guard pages)
596 bool is_in_usable_stack(address adr) const;
597
598 // Sets this thread as starting thread. Returns failure if thread
599 // creation fails due to lack of memory, too many threads etc.
600 bool set_as_starting_thread();
601
602 protected:
603 // OS data associated with the thread
604 OSThread* _osthread; // Platform-specific thread information
605
606 // Thread local resource area for temporary allocation within the VM
607 ResourceArea* _resource_area;
608
609 DEBUG_ONLY(ResourceMark* _current_resource_mark;)
610
611 // Thread local handle area for allocation of handles within the VM
612 HandleArea* _handle_area;
613 GrowableArray<Metadata*>* _metadata_handles;
614
615 // Support for stack overflow handling, get_thread, etc.
616 address _stack_base;
617 size_t _stack_size;
618 uintptr_t _self_raw_id; // used by get_thread (mutable)
619 int _lgrp_id;
620
621 volatile void** polling_page_addr() { return &_polling_page; }
622
623 public:
624 // Stack overflow support
625 address stack_base() const { assert(_stack_base != NULL,"Sanity check"); return _stack_base; }
626 void set_stack_base(address base) { _stack_base = base; }
627 size_t stack_size() const { return _stack_size; }
628 void set_stack_size(size_t size) { _stack_size = size; }
629 address stack_end() const { return stack_base() - stack_size(); }
630 void record_stack_base_and_size();
631
632 bool on_local_stack(address adr) const {
633 // QQQ this has knowledge of direction, ought to be a stack method
634 return (_stack_base >= adr && adr >= stack_end());
635 }
636
637 uintptr_t self_raw_id() { return _self_raw_id; }
638 void set_self_raw_id(uintptr_t value) { _self_raw_id = value; }
639
640 int lgrp_id() const { return _lgrp_id; }
641 void set_lgrp_id(int value) { _lgrp_id = value; }
642
643 // Printing
644 virtual void print_on(outputStream* st) const;
645 virtual void print_nested_threads_hazard_ptrs_on(outputStream* st) const;
646 void print() const { print_on(tty); }
647 virtual void print_on_error(outputStream* st, char* buf, int buflen) const;
648 void print_value_on(outputStream* st) const;
649
650 // Debug-only code
651 #ifdef ASSERT
652 private:
653 // Deadlock detection support for Mutex locks. List of locks own by thread.
654 Monitor* _owned_locks;
655 // Mutex::set_owner_implementation is the only place where _owned_locks is modified,
656 // thus the friendship
657 friend class Mutex;
658 friend class Monitor;
659
660 public:
661 void print_owned_locks_on(outputStream* st) const;
662 void print_owned_locks() const { print_owned_locks_on(tty); }
663 Monitor* owned_locks() const { return _owned_locks; }
664 bool owns_locks() const { return owned_locks() != NULL; }
665 bool owns_locks_but_compiled_lock() const;
666 int oops_do_parity() const { return _oops_do_parity; }
667
668 // Deadlock detection
669 bool allow_allocation() { return _allow_allocation_count == 0; }
670 ResourceMark* current_resource_mark() { return _current_resource_mark; }
671 void set_current_resource_mark(ResourceMark* rm) { _current_resource_mark = rm; }
672 #endif
673
674 void check_for_valid_safepoint_state(bool potential_vm_operation) PRODUCT_RETURN;
675
676 private:
677 volatile int _jvmti_env_iteration_count;
678
679 public:
680 void entering_jvmti_env_iteration() { ++_jvmti_env_iteration_count; }
681 void leaving_jvmti_env_iteration() { --_jvmti_env_iteration_count; }
682 bool is_inside_jvmti_env_iteration() { return _jvmti_env_iteration_count > 0; }
683
684 // Code generation
685 static ByteSize exception_file_offset() { return byte_offset_of(Thread, _exception_file); }
686 static ByteSize exception_line_offset() { return byte_offset_of(Thread, _exception_line); }
687 static ByteSize active_handles_offset() { return byte_offset_of(Thread, _active_handles); }
688
689 static ByteSize stack_base_offset() { return byte_offset_of(Thread, _stack_base); }
690 static ByteSize stack_size_offset() { return byte_offset_of(Thread, _stack_size); }
691
692 static ByteSize polling_page_offset() { return byte_offset_of(Thread, _polling_page); }
693
694 #define TLAB_FIELD_OFFSET(name) \
695 static ByteSize tlab_##name##_offset() { return byte_offset_of(Thread, _tlab) + ThreadLocalAllocBuffer::name##_offset(); }
696
697 TLAB_FIELD_OFFSET(start)
698 TLAB_FIELD_OFFSET(end)
699 TLAB_FIELD_OFFSET(top)
700 TLAB_FIELD_OFFSET(pf_top)
701 TLAB_FIELD_OFFSET(size) // desired_size
702 TLAB_FIELD_OFFSET(refill_waste_limit)
703 TLAB_FIELD_OFFSET(number_of_refills)
704 TLAB_FIELD_OFFSET(fast_refill_waste)
705 TLAB_FIELD_OFFSET(slow_allocations)
706
707 #undef TLAB_FIELD_OFFSET
708
709 static ByteSize allocated_bytes_offset() { return byte_offset_of(Thread, _allocated_bytes); }
710
711 public:
712 volatile intptr_t _Stalled;
713 volatile int _TypeTag;
714 ParkEvent * _ParkEvent; // for synchronized()
715 ParkEvent * _SleepEvent; // for Thread.sleep
716 ParkEvent * _MutexEvent; // for native internal Mutex/Monitor
717 ParkEvent * _MuxEvent; // for low-level muxAcquire-muxRelease
718 int NativeSyncRecursion; // diagnostic
719
720 volatile int _OnTrap; // Resume-at IP delta
721 jint _hashStateW; // Marsaglia Shift-XOR thread-local RNG
722 jint _hashStateX; // thread-specific hashCode generator state
723 jint _hashStateY;
724 jint _hashStateZ;
725 void * _schedctl;
726
727
728 volatile jint rng[4]; // RNG for spin loop
729
730 // Low-level leaf-lock primitives used to implement synchronization
731 // and native monitor-mutex infrastructure.
732 // Not for general synchronization use.
733 static void SpinAcquire(volatile int * Lock, const char * Name);
734 static void SpinRelease(volatile int * Lock);
735 static void muxAcquire(volatile intptr_t * Lock, const char * Name);
736 static void muxAcquireW(volatile intptr_t * Lock, ParkEvent * ev);
737 static void muxRelease(volatile intptr_t * Lock);
738 };
739
740 // Inline implementation of Thread::current()
741 inline Thread* Thread::current() {
742 Thread* current = current_or_null();
743 assert(current != NULL, "Thread::current() called on detached thread");
744 return current;
745 }
746
747 inline Thread* Thread::current_or_null() {
748 #ifndef USE_LIBRARY_BASED_TLS_ONLY
749 return _thr_current;
750 #else
751 if (ThreadLocalStorage::is_initialized()) {
752 return ThreadLocalStorage::thread();
753 }
754 return NULL;
755 #endif
756 }
757
758 inline Thread* Thread::current_or_null_safe() {
759 if (ThreadLocalStorage::is_initialized()) {
760 return ThreadLocalStorage::thread();
761 }
762 return NULL;
763 }
764
765 // Name support for threads. non-JavaThread subclasses with multiple
766 // uniquely named instances should derive from this.
767 class NamedThread: public Thread {
768 friend class VMStructs;
769 enum {
770 max_name_len = 64
771 };
772 private:
773 char* _name;
774 // log JavaThread being processed by oops_do
775 JavaThread* _processed_thread;
776 uint _gc_id; // The current GC id when a thread takes part in GC
777
778 public:
779 NamedThread();
780 ~NamedThread();
781 // May only be called once per thread.
782 void set_name(const char* format, ...) ATTRIBUTE_PRINTF(2, 3);
783 void initialize_named_thread();
784 virtual bool is_Named_thread() const { return true; }
785 virtual char* name() const { return _name == NULL ? (char*)"Unknown Thread" : _name; }
786 JavaThread *processed_thread() { return _processed_thread; }
787 void set_processed_thread(JavaThread *thread) { _processed_thread = thread; }
788 virtual void print_on(outputStream* st) const;
789
790 void set_gc_id(uint gc_id) { _gc_id = gc_id; }
791 uint gc_id() { return _gc_id; }
792 };
793
794 // Worker threads are named and have an id of an assigned work.
795 class WorkerThread: public NamedThread {
796 private:
797 uint _id;
798 public:
799 WorkerThread() : _id(0) { }
800 virtual bool is_Worker_thread() const { return true; }
801
802 virtual WorkerThread* as_Worker_thread() const {
803 assert(is_Worker_thread(), "Dubious cast to WorkerThread*?");
804 return (WorkerThread*) this;
805 }
806
807 void set_id(uint work_id) { _id = work_id; }
808 uint id() const { return _id; }
809 };
810
811 // A single WatcherThread is used for simulating timer interrupts.
812 class WatcherThread: public Thread {
813 friend class VMStructs;
814 public:
815 virtual void run();
816
817 private:
818 static WatcherThread* _watcher_thread;
819
820 static bool _startable;
821 // volatile due to at least one lock-free read
822 volatile static bool _should_terminate;
823 public:
824 enum SomeConstants {
825 delay_interval = 10 // interrupt delay in milliseconds
826 };
827
828 // Constructor
829 WatcherThread();
830
831 // No destruction allowed
832 ~WatcherThread() {
833 guarantee(false, "WatcherThread deletion must fix the race with VM termination");
834 }
835
836 // Tester
837 bool is_Watcher_thread() const { return true; }
838
839 // Printing
840 char* name() const { return (char*)"VM Periodic Task Thread"; }
841 void print_on(outputStream* st) const;
842 void unpark();
843
844 // Returns the single instance of WatcherThread
845 static WatcherThread* watcher_thread() { return _watcher_thread; }
846
847 // Create and start the single instance of WatcherThread, or stop it on shutdown
848 static void start();
849 static void stop();
850 // Only allow start once the VM is sufficiently initialized
851 // Otherwise the first task to enroll will trigger the start
852 static void make_startable();
853 private:
854 int sleep() const;
855 };
856
857
858 class CompilerThread;
859
860 typedef void (*ThreadFunction)(JavaThread*, TRAPS);
861
862 class JavaThread: public Thread {
863 friend class VMStructs;
864 friend class JVMCIVMStructs;
865 friend class WhiteBox;
866 private:
867 JavaThread* _next; // The next thread in the Threads list
868 bool _on_thread_list; // Is set when this JavaThread is added to the Threads list
869 oop _threadObj; // The Java level thread object
870
871 #ifdef ASSERT
872 private:
873 int _java_call_counter;
874
875 public:
876 int java_call_counter() { return _java_call_counter; }
877 void inc_java_call_counter() { _java_call_counter++; }
878 void dec_java_call_counter() {
879 assert(_java_call_counter > 0, "Invalid nesting of JavaCallWrapper");
880 _java_call_counter--;
881 }
882 private: // restore original namespace restriction
883 #endif // ifdef ASSERT
884
885 #ifndef PRODUCT
886 public:
887 enum {
888 jump_ring_buffer_size = 16
889 };
890 private: // restore original namespace restriction
891 #endif
892
893 JavaFrameAnchor _anchor; // Encapsulation of current java frame and it state
894
895 ThreadFunction _entry_point;
896
897 JNIEnv _jni_environment;
898
899 // Deopt support
900 DeoptResourceMark* _deopt_mark; // Holds special ResourceMark for deoptimization
901
902 intptr_t* _must_deopt_id; // id of frame that needs to be deopted once we
903 // transition out of native
904 CompiledMethod* _deopt_nmethod; // CompiledMethod that is currently being deoptimized
905 vframeArray* _vframe_array_head; // Holds the heap of the active vframeArrays
906 vframeArray* _vframe_array_last; // Holds last vFrameArray we popped
907 // Because deoptimization is lazy we must save jvmti requests to set locals
908 // in compiled frames until we deoptimize and we have an interpreter frame.
909 // This holds the pointer to array (yeah like there might be more than one) of
910 // description of compiled vframes that have locals that need to be updated.
911 GrowableArray<jvmtiDeferredLocalVariableSet*>* _deferred_locals_updates;
912
913 // Handshake value for fixing 6243940. We need a place for the i2c
914 // adapter to store the callee Method*. This value is NEVER live
915 // across a gc point so it does NOT have to be gc'd
916 // The handshake is open ended since we can't be certain that it will
917 // be NULLed. This is because we rarely ever see the race and end up
918 // in handle_wrong_method which is the backend of the handshake. See
919 // code in i2c adapters and handle_wrong_method.
920
921 Method* _callee_target;
922
923 // Used to pass back results to the interpreter or generated code running Java code.
924 oop _vm_result; // oop result is GC-preserved
925 Metadata* _vm_result_2; // non-oop result
926
927 // See ReduceInitialCardMarks: this holds the precise space interval of
928 // the most recent slow path allocation for which compiled code has
929 // elided card-marks for performance along the fast-path.
930 MemRegion _deferred_card_mark;
931
932 MonitorChunk* _monitor_chunks; // Contains the off stack monitors
933 // allocated during deoptimization
934 // and by JNI_MonitorEnter/Exit
935
936 // Async. requests support
937 enum AsyncRequests {
938 _no_async_condition = 0,
939 _async_exception,
940 _async_unsafe_access_error
941 };
942 AsyncRequests _special_runtime_exit_condition; // Enum indicating pending async. request
943 oop _pending_async_exception;
944
945 // Safepoint support
946 public: // Expose _thread_state for SafeFetchInt()
947 volatile JavaThreadState _thread_state;
948 private:
949 ThreadSafepointState *_safepoint_state; // Holds information about a thread during a safepoint
950 address _saved_exception_pc; // Saved pc of instruction where last implicit exception happened
951
952 // JavaThread termination support
953 enum TerminatedTypes {
954 _not_terminated = 0xDEAD - 2,
955 _thread_exiting, // JavaThread::exit() has been called for this thread
956 _thread_terminated, // JavaThread is removed from thread list
957 _vm_exited // JavaThread is still executing native code, but VM is terminated
958 // only VM_Exit can set _vm_exited
959 };
960
961 // In general a JavaThread's _terminated field transitions as follows:
962 //
963 // _not_terminated => _thread_exiting => _thread_terminated
964 //
965 // _vm_exited is a special value to cover the case of a JavaThread
966 // executing native code after the VM itself is terminated.
967 volatile TerminatedTypes _terminated;
968 // suspend/resume support
969 volatile bool _suspend_equivalent; // Suspend equivalent condition
970 jint _in_deopt_handler; // count of deoptimization
971 // handlers thread is in
972 volatile bool _doing_unsafe_access; // Thread may fault due to unsafe access
973 bool _do_not_unlock_if_synchronized; // Do not unlock the receiver of a synchronized method (since it was
974 // never locked) when throwing an exception. Used by interpreter only.
975
976 // JNI attach states:
977 enum JNIAttachStates {
978 _not_attaching_via_jni = 1, // thread is not attaching via JNI
979 _attaching_via_jni, // thread is attaching via JNI
980 _attached_via_jni // thread has attached via JNI
981 };
982
983 // A regular JavaThread's _jni_attach_state is _not_attaching_via_jni.
984 // A native thread that is attaching via JNI starts with a value
985 // of _attaching_via_jni and transitions to _attached_via_jni.
986 volatile JNIAttachStates _jni_attach_state;
987
988 public:
989 // State of the stack guard pages for this thread.
990 enum StackGuardState {
991 stack_guard_unused, // not needed
992 stack_guard_reserved_disabled,
993 stack_guard_yellow_reserved_disabled,// disabled (temporarily) after stack overflow
994 stack_guard_enabled // enabled
995 };
996
997 private:
998
999 #if INCLUDE_JVMCI
1000 // The _pending_* fields below are used to communicate extra information
1001 // from an uncommon trap in JVMCI compiled code to the uncommon trap handler.
1002
1003 // Communicates the DeoptReason and DeoptAction of the uncommon trap
1004 int _pending_deoptimization;
1005
1006 // Specifies whether the uncommon trap is to bci 0 of a synchronized method
1007 // before the monitor has been acquired.
1008 bool _pending_monitorenter;
1009
1010 // Specifies if the DeoptReason for the last uncommon trap was Reason_transfer_to_interpreter
1011 bool _pending_transfer_to_interpreter;
1012
1013 // Guard for re-entrant call to JVMCIRuntime::adjust_comp_level
1014 bool _adjusting_comp_level;
1015
1016 // An object that JVMCI compiled code can use to further describe and
1017 // uniquely identify the speculative optimization guarded by the uncommon trap
1018 oop _pending_failed_speculation;
1019
1020 // These fields are mutually exclusive in terms of live ranges.
1021 union {
1022 // Communicates the pc at which the most recent implicit exception occurred
1023 // from the signal handler to a deoptimization stub.
1024 address _implicit_exception_pc;
1025
1026 // Communicates an alternative call target to an i2c stub from a JavaCall .
1027 address _alternate_call_target;
1028 } _jvmci;
1029
1030 // Support for high precision, thread sensitive counters in JVMCI compiled code.
1031 jlong* _jvmci_counters;
1032
1033 public:
1034 static jlong* _jvmci_old_thread_counters;
1035 static void collect_counters(typeArrayOop array);
1036 private:
1037 #endif // INCLUDE_JVMCI
1038
1039 StackGuardState _stack_guard_state;
1040
1041 // Precompute the limit of the stack as used in stack overflow checks.
1042 // We load it from here to simplify the stack overflow check in assembly.
1043 address _stack_overflow_limit;
1044 address _reserved_stack_activation;
1045
1046 // Compiler exception handling (NOTE: The _exception_oop is *NOT* the same as _pending_exception. It is
1047 // used to temp. parsing values into and out of the runtime system during exception handling for compiled
1048 // code)
1049 volatile oop _exception_oop; // Exception thrown in compiled code
1050 volatile address _exception_pc; // PC where exception happened
1051 volatile address _exception_handler_pc; // PC for handler of exception
1052 volatile int _is_method_handle_return; // true (== 1) if the current exception PC is a MethodHandle call site.
1053
1054 private:
1055 // support for JNI critical regions
1056 jint _jni_active_critical; // count of entries into JNI critical region
1057
1058 // Checked JNI: function name requires exception check
1059 char* _pending_jni_exception_check_fn;
1060
1061 // For deadlock detection.
1062 int _depth_first_number;
1063
1064 // JVMTI PopFrame support
1065 // This is set to popframe_pending to signal that top Java frame should be popped immediately
1066 int _popframe_condition;
1067
1068 // If reallocation of scalar replaced objects fails, we throw OOM
1069 // and during exception propagation, pop the top
1070 // _frames_to_pop_failed_realloc frames, the ones that reference
1071 // failed reallocations.
1072 int _frames_to_pop_failed_realloc;
1073
1074 #ifndef PRODUCT
1075 int _jmp_ring_index;
1076 struct {
1077 // We use intptr_t instead of address so debugger doesn't try and display strings
1078 intptr_t _target;
1079 intptr_t _instruction;
1080 const char* _file;
1081 int _line;
1082 } _jmp_ring[jump_ring_buffer_size];
1083 #endif // PRODUCT
1084
1085 #if INCLUDE_ALL_GCS
1086 // Support for G1 barriers
1087
1088 SATBMarkQueue _satb_mark_queue; // Thread-local log for SATB barrier.
1089 // Set of all such queues.
1090 static SATBMarkQueueSet _satb_mark_queue_set;
1091
1092 DirtyCardQueue _dirty_card_queue; // Thread-local log for dirty cards.
1093 // Set of all such queues.
1094 static DirtyCardQueueSet _dirty_card_queue_set;
1095
1096 void flush_barrier_queues();
1097
1098 // Support for Shenandoah barriers
1099 static char _gc_state_global;
1100 char _gc_state;
1101
1102 #endif // INCLUDE_ALL_GCS
1103
1104 friend class VMThread;
1105 friend class ThreadWaitTransition;
1106 friend class VM_Exit;
1107
1108 void initialize(); // Initialized the instance variables
1109
1110 public:
1111 // Constructor
1112 JavaThread(bool is_attaching_via_jni = false); // for main thread and JNI attached threads
1113 JavaThread(ThreadFunction entry_point, size_t stack_size = 0);
1114 ~JavaThread();
1115
1116 #ifdef ASSERT
1117 // verify this JavaThread hasn't be published in the Threads::list yet
1118 void verify_not_published();
1119 #endif
1120
1121 //JNI functiontable getter/setter for JVMTI jni function table interception API.
1122 void set_jni_functions(struct JNINativeInterface_* functionTable) {
1123 _jni_environment.functions = functionTable;
1124 }
1125 struct JNINativeInterface_* get_jni_functions() {
1126 return (struct JNINativeInterface_ *)_jni_environment.functions;
1127 }
1128
1129 // This function is called at thread creation to allow
1130 // platform specific thread variables to be initialized.
1131 void cache_global_variables();
1132
1133 // Executes Shutdown.shutdown()
1134 void invoke_shutdown_hooks();
1135
1136 // Cleanup on thread exit
1137 enum ExitType {
1138 normal_exit,
1139 jni_detach
1140 };
1141 void exit(bool destroy_vm, ExitType exit_type = normal_exit);
1142
1143 void cleanup_failed_attach_current_thread();
1144
1145 // Testers
1146 virtual bool is_Java_thread() const { return true; }
1147 virtual bool can_call_java() const { return true; }
1148
1149 // Thread chain operations
1150 JavaThread* next() const { return _next; }
1151 void set_next(JavaThread* p) { _next = p; }
1152
1153 // Thread oop. threadObj() can be NULL for initial JavaThread
1154 // (or for threads attached via JNI)
1155 oop threadObj() const { return _threadObj; }
1156 void set_threadObj(oop p) { _threadObj = p; }
1157
1158 ThreadPriority java_priority() const; // Read from threadObj()
1159
1160 // Prepare thread and add to priority queue. If a priority is
1161 // not specified, use the priority of the thread object. Threads_lock
1162 // must be held while this function is called.
1163 void prepare(jobject jni_thread, ThreadPriority prio=NoPriority);
1164 void prepare_ext();
1165
1166 void set_saved_exception_pc(address pc) { _saved_exception_pc = pc; }
1167 address saved_exception_pc() { return _saved_exception_pc; }
1168
1169
1170 ThreadFunction entry_point() const { return _entry_point; }
1171
1172 // Allocates a new Java level thread object for this thread. thread_name may be NULL.
1173 void allocate_threadObj(Handle thread_group, const char* thread_name, bool daemon, TRAPS);
1174
1175 // Last frame anchor routines
1176
1177 JavaFrameAnchor* frame_anchor(void) { return &_anchor; }
1178
1179 // last_Java_sp
1180 bool has_last_Java_frame() const { return _anchor.has_last_Java_frame(); }
1181 intptr_t* last_Java_sp() const { return _anchor.last_Java_sp(); }
1182
1183 // last_Java_pc
1184
1185 address last_Java_pc(void) { return _anchor.last_Java_pc(); }
1186
1187 // Safepoint support
1188 #if !(defined(PPC64) || defined(AARCH64))
1189 JavaThreadState thread_state() const { return _thread_state; }
1190 void set_thread_state(JavaThreadState s) { _thread_state = s; }
1191 #else
1192 // Use membars when accessing volatile _thread_state. See
1193 // Threads::create_vm() for size checks.
1194 inline JavaThreadState thread_state() const;
1195 inline void set_thread_state(JavaThreadState s);
1196 #endif
1197 ThreadSafepointState *safepoint_state() const { return _safepoint_state; }
1198 void set_safepoint_state(ThreadSafepointState *state) { _safepoint_state = state; }
1199 bool is_at_poll_safepoint() { return _safepoint_state->is_at_poll_safepoint(); }
1200
1201 // JavaThread termination and lifecycle support:
1202 void smr_delete();
1203 bool on_thread_list() const { return _on_thread_list; }
1204 void set_on_thread_list() { _on_thread_list = true; }
1205
1206 // thread has called JavaThread::exit() or is terminated
1207 bool is_exiting() const;
1208 // thread is terminated (no longer on the threads list); we compare
1209 // against the two non-terminated values so that a freed JavaThread
1210 // will also be considered terminated.
1211 bool check_is_terminated(TerminatedTypes l_terminated) const {
1212 return l_terminated != _not_terminated && l_terminated != _thread_exiting;
1213 }
1214 bool is_terminated() const;
1215 void set_terminated(TerminatedTypes t);
1216 // special for Threads::remove() which is static:
1217 void set_terminated_value();
1218 void block_if_vm_exited();
1219
1220 bool doing_unsafe_access() { return _doing_unsafe_access; }
1221 void set_doing_unsafe_access(bool val) { _doing_unsafe_access = val; }
1222
1223 bool do_not_unlock_if_synchronized() { return _do_not_unlock_if_synchronized; }
1224 void set_do_not_unlock_if_synchronized(bool val) { _do_not_unlock_if_synchronized = val; }
1225
1226 inline void set_polling_page(void* poll_value);
1227 inline volatile void* get_polling_page();
1228
1229 private:
1230 // Support for thread handshake operations
1231 HandshakeState _handshake;
1232 public:
1233 void set_handshake_operation(HandshakeOperation* op) {
1234 _handshake.set_operation(this, op);
1235 }
1236
1237 bool has_handshake() const {
1238 return _handshake.has_operation();
1239 }
1240
1241 void cancel_handshake() {
1242 _handshake.cancel(this);
1243 }
1244
1245 void handshake_process_by_self() {
1246 _handshake.process_by_self(this);
1247 }
1248
1249 void handshake_process_by_vmthread() {
1250 _handshake.process_by_vmthread(this);
1251 }
1252
1253 // Suspend/resume support for JavaThread
1254 private:
1255 inline void set_ext_suspended();
1256 inline void clear_ext_suspended();
1257
1258 public:
1259 void java_suspend();
1260 void java_resume();
1261 int java_suspend_self();
1262
1263 void check_and_wait_while_suspended() {
1264 assert(JavaThread::current() == this, "sanity check");
1265
1266 bool do_self_suspend;
1267 do {
1268 // were we externally suspended while we were waiting?
1269 do_self_suspend = handle_special_suspend_equivalent_condition();
1270 if (do_self_suspend) {
1271 // don't surprise the thread that suspended us by returning
1272 java_suspend_self();
1273 set_suspend_equivalent();
1274 }
1275 } while (do_self_suspend);
1276 }
1277 static void check_safepoint_and_suspend_for_native_trans(JavaThread *thread);
1278 // Check for async exception in addition to safepoint and suspend request.
1279 static void check_special_condition_for_native_trans(JavaThread *thread);
1280
1281 // Same as check_special_condition_for_native_trans but finishes the
1282 // transition into thread_in_Java mode so that it can potentially
1283 // block.
1284 static void check_special_condition_for_native_trans_and_transition(JavaThread *thread);
1285
1286 bool is_ext_suspend_completed(bool called_by_wait, int delay, uint32_t *bits);
1287 bool is_ext_suspend_completed_with_lock(uint32_t *bits) {
1288 MutexLockerEx ml(SR_lock(), Mutex::_no_safepoint_check_flag);
1289 // Warning: is_ext_suspend_completed() may temporarily drop the
1290 // SR_lock to allow the thread to reach a stable thread state if
1291 // it is currently in a transient thread state.
1292 return is_ext_suspend_completed(false /* !called_by_wait */,
1293 SuspendRetryDelay, bits);
1294 }
1295
1296 // We cannot allow wait_for_ext_suspend_completion() to run forever or
1297 // we could hang. SuspendRetryCount and SuspendRetryDelay are normally
1298 // passed as the count and delay parameters. Experiments with specific
1299 // calls to wait_for_ext_suspend_completion() can be done by passing
1300 // other values in the code. Experiments with all calls can be done
1301 // via the appropriate -XX options.
1302 bool wait_for_ext_suspend_completion(int count, int delay, uint32_t *bits);
1303
1304 // test for suspend - most (all?) of these should go away
1305 bool is_thread_fully_suspended(bool wait_for_suspend, uint32_t *bits);
1306
1307 inline void set_external_suspend();
1308 inline void clear_external_suspend();
1309
1310 inline void set_deopt_suspend();
1311 inline void clear_deopt_suspend();
1312 bool is_deopt_suspend() { return (_suspend_flags & _deopt_suspend) != 0; }
1313
1314 bool is_external_suspend() const {
1315 return (_suspend_flags & _external_suspend) != 0;
1316 }
1317 // Whenever a thread transitions from native to vm/java it must suspend
1318 // if external|deopt suspend is present.
1319 bool is_suspend_after_native() const {
1320 return (_suspend_flags & (_external_suspend | _deopt_suspend)) != 0;
1321 }
1322
1323 // external suspend request is completed
1324 bool is_ext_suspended() const {
1325 return (_suspend_flags & _ext_suspended) != 0;
1326 }
1327
1328 bool is_external_suspend_with_lock() const {
1329 MutexLockerEx ml(SR_lock(), Mutex::_no_safepoint_check_flag);
1330 return is_external_suspend();
1331 }
1332
1333 // Special method to handle a pending external suspend request
1334 // when a suspend equivalent condition lifts.
1335 bool handle_special_suspend_equivalent_condition() {
1336 assert(is_suspend_equivalent(),
1337 "should only be called in a suspend equivalence condition");
1338 MutexLockerEx ml(SR_lock(), Mutex::_no_safepoint_check_flag);
1339 bool ret = is_external_suspend();
1340 if (!ret) {
1341 // not about to self-suspend so clear suspend equivalence
1342 clear_suspend_equivalent();
1343 }
1344 // implied else:
1345 // We have a pending external suspend request so we leave the
1346 // suspend_equivalent flag set until java_suspend_self() sets
1347 // the ext_suspended flag and clears the suspend_equivalent
1348 // flag. This insures that wait_for_ext_suspend_completion()
1349 // will return consistent values.
1350 return ret;
1351 }
1352
1353 // utility methods to see if we are doing some kind of suspension
1354 bool is_being_ext_suspended() const {
1355 MutexLockerEx ml(SR_lock(), Mutex::_no_safepoint_check_flag);
1356 return is_ext_suspended() || is_external_suspend();
1357 }
1358
1359 bool is_suspend_equivalent() const { return _suspend_equivalent; }
1360
1361 void set_suspend_equivalent() { _suspend_equivalent = true; }
1362 void clear_suspend_equivalent() { _suspend_equivalent = false; }
1363
1364 // Thread.stop support
1365 void send_thread_stop(oop throwable);
1366 AsyncRequests clear_special_runtime_exit_condition() {
1367 AsyncRequests x = _special_runtime_exit_condition;
1368 _special_runtime_exit_condition = _no_async_condition;
1369 return x;
1370 }
1371
1372 // Are any async conditions present?
1373 bool has_async_condition() { return (_special_runtime_exit_condition != _no_async_condition); }
1374
1375 void check_and_handle_async_exceptions(bool check_unsafe_error = true);
1376
1377 // these next two are also used for self-suspension and async exception support
1378 void handle_special_runtime_exit_condition(bool check_asyncs = true);
1379
1380 // Return true if JavaThread has an asynchronous condition or
1381 // if external suspension is requested.
1382 bool has_special_runtime_exit_condition() {
1383 // Because we don't use is_external_suspend_with_lock
1384 // it is possible that we won't see an asynchronous external suspend
1385 // request that has just gotten started, i.e., SR_lock grabbed but
1386 // _external_suspend field change either not made yet or not visible
1387 // yet. However, this is okay because the request is asynchronous and
1388 // we will see the new flag value the next time through. It's also
1389 // possible that the external suspend request is dropped after
1390 // we have checked is_external_suspend(), we will recheck its value
1391 // under SR_lock in java_suspend_self().
1392 return (_special_runtime_exit_condition != _no_async_condition) ||
1393 is_external_suspend() || is_trace_suspend();
1394 }
1395
1396 void set_pending_unsafe_access_error() { _special_runtime_exit_condition = _async_unsafe_access_error; }
1397
1398 inline void set_pending_async_exception(oop e);
1399
1400 // Fast-locking support
1401 bool is_lock_owned(address adr) const;
1402
1403 // Accessors for vframe array top
1404 // The linked list of vframe arrays are sorted on sp. This means when we
1405 // unpack the head must contain the vframe array to unpack.
1406 void set_vframe_array_head(vframeArray* value) { _vframe_array_head = value; }
1407 vframeArray* vframe_array_head() const { return _vframe_array_head; }
1408
1409 // Side structure for deferring update of java frame locals until deopt occurs
1410 GrowableArray<jvmtiDeferredLocalVariableSet*>* deferred_locals() const { return _deferred_locals_updates; }
1411 void set_deferred_locals(GrowableArray<jvmtiDeferredLocalVariableSet *>* vf) { _deferred_locals_updates = vf; }
1412
1413 // These only really exist to make debugging deopt problems simpler
1414
1415 void set_vframe_array_last(vframeArray* value) { _vframe_array_last = value; }
1416 vframeArray* vframe_array_last() const { return _vframe_array_last; }
1417
1418 // The special resourceMark used during deoptimization
1419
1420 void set_deopt_mark(DeoptResourceMark* value) { _deopt_mark = value; }
1421 DeoptResourceMark* deopt_mark(void) { return _deopt_mark; }
1422
1423 intptr_t* must_deopt_id() { return _must_deopt_id; }
1424 void set_must_deopt_id(intptr_t* id) { _must_deopt_id = id; }
1425 void clear_must_deopt_id() { _must_deopt_id = NULL; }
1426
1427 void set_deopt_compiled_method(CompiledMethod* nm) { _deopt_nmethod = nm; }
1428 CompiledMethod* deopt_compiled_method() { return _deopt_nmethod; }
1429
1430 Method* callee_target() const { return _callee_target; }
1431 void set_callee_target (Method* x) { _callee_target = x; }
1432
1433 // Oop results of vm runtime calls
1434 oop vm_result() const { return _vm_result; }
1435 void set_vm_result (oop x) { _vm_result = x; }
1436
1437 Metadata* vm_result_2() const { return _vm_result_2; }
1438 void set_vm_result_2 (Metadata* x) { _vm_result_2 = x; }
1439
1440 MemRegion deferred_card_mark() const { return _deferred_card_mark; }
1441 void set_deferred_card_mark(MemRegion mr) { _deferred_card_mark = mr; }
1442
1443 #if INCLUDE_JVMCI
1444 int pending_deoptimization() const { return _pending_deoptimization; }
1445 oop pending_failed_speculation() const { return _pending_failed_speculation; }
1446 bool adjusting_comp_level() const { return _adjusting_comp_level; }
1447 void set_adjusting_comp_level(bool b) { _adjusting_comp_level = b; }
1448 bool has_pending_monitorenter() const { return _pending_monitorenter; }
1449 void set_pending_monitorenter(bool b) { _pending_monitorenter = b; }
1450 void set_pending_deoptimization(int reason) { _pending_deoptimization = reason; }
1451 void set_pending_failed_speculation(oop failed_speculation) { _pending_failed_speculation = failed_speculation; }
1452 void set_pending_transfer_to_interpreter(bool b) { _pending_transfer_to_interpreter = b; }
1453 void set_jvmci_alternate_call_target(address a) { assert(_jvmci._alternate_call_target == NULL, "must be"); _jvmci._alternate_call_target = a; }
1454 void set_jvmci_implicit_exception_pc(address a) { assert(_jvmci._implicit_exception_pc == NULL, "must be"); _jvmci._implicit_exception_pc = a; }
1455 #endif // INCLUDE_JVMCI
1456
1457 // Exception handling for compiled methods
1458 oop exception_oop() const { return _exception_oop; }
1459 address exception_pc() const { return _exception_pc; }
1460 address exception_handler_pc() const { return _exception_handler_pc; }
1461 bool is_method_handle_return() const { return _is_method_handle_return == 1; }
1462
1463 void set_exception_oop(oop o) { (void)const_cast<oop&>(_exception_oop = o); }
1464 void set_exception_pc(address a) { _exception_pc = a; }
1465 void set_exception_handler_pc(address a) { _exception_handler_pc = a; }
1466 void set_is_method_handle_return(bool value) { _is_method_handle_return = value ? 1 : 0; }
1467
1468 void clear_exception_oop_and_pc() {
1469 set_exception_oop(NULL);
1470 set_exception_pc(NULL);
1471 }
1472
1473 // Stack overflow support
1474 //
1475 // (small addresses)
1476 //
1477 // -- <-- stack_end() ---
1478 // | |
1479 // | red pages |
1480 // | |
1481 // -- <-- stack_red_zone_base() |
1482 // | |
1483 // | guard
1484 // | yellow pages zone
1485 // | |
1486 // | |
1487 // -- <-- stack_yellow_zone_base() |
1488 // | |
1489 // | |
1490 // | reserved pages |
1491 // | |
1492 // -- <-- stack_reserved_zone_base() --- ---
1493 // /|\ shadow <-- stack_overflow_limit() (somewhere in here)
1494 // | zone
1495 // \|/ size
1496 // some untouched memory ---
1497 //
1498 //
1499 // --
1500 // |
1501 // | shadow zone
1502 // |
1503 // --
1504 // x frame n
1505 // --
1506 // x frame n-1
1507 // x
1508 // --
1509 // ...
1510 //
1511 // --
1512 // x frame 0
1513 // -- <-- stack_base()
1514 //
1515 // (large addresses)
1516 //
1517
1518 private:
1519 // These values are derived from flags StackRedPages, StackYellowPages,
1520 // StackReservedPages and StackShadowPages. The zone size is determined
1521 // ergonomically if page_size > 4K.
1522 static size_t _stack_red_zone_size;
1523 static size_t _stack_yellow_zone_size;
1524 static size_t _stack_reserved_zone_size;
1525 static size_t _stack_shadow_zone_size;
1526 public:
1527 inline size_t stack_available(address cur_sp);
1528
1529 static size_t stack_red_zone_size() {
1530 assert(_stack_red_zone_size > 0, "Don't call this before the field is initialized.");
1531 return _stack_red_zone_size;
1532 }
1533 static void set_stack_red_zone_size(size_t s) {
1534 assert(is_aligned(s, os::vm_page_size()),
1535 "We can not protect if the red zone size is not page aligned.");
1536 assert(_stack_red_zone_size == 0, "This should be called only once.");
1537 _stack_red_zone_size = s;
1538 }
1539 address stack_red_zone_base() {
1540 return (address)(stack_end() + stack_red_zone_size());
1541 }
1542 bool in_stack_red_zone(address a) {
1543 return a <= stack_red_zone_base() && a >= stack_end();
1544 }
1545
1546 static size_t stack_yellow_zone_size() {
1547 assert(_stack_yellow_zone_size > 0, "Don't call this before the field is initialized.");
1548 return _stack_yellow_zone_size;
1549 }
1550 static void set_stack_yellow_zone_size(size_t s) {
1551 assert(is_aligned(s, os::vm_page_size()),
1552 "We can not protect if the yellow zone size is not page aligned.");
1553 assert(_stack_yellow_zone_size == 0, "This should be called only once.");
1554 _stack_yellow_zone_size = s;
1555 }
1556
1557 static size_t stack_reserved_zone_size() {
1558 // _stack_reserved_zone_size may be 0. This indicates the feature is off.
1559 return _stack_reserved_zone_size;
1560 }
1561 static void set_stack_reserved_zone_size(size_t s) {
1562 assert(is_aligned(s, os::vm_page_size()),
1563 "We can not protect if the reserved zone size is not page aligned.");
1564 assert(_stack_reserved_zone_size == 0, "This should be called only once.");
1565 _stack_reserved_zone_size = s;
1566 }
1567 address stack_reserved_zone_base() {
1568 return (address)(stack_end() +
1569 (stack_red_zone_size() + stack_yellow_zone_size() + stack_reserved_zone_size()));
1570 }
1571 bool in_stack_reserved_zone(address a) {
1572 return (a <= stack_reserved_zone_base()) &&
1573 (a >= (address)((intptr_t)stack_reserved_zone_base() - stack_reserved_zone_size()));
1574 }
1575
1576 static size_t stack_yellow_reserved_zone_size() {
1577 return _stack_yellow_zone_size + _stack_reserved_zone_size;
1578 }
1579 bool in_stack_yellow_reserved_zone(address a) {
1580 return (a <= stack_reserved_zone_base()) && (a >= stack_red_zone_base());
1581 }
1582
1583 // Size of red + yellow + reserved zones.
1584 static size_t stack_guard_zone_size() {
1585 return stack_red_zone_size() + stack_yellow_reserved_zone_size();
1586 }
1587
1588 static size_t stack_shadow_zone_size() {
1589 assert(_stack_shadow_zone_size > 0, "Don't call this before the field is initialized.");
1590 return _stack_shadow_zone_size;
1591 }
1592 static void set_stack_shadow_zone_size(size_t s) {
1593 // The shadow area is not allocated or protected, so
1594 // it needs not be page aligned.
1595 // But the stack bang currently assumes that it is a
1596 // multiple of page size. This guarantees that the bang
1597 // loop touches all pages in the shadow zone.
1598 // This can be guaranteed differently, as well. E.g., if
1599 // the page size is a multiple of 4K, banging in 4K steps
1600 // suffices to touch all pages. (Some pages are banged
1601 // several times, though.)
1602 assert(is_aligned(s, os::vm_page_size()),
1603 "Stack bang assumes multiple of page size.");
1604 assert(_stack_shadow_zone_size == 0, "This should be called only once.");
1605 _stack_shadow_zone_size = s;
1606 }
1607
1608 void create_stack_guard_pages();
1609 void remove_stack_guard_pages();
1610
1611 void enable_stack_reserved_zone();
1612 void disable_stack_reserved_zone();
1613 void enable_stack_yellow_reserved_zone();
1614 void disable_stack_yellow_reserved_zone();
1615 void enable_stack_red_zone();
1616 void disable_stack_red_zone();
1617
1618 inline bool stack_guard_zone_unused();
1619 inline bool stack_yellow_reserved_zone_disabled();
1620 inline bool stack_reserved_zone_disabled();
1621 inline bool stack_guards_enabled();
1622
1623 address reserved_stack_activation() const { return _reserved_stack_activation; }
1624 void set_reserved_stack_activation(address addr) {
1625 assert(_reserved_stack_activation == stack_base()
1626 || _reserved_stack_activation == NULL
1627 || addr == stack_base(), "Must not be set twice");
1628 _reserved_stack_activation = addr;
1629 }
1630
1631 // Attempt to reguard the stack after a stack overflow may have occurred.
1632 // Returns true if (a) guard pages are not needed on this thread, (b) the
1633 // pages are already guarded, or (c) the pages were successfully reguarded.
1634 // Returns false if there is not enough stack space to reguard the pages, in
1635 // which case the caller should unwind a frame and try again. The argument
1636 // should be the caller's (approximate) sp.
1637 bool reguard_stack(address cur_sp);
1638 // Similar to above but see if current stackpoint is out of the guard area
1639 // and reguard if possible.
1640 bool reguard_stack(void);
1641
1642 address stack_overflow_limit() { return _stack_overflow_limit; }
1643 void set_stack_overflow_limit() {
1644 _stack_overflow_limit =
1645 stack_end() + MAX2(JavaThread::stack_guard_zone_size(), JavaThread::stack_shadow_zone_size());
1646 }
1647
1648 // Misc. accessors/mutators
1649 void set_do_not_unlock(void) { _do_not_unlock_if_synchronized = true; }
1650 void clr_do_not_unlock(void) { _do_not_unlock_if_synchronized = false; }
1651 bool do_not_unlock(void) { return _do_not_unlock_if_synchronized; }
1652
1653 #ifndef PRODUCT
1654 void record_jump(address target, address instr, const char* file, int line);
1655 #endif // PRODUCT
1656
1657 // For assembly stub generation
1658 static ByteSize threadObj_offset() { return byte_offset_of(JavaThread, _threadObj); }
1659 #ifndef PRODUCT
1660 static ByteSize jmp_ring_index_offset() { return byte_offset_of(JavaThread, _jmp_ring_index); }
1661 static ByteSize jmp_ring_offset() { return byte_offset_of(JavaThread, _jmp_ring); }
1662 #endif // PRODUCT
1663 static ByteSize jni_environment_offset() { return byte_offset_of(JavaThread, _jni_environment); }
1664 static ByteSize pending_jni_exception_check_fn_offset() {
1665 return byte_offset_of(JavaThread, _pending_jni_exception_check_fn);
1666 }
1667 static ByteSize last_Java_sp_offset() {
1668 return byte_offset_of(JavaThread, _anchor) + JavaFrameAnchor::last_Java_sp_offset();
1669 }
1670 static ByteSize last_Java_pc_offset() {
1671 return byte_offset_of(JavaThread, _anchor) + JavaFrameAnchor::last_Java_pc_offset();
1672 }
1673 static ByteSize frame_anchor_offset() {
1674 return byte_offset_of(JavaThread, _anchor);
1675 }
1676 static ByteSize callee_target_offset() { return byte_offset_of(JavaThread, _callee_target); }
1677 static ByteSize vm_result_offset() { return byte_offset_of(JavaThread, _vm_result); }
1678 static ByteSize vm_result_2_offset() { return byte_offset_of(JavaThread, _vm_result_2); }
1679 static ByteSize thread_state_offset() { return byte_offset_of(JavaThread, _thread_state); }
1680 static ByteSize saved_exception_pc_offset() { return byte_offset_of(JavaThread, _saved_exception_pc); }
1681 static ByteSize osthread_offset() { return byte_offset_of(JavaThread, _osthread); }
1682 #if INCLUDE_JVMCI
1683 static ByteSize pending_deoptimization_offset() { return byte_offset_of(JavaThread, _pending_deoptimization); }
1684 static ByteSize pending_monitorenter_offset() { return byte_offset_of(JavaThread, _pending_monitorenter); }
1685 static ByteSize pending_failed_speculation_offset() { return byte_offset_of(JavaThread, _pending_failed_speculation); }
1686 static ByteSize jvmci_alternate_call_target_offset() { return byte_offset_of(JavaThread, _jvmci._alternate_call_target); }
1687 static ByteSize jvmci_implicit_exception_pc_offset() { return byte_offset_of(JavaThread, _jvmci._implicit_exception_pc); }
1688 static ByteSize jvmci_counters_offset() { return byte_offset_of(JavaThread, _jvmci_counters); }
1689 #endif // INCLUDE_JVMCI
1690 static ByteSize exception_oop_offset() { return byte_offset_of(JavaThread, _exception_oop); }
1691 static ByteSize exception_pc_offset() { return byte_offset_of(JavaThread, _exception_pc); }
1692 static ByteSize exception_handler_pc_offset() { return byte_offset_of(JavaThread, _exception_handler_pc); }
1693 static ByteSize stack_overflow_limit_offset() { return byte_offset_of(JavaThread, _stack_overflow_limit); }
1694 static ByteSize is_method_handle_return_offset() { return byte_offset_of(JavaThread, _is_method_handle_return); }
1695 static ByteSize stack_guard_state_offset() { return byte_offset_of(JavaThread, _stack_guard_state); }
1696 static ByteSize reserved_stack_activation_offset() { return byte_offset_of(JavaThread, _reserved_stack_activation); }
1697 static ByteSize suspend_flags_offset() { return byte_offset_of(JavaThread, _suspend_flags); }
1698
1699 static ByteSize do_not_unlock_if_synchronized_offset() { return byte_offset_of(JavaThread, _do_not_unlock_if_synchronized); }
1700 static ByteSize should_post_on_exceptions_flag_offset() {
1701 return byte_offset_of(JavaThread, _should_post_on_exceptions_flag);
1702 }
1703
1704 #if INCLUDE_ALL_GCS
1705 static ByteSize satb_mark_queue_offset() { return byte_offset_of(JavaThread, _satb_mark_queue); }
1706 static ByteSize dirty_card_queue_offset() { return byte_offset_of(JavaThread, _dirty_card_queue); }
1707
1708 static ByteSize gc_state_offset() { return byte_offset_of(JavaThread, _gc_state); }
1709
1710 #endif // INCLUDE_ALL_GCS
1711
1712 // Returns the jni environment for this thread
1713 JNIEnv* jni_environment() { return &_jni_environment; }
1714
1715 static JavaThread* thread_from_jni_environment(JNIEnv* env) {
1716 JavaThread *thread_from_jni_env = (JavaThread*)((intptr_t)env - in_bytes(jni_environment_offset()));
1717 // Only return NULL if thread is off the thread list; starting to
1718 // exit should not return NULL.
1719 if (thread_from_jni_env->is_terminated()) {
1720 thread_from_jni_env->block_if_vm_exited();
1721 return NULL;
1722 } else {
1723 return thread_from_jni_env;
1724 }
1725 }
1726
1727 // JNI critical regions. These can nest.
1728 bool in_critical() { return _jni_active_critical > 0; }
1729 bool in_last_critical() { return _jni_active_critical == 1; }
1730 void enter_critical() {
1731 assert(Thread::current() == this ||
1732 (Thread::current()->is_VM_thread() &&
1733 SafepointSynchronize::is_synchronizing()),
1734 "this must be current thread or synchronizing");
1735 _jni_active_critical++;
1736 }
1737 void exit_critical() {
1738 assert(Thread::current() == this, "this must be current thread");
1739 _jni_active_critical--;
1740 assert(_jni_active_critical >= 0, "JNI critical nesting problem?");
1741 }
1742
1743 // Checked JNI: is the programmer required to check for exceptions, if so specify
1744 // which function name. Returning to a Java frame should implicitly clear the
1745 // pending check, this is done for Native->Java transitions (i.e. user JNI code).
1746 // VM->Java transistions are not cleared, it is expected that JNI code enclosed
1747 // within ThreadToNativeFromVM makes proper exception checks (i.e. VM internal).
1748 bool is_pending_jni_exception_check() const { return _pending_jni_exception_check_fn != NULL; }
1749 void clear_pending_jni_exception_check() { _pending_jni_exception_check_fn = NULL; }
1750 const char* get_pending_jni_exception_check() const { return _pending_jni_exception_check_fn; }
1751 void set_pending_jni_exception_check(const char* fn_name) { _pending_jni_exception_check_fn = (char*) fn_name; }
1752
1753 // For deadlock detection
1754 int depth_first_number() { return _depth_first_number; }
1755 void set_depth_first_number(int dfn) { _depth_first_number = dfn; }
1756
1757 private:
1758 void set_monitor_chunks(MonitorChunk* monitor_chunks) { _monitor_chunks = monitor_chunks; }
1759
1760 public:
1761 MonitorChunk* monitor_chunks() const { return _monitor_chunks; }
1762 void add_monitor_chunk(MonitorChunk* chunk);
1763 void remove_monitor_chunk(MonitorChunk* chunk);
1764 bool in_deopt_handler() const { return _in_deopt_handler > 0; }
1765 void inc_in_deopt_handler() { _in_deopt_handler++; }
1766 void dec_in_deopt_handler() {
1767 assert(_in_deopt_handler > 0, "mismatched deopt nesting");
1768 if (_in_deopt_handler > 0) { // robustness
1769 _in_deopt_handler--;
1770 }
1771 }
1772
1773 private:
1774 void set_entry_point(ThreadFunction entry_point) { _entry_point = entry_point; }
1775
1776 public:
1777
1778 // Frame iteration; calls the function f for all frames on the stack
1779 void frames_do(void f(frame*, const RegisterMap*));
1780
1781 // Memory operations
1782 void oops_do(OopClosure* f, CodeBlobClosure* cf);
1783
1784 // Sweeper operations
1785 virtual void nmethods_do(CodeBlobClosure* cf);
1786
1787 // RedefineClasses Support
1788 void metadata_do(void f(Metadata*));
1789
1790 // Misc. operations
1791 char* name() const { return (char*)get_thread_name(); }
1792 void print_on(outputStream* st) const;
1793 void print_value();
1794 void print_thread_state_on(outputStream*) const PRODUCT_RETURN;
1795 void print_thread_state() const PRODUCT_RETURN;
1796 void print_on_error(outputStream* st, char* buf, int buflen) const;
1797 void print_name_on_error(outputStream* st, char* buf, int buflen) const;
1798 void verify();
1799 const char* get_thread_name() const;
1800 private:
1801 // factor out low-level mechanics for use in both normal and error cases
1802 const char* get_thread_name_string(char* buf = NULL, int buflen = 0) const;
1803 public:
1804 const char* get_threadgroup_name() const;
1805 const char* get_parent_name() const;
1806
1807 // Accessing frames
1808 frame last_frame() {
1809 _anchor.make_walkable(this);
1810 return pd_last_frame();
1811 }
1812 javaVFrame* last_java_vframe(RegisterMap* reg_map);
1813
1814 // Returns method at 'depth' java or native frames down the stack
1815 // Used for security checks
1816 Klass* security_get_caller_class(int depth);
1817
1818 // Print stack trace in external format
1819 void print_stack_on(outputStream* st);
1820 void print_stack() { print_stack_on(tty); }
1821
1822 // Print stack traces in various internal formats
1823 void trace_stack() PRODUCT_RETURN;
1824 void trace_stack_from(vframe* start_vf) PRODUCT_RETURN;
1825 void trace_frames() PRODUCT_RETURN;
1826 void trace_oops() PRODUCT_RETURN;
1827
1828 // Print an annotated view of the stack frames
1829 void print_frame_layout(int depth = 0, bool validate_only = false) NOT_DEBUG_RETURN;
1830 void validate_frame_layout() {
1831 print_frame_layout(0, true);
1832 }
1833
1834 // Returns the number of stack frames on the stack
1835 int depth() const;
1836
1837 // Function for testing deoptimization
1838 void deoptimize();
1839 void make_zombies();
1840
1841 void deoptimized_wrt_marked_nmethods();
1842
1843 public:
1844 // Returns the running thread as a JavaThread
1845 static inline JavaThread* current();
1846
1847 // Returns the active Java thread. Do not use this if you know you are calling
1848 // from a JavaThread, as it's slower than JavaThread::current. If called from
1849 // the VMThread, it also returns the JavaThread that instigated the VMThread's
1850 // operation. You may not want that either.
1851 static JavaThread* active();
1852
1853 inline CompilerThread* as_CompilerThread();
1854
1855 public:
1856 virtual void run();
1857 void thread_main_inner();
1858
1859 private:
1860 // PRIVILEGED STACK
1861 PrivilegedElement* _privileged_stack_top;
1862 GrowableArray<oop>* _array_for_gc;
1863 public:
1864
1865 // Returns the privileged_stack information.
1866 PrivilegedElement* privileged_stack_top() const { return _privileged_stack_top; }
1867 void set_privileged_stack_top(PrivilegedElement *e) { _privileged_stack_top = e; }
1868 void register_array_for_gc(GrowableArray<oop>* array) { _array_for_gc = array; }
1869
1870 public:
1871 // Thread local information maintained by JVMTI.
1872 void set_jvmti_thread_state(JvmtiThreadState *value) { _jvmti_thread_state = value; }
1873 // A JvmtiThreadState is lazily allocated. This jvmti_thread_state()
1874 // getter is used to get this JavaThread's JvmtiThreadState if it has
1875 // one which means NULL can be returned. JvmtiThreadState::state_for()
1876 // is used to get the specified JavaThread's JvmtiThreadState if it has
1877 // one or it allocates a new JvmtiThreadState for the JavaThread and
1878 // returns it. JvmtiThreadState::state_for() will return NULL only if
1879 // the specified JavaThread is exiting.
1880 JvmtiThreadState *jvmti_thread_state() const { return _jvmti_thread_state; }
1881 static ByteSize jvmti_thread_state_offset() { return byte_offset_of(JavaThread, _jvmti_thread_state); }
1882 void set_jvmti_get_loaded_classes_closure(JvmtiGetLoadedClassesClosure* value) { _jvmti_get_loaded_classes_closure = value; }
1883 JvmtiGetLoadedClassesClosure* get_jvmti_get_loaded_classes_closure() const { return _jvmti_get_loaded_classes_closure; }
1884
1885 // JVMTI PopFrame support
1886 // Setting and clearing popframe_condition
1887 // All of these enumerated values are bits. popframe_pending
1888 // indicates that a PopFrame() has been requested and not yet been
1889 // completed. popframe_processing indicates that that PopFrame() is in
1890 // the process of being completed. popframe_force_deopt_reexecution_bit
1891 // indicates that special handling is required when returning to a
1892 // deoptimized caller.
1893 enum PopCondition {
1894 popframe_inactive = 0x00,
1895 popframe_pending_bit = 0x01,
1896 popframe_processing_bit = 0x02,
1897 popframe_force_deopt_reexecution_bit = 0x04
1898 };
1899 PopCondition popframe_condition() { return (PopCondition) _popframe_condition; }
1900 void set_popframe_condition(PopCondition c) { _popframe_condition = c; }
1901 void set_popframe_condition_bit(PopCondition c) { _popframe_condition |= c; }
1902 void clear_popframe_condition() { _popframe_condition = popframe_inactive; }
1903 static ByteSize popframe_condition_offset() { return byte_offset_of(JavaThread, _popframe_condition); }
1904 bool has_pending_popframe() { return (popframe_condition() & popframe_pending_bit) != 0; }
1905 bool popframe_forcing_deopt_reexecution() { return (popframe_condition() & popframe_force_deopt_reexecution_bit) != 0; }
1906 void clear_popframe_forcing_deopt_reexecution() { _popframe_condition &= ~popframe_force_deopt_reexecution_bit; }
1907 #ifdef CC_INTERP
1908 bool pop_frame_pending(void) { return ((_popframe_condition & popframe_pending_bit) != 0); }
1909 void clr_pop_frame_pending(void) { _popframe_condition = popframe_inactive; }
1910 bool pop_frame_in_process(void) { return ((_popframe_condition & popframe_processing_bit) != 0); }
1911 void set_pop_frame_in_process(void) { _popframe_condition |= popframe_processing_bit; }
1912 void clr_pop_frame_in_process(void) { _popframe_condition &= ~popframe_processing_bit; }
1913 #endif
1914
1915 int frames_to_pop_failed_realloc() const { return _frames_to_pop_failed_realloc; }
1916 void set_frames_to_pop_failed_realloc(int nb) { _frames_to_pop_failed_realloc = nb; }
1917 void dec_frames_to_pop_failed_realloc() { _frames_to_pop_failed_realloc--; }
1918
1919 private:
1920 // Saved incoming arguments to popped frame.
1921 // Used only when popped interpreted frame returns to deoptimized frame.
1922 void* _popframe_preserved_args;
1923 int _popframe_preserved_args_size;
1924
1925 public:
1926 void popframe_preserve_args(ByteSize size_in_bytes, void* start);
1927 void* popframe_preserved_args();
1928 ByteSize popframe_preserved_args_size();
1929 WordSize popframe_preserved_args_size_in_words();
1930 void popframe_free_preserved_args();
1931
1932
1933 private:
1934 JvmtiThreadState *_jvmti_thread_state;
1935 JvmtiGetLoadedClassesClosure* _jvmti_get_loaded_classes_closure;
1936
1937 // Used by the interpreter in fullspeed mode for frame pop, method
1938 // entry, method exit and single stepping support. This field is
1939 // only set to non-zero by the VM_EnterInterpOnlyMode VM operation.
1940 // It can be set to zero asynchronously (i.e., without a VM operation
1941 // or a lock) so we have to be very careful.
1942 int _interp_only_mode;
1943
1944 public:
1945 // used by the interpreter for fullspeed debugging support (see above)
1946 static ByteSize interp_only_mode_offset() { return byte_offset_of(JavaThread, _interp_only_mode); }
1947 bool is_interp_only_mode() { return (_interp_only_mode != 0); }
1948 int get_interp_only_mode() { return _interp_only_mode; }
1949 void increment_interp_only_mode() { ++_interp_only_mode; }
1950 void decrement_interp_only_mode() { --_interp_only_mode; }
1951
1952 // support for cached flag that indicates whether exceptions need to be posted for this thread
1953 // if this is false, we can avoid deoptimizing when events are thrown
1954 // this gets set to reflect whether jvmtiExport::post_exception_throw would actually do anything
1955 private:
1956 int _should_post_on_exceptions_flag;
1957
1958 public:
1959 int should_post_on_exceptions_flag() { return _should_post_on_exceptions_flag; }
1960 void set_should_post_on_exceptions_flag(int val) { _should_post_on_exceptions_flag = val; }
1961
1962 private:
1963 ThreadStatistics *_thread_stat;
1964
1965 public:
1966 ThreadStatistics* get_thread_stat() const { return _thread_stat; }
1967
1968 // Return a blocker object for which this thread is blocked parking.
1969 oop current_park_blocker();
1970
1971 private:
1972 static size_t _stack_size_at_create;
1973
1974 public:
1975 static inline size_t stack_size_at_create(void) {
1976 return _stack_size_at_create;
1977 }
1978 static inline void set_stack_size_at_create(size_t value) {
1979 _stack_size_at_create = value;
1980 }
1981
1982 #if INCLUDE_ALL_GCS
1983 // SATB marking queue support
1984 SATBMarkQueue& satb_mark_queue() { return _satb_mark_queue; }
1985 static SATBMarkQueueSet& satb_mark_queue_set() {
1986 return _satb_mark_queue_set;
1987 }
1988
1989 // Dirty card queue support
1990 DirtyCardQueue& dirty_card_queue() { return _dirty_card_queue; }
1991 static DirtyCardQueueSet& dirty_card_queue_set() {
1992 return _dirty_card_queue_set;
1993 }
1994
1995 inline char gc_state() const;
1996
1997 private:
1998 void set_gc_state(char in_prog);
1999
2000 public:
2001 static void set_gc_state_all_threads(char in_prog);
2002
2003 #endif // INCLUDE_ALL_GCS
2004
2005 // This method initializes the SATB and dirty card queues before a
2006 // JavaThread is added to the Java thread list. Right now, we don't
2007 // have to do anything to the dirty card queue (it should have been
2008 // activated when the thread was created), but we have to activate
2009 // the SATB queue if the thread is created while a marking cycle is
2010 // in progress. The activation / de-activation of the SATB queues at
2011 // the beginning / end of a marking cycle is done during safepoints
2012 // so we have to make sure this method is called outside one to be
2013 // able to safely read the active field of the SATB queue set. Right
2014 // now, it is called just before the thread is added to the Java
2015 // thread list in the Threads::add() method. That method is holding
2016 // the Threads_lock which ensures we are outside a safepoint. We
2017 // cannot do the obvious and set the active field of the SATB queue
2018 // when the thread is created given that, in some cases, safepoints
2019 // might happen between the JavaThread constructor being called and the
2020 // thread being added to the Java thread list (an example of this is
2021 // when the structure for the DestroyJavaVM thread is created).
2022 #if INCLUDE_ALL_GCS
2023 void initialize_queues();
2024 #else // INCLUDE_ALL_GCS
2025 void initialize_queues() { }
2026 #endif // INCLUDE_ALL_GCS
2027
2028 // Machine dependent stuff
2029 #include OS_CPU_HEADER(thread)
2030
2031 public:
2032 void set_blocked_on_compilation(bool value) {
2033 _blocked_on_compilation = value;
2034 }
2035
2036 bool blocked_on_compilation() {
2037 return _blocked_on_compilation;
2038 }
2039 protected:
2040 bool _blocked_on_compilation;
2041
2042
2043 // JSR166 per-thread parker
2044 private:
2045 Parker* _parker;
2046 public:
2047 Parker* parker() { return _parker; }
2048
2049 // Biased locking support
2050 private:
2051 GrowableArray<MonitorInfo*>* _cached_monitor_info;
2052 public:
2053 GrowableArray<MonitorInfo*>* cached_monitor_info() { return _cached_monitor_info; }
2054 void set_cached_monitor_info(GrowableArray<MonitorInfo*>* info) { _cached_monitor_info = info; }
2055
2056 // clearing/querying jni attach status
2057 bool is_attaching_via_jni() const { return _jni_attach_state == _attaching_via_jni; }
2058 bool has_attached_via_jni() const { return is_attaching_via_jni() || _jni_attach_state == _attached_via_jni; }
2059 inline void set_done_attaching_via_jni();
2060 };
2061
2062 // Inline implementation of JavaThread::current
2063 inline JavaThread* JavaThread::current() {
2064 Thread* thread = Thread::current();
2065 assert(thread->is_Java_thread(), "just checking");
2066 return (JavaThread*)thread;
2067 }
2068
2069 inline CompilerThread* JavaThread::as_CompilerThread() {
2070 assert(is_Compiler_thread(), "just checking");
2071 return (CompilerThread*)this;
2072 }
2073
2074 // Dedicated thread to sweep the code cache
2075 class CodeCacheSweeperThread : public JavaThread {
2076 CompiledMethod* _scanned_compiled_method; // nmethod being scanned by the sweeper
2077 public:
2078 CodeCacheSweeperThread();
2079 // Track the nmethod currently being scanned by the sweeper
2080 void set_scanned_compiled_method(CompiledMethod* cm) {
2081 assert(_scanned_compiled_method == NULL || cm == NULL, "should reset to NULL before writing a new value");
2082 _scanned_compiled_method = cm;
2083 }
2084
2085 // Hide sweeper thread from external view.
2086 bool is_hidden_from_external_view() const { return true; }
2087
2088 bool is_Code_cache_sweeper_thread() const { return true; }
2089
2090 // Prevent GC from unloading _scanned_compiled_method
2091 void oops_do(OopClosure* f, CodeBlobClosure* cf);
2092 void nmethods_do(CodeBlobClosure* cf);
2093 };
2094
2095 // A thread used for Compilation.
2096 class CompilerThread : public JavaThread {
2097 friend class VMStructs;
2098 private:
2099 CompilerCounters* _counters;
2100
2101 ciEnv* _env;
2102 CompileLog* _log;
2103 CompileTask* volatile _task; // print_threads_compiling can read this concurrently.
2104 CompileQueue* _queue;
2105 BufferBlob* _buffer_blob;
2106
2107 AbstractCompiler* _compiler;
2108
2109 public:
2110
2111 static CompilerThread* current();
2112
2113 CompilerThread(CompileQueue* queue, CompilerCounters* counters);
2114
2115 bool is_Compiler_thread() const { return true; }
2116
2117 virtual bool can_call_java() const;
2118
2119 // Hide native compiler threads from external view.
2120 bool is_hidden_from_external_view() const { return !can_call_java(); }
2121
2122 void set_compiler(AbstractCompiler* c) { _compiler = c; }
2123 AbstractCompiler* compiler() const { return _compiler; }
2124
2125 CompileQueue* queue() const { return _queue; }
2126 CompilerCounters* counters() const { return _counters; }
2127
2128 // Get/set the thread's compilation environment.
2129 ciEnv* env() { return _env; }
2130 void set_env(ciEnv* env) { _env = env; }
2131
2132 BufferBlob* get_buffer_blob() const { return _buffer_blob; }
2133 void set_buffer_blob(BufferBlob* b) { _buffer_blob = b; }
2134
2135 // Get/set the thread's logging information
2136 CompileLog* log() { return _log; }
2137 void init_log(CompileLog* log) {
2138 // Set once, for good.
2139 assert(_log == NULL, "set only once");
2140 _log = log;
2141 }
2142
2143 #ifndef PRODUCT
2144 private:
2145 IdealGraphPrinter *_ideal_graph_printer;
2146 public:
2147 IdealGraphPrinter *ideal_graph_printer() { return _ideal_graph_printer; }
2148 void set_ideal_graph_printer(IdealGraphPrinter *n) { _ideal_graph_printer = n; }
2149 #endif
2150
2151 // Get/set the thread's current task
2152 CompileTask* task() { return _task; }
2153 void set_task(CompileTask* task) { _task = task; }
2154 };
2155
2156 inline CompilerThread* CompilerThread::current() {
2157 return JavaThread::current()->as_CompilerThread();
2158 }
2159
2160 // The active thread queue. It also keeps track of the current used
2161 // thread priorities.
2162 class Threads: AllStatic {
2163 friend class VMStructs;
2164 private:
2165 static JavaThread* _thread_list;
2166 static int _number_of_threads;
2167 static int _number_of_non_daemon_threads;
2168 static int _return_code;
2169 static int _thread_claim_parity;
2170 #ifdef ASSERT
2171 static bool _vm_complete;
2172 #endif
2173
2174 static void initialize_java_lang_classes(JavaThread* main_thread, TRAPS);
2175 static void initialize_jsr292_core_classes(TRAPS);
2176
2177 public:
2178 // Thread management
2179 // force_daemon is a concession to JNI, where we may need to add a
2180 // thread to the thread list before allocating its thread object
2181 static void add(JavaThread* p, bool force_daemon = false);
2182 static void remove(JavaThread* p);
2183 static void threads_do(ThreadClosure* tc);
2184 static void java_threads_do(ThreadClosure* tc);
2185 static void possibly_parallel_threads_do(bool is_par, ThreadClosure* tc);
2186
2187 // Initializes the vm and creates the vm thread
2188 static jint create_vm(JavaVMInitArgs* args, bool* canTryAgain);
2189 static void convert_vm_init_libraries_to_agents();
2190 static void create_vm_init_libraries();
2191 static void create_vm_init_agents();
2192 static void shutdown_vm_agents();
2193 static bool destroy_vm();
2194 // Supported VM versions via JNI
2195 // Includes JNI_VERSION_1_1
2196 static jboolean is_supported_jni_version_including_1_1(jint version);
2197 // Does not include JNI_VERSION_1_1
2198 static jboolean is_supported_jni_version(jint version);
2199
2200 // The "thread claim parity" provides a way for threads to be claimed
2201 // by parallel worker tasks.
2202 //
2203 // Each thread contains a a "parity" field. A task will claim the
2204 // thread only if its parity field is the same as the global parity,
2205 // which is updated by calling change_thread_claim_parity().
2206 //
2207 // For this to work change_thread_claim_parity() needs to be called
2208 // exactly once in sequential code before starting parallel tasks
2209 // that should claim threads.
2210 //
2211 // New threads get their parity set to 0 and change_thread_claim_parity()
2212 // never set the global parity to 0.
2213 static int thread_claim_parity() { return _thread_claim_parity; }
2214 static void change_thread_claim_parity();
2215 static void assert_all_threads_claimed() NOT_DEBUG_RETURN;
2216
2217 // Apply "f->do_oop" to all root oops in all threads.
2218 // This version may only be called by sequential code.
2219 static void oops_do(OopClosure* f, CodeBlobClosure* cf);
2220 // This version may be called by sequential or parallel code.
2221 static void possibly_parallel_oops_do(bool is_par, OopClosure* f, CodeBlobClosure* cf, CodeBlobClosure* nmethods_cl = NULL, ThreadClosure* thread_cl = NULL);
2222 // This creates a list of GCTasks, one per thread.
2223 static void create_thread_roots_tasks(GCTaskQueue* q);
2224 // This creates a list of GCTasks, one per thread, for marking objects.
2225 static void create_thread_roots_marking_tasks(GCTaskQueue* q);
2226
2227 // Apply "f->do_oop" to roots in all threads that
2228 // are part of compiled frames
2229 static void compiled_frame_oops_do(OopClosure* f, CodeBlobClosure* cf);
2230
2231 static void convert_hcode_pointers();
2232 static void restore_hcode_pointers();
2233
2234 // Sweeper
2235 static void nmethods_do(CodeBlobClosure* cf);
2236
2237 // RedefineClasses support
2238 static void metadata_do(void f(Metadata*));
2239 static void metadata_handles_do(void f(Metadata*));
2240
2241 #ifdef ASSERT
2242 static bool is_vm_complete() { return _vm_complete; }
2243 #endif
2244
2245 // Verification
2246 static void verify();
2247 static void print_on(outputStream* st, bool print_stacks, bool internal_format, bool print_concurrent_locks);
2248 static void print(bool print_stacks, bool internal_format) {
2249 // this function is only used by debug.cpp
2250 print_on(tty, print_stacks, internal_format, false /* no concurrent lock printed */);
2251 }
2252 static void print_on_error(outputStream* st, Thread* current, char* buf, int buflen);
2253 static void print_on_error(Thread* this_thread, outputStream* st, Thread* current, char* buf,
2254 int buflen, bool* found_current);
2255 static void print_threads_compiling(outputStream* st, char* buf, int buflen);
2256
2257 // Get Java threads that are waiting to enter a monitor.
2258 static GrowableArray<JavaThread*>* get_pending_threads(ThreadsList * t_list,
2259 int count, address monitor);
2260
2261 // Get owning Java thread from the monitor's owner field.
2262 static JavaThread *owning_thread_from_monitor_owner(ThreadsList * t_list,
2263 address owner);
2264
2265 // Number of threads on the active threads list
2266 static int number_of_threads() { return _number_of_threads; }
2267 // Number of non-daemon threads on the active threads list
2268 static int number_of_non_daemon_threads() { return _number_of_non_daemon_threads; }
2269
2270 // Deoptimizes all frames tied to marked nmethods
2271 static void deoptimized_wrt_marked_nmethods();
2272 };
2273
2274
2275 // Thread iterator
2276 class ThreadClosure: public StackObj {
2277 public:
2278 virtual void do_thread(Thread* thread) = 0;
2279 };
2280
2281 class SignalHandlerMark: public StackObj {
2282 private:
2283 Thread* _thread;
2284 public:
2285 SignalHandlerMark(Thread* t) {
2286 _thread = t;
2287 if (_thread) _thread->enter_signal_handler();
2288 }
2289 ~SignalHandlerMark() {
2290 if (_thread) _thread->leave_signal_handler();
2291 _thread = NULL;
2292 }
2293 };
2294
2295
2296 #endif // SHARE_VM_RUNTIME_THREAD_HPP