On Wed, Aug 21, 2019 at 09:00:37AM -0700, Tejun Heo wrote:

quoted

2) When you invalidate frn entry here by writing 0 to 'at', it's likely to get
reused soon. Possibly while the writeback is still running. And then you
won't start any writeback for the new entry because of the
atomic_read(&frn->done.cnt) == 1 check. This seems like it could happen
pretty frequently?

Hmm... yeah, the clearing might not make sense.  I'll remove that.

Oh, the reuse logic checks whether done.cnt == 1 and only reuse if no
writeback is still in flight, so this one should be fine.

Thanks.

-- 
tejun