Adding addTaskFuture and addTaskRemoteFuture to FiberManager.

[folly.git] / folly / Singleton-inl.h

diff --git a/folly/Singleton-inl.h b/folly/Singleton-inl.h
index e946e8a51ba632b695f7c2af962100ad769a8770..e9a1963a480233f41b1422c6d0376b5924e73583 100644 (file)
--- a/folly/Singleton-inl.h
+++ b/folly/Singleton-inl.h
@@ -76,7 +76,8 @@ void SingletonHolder<T>::registerSingletonMock(CreateFunc c, TeardownFunc t) {
 
 template <typename T>
 T* SingletonHolder<T>::get() {
-  if (LIKELY(state_ == SingletonHolderState::Living)) {
+  if (LIKELY(state_.load(std::memory_order_acquire) ==
+             SingletonHolderState::Living)) {
     return instance_ptr_;
   }
   createInstance();
@@ -93,13 +94,34 @@ T* SingletonHolder<T>::get() {
 
 template <typename T>
 std::weak_ptr<T> SingletonHolder<T>::get_weak() {
-  if (UNLIKELY(state_ != SingletonHolderState::Living)) {
+  if (UNLIKELY(state_.load(std::memory_order_acquire) !=
+               SingletonHolderState::Living)) {
     createInstance();
   }
 
   return instance_weak_;
 }
 
+template <typename T>
+std::shared_ptr<T> SingletonHolder<T>::try_get() {
+  if (UNLIKELY(state_.load(std::memory_order_acquire) !=
+               SingletonHolderState::Living)) {
+    createInstance();
+  }
+
+  return instance_weak_.lock();
+}
+
+template <typename T>
+folly::ReadMostlySharedPtr<T> SingletonHolder<T>::try_get_fast() {
+  if (UNLIKELY(state_.load(std::memory_order_acquire) !=
+               SingletonHolderState::Living)) {
+    createInstance();
+  }
+
+  return instance_weak_fast_.lock();
+}
+
 template <typename T>
 TypeDescriptor SingletonHolder<T>::type() {
   return type_;
@@ -196,7 +218,7 @@ void SingletonHolder<T>::createInstance() {
   auto type_name = type_.name();
 
   // Can't use make_shared -- no support for a custom deleter, sadly.
-  instance_ = std::shared_ptr<T>(
+  std::shared_ptr<T> instance(
     create_(),
     [destroy_baton, print_destructor_stack_trace, teardown, type_name]
     (T* instance_ptr) mutable {
@@ -224,8 +246,11 @@ void SingletonHolder<T>::createInstance() {
   // constructor
   SingletonVault::scheduleDestroyInstances();
 
-  instance_weak_ = instance_;
-  instance_ptr_ = instance_.get();
+  instance_weak_ = instance;
+  instance_ptr_ = instance.get();
+  instance_.reset(std::move(instance));
+  instance_weak_fast_ = instance_;
+
   destroy_baton_ = std::move(destroy_baton);
   print_destructor_stack_trace_ = std::move(print_destructor_stack_trace);