UBIFS: fix shrinker object count reports
commit
cf610bf4199770420629d3bc273494bd27ad6c1d upstream.
Sometimes VM asks the shrinker to return amount of objects it can shrink,
and we return the ubifs_clean_zn_cnt in that case. However, it is possible
that this counter is negative for a short period of time, due to the way
UBIFS TNC code updates it. And I can observe the following warnings sometimes:
shrink_slab: ubifs_shrinker+0x0/0x2b7 [ubifs] negative objects to delete nr=-
8541616642706119788
This patch makes sure UBIFS never returns negative count of objects.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>