On Wed, Oct 10, 2012 at 06:07:24PM +0800, zwu.kernel@gmail.com wrote:

+void hot_track_init(struct super_block *sb)
+{

...

+}

+void hot_track_exit(struct super_block *sb)
+{
+	hot_cache_exit();
+}

Needs to be exported if btrfs is built as a module, otherwise does not
link

  LDS     arch/x86/boot/compressed/vmlinux.lds
  AS      arch/x86/boot/compressed/head_64.o
  CC      arch/x86/boot/compressed/misc.o
  CC      arch/x86/boot/compressed/string.o
  CC      arch/x86/boot/compressed/cmdline.o
  CC      arch/x86/boot/compressed/early_serial_console.o
  OBJCOPY arch/x86/boot/compressed/vmlinux.bin
ERROR: "hot_track_init" [fs/btrfs/btrfs.ko] undefined!
ERROR: "hot_track_exit" [fs/btrfs/btrfs.ko] undefined!
make[1]: *** [__modpost] Error 1
make: *** [modules] Error 2
make: *** Waiting for unfinished jobs....


david