Meaning of: handle_workitem_freeblocks: block count

[Lucius Windschuh]

Hi.
I was using UFS2 with gjournal and now testing UFS2 with SUJ enabled,
on -CURRENT rr207195 (i386).
During some simple linear write tests with dd if=/dev/zero
of=/some/fs/file bs=1M, this message appeared in the kernel log:
Apr 28 12:24:15 current kernel: handle_workitem_freeblocks: block count

Some times, this messages also comes after the dd stopped and if I
remember right, in some cases also after running a background fsck on
an UFS2 with SU enabled:
Apr 25 22:51:31 t400 fsck: /dev/ada0s1d.eli: UNREF FILE I=4638583
OWNER=lw MODE=100644
Apr 25 22:51:31 t400 fsck: /dev/ada0s1d.eli: SIZE=56013 MTIME=Apr 25
22:39 2010  (CLEARED)
Apr 25 22:51:31 t400 fsck: /dev/ada0s1d.eli: UNREF FILE I=4638606
OWNER=lw MODE=100644
Apr 25 22:51:31 t400 fsck: /dev/ada0s1d.eli: SIZE=56013 MTIME=Apr 25
22:37 2010  (CLEARED)
Apr 25 22:51:31 t400 fsck: /dev/ada0s1d.eli: Reclaimed: 0 directories,
2 files, 54 fragments
Apr 25 22:51:31 t400 fsck: /dev/ada0s1d.eli: 254348 files, 10156202
used, 9195354 free (48682 frags, 2286668 blocks, 0.3% fragmentation)
Apr 25 22:51:43 t400 kernel: handle_workitem_freeblocks: block count

My kernel config is:
http://sites.google.com/site/lwfreebsd/Home/files/kernelconfig-T400.txt?attredirects=0&d=1

Can somebody explain the meaning of this message?
I saw that it was converted from a panic() to a diagnostic
notification in r68715 by Kirk McKusick.
A quick search showed that only a few people did encounter this
message over the years (perhaps because it is only visible with
INVARIANTS/DIAGNOSTIC enabled?).
Could indicate an hardware fault, even if my system runs stable?

Lucius