LU-9735 compat: heed the fs_struct::seq

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

diff --git a/lustre/autoconf/lustre-core.m4 b/lustre/autoconf/lustre-core.m4
index 5f50404..d260d08 100644 (file)
--- a/lustre/autoconf/lustre-core.m4
+++ b/lustre/autoconf/lustre-core.m4
@@ -612,6 +612,22 @@ kernel_locked, [
 ]) # LC_KERNEL_LOCKED
 
 #
+# LC_FS_STRUCT_SEQCOUNT
+#
+# 2.6.37 uses seqlock in fs_struct
+#
+AC_DEFUN([LC_FS_STRUCT_SEQCOUNT], [
+LB_CHECK_COMPILE([if fs_struct use seqcount],
+fs_struct_seqcount, [
+       #include <linux/fs_struct.h>
+],[
+       ((struct fs_struct *)0)->seq = (struct seqcount){ 0 };
+],[
+       AC_DEFINE(HAVE_FS_STRUCT_SEQCOUNT, 1, [fs_struct use seqcount])
+])
+]) # LC_FS_STRUCT_SEQCOUNT
+
+#
 # LC_D_COMPARE_7ARGS
 #
 # 2.6.38 dentry_operations.d_compare() taken 7 arguments.
@@ -2746,6 +2762,7 @@ AC_DEFUN([LC_PROG_LINUX], [
 
        # 2.6.37
        LC_KERNEL_LOCKED
+       LC_FS_STRUCT_SEQCOUNT
 
        # 2.6.38
        LC_BLKDEV_GET_BY_DEV