Sat, 10 Sep 2011 00:11:04 -0700
7088020: SEGV in JNIHandleBlock::release_block
Reviewed-by: kvn, twisti
1 /*
2 * Copyright (c) 1997, 2011, 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 */
25 #ifndef SHARE_VM_RUNTIME_THREAD_HPP
26 #define SHARE_VM_RUNTIME_THREAD_HPP
28 #include "memory/allocation.hpp"
29 #include "memory/threadLocalAllocBuffer.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/unhandledOops.hpp"
44 #include "utilities/exceptions.hpp"
45 #include "utilities/top.hpp"
46 #ifndef SERIALGC
47 #include "gc_implementation/g1/dirtyCardQueue.hpp"
48 #include "gc_implementation/g1/satbQueue.hpp"
49 #endif
50 #ifdef ZERO
51 #ifdef TARGET_ARCH_zero
52 # include "stack_zero.hpp"
53 #endif
54 #endif
56 class ThreadSafepointState;
57 class ThreadProfiler;
59 class JvmtiThreadState;
60 class JvmtiGetLoadedClassesClosure;
61 class ThreadStatistics;
62 class ConcurrentLocksDump;
63 class ParkEvent;
64 class Parker;
66 class ciEnv;
67 class CompileThread;
68 class CompileLog;
69 class CompileTask;
70 class CompileQueue;
71 class CompilerCounters;
72 class vframeArray;
74 class DeoptResourceMark;
75 class jvmtiDeferredLocalVariableSet;
77 class GCTaskQueue;
78 class ThreadClosure;
79 class IdealGraphPrinter;
81 class WorkerThread;
83 // Class hierarchy
84 // - Thread
85 // - NamedThread
86 // - VMThread
87 // - ConcurrentGCThread
88 // - WorkerThread
89 // - GangWorker
90 // - GCTaskThread
91 // - JavaThread
92 // - WatcherThread
94 class Thread: public ThreadShadow {
95 friend class VMStructs;
96 private:
97 // Exception handling
98 // (Note: _pending_exception and friends are in ThreadShadow)
99 //oop _pending_exception; // pending exception for current thread
100 // const char* _exception_file; // file information for exception (debugging only)
101 // int _exception_line; // line information for exception (debugging only)
103 // Support for forcing alignment of thread objects for biased locking
104 void* _real_malloc_address;
105 public:
106 void* operator new(size_t size);
107 void operator delete(void* p);
108 private:
110 // ***************************************************************
111 // Suspend and resume support
112 // ***************************************************************
113 //
114 // VM suspend/resume no longer exists - it was once used for various
115 // things including safepoints but was deprecated and finally removed
116 // in Java 7. Because VM suspension was considered "internal" Java-level
117 // suspension was considered "external", and this legacy naming scheme
118 // remains.
119 //
120 // External suspend/resume requests come from JVM_SuspendThread,
121 // JVM_ResumeThread, JVMTI SuspendThread, and finally JVMTI
122 // ResumeThread. External
123 // suspend requests cause _external_suspend to be set and external
124 // resume requests cause _external_suspend to be cleared.
125 // External suspend requests do not nest on top of other external
126 // suspend requests. The higher level APIs reject suspend requests
127 // for already suspended threads.
128 //
129 // The external_suspend
130 // flag is checked by has_special_runtime_exit_condition() and java thread
131 // will self-suspend when handle_special_runtime_exit_condition() is
132 // called. Most uses of the _thread_blocked state in JavaThreads are
133 // considered the same as being externally suspended; if the blocking
134 // condition lifts, the JavaThread will self-suspend. Other places
135 // where VM checks for external_suspend include:
136 // + mutex granting (do not enter monitors when thread is suspended)
137 // + state transitions from _thread_in_native
138 //
139 // In general, java_suspend() does not wait for an external suspend
140 // request to complete. When it returns, the only guarantee is that
141 // the _external_suspend field is true.
142 //
143 // wait_for_ext_suspend_completion() is used to wait for an external
144 // suspend request to complete. External suspend requests are usually
145 // followed by some other interface call that requires the thread to
146 // be quiescent, e.g., GetCallTrace(). By moving the "wait time" into
147 // the interface that requires quiescence, we give the JavaThread a
148 // chance to self-suspend before we need it to be quiescent. This
149 // improves overall suspend/query performance.
150 //
151 // _suspend_flags controls the behavior of java_ suspend/resume.
152 // It must be set under the protection of SR_lock. Read from the flag is
153 // OK without SR_lock as long as the value is only used as a hint.
154 // (e.g., check _external_suspend first without lock and then recheck
155 // inside SR_lock and finish the suspension)
156 //
157 // _suspend_flags is also overloaded for other "special conditions" so
158 // that a single check indicates whether any special action is needed
159 // eg. for async exceptions.
160 // -------------------------------------------------------------------
161 // Notes:
162 // 1. The suspend/resume logic no longer uses ThreadState in OSThread
163 // but we still update its value to keep other part of the system (mainly
164 // JVMTI) happy. ThreadState is legacy code (see notes in
165 // osThread.hpp).
166 //
167 // 2. It would be more natural if set_external_suspend() is private and
168 // part of java_suspend(), but that probably would affect the suspend/query
169 // performance. Need more investigation on this.
170 //
172 // suspend/resume lock: used for self-suspend
173 Monitor* _SR_lock;
175 protected:
176 enum SuspendFlags {
177 // NOTE: avoid using the sign-bit as cc generates different test code
178 // when the sign-bit is used, and sometimes incorrectly - see CR 6398077
180 _external_suspend = 0x20000000U, // thread is asked to self suspend
181 _ext_suspended = 0x40000000U, // thread has self-suspended
182 _deopt_suspend = 0x10000000U, // thread needs to self suspend for deopt
184 _has_async_exception = 0x00000001U // there is a pending async exception
185 };
187 // various suspension related flags - atomically updated
188 // overloaded for async exception checking in check_special_condition_for_native_trans.
189 volatile uint32_t _suspend_flags;
191 private:
192 int _num_nested_signal;
194 public:
195 void enter_signal_handler() { _num_nested_signal++; }
196 void leave_signal_handler() { _num_nested_signal--; }
197 bool is_inside_signal_handler() const { return _num_nested_signal > 0; }
199 private:
200 // Debug tracing
201 static void trace(const char* msg, const Thread* const thread) PRODUCT_RETURN;
203 // Active_handles points to a block of handles
204 JNIHandleBlock* _active_handles;
206 // One-element thread local free list
207 JNIHandleBlock* _free_handle_block;
209 // Point to the last handle mark
210 HandleMark* _last_handle_mark;
212 // The parity of the last strong_roots iteration in which this thread was
213 // claimed as a task.
214 jint _oops_do_parity;
216 public:
217 void set_last_handle_mark(HandleMark* mark) { _last_handle_mark = mark; }
218 HandleMark* last_handle_mark() const { return _last_handle_mark; }
219 private:
221 // debug support for checking if code does allow safepoints or not
222 // GC points in the VM can happen because of allocation, invoking a VM operation, or blocking on
223 // mutex, or blocking on an object synchronizer (Java locking).
224 // If !allow_safepoint(), then an assertion failure will happen in any of the above cases
225 // If !allow_allocation(), then an assertion failure will happen during allocation
226 // (Hence, !allow_safepoint() => !allow_allocation()).
227 //
228 // The two classes No_Safepoint_Verifier and No_Allocation_Verifier are used to set these counters.
229 //
230 NOT_PRODUCT(int _allow_safepoint_count;) // If 0, thread allow a safepoint to happen
231 debug_only (int _allow_allocation_count;) // If 0, the thread is allowed to allocate oops.
233 // Used by SkipGCALot class.
234 NOT_PRODUCT(bool _skip_gcalot;) // Should we elide gc-a-lot?
236 // Record when GC is locked out via the GC_locker mechanism
237 CHECK_UNHANDLED_OOPS_ONLY(int _gc_locked_out_count;)
239 friend class No_Alloc_Verifier;
240 friend class No_Safepoint_Verifier;
241 friend class Pause_No_Safepoint_Verifier;
242 friend class ThreadLocalStorage;
243 friend class GC_locker;
245 ThreadLocalAllocBuffer _tlab; // Thread-local eden
246 jlong _allocated_bytes; // Cumulative number of bytes allocated on
247 // the Java heap
249 int _vm_operation_started_count; // VM_Operation support
250 int _vm_operation_completed_count; // VM_Operation support
252 ObjectMonitor* _current_pending_monitor; // ObjectMonitor this thread
253 // is waiting to lock
254 bool _current_pending_monitor_is_from_java; // locking is from Java code
256 // ObjectMonitor on which this thread called Object.wait()
257 ObjectMonitor* _current_waiting_monitor;
259 // Private thread-local objectmonitor list - a simple cache organized as a SLL.
260 public:
261 ObjectMonitor* omFreeList;
262 int omFreeCount; // length of omFreeList
263 int omFreeProvision; // reload chunk size
264 ObjectMonitor* omInUseList; // SLL to track monitors in circulation
265 int omInUseCount; // length of omInUseList
267 public:
268 enum {
269 is_definitely_current_thread = true
270 };
272 // Constructor
273 Thread();
274 virtual ~Thread();
276 // initializtion
277 void initialize_thread_local_storage();
279 // thread entry point
280 virtual void run();
282 // Testers
283 virtual bool is_VM_thread() const { return false; }
284 virtual bool is_Java_thread() const { return false; }
285 virtual bool is_Compiler_thread() const { return false; }
286 virtual bool is_hidden_from_external_view() const { return false; }
287 virtual bool is_jvmti_agent_thread() const { return false; }
288 // True iff the thread can perform GC operations at a safepoint.
289 // Generally will be true only of VM thread and parallel GC WorkGang
290 // threads.
291 virtual bool is_GC_task_thread() const { return false; }
292 virtual bool is_Watcher_thread() const { return false; }
293 virtual bool is_ConcurrentGC_thread() const { return false; }
294 virtual bool is_Named_thread() const { return false; }
295 virtual bool is_Worker_thread() const { return false; }
297 // Casts
298 virtual WorkerThread* as_Worker_thread() const { return NULL; }
300 virtual char* name() const { return (char*)"Unknown thread"; }
302 // Returns the current thread
303 static inline Thread* current();
305 // Common thread operations
306 static void set_priority(Thread* thread, ThreadPriority priority);
307 static ThreadPriority get_priority(const Thread* const thread);
308 static void start(Thread* thread);
309 static void interrupt(Thread* thr);
310 static bool is_interrupted(Thread* thr, bool clear_interrupted);
312 ObjectMonitor** omInUseList_addr() { return (ObjectMonitor **)&omInUseList; }
313 Monitor* SR_lock() const { return _SR_lock; }
315 bool has_async_exception() const { return (_suspend_flags & _has_async_exception) != 0; }
317 void set_suspend_flag(SuspendFlags f) {
318 assert(sizeof(jint) == sizeof(_suspend_flags), "size mismatch");
319 uint32_t flags;
320 do {
321 flags = _suspend_flags;
322 }
323 while (Atomic::cmpxchg((jint)(flags | f),
324 (volatile jint*)&_suspend_flags,
325 (jint)flags) != (jint)flags);
326 }
327 void clear_suspend_flag(SuspendFlags f) {
328 assert(sizeof(jint) == sizeof(_suspend_flags), "size mismatch");
329 uint32_t flags;
330 do {
331 flags = _suspend_flags;
332 }
333 while (Atomic::cmpxchg((jint)(flags & ~f),
334 (volatile jint*)&_suspend_flags,
335 (jint)flags) != (jint)flags);
336 }
338 void set_has_async_exception() {
339 set_suspend_flag(_has_async_exception);
340 }
341 void clear_has_async_exception() {
342 clear_suspend_flag(_has_async_exception);
343 }
345 // Support for Unhandled Oop detection
346 #ifdef CHECK_UNHANDLED_OOPS
347 private:
348 UnhandledOops* _unhandled_oops;
349 public:
350 UnhandledOops* unhandled_oops() { return _unhandled_oops; }
351 // Mark oop safe for gc. It may be stack allocated but won't move.
352 void allow_unhandled_oop(oop *op) {
353 if (CheckUnhandledOops) unhandled_oops()->allow_unhandled_oop(op);
354 }
355 // Clear oops at safepoint so crashes point to unhandled oop violator
356 void clear_unhandled_oops() {
357 if (CheckUnhandledOops) unhandled_oops()->clear_unhandled_oops();
358 }
359 bool is_gc_locked_out() { return _gc_locked_out_count > 0; }
360 #endif // CHECK_UNHANDLED_OOPS
362 #ifndef PRODUCT
363 bool skip_gcalot() { return _skip_gcalot; }
364 void set_skip_gcalot(bool v) { _skip_gcalot = v; }
365 #endif
367 public:
368 // Installs a pending exception to be inserted later
369 static void send_async_exception(oop thread_oop, oop java_throwable);
371 // Resource area
372 ResourceArea* resource_area() const { return _resource_area; }
373 void set_resource_area(ResourceArea* area) { _resource_area = area; }
375 OSThread* osthread() const { return _osthread; }
376 void set_osthread(OSThread* thread) { _osthread = thread; }
378 // JNI handle support
379 JNIHandleBlock* active_handles() const { return _active_handles; }
380 void set_active_handles(JNIHandleBlock* block) { _active_handles = block; }
381 JNIHandleBlock* free_handle_block() const { return _free_handle_block; }
382 void set_free_handle_block(JNIHandleBlock* block) { _free_handle_block = block; }
384 // Internal handle support
385 HandleArea* handle_area() const { return _handle_area; }
386 void set_handle_area(HandleArea* area) { _handle_area = area; }
388 // Thread-Local Allocation Buffer (TLAB) support
389 ThreadLocalAllocBuffer& tlab() { return _tlab; }
390 void initialize_tlab() {
391 if (UseTLAB) {
392 tlab().initialize();
393 }
394 }
396 jlong allocated_bytes() { return _allocated_bytes; }
397 void set_allocated_bytes(jlong value) { _allocated_bytes = value; }
398 void incr_allocated_bytes(jlong size) { _allocated_bytes += size; }
399 jlong cooked_allocated_bytes() {
400 jlong allocated_bytes = OrderAccess::load_acquire(&_allocated_bytes);
401 if (UseTLAB) {
402 size_t used_bytes = tlab().used_bytes();
403 if ((ssize_t)used_bytes > 0) {
404 // More-or-less valid tlab. The load_acquire above should ensure
405 // that the result of the add is <= the instantaneous value
406 return allocated_bytes + used_bytes;
407 }
408 }
409 return allocated_bytes;
410 }
412 // VM operation support
413 int vm_operation_ticket() { return ++_vm_operation_started_count; }
414 int vm_operation_completed_count() { return _vm_operation_completed_count; }
415 void increment_vm_operation_completed_count() { _vm_operation_completed_count++; }
417 // For tracking the heavyweight monitor the thread is pending on.
418 ObjectMonitor* current_pending_monitor() {
419 return _current_pending_monitor;
420 }
421 void set_current_pending_monitor(ObjectMonitor* monitor) {
422 _current_pending_monitor = monitor;
423 }
424 void set_current_pending_monitor_is_from_java(bool from_java) {
425 _current_pending_monitor_is_from_java = from_java;
426 }
427 bool current_pending_monitor_is_from_java() {
428 return _current_pending_monitor_is_from_java;
429 }
431 // For tracking the ObjectMonitor on which this thread called Object.wait()
432 ObjectMonitor* current_waiting_monitor() {
433 return _current_waiting_monitor;
434 }
435 void set_current_waiting_monitor(ObjectMonitor* monitor) {
436 _current_waiting_monitor = monitor;
437 }
439 // GC support
440 // Apply "f->do_oop" to all root oops in "this".
441 // Apply "cf->do_code_blob" (if !NULL) to all code blobs active in frames
442 virtual void oops_do(OopClosure* f, CodeBlobClosure* cf);
444 // Handles the parallel case for the method below.
445 private:
446 bool claim_oops_do_par_case(int collection_parity);
447 public:
448 // Requires that "collection_parity" is that of the current strong roots
449 // iteration. If "is_par" is false, sets the parity of "this" to
450 // "collection_parity", and returns "true". If "is_par" is true,
451 // uses an atomic instruction to set the current threads parity to
452 // "collection_parity", if it is not already. Returns "true" iff the
453 // calling thread does the update, this indicates that the calling thread
454 // has claimed the thread's stack as a root groop in the current
455 // collection.
456 bool claim_oops_do(bool is_par, int collection_parity) {
457 if (!is_par) {
458 _oops_do_parity = collection_parity;
459 return true;
460 } else {
461 return claim_oops_do_par_case(collection_parity);
462 }
463 }
465 // Sweeper support
466 void nmethods_do(CodeBlobClosure* cf);
468 // Used by fast lock support
469 virtual bool is_lock_owned(address adr) const;
471 // Check if address is in the stack of the thread (not just for locks).
472 // Warning: the method can only be used on the running thread
473 bool is_in_stack(address adr) const;
475 // Sets this thread as starting thread. Returns failure if thread
476 // creation fails due to lack of memory, too many threads etc.
477 bool set_as_starting_thread();
479 protected:
480 // OS data associated with the thread
481 OSThread* _osthread; // Platform-specific thread information
483 // Thread local resource area for temporary allocation within the VM
484 ResourceArea* _resource_area;
486 // Thread local handle area for allocation of handles within the VM
487 HandleArea* _handle_area;
489 // Support for stack overflow handling, get_thread, etc.
490 address _stack_base;
491 size_t _stack_size;
492 uintptr_t _self_raw_id; // used by get_thread (mutable)
493 int _lgrp_id;
495 public:
496 // Stack overflow support
497 address stack_base() const { assert(_stack_base != NULL,"Sanity check"); return _stack_base; }
499 void set_stack_base(address base) { _stack_base = base; }
500 size_t stack_size() const { return _stack_size; }
501 void set_stack_size(size_t size) { _stack_size = size; }
502 void record_stack_base_and_size();
504 bool on_local_stack(address adr) const {
505 /* QQQ this has knowledge of direction, ought to be a stack method */
506 return (_stack_base >= adr && adr >= (_stack_base - _stack_size));
507 }
509 uintptr_t self_raw_id() { return _self_raw_id; }
510 void set_self_raw_id(uintptr_t value) { _self_raw_id = value; }
512 int lgrp_id() const { return _lgrp_id; }
513 void set_lgrp_id(int value) { _lgrp_id = value; }
515 // Printing
516 void print_on(outputStream* st) const;
517 void print() const { print_on(tty); }
518 virtual void print_on_error(outputStream* st, char* buf, int buflen) const;
520 // Debug-only code
522 #ifdef ASSERT
523 private:
524 // Deadlock detection support for Mutex locks. List of locks own by thread.
525 Monitor* _owned_locks;
526 // Mutex::set_owner_implementation is the only place where _owned_locks is modified,
527 // thus the friendship
528 friend class Mutex;
529 friend class Monitor;
531 public:
532 void print_owned_locks_on(outputStream* st) const;
533 void print_owned_locks() const { print_owned_locks_on(tty); }
534 Monitor* owned_locks() const { return _owned_locks; }
535 bool owns_locks() const { return owned_locks() != NULL; }
536 bool owns_locks_but_compiled_lock() const;
538 // Deadlock detection
539 bool allow_allocation() { return _allow_allocation_count == 0; }
540 #endif
542 void check_for_valid_safepoint_state(bool potential_vm_operation) PRODUCT_RETURN;
544 private:
545 volatile int _jvmti_env_iteration_count;
547 public:
548 void entering_jvmti_env_iteration() { ++_jvmti_env_iteration_count; }
549 void leaving_jvmti_env_iteration() { --_jvmti_env_iteration_count; }
550 bool is_inside_jvmti_env_iteration() { return _jvmti_env_iteration_count > 0; }
552 // Code generation
553 static ByteSize exception_file_offset() { return byte_offset_of(Thread, _exception_file ); }
554 static ByteSize exception_line_offset() { return byte_offset_of(Thread, _exception_line ); }
555 static ByteSize active_handles_offset() { return byte_offset_of(Thread, _active_handles ); }
557 static ByteSize stack_base_offset() { return byte_offset_of(Thread, _stack_base ); }
558 static ByteSize stack_size_offset() { return byte_offset_of(Thread, _stack_size ); }
560 #define TLAB_FIELD_OFFSET(name) \
561 static ByteSize tlab_##name##_offset() { return byte_offset_of(Thread, _tlab) + ThreadLocalAllocBuffer::name##_offset(); }
563 TLAB_FIELD_OFFSET(start)
564 TLAB_FIELD_OFFSET(end)
565 TLAB_FIELD_OFFSET(top)
566 TLAB_FIELD_OFFSET(pf_top)
567 TLAB_FIELD_OFFSET(size) // desired_size
568 TLAB_FIELD_OFFSET(refill_waste_limit)
569 TLAB_FIELD_OFFSET(number_of_refills)
570 TLAB_FIELD_OFFSET(fast_refill_waste)
571 TLAB_FIELD_OFFSET(slow_allocations)
573 #undef TLAB_FIELD_OFFSET
575 static ByteSize allocated_bytes_offset() { return byte_offset_of(Thread, _allocated_bytes ); }
577 public:
578 volatile intptr_t _Stalled ;
579 volatile int _TypeTag ;
580 ParkEvent * _ParkEvent ; // for synchronized()
581 ParkEvent * _SleepEvent ; // for Thread.sleep
582 ParkEvent * _MutexEvent ; // for native internal Mutex/Monitor
583 ParkEvent * _MuxEvent ; // for low-level muxAcquire-muxRelease
584 int NativeSyncRecursion ; // diagnostic
586 volatile int _OnTrap ; // Resume-at IP delta
587 jint _hashStateW ; // Marsaglia Shift-XOR thread-local RNG
588 jint _hashStateX ; // thread-specific hashCode generator state
589 jint _hashStateY ;
590 jint _hashStateZ ;
591 void * _schedctl ;
593 intptr_t _ScratchA, _ScratchB ; // Scratch locations for fast-path sync code
594 static ByteSize ScratchA_offset() { return byte_offset_of(Thread, _ScratchA ); }
595 static ByteSize ScratchB_offset() { return byte_offset_of(Thread, _ScratchB ); }
597 volatile jint rng [4] ; // RNG for spin loop
599 // Low-level leaf-lock primitives used to implement synchronization
600 // and native monitor-mutex infrastructure.
601 // Not for general synchronization use.
602 static void SpinAcquire (volatile int * Lock, const char * Name) ;
603 static void SpinRelease (volatile int * Lock) ;
604 static void muxAcquire (volatile intptr_t * Lock, const char * Name) ;
605 static void muxAcquireW (volatile intptr_t * Lock, ParkEvent * ev) ;
606 static void muxRelease (volatile intptr_t * Lock) ;
607 };
609 // Inline implementation of Thread::current()
610 // Thread::current is "hot" it's called > 128K times in the 1st 500 msecs of
611 // startup.
612 // ThreadLocalStorage::thread is warm -- it's called > 16K times in the same
613 // period. This is inlined in thread_<os_family>.inline.hpp.
615 inline Thread* Thread::current() {
616 #ifdef ASSERT
617 // This function is very high traffic. Define PARANOID to enable expensive
618 // asserts.
619 #ifdef PARANOID
620 // Signal handler should call ThreadLocalStorage::get_thread_slow()
621 Thread* t = ThreadLocalStorage::get_thread_slow();
622 assert(t != NULL && !t->is_inside_signal_handler(),
623 "Don't use Thread::current() inside signal handler");
624 #endif
625 #endif
626 Thread* thread = ThreadLocalStorage::thread();
627 assert(thread != NULL, "just checking");
628 return thread;
629 }
631 // Name support for threads. non-JavaThread subclasses with multiple
632 // uniquely named instances should derive from this.
633 class NamedThread: public Thread {
634 friend class VMStructs;
635 enum {
636 max_name_len = 64
637 };
638 private:
639 char* _name;
640 // log JavaThread being processed by oops_do
641 JavaThread* _processed_thread;
643 public:
644 NamedThread();
645 ~NamedThread();
646 // May only be called once per thread.
647 void set_name(const char* format, ...);
648 virtual bool is_Named_thread() const { return true; }
649 virtual char* name() const { return _name == NULL ? (char*)"Unknown Thread" : _name; }
650 JavaThread *processed_thread() { return _processed_thread; }
651 void set_processed_thread(JavaThread *thread) { _processed_thread = thread; }
652 };
654 // Worker threads are named and have an id of an assigned work.
655 class WorkerThread: public NamedThread {
656 private:
657 uint _id;
658 public:
659 WorkerThread() : _id(0) { }
660 virtual bool is_Worker_thread() const { return true; }
662 virtual WorkerThread* as_Worker_thread() const {
663 assert(is_Worker_thread(), "Dubious cast to WorkerThread*?");
664 return (WorkerThread*) this;
665 }
667 void set_id(uint work_id) { _id = work_id; }
668 uint id() const { return _id; }
669 };
671 // A single WatcherThread is used for simulating timer interrupts.
672 class WatcherThread: public Thread {
673 friend class VMStructs;
674 public:
675 virtual void run();
677 private:
678 static WatcherThread* _watcher_thread;
680 volatile static bool _should_terminate; // updated without holding lock
681 public:
682 enum SomeConstants {
683 delay_interval = 10 // interrupt delay in milliseconds
684 };
686 // Constructor
687 WatcherThread();
689 // Tester
690 bool is_Watcher_thread() const { return true; }
692 // Printing
693 char* name() const { return (char*)"VM Periodic Task Thread"; }
694 void print_on(outputStream* st) const;
695 void print() const { print_on(tty); }
697 // Returns the single instance of WatcherThread
698 static WatcherThread* watcher_thread() { return _watcher_thread; }
700 // Create and start the single instance of WatcherThread, or stop it on shutdown
701 static void start();
702 static void stop();
703 };
706 class CompilerThread;
708 typedef void (*ThreadFunction)(JavaThread*, TRAPS);
710 class JavaThread: public Thread {
711 friend class VMStructs;
712 private:
713 JavaThread* _next; // The next thread in the Threads list
714 oop _threadObj; // The Java level thread object
716 #ifdef ASSERT
717 private:
718 int _java_call_counter;
720 public:
721 int java_call_counter() { return _java_call_counter; }
722 void inc_java_call_counter() { _java_call_counter++; }
723 void dec_java_call_counter() {
724 assert(_java_call_counter > 0, "Invalid nesting of JavaCallWrapper");
725 _java_call_counter--;
726 }
727 private: // restore original namespace restriction
728 #endif // ifdef ASSERT
730 #ifndef PRODUCT
731 public:
732 enum {
733 jump_ring_buffer_size = 16
734 };
735 private: // restore original namespace restriction
736 #endif
738 JavaFrameAnchor _anchor; // Encapsulation of current java frame and it state
740 ThreadFunction _entry_point;
742 JNIEnv _jni_environment;
744 // Deopt support
745 DeoptResourceMark* _deopt_mark; // Holds special ResourceMark for deoptimization
747 intptr_t* _must_deopt_id; // id of frame that needs to be deopted once we
748 // transition out of native
749 nmethod* _deopt_nmethod; // nmethod that is currently being deoptimized
750 vframeArray* _vframe_array_head; // Holds the heap of the active vframeArrays
751 vframeArray* _vframe_array_last; // Holds last vFrameArray we popped
752 // Because deoptimization is lazy we must save jvmti requests to set locals
753 // in compiled frames until we deoptimize and we have an interpreter frame.
754 // This holds the pointer to array (yeah like there might be more than one) of
755 // description of compiled vframes that have locals that need to be updated.
756 GrowableArray<jvmtiDeferredLocalVariableSet*>* _deferred_locals_updates;
758 // Handshake value for fixing 6243940. We need a place for the i2c
759 // adapter to store the callee methodOop. This value is NEVER live
760 // across a gc point so it does NOT have to be gc'd
761 // The handshake is open ended since we can't be certain that it will
762 // be NULLed. This is because we rarely ever see the race and end up
763 // in handle_wrong_method which is the backend of the handshake. See
764 // code in i2c adapters and handle_wrong_method.
766 methodOop _callee_target;
768 // Oop results of VM runtime calls
769 oop _vm_result; // Used to pass back an oop result into Java code, GC-preserved
770 oop _vm_result_2; // Used to pass back an oop result into Java code, GC-preserved
772 // See ReduceInitialCardMarks: this holds the precise space interval of
773 // the most recent slow path allocation for which compiled code has
774 // elided card-marks for performance along the fast-path.
775 MemRegion _deferred_card_mark;
777 MonitorChunk* _monitor_chunks; // Contains the off stack monitors
778 // allocated during deoptimization
779 // and by JNI_MonitorEnter/Exit
781 // Async. requests support
782 enum AsyncRequests {
783 _no_async_condition = 0,
784 _async_exception,
785 _async_unsafe_access_error
786 };
787 AsyncRequests _special_runtime_exit_condition; // Enum indicating pending async. request
788 oop _pending_async_exception;
790 // Safepoint support
791 public: // Expose _thread_state for SafeFetchInt()
792 volatile JavaThreadState _thread_state;
793 private:
794 ThreadSafepointState *_safepoint_state; // Holds information about a thread during a safepoint
795 address _saved_exception_pc; // Saved pc of instruction where last implicit exception happened
797 // JavaThread termination support
798 enum TerminatedTypes {
799 _not_terminated = 0xDEAD - 2,
800 _thread_exiting, // JavaThread::exit() has been called for this thread
801 _thread_terminated, // JavaThread is removed from thread list
802 _vm_exited // JavaThread is still executing native code, but VM is terminated
803 // only VM_Exit can set _vm_exited
804 };
806 // In general a JavaThread's _terminated field transitions as follows:
807 //
808 // _not_terminated => _thread_exiting => _thread_terminated
809 //
810 // _vm_exited is a special value to cover the case of a JavaThread
811 // executing native code after the VM itself is terminated.
812 volatile TerminatedTypes _terminated;
813 // suspend/resume support
814 volatile bool _suspend_equivalent; // Suspend equivalent condition
815 jint _in_deopt_handler; // count of deoptimization
816 // handlers thread is in
817 volatile bool _doing_unsafe_access; // Thread may fault due to unsafe access
818 bool _do_not_unlock_if_synchronized; // Do not unlock the receiver of a synchronized method (since it was
819 // never locked) when throwing an exception. Used by interpreter only.
821 // Flag to mark a JNI thread in the process of attaching - See CR 6404306
822 // This flag is never set true other than at construction, and in that case
823 // is shortly thereafter set false
824 volatile bool _is_attaching;
826 public:
827 // State of the stack guard pages for this thread.
828 enum StackGuardState {
829 stack_guard_unused, // not needed
830 stack_guard_yellow_disabled,// disabled (temporarily) after stack overflow
831 stack_guard_enabled // enabled
832 };
834 private:
836 StackGuardState _stack_guard_state;
838 // Compiler exception handling (NOTE: The _exception_oop is *NOT* the same as _pending_exception. It is
839 // used to temp. parsing values into and out of the runtime system during exception handling for compiled
840 // code)
841 volatile oop _exception_oop; // Exception thrown in compiled code
842 volatile address _exception_pc; // PC where exception happened
843 volatile address _exception_handler_pc; // PC for handler of exception
844 volatile int _is_method_handle_return; // true (== 1) if the current exception PC is a MethodHandle call site.
846 // support for compilation
847 bool _is_compiling; // is true if a compilation is active inthis thread (one compilation per thread possible)
849 // support for JNI critical regions
850 jint _jni_active_critical; // count of entries into JNI critical region
852 // For deadlock detection.
853 int _depth_first_number;
855 // JVMTI PopFrame support
856 // This is set to popframe_pending to signal that top Java frame should be popped immediately
857 int _popframe_condition;
859 #ifndef PRODUCT
860 int _jmp_ring_index;
861 struct {
862 // We use intptr_t instead of address so debugger doesn't try and display strings
863 intptr_t _target;
864 intptr_t _instruction;
865 const char* _file;
866 int _line;
867 } _jmp_ring[ jump_ring_buffer_size ];
868 #endif /* PRODUCT */
870 #ifndef SERIALGC
871 // Support for G1 barriers
873 ObjPtrQueue _satb_mark_queue; // Thread-local log for SATB barrier.
874 // Set of all such queues.
875 static SATBMarkQueueSet _satb_mark_queue_set;
877 DirtyCardQueue _dirty_card_queue; // Thread-local log for dirty cards.
878 // Set of all such queues.
879 static DirtyCardQueueSet _dirty_card_queue_set;
881 void flush_barrier_queues();
882 #endif // !SERIALGC
884 friend class VMThread;
885 friend class ThreadWaitTransition;
886 friend class VM_Exit;
888 void initialize(); // Initialized the instance variables
890 public:
891 // Constructor
892 JavaThread(bool is_attaching = false); // for main thread and JNI attached threads
893 JavaThread(ThreadFunction entry_point, size_t stack_size = 0);
894 ~JavaThread();
896 #ifdef ASSERT
897 // verify this JavaThread hasn't be published in the Threads::list yet
898 void verify_not_published();
899 #endif
901 //JNI functiontable getter/setter for JVMTI jni function table interception API.
902 void set_jni_functions(struct JNINativeInterface_* functionTable) {
903 _jni_environment.functions = functionTable;
904 }
905 struct JNINativeInterface_* get_jni_functions() {
906 return (struct JNINativeInterface_ *)_jni_environment.functions;
907 }
909 // This function is called at thread creation to allow
910 // platform specific thread variables to be initialized.
911 void cache_global_variables();
913 // Executes Shutdown.shutdown()
914 void invoke_shutdown_hooks();
916 // Cleanup on thread exit
917 enum ExitType {
918 normal_exit,
919 jni_detach
920 };
921 void exit(bool destroy_vm, ExitType exit_type = normal_exit);
923 void cleanup_failed_attach_current_thread();
925 // Testers
926 virtual bool is_Java_thread() const { return true; }
928 // compilation
929 void set_is_compiling(bool f) { _is_compiling = f; }
930 bool is_compiling() const { return _is_compiling; }
932 // Thread chain operations
933 JavaThread* next() const { return _next; }
934 void set_next(JavaThread* p) { _next = p; }
936 // Thread oop. threadObj() can be NULL for initial JavaThread
937 // (or for threads attached via JNI)
938 oop threadObj() const { return _threadObj; }
939 void set_threadObj(oop p) { _threadObj = p; }
941 ThreadPriority java_priority() const; // Read from threadObj()
943 // Prepare thread and add to priority queue. If a priority is
944 // not specified, use the priority of the thread object. Threads_lock
945 // must be held while this function is called.
946 void prepare(jobject jni_thread, ThreadPriority prio=NoPriority);
948 void set_saved_exception_pc(address pc) { _saved_exception_pc = pc; }
949 address saved_exception_pc() { return _saved_exception_pc; }
952 ThreadFunction entry_point() const { return _entry_point; }
954 // Allocates a new Java level thread object for this thread. thread_name may be NULL.
955 void allocate_threadObj(Handle thread_group, char* thread_name, bool daemon, TRAPS);
957 // Last frame anchor routines
959 JavaFrameAnchor* frame_anchor(void) { return &_anchor; }
961 // last_Java_sp
962 bool has_last_Java_frame() const { return _anchor.has_last_Java_frame(); }
963 intptr_t* last_Java_sp() const { return _anchor.last_Java_sp(); }
965 // last_Java_pc
967 address last_Java_pc(void) { return _anchor.last_Java_pc(); }
969 // Safepoint support
970 JavaThreadState thread_state() const { return _thread_state; }
971 void set_thread_state(JavaThreadState s) { _thread_state=s; }
972 ThreadSafepointState *safepoint_state() const { return _safepoint_state; }
973 void set_safepoint_state(ThreadSafepointState *state) { _safepoint_state = state; }
974 bool is_at_poll_safepoint() { return _safepoint_state->is_at_poll_safepoint(); }
976 // thread has called JavaThread::exit() or is terminated
977 bool is_exiting() { return _terminated == _thread_exiting || is_terminated(); }
978 // thread is terminated (no longer on the threads list); we compare
979 // against the two non-terminated values so that a freed JavaThread
980 // will also be considered terminated.
981 bool is_terminated() { return _terminated != _not_terminated && _terminated != _thread_exiting; }
982 void set_terminated(TerminatedTypes t) { _terminated = t; }
983 // special for Threads::remove() which is static:
984 void set_terminated_value() { _terminated = _thread_terminated; }
985 void block_if_vm_exited();
987 bool doing_unsafe_access() { return _doing_unsafe_access; }
988 void set_doing_unsafe_access(bool val) { _doing_unsafe_access = val; }
990 bool do_not_unlock_if_synchronized() { return _do_not_unlock_if_synchronized; }
991 void set_do_not_unlock_if_synchronized(bool val) { _do_not_unlock_if_synchronized = val; }
994 // Suspend/resume support for JavaThread
996 private:
997 void set_ext_suspended() { set_suspend_flag (_ext_suspended); }
998 void clear_ext_suspended() { clear_suspend_flag(_ext_suspended); }
1000 public:
1001 void java_suspend();
1002 void java_resume();
1003 int java_suspend_self();
1005 void check_and_wait_while_suspended() {
1006 assert(JavaThread::current() == this, "sanity check");
1008 bool do_self_suspend;
1009 do {
1010 // were we externally suspended while we were waiting?
1011 do_self_suspend = handle_special_suspend_equivalent_condition();
1012 if (do_self_suspend) {
1013 // don't surprise the thread that suspended us by returning
1014 java_suspend_self();
1015 set_suspend_equivalent();
1016 }
1017 } while (do_self_suspend);
1018 }
1019 static void check_safepoint_and_suspend_for_native_trans(JavaThread *thread);
1020 // Check for async exception in addition to safepoint and suspend request.
1021 static void check_special_condition_for_native_trans(JavaThread *thread);
1023 bool is_ext_suspend_completed(bool called_by_wait, int delay, uint32_t *bits);
1024 bool is_ext_suspend_completed_with_lock(uint32_t *bits) {
1025 MutexLockerEx ml(SR_lock(), Mutex::_no_safepoint_check_flag);
1026 // Warning: is_ext_suspend_completed() may temporarily drop the
1027 // SR_lock to allow the thread to reach a stable thread state if
1028 // it is currently in a transient thread state.
1029 return is_ext_suspend_completed(false /*!called_by_wait */,
1030 SuspendRetryDelay, bits);
1031 }
1033 // We cannot allow wait_for_ext_suspend_completion() to run forever or
1034 // we could hang. SuspendRetryCount and SuspendRetryDelay are normally
1035 // passed as the count and delay parameters. Experiments with specific
1036 // calls to wait_for_ext_suspend_completion() can be done by passing
1037 // other values in the code. Experiments with all calls can be done
1038 // via the appropriate -XX options.
1039 bool wait_for_ext_suspend_completion(int count, int delay, uint32_t *bits);
1041 void set_external_suspend() { set_suspend_flag (_external_suspend); }
1042 void clear_external_suspend() { clear_suspend_flag(_external_suspend); }
1044 void set_deopt_suspend() { set_suspend_flag (_deopt_suspend); }
1045 void clear_deopt_suspend() { clear_suspend_flag(_deopt_suspend); }
1046 bool is_deopt_suspend() { return (_suspend_flags & _deopt_suspend) != 0; }
1048 bool is_external_suspend() const {
1049 return (_suspend_flags & _external_suspend) != 0;
1050 }
1051 // Whenever a thread transitions from native to vm/java it must suspend
1052 // if external|deopt suspend is present.
1053 bool is_suspend_after_native() const {
1054 return (_suspend_flags & (_external_suspend | _deopt_suspend) ) != 0;
1055 }
1057 // external suspend request is completed
1058 bool is_ext_suspended() const {
1059 return (_suspend_flags & _ext_suspended) != 0;
1060 }
1062 bool is_external_suspend_with_lock() const {
1063 MutexLockerEx ml(SR_lock(), Mutex::_no_safepoint_check_flag);
1064 return is_external_suspend();
1065 }
1067 // Special method to handle a pending external suspend request
1068 // when a suspend equivalent condition lifts.
1069 bool handle_special_suspend_equivalent_condition() {
1070 assert(is_suspend_equivalent(),
1071 "should only be called in a suspend equivalence condition");
1072 MutexLockerEx ml(SR_lock(), Mutex::_no_safepoint_check_flag);
1073 bool ret = is_external_suspend();
1074 if (!ret) {
1075 // not about to self-suspend so clear suspend equivalence
1076 clear_suspend_equivalent();
1077 }
1078 // implied else:
1079 // We have a pending external suspend request so we leave the
1080 // suspend_equivalent flag set until java_suspend_self() sets
1081 // the ext_suspended flag and clears the suspend_equivalent
1082 // flag. This insures that wait_for_ext_suspend_completion()
1083 // will return consistent values.
1084 return ret;
1085 }
1087 // utility methods to see if we are doing some kind of suspension
1088 bool is_being_ext_suspended() const {
1089 MutexLockerEx ml(SR_lock(), Mutex::_no_safepoint_check_flag);
1090 return is_ext_suspended() || is_external_suspend();
1091 }
1093 bool is_suspend_equivalent() const { return _suspend_equivalent; }
1095 void set_suspend_equivalent() { _suspend_equivalent = true; };
1096 void clear_suspend_equivalent() { _suspend_equivalent = false; };
1098 // Thread.stop support
1099 void send_thread_stop(oop throwable);
1100 AsyncRequests clear_special_runtime_exit_condition() {
1101 AsyncRequests x = _special_runtime_exit_condition;
1102 _special_runtime_exit_condition = _no_async_condition;
1103 return x;
1104 }
1106 // Are any async conditions present?
1107 bool has_async_condition() { return (_special_runtime_exit_condition != _no_async_condition); }
1109 void check_and_handle_async_exceptions(bool check_unsafe_error = true);
1111 // these next two are also used for self-suspension and async exception support
1112 void handle_special_runtime_exit_condition(bool check_asyncs = true);
1114 // Return true if JavaThread has an asynchronous condition or
1115 // if external suspension is requested.
1116 bool has_special_runtime_exit_condition() {
1117 // We call is_external_suspend() last since external suspend should
1118 // be less common. Because we don't use is_external_suspend_with_lock
1119 // it is possible that we won't see an asynchronous external suspend
1120 // request that has just gotten started, i.e., SR_lock grabbed but
1121 // _external_suspend field change either not made yet or not visible
1122 // yet. However, this is okay because the request is asynchronous and
1123 // we will see the new flag value the next time through. It's also
1124 // possible that the external suspend request is dropped after
1125 // we have checked is_external_suspend(), we will recheck its value
1126 // under SR_lock in java_suspend_self().
1127 return (_special_runtime_exit_condition != _no_async_condition) ||
1128 is_external_suspend() || is_deopt_suspend();
1129 }
1131 void set_pending_unsafe_access_error() { _special_runtime_exit_condition = _async_unsafe_access_error; }
1133 void set_pending_async_exception(oop e) {
1134 _pending_async_exception = e;
1135 _special_runtime_exit_condition = _async_exception;
1136 set_has_async_exception();
1137 }
1139 // Fast-locking support
1140 bool is_lock_owned(address adr) const;
1142 // Accessors for vframe array top
1143 // The linked list of vframe arrays are sorted on sp. This means when we
1144 // unpack the head must contain the vframe array to unpack.
1145 void set_vframe_array_head(vframeArray* value) { _vframe_array_head = value; }
1146 vframeArray* vframe_array_head() const { return _vframe_array_head; }
1148 // Side structure for defering update of java frame locals until deopt occurs
1149 GrowableArray<jvmtiDeferredLocalVariableSet*>* deferred_locals() const { return _deferred_locals_updates; }
1150 void set_deferred_locals(GrowableArray<jvmtiDeferredLocalVariableSet *>* vf) { _deferred_locals_updates = vf; }
1152 // These only really exist to make debugging deopt problems simpler
1154 void set_vframe_array_last(vframeArray* value) { _vframe_array_last = value; }
1155 vframeArray* vframe_array_last() const { return _vframe_array_last; }
1157 // The special resourceMark used during deoptimization
1159 void set_deopt_mark(DeoptResourceMark* value) { _deopt_mark = value; }
1160 DeoptResourceMark* deopt_mark(void) { return _deopt_mark; }
1162 intptr_t* must_deopt_id() { return _must_deopt_id; }
1163 void set_must_deopt_id(intptr_t* id) { _must_deopt_id = id; }
1164 void clear_must_deopt_id() { _must_deopt_id = NULL; }
1166 void set_deopt_nmethod(nmethod* nm) { _deopt_nmethod = nm; }
1167 nmethod* deopt_nmethod() { return _deopt_nmethod; }
1169 methodOop callee_target() const { return _callee_target; }
1170 void set_callee_target (methodOop x) { _callee_target = x; }
1172 // Oop results of vm runtime calls
1173 oop vm_result() const { return _vm_result; }
1174 void set_vm_result (oop x) { _vm_result = x; }
1176 oop vm_result_2() const { return _vm_result_2; }
1177 void set_vm_result_2 (oop x) { _vm_result_2 = x; }
1179 MemRegion deferred_card_mark() const { return _deferred_card_mark; }
1180 void set_deferred_card_mark(MemRegion mr) { _deferred_card_mark = mr; }
1182 // Exception handling for compiled methods
1183 oop exception_oop() const { return _exception_oop; }
1184 address exception_pc() const { return _exception_pc; }
1185 address exception_handler_pc() const { return _exception_handler_pc; }
1186 bool is_method_handle_return() const { return _is_method_handle_return == 1; }
1188 void set_exception_oop(oop o) { _exception_oop = o; }
1189 void set_exception_pc(address a) { _exception_pc = a; }
1190 void set_exception_handler_pc(address a) { _exception_handler_pc = a; }
1191 void set_is_method_handle_return(bool value) { _is_method_handle_return = value ? 1 : 0; }
1193 // Stack overflow support
1194 inline size_t stack_available(address cur_sp);
1195 address stack_yellow_zone_base()
1196 { return (address)(stack_base() - (stack_size() - (stack_red_zone_size() + stack_yellow_zone_size()))); }
1197 size_t stack_yellow_zone_size()
1198 { return StackYellowPages * os::vm_page_size(); }
1199 address stack_red_zone_base()
1200 { return (address)(stack_base() - (stack_size() - stack_red_zone_size())); }
1201 size_t stack_red_zone_size()
1202 { return StackRedPages * os::vm_page_size(); }
1203 bool in_stack_yellow_zone(address a)
1204 { return (a <= stack_yellow_zone_base()) && (a >= stack_red_zone_base()); }
1205 bool in_stack_red_zone(address a)
1206 { return (a <= stack_red_zone_base()) && (a >= (address)((intptr_t)stack_base() - stack_size())); }
1208 void create_stack_guard_pages();
1209 void remove_stack_guard_pages();
1211 void enable_stack_yellow_zone();
1212 void disable_stack_yellow_zone();
1213 void enable_stack_red_zone();
1214 void disable_stack_red_zone();
1216 inline bool stack_yellow_zone_disabled();
1217 inline bool stack_yellow_zone_enabled();
1219 // Attempt to reguard the stack after a stack overflow may have occurred.
1220 // Returns true if (a) guard pages are not needed on this thread, (b) the
1221 // pages are already guarded, or (c) the pages were successfully reguarded.
1222 // Returns false if there is not enough stack space to reguard the pages, in
1223 // which case the caller should unwind a frame and try again. The argument
1224 // should be the caller's (approximate) sp.
1225 bool reguard_stack(address cur_sp);
1226 // Similar to above but see if current stackpoint is out of the guard area
1227 // and reguard if possible.
1228 bool reguard_stack(void);
1230 // Misc. accessors/mutators
1231 void set_do_not_unlock(void) { _do_not_unlock_if_synchronized = true; }
1232 void clr_do_not_unlock(void) { _do_not_unlock_if_synchronized = false; }
1233 bool do_not_unlock(void) { return _do_not_unlock_if_synchronized; }
1235 #ifndef PRODUCT
1236 void record_jump(address target, address instr, const char* file, int line);
1237 #endif /* PRODUCT */
1239 // For assembly stub generation
1240 static ByteSize threadObj_offset() { return byte_offset_of(JavaThread, _threadObj ); }
1241 #ifndef PRODUCT
1242 static ByteSize jmp_ring_index_offset() { return byte_offset_of(JavaThread, _jmp_ring_index ); }
1243 static ByteSize jmp_ring_offset() { return byte_offset_of(JavaThread, _jmp_ring ); }
1244 #endif /* PRODUCT */
1245 static ByteSize jni_environment_offset() { return byte_offset_of(JavaThread, _jni_environment ); }
1246 static ByteSize last_Java_sp_offset() {
1247 return byte_offset_of(JavaThread, _anchor) + JavaFrameAnchor::last_Java_sp_offset();
1248 }
1249 static ByteSize last_Java_pc_offset() {
1250 return byte_offset_of(JavaThread, _anchor) + JavaFrameAnchor::last_Java_pc_offset();
1251 }
1252 static ByteSize frame_anchor_offset() {
1253 return byte_offset_of(JavaThread, _anchor);
1254 }
1255 static ByteSize callee_target_offset() { return byte_offset_of(JavaThread, _callee_target ); }
1256 static ByteSize vm_result_offset() { return byte_offset_of(JavaThread, _vm_result ); }
1257 static ByteSize vm_result_2_offset() { return byte_offset_of(JavaThread, _vm_result_2 ); }
1258 static ByteSize thread_state_offset() { return byte_offset_of(JavaThread, _thread_state ); }
1259 static ByteSize saved_exception_pc_offset() { return byte_offset_of(JavaThread, _saved_exception_pc ); }
1260 static ByteSize osthread_offset() { return byte_offset_of(JavaThread, _osthread ); }
1261 static ByteSize exception_oop_offset() { return byte_offset_of(JavaThread, _exception_oop ); }
1262 static ByteSize exception_pc_offset() { return byte_offset_of(JavaThread, _exception_pc ); }
1263 static ByteSize exception_handler_pc_offset() { return byte_offset_of(JavaThread, _exception_handler_pc); }
1264 static ByteSize is_method_handle_return_offset() { return byte_offset_of(JavaThread, _is_method_handle_return); }
1265 static ByteSize stack_guard_state_offset() { return byte_offset_of(JavaThread, _stack_guard_state ); }
1266 static ByteSize suspend_flags_offset() { return byte_offset_of(JavaThread, _suspend_flags ); }
1268 static ByteSize do_not_unlock_if_synchronized_offset() { return byte_offset_of(JavaThread, _do_not_unlock_if_synchronized); }
1269 static ByteSize should_post_on_exceptions_flag_offset() {
1270 return byte_offset_of(JavaThread, _should_post_on_exceptions_flag);
1271 }
1273 #ifndef SERIALGC
1274 static ByteSize satb_mark_queue_offset() { return byte_offset_of(JavaThread, _satb_mark_queue); }
1275 static ByteSize dirty_card_queue_offset() { return byte_offset_of(JavaThread, _dirty_card_queue); }
1276 #endif // !SERIALGC
1278 // Returns the jni environment for this thread
1279 JNIEnv* jni_environment() { return &_jni_environment; }
1281 static JavaThread* thread_from_jni_environment(JNIEnv* env) {
1282 JavaThread *thread_from_jni_env = (JavaThread*)((intptr_t)env - in_bytes(jni_environment_offset()));
1283 // Only return NULL if thread is off the thread list; starting to
1284 // exit should not return NULL.
1285 if (thread_from_jni_env->is_terminated()) {
1286 thread_from_jni_env->block_if_vm_exited();
1287 return NULL;
1288 } else {
1289 return thread_from_jni_env;
1290 }
1291 }
1293 // JNI critical regions. These can nest.
1294 bool in_critical() { return _jni_active_critical > 0; }
1295 void enter_critical() { assert(Thread::current() == this,
1296 "this must be current thread");
1297 _jni_active_critical++; }
1298 void exit_critical() { assert(Thread::current() == this,
1299 "this must be current thread");
1300 _jni_active_critical--;
1301 assert(_jni_active_critical >= 0,
1302 "JNI critical nesting problem?"); }
1304 // For deadlock detection
1305 int depth_first_number() { return _depth_first_number; }
1306 void set_depth_first_number(int dfn) { _depth_first_number = dfn; }
1308 private:
1309 void set_monitor_chunks(MonitorChunk* monitor_chunks) { _monitor_chunks = monitor_chunks; }
1311 public:
1312 MonitorChunk* monitor_chunks() const { return _monitor_chunks; }
1313 void add_monitor_chunk(MonitorChunk* chunk);
1314 void remove_monitor_chunk(MonitorChunk* chunk);
1315 bool in_deopt_handler() const { return _in_deopt_handler > 0; }
1316 void inc_in_deopt_handler() { _in_deopt_handler++; }
1317 void dec_in_deopt_handler() {
1318 assert(_in_deopt_handler > 0, "mismatched deopt nesting");
1319 if (_in_deopt_handler > 0) { // robustness
1320 _in_deopt_handler--;
1321 }
1322 }
1324 private:
1325 void set_entry_point(ThreadFunction entry_point) { _entry_point = entry_point; }
1327 public:
1329 // Frame iteration; calls the function f for all frames on the stack
1330 void frames_do(void f(frame*, const RegisterMap*));
1332 // Memory operations
1333 void oops_do(OopClosure* f, CodeBlobClosure* cf);
1335 // Sweeper operations
1336 void nmethods_do(CodeBlobClosure* cf);
1338 // Memory management operations
1339 void gc_epilogue();
1340 void gc_prologue();
1342 // Misc. operations
1343 char* name() const { return (char*)get_thread_name(); }
1344 void print_on(outputStream* st) const;
1345 void print() const { print_on(tty); }
1346 void print_value();
1347 void print_thread_state_on(outputStream* ) const PRODUCT_RETURN;
1348 void print_thread_state() const PRODUCT_RETURN;
1349 void print_on_error(outputStream* st, char* buf, int buflen) const;
1350 void verify();
1351 const char* get_thread_name() const;
1352 private:
1353 // factor out low-level mechanics for use in both normal and error cases
1354 const char* get_thread_name_string(char* buf = NULL, int buflen = 0) const;
1355 public:
1356 const char* get_threadgroup_name() const;
1357 const char* get_parent_name() const;
1359 // Accessing frames
1360 frame last_frame() {
1361 _anchor.make_walkable(this);
1362 return pd_last_frame();
1363 }
1364 javaVFrame* last_java_vframe(RegisterMap* reg_map);
1366 // Returns method at 'depth' java or native frames down the stack
1367 // Used for security checks
1368 klassOop security_get_caller_class(int depth);
1370 // Print stack trace in external format
1371 void print_stack_on(outputStream* st);
1372 void print_stack() { print_stack_on(tty); }
1374 // Print stack traces in various internal formats
1375 void trace_stack() PRODUCT_RETURN;
1376 void trace_stack_from(vframe* start_vf) PRODUCT_RETURN;
1377 void trace_frames() PRODUCT_RETURN;
1378 void trace_oops() PRODUCT_RETURN;
1380 // Print an annotated view of the stack frames
1381 void print_frame_layout(int depth = 0, bool validate_only = false) NOT_DEBUG_RETURN;
1382 void validate_frame_layout() {
1383 print_frame_layout(0, true);
1384 }
1386 // Returns the number of stack frames on the stack
1387 int depth() const;
1389 // Function for testing deoptimization
1390 void deoptimize();
1391 void make_zombies();
1393 void deoptimized_wrt_marked_nmethods();
1395 // Profiling operation (see fprofile.cpp)
1396 public:
1397 bool profile_last_Java_frame(frame* fr);
1399 private:
1400 ThreadProfiler* _thread_profiler;
1401 private:
1402 friend class FlatProfiler; // uses both [gs]et_thread_profiler.
1403 friend class FlatProfilerTask; // uses get_thread_profiler.
1404 friend class ThreadProfilerMark; // uses get_thread_profiler.
1405 ThreadProfiler* get_thread_profiler() { return _thread_profiler; }
1406 ThreadProfiler* set_thread_profiler(ThreadProfiler* tp) {
1407 ThreadProfiler* result = _thread_profiler;
1408 _thread_profiler = tp;
1409 return result;
1410 }
1412 // Static operations
1413 public:
1414 // Returns the running thread as a JavaThread
1415 static inline JavaThread* current();
1417 // Returns the active Java thread. Do not use this if you know you are calling
1418 // from a JavaThread, as it's slower than JavaThread::current. If called from
1419 // the VMThread, it also returns the JavaThread that instigated the VMThread's
1420 // operation. You may not want that either.
1421 static JavaThread* active();
1423 inline CompilerThread* as_CompilerThread();
1425 public:
1426 virtual void run();
1427 void thread_main_inner();
1429 private:
1430 // PRIVILEGED STACK
1431 PrivilegedElement* _privileged_stack_top;
1432 GrowableArray<oop>* _array_for_gc;
1433 public:
1435 // Returns the privileged_stack information.
1436 PrivilegedElement* privileged_stack_top() const { return _privileged_stack_top; }
1437 void set_privileged_stack_top(PrivilegedElement *e) { _privileged_stack_top = e; }
1438 void register_array_for_gc(GrowableArray<oop>* array) { _array_for_gc = array; }
1440 public:
1441 // Thread local information maintained by JVMTI.
1442 void set_jvmti_thread_state(JvmtiThreadState *value) { _jvmti_thread_state = value; }
1443 // A JvmtiThreadState is lazily allocated. This jvmti_thread_state()
1444 // getter is used to get this JavaThread's JvmtiThreadState if it has
1445 // one which means NULL can be returned. JvmtiThreadState::state_for()
1446 // is used to get the specified JavaThread's JvmtiThreadState if it has
1447 // one or it allocates a new JvmtiThreadState for the JavaThread and
1448 // returns it. JvmtiThreadState::state_for() will return NULL only if
1449 // the specified JavaThread is exiting.
1450 JvmtiThreadState *jvmti_thread_state() const { return _jvmti_thread_state; }
1451 static ByteSize jvmti_thread_state_offset() { return byte_offset_of(JavaThread, _jvmti_thread_state); }
1452 void set_jvmti_get_loaded_classes_closure(JvmtiGetLoadedClassesClosure* value) { _jvmti_get_loaded_classes_closure = value; }
1453 JvmtiGetLoadedClassesClosure* get_jvmti_get_loaded_classes_closure() const { return _jvmti_get_loaded_classes_closure; }
1455 // JVMTI PopFrame support
1456 // Setting and clearing popframe_condition
1457 // All of these enumerated values are bits. popframe_pending
1458 // indicates that a PopFrame() has been requested and not yet been
1459 // completed. popframe_processing indicates that that PopFrame() is in
1460 // the process of being completed. popframe_force_deopt_reexecution_bit
1461 // indicates that special handling is required when returning to a
1462 // deoptimized caller.
1463 enum PopCondition {
1464 popframe_inactive = 0x00,
1465 popframe_pending_bit = 0x01,
1466 popframe_processing_bit = 0x02,
1467 popframe_force_deopt_reexecution_bit = 0x04
1468 };
1469 PopCondition popframe_condition() { return (PopCondition) _popframe_condition; }
1470 void set_popframe_condition(PopCondition c) { _popframe_condition = c; }
1471 void set_popframe_condition_bit(PopCondition c) { _popframe_condition |= c; }
1472 void clear_popframe_condition() { _popframe_condition = popframe_inactive; }
1473 static ByteSize popframe_condition_offset() { return byte_offset_of(JavaThread, _popframe_condition); }
1474 bool has_pending_popframe() { return (popframe_condition() & popframe_pending_bit) != 0; }
1475 bool popframe_forcing_deopt_reexecution() { return (popframe_condition() & popframe_force_deopt_reexecution_bit) != 0; }
1476 void clear_popframe_forcing_deopt_reexecution() { _popframe_condition &= ~popframe_force_deopt_reexecution_bit; }
1477 #ifdef CC_INTERP
1478 bool pop_frame_pending(void) { return ((_popframe_condition & popframe_pending_bit) != 0); }
1479 void clr_pop_frame_pending(void) { _popframe_condition = popframe_inactive; }
1480 bool pop_frame_in_process(void) { return ((_popframe_condition & popframe_processing_bit) != 0); }
1481 void set_pop_frame_in_process(void) { _popframe_condition |= popframe_processing_bit; }
1482 void clr_pop_frame_in_process(void) { _popframe_condition &= ~popframe_processing_bit; }
1483 #endif
1485 private:
1486 // Saved incoming arguments to popped frame.
1487 // Used only when popped interpreted frame returns to deoptimized frame.
1488 void* _popframe_preserved_args;
1489 int _popframe_preserved_args_size;
1491 public:
1492 void popframe_preserve_args(ByteSize size_in_bytes, void* start);
1493 void* popframe_preserved_args();
1494 ByteSize popframe_preserved_args_size();
1495 WordSize popframe_preserved_args_size_in_words();
1496 void popframe_free_preserved_args();
1499 private:
1500 JvmtiThreadState *_jvmti_thread_state;
1501 JvmtiGetLoadedClassesClosure* _jvmti_get_loaded_classes_closure;
1503 // Used by the interpreter in fullspeed mode for frame pop, method
1504 // entry, method exit and single stepping support. This field is
1505 // only set to non-zero by the VM_EnterInterpOnlyMode VM operation.
1506 // It can be set to zero asynchronously (i.e., without a VM operation
1507 // or a lock) so we have to be very careful.
1508 int _interp_only_mode;
1510 public:
1511 // used by the interpreter for fullspeed debugging support (see above)
1512 static ByteSize interp_only_mode_offset() { return byte_offset_of(JavaThread, _interp_only_mode); }
1513 bool is_interp_only_mode() { return (_interp_only_mode != 0); }
1514 int get_interp_only_mode() { return _interp_only_mode; }
1515 void increment_interp_only_mode() { ++_interp_only_mode; }
1516 void decrement_interp_only_mode() { --_interp_only_mode; }
1518 // support for cached flag that indicates whether exceptions need to be posted for this thread
1519 // if this is false, we can avoid deoptimizing when events are thrown
1520 // this gets set to reflect whether jvmtiExport::post_exception_throw would actually do anything
1521 private:
1522 int _should_post_on_exceptions_flag;
1524 public:
1525 int should_post_on_exceptions_flag() { return _should_post_on_exceptions_flag; }
1526 void set_should_post_on_exceptions_flag(int val) { _should_post_on_exceptions_flag = val; }
1528 private:
1529 ThreadStatistics *_thread_stat;
1531 public:
1532 ThreadStatistics* get_thread_stat() const { return _thread_stat; }
1534 // Return a blocker object for which this thread is blocked parking.
1535 oop current_park_blocker();
1537 private:
1538 static size_t _stack_size_at_create;
1540 public:
1541 static inline size_t stack_size_at_create(void) {
1542 return _stack_size_at_create;
1543 }
1544 static inline void set_stack_size_at_create(size_t value) {
1545 _stack_size_at_create = value;
1546 }
1548 #ifndef SERIALGC
1549 // SATB marking queue support
1550 ObjPtrQueue& satb_mark_queue() { return _satb_mark_queue; }
1551 static SATBMarkQueueSet& satb_mark_queue_set() {
1552 return _satb_mark_queue_set;
1553 }
1555 // Dirty card queue support
1556 DirtyCardQueue& dirty_card_queue() { return _dirty_card_queue; }
1557 static DirtyCardQueueSet& dirty_card_queue_set() {
1558 return _dirty_card_queue_set;
1559 }
1560 #endif // !SERIALGC
1562 // This method initializes the SATB and dirty card queues before a
1563 // JavaThread is added to the Java thread list. Right now, we don't
1564 // have to do anything to the dirty card queue (it should have been
1565 // activated when the thread was created), but we have to activate
1566 // the SATB queue if the thread is created while a marking cycle is
1567 // in progress. The activation / de-activation of the SATB queues at
1568 // the beginning / end of a marking cycle is done during safepoints
1569 // so we have to make sure this method is called outside one to be
1570 // able to safely read the active field of the SATB queue set. Right
1571 // now, it is called just before the thread is added to the Java
1572 // thread list in the Threads::add() method. That method is holding
1573 // the Threads_lock which ensures we are outside a safepoint. We
1574 // cannot do the obvious and set the active field of the SATB queue
1575 // when the thread is created given that, in some cases, safepoints
1576 // might happen between the JavaThread constructor being called and the
1577 // thread being added to the Java thread list (an example of this is
1578 // when the structure for the DestroyJavaVM thread is created).
1579 #ifndef SERIALGC
1580 void initialize_queues();
1581 #else // !SERIALGC
1582 void initialize_queues() { }
1583 #endif // !SERIALGC
1585 // Machine dependent stuff
1586 #ifdef TARGET_OS_ARCH_linux_x86
1587 # include "thread_linux_x86.hpp"
1588 #endif
1589 #ifdef TARGET_OS_ARCH_linux_sparc
1590 # include "thread_linux_sparc.hpp"
1591 #endif
1592 #ifdef TARGET_OS_ARCH_linux_zero
1593 # include "thread_linux_zero.hpp"
1594 #endif
1595 #ifdef TARGET_OS_ARCH_solaris_x86
1596 # include "thread_solaris_x86.hpp"
1597 #endif
1598 #ifdef TARGET_OS_ARCH_solaris_sparc
1599 # include "thread_solaris_sparc.hpp"
1600 #endif
1601 #ifdef TARGET_OS_ARCH_windows_x86
1602 # include "thread_windows_x86.hpp"
1603 #endif
1604 #ifdef TARGET_OS_ARCH_linux_arm
1605 # include "thread_linux_arm.hpp"
1606 #endif
1607 #ifdef TARGET_OS_ARCH_linux_ppc
1608 # include "thread_linux_ppc.hpp"
1609 #endif
1612 public:
1613 void set_blocked_on_compilation(bool value) {
1614 _blocked_on_compilation = value;
1615 }
1617 bool blocked_on_compilation() {
1618 return _blocked_on_compilation;
1619 }
1620 protected:
1621 bool _blocked_on_compilation;
1624 // JSR166 per-thread parker
1625 private:
1626 Parker* _parker;
1627 public:
1628 Parker* parker() { return _parker; }
1630 // Biased locking support
1631 private:
1632 GrowableArray<MonitorInfo*>* _cached_monitor_info;
1633 public:
1634 GrowableArray<MonitorInfo*>* cached_monitor_info() { return _cached_monitor_info; }
1635 void set_cached_monitor_info(GrowableArray<MonitorInfo*>* info) { _cached_monitor_info = info; }
1637 // clearing/querying jni attach status
1638 bool is_attaching() const { return _is_attaching; }
1639 void set_attached() { _is_attaching = false; OrderAccess::fence(); }
1640 private:
1641 // This field is used to determine if a thread has claimed
1642 // a par_id: it is -1 if the thread has not claimed a par_id;
1643 // otherwise its value is the par_id that has been claimed.
1644 int _claimed_par_id;
1645 public:
1646 int get_claimed_par_id() { return _claimed_par_id; }
1647 void set_claimed_par_id(int id) { _claimed_par_id = id;}
1648 };
1650 // Inline implementation of JavaThread::current
1651 inline JavaThread* JavaThread::current() {
1652 Thread* thread = ThreadLocalStorage::thread();
1653 assert(thread != NULL && thread->is_Java_thread(), "just checking");
1654 return (JavaThread*)thread;
1655 }
1657 inline CompilerThread* JavaThread::as_CompilerThread() {
1658 assert(is_Compiler_thread(), "just checking");
1659 return (CompilerThread*)this;
1660 }
1662 inline bool JavaThread::stack_yellow_zone_disabled() {
1663 return _stack_guard_state == stack_guard_yellow_disabled;
1664 }
1666 inline bool JavaThread::stack_yellow_zone_enabled() {
1667 #ifdef ASSERT
1668 if (os::uses_stack_guard_pages()) {
1669 assert(_stack_guard_state != stack_guard_unused, "guard pages must be in use");
1670 }
1671 #endif
1672 return _stack_guard_state == stack_guard_enabled;
1673 }
1675 inline size_t JavaThread::stack_available(address cur_sp) {
1676 // This code assumes java stacks grow down
1677 address low_addr; // Limit on the address for deepest stack depth
1678 if ( _stack_guard_state == stack_guard_unused) {
1679 low_addr = stack_base() - stack_size();
1680 } else {
1681 low_addr = stack_yellow_zone_base();
1682 }
1683 return cur_sp > low_addr ? cur_sp - low_addr : 0;
1684 }
1686 // A thread used for Compilation.
1687 class CompilerThread : public JavaThread {
1688 friend class VMStructs;
1689 private:
1690 CompilerCounters* _counters;
1692 ciEnv* _env;
1693 CompileLog* _log;
1694 CompileTask* _task;
1695 CompileQueue* _queue;
1696 BufferBlob* _buffer_blob;
1698 nmethod* _scanned_nmethod; // nmethod being scanned by the sweeper
1700 public:
1702 static CompilerThread* current();
1704 CompilerThread(CompileQueue* queue, CompilerCounters* counters);
1706 bool is_Compiler_thread() const { return true; }
1707 // Hide this compiler thread from external view.
1708 bool is_hidden_from_external_view() const { return true; }
1710 CompileQueue* queue() { return _queue; }
1711 CompilerCounters* counters() { return _counters; }
1713 // Get/set the thread's compilation environment.
1714 ciEnv* env() { return _env; }
1715 void set_env(ciEnv* env) { _env = env; }
1717 BufferBlob* get_buffer_blob() { return _buffer_blob; }
1718 void set_buffer_blob(BufferBlob* b) { _buffer_blob = b; };
1720 // Get/set the thread's logging information
1721 CompileLog* log() { return _log; }
1722 void init_log(CompileLog* log) {
1723 // Set once, for good.
1724 assert(_log == NULL, "set only once");
1725 _log = log;
1726 }
1728 // GC support
1729 // Apply "f->do_oop" to all root oops in "this".
1730 // Apply "cf->do_code_blob" (if !NULL) to all code blobs active in frames
1731 void oops_do(OopClosure* f, CodeBlobClosure* cf);
1733 #ifndef PRODUCT
1734 private:
1735 IdealGraphPrinter *_ideal_graph_printer;
1736 public:
1737 IdealGraphPrinter *ideal_graph_printer() { return _ideal_graph_printer; }
1738 void set_ideal_graph_printer(IdealGraphPrinter *n) { _ideal_graph_printer = n; }
1739 #endif
1741 // Get/set the thread's current task
1742 CompileTask* task() { return _task; }
1743 void set_task(CompileTask* task) { _task = task; }
1745 // Track the nmethod currently being scanned by the sweeper
1746 void set_scanned_nmethod(nmethod* nm) {
1747 assert(_scanned_nmethod == NULL || nm == NULL, "should reset to NULL before writing a new value");
1748 _scanned_nmethod = nm;
1749 }
1750 };
1752 inline CompilerThread* CompilerThread::current() {
1753 return JavaThread::current()->as_CompilerThread();
1754 }
1757 // The active thread queue. It also keeps track of the current used
1758 // thread priorities.
1759 class Threads: AllStatic {
1760 friend class VMStructs;
1761 private:
1762 static JavaThread* _thread_list;
1763 static int _number_of_threads;
1764 static int _number_of_non_daemon_threads;
1765 static int _return_code;
1767 public:
1768 // Thread management
1769 // force_daemon is a concession to JNI, where we may need to add a
1770 // thread to the thread list before allocating its thread object
1771 static void add(JavaThread* p, bool force_daemon = false);
1772 static void remove(JavaThread* p);
1773 static bool includes(JavaThread* p);
1774 static JavaThread* first() { return _thread_list; }
1775 static void threads_do(ThreadClosure* tc);
1777 // Initializes the vm and creates the vm thread
1778 static jint create_vm(JavaVMInitArgs* args, bool* canTryAgain);
1779 static void convert_vm_init_libraries_to_agents();
1780 static void create_vm_init_libraries();
1781 static void create_vm_init_agents();
1782 static void shutdown_vm_agents();
1783 static bool destroy_vm();
1784 // Supported VM versions via JNI
1785 // Includes JNI_VERSION_1_1
1786 static jboolean is_supported_jni_version_including_1_1(jint version);
1787 // Does not include JNI_VERSION_1_1
1788 static jboolean is_supported_jni_version(jint version);
1790 // Garbage collection
1791 static void follow_other_roots(void f(oop*));
1793 // Apply "f->do_oop" to all root oops in all threads.
1794 // This version may only be called by sequential code.
1795 static void oops_do(OopClosure* f, CodeBlobClosure* cf);
1796 // This version may be called by sequential or parallel code.
1797 static void possibly_parallel_oops_do(OopClosure* f, CodeBlobClosure* cf);
1798 // This creates a list of GCTasks, one per thread.
1799 static void create_thread_roots_tasks(GCTaskQueue* q);
1800 // This creates a list of GCTasks, one per thread, for marking objects.
1801 static void create_thread_roots_marking_tasks(GCTaskQueue* q);
1803 // Apply "f->do_oop" to roots in all threads that
1804 // are part of compiled frames
1805 static void compiled_frame_oops_do(OopClosure* f, CodeBlobClosure* cf);
1807 static void convert_hcode_pointers();
1808 static void restore_hcode_pointers();
1810 // Sweeper
1811 static void nmethods_do(CodeBlobClosure* cf);
1813 static void gc_epilogue();
1814 static void gc_prologue();
1816 // Verification
1817 static void verify();
1818 static void print_on(outputStream* st, bool print_stacks, bool internal_format, bool print_concurrent_locks);
1819 static void print(bool print_stacks, bool internal_format) {
1820 // this function is only used by debug.cpp
1821 print_on(tty, print_stacks, internal_format, false /* no concurrent lock printed */);
1822 }
1823 static void print_on_error(outputStream* st, Thread* current, char* buf, int buflen);
1825 // Get Java threads that are waiting to enter a monitor. If doLock
1826 // is true, then Threads_lock is grabbed as needed. Otherwise, the
1827 // VM needs to be at a safepoint.
1828 static GrowableArray<JavaThread*>* get_pending_threads(int count,
1829 address monitor, bool doLock);
1831 // Get owning Java thread from the monitor's owner field. If doLock
1832 // is true, then Threads_lock is grabbed as needed. Otherwise, the
1833 // VM needs to be at a safepoint.
1834 static JavaThread *owning_thread_from_monitor_owner(address owner,
1835 bool doLock);
1837 // Number of threads on the active threads list
1838 static int number_of_threads() { return _number_of_threads; }
1839 // Number of non-daemon threads on the active threads list
1840 static int number_of_non_daemon_threads() { return _number_of_non_daemon_threads; }
1842 // Deoptimizes all frames tied to marked nmethods
1843 static void deoptimized_wrt_marked_nmethods();
1845 };
1848 // Thread iterator
1849 class ThreadClosure: public StackObj {
1850 public:
1851 virtual void do_thread(Thread* thread) = 0;
1852 };
1854 class SignalHandlerMark: public StackObj {
1855 private:
1856 Thread* _thread;
1857 public:
1858 SignalHandlerMark(Thread* t) {
1859 _thread = t;
1860 if (_thread) _thread->enter_signal_handler();
1861 }
1862 ~SignalHandlerMark() {
1863 if (_thread) _thread->leave_signal_handler();
1864 _thread = NULL;
1865 }
1866 };
1869 #endif // SHARE_VM_RUNTIME_THREAD_HPP