2
* Copyright (c) 1997, 2024, Oracle and/or its affiliates. All rights reserved.
3
* Copyright (c) 2021, Azul Systems, Inc. All rights reserved.
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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
6
* This code is free software; you can redistribute it and/or modify it
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* under the terms of the GNU General Public License version 2 only, as
8
* published by the Free Software Foundation.
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* This code is distributed in the hope that it will be useful, but WITHOUT
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* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
13
* version 2 for more details (a copy is included in the LICENSE file that
14
* accompanied this code).
16
* You should have received a copy of the GNU General Public License version
17
* 2 along with this work; if not, write to the Free Software Foundation,
18
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
21
* or visit www.oracle.com if you need additional information or have any
26
#include "precompiled.hpp"
27
#include "cds/dynamicArchive.hpp"
28
#include "ci/ciEnv.hpp"
29
#include "classfile/javaClasses.inline.hpp"
30
#include "classfile/javaThreadStatus.hpp"
31
#include "classfile/systemDictionary.hpp"
32
#include "classfile/vmClasses.hpp"
33
#include "classfile/vmSymbols.hpp"
34
#include "code/codeCache.hpp"
35
#include "code/scopeDesc.hpp"
36
#include "compiler/compileTask.hpp"
37
#include "compiler/compilerThread.hpp"
38
#include "gc/shared/oopStorage.hpp"
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#include "gc/shared/oopStorageSet.hpp"
40
#include "gc/shared/tlab_globals.hpp"
41
#include "jfr/jfrEvents.hpp"
43
#include "jvmtifiles/jvmtiEnv.hpp"
44
#include "logging/log.hpp"
45
#include "logging/logAsyncWriter.hpp"
46
#include "logging/logStream.hpp"
47
#include "memory/allocation.inline.hpp"
48
#include "memory/iterator.hpp"
49
#include "memory/universe.hpp"
50
#include "oops/access.inline.hpp"
51
#include "oops/instanceKlass.hpp"
52
#include "oops/klass.inline.hpp"
53
#include "oops/oop.inline.hpp"
54
#include "oops/oopHandle.inline.hpp"
55
#include "oops/verifyOopClosure.hpp"
56
#include "prims/jvm_misc.hpp"
57
#include "prims/jvmtiDeferredUpdates.hpp"
58
#include "prims/jvmtiExport.hpp"
59
#include "prims/jvmtiThreadState.inline.hpp"
60
#include "runtime/atomic.hpp"
61
#include "runtime/continuation.hpp"
62
#include "runtime/continuationEntry.inline.hpp"
63
#include "runtime/continuationHelper.inline.hpp"
64
#include "runtime/deoptimization.hpp"
65
#include "runtime/frame.inline.hpp"
66
#include "runtime/handles.inline.hpp"
67
#include "runtime/handshake.hpp"
68
#include "runtime/interfaceSupport.inline.hpp"
69
#include "runtime/java.hpp"
70
#include "runtime/javaCalls.hpp"
71
#include "runtime/javaThread.inline.hpp"
72
#include "runtime/jniHandles.inline.hpp"
73
#include "runtime/lockStack.inline.hpp"
74
#include "runtime/mutexLocker.hpp"
75
#include "runtime/orderAccess.hpp"
76
#include "runtime/os.inline.hpp"
77
#include "runtime/osThread.hpp"
78
#include "runtime/safepoint.hpp"
79
#include "runtime/safepointMechanism.inline.hpp"
80
#include "runtime/safepointVerifiers.hpp"
81
#include "runtime/serviceThread.hpp"
82
#include "runtime/stackFrameStream.inline.hpp"
83
#include "runtime/stackWatermarkSet.hpp"
84
#include "runtime/synchronizer.hpp"
85
#include "runtime/threadCritical.hpp"
86
#include "runtime/threadSMR.inline.hpp"
87
#include "runtime/threadStatisticalInfo.hpp"
88
#include "runtime/threadWXSetters.inline.hpp"
89
#include "runtime/timer.hpp"
90
#include "runtime/timerTrace.hpp"
91
#include "runtime/vframe.inline.hpp"
92
#include "runtime/vframeArray.hpp"
93
#include "runtime/vframe_hp.hpp"
94
#include "runtime/vmThread.hpp"
95
#include "runtime/vmOperations.hpp"
96
#include "services/threadService.hpp"
97
#include "utilities/copy.hpp"
98
#include "utilities/defaultStream.hpp"
99
#include "utilities/dtrace.hpp"
100
#include "utilities/events.hpp"
101
#include "utilities/macros.hpp"
102
#include "utilities/preserveException.hpp"
103
#include "utilities/spinYield.hpp"
104
#include "utilities/vmError.hpp"
106
#include "jvmci/jvmci.hpp"
107
#include "jvmci/jvmciEnv.hpp"
110
#include "jfr/jfr.hpp"
114
size_t JavaThread::_stack_size_at_create = 0;
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// Only bother with this argument setup if dtrace is available
120
#define HOTSPOT_THREAD_PROBE_start HOTSPOT_THREAD_START
121
#define HOTSPOT_THREAD_PROBE_stop HOTSPOT_THREAD_STOP
123
#define DTRACE_THREAD_PROBE(probe, javathread) \
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ResourceMark rm(this); \
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const char* name = (javathread)->name(); \
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len = strlen(name); \
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HOTSPOT_THREAD_PROBE_##probe(/* probe = start, stop */ \
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(char *) name, len, \
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java_lang_Thread::thread_id((javathread)->threadObj()), \
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(uintptr_t) (javathread)->osthread()->thread_id(), \
133
java_lang_Thread::is_daemon((javathread)->threadObj())); \
136
#else // ndef DTRACE_ENABLED
138
#define DTRACE_THREAD_PROBE(probe, javathread)
140
#endif // ndef DTRACE_ENABLED
142
void JavaThread::smr_delete() {143
if (_on_thread_list) {144
ThreadsSMRSupport::smr_delete(this);
150
// Initialized by VMThread at vm_global_init
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OopStorage* JavaThread::_thread_oop_storage = nullptr;
153
OopStorage* JavaThread::thread_oop_storage() {154
assert(_thread_oop_storage != nullptr, "not yet initialized");
155
return _thread_oop_storage;
158
void JavaThread::set_threadOopHandles(oop p) {159
assert(_thread_oop_storage != nullptr, "not yet initialized");
160
_threadObj = OopHandle(_thread_oop_storage, p);
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_vthread = OopHandle(_thread_oop_storage, p);
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_jvmti_vthread = OopHandle(_thread_oop_storage, p->is_a(vmClasses::BoundVirtualThread_klass()) ? p : nullptr);
163
_scopedValueCache = OopHandle(_thread_oop_storage, nullptr);
166
oop JavaThread::threadObj() const {167
// Ideally we would verify the current thread is oop_safe when this is called, but as we can
168
// be called from a signal handler we would have to use Thread::current_or_null_safe(). That
169
// has overhead and also interacts poorly with GetLastError on Windows due to the use of TLS.
170
// Instead callers must verify oop safe access.
171
return _threadObj.resolve();
174
oop JavaThread::vthread() const {175
return _vthread.resolve();
178
void JavaThread::set_vthread(oop p) {179
assert(_thread_oop_storage != nullptr, "not yet initialized");
183
oop JavaThread::jvmti_vthread() const {184
return _jvmti_vthread.resolve();
187
void JavaThread::set_jvmti_vthread(oop p) {188
assert(_thread_oop_storage != nullptr, "not yet initialized");
189
_jvmti_vthread.replace(p);
192
// If there is a virtual thread mounted then return vthread() oop.
193
// Otherwise, return threadObj().
194
oop JavaThread::vthread_or_thread() const {195
oop result = vthread();
196
if (result == nullptr) {197
result = threadObj();
202
oop JavaThread::scopedValueCache() const {203
return _scopedValueCache.resolve();
206
void JavaThread::set_scopedValueCache(oop p) {207
if (!_scopedValueCache.is_empty()) { // i.e. if the OopHandle has been allocated208
_scopedValueCache.replace(p);
210
assert(p == nullptr, "not yet initialized");
214
void JavaThread::clear_scopedValueBindings() {215
set_scopedValueCache(nullptr);
216
oop vthread_oop = vthread();
217
// vthread may be null here if we get a VM error during startup,
218
// before the java.lang.Thread instance has been created.
219
if (vthread_oop != nullptr) {220
java_lang_Thread::clear_scopedValueBindings(vthread_oop);
224
void JavaThread::allocate_threadObj(Handle thread_group, const char* thread_name,
225
bool daemon, TRAPS) {226
assert(thread_group.not_null(), "thread group should be specified");
227
assert(threadObj() == nullptr, "should only create Java thread object once");
229
InstanceKlass* ik = vmClasses::Thread_klass();
230
assert(ik->is_initialized(), "must be");
231
instanceHandle thread_oop = ik->allocate_instance_handle(CHECK);
233
// We are called from jni_AttachCurrentThread/jni_AttachCurrentThreadAsDaemon.
234
// We cannot use JavaCalls::construct_new_instance because the java.lang.Thread
235
// constructor calls Thread.current(), which must be set here.
236
java_lang_Thread::set_thread(thread_oop(), this);
237
set_threadOopHandles(thread_oop());
239
JavaValue result(T_VOID);
240
if (thread_name != nullptr) {241
Handle name = java_lang_String::create_from_str(thread_name, CHECK);
242
// Thread gets assigned specified name and null target
243
JavaCalls::call_special(&result,
246
vmSymbols::object_initializer_name(),
247
vmSymbols::threadgroup_string_void_signature(),
252
// Thread gets assigned name "Thread-nnn" and null target
253
// (java.lang.Thread doesn't have a constructor taking only a ThreadGroup argument)
254
JavaCalls::call_special(&result,
257
vmSymbols::object_initializer_name(),
258
vmSymbols::threadgroup_runnable_void_signature(),
263
os::set_priority(this, NormPriority);
266
java_lang_Thread::set_daemon(thread_oop());
270
// ======= JavaThread ========
274
jlong* JavaThread::_jvmci_old_thread_counters;
276
static bool jvmci_counters_include(JavaThread* thread) {277
return !JVMCICountersExcludeCompiler || !thread->is_Compiler_thread();
280
void JavaThread::collect_counters(jlong* array, int length) {281
assert(length == JVMCICounterSize, "wrong value");
282
for (int i = 0; i < length; i++) {283
array[i] = _jvmci_old_thread_counters[i];
285
for (JavaThread* tp : ThreadsListHandle()) {286
if (jvmci_counters_include(tp)) {287
for (int i = 0; i < length; i++) {288
array[i] += tp->_jvmci_counters[i];
294
// Attempt to enlarge the array for per thread counters.
295
static jlong* resize_counters_array(jlong* old_counters, int current_size, int new_size) {296
jlong* new_counters = NEW_C_HEAP_ARRAY_RETURN_NULL(jlong, new_size, mtJVMCI);
297
if (new_counters == nullptr) {300
if (old_counters == nullptr) {301
old_counters = new_counters;
302
memset(old_counters, 0, sizeof(jlong) * new_size);
304
for (int i = 0; i < MIN2((int) current_size, new_size); i++) {305
new_counters[i] = old_counters[i];
307
if (new_size > current_size) {308
memset(new_counters + current_size, 0, sizeof(jlong) * (new_size - current_size));
310
FREE_C_HEAP_ARRAY(jlong, old_counters);
315
// Attempt to enlarge the array for per thread counters.
316
bool JavaThread::resize_counters(int current_size, int new_size) {317
jlong* new_counters = resize_counters_array(_jvmci_counters, current_size, new_size);
318
if (new_counters == nullptr) {321
_jvmci_counters = new_counters;
326
class VM_JVMCIResizeCounters : public VM_Operation {332
VM_JVMCIResizeCounters(int new_size) : _new_size(new_size), _failed(false) { }333
VMOp_Type type() const { return VMOp_JVMCIResizeCounters; }334
bool allow_nested_vm_operations() const { return true; }336
// Resize the old thread counters array
337
jlong* new_counters = resize_counters_array(JavaThread::_jvmci_old_thread_counters, JVMCICounterSize, _new_size);
338
if (new_counters == nullptr) {342
JavaThread::_jvmci_old_thread_counters = new_counters;
345
// Now resize each threads array
346
for (JavaThread* tp : ThreadsListHandle()) {347
if (!tp->resize_counters(JVMCICounterSize, _new_size)) {353
JVMCICounterSize = _new_size;
357
bool failed() { return _failed; }360
bool JavaThread::resize_all_jvmci_counters(int new_size) {361
VM_JVMCIResizeCounters op(new_size);
362
VMThread::execute(&op);
366
#endif // INCLUDE_JVMCI
369
// Checks safepoint allowed and clears unhandled oops at potential safepoints.
370
void JavaThread::check_possible_safepoint() {371
if (_no_safepoint_count > 0) {373
assert(false, "Possible safepoint reached by thread that does not allow it");
375
#ifdef CHECK_UNHANDLED_OOPS
376
// Clear unhandled oops in JavaThreads so we get a crash right away.
377
clear_unhandled_oops();
378
#endif // CHECK_UNHANDLED_OOPS
380
// Macos/aarch64 should be in the right state for safepoint (e.g.
381
// deoptimization needs WXWrite). Crashes caused by the wrong state rarely
382
// happens in practice, making such issues hard to find and reproduce.
383
#if defined(__APPLE__) && defined(AARCH64)
384
if (AssertWXAtThreadSync) {385
assert_wx_state(WXWrite);
390
void JavaThread::check_for_valid_safepoint_state() {391
// Don't complain if running a debugging command.
392
if (DebuggingContext::is_enabled()) return;
394
// Check NoSafepointVerifier, which is implied by locks taken that can be
395
// shared with the VM thread. This makes sure that no locks with allow_vm_block
397
check_possible_safepoint();
399
if (thread_state() != _thread_in_vm) {400
fatal("LEAF method calling lock?");403
if (GCALotAtAllSafepoints) {404
// We could enter a safepoint here and thus have a gc
405
InterfaceSupport::check_gc_alot();
410
// A JavaThread is a normal Java thread
412
JavaThread::JavaThread(MEMFLAGS flags) :
415
_on_thread_list(false),
416
DEBUG_ONLY(_java_call_counter(0) COMMA)
417
_entry_point(nullptr),
418
_deopt_mark(nullptr),
419
_deopt_nmethod(nullptr),
420
_vframe_array_head(nullptr),
421
_vframe_array_last(nullptr),
422
_jvmti_deferred_updates(nullptr),
423
_callee_target(nullptr),
425
_vm_result_2(nullptr),
427
_current_pending_monitor(nullptr),
428
_current_pending_monitor_is_from_java(true),
429
_current_waiting_monitor(nullptr),
430
_active_handles(nullptr),
431
_free_handle_block(nullptr),
435
_thread_state(_thread_new),
436
_saved_exception_pc(nullptr),
438
_no_safepoint_count(0),
439
_visited_for_critical_count(false),
442
_terminated(_not_terminated),
443
_in_deopt_handler(0),
444
_doing_unsafe_access(false),
445
_do_not_unlock_if_synchronized(false),
447
_carrier_thread_suspended(false),
448
_is_in_VTMS_transition(false),
449
_is_in_tmp_VTMS_transition(false),
450
_is_disable_suspend(false),
451
_VTMS_transition_mark(false),
453
_is_VTMS_transition_disabler(false),
456
_jni_attach_state(_not_attaching_via_jni),
457
_is_in_internal_oome_mark(false),
459
_pending_deoptimization(-1),
460
_pending_monitorenter(false),
461
_pending_transfer_to_interpreter(false),
462
_pending_failed_speculation(0),
464
_libjvmci_runtime(nullptr),
465
_jvmci_counters(nullptr),
468
_jvmci_reserved_oop0(nullptr),
469
_live_nmethod(nullptr),
470
#endif // INCLUDE_JVMCI
472
_exception_oop(oop()),
473
_exception_pc(nullptr),
474
_exception_handler_pc(nullptr),
475
_is_method_handle_return(0),
477
_jni_active_critical(0),
478
_pending_jni_exception_check_fn(nullptr),
479
_depth_first_number(0),
481
// JVMTI PopFrame support
482
_popframe_condition(popframe_inactive),
483
_frames_to_pop_failed_realloc(0),
485
_cont_entry(nullptr),
486
_cont_fastpath(nullptr),
487
_cont_fastpath_thread_state(1),
488
_held_monitor_count(0),
489
_jni_monitor_count(0),
493
_popframe_preserved_args(nullptr),
494
_popframe_preserved_args_size(0),
496
_jvmti_thread_state(nullptr),
497
_interp_only_mode(0),
498
_should_post_on_exceptions_flag(JNI_FALSE),
499
_thread_stat(new ThreadStatistics()),
503
_class_to_be_initialized(nullptr),
505
_SleepEvent(ParkEvent::Allocate(this)),
508
set_jni_functions(jni_functions());
511
assert(_jvmci._implicit_exception_pc == nullptr, "must be");
512
if (JVMCICounterSize > 0) {513
resize_counters(0, (int) JVMCICounterSize);
515
#endif // INCLUDE_JVMCI
517
// Setup safepoint state info for this thread
518
ThreadSafepointState::create(this);
520
SafepointMechanism::initialize_header(this);
522
set_requires_cross_modify_fence(false);
525
assert(deferred_card_mark().is_empty(), "Default MemRegion ctor");
528
JavaThread* JavaThread::create_attaching_thread() {529
JavaThread* jt = new JavaThread();
530
jt->_jni_attach_state = _attaching_via_jni;
536
void JavaThread::interrupt() {537
// All callers should have 'this' thread protected by a
538
// ThreadsListHandle so that it cannot terminate and deallocate
540
debug_only(check_for_dangling_thread_pointer(this);)
542
// For Windows _interrupt_event
543
WINDOWS_ONLY(osthread()->set_interrupted(true);)
546
_SleepEvent->unpark();
548
// For JSR166 LockSupport.park
551
// For ObjectMonitor and JvmtiRawMonitor
552
_ParkEvent->unpark();
555
bool JavaThread::is_interrupted(bool clear_interrupted) {556
debug_only(check_for_dangling_thread_pointer(this);)
558
if (_threadObj.peek() == nullptr) {559
// If there is no j.l.Thread then it is impossible to have
560
// been interrupted. We can find null during VM initialization
561
// or when a JNI thread is still in the process of attaching.
562
// In such cases this must be the current thread.
563
assert(this == Thread::current(), "invariant");
567
bool interrupted = java_lang_Thread::interrupted(threadObj());
569
// NOTE that since there is no "lock" around the interrupt and
570
// is_interrupted operations, there is the possibility that the
571
// interrupted flag will be "false" but that the
572
// low-level events will be in the signaled state. This is
573
// intentional. The effect of this is that Object.wait() and
574
// LockSupport.park() will appear to have a spurious wakeup, which
575
// is allowed and not harmful, and the possibility is so rare that
576
// it is not worth the added complexity to add yet another lock.
577
// For the sleep event an explicit reset is performed on entry
578
// to JavaThread::sleep, so there is no early return. It has also been
579
// recommended not to put the interrupted flag into the "event"
580
// structure because it hides the issue.
581
// Also, because there is no lock, we must only clear the interrupt
582
// state if we are going to report that we were interrupted; otherwise
583
// an interrupt that happens just after we read the field would be lost.
584
if (interrupted && clear_interrupted) {585
assert(this == Thread::current(), "only the current thread can clear");
586
java_lang_Thread::set_interrupted(threadObj(), false);
587
WINDOWS_ONLY(osthread()->set_interrupted(false);)
592
// This is only for use by JVMTI RawMonitorWait. It emulates the actions of
593
// the Java code in Object::wait which are not present in RawMonitorWait.
594
bool JavaThread::get_and_clear_interrupted() {595
if (!is_interrupted(false)) {598
oop thread_oop = vthread_or_thread();
599
bool is_virtual = java_lang_VirtualThread::is_instance(thread_oop);
602
return is_interrupted(true);
604
// Virtual thread: clear interrupt status for both virtual and
605
// carrier threads under the interruptLock protection.
606
JavaThread* current = JavaThread::current();
607
HandleMark hm(current);
608
Handle thread_h(current, thread_oop);
609
ObjectLocker lock(Handle(current, java_lang_Thread::interrupt_lock(thread_h())), current);
611
// re-check the interrupt status under the interruptLock protection
612
bool interrupted = java_lang_Thread::interrupted(thread_h());
615
assert(this == Thread::current(), "only the current thread can clear");
616
java_lang_Thread::set_interrupted(thread_h(), false); // clear for virtual
617
java_lang_Thread::set_interrupted(threadObj(), false); // clear for carrier
618
WINDOWS_ONLY(osthread()->set_interrupted(false);)
623
void JavaThread::block_if_vm_exited() {624
if (_terminated == _vm_exited) {625
// _vm_exited is set at safepoint, and Threads_lock is never released
626
// so we will block here forever.
627
// Here we can be doing a jump from a safe state to an unsafe state without
628
// proper transition, but it happens after the final safepoint has begun so
629
// this jump won't cause any safepoint problems.
630
set_thread_state(_thread_in_vm);
631
Threads_lock->lock();
632
ShouldNotReachHere();
636
JavaThread::JavaThread(ThreadFunction entry_point, size_t stack_sz, MEMFLAGS flags) : JavaThread(flags) {637
set_entry_point(entry_point);
638
// Create the native thread itself.
640
os::ThreadType thr_type = os::java_thread;
641
thr_type = entry_point == &CompilerThread::thread_entry ? os::compiler_thread :
643
os::create_thread(this, thr_type, stack_sz);
644
// The _osthread may be null here because we ran out of memory (too many threads active).
645
// We need to throw and OutOfMemoryError - however we cannot do this here because the caller
646
// may hold a lock and all locks must be unlocked before throwing the exception (throwing
647
// the exception consists of creating the exception object & initializing it, initialization
648
// will leave the VM via a JavaCall and then all locks must be unlocked).
650
// The thread is still suspended when we reach here. Thread must be explicit started
651
// by creator! Furthermore, the thread must also explicitly be added to the Threads list
652
// by calling Threads:add. The reason why this is not done here, is because the thread
653
// object must be fully initialized (take a look at JVM_Start)
656
JavaThread::~JavaThread() {658
// Enqueue OopHandles for release by the service thread.
659
add_oop_handles_for_release();
661
// Return the sleep event to the free list
662
ParkEvent::Release(_SleepEvent);
663
_SleepEvent = nullptr;
665
// Free any remaining previous UnrollBlock
666
vframeArray* old_array = vframe_array_last();
668
if (old_array != nullptr) {669
Deoptimization::UnrollBlock* old_info = old_array->unroll_block();
670
old_array->set_unroll_block(nullptr);
675
JvmtiDeferredUpdates* updates = deferred_updates();
676
if (updates != nullptr) {677
// This can only happen if thread is destroyed before deoptimization occurs.
678
assert(updates->count() > 0, "Updates holder not deleted");
679
// free deferred updates.
681
set_deferred_updates(nullptr);
684
// All Java related clean up happens in exit
685
ThreadSafepointState::destroy(this);
686
if (_thread_stat != nullptr) delete _thread_stat;
689
if (JVMCICounterSize > 0) {690
FREE_C_HEAP_ARRAY(jlong, _jvmci_counters);
692
#endif // INCLUDE_JVMCI
696
// First JavaThread specific code executed by a new Java thread.
697
void JavaThread::pre_run() {698
// empty - see comments in run()
701
// The main routine called by a new Java thread. This isn't overridden
702
// by subclasses, instead different subclasses define a different "entry_point"
703
// which defines the actual logic for that kind of thread.
704
void JavaThread::run() {705
// initialize thread-local alloc buffer related fields
708
_stack_overflow_state.create_stack_guard_pages();
710
cache_global_variables();
712
// Thread is now sufficiently initialized to be handled by the safepoint code as being
713
// in the VM. Change thread state from _thread_new to _thread_in_vm
714
assert(this->thread_state() == _thread_new, "wrong thread state");
715
set_thread_state(_thread_in_vm);
717
// Before a thread is on the threads list it is always safe, so after leaving the
718
// _thread_new we should emit a instruction barrier. The distance to modified code
719
// from here is probably far enough, but this is consistent and safe.
720
OrderAccess::cross_modify_fence();
722
assert(JavaThread::current() == this, "sanity check");
723
assert(!Thread::current()->owns_locks(), "sanity check");
725
DTRACE_THREAD_PROBE(start, this);
727
// This operation might block. We call that after all safepoint checks for a new thread has
729
set_active_handles(JNIHandleBlock::allocate_block());
731
if (JvmtiExport::should_post_thread_life()) {732
JvmtiExport::post_thread_start(this);
736
if (AlwaysPreTouchStacks) {740
// We call another function to do the rest so we are sure that the stack addresses used
741
// from there will be lower than the stack base just computed.
745
void JavaThread::thread_main_inner() {746
assert(JavaThread::current() == this, "sanity check");
747
assert(_threadObj.peek() != nullptr, "just checking");
749
// Execute thread entry point unless this thread has a pending exception.
750
// Note: Due to JVMTI StopThread we can have pending exceptions already!
751
if (!this->has_pending_exception()) {753
ResourceMark rm(this);
754
this->set_native_thread_name(this->name());
757
this->entry_point()(this, this);
760
DTRACE_THREAD_PROBE(stop, this);
762
// Cleanup is handled in post_run()
765
// Shared teardown for all JavaThreads
766
void JavaThread::post_run() {768
this->unregister_thread_stack_with_NMT();
769
// Defer deletion to here to ensure 'this' is still referenceable in call_run
770
// for any shared tear-down.
774
static void ensure_join(JavaThread* thread) {775
// We do not need to grab the Threads_lock, since we are operating on ourself.
776
Handle threadObj(thread, thread->threadObj());
777
assert(threadObj.not_null(), "java thread object must exist");
778
ObjectLocker lock(threadObj, thread);
779
// Thread is exiting. So set thread_status field in java.lang.Thread class to TERMINATED.
780
java_lang_Thread::set_thread_status(threadObj(), JavaThreadStatus::TERMINATED);
781
// Clear the native thread instance - this makes isAlive return false and allows the join()
782
// to complete once we've done the notify_all below. Needs a release() to obey Java Memory Model
784
assert(java_lang_Thread::thread(threadObj()) == thread, "must be alive");
785
java_lang_Thread::release_set_thread(threadObj(), nullptr);
786
lock.notify_all(thread);
787
// Ignore pending exception, since we are exiting anyway
788
thread->clear_pending_exception();
791
static bool is_daemon(oop threadObj) {792
return (threadObj != nullptr && java_lang_Thread::is_daemon(threadObj));
795
// For any new cleanup additions, please check to see if they need to be applied to
796
// cleanup_failed_attach_current_thread as well.
797
void JavaThread::exit(bool destroy_vm, ExitType exit_type) {798
assert(this == JavaThread::current(), "thread consistency check");
799
assert(!is_exiting(), "should not be exiting or terminated already");
801
elapsedTimer _timer_exit_phase1;
802
elapsedTimer _timer_exit_phase2;
803
elapsedTimer _timer_exit_phase3;
804
elapsedTimer _timer_exit_phase4;
806
if (log_is_enabled(Debug, os, thread, timer)) {807
_timer_exit_phase1.start();
811
Handle uncaught_exception(this, this->pending_exception());
812
this->clear_pending_exception();
813
Handle threadObj(this, this->threadObj());
814
assert(threadObj.not_null(), "Java thread object should be created");
817
if (uncaught_exception.not_null()) {819
// Call method Thread.dispatchUncaughtException().
820
Klass* thread_klass = vmClasses::Thread_klass();
821
JavaValue result(T_VOID);
822
JavaCalls::call_virtual(&result,
823
threadObj, thread_klass,
824
vmSymbols::dispatchUncaughtException_name(),
825
vmSymbols::throwable_void_signature(),
828
if (HAS_PENDING_EXCEPTION) {829
ResourceMark rm(this);
830
jio_fprintf(defaultStream::error_stream(),
831
"\nException: %s thrown from the UncaughtExceptionHandler"
832
" in thread \"%s\"\n",
833
pending_exception()->klass()->external_name(),
835
CLEAR_PENDING_EXCEPTION;
839
if (!is_Compiler_thread()) {840
// We have finished executing user-defined Java code and now have to do the
841
// implementation specific clean-up by calling Thread.exit(). We prevent any
842
// asynchronous exceptions from being delivered while in Thread.exit()
843
// to ensure the clean-up is not corrupted.
844
NoAsyncExceptionDeliveryMark _no_async(this);
847
JavaValue result(T_VOID);
848
Klass* thread_klass = vmClasses::Thread_klass();
849
JavaCalls::call_virtual(&result,
850
threadObj, thread_klass,
851
vmSymbols::exit_method_name(),
852
vmSymbols::void_method_signature(),
854
CLEAR_PENDING_EXCEPTION;
858
if (JvmtiExport::should_post_thread_life()) {859
JvmtiExport::post_thread_end(this);
862
// before_exit() has already posted JVMTI THREAD_END events
865
// Cleanup any pending async exception now since we cannot access oops after
866
// BarrierSet::barrier_set()->on_thread_detach() has been executed.
867
if (has_async_exception_condition()) {868
handshake_state()->clean_async_exception_operation();
871
// The careful dance between thread suspension and exit is handled here.
872
// Since we are in thread_in_vm state and suspension is done with handshakes,
873
// we can just put in the exiting state and it will be correctly handled.
874
// Also, no more async exceptions will be added to the queue after this point.
875
set_terminated(_thread_exiting);
876
ThreadService::current_thread_exiting(this, is_daemon(threadObj()));
878
if (log_is_enabled(Debug, os, thread, timer)) {879
_timer_exit_phase1.stop();
880
_timer_exit_phase2.start();
883
// Capture daemon status before the thread is marked as terminated.
884
bool daemon = is_daemon(threadObj());
886
// Notify waiters on thread object. This has to be done after exit() is called
887
// on the thread (if the thread is the last thread in a daemon ThreadGroup the
888
// group should have the destroyed bit set before waiters are notified).
890
assert(!this->has_pending_exception(), "ensure_join should have cleared");
892
if (log_is_enabled(Debug, os, thread, timer)) {893
_timer_exit_phase2.stop();
894
_timer_exit_phase3.start();
896
// 6282335 JNI DetachCurrentThread spec states that all Java monitors
897
// held by this thread must be released. The spec does not distinguish
898
// between JNI-acquired and regular Java monitors. We can only see
899
// regular Java monitors here if monitor enter-exit matching is broken.
901
// ensure_join() ignores IllegalThreadStateExceptions, and so does
902
// ObjectSynchronizer::release_monitors_owned_by_thread().
903
if (exit_type == jni_detach) {904
// Sanity check even though JNI DetachCurrentThread() would have
905
// returned JNI_ERR if there was a Java frame. JavaThread exit
906
// should be done executing Java code by the time we get here.
907
assert(!this->has_last_Java_frame(),
908
"should not have a Java frame when detaching or exiting");
909
ObjectSynchronizer::release_monitors_owned_by_thread(this);
910
assert(!this->has_pending_exception(), "release_monitors should have cleared");
911
// Check for monitor counts being out of sync.
912
assert(held_monitor_count() == jni_monitor_count(),
913
"held monitor count should be equal to jni: " INTX_FORMAT " != " INTX_FORMAT,
914
held_monitor_count(), jni_monitor_count());
915
// All in-use monitors, including JNI-locked ones, should have been released above.
916
assert(held_monitor_count() == 0, "Failed to unlock " INTX_FORMAT " object monitors",
917
held_monitor_count());
919
// Check for monitor counts being out of sync.
920
assert(held_monitor_count() == jni_monitor_count(),
921
"held monitor count should be equal to jni: " INTX_FORMAT " != " INTX_FORMAT,
922
held_monitor_count(), jni_monitor_count());
923
// It is possible that a terminating thread failed to unlock monitors it locked
924
// via JNI so we don't assert the count is zero.
927
if (CheckJNICalls && jni_monitor_count() > 0) {928
// We would like a fatal here, but due to we never checked this before there
929
// is a lot of tests which breaks, even with an error log.
930
log_debug(jni)("JavaThread %s (tid: " UINTX_FORMAT ") with Objects still locked by JNI MonitorEnter.",931
exit_type == JavaThread::normal_exit ? "exiting" : "detaching", os::current_thread_id());
934
// These things needs to be done while we are still a Java Thread. Make sure that thread
935
// is in a consistent state, in case GC happens
936
JFR_ONLY(Jfr::on_thread_exit(this);)
938
if (active_handles() != nullptr) {939
JNIHandleBlock* block = active_handles();
940
set_active_handles(nullptr);
941
JNIHandleBlock::release_block(block);
944
if (free_handle_block() != nullptr) {945
JNIHandleBlock* block = free_handle_block();
946
set_free_handle_block(nullptr);
947
JNIHandleBlock::release_block(block);
950
// These have to be removed while this is still a valid thread.
951
_stack_overflow_state.remove_stack_guard_pages();
957
if (JvmtiEnv::environments_might_exist()) {958
JvmtiExport::cleanup_thread(this);
961
// We need to cache the thread name for logging purposes below as once
962
// we have called on_thread_detach this thread must not access any oops.
963
char* thread_name = nullptr;
964
if (log_is_enabled(Debug, os, thread, timer)) {965
ResourceMark rm(this);
966
thread_name = os::strdup(name());
969
if (log_is_enabled(Info, os, thread)) {970
ResourceMark rm(this);
971
log_info(os, thread)("JavaThread %s (name: \"%s\", tid: " UINTX_FORMAT ").",972
exit_type == JavaThread::normal_exit ? "exiting" : "detaching",
973
name(), os::current_thread_id());
976
if (log_is_enabled(Debug, os, thread, timer)) {977
_timer_exit_phase3.stop();
978
_timer_exit_phase4.start();
982
if (JVMCICounterSize > 0) {983
if (jvmci_counters_include(this)) {984
for (int i = 0; i < JVMCICounterSize; i++) {985
_jvmci_old_thread_counters[i] += _jvmci_counters[i];
989
#endif // INCLUDE_JVMCI
991
// Remove from list of active threads list, and notify VM thread if we are the last non-daemon thread.
992
// We call BarrierSet::barrier_set()->on_thread_detach() here so no touching of oops after this point.
993
Threads::remove(this, daemon);
995
if (log_is_enabled(Debug, os, thread, timer)) {996
_timer_exit_phase4.stop();
997
log_debug(os, thread, timer)("name='%s'"998
", exit-phase1=" JLONG_FORMAT
999
", exit-phase2=" JLONG_FORMAT
1000
", exit-phase3=" JLONG_FORMAT
1001
", exit-phase4=" JLONG_FORMAT,
1003
_timer_exit_phase1.milliseconds(),
1004
_timer_exit_phase2.milliseconds(),
1005
_timer_exit_phase3.milliseconds(),
1006
_timer_exit_phase4.milliseconds());
1007
os::free(thread_name);
1011
void JavaThread::cleanup_failed_attach_current_thread(bool is_daemon) {1012
if (active_handles() != nullptr) {1013
JNIHandleBlock* block = active_handles();
1014
set_active_handles(nullptr);
1015
JNIHandleBlock::release_block(block);
1018
if (free_handle_block() != nullptr) {1019
JNIHandleBlock* block = free_handle_block();
1020
set_free_handle_block(nullptr);
1021
JNIHandleBlock::release_block(block);
1024
// These have to be removed while this is still a valid thread.
1025
_stack_overflow_state.remove_stack_guard_pages();
1031
Threads::remove(this, is_daemon);
1035
JavaThread* JavaThread::active() {1036
Thread* thread = Thread::current();
1037
if (thread->is_Java_thread()) {1038
return JavaThread::cast(thread);
1040
assert(thread->is_VM_thread(), "this must be a vm thread");
1041
VM_Operation* op = ((VMThread*) thread)->vm_operation();
1042
JavaThread *ret = op == nullptr ? nullptr : JavaThread::cast(op->calling_thread());
1047
bool JavaThread::is_lock_owned(address adr) const {1048
assert(LockingMode != LM_LIGHTWEIGHT, "should not be called with new lightweight locking");
1049
return is_in_full_stack(adr);
1052
oop JavaThread::exception_oop() const {1053
return Atomic::load(&_exception_oop);
1056
void JavaThread::set_exception_oop(oop o) {1057
Atomic::store(&_exception_oop, o);
1060
void JavaThread::handle_special_runtime_exit_condition() {1061
if (is_obj_deopt_suspend()) {1062
frame_anchor()->make_walkable();
1063
wait_for_object_deoptimization();
1065
JFR_ONLY(SUSPEND_THREAD_CONDITIONAL(this);)
1069
// Asynchronous exceptions support
1071
void JavaThread::handle_async_exception(oop java_throwable) {1072
assert(java_throwable != nullptr, "should have an _async_exception to throw");
1073
assert(!is_at_poll_safepoint(), "should have never called this method");
1075
if (has_last_Java_frame()) {1076
frame f = last_frame();
1077
if (f.is_runtime_frame()) {1078
// If the topmost frame is a runtime stub, then we are calling into
1079
// OptoRuntime from compiled code. Some runtime stubs (new, monitor_exit..)
1080
// must deoptimize the caller before continuing, as the compiled exception
1081
// handler table may not be valid.
1082
RegisterMap reg_map(this,
1083
RegisterMap::UpdateMap::skip,
1084
RegisterMap::ProcessFrames::include,
1085
RegisterMap::WalkContinuation::skip);
1086
frame compiled_frame = f.sender(®_map);
1087
if (!StressCompiledExceptionHandlers && compiled_frame.can_be_deoptimized()) {1088
Deoptimization::deoptimize(this, compiled_frame);
1093
// We cannot call Exceptions::_throw(...) here because we cannot block
1094
set_pending_exception(java_throwable, __FILE__, __LINE__);
1096
clear_scopedValueBindings();
1098
LogTarget(Info, exceptions) lt;
1099
if (lt.is_enabled()) {1102
ls.print("Async. exception installed at runtime exit (" INTPTR_FORMAT ")", p2i(this));1103
if (has_last_Java_frame()) {1104
frame f = last_frame();
1105
ls.print(" (pc: " INTPTR_FORMAT " sp: " INTPTR_FORMAT " )", p2i(f.pc()), p2i(f.sp()));1107
ls.print_cr(" of type: %s", java_throwable->klass()->external_name());1111
void JavaThread::install_async_exception(AsyncExceptionHandshake* aeh) {1112
// Do not throw asynchronous exceptions against the compiler thread
1113
// or if the thread is already exiting.
1114
if (!can_call_java() || is_exiting()) {1119
oop exception = aeh->exception();
1120
Handshake::execute(aeh, this); // Install asynchronous handshake
1123
if (log_is_enabled(Info, exceptions)) {1124
log_info(exceptions)("Pending Async. exception installed of type: %s",1125
InstanceKlass::cast(exception->klass())->external_name());
1127
// for AbortVMOnException flag
1128
Exceptions::debug_check_abort(exception->klass()->external_name());
1130
oop vt_oop = vthread();
1131
if (vt_oop == nullptr || !vt_oop->is_a(vmClasses::BaseVirtualThread_klass())) {1132
// Interrupt thread so it will wake up from a potential wait()/sleep()/park()
1133
java_lang_Thread::set_interrupted(threadObj(), true);
1138
class InstallAsyncExceptionHandshake : public HandshakeClosure {1139
AsyncExceptionHandshake* _aeh;
1141
InstallAsyncExceptionHandshake(AsyncExceptionHandshake* aeh) :
1142
HandshakeClosure("InstallAsyncException"), _aeh(aeh) {}1143
~InstallAsyncExceptionHandshake() {1144
// If InstallAsyncExceptionHandshake was never executed we need to clean up _aeh.
1147
void do_thread(Thread* thr) {1148
JavaThread* target = JavaThread::cast(thr);
1149
target->install_async_exception(_aeh);
1154
void JavaThread::send_async_exception(JavaThread* target, oop java_throwable) {1155
OopHandle e(Universe::vm_global(), java_throwable);
1156
InstallAsyncExceptionHandshake iaeh(new AsyncExceptionHandshake(e));
1157
Handshake::execute(&iaeh, target);
1161
void JavaThread::set_is_in_VTMS_transition(bool val) {1162
_is_in_VTMS_transition = val;
1166
void JavaThread::set_is_VTMS_transition_disabler(bool val) {1167
_is_VTMS_transition_disabler = val;
1172
// External suspension mechanism.
1174
// Guarantees on return (for a valid target thread):
1175
// - Target thread will not execute any new bytecode.
1176
// - Target thread will not enter any new monitors.
1178
bool JavaThread::java_suspend() {1180
// Suspending a JavaThread in VTMS transition or disabling VTMS transitions can cause deadlocks.
1181
assert(!is_in_VTMS_transition(), "no suspend allowed in VTMS transition");
1182
assert(!is_VTMS_transition_disabler(), "no suspend allowed for VTMS transition disablers");
1185
guarantee(Thread::is_JavaThread_protected(/* target */ this),
1186
"target JavaThread is not protected in calling context.");
1187
return this->handshake_state()->suspend();
1190
bool JavaThread::java_resume() {1191
guarantee(Thread::is_JavaThread_protected_by_TLH(/* target */ this),
1192
"missing ThreadsListHandle in calling context.");
1193
return this->handshake_state()->resume();
1196
// Wait for another thread to perform object reallocation and relocking on behalf of
1197
// this thread. The current thread is required to change to _thread_blocked in order
1198
// to be seen to be safepoint/handshake safe whilst suspended and only after becoming
1199
// handshake safe, the other thread can complete the handshake used to synchronize
1200
// with this thread and then perform the reallocation and relocking.
1201
// See EscapeBarrier::sync_and_suspend_*()
1203
void JavaThread::wait_for_object_deoptimization() {1204
assert(!has_last_Java_frame() || frame_anchor()->walkable(), "should have walkable stack");
1205
assert(this == Thread::current(), "invariant");
1207
bool spin_wait = os::is_MP();
1209
ThreadBlockInVM tbivm(this, true /* allow_suspend */);
1210
// Wait for object deoptimization if requested.
1212
// A single deoptimization is typically very short. Microbenchmarks
1213
// showed 5% better performance when spinning.
1214
const uint spin_limit = 10 * SpinYield::default_spin_limit;
1215
SpinYield spin(spin_limit);
1216
for (uint i = 0; is_obj_deopt_suspend() && i < spin_limit; i++) {1222
MonitorLocker ml(this, EscapeBarrier_lock, Monitor::_no_safepoint_check_flag);
1223
if (is_obj_deopt_suspend()) {1227
// A handshake for obj. deoptimization suspend could have been processed so
1228
// we must check after processing.
1229
} while (is_obj_deopt_suspend());
1233
// Verify the JavaThread has not yet been published in the Threads::list, and
1234
// hence doesn't need protection from concurrent access at this stage.
1235
void JavaThread::verify_not_published() {1236
// Cannot create a ThreadsListHandle here and check !tlh.includes(this)
1237
// since an unpublished JavaThread doesn't participate in the
1238
// Thread-SMR protocol for keeping a ThreadsList alive.
1239
assert(!on_thread_list(), "JavaThread shouldn't have been published yet!");
1243
// Slow path when the native==>Java barriers detect a safepoint/handshake is
1244
// pending, when _suspend_flags is non-zero or when we need to process a stack
1245
// watermark. Also check for pending async exceptions (except unsafe access error).
1246
// Note only the native==>Java barriers can call this function when thread state
1247
// is _thread_in_native_trans.
1248
void JavaThread::check_special_condition_for_native_trans(JavaThread *thread) {1249
assert(thread->thread_state() == _thread_in_native_trans, "wrong state");
1250
assert(!thread->has_last_Java_frame() || thread->frame_anchor()->walkable(), "Unwalkable stack in native->Java transition");
1252
thread->set_thread_state(_thread_in_vm);
1254
// Enable WXWrite: called directly from interpreter native wrapper.
1255
MACOS_AARCH64_ONLY(ThreadWXEnable wx(WXWrite, thread));
1257
SafepointMechanism::process_if_requested_with_exit_check(thread, true /* check asyncs */);
1259
// After returning from native, it could be that the stack frames are not
1260
// yet safe to use. We catch such situations in the subsequent stack watermark
1261
// barrier, which will trap unsafe stack frames.
1262
StackWatermarkSet::before_unwind(thread);
1267
// Function for testing deoptimization
1268
void JavaThread::deoptimize() {1269
StackFrameStream fst(this, false /* update */, true /* process_frames */);
1270
bool deopt = false; // Dump stack only if a deopt actually happens.
1271
bool only_at = strlen(DeoptimizeOnlyAt) > 0;
1272
// Iterate over all frames in the thread and deoptimize
1273
for (; !fst.is_done(); fst.next()) {1274
if (fst.current()->can_be_deoptimized()) {1277
// Deoptimize only at particular bcis. DeoptimizeOnlyAt
1278
// consists of comma or carriage return separated numbers so
1279
// search for the current bci in that string.
1280
address pc = fst.current()->pc();
1281
nmethod* nm = fst.current()->cb()->as_nmethod();
1282
ScopeDesc* sd = nm->scope_desc_at(pc);
1284
jio_snprintf(buffer, sizeof(buffer), "%d", sd->bci());
1285
size_t len = strlen(buffer);
1286
const char * found = strstr(DeoptimizeOnlyAt, buffer);
1287
while (found != nullptr) {1288
if ((found[len] == ',' || found[len] == '\n' || found[len] == '\0') &&
1289
(found == DeoptimizeOnlyAt || found[-1] == ',' || found[-1] == '\n')) {1290
// Check that the bci found is bracketed by terminators.
1293
found = strstr(found + 1, buffer);
1300
if (DebugDeoptimization && !deopt) {1301
deopt = true; // One-time only print before deopt
1302
tty->print_cr("[BEFORE Deoptimization]");1306
Deoptimization::deoptimize(this, *fst.current());
1310
if (DebugDeoptimization && deopt) {1311
tty->print_cr("[AFTER Deoptimization]");1318
void JavaThread::make_zombies() {1319
for (StackFrameStream fst(this, true /* update */, true /* process_frames */); !fst.is_done(); fst.next()) {1320
if (fst.current()->can_be_deoptimized()) {1321
// it is a Java nmethod
1322
nmethod* nm = CodeCache::find_nmethod(fst.current()->pc());
1323
assert(nm != nullptr, "did not find nmethod");
1324
nm->make_not_entrant();
1331
void JavaThread::deoptimize_marked_methods() {1332
if (!has_last_Java_frame()) return;
1333
StackFrameStream fst(this, false /* update */, true /* process_frames */);
1334
for (; !fst.is_done(); fst.next()) {1335
if (fst.current()->should_be_deoptimized()) {1336
Deoptimization::deoptimize(this, *fst.current());
1342
void JavaThread::verify_frame_info() {1343
assert((!has_last_Java_frame() && java_call_counter() == 0) ||
1344
(has_last_Java_frame() && java_call_counter() > 0),
1345
"unexpected frame info: has_last_frame=%s, java_call_counter=%d",
1346
has_last_Java_frame() ? "true" : "false", java_call_counter());
1350
// Push on a new block of JNI handles.
1351
void JavaThread::push_jni_handle_block() {1352
// Allocate a new block for JNI handles.
1353
// Inlined code from jni_PushLocalFrame()
1354
JNIHandleBlock* old_handles = active_handles();
1355
JNIHandleBlock* new_handles = JNIHandleBlock::allocate_block(this);
1356
assert(old_handles != nullptr && new_handles != nullptr, "should not be null");
1357
new_handles->set_pop_frame_link(old_handles); // make sure java handles get gc'd.
1358
set_active_handles(new_handles);
1361
// Pop off the current block of JNI handles.
1362
void JavaThread::pop_jni_handle_block() {1363
// Release our JNI handle block
1364
JNIHandleBlock* old_handles = active_handles();
1365
JNIHandleBlock* new_handles = old_handles->pop_frame_link();
1366
assert(new_handles != nullptr, "should never set active handles to null");
1367
set_active_handles(new_handles);
1368
old_handles->set_pop_frame_link(nullptr);
1369
JNIHandleBlock::release_block(old_handles, this);
1372
void JavaThread::oops_do_no_frames(OopClosure* f, NMethodClosure* cf) {1373
// Verify that the deferred card marks have been flushed.
1374
assert(deferred_card_mark().is_empty(), "Should be empty during GC");
1376
// Traverse the GCHandles
1377
Thread::oops_do_no_frames(f, cf);
1379
if (active_handles() != nullptr) {1380
active_handles()->oops_do(f);
1383
DEBUG_ONLY(verify_frame_info();)
1385
assert(vframe_array_head() == nullptr, "deopt in progress at a safepoint!");
1386
// If we have deferred set_locals there might be oops waiting to be
1388
GrowableArray<jvmtiDeferredLocalVariableSet*>* list = JvmtiDeferredUpdates::deferred_locals(this);
1389
if (list != nullptr) {1390
for (int i = 0; i < list->length(); i++) {1391
list->at(i)->oops_do(f);
1395
// Traverse instance variables at the end since the GC may be moving things
1396
// around using this function
1397
f->do_oop((oop*) &_vm_result);
1398
f->do_oop((oop*) &_exception_oop);
1400
f->do_oop((oop*) &_jvmci_reserved_oop0);
1402
if (_live_nmethod != nullptr && cf != nullptr) {1403
cf->do_nmethod(_live_nmethod);
1407
if (jvmti_thread_state() != nullptr) {1408
jvmti_thread_state()->oops_do(f, cf);
1411
// The continuation oops are really on the stack. But there is typically at most
1412
// one of those per thread, so we handle them here in the oops_do_no_frames part
1413
// so that we don't have to sprinkle as many stack watermark checks where these
1414
// oops are used. We just need to make sure the thread has started processing.
1415
ContinuationEntry* entry = _cont_entry;
1416
while (entry != nullptr) {1417
f->do_oop((oop*)entry->cont_addr());
1418
f->do_oop((oop*)entry->chunk_addr());
1419
entry = entry->parent();
1422
if (LockingMode == LM_LIGHTWEIGHT) {1423
lock_stack().oops_do(f);
1427
void JavaThread::oops_do_frames(OopClosure* f, NMethodClosure* cf) {1428
if (!has_last_Java_frame()) {1431
// Finish any pending lazy GC activity for the frames
1432
StackWatermarkSet::finish_processing(this, nullptr /* context */, StackWatermarkKind::gc);
1433
// Traverse the execution stack
1434
for (StackFrameStream fst(this, true /* update */, false /* process_frames */); !fst.is_done(); fst.next()) {1435
fst.current()->oops_do(f, cf, fst.register_map());
1440
void JavaThread::verify_states_for_handshake() {1441
// This checks that the thread has a correct frame state during a handshake.
1442
verify_frame_info();
1446
void JavaThread::nmethods_do(NMethodClosure* cf) {1447
DEBUG_ONLY(verify_frame_info();)
1448
MACOS_AARCH64_ONLY(ThreadWXEnable wx(WXWrite, Thread::current());)
1450
if (has_last_Java_frame()) {1451
// Traverse the execution stack
1452
for (StackFrameStream fst(this, true /* update */, true /* process_frames */); !fst.is_done(); fst.next()) {1453
fst.current()->nmethod_do(cf);
1457
if (jvmti_thread_state() != nullptr) {1458
jvmti_thread_state()->nmethods_do(cf);
1462
if (_live_nmethod != nullptr) {1463
cf->do_nmethod(_live_nmethod);
1468
void JavaThread::metadata_do(MetadataClosure* f) {1469
if (has_last_Java_frame()) {1470
// Traverse the execution stack to call f() on the methods in the stack
1471
for (StackFrameStream fst(this, true /* update */, true /* process_frames */); !fst.is_done(); fst.next()) {1472
fst.current()->metadata_do(f);
1474
} else if (is_Compiler_thread()) {1475
// need to walk ciMetadata in current compile tasks to keep alive.
1476
CompilerThread* ct = (CompilerThread*)this;
1477
if (ct->env() != nullptr) {1478
ct->env()->metadata_do(f);
1480
CompileTask* task = ct->task();
1481
if (task != nullptr) {1482
task->metadata_do(f);
1488
static const char* _get_thread_state_name(JavaThreadState _thread_state) {1489
switch (_thread_state) {1490
case _thread_uninitialized: return "_thread_uninitialized";
1491
case _thread_new: return "_thread_new";
1492
case _thread_new_trans: return "_thread_new_trans";
1493
case _thread_in_native: return "_thread_in_native";
1494
case _thread_in_native_trans: return "_thread_in_native_trans";
1495
case _thread_in_vm: return "_thread_in_vm";
1496
case _thread_in_vm_trans: return "_thread_in_vm_trans";
1497
case _thread_in_Java: return "_thread_in_Java";
1498
case _thread_in_Java_trans: return "_thread_in_Java_trans";
1499
case _thread_blocked: return "_thread_blocked";
1500
case _thread_blocked_trans: return "_thread_blocked_trans";
1501
default: return "unknown thread state";
1505
void JavaThread::print_thread_state_on(outputStream *st) const {1506
st->print_cr(" JavaThread state: %s", _get_thread_state_name(_thread_state));1509
// Called by Threads::print() for VM_PrintThreads operation
1510
void JavaThread::print_on(outputStream *st, bool print_extended_info) const {1511
st->print_raw("\"");1512
st->print_raw(name());
1513
st->print_raw("\" ");1514
oop thread_oop = threadObj();
1515
if (thread_oop != nullptr) {1516
st->print("#" INT64_FORMAT " [%ld] ", (int64_t)java_lang_Thread::thread_id(thread_oop), (long) osthread()->thread_id());1517
if (java_lang_Thread::is_daemon(thread_oop)) st->print("daemon ");1518
st->print("prio=%d ", java_lang_Thread::priority(thread_oop));1520
Thread::print_on(st, print_extended_info);
1521
// print guess for valid stack memory region (assume 4K pages); helps lock debugging
1522
st->print_cr("[" INTPTR_FORMAT "]", (intptr_t)last_Java_sp() & ~right_n_bits(12));1523
if (thread_oop != nullptr) {1524
if (is_vthread_mounted()) {1526
assert(vt != nullptr, "");
1527
st->print_cr(" Carrying virtual thread #" INT64_FORMAT, (int64_t)java_lang_Thread::thread_id(vt));1529
st->print_cr(" java.lang.Thread.State: %s", java_lang_Thread::thread_status_name(thread_oop));1533
_safepoint_state->print_on(st);
1535
if (is_Compiler_thread()) {1536
CompileTask *task = ((CompilerThread*)this)->task();
1537
if (task != nullptr) {1538
st->print(" Compiling: ");1539
task->print(st, nullptr, true, false);
1541
st->print(" No compile task");1547
void JavaThread::print() const { print_on(tty); }1549
void JavaThread::print_name_on_error(outputStream* st, char *buf, int buflen) const {1550
st->print("%s", get_thread_name_string(buf, buflen));1553
// Called by fatal error handler. The difference between this and
1554
// JavaThread::print() is that we can't grab lock or allocate memory.
1555
void JavaThread::print_on_error(outputStream* st, char *buf, int buflen) const {1556
st->print("%s \"%s\"", type_name(), get_thread_name_string(buf, buflen));1557
Thread* current = Thread::current_or_null_safe();
1558
assert(current != nullptr, "cannot be called by a detached thread");
1560
if (!current->is_Java_thread() || JavaThread::cast(current)->is_oop_safe()) {1561
// Only access threadObj() if current thread is not a JavaThread
1562
// or if it is a JavaThread that can safely access oops.
1563
oop thread_obj = threadObj();
1564
if (thread_obj != nullptr) {1565
st->print(java_lang_Thread::is_daemon(thread_obj) ? " daemon" : " ");
1569
st->print("%s", _get_thread_state_name(_thread_state));1571
st->print(", id=%d", osthread()->thread_id());1573
// Use raw field members for stack base/size as this could be
1574
// called before a thread has run enough to initialize them.
1575
st->print(", stack(" PTR_FORMAT "," PTR_FORMAT ") (" PROPERFMT ")",1576
p2i(_stack_base - _stack_size), p2i(_stack_base),
1577
PROPERFMTARGS(_stack_size));
1580
ThreadsSMRSupport::print_info_on(this, st);
1587
void JavaThread::frames_do(void f(frame*, const RegisterMap* map)) {1588
// ignore if there is no stack
1589
if (!has_last_Java_frame()) return;
1590
// traverse the stack frames. Starts from top frame.
1591
for (StackFrameStream fst(this, true /* update_map */, true /* process_frames */, false /* walk_cont */); !fst.is_done(); fst.next()) {1592
frame* fr = fst.current();
1593
f(fr, fst.register_map());
1597
static void frame_verify(frame* f, const RegisterMap *map) { f->verify(map); }1599
void JavaThread::verify() {1600
// Verify oops in the thread.
1601
oops_do(&VerifyOopClosure::verify_oop, nullptr);
1603
// Verify the stack frames.
1604
frames_do(frame_verify);
1607
// CR 6300358 (sub-CR 2137150)
1608
// Most callers of this method assume that it can't return null but a
1609
// thread may not have a name whilst it is in the process of attaching to
1610
// the VM - see CR 6412693, and there are places where a JavaThread can be
1611
// seen prior to having its threadObj set (e.g., JNI attaching threads and
1612
// if vm exit occurs during initialization). These cases can all be accounted
1613
// for such that this method never returns null.
1614
const char* JavaThread::name() const {1615
if (Thread::is_JavaThread_protected(/* target */ this)) {1616
// The target JavaThread is protected so get_thread_name_string() is safe:
1617
return get_thread_name_string();
1620
// The target JavaThread is not protected so we return the default:
1621
return Thread::name();
1624
// Like name() but doesn't include the protection check. This must only be
1625
// called when it is known to be safe, even though the protection check can't tell
1626
// that e.g. when this thread is the init_thread() - see instanceKlass.cpp.
1627
const char* JavaThread::name_raw() const {1628
return get_thread_name_string();
1631
// Returns a non-null representation of this thread's name, or a suitable
1632
// descriptive string if there is no set name.
1633
const char* JavaThread::get_thread_name_string(char* buf, int buflen) const {1634
const char* name_str;
1636
Thread* current = Thread::current_or_null_safe();
1637
assert(current != nullptr, "cannot be called by a detached thread");
1638
if (!current->is_Java_thread() || JavaThread::cast(current)->is_oop_safe()) {1639
// Only access threadObj() if current thread is not a JavaThread
1640
// or if it is a JavaThread that can safely access oops.
1642
oop thread_obj = threadObj();
1643
if (thread_obj != nullptr) {1644
oop name = java_lang_Thread::name(thread_obj);
1645
if (name != nullptr) {1646
if (buf == nullptr) {1647
name_str = java_lang_String::as_utf8_string(name);
1649
name_str = java_lang_String::as_utf8_string(name, buf, buflen);
1651
} else if (is_attaching_via_jni()) { // workaround for 6412693 - see 64043061652
name_str = "<no-name - thread is attaching>";
1654
name_str = "<un-named>";
1657
name_str = Thread::name();
1661
// Current JavaThread has exited...
1662
if (current == this) {1663
// ... and is asking about itself:
1664
name_str = "<no-name - current JavaThread has exited>";
1666
// ... and it can't safely determine this JavaThread's name so
1667
// use the default thread name.
1668
name_str = Thread::name();
1672
assert(name_str != nullptr, "unexpected null thread name");
1676
// Helper to extract the name from the thread oop for logging.
1677
const char* JavaThread::name_for(oop thread_obj) {1678
assert(thread_obj != nullptr, "precondition");
1679
oop name = java_lang_Thread::name(thread_obj);
1680
const char* name_str;
1681
if (name != nullptr) {1682
name_str = java_lang_String::as_utf8_string(name);
1684
name_str = "<un-named>";
1689
void JavaThread::prepare(jobject jni_thread, ThreadPriority prio) {1691
assert(Threads_lock->owner() == Thread::current(), "must have threads lock");
1692
assert(NoPriority <= prio && prio <= MaxPriority, "sanity check");
1693
// Link Java Thread object <-> C++ Thread
1695
// Get the C++ thread object (an oop) from the JNI handle (a jthread)
1696
// and put it into a new Handle. The Handle "thread_oop" can then
1697
// be used to pass the C++ thread object to other methods.
1699
// Set the Java level thread object (jthread) field of the
1700
// new thread (a JavaThread *) to C++ thread object using the
1701
// "thread_oop" handle.
1703
// Set the thread field (a JavaThread *) of the
1704
// oop representing the java_lang_Thread to the new thread (a JavaThread *).
1706
Handle thread_oop(Thread::current(),
1707
JNIHandles::resolve_non_null(jni_thread));
1708
assert(InstanceKlass::cast(thread_oop->klass())->is_linked(),
1709
"must be initialized");
1710
set_threadOopHandles(thread_oop());
1712
if (prio == NoPriority) {1713
prio = java_lang_Thread::priority(thread_oop());
1714
assert(prio != NoPriority, "A valid priority should be present");
1717
// Push the Java priority down to the native thread; needs Threads_lock
1718
Thread::set_priority(this, prio);
1720
// Add the new thread to the Threads list and set it in motion.
1721
// We must have threads lock in order to call Threads::add.
1722
// It is crucial that we do not block before the thread is
1723
// added to the Threads list for if a GC happens, then the java_thread oop
1724
// will not be visited by GC.
1726
// Publish the JavaThread* in java.lang.Thread after the JavaThread* is
1727
// on a ThreadsList. We don't want to wait for the release when the
1728
// Theads_lock is dropped somewhere in the caller since the JavaThread*
1729
// is already visible to JVM/TI via the ThreadsList.
1730
java_lang_Thread::release_set_thread(thread_oop(), this);
1733
oop JavaThread::current_park_blocker() {1734
// Support for JSR-166 locks
1735
oop thread_oop = threadObj();
1736
if (thread_oop != nullptr) {1737
return java_lang_Thread::park_blocker(thread_oop);
1742
// Print current stack trace for checked JNI warnings and JNI fatal errors.
1743
// This is the external format, selecting the platform or vthread
1744
// as applicable, and allowing for a native-only stack.
1745
void JavaThread::print_jni_stack() {1746
assert(this == JavaThread::current(), "Can't print stack of other threads");
1747
if (!has_last_Java_frame()) {1748
ResourceMark rm(this);
1749
char* buf = NEW_RESOURCE_ARRAY_RETURN_NULL(char, O_BUFLEN);
1750
if (buf == nullptr) {1751
tty->print_cr("Unable to print native stack - out of memory");1754
address lastpc = nullptr;
1755
if (os::platform_print_native_stack(tty, nullptr, buf, O_BUFLEN, lastpc)) {1756
// We have printed the native stack in platform-specific code,
1757
// so nothing else to do in this case.
1759
frame f = os::current_frame();
1760
VMError::print_native_stack(tty, f, this, true /*print_source_info */,
1761
-1 /* max stack */, buf, O_BUFLEN);
1764
print_active_stack_on(tty);
1768
void JavaThread::print_stack_on(outputStream* st) {1769
if (!has_last_Java_frame()) return;
1771
Thread* current_thread = Thread::current();
1772
ResourceMark rm(current_thread);
1773
HandleMark hm(current_thread);
1775
RegisterMap reg_map(this,
1776
RegisterMap::UpdateMap::include,
1777
RegisterMap::ProcessFrames::include,
1778
RegisterMap::WalkContinuation::skip);
1779
vframe* start_vf = platform_thread_last_java_vframe(®_map);
1781
for (vframe* f = start_vf; f != nullptr; f = f->sender()) {1782
if (f->is_java_frame()) {1783
javaVFrame* jvf = javaVFrame::cast(f);
1784
java_lang_Throwable::print_stack_element(st, jvf->method(), jvf->bci());
1786
// Print out lock information
1787
if (JavaMonitorsInStackTrace) {1788
jvf->print_lock_info_on(st, count);
1791
// Ignore non-Java frames
1794
// Bail-out case for too deep stacks if MaxJavaStackTraceDepth > 0
1796
if (MaxJavaStackTraceDepth > 0 && MaxJavaStackTraceDepth == count) return;
1800
void JavaThread::print_vthread_stack_on(outputStream* st) {1801
assert(is_vthread_mounted(), "Caller should have checked this");
1802
assert(has_last_Java_frame(), "must be");
1804
Thread* current_thread = Thread::current();
1805
ResourceMark rm(current_thread);
1806
HandleMark hm(current_thread);
1808
RegisterMap reg_map(this,
1809
RegisterMap::UpdateMap::include,
1810
RegisterMap::ProcessFrames::include,
1811
RegisterMap::WalkContinuation::include);
1812
ContinuationEntry* cont_entry = last_continuation();
1813
vframe* start_vf = last_java_vframe(®_map);
1815
for (vframe* f = start_vf; f != nullptr; f = f->sender()) {1816
// Watch for end of vthread stack
1817
if (Continuation::is_continuation_enterSpecial(f->fr())) {1818
assert(cont_entry == Continuation::get_continuation_entry_for_entry_frame(this, f->fr()), "");
1819
if (cont_entry->is_virtual_thread()) {1822
cont_entry = cont_entry->parent();
1824
if (f->is_java_frame()) {1825
javaVFrame* jvf = javaVFrame::cast(f);
1826
java_lang_Throwable::print_stack_element(st, jvf->method(), jvf->bci());
1828
// Print out lock information
1829
if (JavaMonitorsInStackTrace) {1830
jvf->print_lock_info_on(st, count);
1833
// Ignore non-Java frames
1836
// Bail-out case for too deep stacks if MaxJavaStackTraceDepth > 0
1838
if (MaxJavaStackTraceDepth > 0 && MaxJavaStackTraceDepth == count) return;
1842
void JavaThread::print_active_stack_on(outputStream* st) {1843
if (is_vthread_mounted()) {1844
print_vthread_stack_on(st);
1851
// Rebind JVMTI thread state from carrier to virtual or from virtual to carrier.
1852
JvmtiThreadState* JavaThread::rebind_to_jvmti_thread_state_of(oop thread_oop) {1853
set_jvmti_vthread(thread_oop);
1855
// unbind current JvmtiThreadState from JavaThread
1856
JvmtiThreadState::unbind_from(jvmti_thread_state(), this);
1858
// bind new JvmtiThreadState to JavaThread
1859
JvmtiThreadState::bind_to(java_lang_Thread::jvmti_thread_state(thread_oop), this);
1861
// enable interp_only_mode for virtual or carrier thread if it has pending bit
1862
JvmtiThreadState::process_pending_interp_only(this);
1864
return jvmti_thread_state();
1868
// JVMTI PopFrame support
1869
void JavaThread::popframe_preserve_args(ByteSize size_in_bytes, void* start) {1870
assert(_popframe_preserved_args == nullptr, "should not wipe out old PopFrame preserved arguments");
1871
if (in_bytes(size_in_bytes) != 0) {1872
_popframe_preserved_args = NEW_C_HEAP_ARRAY(char, in_bytes(size_in_bytes), mtThread);
1873
_popframe_preserved_args_size = in_bytes(size_in_bytes);
1874
Copy::conjoint_jbytes(start, _popframe_preserved_args, _popframe_preserved_args_size);
1878
void* JavaThread::popframe_preserved_args() {1879
return _popframe_preserved_args;
1882
ByteSize JavaThread::popframe_preserved_args_size() {1883
return in_ByteSize(_popframe_preserved_args_size);
1886
WordSize JavaThread::popframe_preserved_args_size_in_words() {1887
int sz = in_bytes(popframe_preserved_args_size());
1888
assert(sz % wordSize == 0, "argument size must be multiple of wordSize");
1889
return in_WordSize(sz / wordSize);
1892
void JavaThread::popframe_free_preserved_args() {1893
assert(_popframe_preserved_args != nullptr, "should not free PopFrame preserved arguments twice");
1894
FREE_C_HEAP_ARRAY(char, (char*)_popframe_preserved_args);
1895
_popframe_preserved_args = nullptr;
1896
_popframe_preserved_args_size = 0;
1901
void JavaThread::trace_frames() {1902
tty->print_cr("[Describe stack]");1904
for (StackFrameStream fst(this, true /* update */, true /* process_frames */); !fst.is_done(); fst.next()) {1905
tty->print(" %d. ", frame_no++);1906
fst.current()->print_value_on(tty, this);
1911
class PrintAndVerifyOopClosure: public OopClosure {1913
template <class T> inline void do_oop_work(T* p) {1914
oop obj = RawAccess<>::oop_load(p);
1915
if (obj == nullptr) return;
1916
tty->print(INTPTR_FORMAT ": ", p2i(p));
1917
if (oopDesc::is_oop_or_null(obj)) {1918
if (obj->is_objArray()) {1919
tty->print_cr("valid objArray: " INTPTR_FORMAT, p2i(obj));1924
tty->print_cr("invalid oop: " INTPTR_FORMAT, p2i(obj));1929
virtual void do_oop(oop* p) { do_oop_work(p); }1930
virtual void do_oop(narrowOop* p) { do_oop_work(p); }1934
// Print or validate the layout of stack frames
1935
void JavaThread::print_frame_layout(int depth, bool validate_only) {1937
PreserveExceptionMark pm(this);
1940
for (StackFrameStream fst(this, true, true, true); !fst.is_done(); fst.next()) {1941
fst.current()->describe(values, ++frame_no, fst.register_map());
1942
if (depth == frame_no) break;
1944
Continuation::describe(values);
1945
if (validate_only) {1948
tty->print_cr("[Describe stack layout]");1954
void JavaThread::trace_stack_from(vframe* start_vf) {1957
for (vframe* f = start_vf; f; f = f->sender()) {1958
if (f->is_java_frame()) {1959
javaVFrame::cast(f)->print_activation(vframe_no++);
1963
if (vframe_no > StackPrintLimit) {1964
tty->print_cr("...<more frames>...");1971
void JavaThread::trace_stack() {1972
if (!has_last_Java_frame()) return;
1973
Thread* current_thread = Thread::current();
1974
ResourceMark rm(current_thread);
1975
HandleMark hm(current_thread);
1976
RegisterMap reg_map(this,
1977
RegisterMap::UpdateMap::include,
1978
RegisterMap::ProcessFrames::include,
1979
RegisterMap::WalkContinuation::skip);
1980
trace_stack_from(last_java_vframe(®_map));
1986
// Slow-path increment of the held monitor counts. JNI locking is always
1988
void JavaThread::inc_held_monitor_count(intx i, bool jni) {1989
#ifdef SUPPORT_MONITOR_COUNT
1990
assert(_held_monitor_count >= 0, "Must always be non-negative: " INTX_FORMAT, _held_monitor_count);
1991
_held_monitor_count += i;
1993
assert(_jni_monitor_count >= 0, "Must always be non-negative: " INTX_FORMAT, _jni_monitor_count);
1994
_jni_monitor_count += i;
1996
assert(_held_monitor_count >= _jni_monitor_count, "Monitor count discrepancy detected - held count "
1997
INTX_FORMAT " is less than JNI count " INTX_FORMAT, _held_monitor_count, _jni_monitor_count);
2001
// Slow-path decrement of the held monitor counts. JNI unlocking is always
2003
void JavaThread::dec_held_monitor_count(intx i, bool jni) {2004
#ifdef SUPPORT_MONITOR_COUNT
2005
_held_monitor_count -= i;
2006
assert(_held_monitor_count >= 0, "Must always be greater than 0: " INTX_FORMAT, _held_monitor_count);
2008
_jni_monitor_count -= i;
2009
assert(_jni_monitor_count >= 0, "Must always be greater than 0: " INTX_FORMAT, _jni_monitor_count);
2011
// When a thread is detaching with still owned JNI monitors, the logic that releases
2012
// the monitors doesn't know to set the "jni" flag and so the counts can get out of sync.
2013
// So we skip this assert if the thread is exiting. Once all monitors are unlocked the
2014
// JNI count is directly set to zero.
2015
assert(_held_monitor_count >= _jni_monitor_count || is_exiting(), "Monitor count discrepancy detected - held count "
2016
INTX_FORMAT " is less than JNI count " INTX_FORMAT, _held_monitor_count, _jni_monitor_count);
2020
frame JavaThread::vthread_last_frame() {2021
assert (is_vthread_mounted(), "Virtual thread not mounted");
2022
return last_frame();
2025
frame JavaThread::carrier_last_frame(RegisterMap* reg_map) {2026
const ContinuationEntry* entry = vthread_continuation();
2027
guarantee (entry != nullptr, "Not a carrier thread");
2028
frame f = entry->to_frame();
2029
if (reg_map->process_frames()) {2030
entry->flush_stack_processing(this);
2032
entry->update_register_map(reg_map);
2033
return f.sender(reg_map);
2036
frame JavaThread::platform_thread_last_frame(RegisterMap* reg_map) {2037
return is_vthread_mounted() ? carrier_last_frame(reg_map) : last_frame();
2040
javaVFrame* JavaThread::last_java_vframe(const frame f, RegisterMap *reg_map) {2041
assert(reg_map != nullptr, "a map must be given");
2042
for (vframe* vf = vframe::new_vframe(&f, reg_map, this); vf; vf = vf->sender()) {2043
if (vf->is_java_frame()) return javaVFrame::cast(vf);
2048
Klass* JavaThread::security_get_caller_class(int depth) {2049
ResetNoHandleMark rnhm;
2050
HandleMark hm(Thread::current());
2052
vframeStream vfst(this);
2053
vfst.security_get_caller_frame(depth);
2054
if (!vfst.at_end()) {2055
return vfst.method()->method_holder();
2060
// Internal convenience function for millisecond resolution sleeps.
2061
bool JavaThread::sleep(jlong millis) {2063
if (millis > max_jlong / NANOUNITS_PER_MILLIUNIT) {2064
// Conversion to nanos would overflow, saturate at max
2067
nanos = millis * NANOUNITS_PER_MILLIUNIT;
2069
return sleep_nanos(nanos);
2072
// java.lang.Thread.sleep support
2073
// Returns true if sleep time elapsed as expected, and false
2074
// if the thread was interrupted.
2075
bool JavaThread::sleep_nanos(jlong nanos) {2076
assert(this == Thread::current(), "thread consistency check");
2077
assert(nanos >= 0, "nanos are in range");
2079
ParkEvent * const slp = this->_SleepEvent;
2080
// Because there can be races with thread interruption sending an unpark()
2081
// to the event, we explicitly reset it here to avoid an immediate return.
2082
// The actual interrupt state will be checked before we park().
2084
// Thread interruption establishes a happens-before ordering in the
2085
// Java Memory Model, so we need to ensure we synchronize with the
2087
OrderAccess::fence();
2089
jlong prevtime = os::javaTimeNanos();
2091
jlong nanos_remaining = nanos;
2094
// interruption has precedence over timing out
2095
if (this->is_interrupted(true)) {2099
if (nanos_remaining <= 0) {2104
ThreadBlockInVM tbivm(this);
2105
OSThreadWaitState osts(this->osthread(), false /* not Object.wait() */);
2106
slp->park_nanos(nanos_remaining);
2109
// Update elapsed time tracking
2110
jlong newtime = os::javaTimeNanos();
2111
if (newtime - prevtime < 0) {2112
// time moving backwards, should only happen if no monotonic clock
2113
// not a guarantee() because JVM should not abort on kernel/glibc bugs
2115
"unexpected time moving backwards detected in JavaThread::sleep()");
2117
nanos_remaining -= (newtime - prevtime);
2123
// Last thread running calls java.lang.Shutdown.shutdown()
2124
void JavaThread::invoke_shutdown_hooks() {2125
HandleMark hm(this);
2127
// We could get here with a pending exception, if so clear it now.
2128
if (this->has_pending_exception()) {2129
this->clear_pending_exception();
2133
Klass* shutdown_klass =
2134
SystemDictionary::resolve_or_null(vmSymbols::java_lang_Shutdown(),
2136
if (shutdown_klass != nullptr) {2137
// SystemDictionary::resolve_or_null will return null if there was
2138
// an exception. If we cannot load the Shutdown class, just don't
2139
// call Shutdown.shutdown() at all. This will mean the shutdown hooks
2140
// won't be run. Note that if a shutdown hook was registered,
2141
// the Shutdown class would have already been loaded
2142
// (Runtime.addShutdownHook will load it).
2143
JavaValue result(T_VOID);
2144
JavaCalls::call_static(&result,
2146
vmSymbols::shutdown_name(),
2147
vmSymbols::void_method_signature(),
2150
CLEAR_PENDING_EXCEPTION;
2154
void JavaThread::verify_cross_modify_fence_failure(JavaThread *thread) {2155
report_vm_error(__FILE__, __LINE__, "Cross modify fence failure", "%p", thread);
2159
// Helper function to create the java.lang.Thread object for a
2160
// VM-internal thread. The thread will have the given name, and be
2161
// a member of the "system" ThreadGroup.
2162
Handle JavaThread::create_system_thread_object(const char* name, TRAPS) {2163
Handle string = java_lang_String::create_from_str(name, CHECK_NH);
2165
// Initialize thread_oop to put it into the system threadGroup.
2166
// This is done by calling the Thread(ThreadGroup group, String name) constructor.
2167
Handle thread_group(THREAD, Universe::system_thread_group());
2169
JavaCalls::construct_new_instance(vmClasses::Thread_klass(),
2170
vmSymbols::threadgroup_string_void_signature(),
2178
// Starts the target JavaThread as a daemon of the given priority, and
2179
// bound to the given java.lang.Thread instance.
2180
// The Threads_lock is held for the duration.
2181
void JavaThread::start_internal_daemon(JavaThread* current, JavaThread* target,
2182
Handle thread_oop, ThreadPriority prio) {2184
assert(target->osthread() != nullptr, "target thread is not properly initialized");
2186
MutexLocker mu(current, Threads_lock);
2188
// Initialize the fields of the thread_oop first.
2189
if (prio != NoPriority) {2190
java_lang_Thread::set_priority(thread_oop(), prio);
2191
// Note: we don't call os::set_priority here. Possibly we should,
2192
// else all threads should call it themselves when they first run.
2195
java_lang_Thread::set_daemon(thread_oop());
2197
// Now bind the thread_oop to the target JavaThread.
2198
target->set_threadOopHandles(thread_oop());
2200
Threads::add(target); // target is now visible for safepoint/handshake
2201
// Publish the JavaThread* in java.lang.Thread after the JavaThread* is
2202
// on a ThreadsList. We don't want to wait for the release when the
2203
// Theads_lock is dropped when the 'mu' destructor is run since the
2204
// JavaThread* is already visible to JVM/TI via the ThreadsList.
2206
assert(java_lang_Thread::thread(thread_oop()) == nullptr, "must not be alive");
2207
java_lang_Thread::release_set_thread(thread_oop(), target); // isAlive == true now
2208
Thread::start(target);
2211
void JavaThread::vm_exit_on_osthread_failure(JavaThread* thread) {2212
// At this point it may be possible that no osthread was created for the
2213
// JavaThread due to lack of resources. However, since this must work
2214
// for critical system threads just check and abort if this fails.
2215
if (thread->osthread() == nullptr) {2216
// This isn't really an OOM condition, but historically this is what
2218
vm_exit_during_initialization("java.lang.OutOfMemoryError",2219
os::native_thread_creation_failed_msg());
2223
void JavaThread::pretouch_stack() {2224
// Given an established java thread stack with usable area followed by
2225
// shadow zone and reserved/yellow/red zone, pretouch the usable area ranging
2226
// from the current frame down to the start of the shadow zone.
2227
const address end = _stack_overflow_state.shadow_zone_safe_limit();
2228
if (is_in_full_stack(end)) {2229
char* p1 = (char*) alloca(1);
2230
address here = (address) &p1;
2231
if (is_in_full_stack(here) && here > end) {2232
size_t to_alloc = here - end;
2233
char* p2 = (char*) alloca(to_alloc);
2234
log_trace(os, thread)("Pretouching thread stack for " UINTX_FORMAT ": " RANGEFMT ".",2235
(uintx) osthread()->thread_id(), RANGEFMTARGS(p2, to_alloc));
2236
os::pretouch_memory(p2, p2 + to_alloc,
2237
NOT_AIX(os::vm_page_size()) AIX_ONLY(4096));
2242
// Deferred OopHandle release support.
2244
class OopHandleList : public CHeapObj<mtInternal> {2245
static const int _count = 4;
2246
OopHandle _handles[_count];
2247
OopHandleList* _next;
2250
OopHandleList(OopHandleList* next) : _next(next), _index(0) {}2251
void add(OopHandle h) {2252
assert(_index < _count, "too many additions");
2253
_handles[_index++] = h;
2256
assert(_index == _count, "usage error");
2257
for (int i = 0; i < _index; i++) {2258
_handles[i].release(JavaThread::thread_oop_storage());
2261
OopHandleList* next() const { return _next; }2264
OopHandleList* JavaThread::_oop_handle_list = nullptr;
2266
// Called by the ServiceThread to do the work of releasing
2268
void JavaThread::release_oop_handles() {2269
OopHandleList* list;
2271
MutexLocker ml(Service_lock, Mutex::_no_safepoint_check_flag);
2272
list = _oop_handle_list;
2273
_oop_handle_list = nullptr;
2275
assert(!SafepointSynchronize::is_at_safepoint(), "cannot be called at a safepoint");
2277
while (list != nullptr) {2278
OopHandleList* l = list;
2284
// Add our OopHandles for later release.
2285
void JavaThread::add_oop_handles_for_release() {2286
MutexLocker ml(Service_lock, Mutex::_no_safepoint_check_flag);
2287
OopHandleList* new_head = new OopHandleList(_oop_handle_list);
2288
new_head->add(_threadObj);
2289
new_head->add(_vthread);
2290
new_head->add(_jvmti_vthread);
2291
new_head->add(_scopedValueCache);
2292
_oop_handle_list = new_head;
2293
Service_lock->notify_all();