- Add an OSThread structure which is the generic TLS structure for all C++

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/log.h"
 #include "vm/native_entry.h"
 #include "vm/object.h"
 #include "vm/os_thread.h"
 #include "vm/profiler.h"
 #include "vm/runtime_entry.h"
 #include "vm/stub_code.h"
 #include "vm/symbols.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;
-Thread* Thread::thread_list_head_ = NULL;
-Mutex* Thread::thread_list_lock_ = NULL;
-
-// 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_;
-};
-
-
-void Thread::AddThreadToList(Thread* thread) {
-  ASSERT(thread != NULL);
-  ASSERT(thread->isolate() == NULL);
-  ASSERT(thread_list_lock_ != NULL);
-  MutexLocker ml(thread_list_lock_);
-
-  ASSERT(thread->thread_list_next_ == NULL);
-
-#if defined(DEBUG)
-  {
-    // Ensure that we aren't already in the list.
-    Thread* current = thread_list_head_;
-    while (current != NULL) {
-      ASSERT(current != thread);
-      current = current->thread_list_next_;
-    }
-  }
-#endif
-
-  // Insert at head of list.
-  thread->thread_list_next_ = thread_list_head_;
-  thread_list_head_ = thread;
-}
-
-
-void Thread::RemoveThreadFromList(Thread* thread) {
-  ASSERT(thread != NULL);
-  ASSERT(thread->isolate() == NULL);
-  ASSERT(thread_list_lock_ != NULL);
-  MutexLocker ml(thread_list_lock_);
-
-  // Handle case where |thread| is head of list.
-  if (thread_list_head_ == thread) {
-    thread_list_head_ = thread->thread_list_next_;
-    thread->thread_list_next_ = NULL;
-    return;
-  }
-
-  Thread* current = thread_list_head_;
-  Thread* previous = NULL;
-
-  // Scan across list and remove |thread|.
-  while (current != NULL) {
-    previous = current;
-    current = current->thread_list_next_;
-    if (current == thread) {
-      // We found |thread|, remove from list.
-      previous->thread_list_next_ = current->thread_list_next_;
-      thread->thread_list_next_ = NULL;
-      return;
-    }
-  }
-
-  UNREACHABLE();
-}
-
-
-bool Thread::IsThreadInList(ThreadId join_id) {
-  if (join_id == OSThread::kInvalidThreadJoinId) {
-    return false;
-  }
-  ThreadIterator it;
-  while (it.HasNext()) {
-    Thread* t = it.Next();
-    // An address test is not sufficient because the allocator may recycle
-    // the address for another Thread. Test against the thread's join id.
-    if (t->join_id() == join_id) {
-      return true;
-    }
-  }
-  return false;
-}
-
-
-static void DeleteThread(void* thread) {
-  delete reinterpret_cast<Thread*>(thread);
-}
-
-
-void Thread::Shutdown() {
-  if (thread_list_lock_ != NULL) {
-    // Delete the current thread.
-    Thread* thread = Current();
-    ASSERT(thread != NULL);
-    delete thread;
-    thread = NULL;
-    SetCurrent(NULL);
-
-    // Check that there are no more threads, then delete the lock.
-    {
-      MutexLocker ml(thread_list_lock_);
-      ASSERT(thread_list_head_ == NULL);
-    }
-
-    // Clean up TLS.
-    OSThread::DeleteThreadLocal(thread_key_);
-    thread_key_ = OSThread::kUnsetThreadLocalKey;
-
-    // Delete the thread list lock.
-    delete thread_list_lock_;
-    thread_list_lock_ = NULL;
-  }
-}
-
-
 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);
-  delete log_;
-  log_ = NULL;
-  RemoveThreadFromList(this);
 }
 
 
-void Thread::InitOnceBeforeIsolate() {
-  ASSERT(thread_list_lock_ == NULL);
-  thread_list_lock_ = new Mutex();
-  ASSERT(thread_list_lock_ != NULL);
-  ASSERT(thread_key_ == OSThread::kUnsetThreadLocalKey);
-  thread_key_ = OSThread::CreateThreadLocal(DeleteThread);
-  ASSERT(thread_key_ != OSThread::kUnsetThreadLocalKey);
-  ASSERT(Thread::Current() == NULL);
-  // 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) {
-    // Allocate a new Thread.
-    Thread* thread = new Thread();
-    // Verify that current thread was set.
-    ASSERT(Thread::Current() == thread);
-  }
-}
-
-
 #if defined(DEBUG)
 #define REUSABLE_HANDLE_SCOPE_INIT(object)                                     \
   reusable_##object##_handle_scope_active_(false),
 #else
 #define REUSABLE_HANDLE_SCOPE_INIT(object)
 #endif  // defined(DEBUG)
 
 #define REUSABLE_HANDLE_INITIALIZERS(object)                                   \
   object##_handle_(NULL),
 
 
-Thread::Thread(bool init_vm_constants)
-    : id_(OSThread::GetCurrentThreadId()),
-      join_id_(OSThread::GetCurrentThreadJoinId()),
-      trace_id_(OSThread::GetCurrentThreadTraceId()),
-      thread_interrupt_disabled_(1),  // Thread interrupts disabled by default.
+Thread::Thread(Isolate* isolate)
+    : BaseThread(false),
+      os_thread_(NULL),
       isolate_(NULL),
       heap_(NULL),
-      timeline_block_(NULL),
+      zone_(NULL),
+      top_exit_frame_info_(0),
+      top_resource_(NULL),
+      long_jump_base_(NULL),
       store_buffer_block_(NULL),
-      log_(new class Log()),
-      REUSABLE_HANDLE_LIST(REUSABLE_HANDLE_INITIALIZERS)
-      REUSABLE_HANDLE_LIST(REUSABLE_HANDLE_SCOPE_INIT)
+      no_callback_scope_depth_(0),
+#if defined(DEBUG)
+      top_handle_scope_(NULL),
+      no_handle_scope_depth_(0),
+      no_safepoint_scope_depth_(0),
+#endif
       reusable_handles_(),
       cha_(NULL),
       deopt_id_(0),
       vm_tag_(0),
       pending_functions_(GrowableObjectArray::null()),
-      no_callback_scope_depth_(0),
-      thread_list_next_(NULL),
-      name_(NULL) {
-  ClearState();
-
+      REUSABLE_HANDLE_LIST(REUSABLE_HANDLE_INITIALIZERS)
+      REUSABLE_HANDLE_LIST(REUSABLE_HANDLE_SCOPE_INIT)
+      next_(NULL) {
 #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
 
 #define DEFAULT_INIT(name)                                                     \
   name##_entry_point_ = 0;
 RUNTIME_ENTRY_LIST(DEFAULT_INIT)
 #undef DEFAULT_INIT
 
 #define DEFAULT_INIT(returntype, name, ...)                                    \
   name##_entry_point_ = 0;
 LEAF_RUNTIME_ENTRY_LIST(DEFAULT_INIT)
 #undef DEFAULT_INIT
 
-  if (init_vm_constants) {
+  // We cannot initialize the VM constants here for the vm isolate thread
+  // due to boot strapping issues.
+  if ((Dart::vm_isolate() != NULL) && (isolate != Dart::vm_isolate())) {
     InitVMConstants();
   }
-  SetCurrent(this);
-  AddThreadToList(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 15 matching lines @@
 #undef INIT_VALUE
 
   // Setup the thread specific reusable handles.
 #define REUSABLE_HANDLE_ALLOCATION(object)                                     \
   this->object##_handle_ = this->AllocateReusableHandle<object>();
   REUSABLE_HANDLE_LIST(REUSABLE_HANDLE_ALLOCATION)
 #undef REUSABLE_HANDLE_ALLOCATION
 }
 
 
-void Thread::ClearState() {
-  memset(&state_, 0, sizeof(state_));
-  pending_functions_ = GrowableObjectArray::null();
-}
-
-
 RawGrowableObjectArray* Thread::pending_functions() {
   if (pending_functions_ == GrowableObjectArray::null()) {
     pending_functions_ = GrowableObjectArray::New(Heap::kOld);
   }
   return pending_functions_;
 }
 
 
-void Thread::Schedule(Isolate* isolate, bool bypass_safepoint) {
-  State st;
-  if (isolate->thread_registry()->RestoreStateTo(this, &st, bypass_safepoint)) {
-    ASSERT(isolate->thread_registry()->Contains(this));
-    state_ = st;
-  }
-}
-
-
-void Thread::Unschedule(bool bypass_safepoint) {
-  ThreadRegistry* reg = isolate_->thread_registry();
-  ASSERT(reg->Contains(this));
-  reg->SaveStateFrom(this, state_, bypass_safepoint);
-  ClearState();
-}
-
-
 void Thread::EnterIsolate(Isolate* isolate) {
-  Thread* thread = Thread::Current();
-  ASSERT(thread != NULL);
-  ASSERT(thread->isolate() == NULL);
-  ASSERT(!isolate->HasMutatorThread());
-  thread->isolate_ = isolate;
+  const bool kIsMutatorThread = true;
+  const bool kDontBypassSafepoints = false;
+  ThreadRegistry* tr = isolate->thread_registry();
+  Thread* thread = tr->Schedule(
+      isolate, kIsMutatorThread, kDontBypassSafepoints);
   isolate->MakeCurrentThreadMutator(thread);
   thread->set_vm_tag(VMTag::kVMTagId);
   ASSERT(thread->store_buffer_block_ == NULL);
   thread->StoreBufferAcquire();
-  ASSERT(isolate->heap() != NULL);
-  thread->heap_ = isolate->heap();
-  thread->Schedule(isolate);
-  thread->EnableThreadInterrupts();
 }
 
 
 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;
+  ASSERT(thread != NULL);
+  ASSERT(thread->IsMutatorThread());
 #if defined(DEBUG)
   ASSERT(!thread->IsAnyReusableHandleScopeActive());
 #endif  // DEBUG
-  thread->DisableThreadInterrupts();
   // Clear since GC will not visit the thread once it is unscheduled.
   thread->ClearReusableHandles();
+  thread->StoreBufferRelease();
   Isolate* isolate = thread->isolate();
-  thread->Unschedule();
-  // TODO(koda): Move store_buffer_block_ into State.
-  thread->StoreBufferRelease();
+  ASSERT(isolate != NULL);
   if (isolate->is_runnable()) {
     thread->set_vm_tag(VMTag::kIdleTagId);
   } else {
     thread->set_vm_tag(VMTag::kLoadWaitTagId);
   }
+  const bool kIsMutatorThread = true;
+  const bool kDontBypassSafepoints = false;
+  ThreadRegistry* tr = isolate->thread_registry();
+  tr->Unschedule(thread, kIsMutatorThread, kDontBypassSafepoints);
   isolate->ClearMutatorThread();
-  thread->isolate_ = NULL;
-  ASSERT(Isolate::Current() == NULL);
-  thread->heap_ = NULL;
 }
 
 
 void Thread::EnterIsolateAsHelper(Isolate* isolate, bool bypass_safepoint) {
-  Thread* thread = Thread::Current();
-  ASSERT(thread != NULL);
-  ASSERT(thread->isolate() == NULL);
-  thread->isolate_ = isolate;
+  const bool kIsNotMutatorThread = false;
+  ThreadRegistry* tr = isolate->thread_registry();
+  Thread* thread = tr->Schedule(isolate, kIsNotMutatorThread, bypass_safepoint);
   ASSERT(thread->store_buffer_block_ == NULL);
   // TODO(koda): Use StoreBufferAcquire once we properly flush before Scavenge.
   thread->store_buffer_block_ =
       thread->isolate()->store_buffer()->PopEmptyBlock();
-  ASSERT(isolate->heap() != NULL);
-  thread->heap_ = isolate->heap();
-  // Do not update isolate->mutator_thread, but perform sanity check:
-  // this thread should not be both the main mutator and helper.
+  // This thread should not be the main mutator.
   ASSERT(!thread->IsMutatorThread());
-  thread->Schedule(isolate, bypass_safepoint);
-  thread->EnableThreadInterrupts();
 }
 
 
 void Thread::ExitIsolateAsHelper(bool bypass_safepoint) {
   Thread* thread = Thread::Current();
-  thread->DisableThreadInterrupts();
+  ASSERT(thread != NULL);
+  ASSERT(!thread->IsMutatorThread());
+  thread->StoreBufferRelease();
   Isolate* isolate = thread->isolate();
   ASSERT(isolate != NULL);
-  thread->Unschedule(bypass_safepoint);
-  // TODO(koda): Move store_buffer_block_ into State.
-  thread->StoreBufferRelease();
-  thread->isolate_ = NULL;
-  thread->heap_ = NULL;
-  ASSERT(!thread->IsMutatorThread());
+  const bool kIsNotMutatorThread = false;
+  ThreadRegistry* tr = isolate->thread_registry();
+  tr->Unschedule(thread, kIsNotMutatorThread, bypass_safepoint);
 }
 
 
 // TODO(koda): Make non-static and invoke in SafepointThreads.
 void Thread::PrepareForGC() {
   Thread* thread = Thread::Current();
   // Prevent scheduling another GC.
   thread->StoreBufferRelease(StoreBuffer::kIgnoreThreshold);
   // Make sure to get an *empty* block; the isolate needs all entries
   // at GC time.
@@ skipping 47 matching lines @@
          (vm_tag() == VMTag::kDartTagId);
 }
 
 
 bool Thread::HasExitedDartCode() const {
   return (top_exit_frame_info() != 0) &&
          (vm_tag() != VMTag::kDartTagId);
 }
 
 
-CHA* Thread::cha() const {
-  ASSERT(isolate_ != NULL);
-  return cha_;
-}
-
-
-void Thread::set_cha(CHA* value) {
-  ASSERT(isolate_ != NULL);
-  cha_ = value;
-}
-
-
-Log* Thread::log() const {
-  return log_;
-}
-
-
 template<class C>
 C* Thread::AllocateReusableHandle() {
   C* handle = reinterpret_cast<C*>(reusable_handles_.AllocateScopedHandle());
   C::initializeHandle(handle, C::null());
   return handle;
 }
 
 
 void Thread::ClearReusableHandles() {
 #define CLEAR_REUSABLE_HANDLE(object)                                          \
   *object##_handle_ = object::null();
   REUSABLE_HANDLE_LIST(CLEAR_REUSABLE_HANDLE)
 #undef CLEAR_REUSABLE_HANDLE
 }
 
 
 void Thread::VisitObjectPointers(ObjectPointerVisitor* visitor) {
   ASSERT(visitor != NULL);
 
   // Visit objects in thread specific handles area.
   reusable_handles_.VisitObjectPointers(visitor);
 
   if (pending_functions_ != GrowableObjectArray::null()) {
     visitor->VisitPointer(
         reinterpret_cast<RawObject**>(&pending_functions_));
   }
 }
 
 
-void Thread::DisableThreadInterrupts() {
-  ASSERT(Thread::Current() == this);
-  AtomicOperations::FetchAndIncrement(&thread_interrupt_disabled_);
-}
-
-
-void Thread::EnableThreadInterrupts() {
-  ASSERT(Thread::Current() == this);
-  uintptr_t old =
-      AtomicOperations::FetchAndDecrement(&thread_interrupt_disabled_);
-  if (old == 1) {
-    // We just decremented from 1 to 0.
-    // Make sure the thread interrupter is awake.
-    ThreadInterrupter::WakeUp();
-  }
-  if (old == 0) {
-    // We just decremented from 0, this means we've got a mismatched pair
-    // of calls to EnableThreadInterrupts and DisableThreadInterrupts.
-    FATAL("Invalid call to Thread::EnableThreadInterrupts()");
-  }
-}
-
-
-bool Thread::ThreadInterruptsEnabled() {
-  return AtomicOperations::LoadRelaxed(&thread_interrupt_disabled_) == 0;
-}
-
-
 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) {
@@ skipping 32 matching lines @@
     return Thread::name##_entry_point_offset();                                \
   }
 LEAF_RUNTIME_ENTRY_LIST(COMPUTE_OFFSET)
 #undef COMPUTE_OFFSET
 
   UNREACHABLE();
   return -1;
 }
 
 
-ThreadIterator::ThreadIterator() {
-  ASSERT(Thread::thread_list_lock_ != NULL);
-  // Lock the thread list while iterating.
-  Thread::thread_list_lock_->Lock();
-  next_ = Thread::thread_list_head_;
-}
-
-
-ThreadIterator::~ThreadIterator() {
-  ASSERT(Thread::thread_list_lock_ != NULL);
-  // Unlock the thread list when done.
-  Thread::thread_list_lock_->Unlock();
-}
-
-
-bool ThreadIterator::HasNext() const {
-  ASSERT(Thread::thread_list_lock_ != NULL);
-  ASSERT(Thread::thread_list_lock_->IsOwnedByCurrentThread());
-  return next_ != NULL;
-}
-
-
-Thread* ThreadIterator::Next() {
-  ASSERT(Thread::thread_list_lock_ != NULL);
-  ASSERT(Thread::thread_list_lock_->IsOwnedByCurrentThread());
-  Thread* current = next_;
-  next_ = next_->thread_list_next_;
-  return current;
-}
-
-
 DisableThreadInterruptsScope::DisableThreadInterruptsScope(Thread* thread)
     : StackResource(thread) {
   if (thread != NULL) {
-    thread->DisableThreadInterrupts();
+    OSThread* os_thread = thread->os_thread();
+    ASSERT(os_thread != NULL);
+    os_thread->DisableThreadInterrupts();
   }
 }
 
 
 DisableThreadInterruptsScope::~DisableThreadInterruptsScope() {
   if (thread() != NULL) {
-    thread()->EnableThreadInterrupts();
+    OSThread* os_thread = thread()->os_thread();
+    ASSERT(os_thread != NULL);
+    os_thread->EnableThreadInterrupts();
   }
 }
 
 }  // namespace dart