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Message-ID: <39FDC447.C5DD7864@mandrakesoft.com>
Date: Mon, 30 Oct 2000 13:56:07 -0500
From: Jeff Garzik <jgarzik@mandrakesoft.com>
Organization: MandrakeSoft
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To: Christoph Hellwig <hch@caldera.de>
CC: Linus Torvalds <torvalds@transmeta.com>, linux-kernel@vger.kernel.org,
        sct@redhat.com
Subject: Re: [PATCH] kiobuf/rawio fixes for 2.4.0-test10-pre6
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Christoph Hellwig wrote:
> On Mon, Oct 30, 2000 at 12:19:21PM -0500, Jeff Garzik wrote:
> > Take a look at drivers/sound/via82cxxx_audio.c.  How can that mmap be
> > improved by using kiobufs?
> 
> I think so - but you need Stephen's kvmap patch, that is in the same
> patchset the forward-ported fixes are
> (at ftp://ftp.linux.org.uk/pub/linux/sct/fs/raw-io/)
> 
> An very nice example is included.

Seen it, re-read my question...

I keep seeing "audio drivers' mmap" used a specific example of a place
that would benefit from kiobufs.  The current via audio mmap looks quite
a bit like mmap_kiobuf and its support code... except without all the
kiobuf overhead.

My question from above is:  how can the via audio mmap in test10-preXX
be improved by using kiobufs?  I am not a kiobuf expert, but AFAICS a
non-kiobuf implementation is better for audio drivers.  (and the via
audio mmap implementation is what some other audio drivers are about to
start using...)

I can clearly see that many applications will find kiobufs quite useful
(learned another from alan just now...), but I do not see that audio
drivers can benefit from kiobufs at all.  Corrections on this fact are
requested, as I am hacking audio drivers right now and want to make sure
I pick the best course of action for the long term.

Regards,

	Jeff


-- 
Jeff Garzik             | "Mind if I drive?"  -Sam
Building 1024           | "Not if you don't mind me clawing at the
MandrakeSoft            |  dash and shrieking like a cheerleader."
                        |                     -Max
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