Tue, 21 Apr 2009 23:21:04 -0700
6655646: dynamic languages need dynamically linked call sites
Summary: invokedynamic instruction (JSR 292 RI)
Reviewed-by: twisti, never
1 /*
2 * Copyright 1997-2008 Sun Microsystems, Inc. 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
20 * CA 95054 USA or visit www.sun.com if you need additional information or
21 * have any questions.
22 *
23 */
25 class ThreadSafepointState;
26 class ThreadProfiler;
28 class JvmtiThreadState;
29 class JvmtiGetLoadedClassesClosure;
30 class ThreadStatistics;
31 class ConcurrentLocksDump;
32 class ParkEvent ;
34 class ciEnv;
35 class CompileThread;
36 class CompileLog;
37 class CompileTask;
38 class CompileQueue;
39 class CompilerCounters;
40 class vframeArray;
42 class DeoptResourceMark;
43 class jvmtiDeferredLocalVariableSet;
45 class GCTaskQueue;
46 class ThreadClosure;
47 class IdealGraphPrinter;
49 // Class hierarchy
50 // - Thread
51 // - VMThread
52 // - JavaThread
53 // - WatcherThread
55 class Thread: public ThreadShadow {
56 friend class VMStructs;
57 private:
58 // Exception handling
59 // (Note: _pending_exception and friends are in ThreadShadow)
60 //oop _pending_exception; // pending exception for current thread
61 // const char* _exception_file; // file information for exception (debugging only)
62 // int _exception_line; // line information for exception (debugging only)
64 // Support for forcing alignment of thread objects for biased locking
65 void* _real_malloc_address;
66 public:
67 void* operator new(size_t size);
68 void operator delete(void* p);
69 private:
71 // ***************************************************************
72 // Suspend and resume support
73 // ***************************************************************
74 //
75 // VM suspend/resume no longer exists - it was once used for various
76 // things including safepoints but was deprecated and finally removed
77 // in Java 7. Because VM suspension was considered "internal" Java-level
78 // suspension was considered "external", and this legacy naming scheme
79 // remains.
80 //
81 // External suspend/resume requests come from JVM_SuspendThread,
82 // JVM_ResumeThread, JVMTI SuspendThread, and finally JVMTI
83 // ResumeThread. External
84 // suspend requests cause _external_suspend to be set and external
85 // resume requests cause _external_suspend to be cleared.
86 // External suspend requests do not nest on top of other external
87 // suspend requests. The higher level APIs reject suspend requests
88 // for already suspended threads.
89 //
90 // The external_suspend
91 // flag is checked by has_special_runtime_exit_condition() and java thread
92 // will self-suspend when handle_special_runtime_exit_condition() is
93 // called. Most uses of the _thread_blocked state in JavaThreads are
94 // considered the same as being externally suspended; if the blocking
95 // condition lifts, the JavaThread will self-suspend. Other places
96 // where VM checks for external_suspend include:
97 // + mutex granting (do not enter monitors when thread is suspended)
98 // + state transitions from _thread_in_native
99 //
100 // In general, java_suspend() does not wait for an external suspend
101 // request to complete. When it returns, the only guarantee is that
102 // the _external_suspend field is true.
103 //
104 // wait_for_ext_suspend_completion() is used to wait for an external
105 // suspend request to complete. External suspend requests are usually
106 // followed by some other interface call that requires the thread to
107 // be quiescent, e.g., GetCallTrace(). By moving the "wait time" into
108 // the interface that requires quiescence, we give the JavaThread a
109 // chance to self-suspend before we need it to be quiescent. This
110 // improves overall suspend/query performance.
111 //
112 // _suspend_flags controls the behavior of java_ suspend/resume.
113 // It must be set under the protection of SR_lock. Read from the flag is
114 // OK without SR_lock as long as the value is only used as a hint.
115 // (e.g., check _external_suspend first without lock and then recheck
116 // inside SR_lock and finish the suspension)
117 //
118 // _suspend_flags is also overloaded for other "special conditions" so
119 // that a single check indicates whether any special action is needed
120 // eg. for async exceptions.
121 // -------------------------------------------------------------------
122 // Notes:
123 // 1. The suspend/resume logic no longer uses ThreadState in OSThread
124 // but we still update its value to keep other part of the system (mainly
125 // JVMTI) happy. ThreadState is legacy code (see notes in
126 // osThread.hpp).
127 //
128 // 2. It would be more natural if set_external_suspend() is private and
129 // part of java_suspend(), but that probably would affect the suspend/query
130 // performance. Need more investigation on this.
131 //
133 // suspend/resume lock: used for self-suspend
134 Monitor* _SR_lock;
136 protected:
137 enum SuspendFlags {
138 // NOTE: avoid using the sign-bit as cc generates different test code
139 // when the sign-bit is used, and sometimes incorrectly - see CR 6398077
141 _external_suspend = 0x20000000U, // thread is asked to self suspend
142 _ext_suspended = 0x40000000U, // thread has self-suspended
143 _deopt_suspend = 0x10000000U, // thread needs to self suspend for deopt
145 _has_async_exception = 0x00000001U // there is a pending async exception
146 };
148 // various suspension related flags - atomically updated
149 // overloaded for async exception checking in check_special_condition_for_native_trans.
150 volatile uint32_t _suspend_flags;
152 private:
153 int _num_nested_signal;
155 public:
156 void enter_signal_handler() { _num_nested_signal++; }
157 void leave_signal_handler() { _num_nested_signal--; }
158 bool is_inside_signal_handler() const { return _num_nested_signal > 0; }
160 private:
161 // Debug tracing
162 static void trace(const char* msg, const Thread* const thread) PRODUCT_RETURN;
164 // Active_handles points to a block of handles
165 JNIHandleBlock* _active_handles;
167 // One-element thread local free list
168 JNIHandleBlock* _free_handle_block;
170 // Point to the last handle mark
171 HandleMark* _last_handle_mark;
173 // The parity of the last strong_roots iteration in which this thread was
174 // claimed as a task.
175 jint _oops_do_parity;
177 public:
178 void set_last_handle_mark(HandleMark* mark) { _last_handle_mark = mark; }
179 HandleMark* last_handle_mark() const { return _last_handle_mark; }
180 private:
182 // debug support for checking if code does allow safepoints or not
183 // GC points in the VM can happen because of allocation, invoking a VM operation, or blocking on
184 // mutex, or blocking on an object synchronizer (Java locking).
185 // If !allow_safepoint(), then an assertion failure will happen in any of the above cases
186 // If !allow_allocation(), then an assertion failure will happen during allocation
187 // (Hence, !allow_safepoint() => !allow_allocation()).
188 //
189 // The two classes No_Safepoint_Verifier and No_Allocation_Verifier are used to set these counters.
190 //
191 NOT_PRODUCT(int _allow_safepoint_count;) // If 0, thread allow a safepoint to happen
192 debug_only (int _allow_allocation_count;) // If 0, the thread is allowed to allocate oops.
194 // Record when GC is locked out via the GC_locker mechanism
195 CHECK_UNHANDLED_OOPS_ONLY(int _gc_locked_out_count;)
197 friend class No_Alloc_Verifier;
198 friend class No_Safepoint_Verifier;
199 friend class Pause_No_Safepoint_Verifier;
200 friend class ThreadLocalStorage;
201 friend class GC_locker;
203 ThreadLocalAllocBuffer _tlab; // Thread-local eden
205 int _vm_operation_started_count; // VM_Operation support
206 int _vm_operation_completed_count; // VM_Operation support
208 ObjectMonitor* _current_pending_monitor; // ObjectMonitor this thread
209 // is waiting to lock
210 bool _current_pending_monitor_is_from_java; // locking is from Java code
212 // ObjectMonitor on which this thread called Object.wait()
213 ObjectMonitor* _current_waiting_monitor;
215 // Private thread-local objectmonitor list - a simple cache organized as a SLL.
216 public:
217 ObjectMonitor * omFreeList ;
218 int omFreeCount ; // length of omFreeList
219 int omFreeProvision ; // reload chunk size
221 public:
222 enum {
223 is_definitely_current_thread = true
224 };
226 // Constructor
227 Thread();
228 virtual ~Thread();
230 // initializtion
231 void initialize_thread_local_storage();
233 // thread entry point
234 virtual void run();
236 // Testers
237 virtual bool is_VM_thread() const { return false; }
238 virtual bool is_Java_thread() const { return false; }
239 // Remove this ifdef when C1 is ported to the compiler interface.
240 virtual bool is_Compiler_thread() const { return false; }
241 virtual bool is_hidden_from_external_view() const { return false; }
242 virtual bool is_jvmti_agent_thread() const { return false; }
243 // True iff the thread can perform GC operations at a safepoint.
244 // Generally will be true only of VM thread and parallel GC WorkGang
245 // threads.
246 virtual bool is_GC_task_thread() const { return false; }
247 virtual bool is_Watcher_thread() const { return false; }
248 virtual bool is_ConcurrentGC_thread() const { return false; }
250 virtual char* name() const { return (char*)"Unknown thread"; }
252 // Returns the current thread
253 static inline Thread* current();
255 // Common thread operations
256 static void set_priority(Thread* thread, ThreadPriority priority);
257 static ThreadPriority get_priority(const Thread* const thread);
258 static void start(Thread* thread);
259 static void interrupt(Thread* thr);
260 static bool is_interrupted(Thread* thr, bool clear_interrupted);
262 Monitor* SR_lock() const { return _SR_lock; }
264 bool has_async_exception() const { return (_suspend_flags & _has_async_exception) != 0; }
266 void set_suspend_flag(SuspendFlags f) {
267 assert(sizeof(jint) == sizeof(_suspend_flags), "size mismatch");
268 uint32_t flags;
269 do {
270 flags = _suspend_flags;
271 }
272 while (Atomic::cmpxchg((jint)(flags | f),
273 (volatile jint*)&_suspend_flags,
274 (jint)flags) != (jint)flags);
275 }
276 void clear_suspend_flag(SuspendFlags f) {
277 assert(sizeof(jint) == sizeof(_suspend_flags), "size mismatch");
278 uint32_t flags;
279 do {
280 flags = _suspend_flags;
281 }
282 while (Atomic::cmpxchg((jint)(flags & ~f),
283 (volatile jint*)&_suspend_flags,
284 (jint)flags) != (jint)flags);
285 }
287 void set_has_async_exception() {
288 set_suspend_flag(_has_async_exception);
289 }
290 void clear_has_async_exception() {
291 clear_suspend_flag(_has_async_exception);
292 }
294 // Support for Unhandled Oop detection
295 #ifdef CHECK_UNHANDLED_OOPS
296 private:
297 UnhandledOops *_unhandled_oops;
298 public:
299 UnhandledOops* unhandled_oops() { return _unhandled_oops; }
300 // Mark oop safe for gc. It may be stack allocated but won't move.
301 void allow_unhandled_oop(oop *op) {
302 if (CheckUnhandledOops) unhandled_oops()->allow_unhandled_oop(op);
303 }
304 // Clear oops at safepoint so crashes point to unhandled oop violator
305 void clear_unhandled_oops() {
306 if (CheckUnhandledOops) unhandled_oops()->clear_unhandled_oops();
307 }
308 bool is_gc_locked_out() { return _gc_locked_out_count > 0; }
309 #endif // CHECK_UNHANDLED_OOPS
311 public:
312 // Installs a pending exception to be inserted later
313 static void send_async_exception(oop thread_oop, oop java_throwable);
315 // Resource area
316 ResourceArea* resource_area() const { return _resource_area; }
317 void set_resource_area(ResourceArea* area) { _resource_area = area; }
319 OSThread* osthread() const { return _osthread; }
320 void set_osthread(OSThread* thread) { _osthread = thread; }
322 // JNI handle support
323 JNIHandleBlock* active_handles() const { return _active_handles; }
324 void set_active_handles(JNIHandleBlock* block) { _active_handles = block; }
325 JNIHandleBlock* free_handle_block() const { return _free_handle_block; }
326 void set_free_handle_block(JNIHandleBlock* block) { _free_handle_block = block; }
328 // Internal handle support
329 HandleArea* handle_area() const { return _handle_area; }
330 void set_handle_area(HandleArea* area) { _handle_area = area; }
332 // Thread-Local Allocation Buffer (TLAB) support
333 ThreadLocalAllocBuffer& tlab() { return _tlab; }
334 void initialize_tlab() {
335 if (UseTLAB) {
336 tlab().initialize();
337 }
338 }
340 // VM operation support
341 int vm_operation_ticket() { return ++_vm_operation_started_count; }
342 int vm_operation_completed_count() { return _vm_operation_completed_count; }
343 void increment_vm_operation_completed_count() { _vm_operation_completed_count++; }
345 // For tracking the heavyweight monitor the thread is pending on.
346 ObjectMonitor* current_pending_monitor() {
347 return _current_pending_monitor;
348 }
349 void set_current_pending_monitor(ObjectMonitor* monitor) {
350 _current_pending_monitor = monitor;
351 }
352 void set_current_pending_monitor_is_from_java(bool from_java) {
353 _current_pending_monitor_is_from_java = from_java;
354 }
355 bool current_pending_monitor_is_from_java() {
356 return _current_pending_monitor_is_from_java;
357 }
359 // For tracking the ObjectMonitor on which this thread called Object.wait()
360 ObjectMonitor* current_waiting_monitor() {
361 return _current_waiting_monitor;
362 }
363 void set_current_waiting_monitor(ObjectMonitor* monitor) {
364 _current_waiting_monitor = monitor;
365 }
367 // GC support
368 // Apply "f->do_oop" to all root oops in "this".
369 void oops_do(OopClosure* f);
371 // Handles the parallel case for the method below.
372 private:
373 bool claim_oops_do_par_case(int collection_parity);
374 public:
375 // Requires that "collection_parity" is that of the current strong roots
376 // iteration. If "is_par" is false, sets the parity of "this" to
377 // "collection_parity", and returns "true". If "is_par" is true,
378 // uses an atomic instruction to set the current threads parity to
379 // "collection_parity", if it is not already. Returns "true" iff the
380 // calling thread does the update, this indicates that the calling thread
381 // has claimed the thread's stack as a root groop in the current
382 // collection.
383 bool claim_oops_do(bool is_par, int collection_parity) {
384 if (!is_par) {
385 _oops_do_parity = collection_parity;
386 return true;
387 } else {
388 return claim_oops_do_par_case(collection_parity);
389 }
390 }
392 // Sweeper support
393 void nmethods_do();
395 // Tells if adr belong to this thread. This is used
396 // for checking if a lock is owned by the running thread.
398 // Used by fast lock support
399 virtual bool is_lock_owned(address adr) const;
401 // Check if address is in the stack of the thread (not just for locks).
402 // Warning: the method can only be used on the running thread
403 bool is_in_stack(address adr) const;
405 // Sets this thread as starting thread. Returns failure if thread
406 // creation fails due to lack of memory, too many threads etc.
407 bool set_as_starting_thread();
409 protected:
410 // OS data associated with the thread
411 OSThread* _osthread; // Platform-specific thread information
413 // Thread local resource area for temporary allocation within the VM
414 ResourceArea* _resource_area;
416 // Thread local handle area for allocation of handles within the VM
417 HandleArea* _handle_area;
419 // Support for stack overflow handling, get_thread, etc.
420 address _stack_base;
421 size_t _stack_size;
422 uintptr_t _self_raw_id; // used by get_thread (mutable)
423 int _lgrp_id;
425 public:
426 // Stack overflow support
427 address stack_base() const { assert(_stack_base != NULL,"Sanity check"); return _stack_base; }
429 void set_stack_base(address base) { _stack_base = base; }
430 size_t stack_size() const { return _stack_size; }
431 void set_stack_size(size_t size) { _stack_size = size; }
432 void record_stack_base_and_size();
434 int lgrp_id() const { return _lgrp_id; }
435 void set_lgrp_id(int value) { _lgrp_id = value; }
437 // Printing
438 void print_on(outputStream* st) const;
439 void print() const { print_on(tty); }
440 virtual void print_on_error(outputStream* st, char* buf, int buflen) const;
442 // Debug-only code
444 #ifdef ASSERT
445 private:
446 // Deadlock detection support for Mutex locks. List of locks own by thread.
447 Monitor *_owned_locks;
448 // Mutex::set_owner_implementation is the only place where _owned_locks is modified,
449 // thus the friendship
450 friend class Mutex;
451 friend class Monitor;
453 public:
454 void print_owned_locks_on(outputStream* st) const;
455 void print_owned_locks() const { print_owned_locks_on(tty); }
456 Monitor * owned_locks() const { return _owned_locks; }
457 bool owns_locks() const { return owned_locks() != NULL; }
458 bool owns_locks_but_compiled_lock() const;
460 // Deadlock detection
461 bool allow_allocation() { return _allow_allocation_count == 0; }
462 #endif
464 void check_for_valid_safepoint_state(bool potential_vm_operation) PRODUCT_RETURN;
466 private:
467 volatile int _jvmti_env_iteration_count;
469 public:
470 void entering_jvmti_env_iteration() { ++_jvmti_env_iteration_count; }
471 void leaving_jvmti_env_iteration() { --_jvmti_env_iteration_count; }
472 bool is_inside_jvmti_env_iteration() { return _jvmti_env_iteration_count > 0; }
474 // Code generation
475 static ByteSize exception_file_offset() { return byte_offset_of(Thread, _exception_file ); }
476 static ByteSize exception_line_offset() { return byte_offset_of(Thread, _exception_line ); }
477 static ByteSize active_handles_offset() { return byte_offset_of(Thread, _active_handles ); }
479 static ByteSize stack_base_offset() { return byte_offset_of(Thread, _stack_base ); }
480 static ByteSize stack_size_offset() { return byte_offset_of(Thread, _stack_size ); }
481 static ByteSize omFreeList_offset() { return byte_offset_of(Thread, omFreeList); }
483 #define TLAB_FIELD_OFFSET(name) \
484 static ByteSize tlab_##name##_offset() { return byte_offset_of(Thread, _tlab) + ThreadLocalAllocBuffer::name##_offset(); }
486 TLAB_FIELD_OFFSET(start)
487 TLAB_FIELD_OFFSET(end)
488 TLAB_FIELD_OFFSET(top)
489 TLAB_FIELD_OFFSET(pf_top)
490 TLAB_FIELD_OFFSET(size) // desired_size
491 TLAB_FIELD_OFFSET(refill_waste_limit)
492 TLAB_FIELD_OFFSET(number_of_refills)
493 TLAB_FIELD_OFFSET(fast_refill_waste)
494 TLAB_FIELD_OFFSET(slow_allocations)
496 #undef TLAB_FIELD_OFFSET
498 public:
499 volatile intptr_t _Stalled ;
500 volatile int _TypeTag ;
501 ParkEvent * _ParkEvent ; // for synchronized()
502 ParkEvent * _SleepEvent ; // for Thread.sleep
503 ParkEvent * _MutexEvent ; // for native internal Mutex/Monitor
504 ParkEvent * _MuxEvent ; // for low-level muxAcquire-muxRelease
505 int NativeSyncRecursion ; // diagnostic
507 volatile int _OnTrap ; // Resume-at IP delta
508 jint _hashStateW ; // Marsaglia Shift-XOR thread-local RNG
509 jint _hashStateX ; // thread-specific hashCode generator state
510 jint _hashStateY ;
511 jint _hashStateZ ;
512 void * _schedctl ;
514 intptr_t _ScratchA, _ScratchB ; // Scratch locations for fast-path sync code
515 static ByteSize ScratchA_offset() { return byte_offset_of(Thread, _ScratchA ); }
516 static ByteSize ScratchB_offset() { return byte_offset_of(Thread, _ScratchB ); }
518 volatile jint rng [4] ; // RNG for spin loop
520 // Low-level leaf-lock primitives used to implement synchronization
521 // and native monitor-mutex infrastructure.
522 // Not for general synchronization use.
523 static void SpinAcquire (volatile int * Lock, const char * Name) ;
524 static void SpinRelease (volatile int * Lock) ;
525 static void muxAcquire (volatile intptr_t * Lock, const char * Name) ;
526 static void muxAcquireW (volatile intptr_t * Lock, ParkEvent * ev) ;
527 static void muxRelease (volatile intptr_t * Lock) ;
529 };
531 // Inline implementation of Thread::current()
532 // Thread::current is "hot" it's called > 128K times in the 1st 500 msecs of
533 // startup.
534 // ThreadLocalStorage::thread is warm -- it's called > 16K times in the same
535 // period. This is inlined in thread_<os_family>.inline.hpp.
537 inline Thread* Thread::current() {
538 #ifdef ASSERT
539 // This function is very high traffic. Define PARANOID to enable expensive
540 // asserts.
541 #ifdef PARANOID
542 // Signal handler should call ThreadLocalStorage::get_thread_slow()
543 Thread* t = ThreadLocalStorage::get_thread_slow();
544 assert(t != NULL && !t->is_inside_signal_handler(),
545 "Don't use Thread::current() inside signal handler");
546 #endif
547 #endif
548 Thread* thread = ThreadLocalStorage::thread();
549 assert(thread != NULL, "just checking");
550 return thread;
551 }
553 // Name support for threads. non-JavaThread subclasses with multiple
554 // uniquely named instances should derive from this.
555 class NamedThread: public Thread {
556 friend class VMStructs;
557 enum {
558 max_name_len = 64
559 };
560 private:
561 char* _name;
562 public:
563 NamedThread();
564 ~NamedThread();
565 // May only be called once per thread.
566 void set_name(const char* format, ...);
567 virtual char* name() const { return _name == NULL ? (char*)"Unknown Thread" : _name; }
568 };
570 // Worker threads are named and have an id of an assigned work.
571 class WorkerThread: public NamedThread {
572 private:
573 uint _id;
574 public:
575 WorkerThread() : _id(0) { }
576 void set_id(uint work_id) { _id = work_id; }
577 uint id() const { return _id; }
578 };
580 // A single WatcherThread is used for simulating timer interrupts.
581 class WatcherThread: public Thread {
582 friend class VMStructs;
583 public:
584 virtual void run();
586 private:
587 static WatcherThread* _watcher_thread;
589 static bool _should_terminate;
590 public:
591 enum SomeConstants {
592 delay_interval = 10 // interrupt delay in milliseconds
593 };
595 // Constructor
596 WatcherThread();
598 // Tester
599 bool is_Watcher_thread() const { return true; }
601 // Printing
602 char* name() const { return (char*)"VM Periodic Task Thread"; }
603 void print_on(outputStream* st) const;
604 void print() const { print_on(tty); }
606 // Returns the single instance of WatcherThread
607 static WatcherThread* watcher_thread() { return _watcher_thread; }
609 // Create and start the single instance of WatcherThread, or stop it on shutdown
610 static void start();
611 static void stop();
612 };
615 class CompilerThread;
617 typedef void (*ThreadFunction)(JavaThread*, TRAPS);
619 class JavaThread: public Thread {
620 friend class VMStructs;
621 private:
622 JavaThread* _next; // The next thread in the Threads list
623 oop _threadObj; // The Java level thread object
625 #ifdef ASSERT
626 private:
627 int _java_call_counter;
629 public:
630 int java_call_counter() { return _java_call_counter; }
631 void inc_java_call_counter() { _java_call_counter++; }
632 void dec_java_call_counter() {
633 assert(_java_call_counter > 0, "Invalid nesting of JavaCallWrapper");
634 _java_call_counter--;
635 }
636 private: // restore original namespace restriction
637 #endif // ifdef ASSERT
639 #ifndef PRODUCT
640 public:
641 enum {
642 jump_ring_buffer_size = 16
643 };
644 private: // restore original namespace restriction
645 #endif
647 JavaFrameAnchor _anchor; // Encapsulation of current java frame and it state
649 ThreadFunction _entry_point;
651 JNIEnv _jni_environment;
653 // Deopt support
654 DeoptResourceMark* _deopt_mark; // Holds special ResourceMark for deoptimization
656 intptr_t* _must_deopt_id; // id of frame that needs to be deopted once we
657 // transition out of native
659 vframeArray* _vframe_array_head; // Holds the heap of the active vframeArrays
660 vframeArray* _vframe_array_last; // Holds last vFrameArray we popped
661 // Because deoptimization is lazy we must save jvmti requests to set locals
662 // in compiled frames until we deoptimize and we have an interpreter frame.
663 // This holds the pointer to array (yeah like there might be more than one) of
664 // description of compiled vframes that have locals that need to be updated.
665 GrowableArray<jvmtiDeferredLocalVariableSet*>* _deferred_locals_updates;
667 // Handshake value for fixing 6243940. We need a place for the i2c
668 // adapter to store the callee methodOop. This value is NEVER live
669 // across a gc point so it does NOT have to be gc'd
670 // The handshake is open ended since we can't be certain that it will
671 // be NULLed. This is because we rarely ever see the race and end up
672 // in handle_wrong_method which is the backend of the handshake. See
673 // code in i2c adapters and handle_wrong_method.
675 methodOop _callee_target;
677 // Oop results of VM runtime calls
678 oop _vm_result; // Used to pass back an oop result into Java code, GC-preserved
679 oop _vm_result_2; // Used to pass back an oop result into Java code, GC-preserved
681 MonitorChunk* _monitor_chunks; // Contains the off stack monitors
682 // allocated during deoptimization
683 // and by JNI_MonitorEnter/Exit
685 // Async. requests support
686 enum AsyncRequests {
687 _no_async_condition = 0,
688 _async_exception,
689 _async_unsafe_access_error
690 };
691 AsyncRequests _special_runtime_exit_condition; // Enum indicating pending async. request
692 oop _pending_async_exception;
694 // Safepoint support
695 public: // Expose _thread_state for SafeFetchInt()
696 volatile JavaThreadState _thread_state;
697 private:
698 ThreadSafepointState *_safepoint_state; // Holds information about a thread during a safepoint
699 address _saved_exception_pc; // Saved pc of instruction where last implicit exception happened
701 // JavaThread termination support
702 enum TerminatedTypes {
703 _not_terminated = 0xDEAD - 2,
704 _thread_exiting, // JavaThread::exit() has been called for this thread
705 _thread_terminated, // JavaThread is removed from thread list
706 _vm_exited // JavaThread is still executing native code, but VM is terminated
707 // only VM_Exit can set _vm_exited
708 };
710 // In general a JavaThread's _terminated field transitions as follows:
711 //
712 // _not_terminated => _thread_exiting => _thread_terminated
713 //
714 // _vm_exited is a special value to cover the case of a JavaThread
715 // executing native code after the VM itself is terminated.
716 TerminatedTypes _terminated;
717 // suspend/resume support
718 volatile bool _suspend_equivalent; // Suspend equivalent condition
719 jint _in_deopt_handler; // count of deoptimization
720 // handlers thread is in
721 volatile bool _doing_unsafe_access; // Thread may fault due to unsafe access
722 bool _do_not_unlock_if_synchronized; // Do not unlock the receiver of a synchronized method (since it was
723 // never locked) when throwing an exception. Used by interpreter only.
725 // Flag to mark a JNI thread in the process of attaching - See CR 6404306
726 // This flag is never set true other than at construction, and in that case
727 // is shortly thereafter set false
728 volatile bool _is_attaching;
730 public:
731 // State of the stack guard pages for this thread.
732 enum StackGuardState {
733 stack_guard_unused, // not needed
734 stack_guard_yellow_disabled,// disabled (temporarily) after stack overflow
735 stack_guard_enabled // enabled
736 };
738 private:
740 StackGuardState _stack_guard_state;
742 // Compiler exception handling (NOTE: The _exception_oop is *NOT* the same as _pending_exception. It is
743 // used to temp. parsing values into and out of the runtime system during exception handling for compiled
744 // code)
745 volatile oop _exception_oop; // Exception thrown in compiled code
746 volatile address _exception_pc; // PC where exception happened
747 volatile address _exception_handler_pc; // PC for handler of exception
748 volatile int _exception_stack_size; // Size of frame where exception happened
750 // support for compilation
751 bool _is_compiling; // is true if a compilation is active inthis thread (one compilation per thread possible)
753 // support for JNI critical regions
754 jint _jni_active_critical; // count of entries into JNI critical region
756 // For deadlock detection.
757 int _depth_first_number;
759 // JVMTI PopFrame support
760 // This is set to popframe_pending to signal that top Java frame should be popped immediately
761 int _popframe_condition;
763 #ifndef PRODUCT
764 int _jmp_ring_index;
765 struct {
766 // We use intptr_t instead of address so debugger doesn't try and display strings
767 intptr_t _target;
768 intptr_t _instruction;
769 const char* _file;
770 int _line;
771 } _jmp_ring[ jump_ring_buffer_size ];
772 #endif /* PRODUCT */
774 #ifndef SERIALGC
775 // Support for G1 barriers
777 ObjPtrQueue _satb_mark_queue; // Thread-local log for SATB barrier.
778 // Set of all such queues.
779 static SATBMarkQueueSet _satb_mark_queue_set;
781 DirtyCardQueue _dirty_card_queue; // Thread-local log for dirty cards.
782 // Set of all such queues.
783 static DirtyCardQueueSet _dirty_card_queue_set;
785 void flush_barrier_queues();
786 #endif // !SERIALGC
788 friend class VMThread;
789 friend class ThreadWaitTransition;
790 friend class VM_Exit;
792 void initialize(); // Initialized the instance variables
794 public:
795 // Constructor
796 JavaThread(bool is_attaching = false); // for main thread and JNI attached threads
797 JavaThread(ThreadFunction entry_point, size_t stack_size = 0);
798 ~JavaThread();
800 #ifdef ASSERT
801 // verify this JavaThread hasn't be published in the Threads::list yet
802 void verify_not_published();
803 #endif
805 //JNI functiontable getter/setter for JVMTI jni function table interception API.
806 void set_jni_functions(struct JNINativeInterface_* functionTable) {
807 _jni_environment.functions = functionTable;
808 }
809 struct JNINativeInterface_* get_jni_functions() {
810 return (struct JNINativeInterface_ *)_jni_environment.functions;
811 }
813 // Executes Shutdown.shutdown()
814 void invoke_shutdown_hooks();
816 // Cleanup on thread exit
817 enum ExitType {
818 normal_exit,
819 jni_detach
820 };
821 void exit(bool destroy_vm, ExitType exit_type = normal_exit);
823 void cleanup_failed_attach_current_thread();
825 // Testers
826 virtual bool is_Java_thread() const { return true; }
828 // compilation
829 void set_is_compiling(bool f) { _is_compiling = f; }
830 bool is_compiling() const { return _is_compiling; }
832 // Thread chain operations
833 JavaThread* next() const { return _next; }
834 void set_next(JavaThread* p) { _next = p; }
836 // Thread oop. threadObj() can be NULL for initial JavaThread
837 // (or for threads attached via JNI)
838 oop threadObj() const { return _threadObj; }
839 void set_threadObj(oop p) { _threadObj = p; }
841 ThreadPriority java_priority() const; // Read from threadObj()
843 // Prepare thread and add to priority queue. If a priority is
844 // not specified, use the priority of the thread object. Threads_lock
845 // must be held while this function is called.
846 void prepare(jobject jni_thread, ThreadPriority prio=NoPriority);
848 void set_saved_exception_pc(address pc) { _saved_exception_pc = pc; }
849 address saved_exception_pc() { return _saved_exception_pc; }
852 ThreadFunction entry_point() const { return _entry_point; }
854 // Allocates a new Java level thread object for this thread. thread_name may be NULL.
855 void allocate_threadObj(Handle thread_group, char* thread_name, bool daemon, TRAPS);
857 // Last frame anchor routines
859 JavaFrameAnchor* frame_anchor(void) { return &_anchor; }
861 // last_Java_sp
862 bool has_last_Java_frame() const { return _anchor.has_last_Java_frame(); }
863 intptr_t* last_Java_sp() const { return _anchor.last_Java_sp(); }
865 // last_Java_pc
867 address last_Java_pc(void) { return _anchor.last_Java_pc(); }
869 // Safepoint support
870 JavaThreadState thread_state() const { return _thread_state; }
871 void set_thread_state(JavaThreadState s) { _thread_state=s; }
872 ThreadSafepointState *safepoint_state() const { return _safepoint_state; }
873 void set_safepoint_state(ThreadSafepointState *state) { _safepoint_state = state; }
874 bool is_at_poll_safepoint() { return _safepoint_state->is_at_poll_safepoint(); }
876 // thread has called JavaThread::exit() or is terminated
877 bool is_exiting() { return _terminated == _thread_exiting || is_terminated(); }
878 // thread is terminated (no longer on the threads list); we compare
879 // against the two non-terminated values so that a freed JavaThread
880 // will also be considered terminated.
881 bool is_terminated() { return _terminated != _not_terminated && _terminated != _thread_exiting; }
882 void set_terminated(TerminatedTypes t) { _terminated = t; }
883 // special for Threads::remove() which is static:
884 void set_terminated_value() { _terminated = _thread_terminated; }
885 void block_if_vm_exited();
887 bool doing_unsafe_access() { return _doing_unsafe_access; }
888 void set_doing_unsafe_access(bool val) { _doing_unsafe_access = val; }
890 bool do_not_unlock_if_synchronized() { return _do_not_unlock_if_synchronized; }
891 void set_do_not_unlock_if_synchronized(bool val) { _do_not_unlock_if_synchronized = val; }
894 // Suspend/resume support for JavaThread
896 private:
897 void set_ext_suspended() { set_suspend_flag (_ext_suspended); }
898 void clear_ext_suspended() { clear_suspend_flag(_ext_suspended); }
900 public:
901 void java_suspend();
902 void java_resume();
903 int java_suspend_self();
905 void check_and_wait_while_suspended() {
906 assert(JavaThread::current() == this, "sanity check");
908 bool do_self_suspend;
909 do {
910 // were we externally suspended while we were waiting?
911 do_self_suspend = handle_special_suspend_equivalent_condition();
912 if (do_self_suspend) {
913 // don't surprise the thread that suspended us by returning
914 java_suspend_self();
915 set_suspend_equivalent();
916 }
917 } while (do_self_suspend);
918 }
919 static void check_safepoint_and_suspend_for_native_trans(JavaThread *thread);
920 // Check for async exception in addition to safepoint and suspend request.
921 static void check_special_condition_for_native_trans(JavaThread *thread);
923 bool is_ext_suspend_completed(bool called_by_wait, int delay, uint32_t *bits);
924 bool is_ext_suspend_completed_with_lock(uint32_t *bits) {
925 MutexLockerEx ml(SR_lock(), Mutex::_no_safepoint_check_flag);
926 // Warning: is_ext_suspend_completed() may temporarily drop the
927 // SR_lock to allow the thread to reach a stable thread state if
928 // it is currently in a transient thread state.
929 return is_ext_suspend_completed(false /*!called_by_wait */,
930 SuspendRetryDelay, bits);
931 }
933 // We cannot allow wait_for_ext_suspend_completion() to run forever or
934 // we could hang. SuspendRetryCount and SuspendRetryDelay are normally
935 // passed as the count and delay parameters. Experiments with specific
936 // calls to wait_for_ext_suspend_completion() can be done by passing
937 // other values in the code. Experiments with all calls can be done
938 // via the appropriate -XX options.
939 bool wait_for_ext_suspend_completion(int count, int delay, uint32_t *bits);
941 void set_external_suspend() { set_suspend_flag (_external_suspend); }
942 void clear_external_suspend() { clear_suspend_flag(_external_suspend); }
944 void set_deopt_suspend() { set_suspend_flag (_deopt_suspend); }
945 void clear_deopt_suspend() { clear_suspend_flag(_deopt_suspend); }
946 bool is_deopt_suspend() { return (_suspend_flags & _deopt_suspend) != 0; }
948 bool is_external_suspend() const {
949 return (_suspend_flags & _external_suspend) != 0;
950 }
951 // Whenever a thread transitions from native to vm/java it must suspend
952 // if external|deopt suspend is present.
953 bool is_suspend_after_native() const {
954 return (_suspend_flags & (_external_suspend | _deopt_suspend) ) != 0;
955 }
957 // external suspend request is completed
958 bool is_ext_suspended() const {
959 return (_suspend_flags & _ext_suspended) != 0;
960 }
962 // legacy method that checked for either external suspension or vm suspension
963 bool is_any_suspended() const {
964 return is_ext_suspended();
965 }
967 bool is_external_suspend_with_lock() const {
968 MutexLockerEx ml(SR_lock(), Mutex::_no_safepoint_check_flag);
969 return is_external_suspend();
970 }
972 // Special method to handle a pending external suspend request
973 // when a suspend equivalent condition lifts.
974 bool handle_special_suspend_equivalent_condition() {
975 assert(is_suspend_equivalent(),
976 "should only be called in a suspend equivalence condition");
977 MutexLockerEx ml(SR_lock(), Mutex::_no_safepoint_check_flag);
978 bool ret = is_external_suspend();
979 if (!ret) {
980 // not about to self-suspend so clear suspend equivalence
981 clear_suspend_equivalent();
982 }
983 // implied else:
984 // We have a pending external suspend request so we leave the
985 // suspend_equivalent flag set until java_suspend_self() sets
986 // the ext_suspended flag and clears the suspend_equivalent
987 // flag. This insures that wait_for_ext_suspend_completion()
988 // will return consistent values.
989 return ret;
990 }
992 bool is_any_suspended_with_lock() const {
993 MutexLockerEx ml(SR_lock(), Mutex::_no_safepoint_check_flag);
994 return is_any_suspended();
995 }
996 // utility methods to see if we are doing some kind of suspension
997 bool is_being_ext_suspended() const {
998 MutexLockerEx ml(SR_lock(), Mutex::_no_safepoint_check_flag);
999 return is_ext_suspended() || is_external_suspend();
1000 }
1002 bool is_suspend_equivalent() const { return _suspend_equivalent; }
1004 void set_suspend_equivalent() { _suspend_equivalent = true; };
1005 void clear_suspend_equivalent() { _suspend_equivalent = false; };
1007 // Thread.stop support
1008 void send_thread_stop(oop throwable);
1009 AsyncRequests clear_special_runtime_exit_condition() {
1010 AsyncRequests x = _special_runtime_exit_condition;
1011 _special_runtime_exit_condition = _no_async_condition;
1012 return x;
1013 }
1015 // Are any async conditions present?
1016 bool has_async_condition() { return (_special_runtime_exit_condition != _no_async_condition); }
1018 void check_and_handle_async_exceptions(bool check_unsafe_error = true);
1020 // these next two are also used for self-suspension and async exception support
1021 void handle_special_runtime_exit_condition(bool check_asyncs = true);
1023 // Return true if JavaThread has an asynchronous condition or
1024 // if external suspension is requested.
1025 bool has_special_runtime_exit_condition() {
1026 // We call is_external_suspend() last since external suspend should
1027 // be less common. Because we don't use is_external_suspend_with_lock
1028 // it is possible that we won't see an asynchronous external suspend
1029 // request that has just gotten started, i.e., SR_lock grabbed but
1030 // _external_suspend field change either not made yet or not visible
1031 // yet. However, this is okay because the request is asynchronous and
1032 // we will see the new flag value the next time through. It's also
1033 // possible that the external suspend request is dropped after
1034 // we have checked is_external_suspend(), we will recheck its value
1035 // under SR_lock in java_suspend_self().
1036 return (_special_runtime_exit_condition != _no_async_condition) ||
1037 is_external_suspend() || is_deopt_suspend();
1038 }
1040 void set_pending_unsafe_access_error() { _special_runtime_exit_condition = _async_unsafe_access_error; }
1042 void set_pending_async_exception(oop e) {
1043 _pending_async_exception = e;
1044 _special_runtime_exit_condition = _async_exception;
1045 set_has_async_exception();
1046 }
1048 // Fast-locking support
1049 bool is_lock_owned(address adr) const;
1051 // Accessors for vframe array top
1052 // The linked list of vframe arrays are sorted on sp. This means when we
1053 // unpack the head must contain the vframe array to unpack.
1054 void set_vframe_array_head(vframeArray* value) { _vframe_array_head = value; }
1055 vframeArray* vframe_array_head() const { return _vframe_array_head; }
1057 // Side structure for defering update of java frame locals until deopt occurs
1058 GrowableArray<jvmtiDeferredLocalVariableSet*>* deferred_locals() const { return _deferred_locals_updates; }
1059 void set_deferred_locals(GrowableArray<jvmtiDeferredLocalVariableSet *>* vf) { _deferred_locals_updates = vf; }
1061 // These only really exist to make debugging deopt problems simpler
1063 void set_vframe_array_last(vframeArray* value) { _vframe_array_last = value; }
1064 vframeArray* vframe_array_last() const { return _vframe_array_last; }
1066 // The special resourceMark used during deoptimization
1068 void set_deopt_mark(DeoptResourceMark* value) { _deopt_mark = value; }
1069 DeoptResourceMark* deopt_mark(void) { return _deopt_mark; }
1071 intptr_t* must_deopt_id() { return _must_deopt_id; }
1072 void set_must_deopt_id(intptr_t* id) { _must_deopt_id = id; }
1073 void clear_must_deopt_id() { _must_deopt_id = NULL; }
1075 methodOop callee_target() const { return _callee_target; }
1076 void set_callee_target (methodOop x) { _callee_target = x; }
1078 // Oop results of vm runtime calls
1079 oop vm_result() const { return _vm_result; }
1080 void set_vm_result (oop x) { _vm_result = x; }
1082 oop vm_result_2() const { return _vm_result_2; }
1083 void set_vm_result_2 (oop x) { _vm_result_2 = x; }
1085 // Exception handling for compiled methods
1086 oop exception_oop() const { return _exception_oop; }
1087 int exception_stack_size() const { return _exception_stack_size; }
1088 address exception_pc() const { return _exception_pc; }
1089 address exception_handler_pc() const { return _exception_handler_pc; }
1091 void set_exception_oop(oop o) { _exception_oop = o; }
1092 void set_exception_pc(address a) { _exception_pc = a; }
1093 void set_exception_handler_pc(address a) { _exception_handler_pc = a; }
1094 void set_exception_stack_size(int size) { _exception_stack_size = size; }
1096 // Stack overflow support
1097 inline size_t stack_available(address cur_sp);
1098 address stack_yellow_zone_base()
1099 { return (address)(stack_base() - (stack_size() - (stack_red_zone_size() + stack_yellow_zone_size()))); }
1100 size_t stack_yellow_zone_size()
1101 { return StackYellowPages * os::vm_page_size(); }
1102 address stack_red_zone_base()
1103 { return (address)(stack_base() - (stack_size() - stack_red_zone_size())); }
1104 size_t stack_red_zone_size()
1105 { return StackRedPages * os::vm_page_size(); }
1106 bool in_stack_yellow_zone(address a)
1107 { return (a <= stack_yellow_zone_base()) && (a >= stack_red_zone_base()); }
1108 bool in_stack_red_zone(address a)
1109 { return (a <= stack_red_zone_base()) && (a >= (address)((intptr_t)stack_base() - stack_size())); }
1111 void create_stack_guard_pages();
1112 void remove_stack_guard_pages();
1114 void enable_stack_yellow_zone();
1115 void disable_stack_yellow_zone();
1116 void enable_stack_red_zone();
1117 void disable_stack_red_zone();
1119 inline bool stack_yellow_zone_disabled();
1120 inline bool stack_yellow_zone_enabled();
1122 // Attempt to reguard the stack after a stack overflow may have occurred.
1123 // Returns true if (a) guard pages are not needed on this thread, (b) the
1124 // pages are already guarded, or (c) the pages were successfully reguarded.
1125 // Returns false if there is not enough stack space to reguard the pages, in
1126 // which case the caller should unwind a frame and try again. The argument
1127 // should be the caller's (approximate) sp.
1128 bool reguard_stack(address cur_sp);
1129 // Similar to above but see if current stackpoint is out of the guard area
1130 // and reguard if possible.
1131 bool reguard_stack(void);
1133 // Misc. accessors/mutators
1134 void set_do_not_unlock(void) { _do_not_unlock_if_synchronized = true; }
1135 void clr_do_not_unlock(void) { _do_not_unlock_if_synchronized = false; }
1136 bool do_not_unlock(void) { return _do_not_unlock_if_synchronized; }
1138 #ifndef PRODUCT
1139 void record_jump(address target, address instr, const char* file, int line);
1140 #endif /* PRODUCT */
1142 // For assembly stub generation
1143 static ByteSize threadObj_offset() { return byte_offset_of(JavaThread, _threadObj ); }
1144 #ifndef PRODUCT
1145 static ByteSize jmp_ring_index_offset() { return byte_offset_of(JavaThread, _jmp_ring_index ); }
1146 static ByteSize jmp_ring_offset() { return byte_offset_of(JavaThread, _jmp_ring ); }
1147 #endif /* PRODUCT */
1148 static ByteSize jni_environment_offset() { return byte_offset_of(JavaThread, _jni_environment ); }
1149 static ByteSize last_Java_sp_offset() {
1150 return byte_offset_of(JavaThread, _anchor) + JavaFrameAnchor::last_Java_sp_offset();
1151 }
1152 static ByteSize last_Java_pc_offset() {
1153 return byte_offset_of(JavaThread, _anchor) + JavaFrameAnchor::last_Java_pc_offset();
1154 }
1155 static ByteSize frame_anchor_offset() {
1156 return byte_offset_of(JavaThread, _anchor);
1157 }
1158 static ByteSize callee_target_offset() { return byte_offset_of(JavaThread, _callee_target ); }
1159 static ByteSize vm_result_offset() { return byte_offset_of(JavaThread, _vm_result ); }
1160 static ByteSize vm_result_2_offset() { return byte_offset_of(JavaThread, _vm_result_2 ); }
1161 static ByteSize thread_state_offset() { return byte_offset_of(JavaThread, _thread_state ); }
1162 static ByteSize saved_exception_pc_offset() { return byte_offset_of(JavaThread, _saved_exception_pc ); }
1163 static ByteSize osthread_offset() { return byte_offset_of(JavaThread, _osthread ); }
1164 static ByteSize exception_oop_offset() { return byte_offset_of(JavaThread, _exception_oop ); }
1165 static ByteSize exception_pc_offset() { return byte_offset_of(JavaThread, _exception_pc ); }
1166 static ByteSize exception_handler_pc_offset() { return byte_offset_of(JavaThread, _exception_handler_pc); }
1167 static ByteSize exception_stack_size_offset() { return byte_offset_of(JavaThread, _exception_stack_size); }
1168 static ByteSize stack_guard_state_offset() { return byte_offset_of(JavaThread, _stack_guard_state ); }
1169 static ByteSize suspend_flags_offset() { return byte_offset_of(JavaThread, _suspend_flags ); }
1171 static ByteSize do_not_unlock_if_synchronized_offset() { return byte_offset_of(JavaThread, _do_not_unlock_if_synchronized); }
1173 #ifndef SERIALGC
1174 static ByteSize satb_mark_queue_offset() { return byte_offset_of(JavaThread, _satb_mark_queue); }
1175 static ByteSize dirty_card_queue_offset() { return byte_offset_of(JavaThread, _dirty_card_queue); }
1176 #endif // !SERIALGC
1178 // Returns the jni environment for this thread
1179 JNIEnv* jni_environment() { return &_jni_environment; }
1181 static JavaThread* thread_from_jni_environment(JNIEnv* env) {
1182 JavaThread *thread_from_jni_env = (JavaThread*)((intptr_t)env - in_bytes(jni_environment_offset()));
1183 // Only return NULL if thread is off the thread list; starting to
1184 // exit should not return NULL.
1185 if (thread_from_jni_env->is_terminated()) {
1186 thread_from_jni_env->block_if_vm_exited();
1187 return NULL;
1188 } else {
1189 return thread_from_jni_env;
1190 }
1191 }
1193 // JNI critical regions. These can nest.
1194 bool in_critical() { return _jni_active_critical > 0; }
1195 void enter_critical() { assert(Thread::current() == this,
1196 "this must be current thread");
1197 _jni_active_critical++; }
1198 void exit_critical() { assert(Thread::current() == this,
1199 "this must be current thread");
1200 _jni_active_critical--;
1201 assert(_jni_active_critical >= 0,
1202 "JNI critical nesting problem?"); }
1204 // For deadlock detection
1205 int depth_first_number() { return _depth_first_number; }
1206 void set_depth_first_number(int dfn) { _depth_first_number = dfn; }
1208 private:
1209 void set_monitor_chunks(MonitorChunk* monitor_chunks) { _monitor_chunks = monitor_chunks; }
1211 public:
1212 MonitorChunk* monitor_chunks() const { return _monitor_chunks; }
1213 void add_monitor_chunk(MonitorChunk* chunk);
1214 void remove_monitor_chunk(MonitorChunk* chunk);
1215 bool in_deopt_handler() const { return _in_deopt_handler > 0; }
1216 void inc_in_deopt_handler() { _in_deopt_handler++; }
1217 void dec_in_deopt_handler() {
1218 assert(_in_deopt_handler > 0, "mismatched deopt nesting");
1219 if (_in_deopt_handler > 0) { // robustness
1220 _in_deopt_handler--;
1221 }
1222 }
1224 private:
1225 void set_entry_point(ThreadFunction entry_point) { _entry_point = entry_point; }
1227 public:
1229 // Frame iteration; calls the function f for all frames on the stack
1230 void frames_do(void f(frame*, const RegisterMap*));
1232 // Memory operations
1233 void oops_do(OopClosure* f);
1235 // Sweeper operations
1236 void nmethods_do();
1238 // Memory management operations
1239 void gc_epilogue();
1240 void gc_prologue();
1242 // Misc. operations
1243 char* name() const { return (char*)get_thread_name(); }
1244 void print_on(outputStream* st) const;
1245 void print() const { print_on(tty); }
1246 void print_value();
1247 void print_thread_state_on(outputStream* ) const PRODUCT_RETURN;
1248 void print_thread_state() const PRODUCT_RETURN;
1249 void print_on_error(outputStream* st, char* buf, int buflen) const;
1250 void verify();
1251 const char* get_thread_name() const;
1252 private:
1253 // factor out low-level mechanics for use in both normal and error cases
1254 const char* get_thread_name_string(char* buf = NULL, int buflen = 0) const;
1255 public:
1256 const char* get_threadgroup_name() const;
1257 const char* get_parent_name() const;
1259 // Accessing frames
1260 frame last_frame() {
1261 _anchor.make_walkable(this);
1262 return pd_last_frame();
1263 }
1264 javaVFrame* last_java_vframe(RegisterMap* reg_map);
1266 // Returns method at 'depth' java or native frames down the stack
1267 // Used for security checks
1268 klassOop security_get_caller_class(int depth);
1270 // Print stack trace in external format
1271 void print_stack_on(outputStream* st);
1272 void print_stack() { print_stack_on(tty); }
1274 // Print stack traces in various internal formats
1275 void trace_stack() PRODUCT_RETURN;
1276 void trace_stack_from(vframe* start_vf) PRODUCT_RETURN;
1277 void trace_frames() PRODUCT_RETURN;
1279 // Returns the number of stack frames on the stack
1280 int depth() const;
1282 // Function for testing deoptimization
1283 void deoptimize();
1284 void make_zombies();
1286 void deoptimized_wrt_marked_nmethods();
1288 // Profiling operation (see fprofile.cpp)
1289 public:
1290 bool profile_last_Java_frame(frame* fr);
1292 private:
1293 ThreadProfiler* _thread_profiler;
1294 private:
1295 friend class FlatProfiler; // uses both [gs]et_thread_profiler.
1296 friend class FlatProfilerTask; // uses get_thread_profiler.
1297 friend class ThreadProfilerMark; // uses get_thread_profiler.
1298 ThreadProfiler* get_thread_profiler() { return _thread_profiler; }
1299 ThreadProfiler* set_thread_profiler(ThreadProfiler* tp) {
1300 ThreadProfiler* result = _thread_profiler;
1301 _thread_profiler = tp;
1302 return result;
1303 }
1305 // Static operations
1306 public:
1307 // Returns the running thread as a JavaThread
1308 static inline JavaThread* current();
1310 // Returns the active Java thread. Do not use this if you know you are calling
1311 // from a JavaThread, as it's slower than JavaThread::current. If called from
1312 // the VMThread, it also returns the JavaThread that instigated the VMThread's
1313 // operation. You may not want that either.
1314 static JavaThread* active();
1316 inline CompilerThread* as_CompilerThread();
1318 public:
1319 virtual void run();
1320 void thread_main_inner();
1322 private:
1323 // PRIVILEGED STACK
1324 PrivilegedElement* _privileged_stack_top;
1325 GrowableArray<oop>* _array_for_gc;
1326 public:
1328 // Returns the privileged_stack information.
1329 PrivilegedElement* privileged_stack_top() const { return _privileged_stack_top; }
1330 void set_privileged_stack_top(PrivilegedElement *e) { _privileged_stack_top = e; }
1331 void register_array_for_gc(GrowableArray<oop>* array) { _array_for_gc = array; }
1333 public:
1334 // Thread local information maintained by JVMTI.
1335 void set_jvmti_thread_state(JvmtiThreadState *value) { _jvmti_thread_state = value; }
1336 // A JvmtiThreadState is lazily allocated. This jvmti_thread_state()
1337 // getter is used to get this JavaThread's JvmtiThreadState if it has
1338 // one which means NULL can be returned. JvmtiThreadState::state_for()
1339 // is used to get the specified JavaThread's JvmtiThreadState if it has
1340 // one or it allocates a new JvmtiThreadState for the JavaThread and
1341 // returns it. JvmtiThreadState::state_for() will return NULL only if
1342 // the specified JavaThread is exiting.
1343 JvmtiThreadState *jvmti_thread_state() const { return _jvmti_thread_state; }
1344 static ByteSize jvmti_thread_state_offset() { return byte_offset_of(JavaThread, _jvmti_thread_state); }
1345 void set_jvmti_get_loaded_classes_closure(JvmtiGetLoadedClassesClosure* value) { _jvmti_get_loaded_classes_closure = value; }
1346 JvmtiGetLoadedClassesClosure* get_jvmti_get_loaded_classes_closure() const { return _jvmti_get_loaded_classes_closure; }
1348 // JVMTI PopFrame support
1349 // Setting and clearing popframe_condition
1350 // All of these enumerated values are bits. popframe_pending
1351 // indicates that a PopFrame() has been requested and not yet been
1352 // completed. popframe_processing indicates that that PopFrame() is in
1353 // the process of being completed. popframe_force_deopt_reexecution_bit
1354 // indicates that special handling is required when returning to a
1355 // deoptimized caller.
1356 enum PopCondition {
1357 popframe_inactive = 0x00,
1358 popframe_pending_bit = 0x01,
1359 popframe_processing_bit = 0x02,
1360 popframe_force_deopt_reexecution_bit = 0x04
1361 };
1362 PopCondition popframe_condition() { return (PopCondition) _popframe_condition; }
1363 void set_popframe_condition(PopCondition c) { _popframe_condition = c; }
1364 void set_popframe_condition_bit(PopCondition c) { _popframe_condition |= c; }
1365 void clear_popframe_condition() { _popframe_condition = popframe_inactive; }
1366 static ByteSize popframe_condition_offset() { return byte_offset_of(JavaThread, _popframe_condition); }
1367 bool has_pending_popframe() { return (popframe_condition() & popframe_pending_bit) != 0; }
1368 bool popframe_forcing_deopt_reexecution() { return (popframe_condition() & popframe_force_deopt_reexecution_bit) != 0; }
1369 void clear_popframe_forcing_deopt_reexecution() { _popframe_condition &= ~popframe_force_deopt_reexecution_bit; }
1370 #ifdef CC_INTERP
1371 bool pop_frame_pending(void) { return ((_popframe_condition & popframe_pending_bit) != 0); }
1372 void clr_pop_frame_pending(void) { _popframe_condition = popframe_inactive; }
1373 bool pop_frame_in_process(void) { return ((_popframe_condition & popframe_processing_bit) != 0); }
1374 void set_pop_frame_in_process(void) { _popframe_condition |= popframe_processing_bit; }
1375 void clr_pop_frame_in_process(void) { _popframe_condition &= ~popframe_processing_bit; }
1376 #endif
1378 private:
1379 // Saved incoming arguments to popped frame.
1380 // Used only when popped interpreted frame returns to deoptimized frame.
1381 void* _popframe_preserved_args;
1382 int _popframe_preserved_args_size;
1384 public:
1385 void popframe_preserve_args(ByteSize size_in_bytes, void* start);
1386 void* popframe_preserved_args();
1387 ByteSize popframe_preserved_args_size();
1388 WordSize popframe_preserved_args_size_in_words();
1389 void popframe_free_preserved_args();
1392 private:
1393 JvmtiThreadState *_jvmti_thread_state;
1394 JvmtiGetLoadedClassesClosure* _jvmti_get_loaded_classes_closure;
1396 // Used by the interpreter in fullspeed mode for frame pop, method
1397 // entry, method exit and single stepping support. This field is
1398 // only set to non-zero by the VM_EnterInterpOnlyMode VM operation.
1399 // It can be set to zero asynchronously (i.e., without a VM operation
1400 // or a lock) so we have to be very careful.
1401 int _interp_only_mode;
1403 public:
1404 // used by the interpreter for fullspeed debugging support (see above)
1405 static ByteSize interp_only_mode_offset() { return byte_offset_of(JavaThread, _interp_only_mode); }
1406 bool is_interp_only_mode() { return (_interp_only_mode != 0); }
1407 int get_interp_only_mode() { return _interp_only_mode; }
1408 void increment_interp_only_mode() { ++_interp_only_mode; }
1409 void decrement_interp_only_mode() { --_interp_only_mode; }
1411 private:
1412 ThreadStatistics *_thread_stat;
1414 public:
1415 ThreadStatistics* get_thread_stat() const { return _thread_stat; }
1417 // Return a blocker object for which this thread is blocked parking.
1418 oop current_park_blocker();
1420 private:
1421 static size_t _stack_size_at_create;
1423 public:
1424 static inline size_t stack_size_at_create(void) {
1425 return _stack_size_at_create;
1426 }
1427 static inline void set_stack_size_at_create(size_t value) {
1428 _stack_size_at_create = value;
1429 }
1431 #ifndef SERIALGC
1432 // SATB marking queue support
1433 ObjPtrQueue& satb_mark_queue() { return _satb_mark_queue; }
1434 static SATBMarkQueueSet& satb_mark_queue_set() {
1435 return _satb_mark_queue_set;
1436 }
1438 // Dirty card queue support
1439 DirtyCardQueue& dirty_card_queue() { return _dirty_card_queue; }
1440 static DirtyCardQueueSet& dirty_card_queue_set() {
1441 return _dirty_card_queue_set;
1442 }
1443 #endif // !SERIALGC
1445 // Machine dependent stuff
1446 #include "incls/_thread_pd.hpp.incl"
1448 public:
1449 void set_blocked_on_compilation(bool value) {
1450 _blocked_on_compilation = value;
1451 }
1453 bool blocked_on_compilation() {
1454 return _blocked_on_compilation;
1455 }
1456 protected:
1457 bool _blocked_on_compilation;
1460 // JSR166 per-thread parker
1461 private:
1462 Parker* _parker;
1463 public:
1464 Parker* parker() { return _parker; }
1466 // Biased locking support
1467 private:
1468 GrowableArray<MonitorInfo*>* _cached_monitor_info;
1469 public:
1470 GrowableArray<MonitorInfo*>* cached_monitor_info() { return _cached_monitor_info; }
1471 void set_cached_monitor_info(GrowableArray<MonitorInfo*>* info) { _cached_monitor_info = info; }
1473 // clearing/querying jni attach status
1474 bool is_attaching() const { return _is_attaching; }
1475 void set_attached() { _is_attaching = false; OrderAccess::fence(); }
1476 private:
1477 // This field is used to determine if a thread has claimed
1478 // a par_id: it is -1 if the thread has not claimed a par_id;
1479 // otherwise its value is the par_id that has been claimed.
1480 int _claimed_par_id;
1481 public:
1482 int get_claimed_par_id() { return _claimed_par_id; }
1483 void set_claimed_par_id(int id) { _claimed_par_id = id;}
1484 };
1486 // Inline implementation of JavaThread::current
1487 inline JavaThread* JavaThread::current() {
1488 Thread* thread = ThreadLocalStorage::thread();
1489 assert(thread != NULL && thread->is_Java_thread(), "just checking");
1490 return (JavaThread*)thread;
1491 }
1493 inline CompilerThread* JavaThread::as_CompilerThread() {
1494 assert(is_Compiler_thread(), "just checking");
1495 return (CompilerThread*)this;
1496 }
1498 inline bool JavaThread::stack_yellow_zone_disabled() {
1499 return _stack_guard_state == stack_guard_yellow_disabled;
1500 }
1502 inline bool JavaThread::stack_yellow_zone_enabled() {
1503 #ifdef ASSERT
1504 if (os::uses_stack_guard_pages()) {
1505 assert(_stack_guard_state != stack_guard_unused, "guard pages must be in use");
1506 }
1507 #endif
1508 return _stack_guard_state == stack_guard_enabled;
1509 }
1511 inline size_t JavaThread::stack_available(address cur_sp) {
1512 // This code assumes java stacks grow down
1513 address low_addr; // Limit on the address for deepest stack depth
1514 if ( _stack_guard_state == stack_guard_unused) {
1515 low_addr = stack_base() - stack_size();
1516 } else {
1517 low_addr = stack_yellow_zone_base();
1518 }
1519 return cur_sp > low_addr ? cur_sp - low_addr : 0;
1520 }
1522 // A JavaThread for low memory detection support
1523 class LowMemoryDetectorThread : public JavaThread {
1524 friend class VMStructs;
1525 public:
1526 LowMemoryDetectorThread(ThreadFunction entry_point) : JavaThread(entry_point) {};
1528 // Hide this thread from external view.
1529 bool is_hidden_from_external_view() const { return true; }
1530 };
1532 // A thread used for Compilation.
1533 class CompilerThread : public JavaThread {
1534 friend class VMStructs;
1535 private:
1536 CompilerCounters* _counters;
1538 ciEnv* _env;
1539 CompileLog* _log;
1540 CompileTask* _task;
1541 CompileQueue* _queue;
1543 public:
1545 static CompilerThread* current();
1547 CompilerThread(CompileQueue* queue, CompilerCounters* counters);
1549 bool is_Compiler_thread() const { return true; }
1550 // Hide this compiler thread from external view.
1551 bool is_hidden_from_external_view() const { return true; }
1553 CompileQueue* queue() { return _queue; }
1554 CompilerCounters* counters() { return _counters; }
1556 // Get/set the thread's compilation environment.
1557 ciEnv* env() { return _env; }
1558 void set_env(ciEnv* env) { _env = env; }
1560 // Get/set the thread's logging information
1561 CompileLog* log() { return _log; }
1562 void init_log(CompileLog* log) {
1563 // Set once, for good.
1564 assert(_log == NULL, "set only once");
1565 _log = log;
1566 }
1568 #ifndef PRODUCT
1569 private:
1570 IdealGraphPrinter *_ideal_graph_printer;
1571 public:
1572 IdealGraphPrinter *ideal_graph_printer() { return _ideal_graph_printer; }
1573 void set_ideal_graph_printer(IdealGraphPrinter *n) { _ideal_graph_printer = n; }
1574 #endif
1576 // Get/set the thread's current task
1577 CompileTask* task() { return _task; }
1578 void set_task(CompileTask* task) { _task = task; }
1579 };
1581 inline CompilerThread* CompilerThread::current() {
1582 return JavaThread::current()->as_CompilerThread();
1583 }
1586 // The active thread queue. It also keeps track of the current used
1587 // thread priorities.
1588 class Threads: AllStatic {
1589 friend class VMStructs;
1590 private:
1591 static JavaThread* _thread_list;
1592 static int _number_of_threads;
1593 static int _number_of_non_daemon_threads;
1594 static int _return_code;
1596 public:
1597 // Thread management
1598 // force_daemon is a concession to JNI, where we may need to add a
1599 // thread to the thread list before allocating its thread object
1600 static void add(JavaThread* p, bool force_daemon = false);
1601 static void remove(JavaThread* p);
1602 static bool includes(JavaThread* p);
1603 static JavaThread* first() { return _thread_list; }
1604 static void threads_do(ThreadClosure* tc);
1606 // Initializes the vm and creates the vm thread
1607 static jint create_vm(JavaVMInitArgs* args, bool* canTryAgain);
1608 static void convert_vm_init_libraries_to_agents();
1609 static void create_vm_init_libraries();
1610 static void create_vm_init_agents();
1611 static void shutdown_vm_agents();
1612 static bool destroy_vm();
1613 // Supported VM versions via JNI
1614 // Includes JNI_VERSION_1_1
1615 static jboolean is_supported_jni_version_including_1_1(jint version);
1616 // Does not include JNI_VERSION_1_1
1617 static jboolean is_supported_jni_version(jint version);
1619 // Garbage collection
1620 static void follow_other_roots(void f(oop*));
1622 // Apply "f->do_oop" to all root oops in all threads.
1623 // This version may only be called by sequential code.
1624 static void oops_do(OopClosure* f);
1625 // This version may be called by sequential or parallel code.
1626 static void possibly_parallel_oops_do(OopClosure* f);
1627 // This creates a list of GCTasks, one per thread.
1628 static void create_thread_roots_tasks(GCTaskQueue* q);
1629 // This creates a list of GCTasks, one per thread, for marking objects.
1630 static void create_thread_roots_marking_tasks(GCTaskQueue* q);
1632 // Apply "f->do_oop" to roots in all threads that
1633 // are part of compiled frames
1634 static void compiled_frame_oops_do(OopClosure* f);
1636 static void convert_hcode_pointers();
1637 static void restore_hcode_pointers();
1639 // Sweeper
1640 static void nmethods_do();
1642 static void gc_epilogue();
1643 static void gc_prologue();
1645 // Verification
1646 static void verify();
1647 static void print_on(outputStream* st, bool print_stacks, bool internal_format, bool print_concurrent_locks);
1648 static void print(bool print_stacks, bool internal_format) {
1649 // this function is only used by debug.cpp
1650 print_on(tty, print_stacks, internal_format, false /* no concurrent lock printed */);
1651 }
1652 static void print_on_error(outputStream* st, Thread* current, char* buf, int buflen);
1654 // Get Java threads that are waiting to enter a monitor. If doLock
1655 // is true, then Threads_lock is grabbed as needed. Otherwise, the
1656 // VM needs to be at a safepoint.
1657 static GrowableArray<JavaThread*>* get_pending_threads(int count,
1658 address monitor, bool doLock);
1660 // Get owning Java thread from the monitor's owner field. If doLock
1661 // is true, then Threads_lock is grabbed as needed. Otherwise, the
1662 // VM needs to be at a safepoint.
1663 static JavaThread *owning_thread_from_monitor_owner(address owner,
1664 bool doLock);
1666 // Number of threads on the active threads list
1667 static int number_of_threads() { return _number_of_threads; }
1668 // Number of non-daemon threads on the active threads list
1669 static int number_of_non_daemon_threads() { return _number_of_non_daemon_threads; }
1671 // Deoptimizes all frames tied to marked nmethods
1672 static void deoptimized_wrt_marked_nmethods();
1674 };
1677 // Thread iterator
1678 class ThreadClosure: public StackObj {
1679 public:
1680 virtual void do_thread(Thread* thread) = 0;
1681 };
1683 class SignalHandlerMark: public StackObj {
1684 private:
1685 Thread* _thread;
1686 public:
1687 SignalHandlerMark(Thread* t) {
1688 _thread = t;
1689 if (_thread) _thread->enter_signal_handler();
1690 }
1691 ~SignalHandlerMark() {
1692 if (_thread) _thread->leave_signal_handler();
1693 _thread = NULL;
1694 }
1695 };
1697 // ParkEvents are type-stable and immortal.
1698 //
1699 // Lifecycle: Once a ParkEvent is associated with a thread that ParkEvent remains
1700 // associated with the thread for the thread's entire lifetime - the relationship is
1701 // stable. A thread will be associated at most one ParkEvent. When the thread
1702 // expires, the ParkEvent moves to the EventFreeList. New threads attempt to allocate from
1703 // the EventFreeList before creating a new Event. Type-stability frees us from
1704 // worrying about stale Event or Thread references in the objectMonitor subsystem.
1705 // (A reference to ParkEvent is always valid, even though the event may no longer be associated
1706 // with the desired or expected thread. A key aspect of this design is that the callers of
1707 // park, unpark, etc must tolerate stale references and spurious wakeups).
1708 //
1709 // Only the "associated" thread can block (park) on the ParkEvent, although
1710 // any other thread can unpark a reachable parkevent. Park() is allowed to
1711 // return spuriously. In fact park-unpark a really just an optimization to
1712 // avoid unbounded spinning and surrender the CPU to be a polite system citizen.
1713 // A degenerate albeit "impolite" park-unpark implementation could simply return.
1714 // See http://blogs.sun.com/dave for more details.
1715 //
1716 // Eventually I'd like to eliminate Events and ObjectWaiters, both of which serve as
1717 // thread proxies, and simply make the THREAD structure type-stable and persistent.
1718 // Currently, we unpark events associated with threads, but ideally we'd just
1719 // unpark threads.
1720 //
1721 // The base-class, PlatformEvent, is platform-specific while the ParkEvent is
1722 // platform-independent. PlatformEvent provides park(), unpark(), etc., and
1723 // is abstract -- that is, a PlatformEvent should never be instantiated except
1724 // as part of a ParkEvent.
1725 // Equivalently we could have defined a platform-independent base-class that
1726 // exported Allocate(), Release(), etc. The platform-specific class would extend
1727 // that base-class, adding park(), unpark(), etc.
1728 //
1729 // A word of caution: The JVM uses 2 very similar constructs:
1730 // 1. ParkEvent are used for Java-level "monitor" synchronization.
1731 // 2. Parkers are used by JSR166-JUC park-unpark.
1732 //
1733 // We'll want to eventually merge these redundant facilities and use ParkEvent.
1736 class ParkEvent : public os::PlatformEvent {
1737 private:
1738 ParkEvent * FreeNext ;
1740 // Current association
1741 Thread * AssociatedWith ;
1742 intptr_t RawThreadIdentity ; // LWPID etc
1743 volatile int Incarnation ;
1745 // diagnostic : keep track of last thread to wake this thread.
1746 // this is useful for construction of dependency graphs.
1747 void * LastWaker ;
1749 public:
1750 // MCS-CLH list linkage and Native Mutex/Monitor
1751 ParkEvent * volatile ListNext ;
1752 ParkEvent * volatile ListPrev ;
1753 volatile intptr_t OnList ;
1754 volatile int TState ;
1755 volatile int Notified ; // for native monitor construct
1756 volatile int IsWaiting ; // Enqueued on WaitSet
1759 private:
1760 static ParkEvent * volatile FreeList ;
1761 static volatile int ListLock ;
1763 // It's prudent to mark the dtor as "private"
1764 // ensuring that it's not visible outside the package.
1765 // Unfortunately gcc warns about such usage, so
1766 // we revert to the less desirable "protected" visibility.
1767 // The other compilers accept private dtors.
1769 protected: // Ensure dtor is never invoked
1770 ~ParkEvent() { guarantee (0, "invariant") ; }
1772 ParkEvent() : PlatformEvent() {
1773 AssociatedWith = NULL ;
1774 FreeNext = NULL ;
1775 ListNext = NULL ;
1776 ListPrev = NULL ;
1777 OnList = 0 ;
1778 TState = 0 ;
1779 Notified = 0 ;
1780 IsWaiting = 0 ;
1781 }
1783 // We use placement-new to force ParkEvent instances to be
1784 // aligned on 256-byte address boundaries. This ensures that the least
1785 // significant byte of a ParkEvent address is always 0.
1787 void * operator new (size_t sz) ;
1788 void operator delete (void * a) ;
1790 public:
1791 static ParkEvent * Allocate (Thread * t) ;
1792 static void Release (ParkEvent * e) ;
1793 } ;