um: take userland definition of barrier() to user.h
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Richard Weinberger <richard@nod.at>
diff --git a/arch/um/include/shared/user.h b/arch/um/include/shared/user.h
index 58c0581..4fa82c0 100644
--- a/arch/um/include/shared/user.h
+++ b/arch/um/include/shared/user.h
@@ -40,4 +40,7 @@
extern size_t strlcpy(char *, const char *, size_t);
extern size_t strlcat(char *, const char *, size_t);
+/* Copied from linux/compiler-gcc.h since we can't include it directly */
+#define barrier() __asm__ __volatile__("": : :"memory")
+
#endif