Move IsDaemon to native code.
Having the daemon status in the managed heap means it is only readable
by an attached thread in the runnable state. This is problematic when
terminating the VM.
Add extra asserts that ScopedJniThreadState and Thread::SetState only
occur on expected threads.
Remember a cause for no thread suspension asserting.
Change-Id: I8cf35c4c77751f8b1a35a5fb9a7f67682bf153bc
diff --git a/src/thread.cc b/src/thread.cc
index 8fe0160..104b9b9 100644
--- a/src/thread.cc
+++ b/src/thread.cc
@@ -207,8 +207,8 @@
delete[] allocated_signal_stack;
}
-void Thread::CreateNativeThread(JNIEnv* env, jobject java_peer, size_t stack_size) {
- Thread* native_thread = new Thread;
+void Thread::CreateNativeThread(JNIEnv* env, jobject java_peer, size_t stack_size, bool daemon) {
+ Thread* native_thread = new Thread(daemon);
{
ScopedJniThreadState ts(env);
Object* peer = ts.Decode<Object*>(java_peer);
@@ -277,7 +277,7 @@
}
Thread* Thread::Attach(const char* thread_name, bool as_daemon, jobject thread_group) {
- Thread* self = new Thread;
+ Thread* self = new Thread(as_daemon);
self->Init();
self->SetState(kNative);
@@ -599,12 +599,20 @@
}
void Thread::SetStateWithoutSuspendCheck(ThreadState new_state) {
+ DCHECK_EQ(this, Thread::Current());
volatile void* raw = reinterpret_cast<volatile void*>(&state_);
volatile int32_t* addr = reinterpret_cast<volatile int32_t*>(raw);
android_atomic_release_store(new_state, addr);
}
ThreadState Thread::SetState(ThreadState new_state) {
+ if (new_state != kVmWait && new_state != kTerminated) {
+ // TODO: kVmWait is set by the parent thread to a child thread to indicate it can go. Similarly
+ // kTerminated may be set by a parent thread to its child if pthread creation fails. This
+ // overloaded use of the state variable means we cannot fully assert that only threads
+ // themselves modify their state.
+ DCHECK_EQ(this, Thread::Current());
+ }
ThreadState old_state = state_;
if (old_state == kRunnable) {
// Non-runnable states are points where we expect thread suspension can occur.
@@ -764,7 +772,7 @@
CHECK_PTHREAD_CALL(pthread_key_delete, (Thread::pthread_key_self_), "self key");
}
-Thread::Thread()
+Thread::Thread(bool daemon)
: suspend_count_(0),
card_table_(NULL),
exception_(NULL),
@@ -793,7 +801,9 @@
debug_invoke_req_(new DebugInvokeReq),
trace_stack_(new std::vector<TraceStackFrame>),
name_(new std::string(kThreadNameDuringStartup)),
- no_thread_suspension_(0) {
+ daemon_(daemon),
+ no_thread_suspension_(0),
+ last_no_thread_suspension_cause_(NULL) {
CHECK_EQ((sizeof(Thread) % 4), 0U) << sizeof(Thread);
memset(&held_mutexes_[0], 0, sizeof(held_mutexes_));
}
@@ -1065,14 +1075,18 @@
// object graph.
method_trace->Set(depth, dex_pc_trace);
// Set the Object*s and assert that no thread suspension is now possible.
- ts.Self()->StartAssertNoThreadSuspension();
+ const char* last_no_suspend_cause =
+ ts.Self()->StartAssertNoThreadSuspension("Building internal stack trace");
+ CHECK(last_no_suspend_cause == NULL) << last_no_suspend_cause;
method_trace_ = method_trace.get();
dex_pc_trace_ = dex_pc_trace;
return true;
}
virtual ~BuildInternalStackTraceVisitor() {
- Thread::Current()->EndAssertNoThreadSuspension();
+ if (method_trace_ != NULL) {
+ Thread::Current()->EndAssertNoThreadSuspension(NULL);
+ }
}
bool VisitFrame() {
@@ -1436,7 +1450,12 @@
throw_frame_id_(0), throw_dex_pc_(0), handler_quick_frame_(NULL),
handler_quick_frame_pc_(0), handler_dex_pc_(0), native_method_count_(0),
method_tracing_active_(Runtime::Current()->IsMethodTracingActive()) {
- self->StartAssertNoThreadSuspension(); // Exception not in root sets, can't allow GC.
+ // Exception not in root sets, can't allow GC.
+ last_no_assert_suspension_cause_ = self->StartAssertNoThreadSuspension("Finding catch block");
+ }
+
+ ~CatchBlockStackVisitor() {
+ LOG(FATAL) << "UNREACHABLE"; // Expected to take long jump.
}
bool VisitFrame() {
@@ -1496,8 +1515,8 @@
LOG(INFO) << "Handler: " << PrettyMethod(catch_method) << " (line: " << line_number << ")";
}
}
- self_->SetException(exception_);
- self_->EndAssertNoThreadSuspension(); // Exception back in root set.
+ self_->SetException(exception_); // Exception back in root set.
+ self_->EndAssertNoThreadSuspension(last_no_assert_suspension_cause_);
// Place context back on thread so it will be available when we continue.
self_->ReleaseLongJumpContext(context_);
context_->SetSP(reinterpret_cast<uintptr_t>(handler_quick_frame_));
@@ -1525,6 +1544,8 @@
uint32_t native_method_count_;
// Is method tracing active?
const bool method_tracing_active_;
+ // Support for nesting no thread suspension checks.
+ const char* last_no_assert_suspension_cause_;
};
void Thread::DeliverException() {
@@ -1595,11 +1616,6 @@
return object->GetThinLockId() == thin_lock_id_;
}
-bool Thread::IsDaemon() {
- ScopedJniThreadState ts(this);
- return ts.DecodeField(WellKnownClasses::java_lang_Thread_daemon)->GetBoolean(peer_);
-}
-
class ReferenceMapVisitor : public StackVisitor {
public:
ReferenceMapVisitor(const ManagedStack* stack, const std::vector<TraceStackFrame>* trace_stack,