folly: fix clang's -Wundefined-var-template

[folly.git] / folly / detail / CacheLocality.h

diff --git a/folly/detail/CacheLocality.h b/folly/detail/CacheLocality.h
index 1ede43cbef70b4f60d4f06f40a77890be419dfa1..c9baf5281ac35afb97fd1aea184162a0ede740d0 100644 (file)
--- a/folly/detail/CacheLocality.h
+++ b/folly/detail/CacheLocality.h
@@ -161,6 +161,16 @@ struct SequentialThreadId {
 
   static FOLLY_TLS size_t currentId;
 };
+
+template <template <typename> class Atom>
+Atom<size_t> SequentialThreadId<Atom>::prevId(0);
+
+template <template <typename> class Atom>
+FOLLY_TLS size_t SequentialThreadId<Atom>::currentId(0);
+
+// Suppress this instantiation in other translation units. It is
+// instantiated in CacheLocality.cpp
+extern template struct SequentialThreadId<std::atomic>;
 #endif
 
 struct HashingThreadId {
@@ -277,7 +287,10 @@ struct AccessSpreader {
   static bool initialized;
 
   /// Returns the best getcpu implementation for Atom
-  static Getcpu::Func pickGetcpuFunc();
+  static Getcpu::Func pickGetcpuFunc() {
+    auto best = Getcpu::resolveVdsoFunc();
+    return best ? best : &FallbackGetcpuType::getcpu;
+  }
 
   /// Always claims to be on CPU zero, node zero
   static int degenerateGetcpu(unsigned* cpu, unsigned* node, void*) {
@@ -326,22 +339,20 @@ struct AccessSpreader {
   }
 };
 
-template <>
-Getcpu::Func AccessSpreader<std::atomic>::pickGetcpuFunc();
-
-#define DECLARE_ACCESS_SPREADER_TYPE(Atom)                                     \
-  namespace folly {                                                            \
-  namespace detail {                                                           \
-  template <>                                                                  \
-  Getcpu::Func AccessSpreader<Atom>::getcpuFunc =                              \
-      AccessSpreader<Atom>::degenerateGetcpu;                                  \
-  template <>                                                                  \
-  typename AccessSpreader<Atom>::CompactStripe                                 \
-      AccessSpreader<Atom>::widthAndCpuToStripe[129][128] = {};                \
-  template <>                                                                  \
-  bool AccessSpreader<Atom>::initialized = AccessSpreader<Atom>::initialize(); \
-  }                                                                            \
-  }
+template <template <typename> class Atom>
+Getcpu::Func AccessSpreader<Atom>::getcpuFunc =
+    AccessSpreader<Atom>::degenerateGetcpu;
+
+template <template <typename> class Atom>
+typename AccessSpreader<Atom>::CompactStripe
+    AccessSpreader<Atom>::widthAndCpuToStripe[kMaxCpus + 1][kMaxCpus] = {};
+
+template <template <typename> class Atom>
+bool AccessSpreader<Atom>::initialized = AccessSpreader<Atom>::initialize();
+
+// Suppress this instantiation in other translation units. It is
+// instantiated in CacheLocality.cpp
+extern template struct AccessSpreader<std::atomic>;
 
 } // namespace detail
 } // namespace folly