/* * Copyright (c) 1997, 2025, Oracle and/or its affiliates. All rights reserved. * Copyright (c) 2021, Azul Systems, Inc. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. * */ #ifndef SHARE_RUNTIME_JAVATHREAD_HPP #define SHARE_RUNTIME_JAVATHREAD_HPP #include "jni.h" #include "memory/allocation.hpp" #include "oops/oop.hpp" #include "oops/oopHandle.hpp" #include "runtime/continuationEntry.hpp" #include "runtime/frame.hpp" #include "runtime/globals.hpp" #include "runtime/handshake.hpp" #include "runtime/javaFrameAnchor.hpp" #include "runtime/lockStack.hpp" #include "runtime/park.hpp" #include "runtime/safepointMechanism.hpp" #include "runtime/stackWatermarkSet.hpp" #include "runtime/stackOverflow.hpp" #include "runtime/suspendResumeManager.hpp" #include "runtime/thread.hpp" #include "runtime/threadHeapSampler.hpp" #include "runtime/threadIdentifier.hpp" #include "runtime/threadStatisticalInfo.hpp" #include "utilities/exceptions.hpp" #include "utilities/globalDefinitions.hpp" #include "utilities/macros.hpp" #if INCLUDE_JFR #include "jfr/support/jfrThreadExtension.hpp" #include "utilities/ticks.hpp" #endif class AsyncExceptionHandshake; class DeoptResourceMark; class InternalOOMEMark; class JNIHandleBlock; class JVMCIRuntime; class JvmtiDeferredUpdates; class JvmtiSampledObjectAllocEventCollector; class JvmtiThreadState; class Metadata; class ObjectMonitor; class OopHandleList; class OopStorage; class OSThread; class ThreadsList; class ThreadSafepointState; class ThreadStatistics; class vframeArray; class vframe; class javaVFrame; class JavaThread; typedef void (*ThreadFunction)(JavaThread*, TRAPS); class EventVirtualThreadPinned; class JavaThread: public Thread { friend class VMStructs; friend class JVMCIVMStructs; friend class WhiteBox; friend class ThreadsSMRSupport; // to access _threadObj for exiting_threads_oops_do friend class HandshakeState; friend class Continuation; friend class Threads; friend class ServiceThread; // for deferred OopHandle release access private: bool _on_thread_list; // Is set when this JavaThread is added to the Threads list // All references to Java objects managed via OopHandles. These // have to be released by the ServiceThread after the JavaThread has // terminated - see add_oop_handles_for_release(). OopHandle _threadObj; // The Java level thread object OopHandle _vthread; // the value returned by Thread.currentThread(): the virtual thread, if mounted, otherwise _threadObj OopHandle _jvmti_vthread; OopHandle _scopedValueCache; static OopStorage* _thread_oop_storage; #ifdef ASSERT private: int _java_call_counter; public: int java_call_counter() { return _java_call_counter; } void inc_java_call_counter() { _java_call_counter++; } void dec_java_call_counter() { assert(_java_call_counter > 0, "Invalid nesting of JavaCallWrapper"); _java_call_counter--; } private: // restore original namespace restriction #endif // ifdef ASSERT JavaFrameAnchor _anchor; // Encapsulation of current java frame and it state ThreadFunction _entry_point; JNIEnv _jni_environment; // Deopt support DeoptResourceMark* _deopt_mark; // Holds special ResourceMark for deoptimization nmethod* _deopt_nmethod; // nmethod that is currently being deoptimized vframeArray* _vframe_array_head; // Holds the heap of the active vframeArrays vframeArray* _vframe_array_last; // Holds last vFrameArray we popped // Holds updates by JVMTI agents for compiled frames that cannot be performed immediately. They // will be carried out as soon as possible which, in most cases, is just before deoptimization of // the frame, when control returns to it. JvmtiDeferredUpdates* _jvmti_deferred_updates; // Handshake value for fixing 6243940. We need a place for the i2c // adapter to store the callee Method*. This value is NEVER live // across a gc point so it does NOT have to be gc'd // The handshake is open ended since we can't be certain that it will // be nulled. This is because we rarely ever see the race and end up // in handle_wrong_method which is the backend of the handshake. See // code in i2c adapters and handle_wrong_method. Method* _callee_target; // Used to pass back results to the interpreter or generated code running Java code. oop _vm_result_oop; // oop result is GC-preserved Metadata* _vm_result_metadata; // non-oop result // See ReduceInitialCardMarks: this holds the precise space interval of // the most recent slow path allocation for which compiled code has // elided card-marks for performance along the fast-path. MemRegion _deferred_card_mark; ObjectMonitor* volatile _current_pending_monitor; // ObjectMonitor this thread is waiting to lock bool _current_pending_monitor_is_from_java; // locking is from Java code ObjectMonitor* volatile _current_waiting_monitor; // ObjectMonitor on which this thread called Object.wait() // Active_handles points to a block of handles JNIHandleBlock* _active_handles; // One-element thread local free list JNIHandleBlock* _free_handle_block; // ID used as owner for inflated monitors. Same as the j.l.Thread.tid of the // current _vthread object, except during creation of the primordial and JNI // attached thread cases where this field can have a temporary value. int64_t _monitor_owner_id; public: void set_monitor_owner_id(int64_t id) { ThreadIdentifier::verify_id(id); _monitor_owner_id = id; } int64_t monitor_owner_id() const { int64_t id = _monitor_owner_id; ThreadIdentifier::verify_id(id); return id; } // For tracking the heavyweight monitor the thread is pending on. ObjectMonitor* current_pending_monitor() { // Use Atomic::load() to prevent data race between concurrent modification and // concurrent readers, e.g. ThreadService::get_current_contended_monitor(). // Especially, reloading pointer from thread after null check must be prevented. return Atomic::load(&_current_pending_monitor); } void set_current_pending_monitor(ObjectMonitor* monitor) { Atomic::store(&_current_pending_monitor, monitor); } void set_current_pending_monitor_is_from_java(bool from_java) { _current_pending_monitor_is_from_java = from_java; } bool current_pending_monitor_is_from_java() { return _current_pending_monitor_is_from_java; } ObjectMonitor* current_waiting_monitor() { // See the comment in current_pending_monitor() above. return Atomic::load(&_current_waiting_monitor); } void set_current_waiting_monitor(ObjectMonitor* monitor) { Atomic::store(&_current_waiting_monitor, monitor); } // JNI handle support JNIHandleBlock* active_handles() const { return _active_handles; } void set_active_handles(JNIHandleBlock* block) { _active_handles = block; } JNIHandleBlock* free_handle_block() const { return _free_handle_block; } void set_free_handle_block(JNIHandleBlock* block) { _free_handle_block = block; } void push_jni_handle_block(); void pop_jni_handle_block(); private: enum SuspendFlags { // NOTE: avoid using the sign-bit as cc generates different test code // when the sign-bit is used, and sometimes incorrectly - see CR 6398077 _obj_deopt = 0x00000008U // suspend for object reallocation and relocking for JVMTI agent }; // various suspension related flags - atomically updated volatile uint32_t _suspend_flags; inline void set_suspend_flag(SuspendFlags f); inline void clear_suspend_flag(SuspendFlags f); public: inline void set_obj_deopt_flag(); inline void clear_obj_deopt_flag(); bool is_obj_deopt_suspend() { return (_suspend_flags & _obj_deopt) != 0; } // Asynchronous exception support private: friend class InstallAsyncExceptionHandshake; friend class AsyncExceptionHandshake; friend class HandshakeState; void handle_async_exception(oop java_throwable); public: void install_async_exception(AsyncExceptionHandshake* aec = nullptr); bool has_async_exception_condition(); inline void set_pending_unsafe_access_error(); static void send_async_exception(JavaThread* jt, oop java_throwable); class NoAsyncExceptionDeliveryMark : public StackObj { friend JavaThread; JavaThread *_target; inline NoAsyncExceptionDeliveryMark(JavaThread *t); inline ~NoAsyncExceptionDeliveryMark(); }; // Safepoint support public: // Expose _thread_state for SafeFetchInt() volatile JavaThreadState _thread_state; ThreadSafepointState* _safepoint_state; // Holds information about a thread during a safepoint address _saved_exception_pc; // Saved pc of instruction where last implicit exception happened NOT_PRODUCT(bool _requires_cross_modify_fence;) // State used by VerifyCrossModifyFence #ifdef ASSERT // Debug support for checking if code allows safepoints or not. // Safepoints in the VM can happen because of allocation, invoking a VM operation, or blocking on // mutex, or blocking on an object synchronizer (Java locking). // If _no_safepoint_count is non-zero, then an assertion failure will happen in any of // the above cases. The class NoSafepointVerifier is used to set this counter. int _no_safepoint_count; // If 0, thread allow a safepoint to happen public: void inc_no_safepoint_count() { _no_safepoint_count++; } void dec_no_safepoint_count() { _no_safepoint_count--; } bool is_in_no_safepoint_scope() { return _no_safepoint_count > 0; } #endif // ASSERT public: // These functions check conditions before possibly going to a safepoint. // including NoSafepointVerifier. void check_for_valid_safepoint_state() NOT_DEBUG_RETURN; void check_possible_safepoint() NOT_DEBUG_RETURN; #ifdef ASSERT private: volatile uint64_t _visited_for_critical_count; public: void set_visited_for_critical_count(uint64_t safepoint_id) { assert(_visited_for_critical_count == 0, "Must be reset before set"); assert((safepoint_id & 0x1) == 1, "Must be odd"); _visited_for_critical_count = safepoint_id; } void reset_visited_for_critical_count(uint64_t safepoint_id) { assert(_visited_for_critical_count == safepoint_id, "Was not visited"); _visited_for_critical_count = 0; } bool was_visited_for_critical_count(uint64_t safepoint_id) const { return _visited_for_critical_count == safepoint_id; } #endif // ASSERT // JavaThread termination support public: enum TerminatedTypes { _not_terminated = 0xDEAD - 3, _thread_exiting, // JavaThread::exit() has been called for this thread _thread_gc_barrier_detached, // thread's GC barrier has been detached _thread_terminated, // JavaThread is removed from thread list _vm_exited // JavaThread is still executing native code, but VM is terminated // only VM_Exit can set _vm_exited }; private: // In general a JavaThread's _terminated field transitions as follows: // // _not_terminated => _thread_exiting => _thread_gc_barrier_detached => _thread_terminated // // _vm_exited is a special value to cover the case of a JavaThread // executing native code after the VM itself is terminated. // // A JavaThread that fails to JNI attach has these _terminated field transitions: // _not_terminated => _thread_terminated // volatile TerminatedTypes _terminated; jint _in_deopt_handler; // count of deoptimization // handlers thread is in volatile bool _doing_unsafe_access; // Thread may fault due to unsafe access bool _do_not_unlock_if_synchronized; // Do not unlock the receiver of a synchronized method (since it was // never locked) when throwing an exception. Used by interpreter only. #if INCLUDE_JVMTI volatile bool _carrier_thread_suspended; // Carrier thread is externally suspended bool _is_in_VTMS_transition; // thread is in virtual thread mount state transition bool _is_disable_suspend; // JVMTI suspend is temporarily disabled; used on current thread only bool _is_in_java_upcall; // JVMTI is doing a Java upcall, so JVMTI events must be hidden bool _VTMS_transition_mark; // used for sync between VTMS transitions and disablers bool _on_monitor_waited_event; // Avoid callee arg processing for enterSpecial when posting waited event ObjectMonitor* _contended_entered_monitor; // Monitor for pending monitor_contended_entered callback #ifdef ASSERT bool _is_VTMS_transition_disabler; // thread currently disabled VTMS transitions #endif #endif // JNI attach states: enum JNIAttachStates { _not_attaching_via_jni = 1, // thread is not attaching via JNI _attaching_via_jni, // thread is attaching via JNI _attached_via_jni // thread has attached via JNI }; // A regular JavaThread's _jni_attach_state is _not_attaching_via_jni. // A native thread that is attaching via JNI starts with a value // of _attaching_via_jni and transitions to _attached_via_jni. volatile JNIAttachStates _jni_attach_state; // In scope of an InternalOOMEMark? bool _is_in_internal_oome_mark; #if INCLUDE_JVMCI // The _pending_* fields below are used to communicate extra information // from an uncommon trap in JVMCI compiled code to the uncommon trap handler. // Communicates the DeoptReason and DeoptAction of the uncommon trap int _pending_deoptimization; // Specifies whether the uncommon trap is to bci 0 of a synchronized method // before the monitor has been acquired. bool _pending_monitorenter; // Specifies if the DeoptReason for the last uncommon trap was Reason_transfer_to_interpreter bool _pending_transfer_to_interpreter; // An id of a speculation that JVMCI compiled code can use to further describe and // uniquely identify the speculative optimization guarded by an uncommon trap. // See JVMCINMethodData::SPECULATION_LENGTH_BITS for further details. jlong _pending_failed_speculation; // These fields are mutually exclusive in terms of live ranges. union { // Communicates the pc at which the most recent implicit exception occurred // from the signal handler to a deoptimization stub. address _implicit_exception_pc; // Communicates an alternative call target to an i2c stub from a JavaCall . address _alternate_call_target; } _jvmci; // The JVMCIRuntime in a JVMCI shared library JVMCIRuntime* _libjvmci_runtime; // Support for high precision, thread sensitive counters in JVMCI compiled code. jlong* _jvmci_counters; // Fast thread locals for use by JVMCI jlong _jvmci_reserved0; jlong _jvmci_reserved1; oop _jvmci_reserved_oop0; // This field is used to keep an nmethod visible to the GC so that it and its contained oops can // be kept alive nmethod* _live_nmethod; public: static jlong* _jvmci_old_thread_counters; static void collect_counters(jlong* array, int length); bool resize_counters(int current_size, int new_size); static bool resize_all_jvmci_counters(int new_size); void set_jvmci_reserved_oop0(oop value) { _jvmci_reserved_oop0 = value; } oop get_jvmci_reserved_oop0() { return _jvmci_reserved_oop0; } void set_jvmci_reserved0(jlong value) { _jvmci_reserved0 = value; } jlong get_jvmci_reserved0() { return _jvmci_reserved0; } void set_jvmci_reserved1(jlong value) { _jvmci_reserved1 = value; } jlong get_jvmci_reserved1() { return _jvmci_reserved1; } void set_live_nmethod(nmethod* nm) { assert(_live_nmethod == nullptr, "only one"); _live_nmethod = nm; } void clear_live_nmethod() { _live_nmethod = nullptr; } private: #endif // INCLUDE_JVMCI StackOverflow _stack_overflow_state; void pretouch_stack(); // Compiler exception handling (NOTE: The _exception_oop is *NOT* the same as _pending_exception. It is // used to temp. parsing values into and out of the runtime system during exception handling for compiled // code) volatile oop _exception_oop; // Exception thrown in compiled code volatile address _exception_pc; // PC where exception happened volatile address _exception_handler_pc; // PC for handler of exception volatile int _is_method_handle_return; // true (== 1) if the current exception PC is a MethodHandle call site. private: // support for JNI critical regions jint _jni_active_critical; // count of entries into JNI critical region // Checked JNI: function name requires exception check char* _pending_jni_exception_check_fn; // For deadlock detection. int _depth_first_number; // JVMTI PopFrame support // This is set to popframe_pending to signal that top Java frame should be popped immediately int _popframe_condition; // If reallocation of scalar replaced objects fails, we throw OOM // and during exception propagation, pop the top // _frames_to_pop_failed_realloc frames, the ones that reference // failed reallocations. int _frames_to_pop_failed_realloc; ContinuationEntry* _cont_entry; intptr_t* _cont_fastpath; // the sp of the oldest known interpreted/call_stub/upcall_stub/native_wrapper // frame inside the continuation that we know about int _cont_fastpath_thread_state; // whether global thread state allows continuation fastpath (JVMTI) // It's signed for error detection. intx _held_monitor_count; // used by continuations for fast lock detection intx _jni_monitor_count; ObjectMonitor* _unlocked_inflated_monitor; // This is the field we poke in the interpreter and native // wrapper (Object.wait) to check for preemption. address _preempt_alternate_return; // When preempting on monitorenter we could have acquired the // monitor after freezing all vthread frames. In that case we // set this field so that in the preempt stub we call thaw again // instead of unmounting. bool _preemption_cancelled; // For Object.wait() we set this field to know if we need to // throw IE at the end of thawing before returning to Java. bool _pending_interrupted_exception; public: bool preemption_cancelled() { return _preemption_cancelled; } void set_preemption_cancelled(bool b) { _preemption_cancelled = b; } bool pending_interrupted_exception() { return _pending_interrupted_exception; } void set_pending_interrupted_exception(bool b) { _pending_interrupted_exception = b; } bool preempting() { return _preempt_alternate_return != nullptr; } void set_preempt_alternate_return(address val) { _preempt_alternate_return = val; } private: friend class VMThread; friend class ThreadWaitTransition; friend class VM_Exit; // Stack watermark barriers. StackWatermarks _stack_watermarks; public: inline StackWatermarks* stack_watermarks() { return &_stack_watermarks; } public: // Constructor JavaThread(MemTag mem_tag = mtThread); // delegating constructor JavaThread(ThreadFunction entry_point, size_t stack_size = 0, MemTag mem_tag = mtThread); ~JavaThread(); // Factory method to create a new JavaThread whose attach state is "is attaching" static JavaThread* create_attaching_thread(); #ifdef ASSERT // verify this JavaThread hasn't be published in the Threads::list yet void verify_not_published(); #endif // ASSERT StackOverflow* stack_overflow_state() { return &_stack_overflow_state; } //JNI functiontable getter/setter for JVMTI jni function table interception API. void set_jni_functions(struct JNINativeInterface_* functionTable) { _jni_environment.functions = functionTable; } struct JNINativeInterface_* get_jni_functions() { return (struct JNINativeInterface_ *)_jni_environment.functions; } // This function is called at thread creation to allow // platform specific thread variables to be initialized. void cache_global_variables(); // Executes Shutdown.shutdown() void invoke_shutdown_hooks(); // Cleanup on thread exit enum ExitType { normal_exit, jni_detach }; void exit(bool destroy_vm, ExitType exit_type = normal_exit); void cleanup_failed_attach_current_thread(bool is_daemon); // Testers virtual bool is_Java_thread() const { return true; } virtual bool can_call_java() const { return true; } virtual bool is_active_Java_thread() const; // Thread oop. threadObj() can be null for initial JavaThread // (or for threads attached via JNI) oop threadObj() const; void set_threadOopHandles(oop p); oop vthread() const; void set_vthread(oop p); oop scopedValueCache() const; void set_scopedValueCache(oop p); void clear_scopedValueBindings(); oop jvmti_vthread() const; void set_jvmti_vthread(oop p); oop vthread_or_thread() const; // Prepare thread and add to priority queue. If a priority is // not specified, use the priority of the thread object. Threads_lock // must be held while this function is called. void prepare(jobject jni_thread, ThreadPriority prio=NoPriority); void set_saved_exception_pc(address pc) { _saved_exception_pc = pc; } address saved_exception_pc() { return _saved_exception_pc; } ThreadFunction entry_point() const { return _entry_point; } // Allocates a new Java level thread object for this thread. thread_name may be null. void allocate_threadObj(Handle thread_group, const char* thread_name, bool daemon, TRAPS); // Last frame anchor routines JavaFrameAnchor* frame_anchor(void) { return &_anchor; } // last_Java_sp bool has_last_Java_frame() const { return _anchor.has_last_Java_frame(); } intptr_t* last_Java_sp() const { return _anchor.last_Java_sp(); } // last_Java_pc address last_Java_pc(void) { return _anchor.last_Java_pc(); } // Safepoint support inline JavaThreadState thread_state() const; inline void set_thread_state(JavaThreadState s); inline void set_thread_state_fence(JavaThreadState s); // fence after setting thread state inline ThreadSafepointState* safepoint_state() const; inline void set_safepoint_state(ThreadSafepointState* state); inline bool is_at_poll_safepoint(); // JavaThread termination and lifecycle support: void smr_delete(); bool on_thread_list() const { return _on_thread_list; } void set_on_thread_list() { _on_thread_list = true; } // thread has called JavaThread::exit(), thread's GC barrier is detached // or thread is terminated bool is_exiting() const; // thread's GC barrier is NOT detached and thread is NOT terminated bool is_oop_safe() const; // thread is terminated (no longer on the threads list); the thread must // be protected by a ThreadsListHandle to avoid potential crashes. bool check_is_terminated(TerminatedTypes l_terminated) const { return l_terminated == _thread_terminated || l_terminated == _vm_exited; } bool is_terminated() const; void set_terminated(TerminatedTypes t); void block_if_vm_exited(); bool doing_unsafe_access() { return _doing_unsafe_access; } void set_doing_unsafe_access(bool val) { _doing_unsafe_access = val; } bool do_not_unlock_if_synchronized() { return _do_not_unlock_if_synchronized; } void set_do_not_unlock_if_synchronized(bool val) { _do_not_unlock_if_synchronized = val; } SafepointMechanism::ThreadData* poll_data() { return &_poll_data; } static ByteSize polling_word_offset() { ByteSize offset = byte_offset_of(Thread, _poll_data) + byte_offset_of(SafepointMechanism::ThreadData, _polling_word); // At least on x86_64, safepoint polls encode the offset as disp8 imm. assert(in_bytes(offset) < 128, "Offset >= 128"); return offset; } static ByteSize polling_page_offset() { ByteSize offset = byte_offset_of(Thread, _poll_data) + byte_offset_of(SafepointMechanism::ThreadData, _polling_page); // At least on x86_64, safepoint polls encode the offset as disp8 imm. assert(in_bytes(offset) < 128, "Offset >= 128"); return offset; } void set_requires_cross_modify_fence(bool val) PRODUCT_RETURN NOT_PRODUCT({ _requires_cross_modify_fence = val; }) // Continuation support ContinuationEntry* last_continuation() const { return _cont_entry; } void set_cont_fastpath(intptr_t* x) { _cont_fastpath = x; } void push_cont_fastpath(intptr_t* sp) { if (sp > _cont_fastpath) _cont_fastpath = sp; } void set_cont_fastpath_thread_state(bool x) { _cont_fastpath_thread_state = (int)x; } intptr_t* raw_cont_fastpath() const { return _cont_fastpath; } bool cont_fastpath() const { return _cont_fastpath == nullptr && _cont_fastpath_thread_state != 0; } bool cont_fastpath_thread_state() const { return _cont_fastpath_thread_state != 0; } void inc_held_monitor_count(intx i = 1, bool jni = false); void dec_held_monitor_count(intx i = 1, bool jni = false); intx held_monitor_count() { return _held_monitor_count; } intx jni_monitor_count() { return _jni_monitor_count; } void clear_jni_monitor_count() { _jni_monitor_count = 0; } // Support for SharedRuntime::monitor_exit_helper() ObjectMonitor* unlocked_inflated_monitor() const { return _unlocked_inflated_monitor; } void clear_unlocked_inflated_monitor() { _unlocked_inflated_monitor = nullptr; } inline bool is_vthread_mounted() const; inline const ContinuationEntry* vthread_continuation() const; private: DEBUG_ONLY(void verify_frame_info();) // Support for thread handshake operations HandshakeState _handshake; public: HandshakeState* handshake_state() { return &_handshake; } // A JavaThread can always safely operate on it self and other threads // can do it safely if they are the active handshaker. bool is_handshake_safe_for(Thread* th) const { return _handshake.active_handshaker() == th || this == th; } // Suspend/resume support for JavaThread // higher-level suspension/resume logic called by the public APIs private: SuspendResumeManager _suspend_resume_manager; public: bool java_suspend(bool register_vthread_SR); bool java_resume(bool register_vthread_SR); bool is_suspended() { return _suspend_resume_manager.is_suspended(); } SuspendResumeManager* suspend_resume_manager() { return &_suspend_resume_manager; } // Check for async exception in addition to safepoint. static void check_special_condition_for_native_trans(JavaThread *thread); // Synchronize with another thread that is deoptimizing objects of the // current thread, i.e. reverts optimizations based on escape analysis. void wait_for_object_deoptimization(); #if INCLUDE_JVMTI inline bool set_carrier_thread_suspended(); inline bool clear_carrier_thread_suspended(); bool is_carrier_thread_suspended() const { return Atomic::load(&_carrier_thread_suspended); } bool is_in_VTMS_transition() const { return _is_in_VTMS_transition; } void set_is_in_VTMS_transition(bool val); bool is_disable_suspend() const { return _is_disable_suspend; } void toggle_is_disable_suspend() { _is_disable_suspend = !_is_disable_suspend; }; bool is_in_java_upcall() const { return _is_in_java_upcall; } void toggle_is_in_java_upcall() { _is_in_java_upcall = !_is_in_java_upcall; }; bool VTMS_transition_mark() const { return Atomic::load(&_VTMS_transition_mark); } void set_VTMS_transition_mark(bool val) { Atomic::store(&_VTMS_transition_mark, val); } // Temporarily skip posting JVMTI events for safety reasons when executions is in a critical section: // - is in a VTMS transition (_is_in_VTMS_transition) // - is in an interruptLock or similar critical section (_is_disable_suspend) // - JVMTI is making a Java upcall (_is_in_java_upcall) bool should_hide_jvmti_events() const { return _is_in_VTMS_transition || _is_disable_suspend || _is_in_java_upcall; } bool on_monitor_waited_event() { return _on_monitor_waited_event; } void set_on_monitor_waited_event(bool val) { _on_monitor_waited_event = val; } bool pending_contended_entered_event() { return _contended_entered_monitor != nullptr; } ObjectMonitor* contended_entered_monitor() { return _contended_entered_monitor; } #ifdef ASSERT bool is_VTMS_transition_disabler() const { return _is_VTMS_transition_disabler; } void set_is_VTMS_transition_disabler(bool val); #endif #endif void set_contended_entered_monitor(ObjectMonitor* val) NOT_JVMTI_RETURN JVMTI_ONLY({ _contended_entered_monitor = val; }) // Support for object deoptimization and JFR suspension void handle_special_runtime_exit_condition(); bool has_special_runtime_exit_condition() { return (_suspend_flags & _obj_deopt) != 0; } // Stack-locking support (not for LM_LIGHTWEIGHT) bool is_lock_owned(address adr) const; // Accessors for vframe array top // The linked list of vframe arrays are sorted on sp. This means when we // unpack the head must contain the vframe array to unpack. void set_vframe_array_head(vframeArray* value) { _vframe_array_head = value; } vframeArray* vframe_array_head() const { return _vframe_array_head; } // Side structure for deferring update of java frame locals until deopt occurs JvmtiDeferredUpdates* deferred_updates() const { return _jvmti_deferred_updates; } void set_deferred_updates(JvmtiDeferredUpdates* du) { _jvmti_deferred_updates = du; } // These only really exist to make debugging deopt problems simpler void set_vframe_array_last(vframeArray* value) { _vframe_array_last = value; } vframeArray* vframe_array_last() const { return _vframe_array_last; } // The special resourceMark used during deoptimization void set_deopt_mark(DeoptResourceMark* value) { _deopt_mark = value; } DeoptResourceMark* deopt_mark(void) { return _deopt_mark; } void set_deopt_compiled_method(nmethod* nm) { _deopt_nmethod = nm; } nmethod* deopt_compiled_method() { return _deopt_nmethod; } Method* callee_target() const { return _callee_target; } void set_callee_target (Method* x) { _callee_target = x; } // Oop results of vm runtime calls oop vm_result_oop() const { return _vm_result_oop; } void set_vm_result_oop(oop x) { _vm_result_oop = x; } void set_vm_result_metadata(Metadata* x) { _vm_result_metadata = x; } MemRegion deferred_card_mark() const { return _deferred_card_mark; } void set_deferred_card_mark(MemRegion mr) { _deferred_card_mark = mr; } // Is thread in scope of an InternalOOMEMark? bool is_in_internal_oome_mark() const { return _is_in_internal_oome_mark; } void set_is_in_internal_oome_mark(bool b) { _is_in_internal_oome_mark = b; } #if INCLUDE_JVMCI jlong pending_failed_speculation() const { return _pending_failed_speculation; } void set_pending_monitorenter(bool b) { _pending_monitorenter = b; } void set_pending_deoptimization(int reason) { _pending_deoptimization = reason; } void set_pending_failed_speculation(jlong failed_speculation) { _pending_failed_speculation = failed_speculation; } void set_pending_transfer_to_interpreter(bool b) { _pending_transfer_to_interpreter = b; } void set_jvmci_alternate_call_target(address a) { assert(_jvmci._alternate_call_target == nullptr, "must be"); _jvmci._alternate_call_target = a; } void set_jvmci_implicit_exception_pc(address a) { assert(_jvmci._implicit_exception_pc == nullptr, "must be"); _jvmci._implicit_exception_pc = a; } JVMCIRuntime* libjvmci_runtime() const { return _libjvmci_runtime; } void set_libjvmci_runtime(JVMCIRuntime* rt) { assert((_libjvmci_runtime == nullptr && rt != nullptr) || (_libjvmci_runtime != nullptr && rt == nullptr), "must be"); _libjvmci_runtime = rt; } #endif // INCLUDE_JVMCI // Exception handling for compiled methods oop exception_oop() const; address exception_pc() const { return _exception_pc; } void set_exception_oop(oop o); void set_exception_pc(address a) { _exception_pc = a; } void set_exception_handler_pc(address a) { _exception_handler_pc = a; } void set_is_method_handle_return(bool value) { _is_method_handle_return = value ? 1 : 0; } void clear_exception_oop_and_pc() { set_exception_oop(nullptr); set_exception_pc(nullptr); } // Check if address is in the usable part of the stack (excludes protected // guard pages). Can be applied to any thread and is an approximation for // using is_in_live_stack when the query has to happen from another thread. bool is_in_usable_stack(address adr) const { return is_in_stack_range_incl(adr, _stack_overflow_state.stack_reserved_zone_base()); } // Misc. accessors/mutators static ByteSize scopedValueCache_offset() { return byte_offset_of(JavaThread, _scopedValueCache); } // For assembly stub generation static ByteSize threadObj_offset() { return byte_offset_of(JavaThread, _threadObj); } static ByteSize vthread_offset() { return byte_offset_of(JavaThread, _vthread); } static ByteSize jni_environment_offset() { return byte_offset_of(JavaThread, _jni_environment); } static ByteSize pending_jni_exception_check_fn_offset() { return byte_offset_of(JavaThread, _pending_jni_exception_check_fn); } static ByteSize last_Java_sp_offset() { return byte_offset_of(JavaThread, _anchor) + JavaFrameAnchor::last_Java_sp_offset(); } static ByteSize last_Java_pc_offset() { return byte_offset_of(JavaThread, _anchor) + JavaFrameAnchor::last_Java_pc_offset(); } static ByteSize frame_anchor_offset() { return byte_offset_of(JavaThread, _anchor); } static ByteSize callee_target_offset() { return byte_offset_of(JavaThread, _callee_target); } static ByteSize vm_result_oop_offset() { return byte_offset_of(JavaThread, _vm_result_oop); } static ByteSize vm_result_metadata_offset() { return byte_offset_of(JavaThread, _vm_result_metadata); } static ByteSize thread_state_offset() { return byte_offset_of(JavaThread, _thread_state); } static ByteSize saved_exception_pc_offset() { return byte_offset_of(JavaThread, _saved_exception_pc); } static ByteSize osthread_offset() { return byte_offset_of(JavaThread, _osthread); } #if INCLUDE_JVMCI static ByteSize pending_deoptimization_offset() { return byte_offset_of(JavaThread, _pending_deoptimization); } static ByteSize pending_monitorenter_offset() { return byte_offset_of(JavaThread, _pending_monitorenter); } static ByteSize jvmci_alternate_call_target_offset() { return byte_offset_of(JavaThread, _jvmci._alternate_call_target); } static ByteSize jvmci_implicit_exception_pc_offset() { return byte_offset_of(JavaThread, _jvmci._implicit_exception_pc); } static ByteSize jvmci_counters_offset() { return byte_offset_of(JavaThread, _jvmci_counters); } #endif // INCLUDE_JVMCI static ByteSize exception_oop_offset() { return byte_offset_of(JavaThread, _exception_oop); } static ByteSize exception_pc_offset() { return byte_offset_of(JavaThread, _exception_pc); } static ByteSize exception_handler_pc_offset() { return byte_offset_of(JavaThread, _exception_handler_pc); } static ByteSize is_method_handle_return_offset() { return byte_offset_of(JavaThread, _is_method_handle_return); } static ByteSize active_handles_offset() { return byte_offset_of(JavaThread, _active_handles); } // StackOverflow offsets static ByteSize stack_overflow_limit_offset() { return byte_offset_of(JavaThread, _stack_overflow_state._stack_overflow_limit); } static ByteSize stack_guard_state_offset() { return byte_offset_of(JavaThread, _stack_overflow_state._stack_guard_state); } static ByteSize reserved_stack_activation_offset() { return byte_offset_of(JavaThread, _stack_overflow_state._reserved_stack_activation); } static ByteSize shadow_zone_safe_limit() { return byte_offset_of(JavaThread, _stack_overflow_state._shadow_zone_safe_limit); } static ByteSize shadow_zone_growth_watermark() { return byte_offset_of(JavaThread, _stack_overflow_state._shadow_zone_growth_watermark); } static ByteSize suspend_flags_offset() { return byte_offset_of(JavaThread, _suspend_flags); } static ByteSize do_not_unlock_if_synchronized_offset() { return byte_offset_of(JavaThread, _do_not_unlock_if_synchronized); } static ByteSize should_post_on_exceptions_flag_offset() { return byte_offset_of(JavaThread, _should_post_on_exceptions_flag); } static ByteSize doing_unsafe_access_offset() { return byte_offset_of(JavaThread, _doing_unsafe_access); } NOT_PRODUCT(static ByteSize requires_cross_modify_fence_offset() { return byte_offset_of(JavaThread, _requires_cross_modify_fence); }) static ByteSize monitor_owner_id_offset() { return byte_offset_of(JavaThread, _monitor_owner_id); } static ByteSize cont_entry_offset() { return byte_offset_of(JavaThread, _cont_entry); } static ByteSize cont_fastpath_offset() { return byte_offset_of(JavaThread, _cont_fastpath); } static ByteSize held_monitor_count_offset() { return byte_offset_of(JavaThread, _held_monitor_count); } static ByteSize jni_monitor_count_offset() { return byte_offset_of(JavaThread, _jni_monitor_count); } static ByteSize preemption_cancelled_offset() { return byte_offset_of(JavaThread, _preemption_cancelled); } static ByteSize preempt_alternate_return_offset() { return byte_offset_of(JavaThread, _preempt_alternate_return); } static ByteSize unlocked_inflated_monitor_offset() { return byte_offset_of(JavaThread, _unlocked_inflated_monitor); } #if INCLUDE_JVMTI static ByteSize is_in_VTMS_transition_offset() { return byte_offset_of(JavaThread, _is_in_VTMS_transition); } static ByteSize is_disable_suspend_offset() { return byte_offset_of(JavaThread, _is_disable_suspend); } #endif // Returns the jni environment for this thread JNIEnv* jni_environment() { return &_jni_environment; } // Returns the current thread as indicated by the given JNIEnv. // We don't assert it is Thread::current here as that is done at the // external JNI entry points where the JNIEnv is passed into the VM. static JavaThread* thread_from_jni_environment(JNIEnv* env) { JavaThread* current = reinterpret_cast(((intptr_t)env - in_bytes(jni_environment_offset()))); // We can't normally get here in a thread that has completed its // execution and so "is_terminated", except when the call is from // AsyncGetCallTrace, which can be triggered by a signal at any point in // a thread's lifecycle. A thread is also considered terminated if the VM // has exited, so we have to check this and block in case this is a daemon // thread returning to the VM (the JNI DirectBuffer entry points rely on // this). if (current->is_terminated()) { current->block_if_vm_exited(); } return current; } // JNI critical regions. These can nest. bool in_critical() { return _jni_active_critical > 0; } bool in_last_critical() { return _jni_active_critical == 1; } inline void enter_critical(); void exit_critical() { assert(Thread::current() == this, "this must be current thread"); _jni_active_critical--; assert(_jni_active_critical >= 0, "JNI critical nesting problem?"); } // Atomic version; invoked by a thread other than the owning thread. bool in_critical_atomic() { return Atomic::load(&_jni_active_critical) > 0; } // Checked JNI: is the programmer required to check for exceptions, if so specify // which function name. Returning to a Java frame should implicitly clear the // pending check, this is done for Native->Java transitions (i.e. user JNI code). // VM->Java transitions are not cleared, it is expected that JNI code enclosed // within ThreadToNativeFromVM makes proper exception checks (i.e. VM internal). bool is_pending_jni_exception_check() const { return _pending_jni_exception_check_fn != nullptr; } void clear_pending_jni_exception_check() { _pending_jni_exception_check_fn = nullptr; } const char* get_pending_jni_exception_check() const { return _pending_jni_exception_check_fn; } void set_pending_jni_exception_check(const char* fn_name) { _pending_jni_exception_check_fn = (char*) fn_name; } // For deadlock detection int depth_first_number() { return _depth_first_number; } void set_depth_first_number(int dfn) { _depth_first_number = dfn; } public: bool in_deopt_handler() const { return _in_deopt_handler > 0; } void inc_in_deopt_handler() { _in_deopt_handler++; } void dec_in_deopt_handler() { assert(_in_deopt_handler > 0, "mismatched deopt nesting"); if (_in_deopt_handler > 0) { // robustness _in_deopt_handler--; } } private: void set_entry_point(ThreadFunction entry_point) { _entry_point = entry_point; } // factor out low-level mechanics for use in both normal and error cases const char* get_thread_name_string(char* buf = nullptr, int buflen = 0) const; public: // Frame iteration; calls the function f for all frames on the stack void frames_do(void f(frame*, const RegisterMap*)); // Memory operations void oops_do_frames(OopClosure* f, NMethodClosure* cf); void oops_do_no_frames(OopClosure* f, NMethodClosure* cf); // GC operations virtual void nmethods_do(NMethodClosure* cf); // RedefineClasses Support void metadata_do(MetadataClosure* f); // Debug method asserting thread states are correct during a handshake operation. DEBUG_ONLY(void verify_states_for_handshake();) // Misc. operations const char* name() const; const char* name_raw() const; const char* type_name() const { return "JavaThread"; } static const char* name_for(oop thread_obj); void print_on(outputStream* st, bool print_extended_info) const; void print_on(outputStream* st) const { print_on(st, false); } void print() const; void print_thread_state_on(outputStream*) const; void print_on_error(outputStream* st, char* buf, int buflen) const; void print_name_on_error(outputStream* st, char* buf, int buflen) const; void verify(); // Accessing frames frame last_frame() { _anchor.make_walkable(); return pd_last_frame(); } javaVFrame* last_java_vframe(RegisterMap* reg_map) { return last_java_vframe(last_frame(), reg_map); } frame carrier_last_frame(RegisterMap* reg_map); javaVFrame* carrier_last_java_vframe(RegisterMap* reg_map) { return last_java_vframe(carrier_last_frame(reg_map), reg_map); } frame vthread_last_frame(); javaVFrame* vthread_last_java_vframe(RegisterMap* reg_map) { return last_java_vframe(vthread_last_frame(), reg_map); } frame platform_thread_last_frame(RegisterMap* reg_map); javaVFrame* platform_thread_last_java_vframe(RegisterMap* reg_map) { return last_java_vframe(platform_thread_last_frame(reg_map), reg_map); } javaVFrame* last_java_vframe(const frame f, RegisterMap* reg_map); // Returns method at 'depth' java or native frames down the stack // Used for security checks Klass* security_get_caller_class(int depth); // Print stack trace in external format // These variants print carrier/platform thread information only. void print_stack_on(outputStream* st); void print_stack() { print_stack_on(tty); } // This prints the currently mounted virtual thread. void print_vthread_stack_on(outputStream* st); // This prints the active stack: either carrier/platform or virtual. void print_active_stack_on(outputStream* st); // Print current stack trace for checked JNI warnings and JNI fatal errors. // This is the external format from above, but selecting the platform // or vthread as applicable. void print_jni_stack(); // Print stack traces in various internal formats void trace_stack() PRODUCT_RETURN; void trace_stack_from(vframe* start_vf) PRODUCT_RETURN; void trace_frames() PRODUCT_RETURN; // Print an annotated view of the stack frames void print_frame_layout(int depth = 0, bool validate_only = false) NOT_DEBUG_RETURN; void validate_frame_layout() { print_frame_layout(0, true); } // Function for testing deoptimization void deoptimize(); void make_zombies(); void deoptimize_marked_methods(); public: // Returns the running thread as a JavaThread static JavaThread* current() { return JavaThread::cast(Thread::current()); } // Returns the current thread as a JavaThread, or nullptr if not attached static inline JavaThread* current_or_null(); // Casts static JavaThread* cast(Thread* t) { assert(t->is_Java_thread(), "incorrect cast to JavaThread"); return static_cast(t); } static const JavaThread* cast(const Thread* t) { assert(t->is_Java_thread(), "incorrect cast to const JavaThread"); return static_cast(t); } // Returns the active Java thread. Do not use this if you know you are calling // from a JavaThread, as it's slower than JavaThread::current. If called from // the VMThread, it also returns the JavaThread that instigated the VMThread's // operation. You may not want that either. static JavaThread* active(); protected: virtual void pre_run(); virtual void run(); void thread_main_inner(); virtual void post_run(); public: // Thread local information maintained by JVMTI. void set_jvmti_thread_state(JvmtiThreadState *value) { _jvmti_thread_state = value; } // A JvmtiThreadState is lazily allocated. This jvmti_thread_state() // getter is used to get this JavaThread's JvmtiThreadState if it has // one which means null can be returned. JvmtiThreadState::state_for() // is used to get the specified JavaThread's JvmtiThreadState if it has // one or it allocates a new JvmtiThreadState for the JavaThread and // returns it. JvmtiThreadState::state_for() will return null only if // the specified JavaThread is exiting. JvmtiThreadState *jvmti_thread_state() const { return _jvmti_thread_state; } static ByteSize jvmti_thread_state_offset() { return byte_offset_of(JavaThread, _jvmti_thread_state); } #if INCLUDE_JVMTI // Rebind JVMTI thread state from carrier to virtual or from virtual to carrier. JvmtiThreadState *rebind_to_jvmti_thread_state_of(oop thread_oop); #endif // JVMTI PopFrame support // Setting and clearing popframe_condition // All of these enumerated values are bits. popframe_pending // indicates that a PopFrame() has been requested and not yet been // completed. popframe_processing indicates that that PopFrame() is in // the process of being completed. popframe_force_deopt_reexecution_bit // indicates that special handling is required when returning to a // deoptimized caller. enum PopCondition { popframe_inactive = 0x00, popframe_pending_bit = 0x01, popframe_processing_bit = 0x02, popframe_force_deopt_reexecution_bit = 0x04 }; PopCondition popframe_condition() { return (PopCondition) _popframe_condition; } void set_popframe_condition(PopCondition c) { _popframe_condition = c; } void set_popframe_condition_bit(PopCondition c) { _popframe_condition |= c; } void clear_popframe_condition() { _popframe_condition = popframe_inactive; } static ByteSize popframe_condition_offset() { return byte_offset_of(JavaThread, _popframe_condition); } bool has_pending_popframe() { return (popframe_condition() & popframe_pending_bit) != 0; } bool popframe_forcing_deopt_reexecution() { return (popframe_condition() & popframe_force_deopt_reexecution_bit) != 0; } bool pop_frame_in_process(void) { return ((_popframe_condition & popframe_processing_bit) != 0); } void set_pop_frame_in_process(void) { _popframe_condition |= popframe_processing_bit; } void clr_pop_frame_in_process(void) { _popframe_condition &= ~popframe_processing_bit; } int frames_to_pop_failed_realloc() const { return _frames_to_pop_failed_realloc; } void set_frames_to_pop_failed_realloc(int nb) { _frames_to_pop_failed_realloc = nb; } void dec_frames_to_pop_failed_realloc() { _frames_to_pop_failed_realloc--; } private: // Saved incoming arguments to popped frame. // Used only when popped interpreted frame returns to deoptimized frame. void* _popframe_preserved_args; int _popframe_preserved_args_size; public: void popframe_preserve_args(ByteSize size_in_bytes, void* start); void* popframe_preserved_args(); ByteSize popframe_preserved_args_size(); WordSize popframe_preserved_args_size_in_words(); void popframe_free_preserved_args(); private: JvmtiThreadState *_jvmti_thread_state; // Used by the interpreter in fullspeed mode for frame pop, method // entry, method exit and single stepping support. This field is // only set to non-zero at a safepoint or using a direct handshake // (see EnterInterpOnlyModeClosure). // It can be set to zero asynchronously to this threads execution (i.e., without // safepoint/handshake or a lock) so we have to be very careful. // Accesses by other threads are synchronized using JvmtiThreadState_lock though. // This field is checked by the interpreter which expects it to be an integer. int _interp_only_mode; public: // used by the interpreter for fullspeed debugging support (see above) static ByteSize interp_only_mode_offset() { return byte_offset_of(JavaThread, _interp_only_mode); } bool is_interp_only_mode() { return (_interp_only_mode != 0); } void set_interp_only_mode(bool val) { _interp_only_mode = val ? 1 : 0; } // support for cached flag that indicates whether exceptions need to be posted for this thread // if this is false, we can avoid deoptimizing when events are thrown // this gets set to reflect whether jvmtiExport::post_exception_throw would actually do anything private: int _should_post_on_exceptions_flag; public: void set_should_post_on_exceptions_flag(int val) { _should_post_on_exceptions_flag = val; } private: ThreadStatistics *_thread_stat; public: ThreadStatistics* get_thread_stat() const { return _thread_stat; } // Return a blocker object for which this thread is blocked parking. oop current_park_blocker(); private: static size_t _stack_size_at_create; public: static inline size_t stack_size_at_create(void) { return _stack_size_at_create; } static inline void set_stack_size_at_create(size_t value) { _stack_size_at_create = value; } // Machine dependent stuff #include OS_CPU_HEADER(javaThread) // JSR166 per-thread parker private: Parker _parker; public: Parker* parker() { return &_parker; } public: // clearing/querying jni attach status bool is_attaching_via_jni() const { return _jni_attach_state == _attaching_via_jni; } bool has_attached_via_jni() const { return is_attaching_via_jni() || _jni_attach_state == _attached_via_jni; } inline void set_done_attaching_via_jni(); // Stack dump assistance: // Track the class we want to initialize but for which we have to wait // on its init_lock() because it is already being initialized. void set_class_to_be_initialized(InstanceKlass* k); InstanceKlass* class_to_be_initialized() const; // Track executing class initializer, see ThreadInClassInitializer void set_class_being_initialized(InstanceKlass* k); InstanceKlass* class_being_initialized() const; private: InstanceKlass* _class_to_be_initialized; InstanceKlass* _class_being_initialized; // java.lang.Thread.sleep support ParkEvent * _SleepEvent; #if INCLUDE_JFR // Support for jdk.VirtualThreadPinned event freeze_result _last_freeze_fail_result; Ticks _last_freeze_fail_time; #endif public: bool sleep(jlong millis); bool sleep_nanos(jlong nanos); // java.lang.Thread interruption support void interrupt(); bool is_interrupted(bool clear_interrupted); #if INCLUDE_JFR // Support for jdk.VirtualThreadPinned event freeze_result last_freeze_fail_result() { return _last_freeze_fail_result; } Ticks& last_freeze_fail_time() { return _last_freeze_fail_time; } void set_last_freeze_fail_result(freeze_result result); #endif void post_vthread_pinned_event(EventVirtualThreadPinned* event, const char* op, freeze_result result) NOT_JFR_RETURN(); // This is only for use by JVMTI RawMonitorWait. It emulates the actions of // the Java code in Object::wait which are not present in RawMonitorWait. bool get_and_clear_interrupted(); private: LockStack _lock_stack; OMCache _om_cache; public: LockStack& lock_stack() { return _lock_stack; } static ByteSize lock_stack_offset() { return byte_offset_of(JavaThread, _lock_stack); } // Those offsets are used in code generators to access the LockStack that is embedded in this // JavaThread structure. Those accesses are relative to the current thread, which // is typically in a dedicated register. static ByteSize lock_stack_top_offset() { return lock_stack_offset() + LockStack::top_offset(); } static ByteSize lock_stack_base_offset() { return lock_stack_offset() + LockStack::base_offset(); } static ByteSize om_cache_offset() { return byte_offset_of(JavaThread, _om_cache); } static ByteSize om_cache_oops_offset() { return om_cache_offset() + OMCache::entries_offset(); } void om_set_monitor_cache(ObjectMonitor* monitor); void om_clear_monitor_cache(); ObjectMonitor* om_get_from_monitor_cache(oop obj); static OopStorage* thread_oop_storage(); static void verify_cross_modify_fence_failure(JavaThread *thread) PRODUCT_RETURN; // Helper function to create the java.lang.Thread object for a // VM-internal thread. The thread will have the given name and be // part of the System ThreadGroup. static Handle create_system_thread_object(const char* name, TRAPS); // Helper function to start a VM-internal daemon thread. // E.g. ServiceThread, NotificationThread, CompilerThread etc. static void start_internal_daemon(JavaThread* current, JavaThread* target, Handle thread_oop, ThreadPriority prio); // Helper function to do vm_exit_on_initialization for osthread // resource allocation failure. static void vm_exit_on_osthread_failure(JavaThread* thread); // Deferred OopHandle release support private: // List of OopHandles to be released - guarded by the Service_lock. static OopHandleList* _oop_handle_list; // Add our OopHandles to the list for the service thread to release. void add_oop_handles_for_release(); // Called by the ServiceThread to release the OopHandles. static void release_oop_handles(); // Called by the ServiceThread to poll if there are any OopHandles to release. // Called when holding the Service_lock. static bool has_oop_handles_to_release() { return _oop_handle_list != nullptr; } }; inline JavaThread* JavaThread::current_or_null() { Thread* current = Thread::current_or_null(); return current != nullptr ? JavaThread::cast(current) : nullptr; } class UnlockFlagSaver { private: JavaThread* _thread; bool _do_not_unlock; public: UnlockFlagSaver(JavaThread* t) { _thread = t; _do_not_unlock = t->do_not_unlock_if_synchronized(); t->set_do_not_unlock_if_synchronized(false); } ~UnlockFlagSaver() { _thread->set_do_not_unlock_if_synchronized(_do_not_unlock); } }; class JNIHandleMark : public StackObj { JavaThread* _thread; public: JNIHandleMark(JavaThread* thread) : _thread(thread) { thread->push_jni_handle_block(); } ~JNIHandleMark() { _thread->pop_jni_handle_block(); } }; class NoPreemptMark { ContinuationEntry* _ce; bool _unpin; public: NoPreemptMark(JavaThread* thread) : _ce(thread->last_continuation()), _unpin(false) { if (_ce != nullptr) _unpin = _ce->pin(); } ~NoPreemptMark() { if (_unpin) _ce->unpin(); } }; class ThreadOnMonitorWaitedEvent { JavaThread* _thread; public: ThreadOnMonitorWaitedEvent(JavaThread* thread) : _thread(thread) { JVMTI_ONLY(_thread->set_on_monitor_waited_event(true);) } ~ThreadOnMonitorWaitedEvent() { JVMTI_ONLY(_thread->set_on_monitor_waited_event(false);) } }; class ThreadInClassInitializer : public StackObj { JavaThread* _thread; InstanceKlass* _previous; public: ThreadInClassInitializer(JavaThread* thread, InstanceKlass* ik) : _thread(thread) { _previous = _thread->class_being_initialized(); _thread->set_class_being_initialized(ik); } ~ThreadInClassInitializer() { _thread->set_class_being_initialized(_previous); } }; #endif // SHARE_RUNTIME_JAVATHREAD_HPP