+# vfs_symlink seems to have started out with 3 args until 2.6.7 where a
+# "mode" argument was added, but then again, in some later version it was
+# removed
+AC_DEFUN([LC_4ARGS_VFS_SYMLINK],
+[AC_MSG_CHECKING([if vfs_symlink wants 4 args])
+LB_LINUX_TRY_COMPILE([
+ #include <linux/fs.h>
+],[
+ struct inode *dir;
+ struct dentry *dentry;
+ const char *oldname = NULL;
+ int mode = 0;
+
+ vfs_symlink(dir, dentry, oldname, mode);
+],[
+ AC_MSG_RESULT(yes)
+ AC_DEFINE(HAVE_4ARGS_VFS_SYMLINK, 1,
+ [vfs_symlink wants 4 args])
+],[
+ AC_MSG_RESULT(no)
+])
+])
+
+# Ensure stack size big than 8k in Lustre server
+AC_DEFUN([LC_STACK_SIZE],
+[AC_MSG_CHECKING([stack size big than 8k])
+LB_LINUX_TRY_COMPILE([
+ #include <linux/thread_info.h>
+],[
+ #if THREAD_SIZE < 8192
+ #error "stack size < 8192"
+ #endif
+],[
+ AC_MSG_RESULT(yes)
+],[
+ AC_MSG_ERROR([Lustre requires that Linux is configured with at least a 8KB stack.])
+])
+])
+