On Tue, Feb 21, 2017 at 05:49:02PM +0200, Elena Reshetova wrote:
> @@ -1684,10 +1684,11 @@ xfs_buftarg_isolate(
> * zero. If the value is already zero, we need to reclaim the
> * buffer, otherwise it gets another trip through the LRU.
> */
> - if (!atomic_add_unless(&bp->b_lru_ref, -1, 0)) {
> + if (!refcount_read(&bp->b_lru_ref)) {
> spin_unlock(&bp->b_lock);
> return LRU_ROTATE;
> }
> + refcount_dec_and_test(&bp->b_lru_ref);
>
> bp->b_state |= XFS_BSTATE_DISPOSE;
> list_lru_isolate_move(lru, item, dispose);
This should never have passed testing.. refcount_dec_and_test() has a
__must_check.
Furthermore the above seems to suggest thingies can live with a 0
refcount, so a straight conversion cannot work.
