On Mon, Mar 19, 2018 at 08:19:57PM -0700, Darrick J. Wong wrote: > On Mon, Mar 05, 2018 at 01:27:14PM -0800, Christoph Hellwig wrote: > > The upcoming aio poll support would like to be able to complete the > > iocb inline from the cancellation context, but that would cause > > a lock order reversal. Add support for optionally moving the cancelation > > outside the context lock to avoid this reversal. > > I started to wonder which lock order reversal the commit message refers > to? > > I think the reason for adding delayed cancellations is that we want to > be able to call io_cancel -> kiocb_cancel -> aio_poll_cancel -> > aio_complete without double locking ctx_lock? It is. I've updated the commit message.
