fix some bugs in AsyncSSLSocketTest
[folly.git] / folly / ProducerConsumerQueue.h
index 13948be45218e374777a012ad392d8c59c44cb76..57d41cca84b9599604bbca4581b3cf862b423fe2 100644 (file)
@@ -1,5 +1,5 @@
 /*
- * Copyright 2017 Facebook, Inc.
+ * Copyright 2012-present Facebook, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -167,15 +167,22 @@ struct ProducerConsumerQueue {
     return ret;
   }
 
-private:
- char pad0_[CacheLocality::kFalseSharingRange];
- const uint32_t size_;
- T* const records_;
+  // maximum number of items in the queue.
+  size_t capacity() const {
+    return size_ - 1;
+  }
+
+ private:
+  char pad0_[hardware_destructive_interference_size];
+  const uint32_t size_;
+  T* const records_;
 
- FOLLY_ALIGN_TO_AVOID_FALSE_SHARING std::atomic<unsigned int> readIndex_;
- FOLLY_ALIGN_TO_AVOID_FALSE_SHARING std::atomic<unsigned int> writeIndex_;
+  alignas(hardware_destructive_interference_size)
+      std::atomic<unsigned int> readIndex_;
+  alignas(hardware_destructive_interference_size)
+      std::atomic<unsigned int> writeIndex_;
 
char pad1_[CacheLocality::kFalseSharingRange - sizeof(writeIndex_)];
 char pad1_[hardware_destructive_interference_size - sizeof(writeIndex_)];
 };
 
-}
+} // namespace folly