[Intel-gfx] [PATCH 1/2] drm/i915: add module parameter compiler hints

[Ben Widawsky]

On Wed, Jul 06, 2011 at 04:03:14PM -0700, Keith Packard wrote:
> On Wed,  6 Jul 2011 15:14:52 -0700, Ben Widawsky <ben at bwidawsk.net> wrote:
> 
> 
> > -static int i915_modeset = -1;
> > +static int i915_modeset __read_mostly = -1;
> 
> What effect does this have? Performance? Code size? More warnings?

__read_mostly attempts to put variables in a cachelines to make it more
SMP friendly. I'm not sure if there is a performance impact as a result,
but made this patch based on feedback from Chris. I've seen no
regressions on Nexuiz.

The __always_unused I don't think has any real use other than
documentation. Potentially GCC could do something useful with it, but I
don't think it's enabled anywhere important.

Ben
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