Re: [PATCH 28/32] aio: simplify cancellation

Christoph Hellwig [off-list ref] writes:

With the current aio code there is no need for the magic KIOCB_CANCELLED
value, as a cancelation just kicks the driver to queue the completion
ASAP, with all actual completion handling done in another thread. Given
that both the completion path and cancelation take the context lock there
is no need for magic cmpxchg loops either.

The cmpxchg was made unnecessary when the complementary xchg was removed
in commit bec68faaf ("aio: io_cancel() no longer returns the io_event").
There was no longer a need to ensure only the completion path or the
cancellation path delivered the completion event.  Now, the completion
is always delivered via aio_complete.

So yeah, we can get rid of this.

Acked-by: Jeff Moyer <redacted>