LU-13783 osc: handle removal of NR_UNSTABLE_NFS

[fs/lustre-release.git] / libcfs / autoconf / lustre-libcfs.m4

diff --git a/libcfs/autoconf/lustre-libcfs.m4 b/libcfs/autoconf/lustre-libcfs.m4
index dcf8028..529b534 100644 (file)
--- a/libcfs/autoconf/lustre-libcfs.m4
+++ b/libcfs/autoconf/lustre-libcfs.m4
@@ -1289,6 +1289,29 @@ cache_detail_writers_atomic, [
 EXTRA_KCFLAGS="$tmp_flags"
 ]) # LIBCFS_CACHE_DETAIL_WRITERS
 
+#
+# LIBCFS_HAVE_NR_UNSTABLE_NFS
+#
+# kernel v5.8-rc1~201^2~75
+# mm/writeback: discard NR_UNSTABLE_NFS, use NR_WRITEBACK instead
+#
+AC_DEFUN([LIBCFS_HAVE_NR_UNSTABLE_NFS], [
+tmp_flags="$EXTRA_KCFLAGS"
+EXTRA_KCFLAGS="-Werror"
+LB_CHECK_COMPILE([if NR_UNSTABLE_NFS still in use],
+nr_unstable_nfs_exists, [
+       #include <linux/mm.h>
+
+       int i;
+],[
+       i = NR_UNSTABLE_NFS;
+],[
+       AC_DEFINE(HAVE_NR_UNSTABLE_NFS, 1,
+               [NR_UNSTABLE_NFS is still in use.])
+])
+EXTRA_KCFLAGS="$tmp_flags"
+]) # LIBCFS_HAVE_NR_UNSTABLE_NFS
+
 AC_DEFUN([LIBCFS_PROG_LINUX_SRC], [] )
 AC_DEFUN([LIBCFS_PROG_LINUX_RESULTS], [])
 
@@ -1396,6 +1419,7 @@ LIBCFS_GET_REQUEST_KEY_AUTH
 LIBCFS_LOOKUP_USER_KEY
 LIBCFS_FORCE_SIG_WITH_TASK
 LIBCFS_CACHE_DETAIL_WRITERS
+LIBCFS_HAVE_NR_UNSTABLE_NFS
 ]) # LIBCFS_PROG_LINUX
 
 #