Use membarrier in TLRefCount

[folly.git] / folly / experimental / AsymmetricMemoryBarrier.h

diff --git a/folly/experimental/AsymmetricMemoryBarrier.h b/folly/experimental/AsymmetricMemoryBarrier.h
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+++ b/folly/experimental/AsymmetricMemoryBarrier.h
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+/*
+ * Copyright 2016 Facebook, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#pragma once
+
+#include <atomic>
+
+#include <folly/portability/Asm.h>
+
+namespace folly {
+
+FOLLY_ALWAYS_INLINE void asymmetricLightBarrier() {
+  if (kIsLinux) {
+    asm_volatile_memory();
+  } else {
+    std::atomic_thread_fence(std::memory_order_seq_cst);
+  }
+}
+
+void asymmetricHeavyBarrier();
+}