Added fence to counters to prevent data race

solarwinds · Oct 15, 2024 · 2ac2892 · 2ac2892
1 parent dcf5718
commit 2ac2892
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Showing 2 changed files with 5 additions and 1 deletion.
diff --git a/util/counter_to_rate.h b/util/counter_to_rate.h
@@ -6,6 +6,7 @@
 #pragma once
 
 #include <utility>
+#include <atomic>
 
 #include <cstdlib>
 
@@ -18,7 +19,7 @@ template <typename T> struct CounterToRate {
 
   constexpr CounterToRate(T data, T prev = {}) : value_{std::move(data)}, prev_{std::move(prev)}, count_{1} {}
 
-  constexpr T peek_rate() const { return value_ - prev_; }
+  constexpr T peek_rate() const { std::atomic_thread_fence(std::memory_order_acquire); return value_ - prev_; }
   constexpr T commit_rate(bool empty_if_unitary = false);
 
   constexpr T const &value() const { return value_; }

diff --git a/util/counter_to_rate.inl b/util/counter_to_rate.inl
@@ -12,7 +12,10 @@ namespace data {
 template <typename T> constexpr T CounterToRate<T>::commit_rate(bool empty_if_unitary)
 {
   T choice[2] = {value_ - prev_, T{}};
+  std::atomic_thread_fence(std::memory_order_release); 
   prev_ = value_;
+
+  std::atomic_thread_fence(std::memory_order_acquire);
   return choice[empty_if_unitary & (count_ < 2)];
 }