Re: [PATCH 17/17] nvme: enable non-inline passthru commands

Kanchan Joshi
2022-04-19T17:32:17Z

Hi Jens,
Few thoughts below toward the next version -

On Fri, Apr 1, 2022 at 8:14 AM Jens Axboe <axboe@kernel.dk> wrote:
[snip]
> >>> Sure, will post the code with bigger-cqe first.
> >>
> >> I can add the support, should be pretty trivial. And do the liburing
> >> side as well, so we have a sane base.
> >
> > I will post the big-cqe based work today. It works with fio.
> > It does not deal with liburing (which seems tricky), but hopefully it
> > can help us move forward anyway .
>
> Let's compare then, since I just did the support too :-)

Major difference is generic support (rather than uring-cmd only) and
not touching the regular completion path. So plan is to use your patch
for the next version with some bits added (e.g. overflow-handling and
avoiding extra CQE tail increment). Hope that sounds fine.

We have things working on top of your current branch
"io_uring-big-sqe". Since SQE now has 8 bytes of free space (post
xattr merge) and CQE infra is different (post cqe-caching in ctx) -
things needed to be done a bit differently. But all this is now tested
better with liburing support/util (plan is to post that too).