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
61 class JvmtiThreadState;
62 class JvmtiGetLoadedClassesClosure;
63 class ThreadStatistics;
64 class ConcurrentLocksDump;
65 class ParkEvent;
66 class Parker;
67
68 class ciEnv;
69 class CompileThread;
70 class CompileLog;
71 class CompileTask;
72 class CompileQueue;
73 class CompilerCounters;
74 class vframeArray;
75
76 class DeoptResourceMark;
77 class jvmtiDeferredLocalVariableSet;
78
79 class GCTaskQueue;
80 class ThreadClosure;
81 class IdealGraphPrinter;
82
83 class Metadata;
84 template <class T, MEMFLAGS F> class ChunkedList;
85 typedef ChunkedList<Metadata*, mtInternal> MetadataOnStackBuffer;
86
87 DEBUG_ONLY(class ResourceMark;)
88
89 class WorkerThread;
90
91 // Class hierarchy
92 // - Thread
93 // - NamedThread
94 // - VMThread
95 // - ConcurrentGCThread
96 // - WorkerThread
97 // - GangWorker
98 // - GCTaskThread
99 // - JavaThread
100 // - various subclasses eg CompilerThread, ServiceThread
101 // - WatcherThread
102
103 class Thread: public ThreadShadow {
104 friend class VMStructs;
105 friend class JVMCIVMStructs;
106 private:
107
108 #ifndef USE_LIBRARY_BASED_TLS_ONLY
109 // Current thread is maintained as a thread-local variable
110 static THREAD_LOCAL_DECL Thread* _thr_current;
111 #endif
112
113 // Exception handling
114 // (Note: _pending_exception and friends are in ThreadShadow)
115 //oop _pending_exception; // pending exception for current thread
116 // const char* _exception_file; // file information for exception (debugging only)
117 // int _exception_line; // line information for exception (debugging only)
118 protected:
119 // Support for forcing alignment of thread objects for biased locking
120 void* _real_malloc_address;
121 public:
122 void* operator new(size_t size) throw() { return allocate(size, true); }
123 void* operator new(size_t size, const std::nothrow_t& nothrow_constant) throw() {
124 return allocate(size, false); }
125 void operator delete(void* p);
126
127 protected:
128 static void* allocate(size_t size, bool throw_excpt, MEMFLAGS flags = mtThread);
129 private:
130
131 // ***************************************************************
132 // Suspend and resume support
133 // ***************************************************************
134 //
135 // VM suspend/resume no longer exists - it was once used for various
136 // things including safepoints but was deprecated and finally removed
137 // in Java 7. Because VM suspension was considered "internal" Java-level
138 // suspension was considered "external", and this legacy naming scheme
139 // remains.
140 //
141 // External suspend/resume requests come from JVM_SuspendThread,
142 // JVM_ResumeThread, JVMTI SuspendThread, and finally JVMTI
143 // ResumeThread. External
144 // suspend requests cause _external_suspend to be set and external
145 // resume requests cause _external_suspend to be cleared.
146 // External suspend requests do not nest on top of other external
147 // suspend requests. The higher level APIs reject suspend requests
148 // for already suspended threads.
149 //
150 // The external_suspend
151 // flag is checked by has_special_runtime_exit_condition() and java thread
152 // will self-suspend when handle_special_runtime_exit_condition() is
153 // called. Most uses of the _thread_blocked state in JavaThreads are
154 // considered the same as being externally suspended; if the blocking
155 // condition lifts, the JavaThread will self-suspend. Other places
156 // where VM checks for external_suspend include:
157 // + mutex granting (do not enter monitors when thread is suspended)
158 // + state transitions from _thread_in_native
159 //
160 // In general, java_suspend() does not wait for an external suspend
161 // request to complete. When it returns, the only guarantee is that
162 // the _external_suspend field is true.
163 //
164 // wait_for_ext_suspend_completion() is used to wait for an external
165 // suspend request to complete. External suspend requests are usually
166 // followed by some other interface call that requires the thread to
167 // be quiescent, e.g., GetCallTrace(). By moving the "wait time" into
168 // the interface that requires quiescence, we give the JavaThread a
169 // chance to self-suspend before we need it to be quiescent. This
170 // improves overall suspend/query performance.
171 //
172 // _suspend_flags controls the behavior of java_ suspend/resume.
173 // It must be set under the protection of SR_lock. Read from the flag is
174 // OK without SR_lock as long as the value is only used as a hint.
175 // (e.g., check _external_suspend first without lock and then recheck
176 // inside SR_lock and finish the suspension)
177 //
178 // _suspend_flags is also overloaded for other "special conditions" so
179 // that a single check indicates whether any special action is needed
180 // eg. for async exceptions.
181 // -------------------------------------------------------------------
182 // Notes:
183 // 1. The suspend/resume logic no longer uses ThreadState in OSThread
184 // but we still update its value to keep other part of the system (mainly
185 // JVMTI) happy. ThreadState is legacy code (see notes in
186 // osThread.hpp).
187 //
188 // 2. It would be more natural if set_external_suspend() is private and
189 // part of java_suspend(), but that probably would affect the suspend/query
190 // performance. Need more investigation on this.
191
192 // suspend/resume lock: used for self-suspend
193 Monitor* _SR_lock;
194
195 protected:
196 enum SuspendFlags {
197 // NOTE: avoid using the sign-bit as cc generates different test code
198 // when the sign-bit is used, and sometimes incorrectly - see CR 6398077
199
200 _external_suspend = 0x20000000U, // thread is asked to self suspend
201 _ext_suspended = 0x40000000U, // thread has self-suspended
202 _deopt_suspend = 0x10000000U, // thread needs to self suspend for deopt
203
204 _has_async_exception = 0x00000001U, // there is a pending async exception
205 _critical_native_unlock = 0x00000002U, // Must call back to unlock JNI critical lock
206
207 _trace_flag = 0x00000004U // call tracing backend
208 };
209
210 // various suspension related flags - atomically updated
211 // overloaded for async exception checking in check_special_condition_for_native_trans.
212 volatile uint32_t _suspend_flags;
213
214 private:
215 int _num_nested_signal;
216
217 DEBUG_ONLY(bool _suspendible_thread;)
218
219 public:
220 void enter_signal_handler() { _num_nested_signal++; }
221 void leave_signal_handler() { _num_nested_signal--; }
222 bool is_inside_signal_handler() const { return _num_nested_signal > 0; }
223
224 #ifdef ASSERT
225 void set_suspendible_thread() {
226 _suspendible_thread = true;
227 }
228
229 void clear_suspendible_thread() {
230 _suspendible_thread = false;
231 }
232
233 bool is_suspendible_thread() { return _suspendible_thread; }
234 #endif
235
236 private:
237 // Active_handles points to a block of handles
238 JNIHandleBlock* _active_handles;
239
240 // One-element thread local free list
241 JNIHandleBlock* _free_handle_block;
242
243 // Point to the last handle mark
244 HandleMark* _last_handle_mark;
245
246 // The parity of the last strong_roots iteration in which this thread was
247 // claimed as a task.
248 int _oops_do_parity;
249
250 public:
251 void set_last_handle_mark(HandleMark* mark) { _last_handle_mark = mark; }
252 HandleMark* last_handle_mark() const { return _last_handle_mark; }
253 private:
254
255 // debug support for checking if code does allow safepoints or not
256 // GC points in the VM can happen because of allocation, invoking a VM operation, or blocking on
257 // mutex, or blocking on an object synchronizer (Java locking).
258 // If !allow_safepoint(), then an assertion failure will happen in any of the above cases
259 // If !allow_allocation(), then an assertion failure will happen during allocation
260 // (Hence, !allow_safepoint() => !allow_allocation()).
261 //
262 // The two classes NoSafepointVerifier and No_Allocation_Verifier are used to set these counters.
263 //
264 NOT_PRODUCT(int _allow_safepoint_count;) // If 0, thread allow a safepoint to happen
265 debug_only(int _allow_allocation_count;) // If 0, the thread is allowed to allocate oops.
266
267 // Used by SkipGCALot class.
268 NOT_PRODUCT(bool _skip_gcalot;) // Should we elide gc-a-lot?
269
270 friend class NoAllocVerifier;
271 friend class NoSafepointVerifier;
272 friend class PauseNoSafepointVerifier;
273 friend class GCLocker;
274
275 volatile void* _polling_page; // Thread local polling page
276
277 ThreadLocalAllocBuffer _tlab; // Thread-local eden
278 jlong _allocated_bytes; // Cumulative number of bytes allocated on
279 // the Java heap
280
281 mutable TRACE_DATA _trace_data; // Thread-local data for tracing
282
283 ThreadExt _ext;
284
285 int _vm_operation_started_count; // VM_Operation support
286 int _vm_operation_completed_count; // VM_Operation support
287
288 ObjectMonitor* _current_pending_monitor; // ObjectMonitor this thread
289 // is waiting to lock
290 bool _current_pending_monitor_is_from_java; // locking is from Java code
291
292 // ObjectMonitor on which this thread called Object.wait()
293 ObjectMonitor* _current_waiting_monitor;
294
295 // Private thread-local objectmonitor list - a simple cache organized as a SLL.
296 public:
297 ObjectMonitor* omFreeList;
298 int omFreeCount; // length of omFreeList
299 int omFreeProvision; // reload chunk size
300 ObjectMonitor* omInUseList; // SLL to track monitors in circulation
301 int omInUseCount; // length of omInUseList
302
303 #ifdef ASSERT
304 private:
305 bool _visited_for_critical_count;
306
307 public:
308 void set_visited_for_critical_count(bool z) { _visited_for_critical_count = z; }
309 bool was_visited_for_critical_count() const { return _visited_for_critical_count; }
310 #endif
311
312 public:
313 enum {
314 is_definitely_current_thread = true
315 };
316
317 // Constructor
318 Thread();
319 virtual ~Thread();
320
321 // Manage Thread::current()
322 void initialize_thread_current();
323 void clear_thread_current(); // TLS cleanup needed before threads terminate
324
325 public:
326 // thread entry point
327 virtual void run();
328
329 // Testers
330 virtual bool is_VM_thread() const { return false; }
331 virtual bool is_Java_thread() const { return false; }
332 virtual bool is_Compiler_thread() const { return false; }
333 virtual bool is_Code_cache_sweeper_thread() const { return false; }
334 virtual bool is_hidden_from_external_view() const { return false; }
335 virtual bool is_jvmti_agent_thread() const { return false; }
336 // True iff the thread can perform GC operations at a safepoint.
337 // Generally will be true only of VM thread and parallel GC WorkGang
338 // threads.
339 virtual bool is_GC_task_thread() const { return false; }
340 virtual bool is_Watcher_thread() const { return false; }
341 virtual bool is_ConcurrentGC_thread() const { return false; }
342 virtual bool is_Named_thread() const { return false; }
343 virtual bool is_Worker_thread() const { return false; }
344
345 // Can this thread make Java upcalls
346 virtual bool can_call_java() const { return false; }
347
348 // Casts
349 virtual WorkerThread* as_Worker_thread() const { return NULL; }
350
351 virtual char* name() const { return (char*)"Unknown thread"; }
352
353 // Returns the current thread (ASSERTS if NULL)
354 static inline Thread* current();
355 // Returns the current thread, or NULL if not attached
356 static inline Thread* current_or_null();
357 // Returns the current thread, or NULL if not attached, and is
358 // safe for use from signal-handlers
359 static inline Thread* current_or_null_safe();
360
361 // Common thread operations
362 static void set_priority(Thread* thread, ThreadPriority priority);
363 static ThreadPriority get_priority(const Thread* const thread);
364 static void start(Thread* thread);
365 static void interrupt(Thread* thr);
366 static bool is_interrupted(Thread* thr, bool clear_interrupted);
367
368 void set_native_thread_name(const char *name) {
369 assert(Thread::current() == this, "set_native_thread_name can only be called on the current thread");
370 os::set_native_thread_name(name);
371 }
372
373 ObjectMonitor** omInUseList_addr() { return (ObjectMonitor **)&omInUseList; }
374 Monitor* SR_lock() const { return _SR_lock; }
375
376 bool has_async_exception() const { return (_suspend_flags & _has_async_exception) != 0; }
377
378 inline void set_suspend_flag(SuspendFlags f);
379 inline void clear_suspend_flag(SuspendFlags f);
380
381 inline void set_has_async_exception();
382 inline void clear_has_async_exception();
383
384 bool do_critical_native_unlock() const { return (_suspend_flags & _critical_native_unlock) != 0; }
385
386 inline void set_critical_native_unlock();
387 inline void clear_critical_native_unlock();
388
389 inline void set_trace_flag();
390 inline void clear_trace_flag();
391
392 // Support for Unhandled Oop detection
393 // Add the field for both, fastdebug and debug, builds to keep
394 // Thread's fields layout the same.
395 // Note: CHECK_UNHANDLED_OOPS is defined only for fastdebug build.
396 #ifdef CHECK_UNHANDLED_OOPS
397 private:
398 UnhandledOops* _unhandled_oops;
399 #elif defined(ASSERT)
400 private:
401 void* _unhandled_oops;
402 #endif
403 #ifdef CHECK_UNHANDLED_OOPS
404 public:
405 UnhandledOops* unhandled_oops() { return _unhandled_oops; }
406 // Mark oop safe for gc. It may be stack allocated but won't move.
407 void allow_unhandled_oop(oop *op) {
408 if (CheckUnhandledOops) unhandled_oops()->allow_unhandled_oop(op);
409 }
410 // Clear oops at safepoint so crashes point to unhandled oop violator
411 void clear_unhandled_oops() {
412 if (CheckUnhandledOops) unhandled_oops()->clear_unhandled_oops();
413 }
414 #endif // CHECK_UNHANDLED_OOPS
415
416 public:
417 #ifndef PRODUCT
418 bool skip_gcalot() { return _skip_gcalot; }
419 void set_skip_gcalot(bool v) { _skip_gcalot = v; }
420 #endif
421
422 // Installs a pending exception to be inserted later
423 static void send_async_exception(oop thread_oop, oop java_throwable);
424
425 // Resource area
426 ResourceArea* resource_area() const { return _resource_area; }
427 void set_resource_area(ResourceArea* area) { _resource_area = area; }
428
429 OSThread* osthread() const { return _osthread; }
430 void set_osthread(OSThread* thread) { _osthread = thread; }
431
432 // JNI handle support
433 JNIHandleBlock* active_handles() const { return _active_handles; }
434 void set_active_handles(JNIHandleBlock* block) { _active_handles = block; }
435 JNIHandleBlock* free_handle_block() const { return _free_handle_block; }
436 void set_free_handle_block(JNIHandleBlock* block) { _free_handle_block = block; }
437
438 // Internal handle support
439 HandleArea* handle_area() const { return _handle_area; }
440 void set_handle_area(HandleArea* area) { _handle_area = area; }
441
442 GrowableArray<Metadata*>* metadata_handles() const { return _metadata_handles; }
443 void set_metadata_handles(GrowableArray<Metadata*>* handles){ _metadata_handles = handles; }
444
445 // Thread-Local Allocation Buffer (TLAB) support
446 ThreadLocalAllocBuffer& tlab() { return _tlab; }
447 void initialize_tlab() {
448 if (UseTLAB) {
449 tlab().initialize();
450 }
451 }
452
453 jlong allocated_bytes() { return _allocated_bytes; }
454 void set_allocated_bytes(jlong value) { _allocated_bytes = value; }
455 void incr_allocated_bytes(jlong size) { _allocated_bytes += size; }
456 inline jlong cooked_allocated_bytes();
457
458 TRACE_DEFINE_THREAD_TRACE_DATA_OFFSET;
459 TRACE_DATA* trace_data() const { return &_trace_data; }
460 bool is_trace_suspend() { return (_suspend_flags & _trace_flag) != 0; }
461
462 const ThreadExt& ext() const { return _ext; }
463 ThreadExt& ext() { return _ext; }
464
465 // VM operation support
466 int vm_operation_ticket() { return ++_vm_operation_started_count; }
467 int vm_operation_completed_count() { return _vm_operation_completed_count; }
468 void increment_vm_operation_completed_count() { _vm_operation_completed_count++; }
469
470 // For tracking the heavyweight monitor the thread is pending on.
471 ObjectMonitor* current_pending_monitor() {
472 return _current_pending_monitor;
473 }
474 void set_current_pending_monitor(ObjectMonitor* monitor) {
475 _current_pending_monitor = monitor;
476 }
477 void set_current_pending_monitor_is_from_java(bool from_java) {
478 _current_pending_monitor_is_from_java = from_java;
479 }
480 bool current_pending_monitor_is_from_java() {
481 return _current_pending_monitor_is_from_java;
482 }
483
484 // For tracking the ObjectMonitor on which this thread called Object.wait()
485 ObjectMonitor* current_waiting_monitor() {
486 return _current_waiting_monitor;
487 }
488 void set_current_waiting_monitor(ObjectMonitor* monitor) {
489 _current_waiting_monitor = monitor;
490 }
491
492 // GC support
493 // Apply "f->do_oop" to all root oops in "this".
494 // Used by JavaThread::oops_do.
495 // Apply "cf->do_code_blob" (if !NULL) to all code blobs active in frames
496 virtual void oops_do(OopClosure* f, CodeBlobClosure* cf);
497
498 // Handles the parallel case for the method below.
499 private:
500 bool claim_oops_do_par_case(int collection_parity);
501 public:
502 // Requires that "collection_parity" is that of the current roots
503 // iteration. If "is_par" is false, sets the parity of "this" to
504 // "collection_parity", and returns "true". If "is_par" is true,
505 // uses an atomic instruction to set the current threads parity to
506 // "collection_parity", if it is not already. Returns "true" iff the
507 // calling thread does the update, this indicates that the calling thread
508 // has claimed the thread's stack as a root groop in the current
509 // collection.
510 bool claim_oops_do(bool is_par, int collection_parity) {
511 if (!is_par) {
512 _oops_do_parity = collection_parity;
513 return true;
514 } else {
515 return claim_oops_do_par_case(collection_parity);
516 }
517 }
518
519 // jvmtiRedefineClasses support
520 void metadata_handles_do(void f(Metadata*));
521
522 // Used by fast lock support
523 virtual bool is_lock_owned(address adr) const;
524
525 // Check if address is in the stack of the thread (not just for locks).
526 // Warning: the method can only be used on the running thread
527 bool is_in_stack(address adr) const;
528 // Check if address is in the usable part of the stack (excludes protected
529 // guard pages)
530 bool is_in_usable_stack(address adr) const;
531
532 // Sets this thread as starting thread. Returns failure if thread
533 // creation fails due to lack of memory, too many threads etc.
534 bool set_as_starting_thread();
535
536 protected:
537 // OS data associated with the thread
538 OSThread* _osthread; // Platform-specific thread information
539
540 // Thread local resource area for temporary allocation within the VM
541 ResourceArea* _resource_area;
542
543 DEBUG_ONLY(ResourceMark* _current_resource_mark;)
544
545 // Thread local handle area for allocation of handles within the VM
546 HandleArea* _handle_area;
547 GrowableArray<Metadata*>* _metadata_handles;
548
549 // Support for stack overflow handling, get_thread, etc.
550 address _stack_base;
551 size_t _stack_size;
552 uintptr_t _self_raw_id; // used by get_thread (mutable)
553 int _lgrp_id;
554
555 volatile void** polling_page_addr() { return &_polling_page; }
556
557 public:
558 // Stack overflow support
559 address stack_base() const { assert(_stack_base != NULL,"Sanity check"); return _stack_base; }
560 void set_stack_base(address base) { _stack_base = base; }
561 size_t stack_size() const { return _stack_size; }
562 void set_stack_size(size_t size) { _stack_size = size; }
563 address stack_end() const { return stack_base() - stack_size(); }
564 void record_stack_base_and_size();
565
566 bool on_local_stack(address adr) const {
567 // QQQ this has knowledge of direction, ought to be a stack method
568 return (_stack_base >= adr && adr >= stack_end());
569 }
570
571 uintptr_t self_raw_id() { return _self_raw_id; }
572 void set_self_raw_id(uintptr_t value) { _self_raw_id = value; }
573
574 int lgrp_id() const { return _lgrp_id; }
575 void set_lgrp_id(int value) { _lgrp_id = value; }
576
577 // Printing
578 virtual void print_on(outputStream* st) const;
579 void print() const { print_on(tty); }
580 virtual void print_on_error(outputStream* st, char* buf, int buflen) const;
581 void print_value_on(outputStream* st) const;
582
583 // Debug-only code
584 #ifdef ASSERT
585 private:
586 // Deadlock detection support for Mutex locks. List of locks own by thread.
587 Monitor* _owned_locks;
588 // Mutex::set_owner_implementation is the only place where _owned_locks is modified,
589 // thus the friendship
590 friend class Mutex;
591 friend class Monitor;
592
593 public:
594 void print_owned_locks_on(outputStream* st) const;
595 void print_owned_locks() const { print_owned_locks_on(tty); }
596 Monitor* owned_locks() const { return _owned_locks; }
597 bool owns_locks() const { return owned_locks() != NULL; }
598 bool owns_locks_but_compiled_lock() const;
599 int oops_do_parity() const { return _oops_do_parity; }
600
601 // Deadlock detection
602 bool allow_allocation() { return _allow_allocation_count == 0; }
603 ResourceMark* current_resource_mark() { return _current_resource_mark; }
604 void set_current_resource_mark(ResourceMark* rm) { _current_resource_mark = rm; }
605 #endif
606
607 void check_for_valid_safepoint_state(bool potential_vm_operation) PRODUCT_RETURN;
608
609 private:
610 volatile int _jvmti_env_iteration_count;
611
612 public:
613 void entering_jvmti_env_iteration() { ++_jvmti_env_iteration_count; }
614 void leaving_jvmti_env_iteration() { --_jvmti_env_iteration_count; }
615 bool is_inside_jvmti_env_iteration() { return _jvmti_env_iteration_count > 0; }
616
617 // Code generation
618 static ByteSize exception_file_offset() { return byte_offset_of(Thread, _exception_file); }
619 static ByteSize exception_line_offset() { return byte_offset_of(Thread, _exception_line); }
620 static ByteSize active_handles_offset() { return byte_offset_of(Thread, _active_handles); }
621
622 static ByteSize stack_base_offset() { return byte_offset_of(Thread, _stack_base); }
623 static ByteSize stack_size_offset() { return byte_offset_of(Thread, _stack_size); }
624
625 static ByteSize polling_page_offset() { return byte_offset_of(Thread, _polling_page); }
626
627 #define TLAB_FIELD_OFFSET(name) \
628 static ByteSize tlab_##name##_offset() { return byte_offset_of(Thread, _tlab) + ThreadLocalAllocBuffer::name##_offset(); }
629
630 TLAB_FIELD_OFFSET(start)
631 TLAB_FIELD_OFFSET(end)
632 TLAB_FIELD_OFFSET(top)
633 TLAB_FIELD_OFFSET(pf_top)
634 TLAB_FIELD_OFFSET(size) // desired_size
635 TLAB_FIELD_OFFSET(refill_waste_limit)
636 TLAB_FIELD_OFFSET(number_of_refills)
637 TLAB_FIELD_OFFSET(fast_refill_waste)
638 TLAB_FIELD_OFFSET(slow_allocations)
639
640 #undef TLAB_FIELD_OFFSET
641
642 static ByteSize allocated_bytes_offset() { return byte_offset_of(Thread, _allocated_bytes); }
643
644 public:
645 volatile intptr_t _Stalled;
646 volatile int _TypeTag;
647 ParkEvent * _ParkEvent; // for synchronized()
648 ParkEvent * _SleepEvent; // for Thread.sleep
649 ParkEvent * _MutexEvent; // for native internal Mutex/Monitor
650 ParkEvent * _MuxEvent; // for low-level muxAcquire-muxRelease
651 int NativeSyncRecursion; // diagnostic
652
653 volatile int _OnTrap; // Resume-at IP delta
654 jint _hashStateW; // Marsaglia Shift-XOR thread-local RNG
655 jint _hashStateX; // thread-specific hashCode generator state
656 jint _hashStateY;
657 jint _hashStateZ;
658 void * _schedctl;
659
660
661 volatile jint rng[4]; // RNG for spin loop
662
663 // Low-level leaf-lock primitives used to implement synchronization
664 // and native monitor-mutex infrastructure.
665 // Not for general synchronization use.
666 static void SpinAcquire(volatile int * Lock, const char * Name);
667 static void SpinRelease(volatile int * Lock);
668 static void muxAcquire(volatile intptr_t * Lock, const char * Name);
669 static void muxAcquireW(volatile intptr_t * Lock, ParkEvent * ev);
670 static void muxRelease(volatile intptr_t * Lock);
671 };
672
673 // Inline implementation of Thread::current()
674 inline Thread* Thread::current() {
675 Thread* current = current_or_null();
676 assert(current != NULL, "Thread::current() called on detached thread");
677 return current;
678 }
679
680 inline Thread* Thread::current_or_null() {
681 #ifndef USE_LIBRARY_BASED_TLS_ONLY
682 return _thr_current;
683 #else
684 if (ThreadLocalStorage::is_initialized()) {
685 return ThreadLocalStorage::thread();
686 }
687 return NULL;
688 #endif
689 }
690
691 inline Thread* Thread::current_or_null_safe() {
692 if (ThreadLocalStorage::is_initialized()) {
693 return ThreadLocalStorage::thread();
694 }
695 return NULL;
696 }
697
698 // Name support for threads. non-JavaThread subclasses with multiple
699 // uniquely named instances should derive from this.
700 class NamedThread: public Thread {
701 friend class VMStructs;
702 enum {
703 max_name_len = 64
704 };
705 private:
706 char* _name;
707 // log JavaThread being processed by oops_do
708 JavaThread* _processed_thread;
709 uint _gc_id; // The current GC id when a thread takes part in GC
710
711 public:
712 NamedThread();
713 ~NamedThread();
714 // May only be called once per thread.
715 void set_name(const char* format, ...) ATTRIBUTE_PRINTF(2, 3);
716 void initialize_named_thread();
717 virtual bool is_Named_thread() const { return true; }
718 virtual char* name() const { return _name == NULL ? (char*)"Unknown Thread" : _name; }
719 JavaThread *processed_thread() { return _processed_thread; }
720 void set_processed_thread(JavaThread *thread) { _processed_thread = thread; }
721 virtual void print_on(outputStream* st) const;
722
723 void set_gc_id(uint gc_id) { _gc_id = gc_id; }
724 uint gc_id() { return _gc_id; }
725 };
726
727 // Worker threads are named and have an id of an assigned work.
728 class WorkerThread: public NamedThread {
729 private:
730 uint _id;
731 public:
732 WorkerThread() : _id(0) { }
733 virtual bool is_Worker_thread() const { return true; }
734
735 virtual WorkerThread* as_Worker_thread() const {
736 assert(is_Worker_thread(), "Dubious cast to WorkerThread*?");
737 return (WorkerThread*) this;
738 }
739
740 void set_id(uint work_id) { _id = work_id; }
741 uint id() const { return _id; }
742 };
743
744 // A single WatcherThread is used for simulating timer interrupts.
745 class WatcherThread: public Thread {
746 friend class VMStructs;
747 public:
748 virtual void run();
749
750 private:
751 static WatcherThread* _watcher_thread;
752
753 static bool _startable;
754 // volatile due to at least one lock-free read
755 volatile static bool _should_terminate;
756 public:
757 enum SomeConstants {
758 delay_interval = 10 // interrupt delay in milliseconds
759 };
760
761 // Constructor
762 WatcherThread();
763
764 // No destruction allowed
765 ~WatcherThread() {
766 guarantee(false, "WatcherThread deletion must fix the race with VM termination");
767 }
768
769 // Tester
770 bool is_Watcher_thread() const { return true; }
771
772 // Printing
773 char* name() const { return (char*)"VM Periodic Task Thread"; }
774 void print_on(outputStream* st) const;
775 void unpark();
776
777 // Returns the single instance of WatcherThread
778 static WatcherThread* watcher_thread() { return _watcher_thread; }
779
780 // Create and start the single instance of WatcherThread, or stop it on shutdown
781 static void start();
782 static void stop();
783 // Only allow start once the VM is sufficiently initialized
784 // Otherwise the first task to enroll will trigger the start
785 static void make_startable();
786 private:
787 int sleep() const;
788 };
789
790
791 class CompilerThread;
792
793 typedef void (*ThreadFunction)(JavaThread*, TRAPS);
794
795 class JavaThread: public Thread {
796 friend class VMStructs;
797 friend class JVMCIVMStructs;
798 friend class WhiteBox;
799 private:
800 JavaThread* _next; // The next thread in the Threads list
801 oop _threadObj; // The Java level thread object
802
803 #ifdef ASSERT
804 private:
805 int _java_call_counter;
806
807 public:
808 int java_call_counter() { return _java_call_counter; }
809 void inc_java_call_counter() { _java_call_counter++; }
810 void dec_java_call_counter() {
811 assert(_java_call_counter > 0, "Invalid nesting of JavaCallWrapper");
812 _java_call_counter--;
813 }
814 private: // restore original namespace restriction
815 #endif // ifdef ASSERT
816
817 #ifndef PRODUCT
818 public:
819 enum {
820 jump_ring_buffer_size = 16
821 };
822 private: // restore original namespace restriction
823 #endif
824
825 JavaFrameAnchor _anchor; // Encapsulation of current java frame and it state
826
827 ThreadFunction _entry_point;
828
829 JNIEnv _jni_environment;
830
831 // Deopt support
832 DeoptResourceMark* _deopt_mark; // Holds special ResourceMark for deoptimization
833
834 intptr_t* _must_deopt_id; // id of frame that needs to be deopted once we
835 // transition out of native
836 CompiledMethod* _deopt_nmethod; // CompiledMethod that is currently being deoptimized
837 vframeArray* _vframe_array_head; // Holds the heap of the active vframeArrays
838 vframeArray* _vframe_array_last; // Holds last vFrameArray we popped
839 // Because deoptimization is lazy we must save jvmti requests to set locals
840 // in compiled frames until we deoptimize and we have an interpreter frame.
841 // This holds the pointer to array (yeah like there might be more than one) of
842 // description of compiled vframes that have locals that need to be updated.
843 GrowableArray<jvmtiDeferredLocalVariableSet*>* _deferred_locals_updates;
844
845 // Handshake value for fixing 6243940. We need a place for the i2c
846 // adapter to store the callee Method*. This value is NEVER live
847 // across a gc point so it does NOT have to be gc'd
848 // The handshake is open ended since we can't be certain that it will
849 // be NULLed. This is because we rarely ever see the race and end up
850 // in handle_wrong_method which is the backend of the handshake. See
851 // code in i2c adapters and handle_wrong_method.
852
853 Method* _callee_target;
854
855 // Used to pass back results to the interpreter or generated code running Java code.
856 oop _vm_result; // oop result is GC-preserved
857 Metadata* _vm_result_2; // non-oop result
858
859 // See ReduceInitialCardMarks: this holds the precise space interval of
860 // the most recent slow path allocation for which compiled code has
861 // elided card-marks for performance along the fast-path.
862 MemRegion _deferred_card_mark;
863
864 MonitorChunk* _monitor_chunks; // Contains the off stack monitors
865 // allocated during deoptimization
866 // and by JNI_MonitorEnter/Exit
867
868 // Async. requests support
869 enum AsyncRequests {
870 _no_async_condition = 0,
871 _async_exception,
872 _async_unsafe_access_error
873 };
874 AsyncRequests _special_runtime_exit_condition; // Enum indicating pending async. request
875 oop _pending_async_exception;
876
877 // Safepoint support
878 public: // Expose _thread_state for SafeFetchInt()
879 volatile JavaThreadState _thread_state;
880 private:
881 ThreadSafepointState *_safepoint_state; // Holds information about a thread during a safepoint
882 address _saved_exception_pc; // Saved pc of instruction where last implicit exception happened
883
884 // JavaThread termination support
885 enum TerminatedTypes {
886 _not_terminated = 0xDEAD - 2,
887 _thread_exiting, // JavaThread::exit() has been called for this thread
888 _thread_terminated, // JavaThread is removed from thread list
889 _vm_exited // JavaThread is still executing native code, but VM is terminated
890 // only VM_Exit can set _vm_exited
891 };
892
893 // In general a JavaThread's _terminated field transitions as follows:
894 //
895 // _not_terminated => _thread_exiting => _thread_terminated
896 //
897 // _vm_exited is a special value to cover the case of a JavaThread
898 // executing native code after the VM itself is terminated.
899 volatile TerminatedTypes _terminated;
900 // suspend/resume support
901 volatile bool _suspend_equivalent; // Suspend equivalent condition
902 jint _in_deopt_handler; // count of deoptimization
903 // handlers thread is in
904 volatile bool _doing_unsafe_access; // Thread may fault due to unsafe access
905 bool _do_not_unlock_if_synchronized; // Do not unlock the receiver of a synchronized method (since it was
906 // never locked) when throwing an exception. Used by interpreter only.
907
908 // JNI attach states:
909 enum JNIAttachStates {
910 _not_attaching_via_jni = 1, // thread is not attaching via JNI
911 _attaching_via_jni, // thread is attaching via JNI
912 _attached_via_jni // thread has attached via JNI
913 };
914
915 // A regular JavaThread's _jni_attach_state is _not_attaching_via_jni.
916 // A native thread that is attaching via JNI starts with a value
917 // of _attaching_via_jni and transitions to _attached_via_jni.
918 volatile JNIAttachStates _jni_attach_state;
919
920 public:
921 // State of the stack guard pages for this thread.
922 enum StackGuardState {
923 stack_guard_unused, // not needed
924 stack_guard_reserved_disabled,
925 stack_guard_yellow_reserved_disabled,// disabled (temporarily) after stack overflow
926 stack_guard_enabled // enabled
927 };
928
929 private:
930
931 #if INCLUDE_JVMCI
932 // The _pending_* fields below are used to communicate extra information
933 // from an uncommon trap in JVMCI compiled code to the uncommon trap handler.
934
935 // Communicates the DeoptReason and DeoptAction of the uncommon trap
936 int _pending_deoptimization;
937
938 // Specifies whether the uncommon trap is to bci 0 of a synchronized method
939 // before the monitor has been acquired.
940 bool _pending_monitorenter;
941
942 // Specifies if the DeoptReason for the last uncommon trap was Reason_transfer_to_interpreter
943 bool _pending_transfer_to_interpreter;
944
945 // Guard for re-entrant call to JVMCIRuntime::adjust_comp_level
946 bool _adjusting_comp_level;
947
948 // An object that JVMCI compiled code can use to further describe and
949 // uniquely identify the speculative optimization guarded by the uncommon trap
950 oop _pending_failed_speculation;
951
952 // These fields are mutually exclusive in terms of live ranges.
953 union {
954 // Communicates the pc at which the most recent implicit exception occurred
955 // from the signal handler to a deoptimization stub.
956 address _implicit_exception_pc;
957
958 // Communicates an alternative call target to an i2c stub from a JavaCall .
959 address _alternate_call_target;
960 } _jvmci;
961
962 // Support for high precision, thread sensitive counters in JVMCI compiled code.
963 jlong* _jvmci_counters;
964
965 public:
966 static jlong* _jvmci_old_thread_counters;
967 static void collect_counters(typeArrayOop array);
968 private:
969 #endif // INCLUDE_JVMCI
970
971 StackGuardState _stack_guard_state;
972
973 // Precompute the limit of the stack as used in stack overflow checks.
974 // We load it from here to simplify the stack overflow check in assembly.
975 address _stack_overflow_limit;
976 address _reserved_stack_activation;
977
978 // Compiler exception handling (NOTE: The _exception_oop is *NOT* the same as _pending_exception. It is
979 // used to temp. parsing values into and out of the runtime system during exception handling for compiled
980 // code)
981 volatile oop _exception_oop; // Exception thrown in compiled code
982 volatile address _exception_pc; // PC where exception happened
983 volatile address _exception_handler_pc; // PC for handler of exception
984 volatile int _is_method_handle_return; // true (== 1) if the current exception PC is a MethodHandle call site.
985
986 private:
987 // support for JNI critical regions
988 jint _jni_active_critical; // count of entries into JNI critical region
989
990 // Checked JNI: function name requires exception check
991 char* _pending_jni_exception_check_fn;
992
993 // For deadlock detection.
994 int _depth_first_number;
995
996 // JVMTI PopFrame support
997 // This is set to popframe_pending to signal that top Java frame should be popped immediately
998 int _popframe_condition;
999
1000 // If reallocation of scalar replaced objects fails, we throw OOM
1001 // and during exception propagation, pop the top
1002 // _frames_to_pop_failed_realloc frames, the ones that reference
1003 // failed reallocations.
1004 int _frames_to_pop_failed_realloc;
1005
1006 #ifndef PRODUCT
1007 int _jmp_ring_index;
1008 struct {
1009 // We use intptr_t instead of address so debugger doesn't try and display strings
1010 intptr_t _target;
1011 intptr_t _instruction;
1012 const char* _file;
1013 int _line;
1014 } _jmp_ring[jump_ring_buffer_size];
1015 #endif // PRODUCT
1016
1017 #if INCLUDE_ALL_GCS
1018 // Support for G1 barriers
1019
1020 SATBMarkQueue _satb_mark_queue; // Thread-local log for SATB barrier.
1021 // Set of all such queues.
1022 static SATBMarkQueueSet _satb_mark_queue_set;
1023
1024 DirtyCardQueue _dirty_card_queue; // Thread-local log for dirty cards.
1025 // Set of all such queues.
1026 static DirtyCardQueueSet _dirty_card_queue_set;
1027
1028 void flush_barrier_queues();
1029 #endif // INCLUDE_ALL_GCS
1030
1031 friend class VMThread;
1032 friend class ThreadWaitTransition;
1033 friend class VM_Exit;
1034
1035 void initialize(); // Initialized the instance variables
1036
1037 public:
1038 // Constructor
1039 JavaThread(bool is_attaching_via_jni = false); // for main thread and JNI attached threads
1040 JavaThread(ThreadFunction entry_point, size_t stack_size = 0);
1041 ~JavaThread();
1042
1043 #ifdef ASSERT
1044 // verify this JavaThread hasn't be published in the Threads::list yet
1045 void verify_not_published();
1046 #endif
1047
1048 //JNI functiontable getter/setter for JVMTI jni function table interception API.
1049 void set_jni_functions(struct JNINativeInterface_* functionTable) {
1050 _jni_environment.functions = functionTable;
1051 }
1052 struct JNINativeInterface_* get_jni_functions() {
1053 return (struct JNINativeInterface_ *)_jni_environment.functions;
1054 }
1055
1056 // This function is called at thread creation to allow
1057 // platform specific thread variables to be initialized.
1058 void cache_global_variables();
1059
1060 // Executes Shutdown.shutdown()
1061 void invoke_shutdown_hooks();
1062
1063 // Cleanup on thread exit
1064 enum ExitType {
1065 normal_exit,
1066 jni_detach
1067 };
1068 void exit(bool destroy_vm, ExitType exit_type = normal_exit);
1069
1070 void cleanup_failed_attach_current_thread();
1071
1072 // Testers
1073 virtual bool is_Java_thread() const { return true; }
1074 virtual bool can_call_java() const { return true; }
1075
1076 // Thread chain operations
1077 JavaThread* next() const { return _next; }
1078 void set_next(JavaThread* p) { _next = p; }
1079
1080 // Thread oop. threadObj() can be NULL for initial JavaThread
1081 // (or for threads attached via JNI)
1082 oop threadObj() const { return _threadObj; }
1083 void set_threadObj(oop p) { _threadObj = p; }
1084
1085 ThreadPriority java_priority() const; // Read from threadObj()
1086
1087 // Prepare thread and add to priority queue. If a priority is
1088 // not specified, use the priority of the thread object. Threads_lock
1089 // must be held while this function is called.
1090 void prepare(jobject jni_thread, ThreadPriority prio=NoPriority);
1091 void prepare_ext();
1092
1093 void set_saved_exception_pc(address pc) { _saved_exception_pc = pc; }
1094 address saved_exception_pc() { return _saved_exception_pc; }
1095
1096
1097 ThreadFunction entry_point() const { return _entry_point; }
1098
1099 // Allocates a new Java level thread object for this thread. thread_name may be NULL.
1100 void allocate_threadObj(Handle thread_group, const char* thread_name, bool daemon, TRAPS);
1101
1102 // Last frame anchor routines
1103
1104 JavaFrameAnchor* frame_anchor(void) { return &_anchor; }
1105
1106 // last_Java_sp
1107 bool has_last_Java_frame() const { return _anchor.has_last_Java_frame(); }
1108 intptr_t* last_Java_sp() const { return _anchor.last_Java_sp(); }
1109
1110 // last_Java_pc
1111
1112 address last_Java_pc(void) { return _anchor.last_Java_pc(); }
1113
1114 // Safepoint support
1115 #if !(defined(PPC64) || defined(AARCH64))
1116 JavaThreadState thread_state() const { return _thread_state; }
1117 void set_thread_state(JavaThreadState s) { _thread_state = s; }
1118 #else
1119 // Use membars when accessing volatile _thread_state. See
1120 // Threads::create_vm() for size checks.
1121 inline JavaThreadState thread_state() const;
1122 inline void set_thread_state(JavaThreadState s);
1123 #endif
1124 ThreadSafepointState *safepoint_state() const { return _safepoint_state; }
1125 void set_safepoint_state(ThreadSafepointState *state) { _safepoint_state = state; }
1126 bool is_at_poll_safepoint() { return _safepoint_state->is_at_poll_safepoint(); }
1127
1128 // thread has called JavaThread::exit() or is terminated
1129 bool is_exiting() { return _terminated == _thread_exiting || is_terminated(); }
1130 // thread is terminated (no longer on the threads list); we compare
1131 // against the two non-terminated values so that a freed JavaThread
1132 // will also be considered terminated.
1133 bool is_terminated() { return _terminated != _not_terminated && _terminated != _thread_exiting; }
1134 void set_terminated(TerminatedTypes t) { _terminated = t; }
1135 // special for Threads::remove() which is static:
1136 void set_terminated_value() { _terminated = _thread_terminated; }
1137 void block_if_vm_exited();
1138
1139 bool doing_unsafe_access() { return _doing_unsafe_access; }
1140 void set_doing_unsafe_access(bool val) { _doing_unsafe_access = val; }
1141
1142 bool do_not_unlock_if_synchronized() { return _do_not_unlock_if_synchronized; }
1143 void set_do_not_unlock_if_synchronized(bool val) { _do_not_unlock_if_synchronized = val; }
1144
1145 inline void set_polling_page(void* poll_value);
1146 inline volatile void* get_polling_page();
1147
1148 private:
1149 // Support for thread handshake operations
1150 HandshakeState _handshake;
1151 public:
1152 void set_handshake_operation(HandshakeOperation* op) {
1153 _handshake.set_operation(this, op);
1154 }
1155
1156 bool has_handshake() const {
1157 return _handshake.has_operation();
1158 }
1159
1160 void cancel_handshake() {
1161 _handshake.cancel(this);
1162 }
1163
1164 void handshake_process_by_self() {
1165 _handshake.process_by_self(this);
1166 }
1167
1168 void handshake_process_by_vmthread() {
1169 _handshake.process_by_vmthread(this);
1170 }
1171
1172 // Suspend/resume support for JavaThread
1173 private:
1174 inline void set_ext_suspended();
1175 inline void clear_ext_suspended();
1176
1177 public:
1178 void java_suspend();
1179 void java_resume();
1180 int java_suspend_self();
1181
1182 void check_and_wait_while_suspended() {
1183 assert(JavaThread::current() == this, "sanity check");
1184
1185 bool do_self_suspend;
1186 do {
1187 // were we externally suspended while we were waiting?
1188 do_self_suspend = handle_special_suspend_equivalent_condition();
1189 if (do_self_suspend) {
1190 // don't surprise the thread that suspended us by returning
1191 java_suspend_self();
1192 set_suspend_equivalent();
1193 }
1194 } while (do_self_suspend);
1195 }
1196 static void check_safepoint_and_suspend_for_native_trans(JavaThread *thread);
1197 // Check for async exception in addition to safepoint and suspend request.
1198 static void check_special_condition_for_native_trans(JavaThread *thread);
1199
1200 // Same as check_special_condition_for_native_trans but finishes the
1201 // transition into thread_in_Java mode so that it can potentially
1202 // block.
1203 static void check_special_condition_for_native_trans_and_transition(JavaThread *thread);
1204
1205 bool is_ext_suspend_completed(bool called_by_wait, int delay, uint32_t *bits);
1206 bool is_ext_suspend_completed_with_lock(uint32_t *bits) {
1207 MutexLockerEx ml(SR_lock(), Mutex::_no_safepoint_check_flag);
1208 // Warning: is_ext_suspend_completed() may temporarily drop the
1209 // SR_lock to allow the thread to reach a stable thread state if
1210 // it is currently in a transient thread state.
1211 return is_ext_suspend_completed(false /* !called_by_wait */,
1212 SuspendRetryDelay, bits);
1213 }
1214
1215 // We cannot allow wait_for_ext_suspend_completion() to run forever or
1216 // we could hang. SuspendRetryCount and SuspendRetryDelay are normally
1217 // passed as the count and delay parameters. Experiments with specific
1218 // calls to wait_for_ext_suspend_completion() can be done by passing
1219 // other values in the code. Experiments with all calls can be done
1220 // via the appropriate -XX options.
1221 bool wait_for_ext_suspend_completion(int count, int delay, uint32_t *bits);
1222
1223 inline void set_external_suspend();
1224 inline void clear_external_suspend();
1225
1226 inline void set_deopt_suspend();
1227 inline void clear_deopt_suspend();
1228 bool is_deopt_suspend() { return (_suspend_flags & _deopt_suspend) != 0; }
1229
1230 bool is_external_suspend() const {
1231 return (_suspend_flags & _external_suspend) != 0;
1232 }
1233 // Whenever a thread transitions from native to vm/java it must suspend
1234 // if external|deopt suspend is present.
1235 bool is_suspend_after_native() const {
1236 return (_suspend_flags & (_external_suspend | _deopt_suspend)) != 0;
1237 }
1238
1239 // external suspend request is completed
1240 bool is_ext_suspended() const {
1241 return (_suspend_flags & _ext_suspended) != 0;
1242 }
1243
1244 bool is_external_suspend_with_lock() const {
1245 MutexLockerEx ml(SR_lock(), Mutex::_no_safepoint_check_flag);
1246 return is_external_suspend();
1247 }
1248
1249 // Special method to handle a pending external suspend request
1250 // when a suspend equivalent condition lifts.
1251 bool handle_special_suspend_equivalent_condition() {
1252 assert(is_suspend_equivalent(),
1253 "should only be called in a suspend equivalence condition");
1254 MutexLockerEx ml(SR_lock(), Mutex::_no_safepoint_check_flag);
1255 bool ret = is_external_suspend();
1256 if (!ret) {
1257 // not about to self-suspend so clear suspend equivalence
1258 clear_suspend_equivalent();
1259 }
1260 // implied else:
1261 // We have a pending external suspend request so we leave the
1262 // suspend_equivalent flag set until java_suspend_self() sets
1263 // the ext_suspended flag and clears the suspend_equivalent
1264 // flag. This insures that wait_for_ext_suspend_completion()
1265 // will return consistent values.
1266 return ret;
1267 }
1268
1269 // utility methods to see if we are doing some kind of suspension
1270 bool is_being_ext_suspended() const {
1271 MutexLockerEx ml(SR_lock(), Mutex::_no_safepoint_check_flag);
1272 return is_ext_suspended() || is_external_suspend();
1273 }
1274
1275 bool is_suspend_equivalent() const { return _suspend_equivalent; }
1276
1277 void set_suspend_equivalent() { _suspend_equivalent = true; }
1278 void clear_suspend_equivalent() { _suspend_equivalent = false; }
1279
1280 // Thread.stop support
1281 void send_thread_stop(oop throwable);
1282 AsyncRequests clear_special_runtime_exit_condition() {
1283 AsyncRequests x = _special_runtime_exit_condition;
1284 _special_runtime_exit_condition = _no_async_condition;
1285 return x;
1286 }
1287
1288 // Are any async conditions present?
1289 bool has_async_condition() { return (_special_runtime_exit_condition != _no_async_condition); }
1290
1291 void check_and_handle_async_exceptions(bool check_unsafe_error = true);
1292
1293 // these next two are also used for self-suspension and async exception support
1294 void handle_special_runtime_exit_condition(bool check_asyncs = true);
1295
1296 // Return true if JavaThread has an asynchronous condition or
1297 // if external suspension is requested.
1298 bool has_special_runtime_exit_condition() {
1299 // Because we don't use is_external_suspend_with_lock
1300 // it is possible that we won't see an asynchronous external suspend
1301 // request that has just gotten started, i.e., SR_lock grabbed but
1302 // _external_suspend field change either not made yet or not visible
1303 // yet. However, this is okay because the request is asynchronous and
1304 // we will see the new flag value the next time through. It's also
1305 // possible that the external suspend request is dropped after
1306 // we have checked is_external_suspend(), we will recheck its value
1307 // under SR_lock in java_suspend_self().
1308 return (_special_runtime_exit_condition != _no_async_condition) ||
1309 is_external_suspend() || is_trace_suspend();
1310 }
1311
1312 void set_pending_unsafe_access_error() { _special_runtime_exit_condition = _async_unsafe_access_error; }
1313
1314 inline void set_pending_async_exception(oop e);
1315
1316 // Fast-locking support
1317 bool is_lock_owned(address adr) const;
1318
1319 // Accessors for vframe array top
1320 // The linked list of vframe arrays are sorted on sp. This means when we
1321 // unpack the head must contain the vframe array to unpack.
1322 void set_vframe_array_head(vframeArray* value) { _vframe_array_head = value; }
1323 vframeArray* vframe_array_head() const { return _vframe_array_head; }
1324
1325 // Side structure for deferring update of java frame locals until deopt occurs
1326 GrowableArray<jvmtiDeferredLocalVariableSet*>* deferred_locals() const { return _deferred_locals_updates; }
1327 void set_deferred_locals(GrowableArray<jvmtiDeferredLocalVariableSet *>* vf) { _deferred_locals_updates = vf; }
1328
1329 // These only really exist to make debugging deopt problems simpler
1330
1331 void set_vframe_array_last(vframeArray* value) { _vframe_array_last = value; }
1332 vframeArray* vframe_array_last() const { return _vframe_array_last; }
1333
1334 // The special resourceMark used during deoptimization
1335
1336 void set_deopt_mark(DeoptResourceMark* value) { _deopt_mark = value; }
1337 DeoptResourceMark* deopt_mark(void) { return _deopt_mark; }
1338
1339 intptr_t* must_deopt_id() { return _must_deopt_id; }
1340 void set_must_deopt_id(intptr_t* id) { _must_deopt_id = id; }
1341 void clear_must_deopt_id() { _must_deopt_id = NULL; }
1342
1343 void set_deopt_compiled_method(CompiledMethod* nm) { _deopt_nmethod = nm; }
1344 CompiledMethod* deopt_compiled_method() { return _deopt_nmethod; }
1345
1346 Method* callee_target() const { return _callee_target; }
1347 void set_callee_target (Method* x) { _callee_target = x; }
1348
1349 // Oop results of vm runtime calls
1350 oop vm_result() const { return _vm_result; }
1351 void set_vm_result (oop x) { _vm_result = x; }
1352
1353 Metadata* vm_result_2() const { return _vm_result_2; }
1354 void set_vm_result_2 (Metadata* x) { _vm_result_2 = x; }
1355
1356 MemRegion deferred_card_mark() const { return _deferred_card_mark; }
1357 void set_deferred_card_mark(MemRegion mr) { _deferred_card_mark = mr; }
1358
1359 #if INCLUDE_JVMCI
1360 int pending_deoptimization() const { return _pending_deoptimization; }
1361 oop pending_failed_speculation() const { return _pending_failed_speculation; }
1362 bool adjusting_comp_level() const { return _adjusting_comp_level; }
1363 void set_adjusting_comp_level(bool b) { _adjusting_comp_level = b; }
1364 bool has_pending_monitorenter() const { return _pending_monitorenter; }
1365 void set_pending_monitorenter(bool b) { _pending_monitorenter = b; }
1366 void set_pending_deoptimization(int reason) { _pending_deoptimization = reason; }
1367 void set_pending_failed_speculation(oop failed_speculation) { _pending_failed_speculation = failed_speculation; }
1368 void set_pending_transfer_to_interpreter(bool b) { _pending_transfer_to_interpreter = b; }
1369 void set_jvmci_alternate_call_target(address a) { assert(_jvmci._alternate_call_target == NULL, "must be"); _jvmci._alternate_call_target = a; }
1370 void set_jvmci_implicit_exception_pc(address a) { assert(_jvmci._implicit_exception_pc == NULL, "must be"); _jvmci._implicit_exception_pc = a; }
1371 #endif // INCLUDE_JVMCI
1372
1373 // Exception handling for compiled methods
1374 oop exception_oop() const { return _exception_oop; }
1375 address exception_pc() const { return _exception_pc; }
1376 address exception_handler_pc() const { return _exception_handler_pc; }
1377 bool is_method_handle_return() const { return _is_method_handle_return == 1; }
1378
1379 void set_exception_oop(oop o) { (void)const_cast<oop&>(_exception_oop = o); }
1380 void set_exception_pc(address a) { _exception_pc = a; }
1381 void set_exception_handler_pc(address a) { _exception_handler_pc = a; }
1382 void set_is_method_handle_return(bool value) { _is_method_handle_return = value ? 1 : 0; }
1383
1384 void clear_exception_oop_and_pc() {
1385 set_exception_oop(NULL);
1386 set_exception_pc(NULL);
1387 }
1388
1389 // Stack overflow support
1390 //
1391 // (small addresses)
1392 //
1393 // -- <-- stack_end() ---
1394 // | |
1395 // | red pages |
1396 // | |
1397 // -- <-- stack_red_zone_base() |
1398 // | |
1399 // | guard
1400 // | yellow pages zone
1401 // | |
1402 // | |
1403 // -- <-- stack_yellow_zone_base() |
1404 // | |
1405 // | |
1406 // | reserved pages |
1407 // | |
1408 // -- <-- stack_reserved_zone_base() --- ---
1409 // /|\ shadow <-- stack_overflow_limit() (somewhere in here)
1410 // | zone
1411 // \|/ size
1412 // some untouched memory ---
1413 //
1414 //
1415 // --
1416 // |
1417 // | shadow zone
1418 // |
1419 // --
1420 // x frame n
1421 // --
1422 // x frame n-1
1423 // x
1424 // --
1425 // ...
1426 //
1427 // --
1428 // x frame 0
1429 // -- <-- stack_base()
1430 //
1431 // (large addresses)
1432 //
1433
1434 private:
1435 // These values are derived from flags StackRedPages, StackYellowPages,
1436 // StackReservedPages and StackShadowPages. The zone size is determined
1437 // ergonomically if page_size > 4K.
1438 static size_t _stack_red_zone_size;
1439 static size_t _stack_yellow_zone_size;
1440 static size_t _stack_reserved_zone_size;
1441 static size_t _stack_shadow_zone_size;
1442 public:
1443 inline size_t stack_available(address cur_sp);
1444
1445 static size_t stack_red_zone_size() {
1446 assert(_stack_red_zone_size > 0, "Don't call this before the field is initialized.");
1447 return _stack_red_zone_size;
1448 }
1449 static void set_stack_red_zone_size(size_t s) {
1450 assert(is_aligned(s, os::vm_page_size()),
1451 "We can not protect if the red zone size is not page aligned.");
1452 assert(_stack_red_zone_size == 0, "This should be called only once.");
1453 _stack_red_zone_size = s;
1454 }
1455 address stack_red_zone_base() {
1456 return (address)(stack_end() + stack_red_zone_size());
1457 }
1458 bool in_stack_red_zone(address a) {
1459 return a <= stack_red_zone_base() && a >= stack_end();
1460 }
1461
1462 static size_t stack_yellow_zone_size() {
1463 assert(_stack_yellow_zone_size > 0, "Don't call this before the field is initialized.");
1464 return _stack_yellow_zone_size;
1465 }
1466 static void set_stack_yellow_zone_size(size_t s) {
1467 assert(is_aligned(s, os::vm_page_size()),
1468 "We can not protect if the yellow zone size is not page aligned.");
1469 assert(_stack_yellow_zone_size == 0, "This should be called only once.");
1470 _stack_yellow_zone_size = s;
1471 }
1472
1473 static size_t stack_reserved_zone_size() {
1474 // _stack_reserved_zone_size may be 0. This indicates the feature is off.
1475 return _stack_reserved_zone_size;
1476 }
1477 static void set_stack_reserved_zone_size(size_t s) {
1478 assert(is_aligned(s, os::vm_page_size()),
1479 "We can not protect if the reserved zone size is not page aligned.");
1480 assert(_stack_reserved_zone_size == 0, "This should be called only once.");
1481 _stack_reserved_zone_size = s;
1482 }
1483 address stack_reserved_zone_base() {
1484 return (address)(stack_end() +
1485 (stack_red_zone_size() + stack_yellow_zone_size() + stack_reserved_zone_size()));
1486 }
1487 bool in_stack_reserved_zone(address a) {
1488 return (a <= stack_reserved_zone_base()) &&
1489 (a >= (address)((intptr_t)stack_reserved_zone_base() - stack_reserved_zone_size()));
1490 }
1491
1492 static size_t stack_yellow_reserved_zone_size() {
1493 return _stack_yellow_zone_size + _stack_reserved_zone_size;
1494 }
1495 bool in_stack_yellow_reserved_zone(address a) {
1496 return (a <= stack_reserved_zone_base()) && (a >= stack_red_zone_base());
1497 }
1498
1499 // Size of red + yellow + reserved zones.
1500 static size_t stack_guard_zone_size() {
1501 return stack_red_zone_size() + stack_yellow_reserved_zone_size();
1502 }
1503
1504 static size_t stack_shadow_zone_size() {
1505 assert(_stack_shadow_zone_size > 0, "Don't call this before the field is initialized.");
1506 return _stack_shadow_zone_size;
1507 }
1508 static void set_stack_shadow_zone_size(size_t s) {
1509 // The shadow area is not allocated or protected, so
1510 // it needs not be page aligned.
1511 // But the stack bang currently assumes that it is a
1512 // multiple of page size. This guarantees that the bang
1513 // loop touches all pages in the shadow zone.
1514 // This can be guaranteed differently, as well. E.g., if
1515 // the page size is a multiple of 4K, banging in 4K steps
1516 // suffices to touch all pages. (Some pages are banged
1517 // several times, though.)
1518 assert(is_aligned(s, os::vm_page_size()),
1519 "Stack bang assumes multiple of page size.");
1520 assert(_stack_shadow_zone_size == 0, "This should be called only once.");
1521 _stack_shadow_zone_size = s;
1522 }
1523
1524 void create_stack_guard_pages();
1525 void remove_stack_guard_pages();
1526
1527 void enable_stack_reserved_zone();
1528 void disable_stack_reserved_zone();
1529 void enable_stack_yellow_reserved_zone();
1530 void disable_stack_yellow_reserved_zone();
1531 void enable_stack_red_zone();
1532 void disable_stack_red_zone();
1533
1534 inline bool stack_guard_zone_unused();
1535 inline bool stack_yellow_reserved_zone_disabled();
1536 inline bool stack_reserved_zone_disabled();
1537 inline bool stack_guards_enabled();
1538
1539 address reserved_stack_activation() const { return _reserved_stack_activation; }
1540 void set_reserved_stack_activation(address addr) {
1541 assert(_reserved_stack_activation == stack_base()
1542 || _reserved_stack_activation == NULL
1543 || addr == stack_base(), "Must not be set twice");
1544 _reserved_stack_activation = addr;
1545 }
1546
1547 // Attempt to reguard the stack after a stack overflow may have occurred.
1548 // Returns true if (a) guard pages are not needed on this thread, (b) the
1549 // pages are already guarded, or (c) the pages were successfully reguarded.
1550 // Returns false if there is not enough stack space to reguard the pages, in
1551 // which case the caller should unwind a frame and try again. The argument
1552 // should be the caller's (approximate) sp.
1553 bool reguard_stack(address cur_sp);
1554 // Similar to above but see if current stackpoint is out of the guard area
1555 // and reguard if possible.
1556 bool reguard_stack(void);
1557
1558 address stack_overflow_limit() { return _stack_overflow_limit; }
1559 void set_stack_overflow_limit() {
1560 _stack_overflow_limit =
1561 stack_end() + MAX2(JavaThread::stack_guard_zone_size(), JavaThread::stack_shadow_zone_size());
1562 }
1563
1564 // Misc. accessors/mutators
1565 void set_do_not_unlock(void) { _do_not_unlock_if_synchronized = true; }
1566 void clr_do_not_unlock(void) { _do_not_unlock_if_synchronized = false; }
1567 bool do_not_unlock(void) { return _do_not_unlock_if_synchronized; }
1568
1569 #ifndef PRODUCT
1570 void record_jump(address target, address instr, const char* file, int line);
1571 #endif // PRODUCT
1572
1573 // For assembly stub generation
1574 static ByteSize threadObj_offset() { return byte_offset_of(JavaThread, _threadObj); }
1575 #ifndef PRODUCT
1576 static ByteSize jmp_ring_index_offset() { return byte_offset_of(JavaThread, _jmp_ring_index); }
1577 static ByteSize jmp_ring_offset() { return byte_offset_of(JavaThread, _jmp_ring); }
1578 #endif // PRODUCT
1579 static ByteSize jni_environment_offset() { return byte_offset_of(JavaThread, _jni_environment); }
1580 static ByteSize pending_jni_exception_check_fn_offset() {
1581 return byte_offset_of(JavaThread, _pending_jni_exception_check_fn);
1582 }
1583 static ByteSize last_Java_sp_offset() {
1584 return byte_offset_of(JavaThread, _anchor) + JavaFrameAnchor::last_Java_sp_offset();
1585 }
1586 static ByteSize last_Java_pc_offset() {
1587 return byte_offset_of(JavaThread, _anchor) + JavaFrameAnchor::last_Java_pc_offset();
1588 }
1589 static ByteSize frame_anchor_offset() {
1590 return byte_offset_of(JavaThread, _anchor);
1591 }
1592 static ByteSize callee_target_offset() { return byte_offset_of(JavaThread, _callee_target); }
1593 static ByteSize vm_result_offset() { return byte_offset_of(JavaThread, _vm_result); }
1594 static ByteSize vm_result_2_offset() { return byte_offset_of(JavaThread, _vm_result_2); }
1595 static ByteSize thread_state_offset() { return byte_offset_of(JavaThread, _thread_state); }
1596 static ByteSize saved_exception_pc_offset() { return byte_offset_of(JavaThread, _saved_exception_pc); }
1597 static ByteSize osthread_offset() { return byte_offset_of(JavaThread, _osthread); }
1598 #if INCLUDE_JVMCI
1599 static ByteSize pending_deoptimization_offset() { return byte_offset_of(JavaThread, _pending_deoptimization); }
1600 static ByteSize pending_monitorenter_offset() { return byte_offset_of(JavaThread, _pending_monitorenter); }
1601 static ByteSize pending_failed_speculation_offset() { return byte_offset_of(JavaThread, _pending_failed_speculation); }
1602 static ByteSize jvmci_alternate_call_target_offset() { return byte_offset_of(JavaThread, _jvmci._alternate_call_target); }
1603 static ByteSize jvmci_implicit_exception_pc_offset() { return byte_offset_of(JavaThread, _jvmci._implicit_exception_pc); }
1604 static ByteSize jvmci_counters_offset() { return byte_offset_of(JavaThread, _jvmci_counters); }
1605 #endif // INCLUDE_JVMCI
1606 static ByteSize exception_oop_offset() { return byte_offset_of(JavaThread, _exception_oop); }
1607 static ByteSize exception_pc_offset() { return byte_offset_of(JavaThread, _exception_pc); }
1608 static ByteSize exception_handler_pc_offset() { return byte_offset_of(JavaThread, _exception_handler_pc); }
1609 static ByteSize stack_overflow_limit_offset() { return byte_offset_of(JavaThread, _stack_overflow_limit); }
1610 static ByteSize is_method_handle_return_offset() { return byte_offset_of(JavaThread, _is_method_handle_return); }
1611 static ByteSize stack_guard_state_offset() { return byte_offset_of(JavaThread, _stack_guard_state); }
1612 static ByteSize reserved_stack_activation_offset() { return byte_offset_of(JavaThread, _reserved_stack_activation); }
1613 static ByteSize suspend_flags_offset() { return byte_offset_of(JavaThread, _suspend_flags); }
1614
1615 static ByteSize do_not_unlock_if_synchronized_offset() { return byte_offset_of(JavaThread, _do_not_unlock_if_synchronized); }
1616 static ByteSize should_post_on_exceptions_flag_offset() {
1617 return byte_offset_of(JavaThread, _should_post_on_exceptions_flag);
1618 }
1619
1620 #if INCLUDE_ALL_GCS
1621 static ByteSize satb_mark_queue_offset() { return byte_offset_of(JavaThread, _satb_mark_queue); }
1622 static ByteSize dirty_card_queue_offset() { return byte_offset_of(JavaThread, _dirty_card_queue); }
1623 #endif // INCLUDE_ALL_GCS
1624
1625 // Returns the jni environment for this thread
1626 JNIEnv* jni_environment() { return &_jni_environment; }
1627
1628 static JavaThread* thread_from_jni_environment(JNIEnv* env) {
1629 JavaThread *thread_from_jni_env = (JavaThread*)((intptr_t)env - in_bytes(jni_environment_offset()));
1630 // Only return NULL if thread is off the thread list; starting to
1631 // exit should not return NULL.
1632 if (thread_from_jni_env->is_terminated()) {
1633 thread_from_jni_env->block_if_vm_exited();
1634 return NULL;
1635 } else {
1636 return thread_from_jni_env;
1637 }
1638 }
1639
1640 // JNI critical regions. These can nest.
1641 bool in_critical() { return _jni_active_critical > 0; }
1642 bool in_last_critical() { return _jni_active_critical == 1; }
1643 void enter_critical() {
1644 assert(Thread::current() == this ||
1645 (Thread::current()->is_VM_thread() &&
1646 SafepointSynchronize::is_synchronizing()),
1647 "this must be current thread or synchronizing");
1648 _jni_active_critical++;
1649 }
1650 void exit_critical() {
1651 assert(Thread::current() == this, "this must be current thread");
1652 _jni_active_critical--;
1653 assert(_jni_active_critical >= 0, "JNI critical nesting problem?");
1654 }
1655
1656 // Checked JNI: is the programmer required to check for exceptions, if so specify
1657 // which function name. Returning to a Java frame should implicitly clear the
1658 // pending check, this is done for Native->Java transitions (i.e. user JNI code).
1659 // VM->Java transistions are not cleared, it is expected that JNI code enclosed
1660 // within ThreadToNativeFromVM makes proper exception checks (i.e. VM internal).
1661 bool is_pending_jni_exception_check() const { return _pending_jni_exception_check_fn != NULL; }
1662 void clear_pending_jni_exception_check() { _pending_jni_exception_check_fn = NULL; }
1663 const char* get_pending_jni_exception_check() const { return _pending_jni_exception_check_fn; }
1664 void set_pending_jni_exception_check(const char* fn_name) { _pending_jni_exception_check_fn = (char*) fn_name; }
1665
1666 // For deadlock detection
1667 int depth_first_number() { return _depth_first_number; }
1668 void set_depth_first_number(int dfn) { _depth_first_number = dfn; }
1669
1670 private:
1671 void set_monitor_chunks(MonitorChunk* monitor_chunks) { _monitor_chunks = monitor_chunks; }
1672
1673 public:
1674 MonitorChunk* monitor_chunks() const { return _monitor_chunks; }
1675 void add_monitor_chunk(MonitorChunk* chunk);
1676 void remove_monitor_chunk(MonitorChunk* chunk);
1677 bool in_deopt_handler() const { return _in_deopt_handler > 0; }
1678 void inc_in_deopt_handler() { _in_deopt_handler++; }
1679 void dec_in_deopt_handler() {
1680 assert(_in_deopt_handler > 0, "mismatched deopt nesting");
1681 if (_in_deopt_handler > 0) { // robustness
1682 _in_deopt_handler--;
1683 }
1684 }
1685
1686 private:
1687 void set_entry_point(ThreadFunction entry_point) { _entry_point = entry_point; }
1688
1689 public:
1690
1691 // Frame iteration; calls the function f for all frames on the stack
1692 void frames_do(void f(frame*, const RegisterMap*));
1693
1694 // Memory operations
1695 void oops_do(OopClosure* f, CodeBlobClosure* cf);
1696
1697 // Sweeper operations
1698 virtual void nmethods_do(CodeBlobClosure* cf);
1699
1700 // RedefineClasses Support
1701 void metadata_do(void f(Metadata*));
1702
1703 // Misc. operations
1704 char* name() const { return (char*)get_thread_name(); }
1705 void print_on(outputStream* st) const;
1706 void print_value();
1707 void print_thread_state_on(outputStream*) const PRODUCT_RETURN;
1708 void print_thread_state() const PRODUCT_RETURN;
1709 void print_on_error(outputStream* st, char* buf, int buflen) const;
1710 void print_name_on_error(outputStream* st, char* buf, int buflen) const;
1711 void verify();
1712 const char* get_thread_name() const;
1713 private:
1714 // factor out low-level mechanics for use in both normal and error cases
1715 const char* get_thread_name_string(char* buf = NULL, int buflen = 0) const;
1716 public:
1717 const char* get_threadgroup_name() const;
1718 const char* get_parent_name() const;
1719
1720 // Accessing frames
1721 frame last_frame() {
1722 _anchor.make_walkable(this);
1723 return pd_last_frame();
1724 }
1725 javaVFrame* last_java_vframe(RegisterMap* reg_map);
1726
1727 // Returns method at 'depth' java or native frames down the stack
1728 // Used for security checks
1729 Klass* security_get_caller_class(int depth);
1730
1731 // Print stack trace in external format
1732 void print_stack_on(outputStream* st);
1733 void print_stack() { print_stack_on(tty); }
1734
1735 // Print stack traces in various internal formats
1736 void trace_stack() PRODUCT_RETURN;
1737 void trace_stack_from(vframe* start_vf) PRODUCT_RETURN;
1738 void trace_frames() PRODUCT_RETURN;
1739 void trace_oops() PRODUCT_RETURN;
1740
1741 // Print an annotated view of the stack frames
1742 void print_frame_layout(int depth = 0, bool validate_only = false) NOT_DEBUG_RETURN;
1743 void validate_frame_layout() {
1744 print_frame_layout(0, true);
1745 }
1746
1747 // Returns the number of stack frames on the stack
1748 int depth() const;
1749
1750 // Function for testing deoptimization
1751 void deoptimize();
1752 void make_zombies();
1753
1754 void deoptimized_wrt_marked_nmethods();
1755
1756 public:
1757 // Returns the running thread as a JavaThread
1758 static inline JavaThread* current();
1759
1760 // Returns the active Java thread. Do not use this if you know you are calling
1761 // from a JavaThread, as it's slower than JavaThread::current. If called from
1762 // the VMThread, it also returns the JavaThread that instigated the VMThread's
1763 // operation. You may not want that either.
1764 static JavaThread* active();
1765
1766 inline CompilerThread* as_CompilerThread();
1767
1768 public:
1769 virtual void run();
1770 void thread_main_inner();
1771
1772 private:
1773 // PRIVILEGED STACK
1774 PrivilegedElement* _privileged_stack_top;
1775 GrowableArray<oop>* _array_for_gc;
1776 public:
1777
1778 // Returns the privileged_stack information.
1779 PrivilegedElement* privileged_stack_top() const { return _privileged_stack_top; }
1780 void set_privileged_stack_top(PrivilegedElement *e) { _privileged_stack_top = e; }
1781 void register_array_for_gc(GrowableArray<oop>* array) { _array_for_gc = array; }
1782
1783 public:
1784 // Thread local information maintained by JVMTI.
1785 void set_jvmti_thread_state(JvmtiThreadState *value) { _jvmti_thread_state = value; }
1786 // A JvmtiThreadState is lazily allocated. This jvmti_thread_state()
1787 // getter is used to get this JavaThread's JvmtiThreadState if it has
1788 // one which means NULL can be returned. JvmtiThreadState::state_for()
1789 // is used to get the specified JavaThread's JvmtiThreadState if it has
1790 // one or it allocates a new JvmtiThreadState for the JavaThread and
1791 // returns it. JvmtiThreadState::state_for() will return NULL only if
1792 // the specified JavaThread is exiting.
1793 JvmtiThreadState *jvmti_thread_state() const { return _jvmti_thread_state; }
1794 static ByteSize jvmti_thread_state_offset() { return byte_offset_of(JavaThread, _jvmti_thread_state); }
1795 void set_jvmti_get_loaded_classes_closure(JvmtiGetLoadedClassesClosure* value) { _jvmti_get_loaded_classes_closure = value; }
1796 JvmtiGetLoadedClassesClosure* get_jvmti_get_loaded_classes_closure() const { return _jvmti_get_loaded_classes_closure; }
1797
1798 // JVMTI PopFrame support
1799 // Setting and clearing popframe_condition
1800 // All of these enumerated values are bits. popframe_pending
1801 // indicates that a PopFrame() has been requested and not yet been
1802 // completed. popframe_processing indicates that that PopFrame() is in
1803 // the process of being completed. popframe_force_deopt_reexecution_bit
1804 // indicates that special handling is required when returning to a
1805 // deoptimized caller.
1806 enum PopCondition {
1807 popframe_inactive = 0x00,
1808 popframe_pending_bit = 0x01,
1809 popframe_processing_bit = 0x02,
1810 popframe_force_deopt_reexecution_bit = 0x04
1811 };
1812 PopCondition popframe_condition() { return (PopCondition) _popframe_condition; }
1813 void set_popframe_condition(PopCondition c) { _popframe_condition = c; }
1814 void set_popframe_condition_bit(PopCondition c) { _popframe_condition |= c; }
1815 void clear_popframe_condition() { _popframe_condition = popframe_inactive; }
1816 static ByteSize popframe_condition_offset() { return byte_offset_of(JavaThread, _popframe_condition); }
1817 bool has_pending_popframe() { return (popframe_condition() & popframe_pending_bit) != 0; }
1818 bool popframe_forcing_deopt_reexecution() { return (popframe_condition() & popframe_force_deopt_reexecution_bit) != 0; }
1819 void clear_popframe_forcing_deopt_reexecution() { _popframe_condition &= ~popframe_force_deopt_reexecution_bit; }
1820 #ifdef CC_INTERP
1821 bool pop_frame_pending(void) { return ((_popframe_condition & popframe_pending_bit) != 0); }
1822 void clr_pop_frame_pending(void) { _popframe_condition = popframe_inactive; }
1823 bool pop_frame_in_process(void) { return ((_popframe_condition & popframe_processing_bit) != 0); }
1824 void set_pop_frame_in_process(void) { _popframe_condition |= popframe_processing_bit; }
1825 void clr_pop_frame_in_process(void) { _popframe_condition &= ~popframe_processing_bit; }
1826 #endif
1827
1828 int frames_to_pop_failed_realloc() const { return _frames_to_pop_failed_realloc; }
1829 void set_frames_to_pop_failed_realloc(int nb) { _frames_to_pop_failed_realloc = nb; }
1830 void dec_frames_to_pop_failed_realloc() { _frames_to_pop_failed_realloc--; }
1831
1832 private:
1833 // Saved incoming arguments to popped frame.
1834 // Used only when popped interpreted frame returns to deoptimized frame.
1835 void* _popframe_preserved_args;
1836 int _popframe_preserved_args_size;
1837
1838 public:
1839 void popframe_preserve_args(ByteSize size_in_bytes, void* start);
1840 void* popframe_preserved_args();
1841 ByteSize popframe_preserved_args_size();
1842 WordSize popframe_preserved_args_size_in_words();
1843 void popframe_free_preserved_args();
1844
1845
1846 private:
1847 JvmtiThreadState *_jvmti_thread_state;
1848 JvmtiGetLoadedClassesClosure* _jvmti_get_loaded_classes_closure;
1849
1850 // Used by the interpreter in fullspeed mode for frame pop, method
1851 // entry, method exit and single stepping support. This field is
1852 // only set to non-zero by the VM_EnterInterpOnlyMode VM operation.
1853 // It can be set to zero asynchronously (i.e., without a VM operation
1854 // or a lock) so we have to be very careful.
1855 int _interp_only_mode;
1856
1857 public:
1858 // used by the interpreter for fullspeed debugging support (see above)
1859 static ByteSize interp_only_mode_offset() { return byte_offset_of(JavaThread, _interp_only_mode); }
1860 bool is_interp_only_mode() { return (_interp_only_mode != 0); }
1861 int get_interp_only_mode() { return _interp_only_mode; }
1862 void increment_interp_only_mode() { ++_interp_only_mode; }
1863 void decrement_interp_only_mode() { --_interp_only_mode; }
1864
1865 // support for cached flag that indicates whether exceptions need to be posted for this thread
1866 // if this is false, we can avoid deoptimizing when events are thrown
1867 // this gets set to reflect whether jvmtiExport::post_exception_throw would actually do anything
1868 private:
1869 int _should_post_on_exceptions_flag;
1870
1871 public:
1872 int should_post_on_exceptions_flag() { return _should_post_on_exceptions_flag; }
1873 void set_should_post_on_exceptions_flag(int val) { _should_post_on_exceptions_flag = val; }
1874
1875 private:
1876 ThreadStatistics *_thread_stat;
1877
1878 public:
1879 ThreadStatistics* get_thread_stat() const { return _thread_stat; }
1880
1881 // Return a blocker object for which this thread is blocked parking.
1882 oop current_park_blocker();
1883
1884 private:
1885 static size_t _stack_size_at_create;
1886
1887 public:
1888 static inline size_t stack_size_at_create(void) {
1889 return _stack_size_at_create;
1890 }
1891 static inline void set_stack_size_at_create(size_t value) {
1892 _stack_size_at_create = value;
1893 }
1894
1895 #if INCLUDE_ALL_GCS
1896 // SATB marking queue support
1897 SATBMarkQueue& satb_mark_queue() { return _satb_mark_queue; }
1898 static SATBMarkQueueSet& satb_mark_queue_set() {
1899 return _satb_mark_queue_set;
1900 }
1901
1902 // Dirty card queue support
1903 DirtyCardQueue& dirty_card_queue() { return _dirty_card_queue; }
1904 static DirtyCardQueueSet& dirty_card_queue_set() {
1905 return _dirty_card_queue_set;
1906 }
1907 #endif // INCLUDE_ALL_GCS
1908
1909 // This method initializes the SATB and dirty card queues before a
1910 // JavaThread is added to the Java thread list. Right now, we don't
1911 // have to do anything to the dirty card queue (it should have been
1912 // activated when the thread was created), but we have to activate
1913 // the SATB queue if the thread is created while a marking cycle is
1914 // in progress. The activation / de-activation of the SATB queues at
1915 // the beginning / end of a marking cycle is done during safepoints
1916 // so we have to make sure this method is called outside one to be
1917 // able to safely read the active field of the SATB queue set. Right
1918 // now, it is called just before the thread is added to the Java
1919 // thread list in the Threads::add() method. That method is holding
1920 // the Threads_lock which ensures we are outside a safepoint. We
1921 // cannot do the obvious and set the active field of the SATB queue
1922 // when the thread is created given that, in some cases, safepoints
1923 // might happen between the JavaThread constructor being called and the
1924 // thread being added to the Java thread list (an example of this is
1925 // when the structure for the DestroyJavaVM thread is created).
1926 #if INCLUDE_ALL_GCS
1927 void initialize_queues();
1928 #else // INCLUDE_ALL_GCS
1929 void initialize_queues() { }
1930 #endif // INCLUDE_ALL_GCS
1931
1932 // Machine dependent stuff
1933 #include OS_CPU_HEADER(thread)
1934
1935 public:
1936 void set_blocked_on_compilation(bool value) {
1937 _blocked_on_compilation = value;
1938 }
1939
1940 bool blocked_on_compilation() {
1941 return _blocked_on_compilation;
1942 }
1943 protected:
1944 bool _blocked_on_compilation;
1945
1946
1947 // JSR166 per-thread parker
1948 private:
1949 Parker* _parker;
1950 public:
1951 Parker* parker() { return _parker; }
1952
1953 // Biased locking support
1954 private:
1955 GrowableArray<MonitorInfo*>* _cached_monitor_info;
1956 public:
1957 GrowableArray<MonitorInfo*>* cached_monitor_info() { return _cached_monitor_info; }
1958 void set_cached_monitor_info(GrowableArray<MonitorInfo*>* info) { _cached_monitor_info = info; }
1959
1960 // clearing/querying jni attach status
1961 bool is_attaching_via_jni() const { return _jni_attach_state == _attaching_via_jni; }
1962 bool has_attached_via_jni() const { return is_attaching_via_jni() || _jni_attach_state == _attached_via_jni; }
1963 inline void set_done_attaching_via_jni();
1964 };
1965
1966 // Inline implementation of JavaThread::current
1967 inline JavaThread* JavaThread::current() {
1968 Thread* thread = Thread::current();
1969 assert(thread->is_Java_thread(), "just checking");
1970 return (JavaThread*)thread;
1971 }
1972
1973 inline CompilerThread* JavaThread::as_CompilerThread() {
1974 assert(is_Compiler_thread(), "just checking");
1975 return (CompilerThread*)this;
1976 }
1977
1978 // Dedicated thread to sweep the code cache
1979 class CodeCacheSweeperThread : public JavaThread {
1980 CompiledMethod* _scanned_compiled_method; // nmethod being scanned by the sweeper
1981 public:
1982 CodeCacheSweeperThread();
1983 // Track the nmethod currently being scanned by the sweeper
1984 void set_scanned_compiled_method(CompiledMethod* cm) {
1985 assert(_scanned_compiled_method == NULL || cm == NULL, "should reset to NULL before writing a new value");
1986 _scanned_compiled_method = cm;
1987 }
1988
1989 // Hide sweeper thread from external view.
1990 bool is_hidden_from_external_view() const { return true; }
1991
1992 bool is_Code_cache_sweeper_thread() const { return true; }
1993
1994 // Prevent GC from unloading _scanned_compiled_method
1995 void oops_do(OopClosure* f, CodeBlobClosure* cf);
1996 void nmethods_do(CodeBlobClosure* cf);
1997 };
1998
1999 // A thread used for Compilation.
2000 class CompilerThread : public JavaThread {
2001 friend class VMStructs;
2002 private:
2003 CompilerCounters* _counters;
2004
2005 ciEnv* _env;
2006 CompileLog* _log;
2007 CompileTask* _task;
2008 CompileQueue* _queue;
2009 BufferBlob* _buffer_blob;
2010
2011 AbstractCompiler* _compiler;
2012
2013 public:
2014
2015 static CompilerThread* current();
2016
2017 CompilerThread(CompileQueue* queue, CompilerCounters* counters);
2018
2019 bool is_Compiler_thread() const { return true; }
2020
2021 virtual bool can_call_java() const;
2022
2023 // Hide native compiler threads from external view.
2024 bool is_hidden_from_external_view() const { return !can_call_java(); }
2025
2026 void set_compiler(AbstractCompiler* c) { _compiler = c; }
2027 AbstractCompiler* compiler() const { return _compiler; }
2028
2029 CompileQueue* queue() const { return _queue; }
2030 CompilerCounters* counters() const { return _counters; }
2031
2032 // Get/set the thread's compilation environment.
2033 ciEnv* env() { return _env; }
2034 void set_env(ciEnv* env) { _env = env; }
2035
2036 BufferBlob* get_buffer_blob() const { return _buffer_blob; }
2037 void set_buffer_blob(BufferBlob* b) { _buffer_blob = b; }
2038
2039 // Get/set the thread's logging information
2040 CompileLog* log() { return _log; }
2041 void init_log(CompileLog* log) {
2042 // Set once, for good.
2043 assert(_log == NULL, "set only once");
2044 _log = log;
2045 }
2046
2047 #ifndef PRODUCT
2048 private:
2049 IdealGraphPrinter *_ideal_graph_printer;
2050 public:
2051 IdealGraphPrinter *ideal_graph_printer() { return _ideal_graph_printer; }
2052 void set_ideal_graph_printer(IdealGraphPrinter *n) { _ideal_graph_printer = n; }
2053 #endif
2054
2055 // Get/set the thread's current task
2056 CompileTask* task() { return _task; }
2057 void set_task(CompileTask* task) { _task = task; }
2058 };
2059
2060 inline CompilerThread* CompilerThread::current() {
2061 return JavaThread::current()->as_CompilerThread();
2062 }
2063
2064 // The active thread queue. It also keeps track of the current used
2065 // thread priorities.
2066 class Threads: AllStatic {
2067 friend class VMStructs;
2068 private:
2069 static JavaThread* _thread_list;
2070 static int _number_of_threads;
2071 static int _number_of_non_daemon_threads;
2072 static int _return_code;
2073 static int _thread_claim_parity;
2074 #ifdef ASSERT
2075 static bool _vm_complete;
2076 #endif
2077
2078 static void initialize_java_lang_classes(JavaThread* main_thread, TRAPS);
2079 static void initialize_jsr292_core_classes(TRAPS);
2080 public:
2081 // Thread management
2082 // force_daemon is a concession to JNI, where we may need to add a
2083 // thread to the thread list before allocating its thread object
2084 static void add(JavaThread* p, bool force_daemon = false);
2085 static void remove(JavaThread* p);
2086 static bool includes(JavaThread* p);
2087 static JavaThread* first() { return _thread_list; }
2088 static void threads_do(ThreadClosure* tc);
2089 static void possibly_parallel_threads_do(bool is_par, ThreadClosure* tc);
2090
2091 // Initializes the vm and creates the vm thread
2092 static jint create_vm(JavaVMInitArgs* args, bool* canTryAgain);
2093 static void convert_vm_init_libraries_to_agents();
2094 static void create_vm_init_libraries();
2095 static void create_vm_init_agents();
2096 static void shutdown_vm_agents();
2097 static bool destroy_vm();
2098 // Supported VM versions via JNI
2099 // Includes JNI_VERSION_1_1
2100 static jboolean is_supported_jni_version_including_1_1(jint version);
2101 // Does not include JNI_VERSION_1_1
2102 static jboolean is_supported_jni_version(jint version);
2103
2104 // The "thread claim parity" provides a way for threads to be claimed
2105 // by parallel worker tasks.
2106 //
2107 // Each thread contains a a "parity" field. A task will claim the
2108 // thread only if its parity field is the same as the global parity,
2109 // which is updated by calling change_thread_claim_parity().
2110 //
2111 // For this to work change_thread_claim_parity() needs to be called
2112 // exactly once in sequential code before starting parallel tasks
2113 // that should claim threads.
2114 //
2115 // New threads get their parity set to 0 and change_thread_claim_parity()
2116 // never set the global parity to 0.
2117 static int thread_claim_parity() { return _thread_claim_parity; }
2118 static void change_thread_claim_parity();
2119 static void assert_all_threads_claimed() NOT_DEBUG_RETURN;
2120
2121 // Apply "f->do_oop" to all root oops in all threads.
2122 // This version may only be called by sequential code.
2123 static void oops_do(OopClosure* f, CodeBlobClosure* cf);
2124 // This version may be called by sequential or parallel code.
2125 static void possibly_parallel_oops_do(bool is_par, OopClosure* f, CodeBlobClosure* cf);
2126 // This creates a list of GCTasks, one per thread.
2127 static void create_thread_roots_tasks(GCTaskQueue* q);
2128 // This creates a list of GCTasks, one per thread, for marking objects.
2129 static void create_thread_roots_marking_tasks(GCTaskQueue* q);
2130
2131 // Apply "f->do_oop" to roots in all threads that
2132 // are part of compiled frames
2133 static void compiled_frame_oops_do(OopClosure* f, CodeBlobClosure* cf);
2134
2135 static void convert_hcode_pointers();
2136 static void restore_hcode_pointers();
2137
2138 // Sweeper
2139 static void nmethods_do(CodeBlobClosure* cf);
2140
2141 // RedefineClasses support
2142 static void metadata_do(void f(Metadata*));
2143 static void metadata_handles_do(void f(Metadata*));
2144
2145 #ifdef ASSERT
2146 static bool is_vm_complete() { return _vm_complete; }
2147 #endif
2148
2149 // Verification
2150 static void verify();
2151 static void print_on(outputStream* st, bool print_stacks, bool internal_format, bool print_concurrent_locks);
2152 static void print(bool print_stacks, bool internal_format) {
2153 // this function is only used by debug.cpp
2154 print_on(tty, print_stacks, internal_format, false /* no concurrent lock printed */);
2155 }
2156 static void print_on_error(outputStream* st, Thread* current, char* buf, int buflen);
2157 static void print_on_error(Thread* this_thread, outputStream* st, Thread* current, char* buf,
2158 int buflen, bool* found_current);
2159 static void print_threads_compiling(outputStream* st, char* buf, int buflen);
2160
2161 // Get Java threads that are waiting to enter a monitor. If doLock
2162 // is true, then Threads_lock is grabbed as needed. Otherwise, the
2163 // VM needs to be at a safepoint.
2164 static GrowableArray<JavaThread*>* get_pending_threads(int count,
2165 address monitor, bool doLock);
2166
2167 // Get owning Java thread from the monitor's owner field. If doLock
2168 // is true, then Threads_lock is grabbed as needed. Otherwise, the
2169 // VM needs to be at a safepoint.
2170 static JavaThread *owning_thread_from_monitor_owner(address owner,
2171 bool doLock);
2172
2173 // Number of threads on the active threads list
2174 static int number_of_threads() { return _number_of_threads; }
2175 // Number of non-daemon threads on the active threads list
2176 static int number_of_non_daemon_threads() { return _number_of_non_daemon_threads; }
2177
2178 // Deoptimizes all frames tied to marked nmethods
2179 static void deoptimized_wrt_marked_nmethods();
2180
2181 static JavaThread* find_java_thread_from_java_tid(jlong java_tid);
2182
2183 };
2184
2185
2186 // Thread iterator
2187 class ThreadClosure: public StackObj {
2188 public:
2189 virtual void do_thread(Thread* thread) = 0;
2190 };
2191
2192 class SignalHandlerMark: public StackObj {
2193 private:
2194 Thread* _thread;
2195 public:
2196 SignalHandlerMark(Thread* t) {
2197 _thread = t;
2198 if (_thread) _thread->enter_signal_handler();
2199 }
2200 ~SignalHandlerMark() {
2201 if (_thread) _thread->leave_signal_handler();
2202 _thread = NULL;
2203 }
2204 };
2205
2206
2207 #endif // SHARE_VM_RUNTIME_THREAD_HPP