Re: [PATCH 1/2] virtio-blk: set req->state to MQ_RQ_COMPLETE after polling I/O is finished

[Suwan Kim <suwan.kim027@gmail.com>]

On Sun, Dec 11, 2022 at 10:50:03PM -0800, Christoph Hellwig wrote:
> On Thu, Dec 08, 2022 at 09:48:23AM -0700, Jens Axboe wrote:
> > > The doc comment for blk_mq_set_request_complete() mentions this being
> > > used in ->queue_rq(), but that's not the case here. Does the doc comment
> > > need to be updated if we're using the function in a different way?
> > 
> > Looks like it's a bit outdated...
> 
> I think the comment is still entirely correct.
> 
> > 
> > > I'm not familiar enough with the Linux block APIs, but this feels weird
> > > to me. Shouldn't blk_mq_end_request_batch(iob) take care of this for us?
> > > Why does it set the state to IDLE instead of COMPLETE?
> > > 
> > > I think Jens can confirm whether we really want all drivers that use
> > > polling and io_comp_batch to manually call
> > > blk_mq_set_request_complete().
> > 
> > Should not be a need to call blk_mq_set_request_complete() directly in
> > the driver for this.
> 
> Exactly.  Polling or not, drivers should go through the normal completion
> interface, that is blk_mq_complete_request or the lower-level options
> blk_mq_complete_request_remote and blk_mq_complete_request_direct.

Hi all,

Thanks for the comment. It was the wrong use of the function...
I will use blk_mq_complete_request_remote() instead of
blk_mq_set_request_complete() and send next version soon.

Regards,
Suwan Kim