Merge pull request #169 from HFTrader/fix-spinlock-memory-order

Use memory_order_acquire for spinlock instead of acq_rel

Author: manugoyal

libcuckoo/cuckoohash_map.hh

@@ -834,14 +834,14 @@ private:
     }
 
     void lock() noexcept {
-      while (lock_.test_and_set(std::memory_order_acq_rel))
+      while (lock_.test_and_set(std::memory_order_acquire))
         ;
     }
 
     void unlock() noexcept { lock_.clear(std::memory_order_release); }
 
     bool try_lock() noexcept {
-      return !lock_.test_and_set(std::memory_order_acq_rel);
+      return !lock_.test_and_set(std::memory_order_acquire);
     }
 
     counter_type &elem_counter() noexcept { return elem_counter_; }