mesa3d-dev

[Mesa3d-dev] [PATCHes] RFC: detect TLS during configuration

[tom f. <tf...@al...>]

It was a long while back that I wondered && somehow ended up
volunteering to detect platform TLS support, + enable it in Mesa / the
X server if available.

I got distracted before finishing the X parts, but rebased the Mesa
parts, which are attached.

One thing I'm worried about is using an AC macro archive macro here;
it's GPL + an exception that "configure" (the output) is unrestricted.
I'm not sure that'll be kosher for Mesa.

OTOH, the macro is dead simple.

Comments?

-tom

Re: [Mesa3d-dev] [PATCHes] RFC: detect TLS during configuration

[Dan N. <dbn...@gm...>]

On Sun, Mar 14, 2010 at 5:38 PM, tom fogal <tf...@al...> wrote:
> It was a long while back that I wondered && somehow ended up
> volunteering to detect platform TLS support, + enable it in Mesa / the
> X server if available.
>
> I got distracted before finishing the X parts, but rebased the Mesa
> parts, which are attached.
>
> One thing I'm worried about is using an AC macro archive macro here;
> it's GPL + an exception that "configure" (the output) is unrestricted.
> I'm not sure that'll be kosher for Mesa.

I don't think license of the build files affects the license of the
code. We're already using lots of macros from autoconf that are almost
certainly GPL.

> OTOH, the macro is dead simple.
>
> Comments?

I think I'd prefer if you added the macro directly to acinclude.m4
instead of adding more macro files. If we're going to do that, I'd
rather have an explicit m4 directory. I don't think mesa quite needs
that, though.

Changing TLS to autodetect might be a good thing down the road, but I
think we need to at least have the xserver following the settings
before we make this change. Otherwise, nearly everybody is suddenly
going to get TLS enabled in the DRI drivers who don't know they need
to start passing another option to the xserver.

So, I'd rather see these two patches broken up differently.

1. Export glx_tls from gl.pc
2. Autodetect TLS usage

Then we can hold off applying 2 until we have the xserver part landed
and we think it's safe to start defaulting (essentially) to using TLS.

--
Dan

Re: [Mesa3d-dev] [PATCHes] RFC: detect TLS during configuration

[tom f. <tf...@al...>]

Dan Nicholson <dbn...@gm...> writes:
> On Sun, Mar 14, 2010 at 5:38 PM, tom fogal <tf...@al...> wrote:
> > [I] volunteer[ed] to detect platform TLS support, + enable it in
> > Mesa / the X server if available.
> >
> > One thing I'm worried about is using an AC macro archive macro here;
> > it's GPL + an exception [. . .]
> 
> I don't think license of the build files affects the license of the
> code. We're already using lots of macros from autoconf that are almost
> certainly GPL.

Okay, great.

> > OTOH, the macro is dead simple.
> >
> > Comments?
> 
> I think I'd prefer if you added the macro directly to acinclude.m4
> instead of adding more macro files. If we're going to do that, I'd
> rather have an explicit m4 directory. I don't think mesa quite needs
> that, though.

Okay, I can integrate it directly.

> Changing TLS to autodetect might be a good thing down the road, but
> I think we need to at least have the xserver following the settings
> before we make this change. Otherwise, nearly everybody is suddenly
> going to get TLS enabled in the DRI drivers who don't know they need
> to start passing another option to the xserver.

Ahh, I see my memory was wrong; I figured a TLS driver could be used
regardless.  Digging up the old thread [1], it seems like it'd be
possible, but currently not implemented as such.

So, yes, I agree, autodetection shouldn't be applied until the X server
keys into it.

> So, I'd rather see these two patches broken up differently.
> 
> 1. Export glx_tls from gl.pc
> 2. Autodetect TLS usage

Will do.

-tom

[1] http://lists.x.org/archives/xorg-devel/2009-November/003411.html