Completely remove InterruptableThreadState and Fix ThreadRegistry leak

runtime/vm/thread.cc

 // Copyright (c) 2015, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/thread.h"
 
 #include "vm/growable_array.h"
 #include "vm/isolate.h"
 #include "vm/lockers.h"
 #include "vm/object.h"
 #include "vm/os_thread.h"
 #include "vm/profiler.h"
 #include "vm/stub_code.h"
 #include "vm/thread_interrupter.h"
 #include "vm/thread_registry.h"
 
 namespace dart {
 
 // The single thread local key which stores all the thread local data
 // for a thread.
 ThreadLocalKey Thread::thread_key_ = OSThread::kUnsetThreadLocalKey;
 
 
+// Remove |thread| from each isolate's thread registry.
+class ThreadPruner : public IsolateVisitor {
+ public:
+  explicit ThreadPruner(Thread* thread)
+      : thread_(thread) {
+    ASSERT(thread_ != NULL);
+  }
+
+  void VisitIsolate(Isolate* isolate) {
+    ThreadRegistry* registry = isolate->thread_registry();
+    ASSERT(registry != NULL);
+    registry->PruneThread(thread_);
+  }
+ private:
+  Thread* thread_;
+};
+
+
 static void DeleteThread(void* thread) {
   delete reinterpret_cast<Thread*>(thread);
 }
 
 
 Thread::~Thread() {
   // We should cleanly exit any isolate before destruction.
   ASSERT(isolate_ == NULL);
+  // Clear |this| from all isolate's thread registry.
+  ThreadPruner pruner(this);
+  Isolate::VisitIsolates(&pruner);
 }
 
 
 void Thread::InitOnceBeforeIsolate() {
   ASSERT(thread_key_ == OSThread::kUnsetThreadLocalKey);
   thread_key_ = OSThread::CreateThreadLocal(DeleteThread);
   ASSERT(thread_key_ != OSThread::kUnsetThreadLocalKey);
   ASSERT(Thread::Current() == NULL);
-  // Postpone initialization of VM constants for this first thread.
-  SetCurrent(new Thread(false));
+  // Allocate a new Thread and postpone initialization of VM constants for
+  // this first thread.
+  Thread* thread = new Thread(false);
+  // Verify that current thread was set.
+  ASSERT(Thread::Current() == thread);
 }
 
 
 void Thread::InitOnceAfterObjectAndStubCode() {
   Thread* thread = Thread::Current();
   ASSERT(thread != NULL);
   ASSERT(thread->isolate() == Dart::vm_isolate());
   thread->InitVMConstants();
 }
 
 
 void Thread::SetCurrent(Thread* current) {
   OSThread::SetThreadLocal(thread_key_, reinterpret_cast<uword>(current));
 }
 
 
 void Thread::EnsureInit() {
   if (Thread::Current() == NULL) {
-    SetCurrent(new Thread());
+    // Allocate a new Thread.
+    Thread* thread = new Thread();
+    // Verify that current thread was set.
+    ASSERT(Thread::Current() == thread);
   }
 }
 
 
 #if defined(TARGET_OS_WINDOWS)
 void Thread::CleanUp() {
   Thread* current = Current();
   if (current != NULL) {
     delete current;
   }
   SetCurrent(NULL);
 }
 #endif
 
 
 Thread::Thread(bool init_vm_constants)
-    : isolate_(NULL),
+    : id_(OSThread::GetCurrentThreadId()),
+      isolate_(NULL),
       store_buffer_block_(NULL) {
   ClearState();
 #define DEFAULT_INIT(type_name, member_name, init_expr, default_init_value)    \
   member_name = default_init_value;
 CACHED_CONSTANTS_LIST(DEFAULT_INIT)
 #undef DEFAULT_INIT
   if (init_vm_constants) {
     InitVMConstants();
   }
+  SetCurrent(this);
 }
 
 
 void Thread::InitVMConstants() {
 #define ASSERT_VM_HEAP(type_name, member_name, init_expr, default_init_value)  \
   ASSERT((init_expr)->IsOldObject());
 CACHED_VM_OBJECTS_LIST(ASSERT_VM_HEAP)
 #undef ASSERT_VM_HEAP
 
 #define INIT_VALUE(type_name, member_name, init_expr, default_init_value)      \
@@ skipping 27 matching lines @@
   ASSERT(thread->isolate() == NULL);
   ASSERT(!isolate->HasMutatorThread());
   thread->isolate_ = isolate;
   isolate->MakeCurrentThreadMutator(thread);
   isolate->set_vm_tag(VMTag::kVMTagId);
   ASSERT(thread->store_buffer_block_ == NULL);
   thread->StoreBufferAcquire();
   ASSERT(isolate->heap() != NULL);
   thread->heap_ = isolate->heap();
   thread->Schedule(isolate);
-  ASSERT(thread->thread_state() == NULL);
-  InterruptableThreadState* thread_state =
-      ThreadInterrupter::GetCurrentThreadState();
-#if defined(DEBUG)
-  thread->set_thread_state(NULL);  // Exclude thread itself from the dupe check.
-  Isolate::CheckForDuplicateThreadState(thread_state);
-  thread->set_thread_state(thread_state);
-#endif
-  ASSERT(thread_state != NULL);
   // TODO(koda): Migrate profiler interface to use Thread.
   Profiler::BeginExecution(isolate);
 }
 
 
 void Thread::ExitIsolate() {
   Thread* thread = Thread::Current();
   // TODO(koda): Audit callers; they should know whether they're in an isolate.
   if (thread == NULL || thread->isolate() == NULL) return;
   Isolate* isolate = thread->isolate();
   Profiler::EndExecution(isolate);
-  thread->set_thread_state(NULL);
   thread->Unschedule();
   // TODO(koda): Move store_buffer_block_ into State.
   thread->StoreBufferRelease();
   if (isolate->is_runnable()) {
     isolate->set_vm_tag(VMTag::kIdleTagId);
   } else {
     isolate->set_vm_tag(VMTag::kLoadWaitTagId);
   }
   isolate->ClearMutatorThread();
   thread->isolate_ = NULL;
@@ skipping 87 matching lines @@
   return isolate_->cha_;
 }
 
 
 void Thread::set_cha(CHA* value) {
   ASSERT(isolate_ != NULL);
   isolate_->cha_ = value;
 }
 
 
+void Thread::SetThreadInterrupter(ThreadInterruptCallback callback,
+                                  void* data) {
+  ASSERT(Thread::Current() == this);
+  thread_interrupt_callback_ = callback;
+  thread_interrupt_data_ = data;
+}
+
+
+bool Thread::IsThreadInterrupterEnabled(ThreadInterruptCallback* callback,
+                                        void** data) const {
+#if defined(TARGET_OS_WINDOWS)
+  // On Windows we expect this to be called from the thread interrupter thread.
+  ASSERT(id() != OSThread::GetCurrentThreadId());
+#else
+  // On posix platforms, we expect this to be called from signal handler.
+  ASSERT(id() == OSThread::GetCurrentThreadId());
+#endif
+  ASSERT(callback != NULL);
+  ASSERT(data != NULL);
+  *callback = thread_interrupt_callback_;
+  *data = thread_interrupt_data_;
+  return (*callback != NULL) &&
+         (*data != NULL);
+}
+
+
 bool Thread::CanLoadFromThread(const Object& object) {
 #define CHECK_OBJECT(type_name, member_name, expr, default_init_value)         \
   if (object.raw() == expr) return true;
 CACHED_VM_OBJECTS_LIST(CHECK_OBJECT)
 #undef CHECK_OBJECT
   return false;
 }
 
 
 intptr_t Thread::OffsetFromThread(const Object& object) {
 #define COMPUTE_OFFSET(type_name, member_name, expr, default_init_value)       \
   ASSERT((expr)->IsVMHeapObject());                                            \
   if (object.raw() == expr) return Thread::member_name##offset();
 CACHED_VM_OBJECTS_LIST(COMPUTE_OFFSET)
 #undef COMPUTE_OFFSET
   UNREACHABLE();
   return -1;
 }
 
 }  // namespace dart