X-Git-Url: https://git.liburcu.org/?a=blobdiff_plain;f=urcu%2Fmap%2Furcu.h;h=3f436a7375120366bca0898aafd3debdc45a48a5;hb=4157e1ac43033c8b3ef5405b9c01e8311b2454ca;hp=5942fad207102784e0c0f7f14f53734807c1de88;hpb=052fdaeea35b4742e398fbadcf3a2ce96e4b868a;p=urcu.git

diff --git a/urcu/map/urcu.h b/urcu/map/urcu.h
index 5942fad..3f436a7 100644
--- a/urcu/map/urcu.h
+++ b/urcu/map/urcu.h
@@ -38,6 +38,31 @@
 #define RCU_MEMBARRIER
 #endif
 
+/*
+ * RCU_MEMBARRIER is only possibly available on Linux. Fallback to
+ * RCU_MB
+ * otherwise.
+ */
+#if !defined(__linux__) && defined(RCU_MEMBARRIER)
+#undef RCU_MEMBARRIER
+#define RCU_MB
+#endif
+
+#ifdef RCU_MEMBARRIER
+#include <syscall.h>
+
+/* If the headers do not support SYS_membarrier, statically use RCU_MB */
+#ifdef SYS_membarrier
+# define MEMBARRIER_EXPEDITED		(1 << 0)
+# define MEMBARRIER_DELAYED		(1 << 1)
+# define MEMBARRIER_QUERY		(1 << 16)
+# define membarrier(...)		syscall(SYS_membarrier, __VA_ARGS__)
+#else
+# undef RCU_MEMBARRIER
+# define RCU_MB
+#endif
+#endif
+
 #ifdef RCU_MEMBARRIER
 
 #define rcu_read_lock			rcu_read_lock_memb