Re: serialize access to ide device

[Jens Axboe <axboe@suse.de>]

On Sat, Aug 21 2004, Bartlomiej Zolnierkiewicz wrote:
> On Saturday 21 August 2004 18:21, Jens Axboe wrote:
> > On Sat, Aug 21 2004, Bartlomiej Zolnierkiewicz wrote:
> > > On Saturday 21 August 2004 12:32, Jens Axboe wrote:
> > > > > What about adding new kind of REQ_SPECIAL request and converting
> > > > > set_using_dma(), set_xfer_rate(), ..., to be callback functions for
> > > > > this request?
> > > > >
> > > > > This should be a lot cleaner and will cover 100% cases.
> > > >
> > > > That will still only serialize per-channel. But yes, a lot cleaner.
> > >
> > > per hwgroup not per channel
> > > (serializing per host device will be better but requires even more work)
> >
> > Sorry yes hwgroup, that's what I meant. The case I worried about in my
> > patch (and noted) is that it doesn't cover per-hwif and neither would a
> > special request.
> 
> I guess you meant 'per-host' because hwif == channel.
> 
> [ You are of course right for about 'per-host' case. ]

Yep, per host. So REQ_SPECIAL-like approach is cleaner, but doesn't
cover more cases than a simple hwif pinning would anyways. You'd need
some code to quisce the host in any case.

-- 
Jens Axboe