void IdealGraphPrinter::clean_up() {
JavaThread *p;
for (p = Threads::first(); p; p = p->next()) {
if (p->is_Compiler_thread()) {
CompilerThread *c = (CompilerThread *)p;
IdealGraphPrinter *printer = c->ideal_graph_printer();
if (printer) {
delete printer;
}
c->set_ideal_graph_printer(NULL);
}
}
}
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;
while (true) {
int num_active = 0;
int num_active_compiler_thread = 0;
for(JavaThread *thr = Threads::first(); thr != NULL; thr = thr->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);
}
}
IdealGraphPrinter *IdealGraphPrinter::printer() {
if (PrintIdealGraphLevel == 0) return NULL;
JavaThread *thread = JavaThread::current();
if (!thread->is_Compiler_thread()) return NULL;
CompilerThread *compiler_thread = (CompilerThread *)thread;
if (compiler_thread->ideal_graph_printer() == NULL) {
IdealGraphPrinter *printer = new IdealGraphPrinter();
compiler_thread->set_ideal_graph_printer(printer);
}
return compiler_thread->ideal_graph_printer();
}
void FlatProfiler::record_thread_ticks() {
int maxthreads, suspendedthreadcount;
JavaThread** threadsList;
bool interval_expired = false;
if (ProfileIntervals &&
(FlatProfiler::received_ticks >= interval_ticks_previous + ProfileIntervalsTicks)) {
interval_expired = true;
interval_ticks_previous = FlatProfiler::received_ticks;
}
// Try not to wait for the Threads_lock
if (Threads_lock->try_lock()) {
{ // Threads_lock scope
maxthreads = Threads::number_of_threads();
threadsList = NEW_C_HEAP_ARRAY(JavaThread *, maxthreads, mtInternal);
suspendedthreadcount = 0;
for (JavaThread* tp = Threads::first(); tp != NULL; tp = tp->next()) {
if (tp->is_Compiler_thread()) {
// Only record ticks for active compiler threads
CompilerThread* cthread = (CompilerThread*)tp;
if (cthread->task() != NULL) {
// The compiler is active. If we need to access any of the fields
// of the compiler task we should suspend the CompilerThread first.
FlatProfiler::compiler_ticks += 1;
continue;
}
}
// First externally suspend all threads by marking each for
// external suspension - so it will stop at its next transition
// Then do a safepoint
ThreadProfiler* pp = tp->get_thread_profiler();
if (pp != NULL && pp->engaged) {
MutexLockerEx ml(tp->SR_lock(), Mutex::_no_safepoint_check_flag);
if (!tp->is_external_suspend() && !tp->is_exiting()) {
tp->set_external_suspend();
threadsList[suspendedthreadcount++] = tp;
}
}
}
Threads_lock->unlock();
}
JavaCallWrapper::JavaCallWrapper(methodHandle callee_method, Handle receiver, JavaValue* result, TRAPS) {
JavaThread* thread = (JavaThread *)THREAD;
bool clear_pending_exception = true;
guarantee(thread->is_Java_thread(), "crucial check - the VM thread cannot and must not escape to Java code");
assert(!thread->owns_locks(), "must release all locks when leaving VM");
guarantee(!thread->is_Compiler_thread(), "cannot make java calls from the compiler");
_result = result;
// Allocate handle block for Java code. This must be done before we change thread_state to _thread_in_Java_or_stub,
// since it can potentially block.
JNIHandleBlock* new_handles = JNIHandleBlock::allocate_block(thread);
// After this, we are official in JavaCode. This needs to be done before we change any of the thread local
// info, since we cannot find oops before the new information is set up completely.
ThreadStateTransition::transition(thread, _thread_in_vm, _thread_in_Java);
// Make sure that we handle asynchronous stops and suspends _before_ we clear all thread state
// in JavaCallWrapper::JavaCallWrapper(). This way, we can decide if we need to do any pd actions
// to prepare for stop/suspend (flush register windows on sparcs, cache sp, or other state).
if (thread->has_special_runtime_exit_condition()) {
thread->handle_special_runtime_exit_condition();
if (HAS_PENDING_EXCEPTION) {
clear_pending_exception = false;
}
}
// Make sure to set the oop's after the thread transition - since we can block there. No one is GC'ing
// the JavaCallWrapper before the entry frame is on the stack.
_callee_method = callee_method();
_receiver = receiver();
#ifdef CHECK_UNHANDLED_OOPS
THREAD->allow_unhandled_oop(&_receiver);
#endif // CHECK_UNHANDLED_OOPS
_thread = (JavaThread *)thread;
_handles = _thread->active_handles(); // save previous handle block & Java frame linkage
// For the profiler, the last_Java_frame information in thread must always be in
// legal state. We have no last Java frame if last_Java_sp == NULL so
// the valid transition is to clear _last_Java_sp and then reset the rest of
// the (platform specific) state.
_anchor.copy(_thread->frame_anchor());
_thread->frame_anchor()->clear();
debug_only(_thread->inc_java_call_counter());
_thread->set_active_handles(new_handles); // install new handle block and reset Java frame linkage
assert (_thread->thread_state() != _thread_in_native, "cannot set native pc to NULL");
// clear any pending exception in thread (native calls start with no exception pending)
if(clear_pending_exception) {
_thread->clear_pending_exception();
}
if (_anchor.last_Java_sp() == NULL) {
_thread->record_base_of_stack_pointer();
}
}