cache_line_size.h

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//
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#ifndef MYSQL_CONCURRENCY_CACHE_LINE_SIZE
#define MYSQL_CONCURRENCY_CACHE_LINE_SIZE
 
#include <new>  // std::hardware_destructive_interference_size
 
#include "my_compiler.h"  // MY_COMPILER_DIAGNOSTIC_*
 
namespace mysql::concurrency::detail {
 
MY_COMPILER_DIAGNOSTIC_PUSH()
#if defined(__GNUC__) && !defined(__clang__) && (__GNUC__ >= 12)
MY_COMPILER_GCC_DIAGNOSTIC_IGNORE("-Winterference-size")
#endif
#ifdef __cpp_lib_hardware_interference_size
constexpr inline std::size_t hardware_destructive_interference_size =
    std::hardware_destructive_interference_size;
#else
// Fallback for pre-C++17 libs; typical x86/ARM cache line size
constexpr inline std::size_t hardware_destructive_interference_size = 64;
#endif
MY_COMPILER_DIAGNOSTIC_POP()
 
}  // namespace mysql::concurrency::detail
 
#endif  // MYSQL_CONCURRENCY_CACHE_LINE_SIZE