| /* |
| * Copyright (c) 2003, 2013, Oracle and/or its affiliates. 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_VM_SERVICES_THREADSERVICE_HPP |
| #define SHARE_VM_SERVICES_THREADSERVICE_HPP |
| |
| #include "classfile/javaClasses.hpp" |
| #include "runtime/handles.hpp" |
| #include "runtime/init.hpp" |
| #include "runtime/jniHandles.hpp" |
| #include "runtime/objectMonitor.hpp" |
| #include "runtime/objectMonitor.inline.hpp" |
| #include "runtime/perfData.hpp" |
| #include "services/management.hpp" |
| #include "services/serviceUtil.hpp" |
| |
| class OopClosure; |
| class ThreadDumpResult; |
| class ThreadStackTrace; |
| class ThreadSnapshot; |
| class StackFrameInfo; |
| class ThreadConcurrentLocks; |
| class DeadlockCycle; |
| |
| // VM monitoring and management support for the thread and |
| // synchronization subsystem |
| // |
| // Thread contention monitoring is disabled by default. |
| // When enabled, the VM will begin measuring the accumulated |
| // elapsed time a thread blocked on synchronization. |
| // |
| class ThreadService : public AllStatic { |
| private: |
| // These counters could be moved to Threads class |
| static PerfCounter* _total_threads_count; |
| static PerfVariable* _live_threads_count; |
| static PerfVariable* _peak_threads_count; |
| static PerfVariable* _daemon_threads_count; |
| |
| // These 2 counters are atomically incremented once the thread is exiting. |
| // They will be atomically decremented when ThreadService::remove_thread is called. |
| static volatile int _exiting_threads_count; |
| static volatile int _exiting_daemon_threads_count; |
| |
| static bool _thread_monitoring_contention_enabled; |
| static bool _thread_cpu_time_enabled; |
| static bool _thread_allocated_memory_enabled; |
| |
| // Need to keep the list of thread dump result that |
| // keep references to Method* since thread dump can be |
| // requested by multiple threads concurrently. |
| static ThreadDumpResult* _threaddump_list; |
| |
| public: |
| static void init(); |
| static void add_thread(JavaThread* thread, bool daemon); |
| static void remove_thread(JavaThread* thread, bool daemon); |
| static void current_thread_exiting(JavaThread* jt); |
| |
| static bool set_thread_monitoring_contention(bool flag); |
| static bool is_thread_monitoring_contention() { return _thread_monitoring_contention_enabled; } |
| |
| static bool set_thread_cpu_time_enabled(bool flag); |
| static bool is_thread_cpu_time_enabled() { return _thread_cpu_time_enabled; } |
| |
| static bool set_thread_allocated_memory_enabled(bool flag); |
| static bool is_thread_allocated_memory_enabled() { return _thread_cpu_time_enabled; } |
| |
| static jlong get_total_thread_count() { return _total_threads_count->get_value(); } |
| static jlong get_peak_thread_count() { return _peak_threads_count->get_value(); } |
| static jlong get_live_thread_count() { return _live_threads_count->get_value() - _exiting_threads_count; } |
| static jlong get_daemon_thread_count() { return _daemon_threads_count->get_value() - _exiting_daemon_threads_count; } |
| |
| static int exiting_threads_count() { return _exiting_threads_count; } |
| static int exiting_daemon_threads_count() { return _exiting_daemon_threads_count; } |
| |
| // Support for thread dump |
| static void add_thread_dump(ThreadDumpResult* dump); |
| static void remove_thread_dump(ThreadDumpResult* dump); |
| |
| static Handle get_current_contended_monitor(JavaThread* thread); |
| |
| // This function is called by JVM_DumpThreads. |
| static Handle dump_stack_traces(GrowableArray<instanceHandle>* threads, |
| int num_threads, TRAPS); |
| |
| static void reset_peak_thread_count(); |
| static void reset_contention_count_stat(JavaThread* thread); |
| static void reset_contention_time_stat(JavaThread* thread); |
| |
| static DeadlockCycle* find_deadlocks_at_safepoint(bool object_monitors_only); |
| |
| // GC support |
| static void oops_do(OopClosure* f); |
| static void metadata_do(void f(Metadata*)); |
| }; |
| |
| // Per-thread Statistics for synchronization |
| class ThreadStatistics : public CHeapObj<mtInternal> { |
| private: |
| // The following contention statistics are only updated by |
| // the thread owning these statistics when contention occurs. |
| |
| jlong _contended_enter_count; |
| elapsedTimer _contended_enter_timer; |
| jlong _monitor_wait_count; |
| elapsedTimer _monitor_wait_timer; |
| jlong _sleep_count; |
| elapsedTimer _sleep_timer; |
| |
| |
| // These two reset flags are set to true when another thread |
| // requests to reset the statistics. The actual statistics |
| // are reset when the thread contention occurs and attempts |
| // to update the statistics. |
| bool _count_pending_reset; |
| bool _timer_pending_reset; |
| |
| // Keep accurate times for potentially recursive class operations |
| int _perf_recursion_counts[6]; |
| elapsedTimer _perf_timers[6]; |
| |
| // utility functions |
| void check_and_reset_count() { |
| if (!_count_pending_reset) return; |
| _contended_enter_count = 0; |
| _monitor_wait_count = 0; |
| _sleep_count = 0; |
| _count_pending_reset = 0; |
| } |
| void check_and_reset_timer() { |
| if (!_timer_pending_reset) return; |
| _contended_enter_timer.reset(); |
| _monitor_wait_timer.reset(); |
| _sleep_timer.reset(); |
| _timer_pending_reset = 0; |
| } |
| |
| public: |
| ThreadStatistics(); |
| |
| jlong contended_enter_count() { return (_count_pending_reset ? 0 : _contended_enter_count); } |
| jlong contended_enter_ticks() { return (_timer_pending_reset ? 0 : _contended_enter_timer.active_ticks()); } |
| jlong monitor_wait_count() { return (_count_pending_reset ? 0 : _monitor_wait_count); } |
| jlong monitor_wait_ticks() { return (_timer_pending_reset ? 0 : _monitor_wait_timer.active_ticks()); } |
| jlong sleep_count() { return (_count_pending_reset ? 0 : _sleep_count); } |
| jlong sleep_ticks() { return (_timer_pending_reset ? 0 : _sleep_timer.active_ticks()); } |
| |
| void monitor_wait() { check_and_reset_count(); _monitor_wait_count++; } |
| void monitor_wait_begin() { check_and_reset_timer(); _monitor_wait_timer.start(); } |
| void monitor_wait_end() { _monitor_wait_timer.stop(); check_and_reset_timer(); } |
| |
| void thread_sleep() { check_and_reset_count(); _sleep_count++; } |
| void thread_sleep_begin() { check_and_reset_timer(); _sleep_timer.start(); } |
| void thread_sleep_end() { _sleep_timer.stop(); check_and_reset_timer(); } |
| |
| void contended_enter() { check_and_reset_count(); _contended_enter_count++; } |
| void contended_enter_begin() { check_and_reset_timer(); _contended_enter_timer.start(); } |
| void contended_enter_end() { _contended_enter_timer.stop(); check_and_reset_timer(); } |
| |
| void reset_count_stat() { _count_pending_reset = true; } |
| void reset_time_stat() { _timer_pending_reset = true; } |
| |
| int* perf_recursion_counts_addr() { return _perf_recursion_counts; } |
| elapsedTimer* perf_timers_addr() { return _perf_timers; } |
| }; |
| |
| // Thread snapshot to represent the thread state and statistics |
| class ThreadSnapshot : public CHeapObj<mtInternal> { |
| private: |
| JavaThread* _thread; |
| oop _threadObj; |
| java_lang_Thread::ThreadStatus _thread_status; |
| |
| bool _is_ext_suspended; |
| bool _is_in_native; |
| |
| jlong _contended_enter_ticks; |
| jlong _contended_enter_count; |
| jlong _monitor_wait_ticks; |
| jlong _monitor_wait_count; |
| jlong _sleep_ticks; |
| jlong _sleep_count; |
| oop _blocker_object; |
| oop _blocker_object_owner; |
| |
| ThreadStackTrace* _stack_trace; |
| ThreadConcurrentLocks* _concurrent_locks; |
| ThreadSnapshot* _next; |
| |
| public: |
| // Dummy snapshot |
| ThreadSnapshot() : _thread(NULL), _threadObj(NULL), _stack_trace(NULL), _concurrent_locks(NULL), _next(NULL), |
| _blocker_object(NULL), _blocker_object_owner(NULL) {}; |
| ThreadSnapshot(JavaThread* thread); |
| ~ThreadSnapshot(); |
| |
| java_lang_Thread::ThreadStatus thread_status() { return _thread_status; } |
| |
| oop threadObj() const { return _threadObj; } |
| |
| void set_next(ThreadSnapshot* n) { _next = n; } |
| |
| bool is_ext_suspended() { return _is_ext_suspended; } |
| bool is_in_native() { return _is_in_native; } |
| |
| jlong contended_enter_count() { return _contended_enter_count; } |
| jlong contended_enter_ticks() { return _contended_enter_ticks; } |
| jlong monitor_wait_count() { return _monitor_wait_count; } |
| jlong monitor_wait_ticks() { return _monitor_wait_ticks; } |
| jlong sleep_count() { return _sleep_count; } |
| jlong sleep_ticks() { return _sleep_ticks; } |
| |
| |
| oop blocker_object() { return _blocker_object; } |
| oop blocker_object_owner() { return _blocker_object_owner; } |
| |
| ThreadSnapshot* next() const { return _next; } |
| ThreadStackTrace* get_stack_trace() { return _stack_trace; } |
| ThreadConcurrentLocks* get_concurrent_locks() { return _concurrent_locks; } |
| |
| void dump_stack_at_safepoint(int max_depth, bool with_locked_monitors); |
| void set_concurrent_locks(ThreadConcurrentLocks* l) { _concurrent_locks = l; } |
| void oops_do(OopClosure* f); |
| void metadata_do(void f(Metadata*)); |
| }; |
| |
| class ThreadStackTrace : public CHeapObj<mtInternal> { |
| private: |
| JavaThread* _thread; |
| int _depth; // number of stack frames added |
| bool _with_locked_monitors; |
| GrowableArray<StackFrameInfo*>* _frames; |
| GrowableArray<oop>* _jni_locked_monitors; |
| |
| public: |
| |
| ThreadStackTrace(JavaThread* thread, bool with_locked_monitors); |
| ~ThreadStackTrace(); |
| |
| JavaThread* thread() { return _thread; } |
| StackFrameInfo* stack_frame_at(int i) { return _frames->at(i); } |
| int get_stack_depth() { return _depth; } |
| |
| void add_stack_frame(javaVFrame* jvf); |
| void dump_stack_at_safepoint(int max_depth); |
| Handle allocate_fill_stack_trace_element_array(TRAPS); |
| void oops_do(OopClosure* f); |
| void metadata_do(void f(Metadata*)); |
| GrowableArray<oop>* jni_locked_monitors() { return _jni_locked_monitors; } |
| int num_jni_locked_monitors() { return (_jni_locked_monitors != NULL ? _jni_locked_monitors->length() : 0); } |
| |
| bool is_owned_monitor_on_stack(oop object); |
| void add_jni_locked_monitor(oop object) { _jni_locked_monitors->append(object); } |
| }; |
| |
| // StackFrameInfo for keeping Method* and bci during |
| // stack walking for later construction of StackTraceElement[] |
| // Java instances |
| class StackFrameInfo : public CHeapObj<mtInternal> { |
| private: |
| Method* _method; |
| int _bci; |
| GrowableArray<oop>* _locked_monitors; // list of object monitors locked by this frame |
| // We need to save the mirrors in the backtrace to keep the class |
| // from being unloaded while we still have this stack trace. |
| oop _class_holder; |
| |
| public: |
| |
| StackFrameInfo(javaVFrame* jvf, bool with_locked_monitors); |
| ~StackFrameInfo() { |
| if (_locked_monitors != NULL) { |
| delete _locked_monitors; |
| } |
| }; |
| Method* method() const { return _method; } |
| int bci() const { return _bci; } |
| void oops_do(OopClosure* f); |
| void metadata_do(void f(Metadata*)); |
| |
| int num_locked_monitors() { return (_locked_monitors != NULL ? _locked_monitors->length() : 0); } |
| GrowableArray<oop>* locked_monitors() { return _locked_monitors; } |
| |
| void print_on(outputStream* st) const; |
| }; |
| |
| class ThreadConcurrentLocks : public CHeapObj<mtInternal> { |
| private: |
| GrowableArray<instanceOop>* _owned_locks; |
| ThreadConcurrentLocks* _next; |
| JavaThread* _thread; |
| public: |
| ThreadConcurrentLocks(JavaThread* thread); |
| ~ThreadConcurrentLocks(); |
| |
| void add_lock(instanceOop o); |
| void set_next(ThreadConcurrentLocks* n) { _next = n; } |
| ThreadConcurrentLocks* next() { return _next; } |
| JavaThread* java_thread() { return _thread; } |
| GrowableArray<instanceOop>* owned_locks() { return _owned_locks; } |
| void oops_do(OopClosure* f); |
| }; |
| |
| class ConcurrentLocksDump : public StackObj { |
| private: |
| ThreadConcurrentLocks* _map; |
| ThreadConcurrentLocks* _last; // Last ThreadConcurrentLocks in the map |
| bool _retain_map_on_free; |
| |
| void build_map(GrowableArray<oop>* aos_objects); |
| void add_lock(JavaThread* thread, instanceOop o); |
| |
| public: |
| ConcurrentLocksDump(bool retain_map_on_free) : _map(NULL), _last(NULL), _retain_map_on_free(retain_map_on_free) {}; |
| ConcurrentLocksDump() : _map(NULL), _last(NULL), _retain_map_on_free(false) {}; |
| ~ConcurrentLocksDump(); |
| |
| void dump_at_safepoint(); |
| ThreadConcurrentLocks* thread_concurrent_locks(JavaThread* thread); |
| void print_locks_on(JavaThread* t, outputStream* st); |
| }; |
| |
| class ThreadDumpResult : public StackObj { |
| private: |
| int _num_threads; |
| int _num_snapshots; |
| ThreadSnapshot* _snapshots; |
| ThreadSnapshot* _last; |
| ThreadDumpResult* _next; |
| public: |
| ThreadDumpResult(); |
| ThreadDumpResult(int num_threads); |
| ~ThreadDumpResult(); |
| |
| void add_thread_snapshot(ThreadSnapshot* ts); |
| void set_next(ThreadDumpResult* next) { _next = next; } |
| ThreadDumpResult* next() { return _next; } |
| int num_threads() { return _num_threads; } |
| int num_snapshots() { return _num_snapshots; } |
| ThreadSnapshot* snapshots() { return _snapshots; } |
| void oops_do(OopClosure* f); |
| void metadata_do(void f(Metadata*)); |
| }; |
| |
| class DeadlockCycle : public CHeapObj<mtInternal> { |
| private: |
| bool _is_deadlock; |
| GrowableArray<JavaThread*>* _threads; |
| DeadlockCycle* _next; |
| public: |
| DeadlockCycle(); |
| ~DeadlockCycle(); |
| |
| DeadlockCycle* next() { return _next; } |
| void set_next(DeadlockCycle* d) { _next = d; } |
| void add_thread(JavaThread* t) { _threads->append(t); } |
| void reset() { _is_deadlock = false; _threads->clear(); } |
| void set_deadlock(bool value) { _is_deadlock = value; } |
| bool is_deadlock() { return _is_deadlock; } |
| int num_threads() { return _threads->length(); } |
| GrowableArray<JavaThread*>* threads() { return _threads; } |
| void print_on(outputStream* st) const; |
| }; |
| |
| // Utility class to get list of java threads. |
| class ThreadsListEnumerator : public StackObj { |
| private: |
| GrowableArray<instanceHandle>* _threads_array; |
| public: |
| ThreadsListEnumerator(Thread* cur_thread, |
| bool include_jvmti_agent_threads = false, |
| bool include_jni_attaching_threads = true); |
| int num_threads() { return _threads_array->length(); } |
| instanceHandle get_threadObj(int index) { return _threads_array->at(index); } |
| }; |
| |
| |
| // abstract utility class to set new thread states, and restore previous after the block exits |
| class JavaThreadStatusChanger : public StackObj { |
| private: |
| java_lang_Thread::ThreadStatus _old_state; |
| JavaThread* _java_thread; |
| bool _is_alive; |
| |
| void save_old_state(JavaThread* java_thread) { |
| _java_thread = java_thread; |
| _is_alive = is_alive(java_thread); |
| if (is_alive()) { |
| _old_state = java_lang_Thread::get_thread_status(_java_thread->threadObj()); |
| } |
| } |
| |
| public: |
| static void set_thread_status(JavaThread* java_thread, |
| java_lang_Thread::ThreadStatus state) { |
| java_lang_Thread::set_thread_status(java_thread->threadObj(), state); |
| } |
| |
| void set_thread_status(java_lang_Thread::ThreadStatus state) { |
| if (is_alive()) { |
| set_thread_status(_java_thread, state); |
| } |
| } |
| |
| JavaThreadStatusChanger(JavaThread* java_thread, |
| java_lang_Thread::ThreadStatus state) : _old_state(java_lang_Thread::NEW) { |
| save_old_state(java_thread); |
| set_thread_status(state); |
| } |
| |
| JavaThreadStatusChanger(JavaThread* java_thread) : _old_state(java_lang_Thread::NEW) { |
| save_old_state(java_thread); |
| } |
| |
| ~JavaThreadStatusChanger() { |
| set_thread_status(_old_state); |
| } |
| |
| static bool is_alive(JavaThread* java_thread) { |
| return java_thread != NULL && java_thread->threadObj() != NULL; |
| } |
| |
| bool is_alive() { |
| return _is_alive; |
| } |
| }; |
| |
| // Change status to waiting on an object (timed or indefinite) |
| class JavaThreadInObjectWaitState : public JavaThreadStatusChanger { |
| private: |
| ThreadStatistics* _stat; |
| bool _active; |
| |
| public: |
| JavaThreadInObjectWaitState(JavaThread *java_thread, bool timed) : |
| JavaThreadStatusChanger(java_thread, |
| timed ? java_lang_Thread::IN_OBJECT_WAIT_TIMED : java_lang_Thread::IN_OBJECT_WAIT) { |
| if (is_alive()) { |
| _stat = java_thread->get_thread_stat(); |
| _active = ThreadService::is_thread_monitoring_contention(); |
| _stat->monitor_wait(); |
| if (_active) { |
| _stat->monitor_wait_begin(); |
| } |
| } else { |
| _active = false; |
| } |
| } |
| |
| ~JavaThreadInObjectWaitState() { |
| if (_active) { |
| _stat->monitor_wait_end(); |
| } |
| } |
| }; |
| |
| // Change status to parked (timed or indefinite) |
| class JavaThreadParkedState : public JavaThreadStatusChanger { |
| private: |
| ThreadStatistics* _stat; |
| bool _active; |
| |
| public: |
| JavaThreadParkedState(JavaThread *java_thread, bool timed) : |
| JavaThreadStatusChanger(java_thread, |
| timed ? java_lang_Thread::PARKED_TIMED : java_lang_Thread::PARKED) { |
| if (is_alive()) { |
| _stat = java_thread->get_thread_stat(); |
| _active = ThreadService::is_thread_monitoring_contention(); |
| _stat->monitor_wait(); |
| if (_active) { |
| _stat->monitor_wait_begin(); |
| } |
| } else { |
| _active = false; |
| } |
| } |
| |
| ~JavaThreadParkedState() { |
| if (_active) { |
| _stat->monitor_wait_end(); |
| } |
| } |
| }; |
| |
| // Change status to blocked on (re-)entering a synchronization block |
| class JavaThreadBlockedOnMonitorEnterState : public JavaThreadStatusChanger { |
| private: |
| ThreadStatistics* _stat; |
| bool _active; |
| |
| static bool contended_enter_begin(JavaThread *java_thread) { |
| set_thread_status(java_thread, java_lang_Thread::BLOCKED_ON_MONITOR_ENTER); |
| ThreadStatistics* stat = java_thread->get_thread_stat(); |
| stat->contended_enter(); |
| bool active = ThreadService::is_thread_monitoring_contention(); |
| if (active) { |
| stat->contended_enter_begin(); |
| } |
| return active; |
| } |
| |
| public: |
| // java_thread is waiting thread being blocked on monitor reenter. |
| // Current thread is the notifying thread which holds the monitor. |
| static bool wait_reenter_begin(JavaThread *java_thread, ObjectMonitor *obj_m) { |
| assert((java_thread != NULL), "Java thread should not be null here"); |
| bool active = false; |
| if (is_alive(java_thread) && ServiceUtil::visible_oop((oop)obj_m->object())) { |
| active = contended_enter_begin(java_thread); |
| } |
| return active; |
| } |
| |
| static void wait_reenter_end(JavaThread *java_thread, bool active) { |
| if (active) { |
| java_thread->get_thread_stat()->contended_enter_end(); |
| } |
| set_thread_status(java_thread, java_lang_Thread::RUNNABLE); |
| } |
| |
| JavaThreadBlockedOnMonitorEnterState(JavaThread *java_thread, ObjectMonitor *obj_m) : |
| _stat(NULL), _active(false), JavaThreadStatusChanger(java_thread) { |
| assert((java_thread != NULL), "Java thread should not be null here"); |
| // Change thread status and collect contended enter stats for monitor contended |
| // enter done for external java world objects and it is contended. All other cases |
| // like for vm internal objects and for external objects which are not contended |
| // thread status is not changed and contended enter stat is not collected. |
| _active = false; |
| if (is_alive() && ServiceUtil::visible_oop((oop)obj_m->object()) && obj_m->contentions() > 0) { |
| _stat = java_thread->get_thread_stat(); |
| _active = contended_enter_begin(java_thread); |
| } |
| } |
| |
| ~JavaThreadBlockedOnMonitorEnterState() { |
| if (_active) { |
| _stat->contended_enter_end(); |
| } |
| } |
| }; |
| |
| // Change status to sleeping |
| class JavaThreadSleepState : public JavaThreadStatusChanger { |
| private: |
| ThreadStatistics* _stat; |
| bool _active; |
| public: |
| JavaThreadSleepState(JavaThread *java_thread) : |
| JavaThreadStatusChanger(java_thread, java_lang_Thread::SLEEPING) { |
| if (is_alive()) { |
| _stat = java_thread->get_thread_stat(); |
| _active = ThreadService::is_thread_monitoring_contention(); |
| _stat->thread_sleep(); |
| if (_active) { |
| _stat->thread_sleep_begin(); |
| } |
| } else { |
| _active = false; |
| } |
| } |
| |
| ~JavaThreadSleepState() { |
| if (_active) { |
| _stat->thread_sleep_end(); |
| } |
| } |
| }; |
| |
| #endif // SHARE_VM_SERVICES_THREADSERVICE_HPP |