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/threadHeapSampler.hpp"
44 #include "runtime/threadLocalStorage.hpp"
45 #include "runtime/unhandledOops.hpp"
46 #include "trace/traceBackend.hpp"
47 #include "trace/traceMacros.hpp"
48 #include "utilities/align.hpp"
49 #include "utilities/exceptions.hpp"
50 #include "utilities/macros.hpp"
51 #if INCLUDE_ALL_GCS
52 #include "gc/g1/dirtyCardQueue.hpp"
53 #include "gc/g1/satbMarkQueue.hpp"
54 #endif // INCLUDE_ALL_GCS
55 #ifdef ZERO
56 # include "stack_zero.hpp"
57 #endif
58
59 class ThreadSafepointState;
60 class ThreadsList;
61 class ThreadsSMRSupport;
62 class NestedThreadsList;
63
64 class JvmtiThreadState;
65 class JvmtiGetLoadedClassesClosure;
66 class ThreadStatistics;
67 class ConcurrentLocksDump;
68 class ParkEvent;
69 class Parker;
70
71 class ciEnv;
72 class CompileThread;
73 class CompileLog;
74 class CompileTask;
75 class CompileQueue;
76 class CompilerCounters;
77 class vframeArray;
78
79 class DeoptResourceMark;
80 class jvmtiDeferredLocalVariableSet;
81
82 class GCTaskQueue;
83 class ThreadClosure;
84 class IdealGraphPrinter;
85
86 class Metadata;
87 template <class T, MEMFLAGS F> class ChunkedList;
88 typedef ChunkedList<Metadata*, mtInternal> MetadataOnStackBuffer;
89
90 DEBUG_ONLY(class ResourceMark;)
91
92 class WorkerThread;
93
94 // Class hierarchy
95 // - Thread
96 // - NamedThread
97 // - VMThread
98 // - ConcurrentGCThread
99 // - WorkerThread
100 // - GangWorker
101 // - GCTaskThread
102 // - JavaThread
103 // - various subclasses eg CompilerThread, ServiceThread
104 // - WatcherThread
105
106 class Thread: public ThreadShadow {
107 friend class VMStructs;
108 friend class JVMCIVMStructs;
109 private:
110
111 #ifndef USE_LIBRARY_BASED_TLS_ONLY
112 // Current thread is maintained as a thread-local variable
113 static THREAD_LOCAL_DECL Thread* _thr_current;
114 #endif
115
116 // Exception handling
117 // (Note: _pending_exception and friends are in ThreadShadow)
118 //oop _pending_exception; // pending exception for current thread
119 // const char* _exception_file; // file information for exception (debugging only)
120 // int _exception_line; // line information for exception (debugging only)
121 protected:
122 // Support for forcing alignment of thread objects for biased locking
123 void* _real_malloc_address;
124
125 // JavaThread lifecycle support:
126 friend class ScanHazardPtrGatherProtectedThreadsClosure; // for cmpxchg_threads_hazard_ptr(), get_threads_hazard_ptr(), is_hazard_ptr_tagged() access
127 friend class ScanHazardPtrGatherThreadsListClosure; // for get_nested_threads_hazard_ptr(), get_threads_hazard_ptr(), untag_hazard_ptr() access
128 friend class ScanHazardPtrPrintMatchingThreadsClosure; // for get_threads_hazard_ptr(), is_hazard_ptr_tagged() access
129 friend class ThreadsListSetter; // for get_threads_hazard_ptr() access
130 friend class ThreadsSMRSupport; // for get_threads_hazard_ptr() access
131
132 ThreadsList* volatile _threads_hazard_ptr;
133 ThreadsList* cmpxchg_threads_hazard_ptr(ThreadsList* exchange_value, ThreadsList* compare_value);
134 ThreadsList* get_threads_hazard_ptr();
135 void set_threads_hazard_ptr(ThreadsList* new_list);
136 static bool is_hazard_ptr_tagged(ThreadsList* list) {
137 return (intptr_t(list) & intptr_t(1)) == intptr_t(1);
138 }
139 static ThreadsList* tag_hazard_ptr(ThreadsList* list) {
140 return (ThreadsList*)(intptr_t(list) | intptr_t(1));
141 }
142 static ThreadsList* untag_hazard_ptr(ThreadsList* list) {
143 return (ThreadsList*)(intptr_t(list) & ~intptr_t(1));
144 }
145 NestedThreadsList* _nested_threads_hazard_ptr;
146 NestedThreadsList* get_nested_threads_hazard_ptr() {
147 return _nested_threads_hazard_ptr;
148 }
149 void set_nested_threads_hazard_ptr(NestedThreadsList* value) {
150 assert(Threads_lock->owned_by_self(),
151 "must own Threads_lock for _nested_threads_hazard_ptr to be valid.");
152 _nested_threads_hazard_ptr = value;
153 }
154 // This field is enabled via -XX:+EnableThreadSMRStatistics:
155 uint _nested_threads_hazard_ptr_cnt;
156 void dec_nested_threads_hazard_ptr_cnt() {
157 assert(_nested_threads_hazard_ptr_cnt != 0, "mismatched {dec,inc}_nested_threads_hazard_ptr_cnt()");
158 _nested_threads_hazard_ptr_cnt--;
159 }
160 void inc_nested_threads_hazard_ptr_cnt() {
161 _nested_threads_hazard_ptr_cnt++;
162 }
163 uint nested_threads_hazard_ptr_cnt() {
164 return _nested_threads_hazard_ptr_cnt;
165 }
166
167 public:
168 void* operator new(size_t size) throw() { return allocate(size, true); }
169 void* operator new(size_t size, const std::nothrow_t& nothrow_constant) throw() {
170 return allocate(size, false); }
171 void operator delete(void* p);
172
173 protected:
174 static void* allocate(size_t size, bool throw_excpt, MEMFLAGS flags = mtThread);
175 private:
176
177 // ***************************************************************
178 // Suspend and resume support
179 // ***************************************************************
180 //
181 // VM suspend/resume no longer exists - it was once used for various
182 // things including safepoints but was deprecated and finally removed
183 // in Java 7. Because VM suspension was considered "internal" Java-level
184 // suspension was considered "external", and this legacy naming scheme
185 // remains.
186 //
187 // External suspend/resume requests come from JVM_SuspendThread,
188 // JVM_ResumeThread, JVMTI SuspendThread, and finally JVMTI
189 // ResumeThread. External
190 // suspend requests cause _external_suspend to be set and external
191 // resume requests cause _external_suspend to be cleared.
192 // External suspend requests do not nest on top of other external
193 // suspend requests. The higher level APIs reject suspend requests
194 // for already suspended threads.
195 //
196 // The external_suspend
197 // flag is checked by has_special_runtime_exit_condition() and java thread
198 // will self-suspend when handle_special_runtime_exit_condition() is
199 // called. Most uses of the _thread_blocked state in JavaThreads are
200 // considered the same as being externally suspended; if the blocking
201 // condition lifts, the JavaThread will self-suspend. Other places
202 // where VM checks for external_suspend include:
203 // + mutex granting (do not enter monitors when thread is suspended)
204 // + state transitions from _thread_in_native
205 //
206 // In general, java_suspend() does not wait for an external suspend
207 // request to complete. When it returns, the only guarantee is that
208 // the _external_suspend field is true.
209 //
210 // wait_for_ext_suspend_completion() is used to wait for an external
211 // suspend request to complete. External suspend requests are usually
212 // followed by some other interface call that requires the thread to
213 // be quiescent, e.g., GetCallTrace(). By moving the "wait time" into
214 // the interface that requires quiescence, we give the JavaThread a
215 // chance to self-suspend before we need it to be quiescent. This
216 // improves overall suspend/query performance.
217 //
218 // _suspend_flags controls the behavior of java_ suspend/resume.
219 // It must be set under the protection of SR_lock. Read from the flag is
220 // OK without SR_lock as long as the value is only used as a hint.
221 // (e.g., check _external_suspend first without lock and then recheck
222 // inside SR_lock and finish the suspension)
223 //
224 // _suspend_flags is also overloaded for other "special conditions" so
225 // that a single check indicates whether any special action is needed
226 // eg. for async exceptions.
227 // -------------------------------------------------------------------
228 // Notes:
229 // 1. The suspend/resume logic no longer uses ThreadState in OSThread
230 // but we still update its value to keep other part of the system (mainly
231 // JVMTI) happy. ThreadState is legacy code (see notes in
232 // osThread.hpp).
233 //
234 // 2. It would be more natural if set_external_suspend() is private and
235 // part of java_suspend(), but that probably would affect the suspend/query
236 // performance. Need more investigation on this.
237
238 // suspend/resume lock: used for self-suspend
239 Monitor* _SR_lock;
240
241 protected:
242 enum SuspendFlags {
243 // NOTE: avoid using the sign-bit as cc generates different test code
244 // when the sign-bit is used, and sometimes incorrectly - see CR 6398077
245
246 _external_suspend = 0x20000000U, // thread is asked to self suspend
247 _ext_suspended = 0x40000000U, // thread has self-suspended
248 _deopt_suspend = 0x10000000U, // thread needs to self suspend for deopt
249
250 _has_async_exception = 0x00000001U, // there is a pending async exception
251 _critical_native_unlock = 0x00000002U, // Must call back to unlock JNI critical lock
252
253 _trace_flag = 0x00000004U // call tracing backend
254 };
255
256 // various suspension related flags - atomically updated
257 // overloaded for async exception checking in check_special_condition_for_native_trans.
258 volatile uint32_t _suspend_flags;
259
260 private:
261 int _num_nested_signal;
262
263 DEBUG_ONLY(bool _suspendible_thread;)
264
265 public:
266 void enter_signal_handler() { _num_nested_signal++; }
267 void leave_signal_handler() { _num_nested_signal--; }
268 bool is_inside_signal_handler() const { return _num_nested_signal > 0; }
269
270 #ifdef ASSERT
271 void set_suspendible_thread() {
272 _suspendible_thread = true;
273 }
274
275 void clear_suspendible_thread() {
276 _suspendible_thread = false;
277 }
278
279 bool is_suspendible_thread() { return _suspendible_thread; }
280 #endif
281
282 private:
283 // Active_handles points to a block of handles
284 JNIHandleBlock* _active_handles;
285
286 // One-element thread local free list
287 JNIHandleBlock* _free_handle_block;
288
289 // Point to the last handle mark
290 HandleMark* _last_handle_mark;
291
292 // The parity of the last strong_roots iteration in which this thread was
293 // claimed as a task.
294 int _oops_do_parity;
295
296 public:
297 void set_last_handle_mark(HandleMark* mark) { _last_handle_mark = mark; }
298 HandleMark* last_handle_mark() const { return _last_handle_mark; }
299 private:
300
301 // debug support for checking if code does allow safepoints or not
302 // GC points in the VM can happen because of allocation, invoking a VM operation, or blocking on
303 // mutex, or blocking on an object synchronizer (Java locking).
304 // If !allow_safepoint(), then an assertion failure will happen in any of the above cases
305 // If !allow_allocation(), then an assertion failure will happen during allocation
306 // (Hence, !allow_safepoint() => !allow_allocation()).
307 //
308 // The two classes NoSafepointVerifier and No_Allocation_Verifier are used to set these counters.
309 //
310 NOT_PRODUCT(int _allow_safepoint_count;) // If 0, thread allow a safepoint to happen
311 debug_only(int _allow_allocation_count;) // If 0, the thread is allowed to allocate oops.
312
313 // Used by SkipGCALot class.
314 NOT_PRODUCT(bool _skip_gcalot;) // Should we elide gc-a-lot?
315
316 friend class NoAllocVerifier;
317 friend class NoSafepointVerifier;
318 friend class PauseNoSafepointVerifier;
319 friend class GCLocker;
320
321 volatile void* _polling_page; // Thread local polling page
322
323 ThreadLocalAllocBuffer _tlab; // Thread-local eden
324 jlong _allocated_bytes; // Cumulative number of bytes allocated on
325 // the Java heap
326 ThreadHeapSampler _heap_sampler; // For use when sampling the memory.
327
328 mutable TRACE_DATA _trace_data; // Thread-local data for tracing
329
330 int _vm_operation_started_count; // VM_Operation support
331 int _vm_operation_completed_count; // VM_Operation support
332
333 ObjectMonitor* _current_pending_monitor; // ObjectMonitor this thread
334 // is waiting to lock
335 bool _current_pending_monitor_is_from_java; // locking is from Java code
336
337 // ObjectMonitor on which this thread called Object.wait()
338 ObjectMonitor* _current_waiting_monitor;
339
340 // Private thread-local objectmonitor list - a simple cache organized as a SLL.
341 public:
342 ObjectMonitor* omFreeList;
343 int omFreeCount; // length of omFreeList
344 int omFreeProvision; // reload chunk size
345 ObjectMonitor* omInUseList; // SLL to track monitors in circulation
346 int omInUseCount; // length of omInUseList
347
348 #ifdef ASSERT
349 private:
350 bool _visited_for_critical_count;
351
352 public:
353 void set_visited_for_critical_count(bool z) { _visited_for_critical_count = z; }
354 bool was_visited_for_critical_count() const { return _visited_for_critical_count; }
355 #endif
356
357 public:
358 enum {
359 is_definitely_current_thread = true
360 };
361
362 // Constructor
363 Thread();
364 virtual ~Thread();
365
366 // Manage Thread::current()
367 void initialize_thread_current();
368 void clear_thread_current(); // TLS cleanup needed before threads terminate
369
370 public:
371 // thread entry point
372 virtual void run();
373
374 // Testers
375 virtual bool is_VM_thread() const { return false; }
376 virtual bool is_Java_thread() const { return false; }
377 virtual bool is_Compiler_thread() const { return false; }
378 virtual bool is_Code_cache_sweeper_thread() const { return false; }
379 virtual bool is_hidden_from_external_view() const { return false; }
380 virtual bool is_jvmti_agent_thread() const { return false; }
381 // True iff the thread can perform GC operations at a safepoint.
382 // Generally will be true only of VM thread and parallel GC WorkGang
383 // threads.
384 virtual bool is_GC_task_thread() const { return false; }
385 virtual bool is_Watcher_thread() const { return false; }
386 virtual bool is_ConcurrentGC_thread() const { return false; }
387 virtual bool is_Named_thread() const { return false; }
388 virtual bool is_Worker_thread() const { return false; }
389
390 // Can this thread make Java upcalls
391 virtual bool can_call_java() const { return false; }
392
393 // Casts
394 virtual WorkerThread* as_Worker_thread() const { return NULL; }
395
396 virtual char* name() const { return (char*)"Unknown thread"; }
397
398 // Returns the current thread (ASSERTS if NULL)
399 static inline Thread* current();
400 // Returns the current thread, or NULL if not attached
401 static inline Thread* current_or_null();
402 // Returns the current thread, or NULL if not attached, and is
403 // safe for use from signal-handlers
404 static inline Thread* current_or_null_safe();
405
406 // Common thread operations
407 #ifdef ASSERT
408 static void check_for_dangling_thread_pointer(Thread *thread);
409 #endif
410 static void set_priority(Thread* thread, ThreadPriority priority);
411 static ThreadPriority get_priority(const Thread* const thread);
412 static void start(Thread* thread);
413 static void interrupt(Thread* thr);
414 static bool is_interrupted(Thread* thr, bool clear_interrupted);
415
416 void set_native_thread_name(const char *name) {
417 assert(Thread::current() == this, "set_native_thread_name can only be called on the current thread");
418 os::set_native_thread_name(name);
419 }
420
421 ObjectMonitor** omInUseList_addr() { return (ObjectMonitor **)&omInUseList; }
422 Monitor* SR_lock() const { return _SR_lock; }
423
424 bool has_async_exception() const { return (_suspend_flags & _has_async_exception) != 0; }
425
426 inline void set_suspend_flag(SuspendFlags f);
427 inline void clear_suspend_flag(SuspendFlags f);
428
429 inline void set_has_async_exception();
430 inline void clear_has_async_exception();
431
432 bool do_critical_native_unlock() const { return (_suspend_flags & _critical_native_unlock) != 0; }
433
434 inline void set_critical_native_unlock();
435 inline void clear_critical_native_unlock();
436
437 inline void set_trace_flag();
438 inline void clear_trace_flag();
439
440 // Support for Unhandled Oop detection
441 // Add the field for both, fastdebug and debug, builds to keep
442 // Thread's fields layout the same.
443 // Note: CHECK_UNHANDLED_OOPS is defined only for fastdebug build.
444 #ifdef CHECK_UNHANDLED_OOPS
445 private:
446 UnhandledOops* _unhandled_oops;
447 #elif defined(ASSERT)
448 private:
449 void* _unhandled_oops;
450 #endif
451 #ifdef CHECK_UNHANDLED_OOPS
452 public:
453 UnhandledOops* unhandled_oops() { return _unhandled_oops; }
454 // Mark oop safe for gc. It may be stack allocated but won't move.
455 void allow_unhandled_oop(oop *op) {
456 if (CheckUnhandledOops) unhandled_oops()->allow_unhandled_oop(op);
457 }
458 // Clear oops at safepoint so crashes point to unhandled oop violator
459 void clear_unhandled_oops() {
460 if (CheckUnhandledOops) unhandled_oops()->clear_unhandled_oops();
461 }
462 #endif // CHECK_UNHANDLED_OOPS
463
464 public:
465 #ifndef PRODUCT
466 bool skip_gcalot() { return _skip_gcalot; }
467 void set_skip_gcalot(bool v) { _skip_gcalot = v; }
468 #endif
469
470 // Installs a pending exception to be inserted later
471 static void send_async_exception(oop thread_oop, oop java_throwable);
472
473 // Resource area
474 ResourceArea* resource_area() const { return _resource_area; }
475 void set_resource_area(ResourceArea* area) { _resource_area = area; }
476
477 OSThread* osthread() const { return _osthread; }
478 void set_osthread(OSThread* thread) { _osthread = thread; }
479
480 // JNI handle support
481 JNIHandleBlock* active_handles() const { return _active_handles; }
482 void set_active_handles(JNIHandleBlock* block) { _active_handles = block; }
483 JNIHandleBlock* free_handle_block() const { return _free_handle_block; }
484 void set_free_handle_block(JNIHandleBlock* block) { _free_handle_block = block; }
485
486 // Internal handle support
487 HandleArea* handle_area() const { return _handle_area; }
488 void set_handle_area(HandleArea* area) { _handle_area = area; }
489
490 GrowableArray<Metadata*>* metadata_handles() const { return _metadata_handles; }
491 void set_metadata_handles(GrowableArray<Metadata*>* handles){ _metadata_handles = handles; }
492
493 // Thread-Local Allocation Buffer (TLAB) support
494 ThreadLocalAllocBuffer& tlab() { return _tlab; }
495 void initialize_tlab() {
496 if (UseTLAB) {
497 tlab().initialize();
498 }
499 }
500
501 jlong allocated_bytes() { return _allocated_bytes; }
502 void set_allocated_bytes(jlong value) { _allocated_bytes = value; }
503 void incr_allocated_bytes(jlong size) { _allocated_bytes += size; }
504 inline jlong cooked_allocated_bytes();
505
506 ThreadHeapSampler& heap_sampler() { return _heap_sampler; }
507
508 TRACE_DEFINE_THREAD_TRACE_DATA_OFFSET;
509 TRACE_DATA* trace_data() const { return &_trace_data; }
510 bool is_trace_suspend() { return (_suspend_flags & _trace_flag) != 0; }
511
512 // VM operation support
513 int vm_operation_ticket() { return ++_vm_operation_started_count; }
514 int vm_operation_completed_count() { return _vm_operation_completed_count; }
515 void increment_vm_operation_completed_count() { _vm_operation_completed_count++; }
516
517 // For tracking the heavyweight monitor the thread is pending on.
518 ObjectMonitor* current_pending_monitor() {
519 return _current_pending_monitor;
520 }
521 void set_current_pending_monitor(ObjectMonitor* monitor) {
522 _current_pending_monitor = monitor;
523 }
524 void set_current_pending_monitor_is_from_java(bool from_java) {
525 _current_pending_monitor_is_from_java = from_java;
526 }
527 bool current_pending_monitor_is_from_java() {
528 return _current_pending_monitor_is_from_java;
529 }
530
531 // For tracking the ObjectMonitor on which this thread called Object.wait()
532 ObjectMonitor* current_waiting_monitor() {
533 return _current_waiting_monitor;
534 }
535 void set_current_waiting_monitor(ObjectMonitor* monitor) {
536 _current_waiting_monitor = monitor;
537 }
538
539 // GC support
540 // Apply "f->do_oop" to all root oops in "this".
541 // Used by JavaThread::oops_do.
542 // Apply "cf->do_code_blob" (if !NULL) to all code blobs active in frames
543 virtual void oops_do(OopClosure* f, CodeBlobClosure* cf);
544
545 // Handles the parallel case for the method below.
546 private:
547 bool claim_oops_do_par_case(int collection_parity);
548 public:
549 // Requires that "collection_parity" is that of the current roots
550 // iteration. If "is_par" is false, sets the parity of "this" to
551 // "collection_parity", and returns "true". If "is_par" is true,
552 // uses an atomic instruction to set the current threads parity to
553 // "collection_parity", if it is not already. Returns "true" iff the
554 // calling thread does the update, this indicates that the calling thread
555 // has claimed the thread's stack as a root groop in the current
556 // collection.
557 bool claim_oops_do(bool is_par, int collection_parity) {
558 if (!is_par) {
559 _oops_do_parity = collection_parity;
560 return true;
561 } else {
562 return claim_oops_do_par_case(collection_parity);
563 }
564 }
565
566 // jvmtiRedefineClasses support
567 void metadata_handles_do(void f(Metadata*));
568
569 // Used by fast lock support
570 virtual bool is_lock_owned(address adr) const;
571
572 // Check if address is in the stack of the thread (not just for locks).
573 // Warning: the method can only be used on the running thread
574 bool is_in_stack(address adr) const;
575 // Check if address is in the usable part of the stack (excludes protected
576 // guard pages)
577 bool is_in_usable_stack(address adr) const;
578
579 // Sets this thread as starting thread. Returns failure if thread
580 // creation fails due to lack of memory, too many threads etc.
581 bool set_as_starting_thread();
582
583 protected:
584 // OS data associated with the thread
585 OSThread* _osthread; // Platform-specific thread information
586
587 // Thread local resource area for temporary allocation within the VM
588 ResourceArea* _resource_area;
589
590 DEBUG_ONLY(ResourceMark* _current_resource_mark;)
591
592 // Thread local handle area for allocation of handles within the VM
593 HandleArea* _handle_area;
594 GrowableArray<Metadata*>* _metadata_handles;
595
596 // Support for stack overflow handling, get_thread, etc.
597 address _stack_base;
598 size_t _stack_size;
599 uintptr_t _self_raw_id; // used by get_thread (mutable)
600 int _lgrp_id;
601
602 volatile void** polling_page_addr() { return &_polling_page; }
603
604 public:
605 // Stack overflow support
606 address stack_base() const { assert(_stack_base != NULL,"Sanity check"); return _stack_base; }
607 void set_stack_base(address base) { _stack_base = base; }
608 size_t stack_size() const { return _stack_size; }
609 void set_stack_size(size_t size) { _stack_size = size; }
610 address stack_end() const { return stack_base() - stack_size(); }
611 void record_stack_base_and_size();
612
613 bool on_local_stack(address adr) const {
614 // QQQ this has knowledge of direction, ought to be a stack method
615 return (_stack_base >= adr && adr >= stack_end());
616 }
617
618 uintptr_t self_raw_id() { return _self_raw_id; }
619 void set_self_raw_id(uintptr_t value) { _self_raw_id = value; }
620
621 int lgrp_id() const { return _lgrp_id; }
622 void set_lgrp_id(int value) { _lgrp_id = value; }
623
624 // Printing
625 virtual void print_on(outputStream* st) const;
626 virtual void print_nested_threads_hazard_ptrs_on(outputStream* st) const;
627 void print() const { print_on(tty); }
628 virtual void print_on_error(outputStream* st, char* buf, int buflen) const;
629 void print_value_on(outputStream* st) const;
630
631 // Debug-only code
632 #ifdef ASSERT
633 private:
634 // Deadlock detection support for Mutex locks. List of locks own by thread.
635 Monitor* _owned_locks;
636 // Mutex::set_owner_implementation is the only place where _owned_locks is modified,
637 // thus the friendship
638 friend class Mutex;
639 friend class Monitor;
640
641 public:
642 void print_owned_locks_on(outputStream* st) const;
643 void print_owned_locks() const { print_owned_locks_on(tty); }
644 Monitor* owned_locks() const { return _owned_locks; }
645 bool owns_locks() const { return owned_locks() != NULL; }
646 bool owns_locks_but_compiled_lock() const;
647 int oops_do_parity() const { return _oops_do_parity; }
648
649 // Deadlock detection
650 bool allow_allocation() { return _allow_allocation_count == 0; }
651 ResourceMark* current_resource_mark() { return _current_resource_mark; }
652 void set_current_resource_mark(ResourceMark* rm) { _current_resource_mark = rm; }
653 #endif
654
655 void check_for_valid_safepoint_state(bool potential_vm_operation) PRODUCT_RETURN;
656
657 private:
658 volatile int _jvmti_env_iteration_count;
659
660 public:
661 void entering_jvmti_env_iteration() { ++_jvmti_env_iteration_count; }
662 void leaving_jvmti_env_iteration() { --_jvmti_env_iteration_count; }
663 bool is_inside_jvmti_env_iteration() { return _jvmti_env_iteration_count > 0; }
664
665 // Code generation
666 static ByteSize exception_file_offset() { return byte_offset_of(Thread, _exception_file); }
667 static ByteSize exception_line_offset() { return byte_offset_of(Thread, _exception_line); }
668 static ByteSize active_handles_offset() { return byte_offset_of(Thread, _active_handles); }
669
670 static ByteSize stack_base_offset() { return byte_offset_of(Thread, _stack_base); }
671 static ByteSize stack_size_offset() { return byte_offset_of(Thread, _stack_size); }
672
673 static ByteSize polling_page_offset() { return byte_offset_of(Thread, _polling_page); }
674
675 #define TLAB_FIELD_OFFSET(name) \
676 static ByteSize tlab_##name##_offset() { return byte_offset_of(Thread, _tlab) + ThreadLocalAllocBuffer::name##_offset(); }
677
678 TLAB_FIELD_OFFSET(start)
679 TLAB_FIELD_OFFSET(fast_path_end)
680 TLAB_FIELD_OFFSET(top)
681 TLAB_FIELD_OFFSET(pf_top)
682 TLAB_FIELD_OFFSET(size) // desired_size
683 TLAB_FIELD_OFFSET(refill_waste_limit)
684 TLAB_FIELD_OFFSET(number_of_refills)
685 TLAB_FIELD_OFFSET(fast_refill_waste)
686 TLAB_FIELD_OFFSET(slow_allocations)
687
688 #undef TLAB_FIELD_OFFSET
689
690 static ByteSize allocated_bytes_offset() { return byte_offset_of(Thread, _allocated_bytes); }
691
692 public:
693 volatile intptr_t _Stalled;
694 volatile int _TypeTag;
695 ParkEvent * _ParkEvent; // for synchronized()
696 ParkEvent * _SleepEvent; // for Thread.sleep
697 ParkEvent * _MutexEvent; // for native internal Mutex/Monitor
698 ParkEvent * _MuxEvent; // for low-level muxAcquire-muxRelease
699 int NativeSyncRecursion; // diagnostic
700
701 volatile int _OnTrap; // Resume-at IP delta
702 jint _hashStateW; // Marsaglia Shift-XOR thread-local RNG
703 jint _hashStateX; // thread-specific hashCode generator state
704 jint _hashStateY;
705 jint _hashStateZ;
706 void * _schedctl;
707
708
709 volatile jint rng[4]; // RNG for spin loop
710
711 // Low-level leaf-lock primitives used to implement synchronization
712 // and native monitor-mutex infrastructure.
713 // Not for general synchronization use.
714 static void SpinAcquire(volatile int * Lock, const char * Name);
715 static void SpinRelease(volatile int * Lock);
716 static void muxAcquire(volatile intptr_t * Lock, const char * Name);
717 static void muxAcquireW(volatile intptr_t * Lock, ParkEvent * ev);
718 static void muxRelease(volatile intptr_t * Lock);
719 };
720
721 // Inline implementation of Thread::current()
722 inline Thread* Thread::current() {
723 Thread* current = current_or_null();
724 assert(current != NULL, "Thread::current() called on detached thread");
725 return current;
726 }
727
728 inline Thread* Thread::current_or_null() {
729 #ifndef USE_LIBRARY_BASED_TLS_ONLY
730 return _thr_current;
731 #else
732 if (ThreadLocalStorage::is_initialized()) {
733 return ThreadLocalStorage::thread();
734 }
735 return NULL;
736 #endif
737 }
738
739 inline Thread* Thread::current_or_null_safe() {
740 if (ThreadLocalStorage::is_initialized()) {
741 return ThreadLocalStorage::thread();
742 }
743 return NULL;
744 }
745
746 // Name support for threads. non-JavaThread subclasses with multiple
747 // uniquely named instances should derive from this.
748 class NamedThread: public Thread {
749 friend class VMStructs;
750 enum {
751 max_name_len = 64
752 };
753 private:
754 char* _name;
755 // log JavaThread being processed by oops_do
756 JavaThread* _processed_thread;
757 uint _gc_id; // The current GC id when a thread takes part in GC
758
759 public:
760 NamedThread();
761 ~NamedThread();
762 // May only be called once per thread.
763 void set_name(const char* format, ...) ATTRIBUTE_PRINTF(2, 3);
764 void initialize_named_thread();
765 virtual bool is_Named_thread() const { return true; }
766 virtual char* name() const { return _name == NULL ? (char*)"Unknown Thread" : _name; }
767 JavaThread *processed_thread() { return _processed_thread; }
768 void set_processed_thread(JavaThread *thread) { _processed_thread = thread; }
769 virtual void print_on(outputStream* st) const;
770
771 void set_gc_id(uint gc_id) { _gc_id = gc_id; }
772 uint gc_id() { return _gc_id; }
773 };
774
775 // Worker threads are named and have an id of an assigned work.
776 class WorkerThread: public NamedThread {
777 private:
778 uint _id;
779 public:
780 WorkerThread() : _id(0) { }
781 virtual bool is_Worker_thread() const { return true; }
782
783 virtual WorkerThread* as_Worker_thread() const {
784 assert(is_Worker_thread(), "Dubious cast to WorkerThread*?");
785 return (WorkerThread*) this;
786 }
787
788 void set_id(uint work_id) { _id = work_id; }
789 uint id() const { return _id; }
790 };
791
792 // A single WatcherThread is used for simulating timer interrupts.
793 class WatcherThread: public Thread {
794 friend class VMStructs;
795 public:
796 virtual void run();
797
798 private:
799 static WatcherThread* _watcher_thread;
800
801 static bool _startable;
802 // volatile due to at least one lock-free read
803 volatile static bool _should_terminate;
804 public:
805 enum SomeConstants {
806 delay_interval = 10 // interrupt delay in milliseconds
807 };
808
809 // Constructor
810 WatcherThread();
811
812 // No destruction allowed
813 ~WatcherThread() {
814 guarantee(false, "WatcherThread deletion must fix the race with VM termination");
815 }
816
817 // Tester
818 bool is_Watcher_thread() const { return true; }
819
820 // Printing
821 char* name() const { return (char*)"VM Periodic Task Thread"; }
822 void print_on(outputStream* st) const;
823 void unpark();
824
825 // Returns the single instance of WatcherThread
826 static WatcherThread* watcher_thread() { return _watcher_thread; }
827
828 // Create and start the single instance of WatcherThread, or stop it on shutdown
829 static void start();
830 static void stop();
831 // Only allow start once the VM is sufficiently initialized
832 // Otherwise the first task to enroll will trigger the start
833 static void make_startable();
834 private:
835 int sleep() const;
836 };
837
838
839 class CompilerThread;
840
841 typedef void (*ThreadFunction)(JavaThread*, TRAPS);
842
843 class JavaThread: public Thread {
844 friend class VMStructs;
845 friend class JVMCIVMStructs;
846 friend class WhiteBox;
847 private:
848 JavaThread* _next; // The next thread in the Threads list
849 bool _on_thread_list; // Is set when this JavaThread is added to the Threads list
850 oop _threadObj; // The Java level thread object
851
852 #ifdef ASSERT
853 private:
854 int _java_call_counter;
855
856 public:
857 int java_call_counter() { return _java_call_counter; }
858 void inc_java_call_counter() { _java_call_counter++; }
859 void dec_java_call_counter() {
860 assert(_java_call_counter > 0, "Invalid nesting of JavaCallWrapper");
861 _java_call_counter--;
862 }
863 private: // restore original namespace restriction
864 #endif // ifdef ASSERT
865
866 #ifndef PRODUCT
867 public:
868 enum {
869 jump_ring_buffer_size = 16
870 };
871 private: // restore original namespace restriction
872 #endif
873
874 JavaFrameAnchor _anchor; // Encapsulation of current java frame and it state
875
876 ThreadFunction _entry_point;
877
878 JNIEnv _jni_environment;
879
880 // Deopt support
881 DeoptResourceMark* _deopt_mark; // Holds special ResourceMark for deoptimization
882
883 intptr_t* _must_deopt_id; // id of frame that needs to be deopted once we
884 // transition out of native
885 CompiledMethod* _deopt_nmethod; // CompiledMethod that is currently being deoptimized
886 vframeArray* _vframe_array_head; // Holds the heap of the active vframeArrays
887 vframeArray* _vframe_array_last; // Holds last vFrameArray we popped
888 // Because deoptimization is lazy we must save jvmti requests to set locals
889 // in compiled frames until we deoptimize and we have an interpreter frame.
890 // This holds the pointer to array (yeah like there might be more than one) of
891 // description of compiled vframes that have locals that need to be updated.
892 GrowableArray<jvmtiDeferredLocalVariableSet*>* _deferred_locals_updates;
893
894 // Handshake value for fixing 6243940. We need a place for the i2c
895 // adapter to store the callee Method*. This value is NEVER live
896 // across a gc point so it does NOT have to be gc'd
897 // The handshake is open ended since we can't be certain that it will
898 // be NULLed. This is because we rarely ever see the race and end up
899 // in handle_wrong_method which is the backend of the handshake. See
900 // code in i2c adapters and handle_wrong_method.
901
902 Method* _callee_target;
903
904 // Used to pass back results to the interpreter or generated code running Java code.
905 oop _vm_result; // oop result is GC-preserved
906 Metadata* _vm_result_2; // non-oop result
907
908 // See ReduceInitialCardMarks: this holds the precise space interval of
909 // the most recent slow path allocation for which compiled code has
910 // elided card-marks for performance along the fast-path.
911 MemRegion _deferred_card_mark;
912
913 MonitorChunk* _monitor_chunks; // Contains the off stack monitors
914 // allocated during deoptimization
915 // and by JNI_MonitorEnter/Exit
916
917 // Async. requests support
918 enum AsyncRequests {
919 _no_async_condition = 0,
920 _async_exception,
921 _async_unsafe_access_error
922 };
923 AsyncRequests _special_runtime_exit_condition; // Enum indicating pending async. request
924 oop _pending_async_exception;
925
926 // Safepoint support
927 public: // Expose _thread_state for SafeFetchInt()
928 volatile JavaThreadState _thread_state;
929 private:
930 ThreadSafepointState *_safepoint_state; // Holds information about a thread during a safepoint
931 address _saved_exception_pc; // Saved pc of instruction where last implicit exception happened
932
933 // JavaThread termination support
934 enum TerminatedTypes {
935 _not_terminated = 0xDEAD - 2,
936 _thread_exiting, // JavaThread::exit() has been called for this thread
937 _thread_terminated, // JavaThread is removed from thread list
938 _vm_exited // JavaThread is still executing native code, but VM is terminated
939 // only VM_Exit can set _vm_exited
940 };
941
942 // In general a JavaThread's _terminated field transitions as follows:
943 //
944 // _not_terminated => _thread_exiting => _thread_terminated
945 //
946 // _vm_exited is a special value to cover the case of a JavaThread
947 // executing native code after the VM itself is terminated.
948 volatile TerminatedTypes _terminated;
949 // suspend/resume support
950 volatile bool _suspend_equivalent; // Suspend equivalent condition
951 jint _in_deopt_handler; // count of deoptimization
952 // handlers thread is in
953 volatile bool _doing_unsafe_access; // Thread may fault due to unsafe access
954 bool _do_not_unlock_if_synchronized; // Do not unlock the receiver of a synchronized method (since it was
955 // never locked) when throwing an exception. Used by interpreter only.
956
957 // JNI attach states:
958 enum JNIAttachStates {
959 _not_attaching_via_jni = 1, // thread is not attaching via JNI
960 _attaching_via_jni, // thread is attaching via JNI
961 _attached_via_jni // thread has attached via JNI
962 };
963
964 // A regular JavaThread's _jni_attach_state is _not_attaching_via_jni.
965 // A native thread that is attaching via JNI starts with a value
966 // of _attaching_via_jni and transitions to _attached_via_jni.
967 volatile JNIAttachStates _jni_attach_state;
968
969 public:
970 // State of the stack guard pages for this thread.
971 enum StackGuardState {
972 stack_guard_unused, // not needed
973 stack_guard_reserved_disabled,
974 stack_guard_yellow_reserved_disabled,// disabled (temporarily) after stack overflow
975 stack_guard_enabled // enabled
976 };
977
978 private:
979
980 #if INCLUDE_JVMCI
981 // The _pending_* fields below are used to communicate extra information
982 // from an uncommon trap in JVMCI compiled code to the uncommon trap handler.
983
984 // Communicates the DeoptReason and DeoptAction of the uncommon trap
985 int _pending_deoptimization;
986
987 // Specifies whether the uncommon trap is to bci 0 of a synchronized method
988 // before the monitor has been acquired.
989 bool _pending_monitorenter;
990
991 // Specifies if the DeoptReason for the last uncommon trap was Reason_transfer_to_interpreter
992 bool _pending_transfer_to_interpreter;
993
994 // Guard for re-entrant call to JVMCIRuntime::adjust_comp_level
995 bool _adjusting_comp_level;
996
997 // An object that JVMCI compiled code can use to further describe and
998 // uniquely identify the speculative optimization guarded by the uncommon trap
999 oop _pending_failed_speculation;
1000
1001 // These fields are mutually exclusive in terms of live ranges.
1002 union {
1003 // Communicates the pc at which the most recent implicit exception occurred
1004 // from the signal handler to a deoptimization stub.
1005 address _implicit_exception_pc;
1006
1007 // Communicates an alternative call target to an i2c stub from a JavaCall .
1008 address _alternate_call_target;
1009 } _jvmci;
1010
1011 // Support for high precision, thread sensitive counters in JVMCI compiled code.
1012 jlong* _jvmci_counters;
1013
1014 public:
1015 static jlong* _jvmci_old_thread_counters;
1016 static void collect_counters(typeArrayOop array);
1017 private:
1018 #endif // INCLUDE_JVMCI
1019
1020 StackGuardState _stack_guard_state;
1021
1022 // Precompute the limit of the stack as used in stack overflow checks.
1023 // We load it from here to simplify the stack overflow check in assembly.
1024 address _stack_overflow_limit;
1025 address _reserved_stack_activation;
1026
1027 // Compiler exception handling (NOTE: The _exception_oop is *NOT* the same as _pending_exception. It is
1028 // used to temp. parsing values into and out of the runtime system during exception handling for compiled
1029 // code)
1030 volatile oop _exception_oop; // Exception thrown in compiled code
1031 volatile address _exception_pc; // PC where exception happened
1032 volatile address _exception_handler_pc; // PC for handler of exception
1033 volatile int _is_method_handle_return; // true (== 1) if the current exception PC is a MethodHandle call site.
1034
1035 private:
1036 // support for JNI critical regions
1037 jint _jni_active_critical; // count of entries into JNI critical region
1038
1039 // Checked JNI: function name requires exception check
1040 char* _pending_jni_exception_check_fn;
1041
1042 // For deadlock detection.
1043 int _depth_first_number;
1044
1045 // JVMTI PopFrame support
1046 // This is set to popframe_pending to signal that top Java frame should be popped immediately
1047 int _popframe_condition;
1048
1049 // If reallocation of scalar replaced objects fails, we throw OOM
1050 // and during exception propagation, pop the top
1051 // _frames_to_pop_failed_realloc frames, the ones that reference
1052 // failed reallocations.
1053 int _frames_to_pop_failed_realloc;
1054
1055 #ifndef PRODUCT
1056 int _jmp_ring_index;
1057 struct {
1058 // We use intptr_t instead of address so debugger doesn't try and display strings
1059 intptr_t _target;
1060 intptr_t _instruction;
1061 const char* _file;
1062 int _line;
1063 } _jmp_ring[jump_ring_buffer_size];
1064 #endif // PRODUCT
1065
1066 #if INCLUDE_ALL_GCS
1067 // Support for G1 barriers
1068
1069 SATBMarkQueue _satb_mark_queue; // Thread-local log for SATB barrier.
1070 // Set of all such queues.
1071 static SATBMarkQueueSet _satb_mark_queue_set;
1072
1073 DirtyCardQueue _dirty_card_queue; // Thread-local log for dirty cards.
1074 // Set of all such queues.
1075 static DirtyCardQueueSet _dirty_card_queue_set;
1076 #endif // INCLUDE_ALL_GCS
1077
1078 friend class VMThread;
1079 friend class ThreadWaitTransition;
1080 friend class VM_Exit;
1081
1082 void initialize(); // Initialized the instance variables
1083
1084 public:
1085 // Constructor
1086 JavaThread(bool is_attaching_via_jni = false); // for main thread and JNI attached threads
1087 JavaThread(ThreadFunction entry_point, size_t stack_size = 0);
1088 ~JavaThread();
1089
1090 #ifdef ASSERT
1091 // verify this JavaThread hasn't be published in the Threads::list yet
1092 void verify_not_published();
1093 #endif
1094
1095 //JNI functiontable getter/setter for JVMTI jni function table interception API.
1096 void set_jni_functions(struct JNINativeInterface_* functionTable) {
1097 _jni_environment.functions = functionTable;
1098 }
1099 struct JNINativeInterface_* get_jni_functions() {
1100 return (struct JNINativeInterface_ *)_jni_environment.functions;
1101 }
1102
1103 // This function is called at thread creation to allow
1104 // platform specific thread variables to be initialized.
1105 void cache_global_variables();
1106
1107 // Executes Shutdown.shutdown()
1108 void invoke_shutdown_hooks();
1109
1110 // Cleanup on thread exit
1111 enum ExitType {
1112 normal_exit,
1113 jni_detach
1114 };
1115 void exit(bool destroy_vm, ExitType exit_type = normal_exit);
1116
1117 void cleanup_failed_attach_current_thread();
1118
1119 // Testers
1120 virtual bool is_Java_thread() const { return true; }
1121 virtual bool can_call_java() const { return true; }
1122
1123 // Thread chain operations
1124 JavaThread* next() const { return _next; }
1125 void set_next(JavaThread* p) { _next = p; }
1126
1127 // Thread oop. threadObj() can be NULL for initial JavaThread
1128 // (or for threads attached via JNI)
1129 oop threadObj() const { return _threadObj; }
1130 void set_threadObj(oop p) { _threadObj = p; }
1131
1132 ThreadPriority java_priority() const; // Read from threadObj()
1133
1134 // Prepare thread and add to priority queue. If a priority is
1135 // not specified, use the priority of the thread object. Threads_lock
1136 // must be held while this function is called.
1137 void prepare(jobject jni_thread, ThreadPriority prio=NoPriority);
1138
1139 void set_saved_exception_pc(address pc) { _saved_exception_pc = pc; }
1140 address saved_exception_pc() { return _saved_exception_pc; }
1141
1142
1143 ThreadFunction entry_point() const { return _entry_point; }
1144
1145 // Allocates a new Java level thread object for this thread. thread_name may be NULL.
1146 void allocate_threadObj(Handle thread_group, const char* thread_name, bool daemon, TRAPS);
1147
1148 // Last frame anchor routines
1149
1150 JavaFrameAnchor* frame_anchor(void) { return &_anchor; }
1151
1152 // last_Java_sp
1153 bool has_last_Java_frame() const { return _anchor.has_last_Java_frame(); }
1154 intptr_t* last_Java_sp() const { return _anchor.last_Java_sp(); }
1155
1156 // last_Java_pc
1157
1158 address last_Java_pc(void) { return _anchor.last_Java_pc(); }
1159
1160 // Safepoint support
1161 #if !(defined(PPC64) || defined(AARCH64))
1162 JavaThreadState thread_state() const { return _thread_state; }
1163 void set_thread_state(JavaThreadState s) { _thread_state = s; }
1164 #else
1165 // Use membars when accessing volatile _thread_state. See
1166 // Threads::create_vm() for size checks.
1167 inline JavaThreadState thread_state() const;
1168 inline void set_thread_state(JavaThreadState s);
1169 #endif
1170 ThreadSafepointState *safepoint_state() const { return _safepoint_state; }
1171 void set_safepoint_state(ThreadSafepointState *state) { _safepoint_state = state; }
1172 bool is_at_poll_safepoint() { return _safepoint_state->is_at_poll_safepoint(); }
1173
1174 // JavaThread termination and lifecycle support:
1175 void smr_delete();
1176 bool on_thread_list() const { return _on_thread_list; }
1177 void set_on_thread_list() { _on_thread_list = true; }
1178
1179 // thread has called JavaThread::exit() or is terminated
1180 bool is_exiting() const;
1181 // thread is terminated (no longer on the threads list); we compare
1182 // against the two non-terminated values so that a freed JavaThread
1183 // will also be considered terminated.
1184 bool check_is_terminated(TerminatedTypes l_terminated) const {
1185 return l_terminated != _not_terminated && l_terminated != _thread_exiting;
1186 }
1187 bool is_terminated() const;
1188 void set_terminated(TerminatedTypes t);
1189 // special for Threads::remove() which is static:
1190 void set_terminated_value();
1191 void block_if_vm_exited();
1192
1193 bool doing_unsafe_access() { return _doing_unsafe_access; }
1194 void set_doing_unsafe_access(bool val) { _doing_unsafe_access = val; }
1195
1196 bool do_not_unlock_if_synchronized() { return _do_not_unlock_if_synchronized; }
1197 void set_do_not_unlock_if_synchronized(bool val) { _do_not_unlock_if_synchronized = val; }
1198
1199 inline void set_polling_page(void* poll_value);
1200 inline volatile void* get_polling_page();
1201
1202 private:
1203 // Support for thread handshake operations
1204 HandshakeState _handshake;
1205 public:
1206 void set_handshake_operation(HandshakeOperation* op) {
1207 _handshake.set_operation(this, op);
1208 }
1209
1210 bool has_handshake() const {
1211 return _handshake.has_operation();
1212 }
1213
1214 void cancel_handshake() {
1215 _handshake.cancel(this);
1216 }
1217
1218 void handshake_process_by_self() {
1219 _handshake.process_by_self(this);
1220 }
1221
1222 void handshake_process_by_vmthread() {
1223 _handshake.process_by_vmthread(this);
1224 }
1225
1226 // Suspend/resume support for JavaThread
1227 private:
1228 inline void set_ext_suspended();
1229 inline void clear_ext_suspended();
1230
1231 public:
1232 void java_suspend();
1233 void java_resume();
1234 int java_suspend_self();
1235
1236 void check_and_wait_while_suspended() {
1237 assert(JavaThread::current() == this, "sanity check");
1238
1239 bool do_self_suspend;
1240 do {
1241 // were we externally suspended while we were waiting?
1242 do_self_suspend = handle_special_suspend_equivalent_condition();
1243 if (do_self_suspend) {
1244 // don't surprise the thread that suspended us by returning
1245 java_suspend_self();
1246 set_suspend_equivalent();
1247 }
1248 } while (do_self_suspend);
1249 }
1250 static void check_safepoint_and_suspend_for_native_trans(JavaThread *thread);
1251 // Check for async exception in addition to safepoint and suspend request.
1252 static void check_special_condition_for_native_trans(JavaThread *thread);
1253
1254 // Same as check_special_condition_for_native_trans but finishes the
1255 // transition into thread_in_Java mode so that it can potentially
1256 // block.
1257 static void check_special_condition_for_native_trans_and_transition(JavaThread *thread);
1258
1259 bool is_ext_suspend_completed(bool called_by_wait, int delay, uint32_t *bits);
1260 bool is_ext_suspend_completed_with_lock(uint32_t *bits) {
1261 MutexLockerEx ml(SR_lock(), Mutex::_no_safepoint_check_flag);
1262 // Warning: is_ext_suspend_completed() may temporarily drop the
1263 // SR_lock to allow the thread to reach a stable thread state if
1264 // it is currently in a transient thread state.
1265 return is_ext_suspend_completed(false /* !called_by_wait */,
1266 SuspendRetryDelay, bits);
1267 }
1268
1269 // We cannot allow wait_for_ext_suspend_completion() to run forever or
1270 // we could hang. SuspendRetryCount and SuspendRetryDelay are normally
1271 // passed as the count and delay parameters. Experiments with specific
1272 // calls to wait_for_ext_suspend_completion() can be done by passing
1273 // other values in the code. Experiments with all calls can be done
1274 // via the appropriate -XX options.
1275 bool wait_for_ext_suspend_completion(int count, int delay, uint32_t *bits);
1276
1277 // test for suspend - most (all?) of these should go away
1278 bool is_thread_fully_suspended(bool wait_for_suspend, uint32_t *bits);
1279
1280 inline void set_external_suspend();
1281 inline void clear_external_suspend();
1282
1283 inline void set_deopt_suspend();
1284 inline void clear_deopt_suspend();
1285 bool is_deopt_suspend() { return (_suspend_flags & _deopt_suspend) != 0; }
1286
1287 bool is_external_suspend() const {
1288 return (_suspend_flags & _external_suspend) != 0;
1289 }
1290 // Whenever a thread transitions from native to vm/java it must suspend
1291 // if external|deopt suspend is present.
1292 bool is_suspend_after_native() const {
1293 return (_suspend_flags & (_external_suspend | _deopt_suspend)) != 0;
1294 }
1295
1296 // external suspend request is completed
1297 bool is_ext_suspended() const {
1298 return (_suspend_flags & _ext_suspended) != 0;
1299 }
1300
1301 bool is_external_suspend_with_lock() const {
1302 MutexLockerEx ml(SR_lock(), Mutex::_no_safepoint_check_flag);
1303 return is_external_suspend();
1304 }
1305
1306 // Special method to handle a pending external suspend request
1307 // when a suspend equivalent condition lifts.
1308 bool handle_special_suspend_equivalent_condition() {
1309 assert(is_suspend_equivalent(),
1310 "should only be called in a suspend equivalence condition");
1311 MutexLockerEx ml(SR_lock(), Mutex::_no_safepoint_check_flag);
1312 bool ret = is_external_suspend();
1313 if (!ret) {
1314 // not about to self-suspend so clear suspend equivalence
1315 clear_suspend_equivalent();
1316 }
1317 // implied else:
1318 // We have a pending external suspend request so we leave the
1319 // suspend_equivalent flag set until java_suspend_self() sets
1320 // the ext_suspended flag and clears the suspend_equivalent
1321 // flag. This insures that wait_for_ext_suspend_completion()
1322 // will return consistent values.
1323 return ret;
1324 }
1325
1326 // utility methods to see if we are doing some kind of suspension
1327 bool is_being_ext_suspended() const {
1328 MutexLockerEx ml(SR_lock(), Mutex::_no_safepoint_check_flag);
1329 return is_ext_suspended() || is_external_suspend();
1330 }
1331
1332 bool is_suspend_equivalent() const { return _suspend_equivalent; }
1333
1334 void set_suspend_equivalent() { _suspend_equivalent = true; }
1335 void clear_suspend_equivalent() { _suspend_equivalent = false; }
1336
1337 // Thread.stop support
1338 void send_thread_stop(oop throwable);
1339 AsyncRequests clear_special_runtime_exit_condition() {
1340 AsyncRequests x = _special_runtime_exit_condition;
1341 _special_runtime_exit_condition = _no_async_condition;
1342 return x;
1343 }
1344
1345 // Are any async conditions present?
1346 bool has_async_condition() { return (_special_runtime_exit_condition != _no_async_condition); }
1347
1348 void check_and_handle_async_exceptions(bool check_unsafe_error = true);
1349
1350 // these next two are also used for self-suspension and async exception support
1351 void handle_special_runtime_exit_condition(bool check_asyncs = true);
1352
1353 // Return true if JavaThread has an asynchronous condition or
1354 // if external suspension is requested.
1355 bool has_special_runtime_exit_condition() {
1356 // Because we don't use is_external_suspend_with_lock
1357 // it is possible that we won't see an asynchronous external suspend
1358 // request that has just gotten started, i.e., SR_lock grabbed but
1359 // _external_suspend field change either not made yet or not visible
1360 // yet. However, this is okay because the request is asynchronous and
1361 // we will see the new flag value the next time through. It's also
1362 // possible that the external suspend request is dropped after
1363 // we have checked is_external_suspend(), we will recheck its value
1364 // under SR_lock in java_suspend_self().
1365 return (_special_runtime_exit_condition != _no_async_condition) ||
1366 is_external_suspend() || is_trace_suspend();
1367 }
1368
1369 void set_pending_unsafe_access_error() { _special_runtime_exit_condition = _async_unsafe_access_error; }
1370
1371 inline void set_pending_async_exception(oop e);
1372
1373 // Fast-locking support
1374 bool is_lock_owned(address adr) const;
1375
1376 // Accessors for vframe array top
1377 // The linked list of vframe arrays are sorted on sp. This means when we
1378 // unpack the head must contain the vframe array to unpack.
1379 void set_vframe_array_head(vframeArray* value) { _vframe_array_head = value; }
1380 vframeArray* vframe_array_head() const { return _vframe_array_head; }
1381
1382 // Side structure for deferring update of java frame locals until deopt occurs
1383 GrowableArray<jvmtiDeferredLocalVariableSet*>* deferred_locals() const { return _deferred_locals_updates; }
1384 void set_deferred_locals(GrowableArray<jvmtiDeferredLocalVariableSet *>* vf) { _deferred_locals_updates = vf; }
1385
1386 // These only really exist to make debugging deopt problems simpler
1387
1388 void set_vframe_array_last(vframeArray* value) { _vframe_array_last = value; }
1389 vframeArray* vframe_array_last() const { return _vframe_array_last; }
1390
1391 // The special resourceMark used during deoptimization
1392
1393 void set_deopt_mark(DeoptResourceMark* value) { _deopt_mark = value; }
1394 DeoptResourceMark* deopt_mark(void) { return _deopt_mark; }
1395
1396 intptr_t* must_deopt_id() { return _must_deopt_id; }
1397 void set_must_deopt_id(intptr_t* id) { _must_deopt_id = id; }
1398 void clear_must_deopt_id() { _must_deopt_id = NULL; }
1399
1400 void set_deopt_compiled_method(CompiledMethod* nm) { _deopt_nmethod = nm; }
1401 CompiledMethod* deopt_compiled_method() { return _deopt_nmethod; }
1402
1403 Method* callee_target() const { return _callee_target; }
1404 void set_callee_target (Method* x) { _callee_target = x; }
1405
1406 // Oop results of vm runtime calls
1407 oop vm_result() const { return _vm_result; }
1408 void set_vm_result (oop x) { _vm_result = x; }
1409
1410 Metadata* vm_result_2() const { return _vm_result_2; }
1411 void set_vm_result_2 (Metadata* x) { _vm_result_2 = x; }
1412
1413 MemRegion deferred_card_mark() const { return _deferred_card_mark; }
1414 void set_deferred_card_mark(MemRegion mr) { _deferred_card_mark = mr; }
1415
1416 #if INCLUDE_JVMCI
1417 int pending_deoptimization() const { return _pending_deoptimization; }
1418 oop pending_failed_speculation() const { return _pending_failed_speculation; }
1419 bool adjusting_comp_level() const { return _adjusting_comp_level; }
1420 void set_adjusting_comp_level(bool b) { _adjusting_comp_level = b; }
1421 bool has_pending_monitorenter() const { return _pending_monitorenter; }
1422 void set_pending_monitorenter(bool b) { _pending_monitorenter = b; }
1423 void set_pending_deoptimization(int reason) { _pending_deoptimization = reason; }
1424 void set_pending_failed_speculation(oop failed_speculation) { _pending_failed_speculation = failed_speculation; }
1425 void set_pending_transfer_to_interpreter(bool b) { _pending_transfer_to_interpreter = b; }
1426 void set_jvmci_alternate_call_target(address a) { assert(_jvmci._alternate_call_target == NULL, "must be"); _jvmci._alternate_call_target = a; }
1427 void set_jvmci_implicit_exception_pc(address a) { assert(_jvmci._implicit_exception_pc == NULL, "must be"); _jvmci._implicit_exception_pc = a; }
1428 #endif // INCLUDE_JVMCI
1429
1430 // Exception handling for compiled methods
1431 oop exception_oop() const { return _exception_oop; }
1432 address exception_pc() const { return _exception_pc; }
1433 address exception_handler_pc() const { return _exception_handler_pc; }
1434 bool is_method_handle_return() const { return _is_method_handle_return == 1; }
1435
1436 void set_exception_oop(oop o) { (void)const_cast<oop&>(_exception_oop = o); }
1437 void set_exception_pc(address a) { _exception_pc = a; }
1438 void set_exception_handler_pc(address a) { _exception_handler_pc = a; }
1439 void set_is_method_handle_return(bool value) { _is_method_handle_return = value ? 1 : 0; }
1440
1441 void clear_exception_oop_and_pc() {
1442 set_exception_oop(NULL);
1443 set_exception_pc(NULL);
1444 }
1445
1446 // Stack overflow support
1447 //
1448 // (small addresses)
1449 //
1450 // -- <-- stack_end() ---
1451 // | |
1452 // | red pages |
1453 // | |
1454 // -- <-- stack_red_zone_base() |
1455 // | |
1456 // | guard
1457 // | yellow pages zone
1458 // | |
1459 // | |
1460 // -- <-- stack_yellow_zone_base() |
1461 // | |
1462 // | |
1463 // | reserved pages |
1464 // | |
1465 // -- <-- stack_reserved_zone_base() --- ---
1466 // /|\ shadow <-- stack_overflow_limit() (somewhere in here)
1467 // | zone
1468 // \|/ size
1469 // some untouched memory ---
1470 //
1471 //
1472 // --
1473 // |
1474 // | shadow zone
1475 // |
1476 // --
1477 // x frame n
1478 // --
1479 // x frame n-1
1480 // x
1481 // --
1482 // ...
1483 //
1484 // --
1485 // x frame 0
1486 // -- <-- stack_base()
1487 //
1488 // (large addresses)
1489 //
1490
1491 private:
1492 // These values are derived from flags StackRedPages, StackYellowPages,
1493 // StackReservedPages and StackShadowPages. The zone size is determined
1494 // ergonomically if page_size > 4K.
1495 static size_t _stack_red_zone_size;
1496 static size_t _stack_yellow_zone_size;
1497 static size_t _stack_reserved_zone_size;
1498 static size_t _stack_shadow_zone_size;
1499 public:
1500 inline size_t stack_available(address cur_sp);
1501
1502 static size_t stack_red_zone_size() {
1503 assert(_stack_red_zone_size > 0, "Don't call this before the field is initialized.");
1504 return _stack_red_zone_size;
1505 }
1506 static void set_stack_red_zone_size(size_t s) {
1507 assert(is_aligned(s, os::vm_page_size()),
1508 "We can not protect if the red zone size is not page aligned.");
1509 assert(_stack_red_zone_size == 0, "This should be called only once.");
1510 _stack_red_zone_size = s;
1511 }
1512 address stack_red_zone_base() {
1513 return (address)(stack_end() + stack_red_zone_size());
1514 }
1515 bool in_stack_red_zone(address a) {
1516 return a <= stack_red_zone_base() && a >= stack_end();
1517 }
1518
1519 static size_t stack_yellow_zone_size() {
1520 assert(_stack_yellow_zone_size > 0, "Don't call this before the field is initialized.");
1521 return _stack_yellow_zone_size;
1522 }
1523 static void set_stack_yellow_zone_size(size_t s) {
1524 assert(is_aligned(s, os::vm_page_size()),
1525 "We can not protect if the yellow zone size is not page aligned.");
1526 assert(_stack_yellow_zone_size == 0, "This should be called only once.");
1527 _stack_yellow_zone_size = s;
1528 }
1529
1530 static size_t stack_reserved_zone_size() {
1531 // _stack_reserved_zone_size may be 0. This indicates the feature is off.
1532 return _stack_reserved_zone_size;
1533 }
1534 static void set_stack_reserved_zone_size(size_t s) {
1535 assert(is_aligned(s, os::vm_page_size()),
1536 "We can not protect if the reserved zone size is not page aligned.");
1537 assert(_stack_reserved_zone_size == 0, "This should be called only once.");
1538 _stack_reserved_zone_size = s;
1539 }
1540 address stack_reserved_zone_base() {
1541 return (address)(stack_end() +
1542 (stack_red_zone_size() + stack_yellow_zone_size() + stack_reserved_zone_size()));
1543 }
1544 bool in_stack_reserved_zone(address a) {
1545 return (a <= stack_reserved_zone_base()) &&
1546 (a >= (address)((intptr_t)stack_reserved_zone_base() - stack_reserved_zone_size()));
1547 }
1548
1549 static size_t stack_yellow_reserved_zone_size() {
1550 return _stack_yellow_zone_size + _stack_reserved_zone_size;
1551 }
1552 bool in_stack_yellow_reserved_zone(address a) {
1553 return (a <= stack_reserved_zone_base()) && (a >= stack_red_zone_base());
1554 }
1555
1556 // Size of red + yellow + reserved zones.
1557 static size_t stack_guard_zone_size() {
1558 return stack_red_zone_size() + stack_yellow_reserved_zone_size();
1559 }
1560
1561 static size_t stack_shadow_zone_size() {
1562 assert(_stack_shadow_zone_size > 0, "Don't call this before the field is initialized.");
1563 return _stack_shadow_zone_size;
1564 }
1565 static void set_stack_shadow_zone_size(size_t s) {
1566 // The shadow area is not allocated or protected, so
1567 // it needs not be page aligned.
1568 // But the stack bang currently assumes that it is a
1569 // multiple of page size. This guarantees that the bang
1570 // loop touches all pages in the shadow zone.
1571 // This can be guaranteed differently, as well. E.g., if
1572 // the page size is a multiple of 4K, banging in 4K steps
1573 // suffices to touch all pages. (Some pages are banged
1574 // several times, though.)
1575 assert(is_aligned(s, os::vm_page_size()),
1576 "Stack bang assumes multiple of page size.");
1577 assert(_stack_shadow_zone_size == 0, "This should be called only once.");
1578 _stack_shadow_zone_size = s;
1579 }
1580
1581 void create_stack_guard_pages();
1582 void remove_stack_guard_pages();
1583
1584 void enable_stack_reserved_zone();
1585 void disable_stack_reserved_zone();
1586 void enable_stack_yellow_reserved_zone();
1587 void disable_stack_yellow_reserved_zone();
1588 void enable_stack_red_zone();
1589 void disable_stack_red_zone();
1590
1591 inline bool stack_guard_zone_unused();
1592 inline bool stack_yellow_reserved_zone_disabled();
1593 inline bool stack_reserved_zone_disabled();
1594 inline bool stack_guards_enabled();
1595
1596 address reserved_stack_activation() const { return _reserved_stack_activation; }
1597 void set_reserved_stack_activation(address addr) {
1598 assert(_reserved_stack_activation == stack_base()
1599 || _reserved_stack_activation == NULL
1600 || addr == stack_base(), "Must not be set twice");
1601 _reserved_stack_activation = addr;
1602 }
1603
1604 // Attempt to reguard the stack after a stack overflow may have occurred.
1605 // Returns true if (a) guard pages are not needed on this thread, (b) the
1606 // pages are already guarded, or (c) the pages were successfully reguarded.
1607 // Returns false if there is not enough stack space to reguard the pages, in
1608 // which case the caller should unwind a frame and try again. The argument
1609 // should be the caller's (approximate) sp.
1610 bool reguard_stack(address cur_sp);
1611 // Similar to above but see if current stackpoint is out of the guard area
1612 // and reguard if possible.
1613 bool reguard_stack(void);
1614
1615 address stack_overflow_limit() { return _stack_overflow_limit; }
1616 void set_stack_overflow_limit() {
1617 _stack_overflow_limit =
1618 stack_end() + MAX2(JavaThread::stack_guard_zone_size(), JavaThread::stack_shadow_zone_size());
1619 }
1620
1621 // Misc. accessors/mutators
1622 void set_do_not_unlock(void) { _do_not_unlock_if_synchronized = true; }
1623 void clr_do_not_unlock(void) { _do_not_unlock_if_synchronized = false; }
1624 bool do_not_unlock(void) { return _do_not_unlock_if_synchronized; }
1625
1626 #ifndef PRODUCT
1627 void record_jump(address target, address instr, const char* file, int line);
1628 #endif // PRODUCT
1629
1630 // For assembly stub generation
1631 static ByteSize threadObj_offset() { return byte_offset_of(JavaThread, _threadObj); }
1632 #ifndef PRODUCT
1633 static ByteSize jmp_ring_index_offset() { return byte_offset_of(JavaThread, _jmp_ring_index); }
1634 static ByteSize jmp_ring_offset() { return byte_offset_of(JavaThread, _jmp_ring); }
1635 #endif // PRODUCT
1636 static ByteSize jni_environment_offset() { return byte_offset_of(JavaThread, _jni_environment); }
1637 static ByteSize pending_jni_exception_check_fn_offset() {
1638 return byte_offset_of(JavaThread, _pending_jni_exception_check_fn);
1639 }
1640 static ByteSize last_Java_sp_offset() {
1641 return byte_offset_of(JavaThread, _anchor) + JavaFrameAnchor::last_Java_sp_offset();
1642 }
1643 static ByteSize last_Java_pc_offset() {
1644 return byte_offset_of(JavaThread, _anchor) + JavaFrameAnchor::last_Java_pc_offset();
1645 }
1646 static ByteSize frame_anchor_offset() {
1647 return byte_offset_of(JavaThread, _anchor);
1648 }
1649 static ByteSize callee_target_offset() { return byte_offset_of(JavaThread, _callee_target); }
1650 static ByteSize vm_result_offset() { return byte_offset_of(JavaThread, _vm_result); }
1651 static ByteSize vm_result_2_offset() { return byte_offset_of(JavaThread, _vm_result_2); }
1652 static ByteSize thread_state_offset() { return byte_offset_of(JavaThread, _thread_state); }
1653 static ByteSize saved_exception_pc_offset() { return byte_offset_of(JavaThread, _saved_exception_pc); }
1654 static ByteSize osthread_offset() { return byte_offset_of(JavaThread, _osthread); }
1655 #if INCLUDE_JVMCI
1656 static ByteSize pending_deoptimization_offset() { return byte_offset_of(JavaThread, _pending_deoptimization); }
1657 static ByteSize pending_monitorenter_offset() { return byte_offset_of(JavaThread, _pending_monitorenter); }
1658 static ByteSize pending_failed_speculation_offset() { return byte_offset_of(JavaThread, _pending_failed_speculation); }
1659 static ByteSize jvmci_alternate_call_target_offset() { return byte_offset_of(JavaThread, _jvmci._alternate_call_target); }
1660 static ByteSize jvmci_implicit_exception_pc_offset() { return byte_offset_of(JavaThread, _jvmci._implicit_exception_pc); }
1661 static ByteSize jvmci_counters_offset() { return byte_offset_of(JavaThread, _jvmci_counters); }
1662 #endif // INCLUDE_JVMCI
1663 static ByteSize exception_oop_offset() { return byte_offset_of(JavaThread, _exception_oop); }
1664 static ByteSize exception_pc_offset() { return byte_offset_of(JavaThread, _exception_pc); }
1665 static ByteSize exception_handler_pc_offset() { return byte_offset_of(JavaThread, _exception_handler_pc); }
1666 static ByteSize stack_overflow_limit_offset() { return byte_offset_of(JavaThread, _stack_overflow_limit); }
1667 static ByteSize is_method_handle_return_offset() { return byte_offset_of(JavaThread, _is_method_handle_return); }
1668 static ByteSize stack_guard_state_offset() { return byte_offset_of(JavaThread, _stack_guard_state); }
1669 static ByteSize reserved_stack_activation_offset() { return byte_offset_of(JavaThread, _reserved_stack_activation); }
1670 static ByteSize suspend_flags_offset() { return byte_offset_of(JavaThread, _suspend_flags); }
1671
1672 static ByteSize do_not_unlock_if_synchronized_offset() { return byte_offset_of(JavaThread, _do_not_unlock_if_synchronized); }
1673 static ByteSize should_post_on_exceptions_flag_offset() {
1674 return byte_offset_of(JavaThread, _should_post_on_exceptions_flag);
1675 }
1676
1677 #if INCLUDE_ALL_GCS
1678 static ByteSize satb_mark_queue_offset() { return byte_offset_of(JavaThread, _satb_mark_queue); }
1679 static ByteSize dirty_card_queue_offset() { return byte_offset_of(JavaThread, _dirty_card_queue); }
1680 #endif // INCLUDE_ALL_GCS
1681
1682 // Returns the jni environment for this thread
1683 JNIEnv* jni_environment() { return &_jni_environment; }
1684
1685 static JavaThread* thread_from_jni_environment(JNIEnv* env) {
1686 JavaThread *thread_from_jni_env = (JavaThread*)((intptr_t)env - in_bytes(jni_environment_offset()));
1687 // Only return NULL if thread is off the thread list; starting to
1688 // exit should not return NULL.
1689 if (thread_from_jni_env->is_terminated()) {
1690 thread_from_jni_env->block_if_vm_exited();
1691 return NULL;
1692 } else {
1693 return thread_from_jni_env;
1694 }
1695 }
1696
1697 // JNI critical regions. These can nest.
1698 bool in_critical() { return _jni_active_critical > 0; }
1699 bool in_last_critical() { return _jni_active_critical == 1; }
1700 void enter_critical() {
1701 assert(Thread::current() == this ||
1702 (Thread::current()->is_VM_thread() &&
1703 SafepointSynchronize::is_synchronizing()),
1704 "this must be current thread or synchronizing");
1705 _jni_active_critical++;
1706 }
1707 void exit_critical() {
1708 assert(Thread::current() == this, "this must be current thread");
1709 _jni_active_critical--;
1710 assert(_jni_active_critical >= 0, "JNI critical nesting problem?");
1711 }
1712
1713 // Checked JNI: is the programmer required to check for exceptions, if so specify
1714 // which function name. Returning to a Java frame should implicitly clear the
1715 // pending check, this is done for Native->Java transitions (i.e. user JNI code).
1716 // VM->Java transistions are not cleared, it is expected that JNI code enclosed
1717 // within ThreadToNativeFromVM makes proper exception checks (i.e. VM internal).
1718 bool is_pending_jni_exception_check() const { return _pending_jni_exception_check_fn != NULL; }
1719 void clear_pending_jni_exception_check() { _pending_jni_exception_check_fn = NULL; }
1720 const char* get_pending_jni_exception_check() const { return _pending_jni_exception_check_fn; }
1721 void set_pending_jni_exception_check(const char* fn_name) { _pending_jni_exception_check_fn = (char*) fn_name; }
1722
1723 // For deadlock detection
1724 int depth_first_number() { return _depth_first_number; }
1725 void set_depth_first_number(int dfn) { _depth_first_number = dfn; }
1726
1727 private:
1728 void set_monitor_chunks(MonitorChunk* monitor_chunks) { _monitor_chunks = monitor_chunks; }
1729
1730 public:
1731 MonitorChunk* monitor_chunks() const { return _monitor_chunks; }
1732 void add_monitor_chunk(MonitorChunk* chunk);
1733 void remove_monitor_chunk(MonitorChunk* chunk);
1734 bool in_deopt_handler() const { return _in_deopt_handler > 0; }
1735 void inc_in_deopt_handler() { _in_deopt_handler++; }
1736 void dec_in_deopt_handler() {
1737 assert(_in_deopt_handler > 0, "mismatched deopt nesting");
1738 if (_in_deopt_handler > 0) { // robustness
1739 _in_deopt_handler--;
1740 }
1741 }
1742
1743 private:
1744 void set_entry_point(ThreadFunction entry_point) { _entry_point = entry_point; }
1745
1746 public:
1747
1748 // Frame iteration; calls the function f for all frames on the stack
1749 void frames_do(void f(frame*, const RegisterMap*));
1750
1751 // Memory operations
1752 void oops_do(OopClosure* f, CodeBlobClosure* cf);
1753
1754 // Sweeper operations
1755 virtual void nmethods_do(CodeBlobClosure* cf);
1756
1757 // RedefineClasses Support
1758 void metadata_do(void f(Metadata*));
1759
1760 // Misc. operations
1761 char* name() const { return (char*)get_thread_name(); }
1762 void print_on(outputStream* st) const;
1763 void print_value();
1764 void print_thread_state_on(outputStream*) const PRODUCT_RETURN;
1765 void print_thread_state() const PRODUCT_RETURN;
1766 void print_on_error(outputStream* st, char* buf, int buflen) const;
1767 void print_name_on_error(outputStream* st, char* buf, int buflen) const;
1768 void verify();
1769 const char* get_thread_name() const;
1770 private:
1771 // factor out low-level mechanics for use in both normal and error cases
1772 const char* get_thread_name_string(char* buf = NULL, int buflen = 0) const;
1773 public:
1774 const char* get_threadgroup_name() const;
1775 const char* get_parent_name() const;
1776
1777 // Accessing frames
1778 frame last_frame() {
1779 _anchor.make_walkable(this);
1780 return pd_last_frame();
1781 }
1782 javaVFrame* last_java_vframe(RegisterMap* reg_map);
1783
1784 // Returns method at 'depth' java or native frames down the stack
1785 // Used for security checks
1786 Klass* security_get_caller_class(int depth);
1787
1788 // Print stack trace in external format
1789 void print_stack_on(outputStream* st);
1790 void print_stack() { print_stack_on(tty); }
1791
1792 // Print stack traces in various internal formats
1793 void trace_stack() PRODUCT_RETURN;
1794 void trace_stack_from(vframe* start_vf) PRODUCT_RETURN;
1795 void trace_frames() PRODUCT_RETURN;
1796 void trace_oops() PRODUCT_RETURN;
1797
1798 // Print an annotated view of the stack frames
1799 void print_frame_layout(int depth = 0, bool validate_only = false) NOT_DEBUG_RETURN;
1800 void validate_frame_layout() {
1801 print_frame_layout(0, true);
1802 }
1803
1804 // Returns the number of stack frames on the stack
1805 int depth() const;
1806
1807 // Function for testing deoptimization
1808 void deoptimize();
1809 void make_zombies();
1810
1811 void deoptimized_wrt_marked_nmethods();
1812
1813 public:
1814 // Returns the running thread as a JavaThread
1815 static inline JavaThread* current();
1816
1817 // Returns the active Java thread. Do not use this if you know you are calling
1818 // from a JavaThread, as it's slower than JavaThread::current. If called from
1819 // the VMThread, it also returns the JavaThread that instigated the VMThread's
1820 // operation. You may not want that either.
1821 static JavaThread* active();
1822
1823 inline CompilerThread* as_CompilerThread();
1824
1825 public:
1826 virtual void run();
1827 void thread_main_inner();
1828
1829 private:
1830 // PRIVILEGED STACK
1831 PrivilegedElement* _privileged_stack_top;
1832 GrowableArray<oop>* _array_for_gc;
1833 public:
1834
1835 // Returns the privileged_stack information.
1836 PrivilegedElement* privileged_stack_top() const { return _privileged_stack_top; }
1837 void set_privileged_stack_top(PrivilegedElement *e) { _privileged_stack_top = e; }
1838 void register_array_for_gc(GrowableArray<oop>* array) { _array_for_gc = array; }
1839
1840 public:
1841 // Thread local information maintained by JVMTI.
1842 void set_jvmti_thread_state(JvmtiThreadState *value) { _jvmti_thread_state = value; }
1843 // A JvmtiThreadState is lazily allocated. This jvmti_thread_state()
1844 // getter is used to get this JavaThread's JvmtiThreadState if it has
1845 // one which means NULL can be returned. JvmtiThreadState::state_for()
1846 // is used to get the specified JavaThread's JvmtiThreadState if it has
1847 // one or it allocates a new JvmtiThreadState for the JavaThread and
1848 // returns it. JvmtiThreadState::state_for() will return NULL only if
1849 // the specified JavaThread is exiting.
1850 JvmtiThreadState *jvmti_thread_state() const { return _jvmti_thread_state; }
1851 static ByteSize jvmti_thread_state_offset() { return byte_offset_of(JavaThread, _jvmti_thread_state); }
1852 void set_jvmti_get_loaded_classes_closure(JvmtiGetLoadedClassesClosure* value) { _jvmti_get_loaded_classes_closure = value; }
1853 JvmtiGetLoadedClassesClosure* get_jvmti_get_loaded_classes_closure() const { return _jvmti_get_loaded_classes_closure; }
1854
1855 // JVMTI PopFrame support
1856 // Setting and clearing popframe_condition
1857 // All of these enumerated values are bits. popframe_pending
1858 // indicates that a PopFrame() has been requested and not yet been
1859 // completed. popframe_processing indicates that that PopFrame() is in
1860 // the process of being completed. popframe_force_deopt_reexecution_bit
1861 // indicates that special handling is required when returning to a
1862 // deoptimized caller.
1863 enum PopCondition {
1864 popframe_inactive = 0x00,
1865 popframe_pending_bit = 0x01,
1866 popframe_processing_bit = 0x02,
1867 popframe_force_deopt_reexecution_bit = 0x04
1868 };
1869 PopCondition popframe_condition() { return (PopCondition) _popframe_condition; }
1870 void set_popframe_condition(PopCondition c) { _popframe_condition = c; }
1871 void set_popframe_condition_bit(PopCondition c) { _popframe_condition |= c; }
1872 void clear_popframe_condition() { _popframe_condition = popframe_inactive; }
1873 static ByteSize popframe_condition_offset() { return byte_offset_of(JavaThread, _popframe_condition); }
1874 bool has_pending_popframe() { return (popframe_condition() & popframe_pending_bit) != 0; }
1875 bool popframe_forcing_deopt_reexecution() { return (popframe_condition() & popframe_force_deopt_reexecution_bit) != 0; }
1876 void clear_popframe_forcing_deopt_reexecution() { _popframe_condition &= ~popframe_force_deopt_reexecution_bit; }
1877 #ifdef CC_INTERP
1878 bool pop_frame_pending(void) { return ((_popframe_condition & popframe_pending_bit) != 0); }
1879 void clr_pop_frame_pending(void) { _popframe_condition = popframe_inactive; }
1880 bool pop_frame_in_process(void) { return ((_popframe_condition & popframe_processing_bit) != 0); }
1881 void set_pop_frame_in_process(void) { _popframe_condition |= popframe_processing_bit; }
1882 void clr_pop_frame_in_process(void) { _popframe_condition &= ~popframe_processing_bit; }
1883 #endif
1884
1885 int frames_to_pop_failed_realloc() const { return _frames_to_pop_failed_realloc; }
1886 void set_frames_to_pop_failed_realloc(int nb) { _frames_to_pop_failed_realloc = nb; }
1887 void dec_frames_to_pop_failed_realloc() { _frames_to_pop_failed_realloc--; }
1888
1889 private:
1890 // Saved incoming arguments to popped frame.
1891 // Used only when popped interpreted frame returns to deoptimized frame.
1892 void* _popframe_preserved_args;
1893 int _popframe_preserved_args_size;
1894
1895 public:
1896 void popframe_preserve_args(ByteSize size_in_bytes, void* start);
1897 void* popframe_preserved_args();
1898 ByteSize popframe_preserved_args_size();
1899 WordSize popframe_preserved_args_size_in_words();
1900 void popframe_free_preserved_args();
1901
1902
1903 private:
1904 JvmtiThreadState *_jvmti_thread_state;
1905 JvmtiGetLoadedClassesClosure* _jvmti_get_loaded_classes_closure;
1906
1907 // Used by the interpreter in fullspeed mode for frame pop, method
1908 // entry, method exit and single stepping support. This field is
1909 // only set to non-zero by the VM_EnterInterpOnlyMode VM operation.
1910 // It can be set to zero asynchronously (i.e., without a VM operation
1911 // or a lock) so we have to be very careful.
1912 int _interp_only_mode;
1913
1914 public:
1915 // used by the interpreter for fullspeed debugging support (see above)
1916 static ByteSize interp_only_mode_offset() { return byte_offset_of(JavaThread, _interp_only_mode); }
1917 bool is_interp_only_mode() { return (_interp_only_mode != 0); }
1918 int get_interp_only_mode() { return _interp_only_mode; }
1919 void increment_interp_only_mode() { ++_interp_only_mode; }
1920 void decrement_interp_only_mode() { --_interp_only_mode; }
1921
1922 // support for cached flag that indicates whether exceptions need to be posted for this thread
1923 // if this is false, we can avoid deoptimizing when events are thrown
1924 // this gets set to reflect whether jvmtiExport::post_exception_throw would actually do anything
1925 private:
1926 int _should_post_on_exceptions_flag;
1927
1928 public:
1929 int should_post_on_exceptions_flag() { return _should_post_on_exceptions_flag; }
1930 void set_should_post_on_exceptions_flag(int val) { _should_post_on_exceptions_flag = val; }
1931
1932 private:
1933 ThreadStatistics *_thread_stat;
1934
1935 public:
1936 ThreadStatistics* get_thread_stat() const { return _thread_stat; }
1937
1938 // Return a blocker object for which this thread is blocked parking.
1939 oop current_park_blocker();
1940
1941 private:
1942 static size_t _stack_size_at_create;
1943
1944 public:
1945 static inline size_t stack_size_at_create(void) {
1946 return _stack_size_at_create;
1947 }
1948 static inline void set_stack_size_at_create(size_t value) {
1949 _stack_size_at_create = value;
1950 }
1951
1952 #if INCLUDE_ALL_GCS
1953 // SATB marking queue support
1954 SATBMarkQueue& satb_mark_queue() { return _satb_mark_queue; }
1955 static SATBMarkQueueSet& satb_mark_queue_set() {
1956 return _satb_mark_queue_set;
1957 }
1958
1959 // Dirty card queue support
1960 DirtyCardQueue& dirty_card_queue() { return _dirty_card_queue; }
1961 static DirtyCardQueueSet& dirty_card_queue_set() {
1962 return _dirty_card_queue_set;
1963 }
1964 #endif // INCLUDE_ALL_GCS
1965
1966 // Machine dependent stuff
1967 #include OS_CPU_HEADER(thread)
1968
1969 public:
1970 void set_blocked_on_compilation(bool value) {
1971 _blocked_on_compilation = value;
1972 }
1973
1974 bool blocked_on_compilation() {
1975 return _blocked_on_compilation;
1976 }
1977 protected:
1978 bool _blocked_on_compilation;
1979
1980
1981 // JSR166 per-thread parker
1982 private:
1983 Parker* _parker;
1984 public:
1985 Parker* parker() { return _parker; }
1986
1987 // Biased locking support
1988 private:
1989 GrowableArray<MonitorInfo*>* _cached_monitor_info;
1990 public:
1991 GrowableArray<MonitorInfo*>* cached_monitor_info() { return _cached_monitor_info; }
1992 void set_cached_monitor_info(GrowableArray<MonitorInfo*>* info) { _cached_monitor_info = info; }
1993
1994 // clearing/querying jni attach status
1995 bool is_attaching_via_jni() const { return _jni_attach_state == _attaching_via_jni; }
1996 bool has_attached_via_jni() const { return is_attaching_via_jni() || _jni_attach_state == _attached_via_jni; }
1997 inline void set_done_attaching_via_jni();
1998 };
1999
2000 // Inline implementation of JavaThread::current
2001 inline JavaThread* JavaThread::current() {
2002 Thread* thread = Thread::current();
2003 assert(thread->is_Java_thread(), "just checking");
2004 return (JavaThread*)thread;
2005 }
2006
2007 inline CompilerThread* JavaThread::as_CompilerThread() {
2008 assert(is_Compiler_thread(), "just checking");
2009 return (CompilerThread*)this;
2010 }
2011
2012 // Dedicated thread to sweep the code cache
2013 class CodeCacheSweeperThread : public JavaThread {
2014 CompiledMethod* _scanned_compiled_method; // nmethod being scanned by the sweeper
2015 public:
2016 CodeCacheSweeperThread();
2017 // Track the nmethod currently being scanned by the sweeper
2018 void set_scanned_compiled_method(CompiledMethod* cm) {
2019 assert(_scanned_compiled_method == NULL || cm == NULL, "should reset to NULL before writing a new value");
2020 _scanned_compiled_method = cm;
2021 }
2022
2023 // Hide sweeper thread from external view.
2024 bool is_hidden_from_external_view() const { return true; }
2025
2026 bool is_Code_cache_sweeper_thread() const { return true; }
2027
2028 // Prevent GC from unloading _scanned_compiled_method
2029 void oops_do(OopClosure* f, CodeBlobClosure* cf);
2030 void nmethods_do(CodeBlobClosure* cf);
2031 };
2032
2033 // A thread used for Compilation.
2034 class CompilerThread : public JavaThread {
2035 friend class VMStructs;
2036 private:
2037 CompilerCounters* _counters;
2038
2039 ciEnv* _env;
2040 CompileLog* _log;
2041 CompileTask* volatile _task; // print_threads_compiling can read this concurrently.
2042 CompileQueue* _queue;
2043 BufferBlob* _buffer_blob;
2044
2045 AbstractCompiler* _compiler;
2046
2047 public:
2048
2049 static CompilerThread* current();
2050
2051 CompilerThread(CompileQueue* queue, CompilerCounters* counters);
2052
2053 bool is_Compiler_thread() const { return true; }
2054
2055 virtual bool can_call_java() const;
2056
2057 // Hide native compiler threads from external view.
2058 bool is_hidden_from_external_view() const { return !can_call_java(); }
2059
2060 void set_compiler(AbstractCompiler* c) { _compiler = c; }
2061 AbstractCompiler* compiler() const { return _compiler; }
2062
2063 CompileQueue* queue() const { return _queue; }
2064 CompilerCounters* counters() const { return _counters; }
2065
2066 // Get/set the thread's compilation environment.
2067 ciEnv* env() { return _env; }
2068 void set_env(ciEnv* env) { _env = env; }
2069
2070 BufferBlob* get_buffer_blob() const { return _buffer_blob; }
2071 void set_buffer_blob(BufferBlob* b) { _buffer_blob = b; }
2072
2073 // Get/set the thread's logging information
2074 CompileLog* log() { return _log; }
2075 void init_log(CompileLog* log) {
2076 // Set once, for good.
2077 assert(_log == NULL, "set only once");
2078 _log = log;
2079 }
2080
2081 #ifndef PRODUCT
2082 private:
2083 IdealGraphPrinter *_ideal_graph_printer;
2084 public:
2085 IdealGraphPrinter *ideal_graph_printer() { return _ideal_graph_printer; }
2086 void set_ideal_graph_printer(IdealGraphPrinter *n) { _ideal_graph_printer = n; }
2087 #endif
2088
2089 // Get/set the thread's current task
2090 CompileTask* task() { return _task; }
2091 void set_task(CompileTask* task) { _task = task; }
2092 };
2093
2094 inline CompilerThread* CompilerThread::current() {
2095 return JavaThread::current()->as_CompilerThread();
2096 }
2097
2098 // The active thread queue. It also keeps track of the current used
2099 // thread priorities.
2100 class Threads: AllStatic {
2101 friend class VMStructs;
2102 private:
2103 static JavaThread* _thread_list;
2104 static int _number_of_threads;
2105 static int _number_of_non_daemon_threads;
2106 static int _return_code;
2107 static int _thread_claim_parity;
2108 #ifdef ASSERT
2109 static bool _vm_complete;
2110 #endif
2111
2112 static void initialize_java_lang_classes(JavaThread* main_thread, TRAPS);
2113 static void initialize_jsr292_core_classes(TRAPS);
2114
2115 public:
2116 // Thread management
2117 // force_daemon is a concession to JNI, where we may need to add a
2118 // thread to the thread list before allocating its thread object
2119 static void add(JavaThread* p, bool force_daemon = false);
2120 static void remove(JavaThread* p);
2121 static void threads_do(ThreadClosure* tc);
2122 static void possibly_parallel_threads_do(bool is_par, ThreadClosure* tc);
2123
2124 // Initializes the vm and creates the vm thread
2125 static jint create_vm(JavaVMInitArgs* args, bool* canTryAgain);
2126 static void convert_vm_init_libraries_to_agents();
2127 static void create_vm_init_libraries();
2128 static void create_vm_init_agents();
2129 static void shutdown_vm_agents();
2130 static bool destroy_vm();
2131 // Supported VM versions via JNI
2132 // Includes JNI_VERSION_1_1
2133 static jboolean is_supported_jni_version_including_1_1(jint version);
2134 // Does not include JNI_VERSION_1_1
2135 static jboolean is_supported_jni_version(jint version);
2136
2137 // The "thread claim parity" provides a way for threads to be claimed
2138 // by parallel worker tasks.
2139 //
2140 // Each thread contains a a "parity" field. A task will claim the
2141 // thread only if its parity field is the same as the global parity,
2142 // which is updated by calling change_thread_claim_parity().
2143 //
2144 // For this to work change_thread_claim_parity() needs to be called
2145 // exactly once in sequential code before starting parallel tasks
2146 // that should claim threads.
2147 //
2148 // New threads get their parity set to 0 and change_thread_claim_parity()
2149 // never set the global parity to 0.
2150 static int thread_claim_parity() { return _thread_claim_parity; }
2151 static void change_thread_claim_parity();
2152 static void assert_all_threads_claimed() NOT_DEBUG_RETURN;
2153
2154 // Apply "f->do_oop" to all root oops in all threads.
2155 // This version may only be called by sequential code.
2156 static void oops_do(OopClosure* f, CodeBlobClosure* cf);
2157 // This version may be called by sequential or parallel code.
2158 static void possibly_parallel_oops_do(bool is_par, OopClosure* f, CodeBlobClosure* cf);
2159 // This creates a list of GCTasks, one per thread.
2160 static void create_thread_roots_tasks(GCTaskQueue* q);
2161 // This creates a list of GCTasks, one per thread, for marking objects.
2162 static void create_thread_roots_marking_tasks(GCTaskQueue* q);
2163
2164 // Apply "f->do_oop" to roots in all threads that
2165 // are part of compiled frames
2166 static void compiled_frame_oops_do(OopClosure* f, CodeBlobClosure* cf);
2167
2168 static void convert_hcode_pointers();
2169 static void restore_hcode_pointers();
2170
2171 // Sweeper
2172 static void nmethods_do(CodeBlobClosure* cf);
2173
2174 // RedefineClasses support
2175 static void metadata_do(void f(Metadata*));
2176 static void metadata_handles_do(void f(Metadata*));
2177
2178 #ifdef ASSERT
2179 static bool is_vm_complete() { return _vm_complete; }
2180 #endif
2181
2182 // Verification
2183 static void verify();
2184 static void print_on(outputStream* st, bool print_stacks, bool internal_format, bool print_concurrent_locks);
2185 static void print(bool print_stacks, bool internal_format) {
2186 // this function is only used by debug.cpp
2187 print_on(tty, print_stacks, internal_format, false /* no concurrent lock printed */);
2188 }
2189 static void print_on_error(outputStream* st, Thread* current, char* buf, int buflen);
2190 static void print_on_error(Thread* this_thread, outputStream* st, Thread* current, char* buf,
2191 int buflen, bool* found_current);
2192 static void print_threads_compiling(outputStream* st, char* buf, int buflen);
2193
2194 // Get Java threads that are waiting to enter a monitor.
2195 static GrowableArray<JavaThread*>* get_pending_threads(ThreadsList * t_list,
2196 int count, address monitor);
2197
2198 // Get owning Java thread from the monitor's owner field.
2199 static JavaThread *owning_thread_from_monitor_owner(ThreadsList * t_list,
2200 address owner);
2201
2202 // Number of threads on the active threads list
2203 static int number_of_threads() { return _number_of_threads; }
2204 // Number of non-daemon threads on the active threads list
2205 static int number_of_non_daemon_threads() { return _number_of_non_daemon_threads; }
2206
2207 // Deoptimizes all frames tied to marked nmethods
2208 static void deoptimized_wrt_marked_nmethods();
2209 };
2210
2211
2212 // Thread iterator
2213 class ThreadClosure: public StackObj {
2214 public:
2215 virtual void do_thread(Thread* thread) = 0;
2216 };
2217
2218 class SignalHandlerMark: public StackObj {
2219 private:
2220 Thread* _thread;
2221 public:
2222 SignalHandlerMark(Thread* t) {
2223 _thread = t;
2224 if (_thread) _thread->enter_signal_handler();
2225 }
2226 ~SignalHandlerMark() {
2227 if (_thread) _thread->leave_signal_handler();
2228 _thread = NULL;
2229 }
2230 };
2231
2232
2233 #endif // SHARE_VM_RUNTIME_THREAD_HPP