Re: Playing with SATA NCQ

[Jens Axboe <axboe@suse.de>]

On Fri, May 27 2005, Jeff Garzik wrote:
> Jens Axboe wrote:
> >Yeah, I'm not a huge fan of the need for the above code... If every qc
> >was tied to a SCSI command, we could just ask for a later requeue of the
> >request as is currently done with NCQ commands. Alternatively, we could
> >add an internal libata qc queue for postponing these commands. That
> >would take a little effort, as the sync errors reported by
> >ata_qc_issue() would then be need to signalled async through the
> >completion callback instead.
> >
> >Jeff, what do you think?
> 
> Just use the SCSI layer for requeueing.  That's what I intended.

Yep, that is what I'm doing for SCSI originated commands.

> Every qc that matters can be requeued.  Just don't worry about
> non-queued, non-fast-path commands.  They are typically used in
> functions that will immediately notice a failure, and handle it
> accordingly.

So the current wait-around stuff is ok with you?

-- 
Jens Axboe