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 "gc/shared/threadLocalAllocBuffer.hpp"
29 #include "memory/allocation.hpp"
30 #include "oops/oop.hpp"
31 #include "prims/jni.h"
32 #include "prims/jvmtiExport.hpp"
33 #include "runtime/frame.hpp"
34 #include "runtime/javaFrameAnchor.hpp"
35 #include "runtime/jniHandles.hpp"
36 #include "runtime/mutexLocker.hpp"
37 #include "runtime/os.hpp"
38 #include "runtime/osThread.hpp"
39 #include "runtime/park.hpp"
40 #include "runtime/safepoint.hpp"
41 #include "runtime/stubRoutines.hpp"
42 #include "runtime/threadLocalStorage.hpp"
43 #include "runtime/thread_ext.hpp"
44 #include "runtime/unhandledOops.hpp"
45 #include "trace/traceBackend.hpp"
46 #include "trace/traceMacros.hpp"
47 #include "utilities/align.hpp"
48 #include "utilities/exceptions.hpp"
49 #include "utilities/macros.hpp"
50 #if INCLUDE_ALL_GCS
51 #include "gc/g1/dirtyCardQueue.hpp"
52 #include "gc/g1/satbMarkQueue.hpp"
53 #endif // INCLUDE_ALL_GCS
54 #ifdef ZERO
55 # include "stack_zero.hpp"
56 #endif
57
58 class ThreadSafepointState;
59
60 class JvmtiThreadState;
61 class JvmtiGetLoadedClassesClosure;
62 class ThreadStatistics;
63 class ConcurrentLocksDump;
64 class ParkEvent;
65 class Parker;
66
67 class ciEnv;
68 class CompileThread;
69 class CompileLog;
70 class CompileTask;
71 class CompileQueue;
72 class CompilerCounters;
73 class vframeArray;
74
75 class DeoptResourceMark;
76 class jvmtiDeferredLocalVariableSet;
77
78 class GCTaskQueue;
79 class ThreadClosure;
80 class IdealGraphPrinter;
81
82 class Metadata;
83 template <class T, MEMFLAGS F> class ChunkedList;
84 typedef ChunkedList<Metadata*, mtInternal> MetadataOnStackBuffer;
85
86 DEBUG_ONLY(class ResourceMark;)
87
88 class WorkerThread;
89
90 // Class hierarchy
91 // - Thread
92 // - NamedThread
93 // - VMThread
94 // - ConcurrentGCThread
95 // - WorkerThread
96 // - GangWorker
97 // - GCTaskThread
98 // - JavaThread
99 // - various subclasses eg CompilerThread, ServiceThread
100 // - WatcherThread
101
102 class Thread: public ThreadShadow {
103 friend class VMStructs;
104 friend class JVMCIVMStructs;
105 private:
106
107 #ifndef USE_LIBRARY_BASED_TLS_ONLY
108 // Current thread is maintained as a thread-local variable
109 static THREAD_LOCAL_DECL Thread* _thr_current;
110 #endif
111
112 // Exception handling
113 // (Note: _pending_exception and friends are in ThreadShadow)
114 //oop _pending_exception; // pending exception for current thread
115 // const char* _exception_file; // file information for exception (debugging only)
116 // int _exception_line; // line information for exception (debugging only)
117 protected:
118 // Support for forcing alignment of thread objects for biased locking
119 void* _real_malloc_address;
120 public:
121 void* operator new(size_t size) throw() { return allocate(size, true); }
122 void* operator new(size_t size, const std::nothrow_t& nothrow_constant) throw() {
123 return allocate(size, false); }
124 void operator delete(void* p);
125
126 protected:
127 static void* allocate(size_t size, bool throw_excpt, MEMFLAGS flags = mtThread);
128 private:
129
130 // ***************************************************************
131 // Suspend and resume support
132 // ***************************************************************
133 //
134 // VM suspend/resume no longer exists - it was once used for various
135 // things including safepoints but was deprecated and finally removed
136 // in Java 7. Because VM suspension was considered "internal" Java-level
137 // suspension was considered "external", and this legacy naming scheme
138 // remains.
139 //
140 // External suspend/resume requests come from JVM_SuspendThread,
141 // JVM_ResumeThread, JVMTI SuspendThread, and finally JVMTI
142 // ResumeThread. External
143 // suspend requests cause _external_suspend to be set and external
144 // resume requests cause _external_suspend to be cleared.
145 // External suspend requests do not nest on top of other external
146 // suspend requests. The higher level APIs reject suspend requests
147 // for already suspended threads.
148 //
149 // The external_suspend
150 // flag is checked by has_special_runtime_exit_condition() and java thread
151 // will self-suspend when handle_special_runtime_exit_condition() is
152 // called. Most uses of the _thread_blocked state in JavaThreads are
153 // considered the same as being externally suspended; if the blocking
154 // condition lifts, the JavaThread will self-suspend. Other places
155 // where VM checks for external_suspend include:
156 // + mutex granting (do not enter monitors when thread is suspended)
157 // + state transitions from _thread_in_native
158 //
159 // In general, java_suspend() does not wait for an external suspend
160 // request to complete. When it returns, the only guarantee is that
161 // the _external_suspend field is true.
162 //
163 // wait_for_ext_suspend_completion() is used to wait for an external
164 // suspend request to complete. External suspend requests are usually
165 // followed by some other interface call that requires the thread to
166 // be quiescent, e.g., GetCallTrace(). By moving the "wait time" into
167 // the interface that requires quiescence, we give the JavaThread a
168 // chance to self-suspend before we need it to be quiescent. This
169 // improves overall suspend/query performance.
170 //
171 // _suspend_flags controls the behavior of java_ suspend/resume.
172 // It must be set under the protection of SR_lock. Read from the flag is
173 // OK without SR_lock as long as the value is only used as a hint.
174 // (e.g., check _external_suspend first without lock and then recheck
175 // inside SR_lock and finish the suspension)
176 //
177 // _suspend_flags is also overloaded for other "special conditions" so
178 // that a single check indicates whether any special action is needed
179 // eg. for async exceptions.
180 // -------------------------------------------------------------------
181 // Notes:
182 // 1. The suspend/resume logic no longer uses ThreadState in OSThread
183 // but we still update its value to keep other part of the system (mainly
184 // JVMTI) happy. ThreadState is legacy code (see notes in
185 // osThread.hpp).
186 //
187 // 2. It would be more natural if set_external_suspend() is private and
188 // part of java_suspend(), but that probably would affect the suspend/query
189 // performance. Need more investigation on this.
190
191 // suspend/resume lock: used for self-suspend
192 Monitor* _SR_lock;
193
194 protected:
195 enum SuspendFlags {
196 // NOTE: avoid using the sign-bit as cc generates different test code
197 // when the sign-bit is used, and sometimes incorrectly - see CR 6398077
198
199 _external_suspend = 0x20000000U, // thread is asked to self suspend
200 _ext_suspended = 0x40000000U, // thread has self-suspended
201 _deopt_suspend = 0x10000000U, // thread needs to self suspend for deopt
202
203 _has_async_exception = 0x00000001U, // there is a pending async exception
204 _critical_native_unlock = 0x00000002U, // Must call back to unlock JNI critical lock
205
206 _trace_flag = 0x00000004U // call tracing backend
207 };
208
209 // various suspension related flags - atomically updated
210 // overloaded for async exception checking in check_special_condition_for_native_trans.
211 volatile uint32_t _suspend_flags;
212
213 private:
214 int _num_nested_signal;
215
216 DEBUG_ONLY(bool _suspendible_thread;)
217
218 public:
219 void enter_signal_handler() { _num_nested_signal++; }
220 void leave_signal_handler() { _num_nested_signal--; }
221 bool is_inside_signal_handler() const { return _num_nested_signal > 0; }
222
223 #ifdef ASSERT
224 void set_suspendible_thread() {
225 _suspendible_thread = true;
226 }
227
228 void clear_suspendible_thread() {
229 _suspendible_thread = false;
230 }
231
232 bool is_suspendible_thread() { return _suspendible_thread; }
233 #endif
234
235 private:
236 // Active_handles points to a block of handles
237 JNIHandleBlock* _active_handles;
238
239 // One-element thread local free list
240 JNIHandleBlock* _free_handle_block;
241
242 // Point to the last handle mark
243 HandleMark* _last_handle_mark;
244
245 // The parity of the last strong_roots iteration in which this thread was
246 // claimed as a task.
247 jint _oops_do_parity;
248
249 public:
250 void set_last_handle_mark(HandleMark* mark) { _last_handle_mark = mark; }
251 HandleMark* last_handle_mark() const { return _last_handle_mark; }
252 private:
253
254 // debug support for checking if code does allow safepoints or not
255 // GC points in the VM can happen because of allocation, invoking a VM operation, or blocking on
256 // mutex, or blocking on an object synchronizer (Java locking).
257 // If !allow_safepoint(), then an assertion failure will happen in any of the above cases
258 // If !allow_allocation(), then an assertion failure will happen during allocation
259 // (Hence, !allow_safepoint() => !allow_allocation()).
260 //
261 // The two classes NoSafepointVerifier and No_Allocation_Verifier are used to set these counters.
262 //
263 NOT_PRODUCT(int _allow_safepoint_count;) // If 0, thread allow a safepoint to happen
264 debug_only(int _allow_allocation_count;) // If 0, the thread is allowed to allocate oops.
265
266 // Used by SkipGCALot class.
267 NOT_PRODUCT(bool _skip_gcalot;) // Should we elide gc-a-lot?
268
269 friend class NoAllocVerifier;
270 friend class NoSafepointVerifier;
271 friend class PauseNoSafepointVerifier;
272 friend class GCLocker;
273
274 ThreadLocalAllocBuffer _tlab; // Thread-local eden
275 jlong _allocated_bytes; // Cumulative number of bytes allocated on
276 // the Java heap
277
278 mutable TRACE_DATA _trace_data; // Thread-local data for tracing
279
280 ThreadExt _ext;
281
282 int _vm_operation_started_count; // VM_Operation support
283 int _vm_operation_completed_count; // VM_Operation support
284
285 ObjectMonitor* _current_pending_monitor; // ObjectMonitor this thread
286 // is waiting to lock
287 bool _current_pending_monitor_is_from_java; // locking is from Java code
288
289 // ObjectMonitor on which this thread called Object.wait()
290 ObjectMonitor* _current_waiting_monitor;
291
292 // Private thread-local objectmonitor list - a simple cache organized as a SLL.
293 public:
294 ObjectMonitor* omFreeList;
295 int omFreeCount; // length of omFreeList
296 int omFreeProvision; // reload chunk size
297 ObjectMonitor* omInUseList; // SLL to track monitors in circulation
298 int omInUseCount; // length of omInUseList
299
300 #ifdef ASSERT
301 private:
302 bool _visited_for_critical_count;
303
304 public:
305 void set_visited_for_critical_count(bool z) { _visited_for_critical_count = z; }
306 bool was_visited_for_critical_count() const { return _visited_for_critical_count; }
307 #endif
308
309 public:
310 enum {
311 is_definitely_current_thread = true
312 };
313
314 // Constructor
315 Thread();
316 virtual ~Thread();
317
318 // Manage Thread::current()
319 void initialize_thread_current();
320 void clear_thread_current(); // TLS cleanup needed before threads terminate
321
322 public:
323 // thread entry point
324 virtual void run();
325
326 // Testers
327 virtual bool is_VM_thread() const { return false; }
328 virtual bool is_Java_thread() const { return false; }
329 virtual bool is_Compiler_thread() const { return false; }
330 virtual bool is_Code_cache_sweeper_thread() const { return false; }
331 virtual bool is_hidden_from_external_view() const { return false; }
332 virtual bool is_jvmti_agent_thread() const { return false; }
333 // True iff the thread can perform GC operations at a safepoint.
334 // Generally will be true only of VM thread and parallel GC WorkGang
335 // threads.
336 virtual bool is_GC_task_thread() const { return false; }
337 virtual bool is_Watcher_thread() const { return false; }
338 virtual bool is_ConcurrentGC_thread() const { return false; }
339 virtual bool is_Named_thread() const { return false; }
340 virtual bool is_Worker_thread() const { return false; }
341
342 // Can this thread make Java upcalls
343 virtual bool can_call_java() const { return false; }
344
345 // Casts
346 virtual WorkerThread* as_Worker_thread() const { return NULL; }
347
348 virtual char* name() const { return (char*)"Unknown thread"; }
349
350 // Returns the current thread (ASSERTS if NULL)
351 static inline Thread* current();
352 // Returns the current thread, or NULL if not attached
353 static inline Thread* current_or_null();
354 // Returns the current thread, or NULL if not attached, and is
355 // safe for use from signal-handlers
356 static inline Thread* current_or_null_safe();
357
358 // Common thread operations
359 static void set_priority(Thread* thread, ThreadPriority priority);
360 static ThreadPriority get_priority(const Thread* const thread);
361 static void start(Thread* thread);
362 static void interrupt(Thread* thr);
363 static bool is_interrupted(Thread* thr, bool clear_interrupted);
364
365 void set_native_thread_name(const char *name) {
366 assert(Thread::current() == this, "set_native_thread_name can only be called on the current thread");
367 os::set_native_thread_name(name);
368 }
369
370 ObjectMonitor** omInUseList_addr() { return (ObjectMonitor **)&omInUseList; }
371 Monitor* SR_lock() const { return _SR_lock; }
372
373 bool has_async_exception() const { return (_suspend_flags & _has_async_exception) != 0; }
374
375 inline void set_suspend_flag(SuspendFlags f);
376 inline void clear_suspend_flag(SuspendFlags f);
377
378 inline void set_has_async_exception();
379 inline void clear_has_async_exception();
380
381 bool do_critical_native_unlock() const { return (_suspend_flags & _critical_native_unlock) != 0; }
382
383 inline void set_critical_native_unlock();
384 inline void clear_critical_native_unlock();
385
386 inline void set_trace_flag();
387 inline void clear_trace_flag();
388
389 // Support for Unhandled Oop detection
390 // Add the field for both, fastdebug and debug, builds to keep
391 // Thread's fields layout the same.
392 // Note: CHECK_UNHANDLED_OOPS is defined only for fastdebug build.
393 #ifdef CHECK_UNHANDLED_OOPS
394 private:
395 UnhandledOops* _unhandled_oops;
396 #elif defined(ASSERT)
397 private:
398 void* _unhandled_oops;
399 #endif
400 #ifdef CHECK_UNHANDLED_OOPS
401 public:
402 UnhandledOops* unhandled_oops() { return _unhandled_oops; }
403 // Mark oop safe for gc. It may be stack allocated but won't move.
404 void allow_unhandled_oop(oop *op) {
405 if (CheckUnhandledOops) unhandled_oops()->allow_unhandled_oop(op);
406 }
407 // Clear oops at safepoint so crashes point to unhandled oop violator
408 void clear_unhandled_oops() {
409 if (CheckUnhandledOops) unhandled_oops()->clear_unhandled_oops();
410 }
411 #endif // CHECK_UNHANDLED_OOPS
412
413 public:
414 #ifndef PRODUCT
415 bool skip_gcalot() { return _skip_gcalot; }
416 void set_skip_gcalot(bool v) { _skip_gcalot = v; }
417 #endif
418
419 // Installs a pending exception to be inserted later
420 static void send_async_exception(oop thread_oop, oop java_throwable);
421
422 // Resource area
423 ResourceArea* resource_area() const { return _resource_area; }
424 void set_resource_area(ResourceArea* area) { _resource_area = area; }
425
426 OSThread* osthread() const { return _osthread; }
427 void set_osthread(OSThread* thread) { _osthread = thread; }
428
429 // JNI handle support
430 JNIHandleBlock* active_handles() const { return _active_handles; }
431 void set_active_handles(JNIHandleBlock* block) { _active_handles = block; }
432 JNIHandleBlock* free_handle_block() const { return _free_handle_block; }
433 void set_free_handle_block(JNIHandleBlock* block) { _free_handle_block = block; }
434
435 // Internal handle support
436 HandleArea* handle_area() const { return _handle_area; }
437 void set_handle_area(HandleArea* area) { _handle_area = area; }
438
439 GrowableArray<Metadata*>* metadata_handles() const { return _metadata_handles; }
440 void set_metadata_handles(GrowableArray<Metadata*>* handles){ _metadata_handles = handles; }
441
442 // Thread-Local Allocation Buffer (TLAB) support
443 ThreadLocalAllocBuffer& tlab() { return _tlab; }
444 void initialize_tlab() {
445 if (UseTLAB) {
446 tlab().initialize();
447 }
448 }
449
450 jlong allocated_bytes() { return _allocated_bytes; }
451 void set_allocated_bytes(jlong value) { _allocated_bytes = value; }
452 void incr_allocated_bytes(jlong size) { _allocated_bytes += size; }
453 inline jlong cooked_allocated_bytes();
454
455 TRACE_DEFINE_THREAD_TRACE_DATA_OFFSET;
456 TRACE_DATA* trace_data() const { return &_trace_data; }
457 bool is_trace_suspend() { return (_suspend_flags & _trace_flag) != 0; }
458
459 const ThreadExt& ext() const { return _ext; }
460 ThreadExt& ext() { return _ext; }
461
462 // VM operation support
463 int vm_operation_ticket() { return ++_vm_operation_started_count; }
464 int vm_operation_completed_count() { return _vm_operation_completed_count; }
465 void increment_vm_operation_completed_count() { _vm_operation_completed_count++; }
466
467 // For tracking the heavyweight monitor the thread is pending on.
468 ObjectMonitor* current_pending_monitor() {
469 return _current_pending_monitor;
470 }
471 void set_current_pending_monitor(ObjectMonitor* monitor) {
472 _current_pending_monitor = monitor;
473 }
474 void set_current_pending_monitor_is_from_java(bool from_java) {
475 _current_pending_monitor_is_from_java = from_java;
476 }
477 bool current_pending_monitor_is_from_java() {
478 return _current_pending_monitor_is_from_java;
479 }
480
481 // For tracking the ObjectMonitor on which this thread called Object.wait()
482 ObjectMonitor* current_waiting_monitor() {
483 return _current_waiting_monitor;
484 }
485 void set_current_waiting_monitor(ObjectMonitor* monitor) {
486 _current_waiting_monitor = monitor;
487 }
488
489 // GC support
490 // Apply "f->do_oop" to all root oops in "this".
491 // Used by JavaThread::oops_do.
492 // Apply "cf->do_code_blob" (if !NULL) to all code blobs active in frames
493 virtual void oops_do(OopClosure* f, CodeBlobClosure* cf);
494
495 // Handles the parallel case for the method below.
496 private:
497 bool claim_oops_do_par_case(int collection_parity);
498 public:
499 // Requires that "collection_parity" is that of the current roots
500 // iteration. If "is_par" is false, sets the parity of "this" to
501 // "collection_parity", and returns "true". If "is_par" is true,
502 // uses an atomic instruction to set the current threads parity to
503 // "collection_parity", if it is not already. Returns "true" iff the
504 // calling thread does the update, this indicates that the calling thread
505 // has claimed the thread's stack as a root groop in the current
506 // collection.
507 bool claim_oops_do(bool is_par, int collection_parity) {
508 if (!is_par) {
509 _oops_do_parity = collection_parity;
510 return true;
511 } else {
512 return claim_oops_do_par_case(collection_parity);
513 }
514 }
515
516 // jvmtiRedefineClasses support
517 void metadata_handles_do(void f(Metadata*));
518
519 // Used by fast lock support
520 virtual bool is_lock_owned(address adr) const;
521
522 // Check if address is in the stack of the thread (not just for locks).
523 // Warning: the method can only be used on the running thread
524 bool is_in_stack(address adr) const;
525 // Check if address is in the usable part of the stack (excludes protected
526 // guard pages)
527 bool is_in_usable_stack(address adr) const;
528
529 // Sets this thread as starting thread. Returns failure if thread
530 // creation fails due to lack of memory, too many threads etc.
531 bool set_as_starting_thread();
532
533 protected:
534 // OS data associated with the thread
535 OSThread* _osthread; // Platform-specific thread information
536
537 // Thread local resource area for temporary allocation within the VM
538 ResourceArea* _resource_area;
539
540 DEBUG_ONLY(ResourceMark* _current_resource_mark;)
541
542 // Thread local handle area for allocation of handles within the VM
543 HandleArea* _handle_area;
544 GrowableArray<Metadata*>* _metadata_handles;
545
546 // Support for stack overflow handling, get_thread, etc.
547 address _stack_base;
548 size_t _stack_size;
549 uintptr_t _self_raw_id; // used by get_thread (mutable)
550 int _lgrp_id;
551
552 public:
553 // Stack overflow support
554 address stack_base() const { assert(_stack_base != NULL,"Sanity check"); return _stack_base; }
555 void set_stack_base(address base) { _stack_base = base; }
556 size_t stack_size() const { return _stack_size; }
557 void set_stack_size(size_t size) { _stack_size = size; }
558 address stack_end() const { return stack_base() - stack_size(); }
559 void record_stack_base_and_size();
560
561 bool on_local_stack(address adr) const {
562 // QQQ this has knowledge of direction, ought to be a stack method
563 return (_stack_base >= adr && adr >= stack_end());
564 }
565
566 uintptr_t self_raw_id() { return _self_raw_id; }
567 void set_self_raw_id(uintptr_t value) { _self_raw_id = value; }
568
569 int lgrp_id() const { return _lgrp_id; }
570 void set_lgrp_id(int value) { _lgrp_id = value; }
571
572 // Printing
573 virtual void print_on(outputStream* st) const;
574 void print() const { print_on(tty); }
575 virtual void print_on_error(outputStream* st, char* buf, int buflen) const;
576 void print_value_on(outputStream* st) const;
577
578 // Debug-only code
579 #ifdef ASSERT
580 private:
581 // Deadlock detection support for Mutex locks. List of locks own by thread.
582 Monitor* _owned_locks;
583 // Mutex::set_owner_implementation is the only place where _owned_locks is modified,
584 // thus the friendship
585 friend class Mutex;
586 friend class Monitor;
587
588 public:
589 void print_owned_locks_on(outputStream* st) const;
590 void print_owned_locks() const { print_owned_locks_on(tty); }
591 Monitor* owned_locks() const { return _owned_locks; }
592 bool owns_locks() const { return owned_locks() != NULL; }
593 bool owns_locks_but_compiled_lock() const;
594 int oops_do_parity() const { return _oops_do_parity; }
595
596 // Deadlock detection
597 bool allow_allocation() { return _allow_allocation_count == 0; }
598 ResourceMark* current_resource_mark() { return _current_resource_mark; }
599 void set_current_resource_mark(ResourceMark* rm) { _current_resource_mark = rm; }
600 #endif
601
602 void check_for_valid_safepoint_state(bool potential_vm_operation) PRODUCT_RETURN;
603
604 private:
605 volatile int _jvmti_env_iteration_count;
606
607 public:
608 void entering_jvmti_env_iteration() { ++_jvmti_env_iteration_count; }
609 void leaving_jvmti_env_iteration() { --_jvmti_env_iteration_count; }
610 bool is_inside_jvmti_env_iteration() { return _jvmti_env_iteration_count > 0; }
611
612 // Code generation
613 static ByteSize exception_file_offset() { return byte_offset_of(Thread, _exception_file); }
614 static ByteSize exception_line_offset() { return byte_offset_of(Thread, _exception_line); }
615 static ByteSize active_handles_offset() { return byte_offset_of(Thread, _active_handles); }
616
617 static ByteSize stack_base_offset() { return byte_offset_of(Thread, _stack_base); }
618 static ByteSize stack_size_offset() { return byte_offset_of(Thread, _stack_size); }
619
620 #define TLAB_FIELD_OFFSET(name) \
621 static ByteSize tlab_##name##_offset() { return byte_offset_of(Thread, _tlab) + ThreadLocalAllocBuffer::name##_offset(); }
622
623 TLAB_FIELD_OFFSET(start)
624 TLAB_FIELD_OFFSET(end)
625 TLAB_FIELD_OFFSET(actual_end)
626 TLAB_FIELD_OFFSET(top)
627 TLAB_FIELD_OFFSET(pf_top)
628 TLAB_FIELD_OFFSET(size) // desired_size
629 TLAB_FIELD_OFFSET(refill_waste_limit)
630 TLAB_FIELD_OFFSET(number_of_refills)
631 TLAB_FIELD_OFFSET(fast_refill_waste)
632 TLAB_FIELD_OFFSET(slow_allocations)
633
634 #undef TLAB_FIELD_OFFSET
635
636 static ByteSize allocated_bytes_offset() { return byte_offset_of(Thread, _allocated_bytes); }
637
638 public:
639 volatile intptr_t _Stalled;
640 volatile int _TypeTag;
641 ParkEvent * _ParkEvent; // for synchronized()
642 ParkEvent * _SleepEvent; // for Thread.sleep
643 ParkEvent * _MutexEvent; // for native internal Mutex/Monitor
644 ParkEvent * _MuxEvent; // for low-level muxAcquire-muxRelease
645 int NativeSyncRecursion; // diagnostic
646
647 volatile int _OnTrap; // Resume-at IP delta
648 jint _hashStateW; // Marsaglia Shift-XOR thread-local RNG
649 jint _hashStateX; // thread-specific hashCode generator state
650 jint _hashStateY;
651 jint _hashStateZ;
652 void * _schedctl;
653
654
655 volatile jint rng[4]; // RNG for spin loop
656
657 // Low-level leaf-lock primitives used to implement synchronization
658 // and native monitor-mutex infrastructure.
659 // Not for general synchronization use.
660 static void SpinAcquire(volatile int * Lock, const char * Name);
661 static void SpinRelease(volatile int * Lock);
662 static void muxAcquire(volatile intptr_t * Lock, const char * Name);
663 static void muxAcquireW(volatile intptr_t * Lock, ParkEvent * ev);
664 static void muxRelease(volatile intptr_t * Lock);
665 };
666
667 // Inline implementation of Thread::current()
668 inline Thread* Thread::current() {
669 Thread* current = current_or_null();
670 assert(current != NULL, "Thread::current() called on detached thread");
671 return current;
672 }
673
674 inline Thread* Thread::current_or_null() {
675 #ifndef USE_LIBRARY_BASED_TLS_ONLY
676 return _thr_current;
677 #else
678 if (ThreadLocalStorage::is_initialized()) {
679 return ThreadLocalStorage::thread();
680 }
681 return NULL;
682 #endif
683 }
684
685 inline Thread* Thread::current_or_null_safe() {
686 if (ThreadLocalStorage::is_initialized()) {
687 return ThreadLocalStorage::thread();
688 }
689 return NULL;
690 }
691
692 // Name support for threads. non-JavaThread subclasses with multiple
693 // uniquely named instances should derive from this.
694 class NamedThread: public Thread {
695 friend class VMStructs;
696 enum {
697 max_name_len = 64
698 };
699 private:
700 char* _name;
701 // log JavaThread being processed by oops_do
702 JavaThread* _processed_thread;
703 uint _gc_id; // The current GC id when a thread takes part in GC
704
705 public:
706 NamedThread();
707 ~NamedThread();
708 // May only be called once per thread.
709 void set_name(const char* format, ...) ATTRIBUTE_PRINTF(2, 3);
710 void initialize_named_thread();
711 virtual bool is_Named_thread() const { return true; }
712 virtual char* name() const { return _name == NULL ? (char*)"Unknown Thread" : _name; }
713 JavaThread *processed_thread() { return _processed_thread; }
714 void set_processed_thread(JavaThread *thread) { _processed_thread = thread; }
715 virtual void print_on(outputStream* st) const;
716
717 void set_gc_id(uint gc_id) { _gc_id = gc_id; }
718 uint gc_id() { return _gc_id; }
719 };
720
721 // Worker threads are named and have an id of an assigned work.
722 class WorkerThread: public NamedThread {
723 private:
724 uint _id;
725 public:
726 WorkerThread() : _id(0) { }
727 virtual bool is_Worker_thread() const { return true; }
728
729 virtual WorkerThread* as_Worker_thread() const {
730 assert(is_Worker_thread(), "Dubious cast to WorkerThread*?");
731 return (WorkerThread*) this;
732 }
733
734 void set_id(uint work_id) { _id = work_id; }
735 uint id() const { return _id; }
736 };
737
738 // A single WatcherThread is used for simulating timer interrupts.
739 class WatcherThread: public Thread {
740 friend class VMStructs;
741 public:
742 virtual void run();
743
744 private:
745 static WatcherThread* _watcher_thread;
746
747 static bool _startable;
748 // volatile due to at least one lock-free read
749 volatile static bool _should_terminate;
750 public:
751 enum SomeConstants {
752 delay_interval = 10 // interrupt delay in milliseconds
753 };
754
755 // Constructor
756 WatcherThread();
757
758 // No destruction allowed
759 ~WatcherThread() {
760 guarantee(false, "WatcherThread deletion must fix the race with VM termination");
761 }
762
763 // Tester
764 bool is_Watcher_thread() const { return true; }
765
766 // Printing
767 char* name() const { return (char*)"VM Periodic Task Thread"; }
768 void print_on(outputStream* st) const;
769 void unpark();
770
771 // Returns the single instance of WatcherThread
772 static WatcherThread* watcher_thread() { return _watcher_thread; }
773
774 // Create and start the single instance of WatcherThread, or stop it on shutdown
775 static void start();
776 static void stop();
777 // Only allow start once the VM is sufficiently initialized
778 // Otherwise the first task to enroll will trigger the start
779 static void make_startable();
780 private:
781 int sleep() const;
782 };
783
784
785 class CompilerThread;
786
787 typedef void (*ThreadFunction)(JavaThread*, TRAPS);
788
789 class JavaThread: public Thread {
790 friend class VMStructs;
791 friend class JVMCIVMStructs;
792 friend class WhiteBox;
793 private:
794 JavaThread* _next; // The next thread in the Threads list
795 oop _threadObj; // The Java level thread object
796
797 #ifdef ASSERT
798 private:
799 int _java_call_counter;
800
801 public:
802 int java_call_counter() { return _java_call_counter; }
803 void inc_java_call_counter() { _java_call_counter++; }
804 void dec_java_call_counter() {
805 assert(_java_call_counter > 0, "Invalid nesting of JavaCallWrapper");
806 _java_call_counter--;
807 }
808 private: // restore original namespace restriction
809 #endif // ifdef ASSERT
810
811 #ifndef PRODUCT
812 public:
813 enum {
814 jump_ring_buffer_size = 16
815 };
816 private: // restore original namespace restriction
817 #endif
818
819 JavaFrameAnchor _anchor; // Encapsulation of current java frame and it state
820
821 ThreadFunction _entry_point;
822
823 JNIEnv _jni_environment;
824
825 // Deopt support
826 DeoptResourceMark* _deopt_mark; // Holds special ResourceMark for deoptimization
827
828 intptr_t* _must_deopt_id; // id of frame that needs to be deopted once we
829 // transition out of native
830 CompiledMethod* _deopt_nmethod; // CompiledMethod that is currently being deoptimized
831 vframeArray* _vframe_array_head; // Holds the heap of the active vframeArrays
832 vframeArray* _vframe_array_last; // Holds last vFrameArray we popped
833 // Because deoptimization is lazy we must save jvmti requests to set locals
834 // in compiled frames until we deoptimize and we have an interpreter frame.
835 // This holds the pointer to array (yeah like there might be more than one) of
836 // description of compiled vframes that have locals that need to be updated.
837 GrowableArray<jvmtiDeferredLocalVariableSet*>* _deferred_locals_updates;
838
839 // Handshake value for fixing 6243940. We need a place for the i2c
840 // adapter to store the callee Method*. This value is NEVER live
841 // across a gc point so it does NOT have to be gc'd
842 // The handshake is open ended since we can't be certain that it will
843 // be NULLed. This is because we rarely ever see the race and end up
844 // in handle_wrong_method which is the backend of the handshake. See
845 // code in i2c adapters and handle_wrong_method.
846
847 Method* _callee_target;
848
849 // Used to pass back results to the interpreter or generated code running Java code.
850 oop _vm_result; // oop result is GC-preserved
851 Metadata* _vm_result_2; // non-oop result
852
853 // See ReduceInitialCardMarks: this holds the precise space interval of
854 // the most recent slow path allocation for which compiled code has
855 // elided card-marks for performance along the fast-path.
856 MemRegion _deferred_card_mark;
857
858 MonitorChunk* _monitor_chunks; // Contains the off stack monitors
859 // allocated during deoptimization
860 // and by JNI_MonitorEnter/Exit
861
862 // Async. requests support
863 enum AsyncRequests {
864 _no_async_condition = 0,
865 _async_exception,
866 _async_unsafe_access_error
867 };
868 AsyncRequests _special_runtime_exit_condition; // Enum indicating pending async. request
869 oop _pending_async_exception;
870
871 // Safepoint support
872 public: // Expose _thread_state for SafeFetchInt()
873 volatile JavaThreadState _thread_state;
874 private:
875 ThreadSafepointState *_safepoint_state; // Holds information about a thread during a safepoint
876 address _saved_exception_pc; // Saved pc of instruction where last implicit exception happened
877
878 // JavaThread termination support
879 enum TerminatedTypes {
880 _not_terminated = 0xDEAD - 2,
881 _thread_exiting, // JavaThread::exit() has been called for this thread
882 _thread_terminated, // JavaThread is removed from thread list
883 _vm_exited // JavaThread is still executing native code, but VM is terminated
884 // only VM_Exit can set _vm_exited
885 };
886
887 // In general a JavaThread's _terminated field transitions as follows:
888 //
889 // _not_terminated => _thread_exiting => _thread_terminated
890 //
891 // _vm_exited is a special value to cover the case of a JavaThread
892 // executing native code after the VM itself is terminated.
893 volatile TerminatedTypes _terminated;
894 // suspend/resume support
895 volatile bool _suspend_equivalent; // Suspend equivalent condition
896 jint _in_deopt_handler; // count of deoptimization
897 // handlers thread is in
898 volatile bool _doing_unsafe_access; // Thread may fault due to unsafe access
899 bool _do_not_unlock_if_synchronized; // Do not unlock the receiver of a synchronized method (since it was
900 // never locked) when throwing an exception. Used by interpreter only.
901
902 // JNI attach states:
903 enum JNIAttachStates {
904 _not_attaching_via_jni = 1, // thread is not attaching via JNI
905 _attaching_via_jni, // thread is attaching via JNI
906 _attached_via_jni // thread has attached via JNI
907 };
908
909 // A regular JavaThread's _jni_attach_state is _not_attaching_via_jni.
910 // A native thread that is attaching via JNI starts with a value
911 // of _attaching_via_jni and transitions to _attached_via_jni.
912 volatile JNIAttachStates _jni_attach_state;
913
914 public:
915 // State of the stack guard pages for this thread.
916 enum StackGuardState {
917 stack_guard_unused, // not needed
918 stack_guard_reserved_disabled,
919 stack_guard_yellow_reserved_disabled,// disabled (temporarily) after stack overflow
920 stack_guard_enabled // enabled
921 };
922
923 private:
924
925 #if INCLUDE_JVMCI
926 // The _pending_* fields below are used to communicate extra information
927 // from an uncommon trap in JVMCI compiled code to the uncommon trap handler.
928
929 // Communicates the DeoptReason and DeoptAction of the uncommon trap
930 int _pending_deoptimization;
931
932 // Specifies whether the uncommon trap is to bci 0 of a synchronized method
933 // before the monitor has been acquired.
934 bool _pending_monitorenter;
935
936 // Specifies if the DeoptReason for the last uncommon trap was Reason_transfer_to_interpreter
937 bool _pending_transfer_to_interpreter;
938
939 // Guard for re-entrant call to JVMCIRuntime::adjust_comp_level
940 bool _adjusting_comp_level;
941
942 // An object that JVMCI compiled code can use to further describe and
943 // uniquely identify the speculative optimization guarded by the uncommon trap
944 oop _pending_failed_speculation;
945
946 // These fields are mutually exclusive in terms of live ranges.
947 union {
948 // Communicates the pc at which the most recent implicit exception occurred
949 // from the signal handler to a deoptimization stub.
950 address _implicit_exception_pc;
951
952 // Communicates an alternative call target to an i2c stub from a JavaCall .
953 address _alternate_call_target;
954 } _jvmci;
955
956 // Support for high precision, thread sensitive counters in JVMCI compiled code.
957 jlong* _jvmci_counters;
958
959 public:
960 static jlong* _jvmci_old_thread_counters;
961 static void collect_counters(typeArrayOop array);
962 private:
963 #endif // INCLUDE_JVMCI
964
965 StackGuardState _stack_guard_state;
966
967 // Precompute the limit of the stack as used in stack overflow checks.
968 // We load it from here to simplify the stack overflow check in assembly.
969 address _stack_overflow_limit;
970 address _reserved_stack_activation;
971
972 // Compiler exception handling (NOTE: The _exception_oop is *NOT* the same as _pending_exception. It is
973 // used to temp. parsing values into and out of the runtime system during exception handling for compiled
974 // code)
975 volatile oop _exception_oop; // Exception thrown in compiled code
976 volatile address _exception_pc; // PC where exception happened
977 volatile address _exception_handler_pc; // PC for handler of exception
978 volatile int _is_method_handle_return; // true (== 1) if the current exception PC is a MethodHandle call site.
979
980 private:
981 // support for JNI critical regions
982 jint _jni_active_critical; // count of entries into JNI critical region
983
984 // Checked JNI: function name requires exception check
985 char* _pending_jni_exception_check_fn;
986
987 // For deadlock detection.
988 int _depth_first_number;
989
990 // JVMTI PopFrame support
991 // This is set to popframe_pending to signal that top Java frame should be popped immediately
992 int _popframe_condition;
993
994 // If reallocation of scalar replaced objects fails, we throw OOM
995 // and during exception propagation, pop the top
996 // _frames_to_pop_failed_realloc frames, the ones that reference
997 // failed reallocations.
998 int _frames_to_pop_failed_realloc;
999
1000 #ifndef PRODUCT
1001 int _jmp_ring_index;
1002 struct {
1003 // We use intptr_t instead of address so debugger doesn't try and display strings
1004 intptr_t _target;
1005 intptr_t _instruction;
1006 const char* _file;
1007 int _line;
1008 } _jmp_ring[jump_ring_buffer_size];
1009 #endif // PRODUCT
1010
1011 #if INCLUDE_ALL_GCS
1012 // Support for G1 barriers
1013
1014 SATBMarkQueue _satb_mark_queue; // Thread-local log for SATB barrier.
1015 // Set of all such queues.
1016 static SATBMarkQueueSet _satb_mark_queue_set;
1017
1018 DirtyCardQueue _dirty_card_queue; // Thread-local log for dirty cards.
1019 // Set of all such queues.
1020 static DirtyCardQueueSet _dirty_card_queue_set;
1021
1022 void flush_barrier_queues();
1023 #endif // INCLUDE_ALL_GCS
1024
1025 friend class VMThread;
1026 friend class ThreadWaitTransition;
1027 friend class VM_Exit;
1028
1029 void initialize(); // Initialized the instance variables
1030
1031 public:
1032 // Constructor
1033 JavaThread(bool is_attaching_via_jni = false); // for main thread and JNI attached threads
1034 JavaThread(ThreadFunction entry_point, size_t stack_size = 0);
1035 ~JavaThread();
1036
1037 #ifdef ASSERT
1038 // verify this JavaThread hasn't be published in the Threads::list yet
1039 void verify_not_published();
1040 #endif
1041
1042 //JNI functiontable getter/setter for JVMTI jni function table interception API.
1043 void set_jni_functions(struct JNINativeInterface_* functionTable) {
1044 _jni_environment.functions = functionTable;
1045 }
1046 struct JNINativeInterface_* get_jni_functions() {
1047 return (struct JNINativeInterface_ *)_jni_environment.functions;
1048 }
1049
1050 // This function is called at thread creation to allow
1051 // platform specific thread variables to be initialized.
1052 void cache_global_variables();
1053
1054 // Executes Shutdown.shutdown()
1055 void invoke_shutdown_hooks();
1056
1057 // Cleanup on thread exit
1058 enum ExitType {
1059 normal_exit,
1060 jni_detach
1061 };
1062 void exit(bool destroy_vm, ExitType exit_type = normal_exit);
1063
1064 void cleanup_failed_attach_current_thread();
1065
1066 // Testers
1067 virtual bool is_Java_thread() const { return true; }
1068 virtual bool can_call_java() const { return true; }
1069
1070 // Thread chain operations
1071 JavaThread* next() const { return _next; }
1072 void set_next(JavaThread* p) { _next = p; }
1073
1074 // Thread oop. threadObj() can be NULL for initial JavaThread
1075 // (or for threads attached via JNI)
1076 oop threadObj() const { return _threadObj; }
1077 void set_threadObj(oop p) { _threadObj = p; }
1078
1079 ThreadPriority java_priority() const; // Read from threadObj()
1080
1081 // Prepare thread and add to priority queue. If a priority is
1082 // not specified, use the priority of the thread object. Threads_lock
1083 // must be held while this function is called.
1084 void prepare(jobject jni_thread, ThreadPriority prio=NoPriority);
1085 void prepare_ext();
1086
1087 void set_saved_exception_pc(address pc) { _saved_exception_pc = pc; }
1088 address saved_exception_pc() { return _saved_exception_pc; }
1089
1090
1091 ThreadFunction entry_point() const { return _entry_point; }
1092
1093 // Allocates a new Java level thread object for this thread. thread_name may be NULL.
1094 void allocate_threadObj(Handle thread_group, const char* thread_name, bool daemon, TRAPS);
1095
1096 // Last frame anchor routines
1097
1098 JavaFrameAnchor* frame_anchor(void) { return &_anchor; }
1099
1100 // last_Java_sp
1101 bool has_last_Java_frame() const { return _anchor.has_last_Java_frame(); }
1102 intptr_t* last_Java_sp() const { return _anchor.last_Java_sp(); }
1103
1104 // last_Java_pc
1105
1106 address last_Java_pc(void) { return _anchor.last_Java_pc(); }
1107
1108 // Safepoint support
1109 #if !(defined(PPC64) || defined(AARCH64))
1110 JavaThreadState thread_state() const { return _thread_state; }
1111 void set_thread_state(JavaThreadState s) { _thread_state = s; }
1112 #else
1113 // Use membars when accessing volatile _thread_state. See
1114 // Threads::create_vm() for size checks.
1115 inline JavaThreadState thread_state() const;
1116 inline void set_thread_state(JavaThreadState s);
1117 #endif
1118 ThreadSafepointState *safepoint_state() const { return _safepoint_state; }
1119 void set_safepoint_state(ThreadSafepointState *state) { _safepoint_state = state; }
1120 bool is_at_poll_safepoint() { return _safepoint_state->is_at_poll_safepoint(); }
1121
1122 // thread has called JavaThread::exit() or is terminated
1123 bool is_exiting() { return _terminated == _thread_exiting || is_terminated(); }
1124 // thread is terminated (no longer on the threads list); we compare
1125 // against the two non-terminated values so that a freed JavaThread
1126 // will also be considered terminated.
1127 bool is_terminated() { return _terminated != _not_terminated && _terminated != _thread_exiting; }
1128 void set_terminated(TerminatedTypes t) { _terminated = t; }
1129 // special for Threads::remove() which is static:
1130 void set_terminated_value() { _terminated = _thread_terminated; }
1131 void block_if_vm_exited();
1132
1133 bool doing_unsafe_access() { return _doing_unsafe_access; }
1134 void set_doing_unsafe_access(bool val) { _doing_unsafe_access = val; }
1135
1136 bool do_not_unlock_if_synchronized() { return _do_not_unlock_if_synchronized; }
1137 void set_do_not_unlock_if_synchronized(bool val) { _do_not_unlock_if_synchronized = val; }
1138
1139 // Suspend/resume support for JavaThread
1140 private:
1141 inline void set_ext_suspended();
1142 inline void clear_ext_suspended();
1143
1144 public:
1145 void java_suspend();
1146 void java_resume();
1147 int java_suspend_self();
1148
1149 void check_and_wait_while_suspended() {
1150 assert(JavaThread::current() == this, "sanity check");
1151
1152 bool do_self_suspend;
1153 do {
1154 // were we externally suspended while we were waiting?
1155 do_self_suspend = handle_special_suspend_equivalent_condition();
1156 if (do_self_suspend) {
1157 // don't surprise the thread that suspended us by returning
1158 java_suspend_self();
1159 set_suspend_equivalent();
1160 }
1161 } while (do_self_suspend);
1162 }
1163 static void check_safepoint_and_suspend_for_native_trans(JavaThread *thread);
1164 // Check for async exception in addition to safepoint and suspend request.
1165 static void check_special_condition_for_native_trans(JavaThread *thread);
1166
1167 // Same as check_special_condition_for_native_trans but finishes the
1168 // transition into thread_in_Java mode so that it can potentially
1169 // block.
1170 static void check_special_condition_for_native_trans_and_transition(JavaThread *thread);
1171
1172 bool is_ext_suspend_completed(bool called_by_wait, int delay, uint32_t *bits);
1173 bool is_ext_suspend_completed_with_lock(uint32_t *bits) {
1174 MutexLockerEx ml(SR_lock(), Mutex::_no_safepoint_check_flag);
1175 // Warning: is_ext_suspend_completed() may temporarily drop the
1176 // SR_lock to allow the thread to reach a stable thread state if
1177 // it is currently in a transient thread state.
1178 return is_ext_suspend_completed(false /* !called_by_wait */,
1179 SuspendRetryDelay, bits);
1180 }
1181
1182 // We cannot allow wait_for_ext_suspend_completion() to run forever or
1183 // we could hang. SuspendRetryCount and SuspendRetryDelay are normally
1184 // passed as the count and delay parameters. Experiments with specific
1185 // calls to wait_for_ext_suspend_completion() can be done by passing
1186 // other values in the code. Experiments with all calls can be done
1187 // via the appropriate -XX options.
1188 bool wait_for_ext_suspend_completion(int count, int delay, uint32_t *bits);
1189
1190 inline void set_external_suspend();
1191 inline void clear_external_suspend();
1192
1193 inline void set_deopt_suspend();
1194 inline void clear_deopt_suspend();
1195 bool is_deopt_suspend() { return (_suspend_flags & _deopt_suspend) != 0; }
1196
1197 bool is_external_suspend() const {
1198 return (_suspend_flags & _external_suspend) != 0;
1199 }
1200 // Whenever a thread transitions from native to vm/java it must suspend
1201 // if external|deopt suspend is present.
1202 bool is_suspend_after_native() const {
1203 return (_suspend_flags & (_external_suspend | _deopt_suspend)) != 0;
1204 }
1205
1206 // external suspend request is completed
1207 bool is_ext_suspended() const {
1208 return (_suspend_flags & _ext_suspended) != 0;
1209 }
1210
1211 bool is_external_suspend_with_lock() const {
1212 MutexLockerEx ml(SR_lock(), Mutex::_no_safepoint_check_flag);
1213 return is_external_suspend();
1214 }
1215
1216 // Special method to handle a pending external suspend request
1217 // when a suspend equivalent condition lifts.
1218 bool handle_special_suspend_equivalent_condition() {
1219 assert(is_suspend_equivalent(),
1220 "should only be called in a suspend equivalence condition");
1221 MutexLockerEx ml(SR_lock(), Mutex::_no_safepoint_check_flag);
1222 bool ret = is_external_suspend();
1223 if (!ret) {
1224 // not about to self-suspend so clear suspend equivalence
1225 clear_suspend_equivalent();
1226 }
1227 // implied else:
1228 // We have a pending external suspend request so we leave the
1229 // suspend_equivalent flag set until java_suspend_self() sets
1230 // the ext_suspended flag and clears the suspend_equivalent
1231 // flag. This insures that wait_for_ext_suspend_completion()
1232 // will return consistent values.
1233 return ret;
1234 }
1235
1236 // utility methods to see if we are doing some kind of suspension
1237 bool is_being_ext_suspended() const {
1238 MutexLockerEx ml(SR_lock(), Mutex::_no_safepoint_check_flag);
1239 return is_ext_suspended() || is_external_suspend();
1240 }
1241
1242 bool is_suspend_equivalent() const { return _suspend_equivalent; }
1243
1244 void set_suspend_equivalent() { _suspend_equivalent = true; }
1245 void clear_suspend_equivalent() { _suspend_equivalent = false; }
1246
1247 // Thread.stop support
1248 void send_thread_stop(oop throwable);
1249 AsyncRequests clear_special_runtime_exit_condition() {
1250 AsyncRequests x = _special_runtime_exit_condition;
1251 _special_runtime_exit_condition = _no_async_condition;
1252 return x;
1253 }
1254
1255 // Are any async conditions present?
1256 bool has_async_condition() { return (_special_runtime_exit_condition != _no_async_condition); }
1257
1258 void check_and_handle_async_exceptions(bool check_unsafe_error = true);
1259
1260 // these next two are also used for self-suspension and async exception support
1261 void handle_special_runtime_exit_condition(bool check_asyncs = true);
1262
1263 // Return true if JavaThread has an asynchronous condition or
1264 // if external suspension is requested.
1265 bool has_special_runtime_exit_condition() {
1266 // Because we don't use is_external_suspend_with_lock
1267 // it is possible that we won't see an asynchronous external suspend
1268 // request that has just gotten started, i.e., SR_lock grabbed but
1269 // _external_suspend field change either not made yet or not visible
1270 // yet. However, this is okay because the request is asynchronous and
1271 // we will see the new flag value the next time through. It's also
1272 // possible that the external suspend request is dropped after
1273 // we have checked is_external_suspend(), we will recheck its value
1274 // under SR_lock in java_suspend_self().
1275 return (_special_runtime_exit_condition != _no_async_condition) ||
1276 is_external_suspend() || is_deopt_suspend() || is_trace_suspend();
1277 }
1278
1279 void set_pending_unsafe_access_error() { _special_runtime_exit_condition = _async_unsafe_access_error; }
1280
1281 inline void set_pending_async_exception(oop e);
1282
1283 // Fast-locking support
1284 bool is_lock_owned(address adr) const;
1285
1286 // Accessors for vframe array top
1287 // The linked list of vframe arrays are sorted on sp. This means when we
1288 // unpack the head must contain the vframe array to unpack.
1289 void set_vframe_array_head(vframeArray* value) { _vframe_array_head = value; }
1290 vframeArray* vframe_array_head() const { return _vframe_array_head; }
1291
1292 // Side structure for deferring update of java frame locals until deopt occurs
1293 GrowableArray<jvmtiDeferredLocalVariableSet*>* deferred_locals() const { return _deferred_locals_updates; }
1294 void set_deferred_locals(GrowableArray<jvmtiDeferredLocalVariableSet *>* vf) { _deferred_locals_updates = vf; }
1295
1296 // These only really exist to make debugging deopt problems simpler
1297
1298 void set_vframe_array_last(vframeArray* value) { _vframe_array_last = value; }
1299 vframeArray* vframe_array_last() const { return _vframe_array_last; }
1300
1301 // The special resourceMark used during deoptimization
1302
1303 void set_deopt_mark(DeoptResourceMark* value) { _deopt_mark = value; }
1304 DeoptResourceMark* deopt_mark(void) { return _deopt_mark; }
1305
1306 intptr_t* must_deopt_id() { return _must_deopt_id; }
1307 void set_must_deopt_id(intptr_t* id) { _must_deopt_id = id; }
1308 void clear_must_deopt_id() { _must_deopt_id = NULL; }
1309
1310 void set_deopt_compiled_method(CompiledMethod* nm) { _deopt_nmethod = nm; }
1311 CompiledMethod* deopt_compiled_method() { return _deopt_nmethod; }
1312
1313 Method* callee_target() const { return _callee_target; }
1314 void set_callee_target (Method* x) { _callee_target = x; }
1315
1316 // Oop results of vm runtime calls
1317 oop vm_result() const { return _vm_result; }
1318 void set_vm_result (oop x) { _vm_result = x; }
1319
1320 Metadata* vm_result_2() const { return _vm_result_2; }
1321 void set_vm_result_2 (Metadata* x) { _vm_result_2 = x; }
1322
1323 MemRegion deferred_card_mark() const { return _deferred_card_mark; }
1324 void set_deferred_card_mark(MemRegion mr) { _deferred_card_mark = mr; }
1325
1326 #if INCLUDE_JVMCI
1327 int pending_deoptimization() const { return _pending_deoptimization; }
1328 oop pending_failed_speculation() const { return _pending_failed_speculation; }
1329 bool adjusting_comp_level() const { return _adjusting_comp_level; }
1330 void set_adjusting_comp_level(bool b) { _adjusting_comp_level = b; }
1331 bool has_pending_monitorenter() const { return _pending_monitorenter; }
1332 void set_pending_monitorenter(bool b) { _pending_monitorenter = b; }
1333 void set_pending_deoptimization(int reason) { _pending_deoptimization = reason; }
1334 void set_pending_failed_speculation(oop failed_speculation) { _pending_failed_speculation = failed_speculation; }
1335 void set_pending_transfer_to_interpreter(bool b) { _pending_transfer_to_interpreter = b; }
1336 void set_jvmci_alternate_call_target(address a) { assert(_jvmci._alternate_call_target == NULL, "must be"); _jvmci._alternate_call_target = a; }
1337 void set_jvmci_implicit_exception_pc(address a) { assert(_jvmci._implicit_exception_pc == NULL, "must be"); _jvmci._implicit_exception_pc = a; }
1338 #endif // INCLUDE_JVMCI
1339
1340 // Exception handling for compiled methods
1341 oop exception_oop() const { return _exception_oop; }
1342 address exception_pc() const { return _exception_pc; }
1343 address exception_handler_pc() const { return _exception_handler_pc; }
1344 bool is_method_handle_return() const { return _is_method_handle_return == 1; }
1345
1346 void set_exception_oop(oop o) { (void)const_cast<oop&>(_exception_oop = o); }
1347 void set_exception_pc(address a) { _exception_pc = a; }
1348 void set_exception_handler_pc(address a) { _exception_handler_pc = a; }
1349 void set_is_method_handle_return(bool value) { _is_method_handle_return = value ? 1 : 0; }
1350
1351 void clear_exception_oop_and_pc() {
1352 set_exception_oop(NULL);
1353 set_exception_pc(NULL);
1354 }
1355
1356 // Stack overflow support
1357 //
1358 // (small addresses)
1359 //
1360 // -- <-- stack_end() ---
1361 // | |
1362 // | red pages |
1363 // | |
1364 // -- <-- stack_red_zone_base() |
1365 // | |
1366 // | guard
1367 // | yellow pages zone
1368 // | |
1369 // | |
1370 // -- <-- stack_yellow_zone_base() |
1371 // | |
1372 // | |
1373 // | reserved pages |
1374 // | |
1375 // -- <-- stack_reserved_zone_base() --- ---
1376 // /|\ shadow <-- stack_overflow_limit() (somewhere in here)
1377 // | zone
1378 // \|/ size
1379 // some untouched memory ---
1380 //
1381 //
1382 // --
1383 // |
1384 // | shadow zone
1385 // |
1386 // --
1387 // x frame n
1388 // --
1389 // x frame n-1
1390 // x
1391 // --
1392 // ...
1393 //
1394 // --
1395 // x frame 0
1396 // -- <-- stack_base()
1397 //
1398 // (large addresses)
1399 //
1400
1401 private:
1402 // These values are derived from flags StackRedPages, StackYellowPages,
1403 // StackReservedPages and StackShadowPages. The zone size is determined
1404 // ergonomically if page_size > 4K.
1405 static size_t _stack_red_zone_size;
1406 static size_t _stack_yellow_zone_size;
1407 static size_t _stack_reserved_zone_size;
1408 static size_t _stack_shadow_zone_size;
1409 public:
1410 inline size_t stack_available(address cur_sp);
1411
1412 static size_t stack_red_zone_size() {
1413 assert(_stack_red_zone_size > 0, "Don't call this before the field is initialized.");
1414 return _stack_red_zone_size;
1415 }
1416 static void set_stack_red_zone_size(size_t s) {
1417 assert(is_aligned(s, os::vm_page_size()),
1418 "We can not protect if the red zone size is not page aligned.");
1419 assert(_stack_red_zone_size == 0, "This should be called only once.");
1420 _stack_red_zone_size = s;
1421 }
1422 address stack_red_zone_base() {
1423 return (address)(stack_end() + stack_red_zone_size());
1424 }
1425 bool in_stack_red_zone(address a) {
1426 return a <= stack_red_zone_base() && a >= stack_end();
1427 }
1428
1429 static size_t stack_yellow_zone_size() {
1430 assert(_stack_yellow_zone_size > 0, "Don't call this before the field is initialized.");
1431 return _stack_yellow_zone_size;
1432 }
1433 static void set_stack_yellow_zone_size(size_t s) {
1434 assert(is_aligned(s, os::vm_page_size()),
1435 "We can not protect if the yellow zone size is not page aligned.");
1436 assert(_stack_yellow_zone_size == 0, "This should be called only once.");
1437 _stack_yellow_zone_size = s;
1438 }
1439
1440 static size_t stack_reserved_zone_size() {
1441 // _stack_reserved_zone_size may be 0. This indicates the feature is off.
1442 return _stack_reserved_zone_size;
1443 }
1444 static void set_stack_reserved_zone_size(size_t s) {
1445 assert(is_aligned(s, os::vm_page_size()),
1446 "We can not protect if the reserved zone size is not page aligned.");
1447 assert(_stack_reserved_zone_size == 0, "This should be called only once.");
1448 _stack_reserved_zone_size = s;
1449 }
1450 address stack_reserved_zone_base() {
1451 return (address)(stack_end() +
1452 (stack_red_zone_size() + stack_yellow_zone_size() + stack_reserved_zone_size()));
1453 }
1454 bool in_stack_reserved_zone(address a) {
1455 return (a <= stack_reserved_zone_base()) &&
1456 (a >= (address)((intptr_t)stack_reserved_zone_base() - stack_reserved_zone_size()));
1457 }
1458
1459 static size_t stack_yellow_reserved_zone_size() {
1460 return _stack_yellow_zone_size + _stack_reserved_zone_size;
1461 }
1462 bool in_stack_yellow_reserved_zone(address a) {
1463 return (a <= stack_reserved_zone_base()) && (a >= stack_red_zone_base());
1464 }
1465
1466 // Size of red + yellow + reserved zones.
1467 static size_t stack_guard_zone_size() {
1468 return stack_red_zone_size() + stack_yellow_reserved_zone_size();
1469 }
1470
1471 static size_t stack_shadow_zone_size() {
1472 assert(_stack_shadow_zone_size > 0, "Don't call this before the field is initialized.");
1473 return _stack_shadow_zone_size;
1474 }
1475 static void set_stack_shadow_zone_size(size_t s) {
1476 // The shadow area is not allocated or protected, so
1477 // it needs not be page aligned.
1478 // But the stack bang currently assumes that it is a
1479 // multiple of page size. This guarantees that the bang
1480 // loop touches all pages in the shadow zone.
1481 // This can be guaranteed differently, as well. E.g., if
1482 // the page size is a multiple of 4K, banging in 4K steps
1483 // suffices to touch all pages. (Some pages are banged
1484 // several times, though.)
1485 assert(is_aligned(s, os::vm_page_size()),
1486 "Stack bang assumes multiple of page size.");
1487 assert(_stack_shadow_zone_size == 0, "This should be called only once.");
1488 _stack_shadow_zone_size = s;
1489 }
1490
1491 void create_stack_guard_pages();
1492 void remove_stack_guard_pages();
1493
1494 void enable_stack_reserved_zone();
1495 void disable_stack_reserved_zone();
1496 void enable_stack_yellow_reserved_zone();
1497 void disable_stack_yellow_reserved_zone();
1498 void enable_stack_red_zone();
1499 void disable_stack_red_zone();
1500
1501 inline bool stack_guard_zone_unused();
1502 inline bool stack_yellow_reserved_zone_disabled();
1503 inline bool stack_reserved_zone_disabled();
1504 inline bool stack_guards_enabled();
1505
1506 address reserved_stack_activation() const { return _reserved_stack_activation; }
1507 void set_reserved_stack_activation(address addr) {
1508 assert(_reserved_stack_activation == stack_base()
1509 || _reserved_stack_activation == NULL
1510 || addr == stack_base(), "Must not be set twice");
1511 _reserved_stack_activation = addr;
1512 }
1513
1514 // Attempt to reguard the stack after a stack overflow may have occurred.
1515 // Returns true if (a) guard pages are not needed on this thread, (b) the
1516 // pages are already guarded, or (c) the pages were successfully reguarded.
1517 // Returns false if there is not enough stack space to reguard the pages, in
1518 // which case the caller should unwind a frame and try again. The argument
1519 // should be the caller's (approximate) sp.
1520 bool reguard_stack(address cur_sp);
1521 // Similar to above but see if current stackpoint is out of the guard area
1522 // and reguard if possible.
1523 bool reguard_stack(void);
1524
1525 address stack_overflow_limit() { return _stack_overflow_limit; }
1526 void set_stack_overflow_limit() {
1527 _stack_overflow_limit =
1528 stack_end() + MAX2(JavaThread::stack_guard_zone_size(), JavaThread::stack_shadow_zone_size());
1529 }
1530
1531 // Misc. accessors/mutators
1532 void set_do_not_unlock(void) { _do_not_unlock_if_synchronized = true; }
1533 void clr_do_not_unlock(void) { _do_not_unlock_if_synchronized = false; }
1534 bool do_not_unlock(void) { return _do_not_unlock_if_synchronized; }
1535
1536 #ifndef PRODUCT
1537 void record_jump(address target, address instr, const char* file, int line);
1538 #endif // PRODUCT
1539
1540 // For assembly stub generation
1541 static ByteSize threadObj_offset() { return byte_offset_of(JavaThread, _threadObj); }
1542 #ifndef PRODUCT
1543 static ByteSize jmp_ring_index_offset() { return byte_offset_of(JavaThread, _jmp_ring_index); }
1544 static ByteSize jmp_ring_offset() { return byte_offset_of(JavaThread, _jmp_ring); }
1545 #endif // PRODUCT
1546 static ByteSize jni_environment_offset() { return byte_offset_of(JavaThread, _jni_environment); }
1547 static ByteSize pending_jni_exception_check_fn_offset() {
1548 return byte_offset_of(JavaThread, _pending_jni_exception_check_fn);
1549 }
1550 static ByteSize last_Java_sp_offset() {
1551 return byte_offset_of(JavaThread, _anchor) + JavaFrameAnchor::last_Java_sp_offset();
1552 }
1553 static ByteSize last_Java_pc_offset() {
1554 return byte_offset_of(JavaThread, _anchor) + JavaFrameAnchor::last_Java_pc_offset();
1555 }
1556 static ByteSize frame_anchor_offset() {
1557 return byte_offset_of(JavaThread, _anchor);
1558 }
1559 static ByteSize callee_target_offset() { return byte_offset_of(JavaThread, _callee_target); }
1560 static ByteSize vm_result_offset() { return byte_offset_of(JavaThread, _vm_result); }
1561 static ByteSize vm_result_2_offset() { return byte_offset_of(JavaThread, _vm_result_2); }
1562 static ByteSize thread_state_offset() { return byte_offset_of(JavaThread, _thread_state); }
1563 static ByteSize saved_exception_pc_offset() { return byte_offset_of(JavaThread, _saved_exception_pc); }
1564 static ByteSize osthread_offset() { return byte_offset_of(JavaThread, _osthread); }
1565 #if INCLUDE_JVMCI
1566 static ByteSize pending_deoptimization_offset() { return byte_offset_of(JavaThread, _pending_deoptimization); }
1567 static ByteSize pending_monitorenter_offset() { return byte_offset_of(JavaThread, _pending_monitorenter); }
1568 static ByteSize pending_failed_speculation_offset() { return byte_offset_of(JavaThread, _pending_failed_speculation); }
1569 static ByteSize jvmci_alternate_call_target_offset() { return byte_offset_of(JavaThread, _jvmci._alternate_call_target); }
1570 static ByteSize jvmci_implicit_exception_pc_offset() { return byte_offset_of(JavaThread, _jvmci._implicit_exception_pc); }
1571 static ByteSize jvmci_counters_offset() { return byte_offset_of(JavaThread, _jvmci_counters); }
1572 #endif // INCLUDE_JVMCI
1573 static ByteSize exception_oop_offset() { return byte_offset_of(JavaThread, _exception_oop); }
1574 static ByteSize exception_pc_offset() { return byte_offset_of(JavaThread, _exception_pc); }
1575 static ByteSize exception_handler_pc_offset() { return byte_offset_of(JavaThread, _exception_handler_pc); }
1576 static ByteSize stack_overflow_limit_offset() { return byte_offset_of(JavaThread, _stack_overflow_limit); }
1577 static ByteSize is_method_handle_return_offset() { return byte_offset_of(JavaThread, _is_method_handle_return); }
1578 static ByteSize stack_guard_state_offset() { return byte_offset_of(JavaThread, _stack_guard_state); }
1579 static ByteSize reserved_stack_activation_offset() { return byte_offset_of(JavaThread, _reserved_stack_activation); }
1580 static ByteSize suspend_flags_offset() { return byte_offset_of(JavaThread, _suspend_flags); }
1581
1582 static ByteSize do_not_unlock_if_synchronized_offset() { return byte_offset_of(JavaThread, _do_not_unlock_if_synchronized); }
1583 static ByteSize should_post_on_exceptions_flag_offset() {
1584 return byte_offset_of(JavaThread, _should_post_on_exceptions_flag);
1585 }
1586
1587 #if INCLUDE_ALL_GCS
1588 static ByteSize satb_mark_queue_offset() { return byte_offset_of(JavaThread, _satb_mark_queue); }
1589 static ByteSize dirty_card_queue_offset() { return byte_offset_of(JavaThread, _dirty_card_queue); }
1590 #endif // INCLUDE_ALL_GCS
1591
1592 // Returns the jni environment for this thread
1593 JNIEnv* jni_environment() { return &_jni_environment; }
1594
1595 static JavaThread* thread_from_jni_environment(JNIEnv* env) {
1596 JavaThread *thread_from_jni_env = (JavaThread*)((intptr_t)env - in_bytes(jni_environment_offset()));
1597 // Only return NULL if thread is off the thread list; starting to
1598 // exit should not return NULL.
1599 if (thread_from_jni_env->is_terminated()) {
1600 thread_from_jni_env->block_if_vm_exited();
1601 return NULL;
1602 } else {
1603 return thread_from_jni_env;
1604 }
1605 }
1606
1607 // JNI critical regions. These can nest.
1608 bool in_critical() { return _jni_active_critical > 0; }
1609 bool in_last_critical() { return _jni_active_critical == 1; }
1610 void enter_critical() {
1611 assert(Thread::current() == this ||
1612 (Thread::current()->is_VM_thread() &&
1613 SafepointSynchronize::is_synchronizing()),
1614 "this must be current thread or synchronizing");
1615 _jni_active_critical++;
1616 }
1617 void exit_critical() {
1618 assert(Thread::current() == this, "this must be current thread");
1619 _jni_active_critical--;
1620 assert(_jni_active_critical >= 0, "JNI critical nesting problem?");
1621 }
1622
1623 // Checked JNI: is the programmer required to check for exceptions, if so specify
1624 // which function name. Returning to a Java frame should implicitly clear the
1625 // pending check, this is done for Native->Java transitions (i.e. user JNI code).
1626 // VM->Java transistions are not cleared, it is expected that JNI code enclosed
1627 // within ThreadToNativeFromVM makes proper exception checks (i.e. VM internal).
1628 bool is_pending_jni_exception_check() const { return _pending_jni_exception_check_fn != NULL; }
1629 void clear_pending_jni_exception_check() { _pending_jni_exception_check_fn = NULL; }
1630 const char* get_pending_jni_exception_check() const { return _pending_jni_exception_check_fn; }
1631 void set_pending_jni_exception_check(const char* fn_name) { _pending_jni_exception_check_fn = (char*) fn_name; }
1632
1633 // For deadlock detection
1634 int depth_first_number() { return _depth_first_number; }
1635 void set_depth_first_number(int dfn) { _depth_first_number = dfn; }
1636
1637 private:
1638 void set_monitor_chunks(MonitorChunk* monitor_chunks) { _monitor_chunks = monitor_chunks; }
1639
1640 public:
1641 MonitorChunk* monitor_chunks() const { return _monitor_chunks; }
1642 void add_monitor_chunk(MonitorChunk* chunk);
1643 void remove_monitor_chunk(MonitorChunk* chunk);
1644 bool in_deopt_handler() const { return _in_deopt_handler > 0; }
1645 void inc_in_deopt_handler() { _in_deopt_handler++; }
1646 void dec_in_deopt_handler() {
1647 assert(_in_deopt_handler > 0, "mismatched deopt nesting");
1648 if (_in_deopt_handler > 0) { // robustness
1649 _in_deopt_handler--;
1650 }
1651 }
1652
1653 private:
1654 void set_entry_point(ThreadFunction entry_point) { _entry_point = entry_point; }
1655
1656 public:
1657
1658 // Frame iteration; calls the function f for all frames on the stack
1659 void frames_do(void f(frame*, const RegisterMap*));
1660
1661 // Memory operations
1662 void oops_do(OopClosure* f, CodeBlobClosure* cf);
1663
1664 // Sweeper operations
1665 virtual void nmethods_do(CodeBlobClosure* cf);
1666
1667 // RedefineClasses Support
1668 void metadata_do(void f(Metadata*));
1669
1670 // Misc. operations
1671 char* name() const { return (char*)get_thread_name(); }
1672 void print_on(outputStream* st) const;
1673 void print_value();
1674 void print_thread_state_on(outputStream*) const PRODUCT_RETURN;
1675 void print_thread_state() const PRODUCT_RETURN;
1676 void print_on_error(outputStream* st, char* buf, int buflen) const;
1677 void print_name_on_error(outputStream* st, char* buf, int buflen) const;
1678 void verify();
1679 const char* get_thread_name() const;
1680 private:
1681 // factor out low-level mechanics for use in both normal and error cases
1682 const char* get_thread_name_string(char* buf = NULL, int buflen = 0) const;
1683 public:
1684 const char* get_threadgroup_name() const;
1685 const char* get_parent_name() const;
1686
1687 // Accessing frames
1688 frame last_frame() {
1689 _anchor.make_walkable(this);
1690 return pd_last_frame();
1691 }
1692 javaVFrame* last_java_vframe(RegisterMap* reg_map);
1693
1694 // Returns method at 'depth' java or native frames down the stack
1695 // Used for security checks
1696 Klass* security_get_caller_class(int depth);
1697
1698 // Print stack trace in external format
1699 void print_stack_on(outputStream* st);
1700 void print_stack() { print_stack_on(tty); }
1701
1702 // Print stack traces in various internal formats
1703 void trace_stack() PRODUCT_RETURN;
1704 void trace_stack_from(vframe* start_vf) PRODUCT_RETURN;
1705 void trace_frames() PRODUCT_RETURN;
1706 void trace_oops() PRODUCT_RETURN;
1707
1708 // Print an annotated view of the stack frames
1709 void print_frame_layout(int depth = 0, bool validate_only = false) NOT_DEBUG_RETURN;
1710 void validate_frame_layout() {
1711 print_frame_layout(0, true);
1712 }
1713
1714 // Returns the number of stack frames on the stack
1715 int depth() const;
1716
1717 // Function for testing deoptimization
1718 void deoptimize();
1719 void make_zombies();
1720
1721 void deoptimized_wrt_marked_nmethods();
1722
1723 public:
1724 // Returns the running thread as a JavaThread
1725 static inline JavaThread* current();
1726
1727 // Returns the active Java thread. Do not use this if you know you are calling
1728 // from a JavaThread, as it's slower than JavaThread::current. If called from
1729 // the VMThread, it also returns the JavaThread that instigated the VMThread's
1730 // operation. You may not want that either.
1731 static JavaThread* active();
1732
1733 inline CompilerThread* as_CompilerThread();
1734
1735 public:
1736 virtual void run();
1737 void thread_main_inner();
1738
1739 private:
1740 // PRIVILEGED STACK
1741 PrivilegedElement* _privileged_stack_top;
1742 GrowableArray<oop>* _array_for_gc;
1743 public:
1744
1745 // Returns the privileged_stack information.
1746 PrivilegedElement* privileged_stack_top() const { return _privileged_stack_top; }
1747 void set_privileged_stack_top(PrivilegedElement *e) { _privileged_stack_top = e; }
1748 void register_array_for_gc(GrowableArray<oop>* array) { _array_for_gc = array; }
1749
1750 public:
1751 // Thread local information maintained by JVMTI.
1752 void set_jvmti_thread_state(JvmtiThreadState *value) { _jvmti_thread_state = value; }
1753 // A JvmtiThreadState is lazily allocated. This jvmti_thread_state()
1754 // getter is used to get this JavaThread's JvmtiThreadState if it has
1755 // one which means NULL can be returned. JvmtiThreadState::state_for()
1756 // is used to get the specified JavaThread's JvmtiThreadState if it has
1757 // one or it allocates a new JvmtiThreadState for the JavaThread and
1758 // returns it. JvmtiThreadState::state_for() will return NULL only if
1759 // the specified JavaThread is exiting.
1760 JvmtiThreadState *jvmti_thread_state() const { return _jvmti_thread_state; }
1761 static ByteSize jvmti_thread_state_offset() { return byte_offset_of(JavaThread, _jvmti_thread_state); }
1762 void set_jvmti_get_loaded_classes_closure(JvmtiGetLoadedClassesClosure* value) { _jvmti_get_loaded_classes_closure = value; }
1763 JvmtiGetLoadedClassesClosure* get_jvmti_get_loaded_classes_closure() const { return _jvmti_get_loaded_classes_closure; }
1764
1765 // JVMTI PopFrame support
1766 // Setting and clearing popframe_condition
1767 // All of these enumerated values are bits. popframe_pending
1768 // indicates that a PopFrame() has been requested and not yet been
1769 // completed. popframe_processing indicates that that PopFrame() is in
1770 // the process of being completed. popframe_force_deopt_reexecution_bit
1771 // indicates that special handling is required when returning to a
1772 // deoptimized caller.
1773 enum PopCondition {
1774 popframe_inactive = 0x00,
1775 popframe_pending_bit = 0x01,
1776 popframe_processing_bit = 0x02,
1777 popframe_force_deopt_reexecution_bit = 0x04
1778 };
1779 PopCondition popframe_condition() { return (PopCondition) _popframe_condition; }
1780 void set_popframe_condition(PopCondition c) { _popframe_condition = c; }
1781 void set_popframe_condition_bit(PopCondition c) { _popframe_condition |= c; }
1782 void clear_popframe_condition() { _popframe_condition = popframe_inactive; }
1783 static ByteSize popframe_condition_offset() { return byte_offset_of(JavaThread, _popframe_condition); }
1784 bool has_pending_popframe() { return (popframe_condition() & popframe_pending_bit) != 0; }
1785 bool popframe_forcing_deopt_reexecution() { return (popframe_condition() & popframe_force_deopt_reexecution_bit) != 0; }
1786 void clear_popframe_forcing_deopt_reexecution() { _popframe_condition &= ~popframe_force_deopt_reexecution_bit; }
1787 #ifdef CC_INTERP
1788 bool pop_frame_pending(void) { return ((_popframe_condition & popframe_pending_bit) != 0); }
1789 void clr_pop_frame_pending(void) { _popframe_condition = popframe_inactive; }
1790 bool pop_frame_in_process(void) { return ((_popframe_condition & popframe_processing_bit) != 0); }
1791 void set_pop_frame_in_process(void) { _popframe_condition |= popframe_processing_bit; }
1792 void clr_pop_frame_in_process(void) { _popframe_condition &= ~popframe_processing_bit; }
1793 #endif
1794
1795 int frames_to_pop_failed_realloc() const { return _frames_to_pop_failed_realloc; }
1796 void set_frames_to_pop_failed_realloc(int nb) { _frames_to_pop_failed_realloc = nb; }
1797 void dec_frames_to_pop_failed_realloc() { _frames_to_pop_failed_realloc--; }
1798
1799 private:
1800 // Saved incoming arguments to popped frame.
1801 // Used only when popped interpreted frame returns to deoptimized frame.
1802 void* _popframe_preserved_args;
1803 int _popframe_preserved_args_size;
1804
1805 public:
1806 void popframe_preserve_args(ByteSize size_in_bytes, void* start);
1807 void* popframe_preserved_args();
1808 ByteSize popframe_preserved_args_size();
1809 WordSize popframe_preserved_args_size_in_words();
1810 void popframe_free_preserved_args();
1811
1812
1813 private:
1814 JvmtiThreadState *_jvmti_thread_state;
1815 JvmtiGetLoadedClassesClosure* _jvmti_get_loaded_classes_closure;
1816
1817 // Used by the interpreter in fullspeed mode for frame pop, method
1818 // entry, method exit and single stepping support. This field is
1819 // only set to non-zero by the VM_EnterInterpOnlyMode VM operation.
1820 // It can be set to zero asynchronously (i.e., without a VM operation
1821 // or a lock) so we have to be very careful.
1822 int _interp_only_mode;
1823
1824 public:
1825 // used by the interpreter for fullspeed debugging support (see above)
1826 static ByteSize interp_only_mode_offset() { return byte_offset_of(JavaThread, _interp_only_mode); }
1827 bool is_interp_only_mode() { return (_interp_only_mode != 0); }
1828 int get_interp_only_mode() { return _interp_only_mode; }
1829 void increment_interp_only_mode() { ++_interp_only_mode; }
1830 void decrement_interp_only_mode() { --_interp_only_mode; }
1831
1832 // support for cached flag that indicates whether exceptions need to be posted for this thread
1833 // if this is false, we can avoid deoptimizing when events are thrown
1834 // this gets set to reflect whether jvmtiExport::post_exception_throw would actually do anything
1835 private:
1836 int _should_post_on_exceptions_flag;
1837
1838 public:
1839 int should_post_on_exceptions_flag() { return _should_post_on_exceptions_flag; }
1840 void set_should_post_on_exceptions_flag(int val) { _should_post_on_exceptions_flag = val; }
1841
1842 private:
1843 ThreadStatistics *_thread_stat;
1844
1845 public:
1846 ThreadStatistics* get_thread_stat() const { return _thread_stat; }
1847
1848 // Return a blocker object for which this thread is blocked parking.
1849 oop current_park_blocker();
1850
1851 private:
1852 static size_t _stack_size_at_create;
1853
1854 public:
1855 static inline size_t stack_size_at_create(void) {
1856 return _stack_size_at_create;
1857 }
1858 static inline void set_stack_size_at_create(size_t value) {
1859 _stack_size_at_create = value;
1860 }
1861
1862 #if INCLUDE_ALL_GCS
1863 // SATB marking queue support
1864 SATBMarkQueue& satb_mark_queue() { return _satb_mark_queue; }
1865 static SATBMarkQueueSet& satb_mark_queue_set() {
1866 return _satb_mark_queue_set;
1867 }
1868
1869 // Dirty card queue support
1870 DirtyCardQueue& dirty_card_queue() { return _dirty_card_queue; }
1871 static DirtyCardQueueSet& dirty_card_queue_set() {
1872 return _dirty_card_queue_set;
1873 }
1874 #endif // INCLUDE_ALL_GCS
1875
1876 // This method initializes the SATB and dirty card queues before a
1877 // JavaThread is added to the Java thread list. Right now, we don't
1878 // have to do anything to the dirty card queue (it should have been
1879 // activated when the thread was created), but we have to activate
1880 // the SATB queue if the thread is created while a marking cycle is
1881 // in progress. The activation / de-activation of the SATB queues at
1882 // the beginning / end of a marking cycle is done during safepoints
1883 // so we have to make sure this method is called outside one to be
1884 // able to safely read the active field of the SATB queue set. Right
1885 // now, it is called just before the thread is added to the Java
1886 // thread list in the Threads::add() method. That method is holding
1887 // the Threads_lock which ensures we are outside a safepoint. We
1888 // cannot do the obvious and set the active field of the SATB queue
1889 // when the thread is created given that, in some cases, safepoints
1890 // might happen between the JavaThread constructor being called and the
1891 // thread being added to the Java thread list (an example of this is
1892 // when the structure for the DestroyJavaVM thread is created).
1893 #if INCLUDE_ALL_GCS
1894 void initialize_queues();
1895 #else // INCLUDE_ALL_GCS
1896 void initialize_queues() { }
1897 #endif // INCLUDE_ALL_GCS
1898
1899 // Machine dependent stuff
1900 #include OS_CPU_HEADER(thread)
1901
1902 public:
1903 void set_blocked_on_compilation(bool value) {
1904 _blocked_on_compilation = value;
1905 }
1906
1907 bool blocked_on_compilation() {
1908 return _blocked_on_compilation;
1909 }
1910 protected:
1911 bool _blocked_on_compilation;
1912
1913
1914 // JSR166 per-thread parker
1915 private:
1916 Parker* _parker;
1917 public:
1918 Parker* parker() { return _parker; }
1919
1920 // Biased locking support
1921 private:
1922 GrowableArray<MonitorInfo*>* _cached_monitor_info;
1923 public:
1924 GrowableArray<MonitorInfo*>* cached_monitor_info() { return _cached_monitor_info; }
1925 void set_cached_monitor_info(GrowableArray<MonitorInfo*>* info) { _cached_monitor_info = info; }
1926
1927 // clearing/querying jni attach status
1928 bool is_attaching_via_jni() const { return _jni_attach_state == _attaching_via_jni; }
1929 bool has_attached_via_jni() const { return is_attaching_via_jni() || _jni_attach_state == _attached_via_jni; }
1930 inline void set_done_attaching_via_jni();
1931 };
1932
1933 // Inline implementation of JavaThread::current
1934 inline JavaThread* JavaThread::current() {
1935 Thread* thread = Thread::current();
1936 assert(thread->is_Java_thread(), "just checking");
1937 return (JavaThread*)thread;
1938 }
1939
1940 inline CompilerThread* JavaThread::as_CompilerThread() {
1941 assert(is_Compiler_thread(), "just checking");
1942 return (CompilerThread*)this;
1943 }
1944
1945 // Dedicated thread to sweep the code cache
1946 class CodeCacheSweeperThread : public JavaThread {
1947 CompiledMethod* _scanned_compiled_method; // nmethod being scanned by the sweeper
1948 public:
1949 CodeCacheSweeperThread();
1950 // Track the nmethod currently being scanned by the sweeper
1951 void set_scanned_compiled_method(CompiledMethod* cm) {
1952 assert(_scanned_compiled_method == NULL || cm == NULL, "should reset to NULL before writing a new value");
1953 _scanned_compiled_method = cm;
1954 }
1955
1956 // Hide sweeper thread from external view.
1957 bool is_hidden_from_external_view() const { return true; }
1958
1959 bool is_Code_cache_sweeper_thread() const { return true; }
1960
1961 // Prevent GC from unloading _scanned_compiled_method
1962 void oops_do(OopClosure* f, CodeBlobClosure* cf);
1963 void nmethods_do(CodeBlobClosure* cf);
1964 };
1965
1966 // A thread used for Compilation.
1967 class CompilerThread : public JavaThread {
1968 friend class VMStructs;
1969 private:
1970 CompilerCounters* _counters;
1971
1972 ciEnv* _env;
1973 CompileLog* _log;
1974 CompileTask* _task;
1975 CompileQueue* _queue;
1976 BufferBlob* _buffer_blob;
1977
1978 AbstractCompiler* _compiler;
1979
1980 public:
1981
1982 static CompilerThread* current();
1983
1984 CompilerThread(CompileQueue* queue, CompilerCounters* counters);
1985
1986 bool is_Compiler_thread() const { return true; }
1987
1988 virtual bool can_call_java() const;
1989
1990 // Hide native compiler threads from external view.
1991 bool is_hidden_from_external_view() const { return !can_call_java(); }
1992
1993 void set_compiler(AbstractCompiler* c) { _compiler = c; }
1994 AbstractCompiler* compiler() const { return _compiler; }
1995
1996 CompileQueue* queue() const { return _queue; }
1997 CompilerCounters* counters() const { return _counters; }
1998
1999 // Get/set the thread's compilation environment.
2000 ciEnv* env() { return _env; }
2001 void set_env(ciEnv* env) { _env = env; }
2002
2003 BufferBlob* get_buffer_blob() const { return _buffer_blob; }
2004 void set_buffer_blob(BufferBlob* b) { _buffer_blob = b; }
2005
2006 // Get/set the thread's logging information
2007 CompileLog* log() { return _log; }
2008 void init_log(CompileLog* log) {
2009 // Set once, for good.
2010 assert(_log == NULL, "set only once");
2011 _log = log;
2012 }
2013
2014 #ifndef PRODUCT
2015 private:
2016 IdealGraphPrinter *_ideal_graph_printer;
2017 public:
2018 IdealGraphPrinter *ideal_graph_printer() { return _ideal_graph_printer; }
2019 void set_ideal_graph_printer(IdealGraphPrinter *n) { _ideal_graph_printer = n; }
2020 #endif
2021
2022 // Get/set the thread's current task
2023 CompileTask* task() { return _task; }
2024 void set_task(CompileTask* task) { _task = task; }
2025 };
2026
2027 inline CompilerThread* CompilerThread::current() {
2028 return JavaThread::current()->as_CompilerThread();
2029 }
2030
2031 // The active thread queue. It also keeps track of the current used
2032 // thread priorities.
2033 class Threads: AllStatic {
2034 friend class VMStructs;
2035 private:
2036 static JavaThread* _thread_list;
2037 static int _number_of_threads;
2038 static int _number_of_non_daemon_threads;
2039 static int _return_code;
2040 static int _thread_claim_parity;
2041 #ifdef ASSERT
2042 static bool _vm_complete;
2043 #endif
2044
2045 static void initialize_java_lang_classes(JavaThread* main_thread, TRAPS);
2046 static void initialize_jsr292_core_classes(TRAPS);
2047 public:
2048 // Thread management
2049 // force_daemon is a concession to JNI, where we may need to add a
2050 // thread to the thread list before allocating its thread object
2051 static void add(JavaThread* p, bool force_daemon = false);
2052 static void remove(JavaThread* p);
2053 static bool includes(JavaThread* p);
2054 static JavaThread* first() { return _thread_list; }
2055 static void threads_do(ThreadClosure* tc);
2056 static void parallel_java_threads_do(ThreadClosure* tc);
2057
2058 // Initializes the vm and creates the vm thread
2059 static jint create_vm(JavaVMInitArgs* args, bool* canTryAgain);
2060 static void convert_vm_init_libraries_to_agents();
2061 static void create_vm_init_libraries();
2062 static void create_vm_init_agents();
2063 static void shutdown_vm_agents();
2064 static bool destroy_vm();
2065 // Supported VM versions via JNI
2066 // Includes JNI_VERSION_1_1
2067 static jboolean is_supported_jni_version_including_1_1(jint version);
2068 // Does not include JNI_VERSION_1_1
2069 static jboolean is_supported_jni_version(jint version);
2070
2071 // The "thread claim parity" provides a way for threads to be claimed
2072 // by parallel worker tasks.
2073 //
2074 // Each thread contains a a "parity" field. A task will claim the
2075 // thread only if its parity field is the same as the global parity,
2076 // which is updated by calling change_thread_claim_parity().
2077 //
2078 // For this to work change_thread_claim_parity() needs to be called
2079 // exactly once in sequential code before starting parallel tasks
2080 // that should claim threads.
2081 //
2082 // New threads get their parity set to 0 and change_thread_claim_parity()
2083 // never set the global parity to 0.
2084 static int thread_claim_parity() { return _thread_claim_parity; }
2085 static void change_thread_claim_parity();
2086 static void assert_all_threads_claimed() NOT_DEBUG_RETURN;
2087
2088 // Apply "f->do_oop" to all root oops in all threads.
2089 // This version may only be called by sequential code.
2090 static void oops_do(OopClosure* f, CodeBlobClosure* cf);
2091 // This version may be called by sequential or parallel code.
2092 static void possibly_parallel_oops_do(bool is_par, OopClosure* f, CodeBlobClosure* cf);
2093 // This creates a list of GCTasks, one per thread.
2094 static void create_thread_roots_tasks(GCTaskQueue* q);
2095 // This creates a list of GCTasks, one per thread, for marking objects.
2096 static void create_thread_roots_marking_tasks(GCTaskQueue* q);
2097
2098 // Apply "f->do_oop" to roots in all threads that
2099 // are part of compiled frames
2100 static void compiled_frame_oops_do(OopClosure* f, CodeBlobClosure* cf);
2101
2102 static void convert_hcode_pointers();
2103 static void restore_hcode_pointers();
2104
2105 // Sweeper
2106 static void nmethods_do(CodeBlobClosure* cf);
2107
2108 // RedefineClasses support
2109 static void metadata_do(void f(Metadata*));
2110 static void metadata_handles_do(void f(Metadata*));
2111
2112 #ifdef ASSERT
2113 static bool is_vm_complete() { return _vm_complete; }
2114 #endif
2115
2116 // Verification
2117 static void verify();
2118 static void print_on(outputStream* st, bool print_stacks, bool internal_format, bool print_concurrent_locks);
2119 static void print(bool print_stacks, bool internal_format) {
2120 // this function is only used by debug.cpp
2121 print_on(tty, print_stacks, internal_format, false /* no concurrent lock printed */);
2122 }
2123 static void print_on_error(outputStream* st, Thread* current, char* buf, int buflen);
2124 static void print_on_error(Thread* this_thread, outputStream* st, Thread* current, char* buf,
2125 int buflen, bool* found_current);
2126 static void print_threads_compiling(outputStream* st, char* buf, int buflen);
2127
2128 // Get Java threads that are waiting to enter a monitor. If doLock
2129 // is true, then Threads_lock is grabbed as needed. Otherwise, the
2130 // VM needs to be at a safepoint.
2131 static GrowableArray<JavaThread*>* get_pending_threads(int count,
2132 address monitor, bool doLock);
2133
2134 // Get owning Java thread from the monitor's owner field. If doLock
2135 // is true, then Threads_lock is grabbed as needed. Otherwise, the
2136 // VM needs to be at a safepoint.
2137 static JavaThread *owning_thread_from_monitor_owner(address owner,
2138 bool doLock);
2139
2140 // Number of threads on the active threads list
2141 static int number_of_threads() { return _number_of_threads; }
2142 // Number of non-daemon threads on the active threads list
2143 static int number_of_non_daemon_threads() { return _number_of_non_daemon_threads; }
2144
2145 // Deoptimizes all frames tied to marked nmethods
2146 static void deoptimized_wrt_marked_nmethods();
2147
2148 static JavaThread* find_java_thread_from_java_tid(jlong java_tid);
2149
2150 };
2151
2152
2153 // Thread iterator
2154 class ThreadClosure: public StackObj {
2155 public:
2156 virtual void do_thread(Thread* thread) = 0;
2157 };
2158
2159 class SignalHandlerMark: public StackObj {
2160 private:
2161 Thread* _thread;
2162 public:
2163 SignalHandlerMark(Thread* t) {
2164 _thread = t;
2165 if (_thread) _thread->enter_signal_handler();
2166 }
2167 ~SignalHandlerMark() {
2168 if (_thread) _thread->leave_signal_handler();
2169 _thread = NULL;
2170 }
2171 };
2172
2173
2174 #endif // SHARE_VM_RUNTIME_THREAD_HPP