--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/src/hotspot/share/services/threadService.cpp Tue Sep 12 19:03:39 2017 +0200
@@ -0,0 +1,973 @@
+/*
+ * Copyright (c) 2003, 2017, 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.
+ *
+ */
+
+#include "precompiled.hpp"
+#include "classfile/systemDictionary.hpp"
+#include "memory/allocation.hpp"
+#include "memory/heapInspection.hpp"
+#include "memory/oopFactory.hpp"
+#include "memory/resourceArea.hpp"
+#include "oops/instanceKlass.hpp"
+#include "oops/objArrayOop.inline.hpp"
+#include "oops/oop.inline.hpp"
+#include "runtime/atomic.hpp"
+#include "runtime/handles.inline.hpp"
+#include "runtime/init.hpp"
+#include "runtime/thread.hpp"
+#include "runtime/vframe.hpp"
+#include "runtime/thread.inline.hpp"
+#include "runtime/vmThread.hpp"
+#include "runtime/vm_operations.hpp"
+#include "services/threadService.hpp"
+
+// TODO: we need to define a naming convention for perf counters
+// to distinguish counters for:
+// - standard JSR174 use
+// - Hotspot extension (public and committed)
+// - Hotspot extension (private/internal and uncommitted)
+
+// Default is disabled.
+bool ThreadService::_thread_monitoring_contention_enabled = false;
+bool ThreadService::_thread_cpu_time_enabled = false;
+bool ThreadService::_thread_allocated_memory_enabled = false;
+
+PerfCounter* ThreadService::_total_threads_count = NULL;
+PerfVariable* ThreadService::_live_threads_count = NULL;
+PerfVariable* ThreadService::_peak_threads_count = NULL;
+PerfVariable* ThreadService::_daemon_threads_count = NULL;
+volatile int ThreadService::_exiting_threads_count = 0;
+volatile int ThreadService::_exiting_daemon_threads_count = 0;
+
+ThreadDumpResult* ThreadService::_threaddump_list = NULL;
+
+static const int INITIAL_ARRAY_SIZE = 10;
+
+void ThreadService::init() {
+ EXCEPTION_MARK;
+
+ // These counters are for java.lang.management API support.
+ // They are created even if -XX:-UsePerfData is set and in
+ // that case, they will be allocated on C heap.
+
+ _total_threads_count =
+ PerfDataManager::create_counter(JAVA_THREADS, "started",
+ PerfData::U_Events, CHECK);
+
+ _live_threads_count =
+ PerfDataManager::create_variable(JAVA_THREADS, "live",
+ PerfData::U_None, CHECK);
+
+ _peak_threads_count =
+ PerfDataManager::create_variable(JAVA_THREADS, "livePeak",
+ PerfData::U_None, CHECK);
+
+ _daemon_threads_count =
+ PerfDataManager::create_variable(JAVA_THREADS, "daemon",
+ PerfData::U_None, CHECK);
+
+ if (os::is_thread_cpu_time_supported()) {
+ _thread_cpu_time_enabled = true;
+ }
+
+ _thread_allocated_memory_enabled = true; // Always on, so enable it
+}
+
+void ThreadService::reset_peak_thread_count() {
+ // Acquire the lock to update the peak thread count
+ // to synchronize with thread addition and removal.
+ MutexLockerEx mu(Threads_lock);
+ _peak_threads_count->set_value(get_live_thread_count());
+}
+
+void ThreadService::add_thread(JavaThread* thread, bool daemon) {
+ // Do not count VM internal or JVMTI agent threads
+ if (thread->is_hidden_from_external_view() ||
+ thread->is_jvmti_agent_thread()) {
+ return;
+ }
+
+ _total_threads_count->inc();
+ _live_threads_count->inc();
+
+ if (_live_threads_count->get_value() > _peak_threads_count->get_value()) {
+ _peak_threads_count->set_value(_live_threads_count->get_value());
+ }
+
+ if (daemon) {
+ _daemon_threads_count->inc();
+ }
+}
+
+void ThreadService::remove_thread(JavaThread* thread, bool daemon) {
+ Atomic::dec((jint*) &_exiting_threads_count);
+
+ if (thread->is_hidden_from_external_view() ||
+ thread->is_jvmti_agent_thread()) {
+ return;
+ }
+
+ _live_threads_count->set_value(_live_threads_count->get_value() - 1);
+
+ if (daemon) {
+ _daemon_threads_count->set_value(_daemon_threads_count->get_value() - 1);
+ Atomic::dec((jint*) &_exiting_daemon_threads_count);
+ }
+}
+
+void ThreadService::current_thread_exiting(JavaThread* jt) {
+ assert(jt == JavaThread::current(), "Called by current thread");
+ Atomic::inc((jint*) &_exiting_threads_count);
+
+ oop threadObj = jt->threadObj();
+ if (threadObj != NULL && java_lang_Thread::is_daemon(threadObj)) {
+ Atomic::inc((jint*) &_exiting_daemon_threads_count);
+ }
+}
+
+// FIXME: JVMTI should call this function
+Handle ThreadService::get_current_contended_monitor(JavaThread* thread) {
+ assert(thread != NULL, "should be non-NULL");
+ assert(Threads_lock->owned_by_self(), "must grab Threads_lock or be at safepoint");
+
+ ObjectMonitor *wait_obj = thread->current_waiting_monitor();
+
+ oop obj = NULL;
+ if (wait_obj != NULL) {
+ // thread is doing an Object.wait() call
+ obj = (oop) wait_obj->object();
+ assert(obj != NULL, "Object.wait() should have an object");
+ } else {
+ ObjectMonitor *enter_obj = thread->current_pending_monitor();
+ if (enter_obj != NULL) {
+ // thread is trying to enter() or raw_enter() an ObjectMonitor.
+ obj = (oop) enter_obj->object();
+ }
+ // If obj == NULL, then ObjectMonitor is raw which doesn't count.
+ }
+
+ Handle h(Thread::current(), obj);
+ return h;
+}
+
+bool ThreadService::set_thread_monitoring_contention(bool flag) {
+ MutexLocker m(Management_lock);
+
+ bool prev = _thread_monitoring_contention_enabled;
+ _thread_monitoring_contention_enabled = flag;
+
+ return prev;
+}
+
+bool ThreadService::set_thread_cpu_time_enabled(bool flag) {
+ MutexLocker m(Management_lock);
+
+ bool prev = _thread_cpu_time_enabled;
+ _thread_cpu_time_enabled = flag;
+
+ return prev;
+}
+
+bool ThreadService::set_thread_allocated_memory_enabled(bool flag) {
+ MutexLocker m(Management_lock);
+
+ bool prev = _thread_allocated_memory_enabled;
+ _thread_allocated_memory_enabled = flag;
+
+ return prev;
+}
+
+// GC support
+void ThreadService::oops_do(OopClosure* f) {
+ for (ThreadDumpResult* dump = _threaddump_list; dump != NULL; dump = dump->next()) {
+ dump->oops_do(f);
+ }
+}
+
+void ThreadService::metadata_do(void f(Metadata*)) {
+ for (ThreadDumpResult* dump = _threaddump_list; dump != NULL; dump = dump->next()) {
+ dump->metadata_do(f);
+ }
+}
+
+void ThreadService::add_thread_dump(ThreadDumpResult* dump) {
+ MutexLocker ml(Management_lock);
+ if (_threaddump_list == NULL) {
+ _threaddump_list = dump;
+ } else {
+ dump->set_next(_threaddump_list);
+ _threaddump_list = dump;
+ }
+}
+
+void ThreadService::remove_thread_dump(ThreadDumpResult* dump) {
+ MutexLocker ml(Management_lock);
+
+ ThreadDumpResult* prev = NULL;
+ bool found = false;
+ for (ThreadDumpResult* d = _threaddump_list; d != NULL; prev = d, d = d->next()) {
+ if (d == dump) {
+ if (prev == NULL) {
+ _threaddump_list = dump->next();
+ } else {
+ prev->set_next(dump->next());
+ }
+ found = true;
+ break;
+ }
+ }
+ assert(found, "The threaddump result to be removed must exist.");
+}
+
+// Dump stack trace of threads specified in the given threads array.
+// Returns StackTraceElement[][] each element is the stack trace of a thread in
+// the corresponding entry in the given threads array
+Handle ThreadService::dump_stack_traces(GrowableArray<instanceHandle>* threads,
+ int num_threads,
+ TRAPS) {
+ assert(num_threads > 0, "just checking");
+
+ ThreadDumpResult dump_result;
+ VM_ThreadDump op(&dump_result,
+ threads,
+ num_threads,
+ -1, /* entire stack */
+ false, /* with locked monitors */
+ false /* with locked synchronizers */);
+ VMThread::execute(&op);
+
+ // Allocate the resulting StackTraceElement[][] object
+
+ ResourceMark rm(THREAD);
+ Klass* k = SystemDictionary::resolve_or_fail(vmSymbols::java_lang_StackTraceElement_array(), true, CHECK_NH);
+ ObjArrayKlass* ik = ObjArrayKlass::cast(k);
+ objArrayOop r = oopFactory::new_objArray(ik, num_threads, CHECK_NH);
+ objArrayHandle result_obj(THREAD, r);
+
+ int num_snapshots = dump_result.num_snapshots();
+ assert(num_snapshots == num_threads, "Must have num_threads thread snapshots");
+ int i = 0;
+ for (ThreadSnapshot* ts = dump_result.snapshots(); ts != NULL; i++, ts = ts->next()) {
+ ThreadStackTrace* stacktrace = ts->get_stack_trace();
+ if (stacktrace == NULL) {
+ // No stack trace
+ result_obj->obj_at_put(i, NULL);
+ } else {
+ // Construct an array of java/lang/StackTraceElement object
+ Handle backtrace_h = stacktrace->allocate_fill_stack_trace_element_array(CHECK_NH);
+ result_obj->obj_at_put(i, backtrace_h());
+ }
+ }
+
+ return result_obj;
+}
+
+void ThreadService::reset_contention_count_stat(JavaThread* thread) {
+ ThreadStatistics* stat = thread->get_thread_stat();
+ if (stat != NULL) {
+ stat->reset_count_stat();
+ }
+}
+
+void ThreadService::reset_contention_time_stat(JavaThread* thread) {
+ ThreadStatistics* stat = thread->get_thread_stat();
+ if (stat != NULL) {
+ stat->reset_time_stat();
+ }
+}
+
+// Find deadlocks involving object monitors and concurrent locks if concurrent_locks is true
+DeadlockCycle* ThreadService::find_deadlocks_at_safepoint(bool concurrent_locks) {
+ // This code was modified from the original Threads::find_deadlocks code.
+ int globalDfn = 0, thisDfn;
+ ObjectMonitor* waitingToLockMonitor = NULL;
+ oop waitingToLockBlocker = NULL;
+ bool blocked_on_monitor = false;
+ JavaThread *currentThread, *previousThread;
+ int num_deadlocks = 0;
+
+ for (JavaThread* p = Threads::first(); p != NULL; p = p->next()) {
+ // Initialize the depth-first-number
+ p->set_depth_first_number(-1);
+ }
+
+ DeadlockCycle* deadlocks = NULL;
+ DeadlockCycle* last = NULL;
+ DeadlockCycle* cycle = new DeadlockCycle();
+ for (JavaThread* jt = Threads::first(); jt != NULL; jt = jt->next()) {
+ if (jt->depth_first_number() >= 0) {
+ // this thread was already visited
+ continue;
+ }
+
+ thisDfn = globalDfn;
+ jt->set_depth_first_number(globalDfn++);
+ previousThread = jt;
+ currentThread = jt;
+
+ cycle->reset();
+
+ // When there is a deadlock, all the monitors involved in the dependency
+ // cycle must be contended and heavyweight. So we only care about the
+ // heavyweight monitor a thread is waiting to lock.
+ waitingToLockMonitor = (ObjectMonitor*)jt->current_pending_monitor();
+ if (concurrent_locks) {
+ waitingToLockBlocker = jt->current_park_blocker();
+ }
+ while (waitingToLockMonitor != NULL || waitingToLockBlocker != NULL) {
+ cycle->add_thread(currentThread);
+ if (waitingToLockMonitor != NULL) {
+ address currentOwner = (address)waitingToLockMonitor->owner();
+ if (currentOwner != NULL) {
+ currentThread = Threads::owning_thread_from_monitor_owner(
+ currentOwner,
+ false /* no locking needed */);
+ if (currentThread == NULL) {
+ // This function is called at a safepoint so the JavaThread
+ // that owns waitingToLockMonitor should be findable, but
+ // if it is not findable, then the previous currentThread is
+ // blocked permanently. We record this as a deadlock.
+ num_deadlocks++;
+
+ cycle->set_deadlock(true);
+
+ // add this cycle to the deadlocks list
+ if (deadlocks == NULL) {
+ deadlocks = cycle;
+ } else {
+ last->set_next(cycle);
+ }
+ last = cycle;
+ cycle = new DeadlockCycle();
+ break;
+ }
+ }
+ } else {
+ if (concurrent_locks) {
+ if (waitingToLockBlocker->is_a(SystemDictionary::abstract_ownable_synchronizer_klass())) {
+ oop threadObj = java_util_concurrent_locks_AbstractOwnableSynchronizer::get_owner_threadObj(waitingToLockBlocker);
+ currentThread = threadObj != NULL ? java_lang_Thread::thread(threadObj) : NULL;
+ } else {
+ currentThread = NULL;
+ }
+ }
+ }
+
+ if (currentThread == NULL) {
+ // No dependency on another thread
+ break;
+ }
+ if (currentThread->depth_first_number() < 0) {
+ // First visit to this thread
+ currentThread->set_depth_first_number(globalDfn++);
+ } else if (currentThread->depth_first_number() < thisDfn) {
+ // Thread already visited, and not on a (new) cycle
+ break;
+ } else if (currentThread == previousThread) {
+ // Self-loop, ignore
+ break;
+ } else {
+ // We have a (new) cycle
+ num_deadlocks++;
+
+ cycle->set_deadlock(true);
+
+ // add this cycle to the deadlocks list
+ if (deadlocks == NULL) {
+ deadlocks = cycle;
+ } else {
+ last->set_next(cycle);
+ }
+ last = cycle;
+ cycle = new DeadlockCycle();
+ break;
+ }
+ previousThread = currentThread;
+ waitingToLockMonitor = (ObjectMonitor*)currentThread->current_pending_monitor();
+ if (concurrent_locks) {
+ waitingToLockBlocker = currentThread->current_park_blocker();
+ }
+ }
+
+ }
+ delete cycle;
+ return deadlocks;
+}
+
+ThreadDumpResult::ThreadDumpResult() : _num_threads(0), _num_snapshots(0), _snapshots(NULL), _next(NULL), _last(NULL) {
+
+ // Create a new ThreadDumpResult object and append to the list.
+ // If GC happens before this function returns, Method*
+ // in the stack trace will be visited.
+ ThreadService::add_thread_dump(this);
+}
+
+ThreadDumpResult::ThreadDumpResult(int num_threads) : _num_threads(num_threads), _num_snapshots(0), _snapshots(NULL), _next(NULL), _last(NULL) {
+ // Create a new ThreadDumpResult object and append to the list.
+ // If GC happens before this function returns, oops
+ // will be visited.
+ ThreadService::add_thread_dump(this);
+}
+
+ThreadDumpResult::~ThreadDumpResult() {
+ ThreadService::remove_thread_dump(this);
+
+ // free all the ThreadSnapshot objects created during
+ // the VM_ThreadDump operation
+ ThreadSnapshot* ts = _snapshots;
+ while (ts != NULL) {
+ ThreadSnapshot* p = ts;
+ ts = ts->next();
+ delete p;
+ }
+}
+
+
+void ThreadDumpResult::add_thread_snapshot(ThreadSnapshot* ts) {
+ assert(_num_threads == 0 || _num_snapshots < _num_threads,
+ "_num_snapshots must be less than _num_threads");
+ _num_snapshots++;
+ if (_snapshots == NULL) {
+ _snapshots = ts;
+ } else {
+ _last->set_next(ts);
+ }
+ _last = ts;
+}
+
+void ThreadDumpResult::oops_do(OopClosure* f) {
+ for (ThreadSnapshot* ts = _snapshots; ts != NULL; ts = ts->next()) {
+ ts->oops_do(f);
+ }
+}
+
+void ThreadDumpResult::metadata_do(void f(Metadata*)) {
+ for (ThreadSnapshot* ts = _snapshots; ts != NULL; ts = ts->next()) {
+ ts->metadata_do(f);
+ }
+}
+
+StackFrameInfo::StackFrameInfo(javaVFrame* jvf, bool with_lock_info) {
+ _method = jvf->method();
+ _bci = jvf->bci();
+ _class_holder = _method->method_holder()->klass_holder();
+ _locked_monitors = NULL;
+ if (with_lock_info) {
+ ResourceMark rm;
+ GrowableArray<MonitorInfo*>* list = jvf->locked_monitors();
+ int length = list->length();
+ if (length > 0) {
+ _locked_monitors = new (ResourceObj::C_HEAP, mtInternal) GrowableArray<oop>(length, true);
+ for (int i = 0; i < length; i++) {
+ MonitorInfo* monitor = list->at(i);
+ assert(monitor->owner(), "This monitor must have an owning object");
+ _locked_monitors->append(monitor->owner());
+ }
+ }
+ }
+}
+
+void StackFrameInfo::oops_do(OopClosure* f) {
+ if (_locked_monitors != NULL) {
+ int length = _locked_monitors->length();
+ for (int i = 0; i < length; i++) {
+ f->do_oop((oop*) _locked_monitors->adr_at(i));
+ }
+ }
+ f->do_oop(&_class_holder);
+}
+
+void StackFrameInfo::metadata_do(void f(Metadata*)) {
+ f(_method);
+}
+
+void StackFrameInfo::print_on(outputStream* st) const {
+ ResourceMark rm;
+ java_lang_Throwable::print_stack_element(st, method(), bci());
+ int len = (_locked_monitors != NULL ? _locked_monitors->length() : 0);
+ for (int i = 0; i < len; i++) {
+ oop o = _locked_monitors->at(i);
+ st->print_cr("\t- locked <" INTPTR_FORMAT "> (a %s)", p2i(o), o->klass()->external_name());
+ }
+
+}
+
+// Iterate through monitor cache to find JNI locked monitors
+class InflatedMonitorsClosure: public MonitorClosure {
+private:
+ ThreadStackTrace* _stack_trace;
+ Thread* _thread;
+public:
+ InflatedMonitorsClosure(Thread* t, ThreadStackTrace* st) {
+ _thread = t;
+ _stack_trace = st;
+ }
+ void do_monitor(ObjectMonitor* mid) {
+ if (mid->owner() == _thread) {
+ oop object = (oop) mid->object();
+ if (!_stack_trace->is_owned_monitor_on_stack(object)) {
+ _stack_trace->add_jni_locked_monitor(object);
+ }
+ }
+ }
+};
+
+ThreadStackTrace::ThreadStackTrace(JavaThread* t, bool with_locked_monitors) {
+ _thread = t;
+ _frames = new (ResourceObj::C_HEAP, mtInternal) GrowableArray<StackFrameInfo*>(INITIAL_ARRAY_SIZE, true);
+ _depth = 0;
+ _with_locked_monitors = with_locked_monitors;
+ if (_with_locked_monitors) {
+ _jni_locked_monitors = new (ResourceObj::C_HEAP, mtInternal) GrowableArray<oop>(INITIAL_ARRAY_SIZE, true);
+ } else {
+ _jni_locked_monitors = NULL;
+ }
+}
+
+ThreadStackTrace::~ThreadStackTrace() {
+ for (int i = 0; i < _frames->length(); i++) {
+ delete _frames->at(i);
+ }
+ delete _frames;
+ if (_jni_locked_monitors != NULL) {
+ delete _jni_locked_monitors;
+ }
+}
+
+void ThreadStackTrace::dump_stack_at_safepoint(int maxDepth) {
+ assert(SafepointSynchronize::is_at_safepoint(), "all threads are stopped");
+
+ if (_thread->has_last_Java_frame()) {
+ RegisterMap reg_map(_thread);
+ vframe* start_vf = _thread->last_java_vframe(®_map);
+ int count = 0;
+ for (vframe* f = start_vf; f; f = f->sender() ) {
+ if (f->is_java_frame()) {
+ javaVFrame* jvf = javaVFrame::cast(f);
+ add_stack_frame(jvf);
+ count++;
+ } else {
+ // Ignore non-Java frames
+ }
+ if (maxDepth > 0 && count == maxDepth) {
+ // Skip frames if more than maxDepth
+ break;
+ }
+ }
+ }
+
+ if (_with_locked_monitors) {
+ // Iterate inflated monitors and find monitors locked by this thread
+ // not found in the stack
+ InflatedMonitorsClosure imc(_thread, this);
+ ObjectSynchronizer::monitors_iterate(&imc);
+ }
+}
+
+
+bool ThreadStackTrace::is_owned_monitor_on_stack(oop object) {
+ assert(SafepointSynchronize::is_at_safepoint(), "all threads are stopped");
+
+ bool found = false;
+ int num_frames = get_stack_depth();
+ for (int depth = 0; depth < num_frames; depth++) {
+ StackFrameInfo* frame = stack_frame_at(depth);
+ int len = frame->num_locked_monitors();
+ GrowableArray<oop>* locked_monitors = frame->locked_monitors();
+ for (int j = 0; j < len; j++) {
+ oop monitor = locked_monitors->at(j);
+ assert(monitor != NULL, "must be a Java object");
+ if (monitor == object) {
+ found = true;
+ break;
+ }
+ }
+ }
+ return found;
+}
+
+Handle ThreadStackTrace::allocate_fill_stack_trace_element_array(TRAPS) {
+ InstanceKlass* ik = SystemDictionary::StackTraceElement_klass();
+ assert(ik != NULL, "must be loaded in 1.4+");
+
+ // Allocate an array of java/lang/StackTraceElement object
+ objArrayOop ste = oopFactory::new_objArray(ik, _depth, CHECK_NH);
+ objArrayHandle backtrace(THREAD, ste);
+ for (int j = 0; j < _depth; j++) {
+ StackFrameInfo* frame = _frames->at(j);
+ methodHandle mh(THREAD, frame->method());
+ oop element = java_lang_StackTraceElement::create(mh, frame->bci(), CHECK_NH);
+ backtrace->obj_at_put(j, element);
+ }
+ return backtrace;
+}
+
+void ThreadStackTrace::add_stack_frame(javaVFrame* jvf) {
+ StackFrameInfo* frame = new StackFrameInfo(jvf, _with_locked_monitors);
+ _frames->append(frame);
+ _depth++;
+}
+
+void ThreadStackTrace::oops_do(OopClosure* f) {
+ int length = _frames->length();
+ for (int i = 0; i < length; i++) {
+ _frames->at(i)->oops_do(f);
+ }
+
+ length = (_jni_locked_monitors != NULL ? _jni_locked_monitors->length() : 0);
+ for (int j = 0; j < length; j++) {
+ f->do_oop((oop*) _jni_locked_monitors->adr_at(j));
+ }
+}
+
+void ThreadStackTrace::metadata_do(void f(Metadata*)) {
+ int length = _frames->length();
+ for (int i = 0; i < length; i++) {
+ _frames->at(i)->metadata_do(f);
+ }
+}
+
+
+ConcurrentLocksDump::~ConcurrentLocksDump() {
+ if (_retain_map_on_free) {
+ return;
+ }
+
+ for (ThreadConcurrentLocks* t = _map; t != NULL;) {
+ ThreadConcurrentLocks* tcl = t;
+ t = t->next();
+ delete tcl;
+ }
+}
+
+void ConcurrentLocksDump::dump_at_safepoint() {
+ // dump all locked concurrent locks
+ assert(SafepointSynchronize::is_at_safepoint(), "all threads are stopped");
+
+ ResourceMark rm;
+
+ GrowableArray<oop>* aos_objects = new GrowableArray<oop>(INITIAL_ARRAY_SIZE);
+
+ // Find all instances of AbstractOwnableSynchronizer
+ HeapInspection::find_instances_at_safepoint(SystemDictionary::abstract_ownable_synchronizer_klass(),
+ aos_objects);
+ // Build a map of thread to its owned AQS locks
+ build_map(aos_objects);
+}
+
+
+// build a map of JavaThread to all its owned AbstractOwnableSynchronizer
+void ConcurrentLocksDump::build_map(GrowableArray<oop>* aos_objects) {
+ int length = aos_objects->length();
+ for (int i = 0; i < length; i++) {
+ oop o = aos_objects->at(i);
+ oop owner_thread_obj = java_util_concurrent_locks_AbstractOwnableSynchronizer::get_owner_threadObj(o);
+ if (owner_thread_obj != NULL) {
+ JavaThread* thread = java_lang_Thread::thread(owner_thread_obj);
+ assert(o->is_instance(), "Must be an instanceOop");
+ add_lock(thread, (instanceOop) o);
+ }
+ }
+}
+
+void ConcurrentLocksDump::add_lock(JavaThread* thread, instanceOop o) {
+ ThreadConcurrentLocks* tcl = thread_concurrent_locks(thread);
+ if (tcl != NULL) {
+ tcl->add_lock(o);
+ return;
+ }
+
+ // First owned lock found for this thread
+ tcl = new ThreadConcurrentLocks(thread);
+ tcl->add_lock(o);
+ if (_map == NULL) {
+ _map = tcl;
+ } else {
+ _last->set_next(tcl);
+ }
+ _last = tcl;
+}
+
+ThreadConcurrentLocks* ConcurrentLocksDump::thread_concurrent_locks(JavaThread* thread) {
+ for (ThreadConcurrentLocks* tcl = _map; tcl != NULL; tcl = tcl->next()) {
+ if (tcl->java_thread() == thread) {
+ return tcl;
+ }
+ }
+ return NULL;
+}
+
+void ConcurrentLocksDump::print_locks_on(JavaThread* t, outputStream* st) {
+ st->print_cr(" Locked ownable synchronizers:");
+ ThreadConcurrentLocks* tcl = thread_concurrent_locks(t);
+ GrowableArray<instanceOop>* locks = (tcl != NULL ? tcl->owned_locks() : NULL);
+ if (locks == NULL || locks->is_empty()) {
+ st->print_cr("\t- None");
+ st->cr();
+ return;
+ }
+
+ for (int i = 0; i < locks->length(); i++) {
+ instanceOop obj = locks->at(i);
+ st->print_cr("\t- <" INTPTR_FORMAT "> (a %s)", p2i(obj), obj->klass()->external_name());
+ }
+ st->cr();
+}
+
+ThreadConcurrentLocks::ThreadConcurrentLocks(JavaThread* thread) {
+ _thread = thread;
+ _owned_locks = new (ResourceObj::C_HEAP, mtInternal) GrowableArray<instanceOop>(INITIAL_ARRAY_SIZE, true);
+ _next = NULL;
+}
+
+ThreadConcurrentLocks::~ThreadConcurrentLocks() {
+ delete _owned_locks;
+}
+
+void ThreadConcurrentLocks::add_lock(instanceOop o) {
+ _owned_locks->append(o);
+}
+
+void ThreadConcurrentLocks::oops_do(OopClosure* f) {
+ int length = _owned_locks->length();
+ for (int i = 0; i < length; i++) {
+ f->do_oop((oop*) _owned_locks->adr_at(i));
+ }
+}
+
+ThreadStatistics::ThreadStatistics() {
+ _contended_enter_count = 0;
+ _monitor_wait_count = 0;
+ _sleep_count = 0;
+ _count_pending_reset = false;
+ _timer_pending_reset = false;
+ memset((void*) _perf_recursion_counts, 0, sizeof(_perf_recursion_counts));
+}
+
+ThreadSnapshot::ThreadSnapshot(JavaThread* thread) {
+ _thread = thread;
+ _threadObj = thread->threadObj();
+ _stack_trace = NULL;
+ _concurrent_locks = NULL;
+ _next = NULL;
+
+ ThreadStatistics* stat = thread->get_thread_stat();
+ _contended_enter_ticks = stat->contended_enter_ticks();
+ _contended_enter_count = stat->contended_enter_count();
+ _monitor_wait_ticks = stat->monitor_wait_ticks();
+ _monitor_wait_count = stat->monitor_wait_count();
+ _sleep_ticks = stat->sleep_ticks();
+ _sleep_count = stat->sleep_count();
+
+ _blocker_object = NULL;
+ _blocker_object_owner = NULL;
+
+ _thread_status = java_lang_Thread::get_thread_status(_threadObj);
+ _is_ext_suspended = thread->is_being_ext_suspended();
+ _is_in_native = (thread->thread_state() == _thread_in_native);
+
+ if (_thread_status == java_lang_Thread::BLOCKED_ON_MONITOR_ENTER ||
+ _thread_status == java_lang_Thread::IN_OBJECT_WAIT ||
+ _thread_status == java_lang_Thread::IN_OBJECT_WAIT_TIMED) {
+
+ Handle obj = ThreadService::get_current_contended_monitor(thread);
+ if (obj() == NULL) {
+ // monitor no longer exists; thread is not blocked
+ _thread_status = java_lang_Thread::RUNNABLE;
+ } else {
+ _blocker_object = obj();
+ JavaThread* owner = ObjectSynchronizer::get_lock_owner(obj, false);
+ if ((owner == NULL && _thread_status == java_lang_Thread::BLOCKED_ON_MONITOR_ENTER)
+ || (owner != NULL && owner->is_attaching_via_jni())) {
+ // ownership information of the monitor is not available
+ // (may no longer be owned or releasing to some other thread)
+ // make this thread in RUNNABLE state.
+ // And when the owner thread is in attaching state, the java thread
+ // is not completely initialized. For example thread name and id
+ // and may not be set, so hide the attaching thread.
+ _thread_status = java_lang_Thread::RUNNABLE;
+ _blocker_object = NULL;
+ } else if (owner != NULL) {
+ _blocker_object_owner = owner->threadObj();
+ }
+ }
+ }
+
+ // Support for JSR-166 locks
+ if (JDK_Version::current().supports_thread_park_blocker() &&
+ (_thread_status == java_lang_Thread::PARKED ||
+ _thread_status == java_lang_Thread::PARKED_TIMED)) {
+
+ _blocker_object = thread->current_park_blocker();
+ if (_blocker_object != NULL && _blocker_object->is_a(SystemDictionary::abstract_ownable_synchronizer_klass())) {
+ _blocker_object_owner = java_util_concurrent_locks_AbstractOwnableSynchronizer::get_owner_threadObj(_blocker_object);
+ }
+ }
+}
+
+ThreadSnapshot::~ThreadSnapshot() {
+ delete _stack_trace;
+ delete _concurrent_locks;
+}
+
+void ThreadSnapshot::dump_stack_at_safepoint(int max_depth, bool with_locked_monitors) {
+ _stack_trace = new ThreadStackTrace(_thread, with_locked_monitors);
+ _stack_trace->dump_stack_at_safepoint(max_depth);
+}
+
+
+void ThreadSnapshot::oops_do(OopClosure* f) {
+ f->do_oop(&_threadObj);
+ f->do_oop(&_blocker_object);
+ f->do_oop(&_blocker_object_owner);
+ if (_stack_trace != NULL) {
+ _stack_trace->oops_do(f);
+ }
+ if (_concurrent_locks != NULL) {
+ _concurrent_locks->oops_do(f);
+ }
+}
+
+void ThreadSnapshot::metadata_do(void f(Metadata*)) {
+ if (_stack_trace != NULL) {
+ _stack_trace->metadata_do(f);
+ }
+}
+
+
+DeadlockCycle::DeadlockCycle() {
+ _is_deadlock = false;
+ _threads = new (ResourceObj::C_HEAP, mtInternal) GrowableArray<JavaThread*>(INITIAL_ARRAY_SIZE, true);
+ _next = NULL;
+}
+
+DeadlockCycle::~DeadlockCycle() {
+ delete _threads;
+}
+
+void DeadlockCycle::print_on(outputStream* st) const {
+ st->cr();
+ st->print_cr("Found one Java-level deadlock:");
+ st->print("=============================");
+
+ JavaThread* currentThread;
+ ObjectMonitor* waitingToLockMonitor;
+ oop waitingToLockBlocker;
+ int len = _threads->length();
+ for (int i = 0; i < len; i++) {
+ currentThread = _threads->at(i);
+ waitingToLockMonitor = (ObjectMonitor*)currentThread->current_pending_monitor();
+ waitingToLockBlocker = currentThread->current_park_blocker();
+ st->cr();
+ st->print_cr("\"%s\":", currentThread->get_thread_name());
+ const char* owner_desc = ",\n which is held by";
+ if (waitingToLockMonitor != NULL) {
+ st->print(" waiting to lock monitor " INTPTR_FORMAT, p2i(waitingToLockMonitor));
+ oop obj = (oop)waitingToLockMonitor->object();
+ if (obj != NULL) {
+ st->print(" (object " INTPTR_FORMAT ", a %s)", p2i(obj),
+ obj->klass()->external_name());
+
+ if (!currentThread->current_pending_monitor_is_from_java()) {
+ owner_desc = "\n in JNI, which is held by";
+ }
+ } else {
+ // No Java object associated - a JVMTI raw monitor
+ owner_desc = " (JVMTI raw monitor),\n which is held by";
+ }
+ currentThread = Threads::owning_thread_from_monitor_owner(
+ (address)waitingToLockMonitor->owner(),
+ false /* no locking needed */);
+ if (currentThread == NULL) {
+ // The deadlock was detected at a safepoint so the JavaThread
+ // that owns waitingToLockMonitor should be findable, but
+ // if it is not findable, then the previous currentThread is
+ // blocked permanently.
+ st->print("%s UNKNOWN_owner_addr=" PTR_FORMAT, owner_desc,
+ p2i(waitingToLockMonitor->owner()));
+ continue;
+ }
+ } else {
+ st->print(" waiting for ownable synchronizer " INTPTR_FORMAT ", (a %s)",
+ p2i(waitingToLockBlocker),
+ waitingToLockBlocker->klass()->external_name());
+ assert(waitingToLockBlocker->is_a(SystemDictionary::abstract_ownable_synchronizer_klass()),
+ "Must be an AbstractOwnableSynchronizer");
+ oop ownerObj = java_util_concurrent_locks_AbstractOwnableSynchronizer::get_owner_threadObj(waitingToLockBlocker);
+ currentThread = java_lang_Thread::thread(ownerObj);
+ }
+ st->print("%s \"%s\"", owner_desc, currentThread->get_thread_name());
+ }
+
+ st->cr();
+ st->cr();
+
+ // Print stack traces
+ bool oldJavaMonitorsInStackTrace = JavaMonitorsInStackTrace;
+ JavaMonitorsInStackTrace = true;
+ st->print_cr("Java stack information for the threads listed above:");
+ st->print_cr("===================================================");
+ for (int j = 0; j < len; j++) {
+ currentThread = _threads->at(j);
+ st->print_cr("\"%s\":", currentThread->get_thread_name());
+ currentThread->print_stack_on(st);
+ }
+ JavaMonitorsInStackTrace = oldJavaMonitorsInStackTrace;
+}
+
+ThreadsListEnumerator::ThreadsListEnumerator(Thread* cur_thread,
+ bool include_jvmti_agent_threads,
+ bool include_jni_attaching_threads) {
+ assert(cur_thread == Thread::current(), "Check current thread");
+
+ int init_size = ThreadService::get_live_thread_count();
+ _threads_array = new GrowableArray<instanceHandle>(init_size);
+
+ MutexLockerEx ml(Threads_lock);
+
+ for (JavaThread* jt = Threads::first(); jt != NULL; jt = jt->next()) {
+ // skips JavaThreads in the process of exiting
+ // and also skips VM internal JavaThreads
+ // Threads in _thread_new or _thread_new_trans state are included.
+ // i.e. threads have been started but not yet running.
+ if (jt->threadObj() == NULL ||
+ jt->is_exiting() ||
+ !java_lang_Thread::is_alive(jt->threadObj()) ||
+ jt->is_hidden_from_external_view()) {
+ continue;
+ }
+
+ // skip agent threads
+ if (!include_jvmti_agent_threads && jt->is_jvmti_agent_thread()) {
+ continue;
+ }
+
+ // skip jni threads in the process of attaching
+ if (!include_jni_attaching_threads && jt->is_attaching_via_jni()) {
+ continue;
+ }
+
+ instanceHandle h(cur_thread, (instanceOop) jt->threadObj());
+ _threads_array->append(h);
+ }
+}