Make thread local variables fiber friendly

2 files changed, 40 insertions, 0 deletions

diff --git a/library/cpp/yt/misc/tls-inl.h b/library/cpp/yt/misc/tls-inl.h
new file mode 100644
index 0000000000..51ef91517f
--- /dev/null
+++ b/library/cpp/yt/misc/tls-inl.h
@@ -0,0 +1,18 @@
+#ifndef TLS_INL_H_
+#error "Direct inclusion of this file is not allowed, include tls.h"
+// For the sake of sane code completion.
+#include "tls.h"
+#endif
+
+namespace NYT {
+
+////////////////////////////////////////////////////////////////////////////////
+
+template <class T>
+T& GetTlsRef(volatile T& arg)
+{
+    return const_cast<T&>(arg);
+}
+////////////////////////////////////////////////////////////////////////////////
+
+} // namespace NYT
diff --git a/library/cpp/yt/misc/tls.h b/library/cpp/yt/misc/tls.h
new file mode 100644
index 0000000000..d1bda8ac68
--- /dev/null
+++ b/library/cpp/yt/misc/tls.h
@@ -0,0 +1,22 @@
+#pragma once
+
+#include <util/system/compiler.h>
+
+// Workaround for fiber (un)friendly TLS.
+// Volatile qualifier prevents caching access to thread local variables.
+#define YT_THREAD_LOCAL(...) thread_local __VA_ARGS__ volatile
+
+namespace NYT {
+
+////////////////////////////////////////////////////////////////////////////////
+
+template <class T>
+Y_FORCE_INLINE T& GetTlsRef(volatile T& arg);
+
+////////////////////////////////////////////////////////////////////////////////
+
+} // namespace NYT
+
+#define TLS_INL_H_
+#include "tls-inl.h"
+#undef TLS_INL_H_