+#if defined(__linux__) && !FOLLY_MOBILE
constexpr auto kIsLinux = true;
#else
constexpr auto kIsLinux = false;
constexpr auto kIsLinux = true;
#else
constexpr auto kIsLinux = false;
#include <folly/portability/SysSyscall.h>
#include <folly/portability/Unistd.h>
#include <folly/portability/SysSyscall.h>
#include <folly/portability/Unistd.h>
-#if !defined(__NR_membarrier) && FOLLY_X64 && !FOLLY_MOBILE && \
- defined(__linux__)
+#if FOLLY_X64 && !FOLLY_MOBILE && defined(__linux__)
+#define FOLLY_USE_SYS_MEMBARRIER 1
+#if !defined(__NR_membarrier)
#define __NR_membarrier 324
#define MEMBARRIER_CMD_QUERY 0
#define MEMBARRIER_CMD_SHARED 1
#endif
#define __NR_membarrier 324
#define MEMBARRIER_CMD_QUERY 0
#define MEMBARRIER_CMD_SHARED 1
#endif
namespace folly {
namespace detail {
namespace folly {
namespace detail {
+#if FOLLY_USE_SYS_MEMBARRIER
auto r = syscall(__NR_membarrier, MEMBARRIER_CMD_QUERY, /* flags = */ 0);
if (r == -1) {
return false;
auto r = syscall(__NR_membarrier, MEMBARRIER_CMD_QUERY, /* flags = */ 0);
if (r == -1) {
return false;
+#if FOLLY_USE_SYS_MEMBARRIER
return syscall(__NR_membarrier, MEMBARRIER_CMD_SHARED, /* flags = */ 0);
#else
return -1;
return syscall(__NR_membarrier, MEMBARRIER_CMD_SHARED, /* flags = */ 0);
#else
return -1;