--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/src/hotspot/share/runtime/vmOperations.cpp Thu Dec 06 15:44:40 2018 +0100
@@ -0,0 +1,508 @@
+/*
+ * Copyright (c) 1997, 2018, 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/symbolTable.hpp"
+#include "classfile/vmSymbols.hpp"
+#include "code/codeCache.hpp"
+#include "compiler/compileBroker.hpp"
+#include "gc/shared/isGCActiveMark.hpp"
+#include "logging/log.hpp"
+#include "logging/logStream.hpp"
+#include "memory/heapInspection.hpp"
+#include "memory/resourceArea.hpp"
+#include "oops/symbol.hpp"
+#include "runtime/arguments.hpp"
+#include "runtime/deoptimization.hpp"
+#include "runtime/frame.inline.hpp"
+#include "runtime/interfaceSupport.inline.hpp"
+#include "runtime/sweeper.hpp"
+#include "runtime/thread.inline.hpp"
+#include "runtime/threadSMR.inline.hpp"
+#include "runtime/vmOperations.hpp"
+#include "services/threadService.hpp"
+
+#define VM_OP_NAME_INITIALIZE(name) #name,
+
+const char* VM_Operation::_names[VM_Operation::VMOp_Terminating] = \
+ { VM_OPS_DO(VM_OP_NAME_INITIALIZE) };
+
+void VM_Operation::set_calling_thread(Thread* thread, ThreadPriority priority) {
+ _calling_thread = thread;
+ assert(MinPriority <= priority && priority <= MaxPriority, "sanity check");
+ _priority = priority;
+}
+
+
+void VM_Operation::evaluate() {
+ ResourceMark rm;
+ LogTarget(Debug, vmoperation) lt;
+ if (lt.is_enabled()) {
+ LogStream ls(lt);
+ ls.print("begin ");
+ print_on_error(&ls);
+ ls.cr();
+ }
+ doit();
+ if (lt.is_enabled()) {
+ LogStream ls(lt);
+ ls.print("end ");
+ print_on_error(&ls);
+ ls.cr();
+ }
+}
+
+const char* VM_Operation::mode_to_string(Mode mode) {
+ switch(mode) {
+ case _safepoint : return "safepoint";
+ case _no_safepoint : return "no safepoint";
+ case _concurrent : return "concurrent";
+ case _async_safepoint: return "async safepoint";
+ default : return "unknown";
+ }
+}
+// Called by fatal error handler.
+void VM_Operation::print_on_error(outputStream* st) const {
+ st->print("VM_Operation (" PTR_FORMAT "): ", p2i(this));
+ st->print("%s", name());
+
+ const char* mode = mode_to_string(evaluation_mode());
+ st->print(", mode: %s", mode);
+
+ if (calling_thread()) {
+ st->print(", requested by thread " PTR_FORMAT, p2i(calling_thread()));
+ }
+}
+
+void VM_ThreadStop::doit() {
+ assert(SafepointSynchronize::is_at_safepoint(), "must be at a safepoint");
+ ThreadsListHandle tlh;
+ JavaThread* target = java_lang_Thread::thread(target_thread());
+ // Note that this now allows multiple ThreadDeath exceptions to be
+ // thrown at a thread.
+ if (target != NULL && (!EnableThreadSMRExtraValidityChecks || tlh.includes(target))) {
+ // The target thread has run and has not exited yet.
+ target->send_thread_stop(throwable());
+ }
+}
+
+void VM_ClearICs::doit() {
+ if (_preserve_static_stubs) {
+ CodeCache::cleanup_inline_caches();
+ } else {
+ CodeCache::clear_inline_caches();
+ }
+}
+
+void VM_Deoptimize::doit() {
+ // We do not want any GCs to happen while we are in the middle of this VM operation
+ ResourceMark rm;
+ DeoptimizationMarker dm;
+
+ // Deoptimize all activations depending on marked nmethods
+ Deoptimization::deoptimize_dependents();
+
+ // Make the dependent methods not entrant
+ CodeCache::make_marked_nmethods_not_entrant();
+}
+
+void VM_MarkActiveNMethods::doit() {
+ NMethodSweeper::mark_active_nmethods();
+}
+
+VM_DeoptimizeFrame::VM_DeoptimizeFrame(JavaThread* thread, intptr_t* id, int reason) {
+ _thread = thread;
+ _id = id;
+ _reason = reason;
+}
+
+
+void VM_DeoptimizeFrame::doit() {
+ assert(_reason > Deoptimization::Reason_none && _reason < Deoptimization::Reason_LIMIT, "invalid deopt reason");
+ Deoptimization::deoptimize_frame_internal(_thread, _id, (Deoptimization::DeoptReason)_reason);
+}
+
+
+#ifndef PRODUCT
+
+void VM_DeoptimizeAll::doit() {
+ DeoptimizationMarker dm;
+ JavaThreadIteratorWithHandle jtiwh;
+ // deoptimize all java threads in the system
+ if (DeoptimizeALot) {
+ for (; JavaThread *thread = jtiwh.next(); ) {
+ if (thread->has_last_Java_frame()) {
+ thread->deoptimize();
+ }
+ }
+ } else if (DeoptimizeRandom) {
+
+ // Deoptimize some selected threads and frames
+ int tnum = os::random() & 0x3;
+ int fnum = os::random() & 0x3;
+ int tcount = 0;
+ for (; JavaThread *thread = jtiwh.next(); ) {
+ if (thread->has_last_Java_frame()) {
+ if (tcount++ == tnum) {
+ tcount = 0;
+ int fcount = 0;
+ // Deoptimize some selected frames.
+ // Biased llocking wants a updated register map
+ for(StackFrameStream fst(thread, UseBiasedLocking); !fst.is_done(); fst.next()) {
+ if (fst.current()->can_be_deoptimized()) {
+ if (fcount++ == fnum) {
+ fcount = 0;
+ Deoptimization::deoptimize(thread, *fst.current(), fst.register_map());
+ }
+ }
+ }
+ }
+ }
+ }
+ }
+}
+
+
+void VM_ZombieAll::doit() {
+ JavaThread *thread = (JavaThread *)calling_thread();
+ assert(thread->is_Java_thread(), "must be a Java thread");
+ thread->make_zombies();
+}
+
+#endif // !PRODUCT
+
+void VM_Verify::doit() {
+ Universe::heap()->prepare_for_verify();
+ Universe::verify();
+}
+
+bool VM_PrintThreads::doit_prologue() {
+ // Get Heap_lock if concurrent locks will be dumped
+ if (_print_concurrent_locks) {
+ Heap_lock->lock();
+ }
+ return true;
+}
+
+void VM_PrintThreads::doit() {
+ Threads::print_on(_out, true, false, _print_concurrent_locks, _print_extended_info);
+}
+
+void VM_PrintThreads::doit_epilogue() {
+ if (_print_concurrent_locks) {
+ // Release Heap_lock
+ Heap_lock->unlock();
+ }
+}
+
+void VM_PrintJNI::doit() {
+ JNIHandles::print_on(_out);
+}
+
+void VM_PrintMetadata::doit() {
+ MetaspaceUtils::print_report(_out, _scale, _flags);
+}
+
+VM_FindDeadlocks::~VM_FindDeadlocks() {
+ if (_deadlocks != NULL) {
+ DeadlockCycle* cycle = _deadlocks;
+ while (cycle != NULL) {
+ DeadlockCycle* d = cycle;
+ cycle = cycle->next();
+ delete d;
+ }
+ }
+}
+
+void VM_FindDeadlocks::doit() {
+ // Update the hazard ptr in the originating thread to the current
+ // list of threads. This VM operation needs the current list of
+ // threads for proper deadlock detection and those are the
+ // JavaThreads we need to be protected when we return info to the
+ // originating thread.
+ _setter.set();
+
+ _deadlocks = ThreadService::find_deadlocks_at_safepoint(_setter.list(), _concurrent_locks);
+ if (_out != NULL) {
+ int num_deadlocks = 0;
+ for (DeadlockCycle* cycle = _deadlocks; cycle != NULL; cycle = cycle->next()) {
+ num_deadlocks++;
+ cycle->print_on_with(_setter.list(), _out);
+ }
+
+ if (num_deadlocks == 1) {
+ _out->print_cr("\nFound 1 deadlock.\n");
+ _out->flush();
+ } else if (num_deadlocks > 1) {
+ _out->print_cr("\nFound %d deadlocks.\n", num_deadlocks);
+ _out->flush();
+ }
+ }
+}
+
+VM_ThreadDump::VM_ThreadDump(ThreadDumpResult* result,
+ int max_depth,
+ bool with_locked_monitors,
+ bool with_locked_synchronizers) {
+ _result = result;
+ _num_threads = 0; // 0 indicates all threads
+ _threads = NULL;
+ _result = result;
+ _max_depth = max_depth;
+ _with_locked_monitors = with_locked_monitors;
+ _with_locked_synchronizers = with_locked_synchronizers;
+}
+
+VM_ThreadDump::VM_ThreadDump(ThreadDumpResult* result,
+ GrowableArray<instanceHandle>* threads,
+ int num_threads,
+ int max_depth,
+ bool with_locked_monitors,
+ bool with_locked_synchronizers) {
+ _result = result;
+ _num_threads = num_threads;
+ _threads = threads;
+ _result = result;
+ _max_depth = max_depth;
+ _with_locked_monitors = with_locked_monitors;
+ _with_locked_synchronizers = with_locked_synchronizers;
+}
+
+bool VM_ThreadDump::doit_prologue() {
+ if (_with_locked_synchronizers) {
+ // Acquire Heap_lock to dump concurrent locks
+ Heap_lock->lock();
+ }
+
+ return true;
+}
+
+void VM_ThreadDump::doit_epilogue() {
+ if (_with_locked_synchronizers) {
+ // Release Heap_lock
+ Heap_lock->unlock();
+ }
+}
+
+void VM_ThreadDump::doit() {
+ ResourceMark rm;
+
+ // Set the hazard ptr in the originating thread to protect the
+ // current list of threads. This VM operation needs the current list
+ // of threads for a proper dump and those are the JavaThreads we need
+ // to be protected when we return info to the originating thread.
+ _result->set_t_list();
+
+ ConcurrentLocksDump concurrent_locks(true);
+ if (_with_locked_synchronizers) {
+ concurrent_locks.dump_at_safepoint();
+ }
+
+ if (_num_threads == 0) {
+ // Snapshot all live threads
+
+ for (uint i = 0; i < _result->t_list()->length(); i++) {
+ JavaThread* jt = _result->t_list()->thread_at(i);
+ if (jt->is_exiting() ||
+ jt->is_hidden_from_external_view()) {
+ // skip terminating threads and hidden threads
+ continue;
+ }
+ ThreadConcurrentLocks* tcl = NULL;
+ if (_with_locked_synchronizers) {
+ tcl = concurrent_locks.thread_concurrent_locks(jt);
+ }
+ ThreadSnapshot* ts = snapshot_thread(jt, tcl);
+ _result->add_thread_snapshot(ts);
+ }
+ } else {
+ // Snapshot threads in the given _threads array
+ // A dummy snapshot is created if a thread doesn't exist
+
+ for (int i = 0; i < _num_threads; i++) {
+ instanceHandle th = _threads->at(i);
+ if (th() == NULL) {
+ // skip if the thread doesn't exist
+ // Add a dummy snapshot
+ _result->add_thread_snapshot(new ThreadSnapshot());
+ continue;
+ }
+
+ // Dump thread stack only if the thread is alive and not exiting
+ // and not VM internal thread.
+ JavaThread* jt = java_lang_Thread::thread(th());
+ if (jt != NULL && !_result->t_list()->includes(jt)) {
+ // _threads[i] doesn't refer to a valid JavaThread; this check
+ // is primarily for JVM_DumpThreads() which doesn't have a good
+ // way to validate the _threads array.
+ jt = NULL;
+ }
+ if (jt == NULL || /* thread not alive */
+ jt->is_exiting() ||
+ jt->is_hidden_from_external_view()) {
+ // add a NULL snapshot if skipped
+ _result->add_thread_snapshot(new ThreadSnapshot());
+ continue;
+ }
+ ThreadConcurrentLocks* tcl = NULL;
+ if (_with_locked_synchronizers) {
+ tcl = concurrent_locks.thread_concurrent_locks(jt);
+ }
+ ThreadSnapshot* ts = snapshot_thread(jt, tcl);
+ _result->add_thread_snapshot(ts);
+ }
+ }
+}
+
+ThreadSnapshot* VM_ThreadDump::snapshot_thread(JavaThread* java_thread, ThreadConcurrentLocks* tcl) {
+ ThreadSnapshot* snapshot = new ThreadSnapshot(_result->t_list(), java_thread);
+ snapshot->dump_stack_at_safepoint(_max_depth, _with_locked_monitors);
+ snapshot->set_concurrent_locks(tcl);
+ return snapshot;
+}
+
+volatile bool VM_Exit::_vm_exited = false;
+Thread * volatile VM_Exit::_shutdown_thread = NULL;
+
+int VM_Exit::set_vm_exited() {
+
+ Thread * thr_cur = Thread::current();
+
+ assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint already");
+
+ int num_active = 0;
+
+ _shutdown_thread = thr_cur;
+ _vm_exited = true; // global flag
+ for (JavaThreadIteratorWithHandle jtiwh; JavaThread *thr = jtiwh.next(); ) {
+ if (thr!=thr_cur && thr->thread_state() == _thread_in_native) {
+ ++num_active;
+ thr->set_terminated(JavaThread::_vm_exited); // per-thread flag
+ }
+ }
+
+ return num_active;
+}
+
+int VM_Exit::wait_for_threads_in_native_to_block() {
+ // VM exits at safepoint. This function must be called at the final safepoint
+ // to wait for threads in _thread_in_native state to be quiescent.
+ assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint already");
+
+ Thread * thr_cur = Thread::current();
+ Monitor timer(Mutex::leaf, "VM_Exit timer", true,
+ Monitor::_safepoint_check_never);
+
+ // Compiler threads need longer wait because they can access VM data directly
+ // while in native. If they are active and some structures being used are
+ // deleted by the shutdown sequence, they will crash. On the other hand, user
+ // threads must go through native=>Java/VM transitions first to access VM
+ // data, and they will be stopped during state transition. In theory, we
+ // don't have to wait for user threads to be quiescent, but it's always
+ // better to terminate VM when current thread is the only active thread, so
+ // wait for user threads too. Numbers are in 10 milliseconds.
+ int max_wait_user_thread = 30; // at least 300 milliseconds
+ int max_wait_compiler_thread = 1000; // at least 10 seconds
+
+ int max_wait = max_wait_compiler_thread;
+
+ int attempts = 0;
+ JavaThreadIteratorWithHandle jtiwh;
+ while (true) {
+ int num_active = 0;
+ int num_active_compiler_thread = 0;
+
+ jtiwh.rewind();
+ for (; JavaThread *thr = jtiwh.next(); ) {
+ if (thr!=thr_cur && thr->thread_state() == _thread_in_native) {
+ num_active++;
+ if (thr->is_Compiler_thread()) {
+ num_active_compiler_thread++;
+ }
+ }
+ }
+
+ if (num_active == 0) {
+ return 0;
+ } else if (attempts > max_wait) {
+ return num_active;
+ } else if (num_active_compiler_thread == 0 && attempts > max_wait_user_thread) {
+ return num_active;
+ }
+
+ attempts++;
+
+ MutexLockerEx ml(&timer, Mutex::_no_safepoint_check_flag);
+ timer.wait(Mutex::_no_safepoint_check_flag, 10);
+ }
+}
+
+void VM_Exit::doit() {
+ CompileBroker::set_should_block();
+
+ // Wait for a short period for threads in native to block. Any thread
+ // still executing native code after the wait will be stopped at
+ // native==>Java/VM barriers.
+ // Among 16276 JCK tests, 94% of them come here without any threads still
+ // running in native; the other 6% are quiescent within 250ms (Ultra 80).
+ wait_for_threads_in_native_to_block();
+
+ set_vm_exited();
+
+ // cleanup globals resources before exiting. exit_globals() currently
+ // cleans up outputStream resources and PerfMemory resources.
+ exit_globals();
+
+ // Check for exit hook
+ exit_hook_t exit_hook = Arguments::exit_hook();
+ if (exit_hook != NULL) {
+ // exit hook should exit.
+ exit_hook(_exit_code);
+ // ... but if it didn't, we must do it here
+ vm_direct_exit(_exit_code);
+ } else {
+ vm_direct_exit(_exit_code);
+ }
+}
+
+
+void VM_Exit::wait_if_vm_exited() {
+ if (_vm_exited &&
+ Thread::current_or_null() != _shutdown_thread) {
+ // _vm_exited is set at safepoint, and the Threads_lock is never released
+ // we will block here until the process dies
+ Threads_lock->lock_without_safepoint_check();
+ ShouldNotReachHere();
+ }
+}
+
+void VM_PrintCompileQueue::doit() {
+ CompileBroker::print_compile_queues(_out);
+}
+
+#if INCLUDE_SERVICES
+void VM_PrintClassHierarchy::doit() {
+ KlassHierarchy::print_class_hierarchy(_out, _print_interfaces, _print_subclasses, _classname);
+}
+#endif