Re: [gentoo-dev] maintainer-wanted: x11-drivers/nvidia-drivers

[Walter Dnes]

On Tue, Mar 05, 2013 at 04:47:09PM +0800, Greg KH wrote
> On Tue, Mar 05, 2013 at 02:01:31AM -0500, Walter Dnes wrote:
> > On Mon, Mar 04, 2013 at 03:44:33PM -0100, Carlos Silva wrote
> > > On Mon, Mar 4, 2013 at 3:28 PM, Walter Dnes <waltdnes@××××××××.org> wrote:
> > >
> > > >   I'm not a C programmer, let alone a developer, so this may be a stupid
> > > > question, but here goes... has anyone ever tried doing a HAL (Hardware
> > > > Abstraction Layer) to present a reasonably stable interface to binary
> > > > video drivers?  Think of it as a shim translating a "pseudo-API" into
> > > > "the real API" that the kernel exposes directly.  Surely, we can do
> > > > better than VESA.  Give drivers 2 options...
> > > > 1) direct kernel access like now
> > > > 2) access via the HAL/shim
> > >
> > >
> > > Just read this file and you'll have the answer:
> > > /usr/src/linux/Documentation/stable_api_nonsense.txt
> >
> >   Thanks.  That was an eye-opener.  If user-space drivers are really
> > that slow, we may as well stick with VESA as a fallback.
>
> Ok, I'll bite, What do you mean by that?  Where does the
> stable_api_nonsense.txt file talk about userspace drivers?
>
> greg "I wrote that file" k-h

  My statement was a general response to the entire thread.  Sorry, I
should've retitled it [REDUX whatever] 

* stable_api_nonsense.txt explained lack of a stable *KERNEL* api

* Duncan's message talked about slow *USERSPACE* API...

> Of course it's possible to implement a userspace driver that
> wouldn't have the same issues as it'd use the stable userspace API,
> but that's generally accepted to be far too high a performance cost
> for graphics drivers, regardless of the kernel involved (MS tried
> it too for stability reasons and gave up at the performance penalty
> they were taking).

  So between your file, and Duncan's message, I saw that...
1) a stable kernel API is not possible
2) a userspace API is too slow.

  I apologize again for the vagueness in my previous reply.

-- 
Walter Dnes <waltdnes@××××××××.org>
I don't run "desktop environments"; I run useful applications