[Mesa-dev] [PATCH] i965: Cache register write capability checks.

[Daniel Vetter]

On Mon, Dec 22, 2014 at 05:50:33PM -0800, Ben Widawsky wrote:
> On Mon, Dec 22, 2014 at 01:28:32AM -0800, Kenneth Graunke wrote:
> > Our ability to perform register writes depends on the hardware and
> > kernel version.  It shouldn't ever change on a per-context basis,
> > so we only need to check once.
> 
> That's actually not true. The kernel currently supports dynamic changes of the
> module parameter for the command parser. Because of that, and the fact that this
> improves one very synthetic microbench, in a perfect world we'd not merge this
> patch. However, I live in the real world, so maybe just add a comment that you
> can potentially shoot yourself in the foot if you change the module parameter in
> a running system, and then it's

We've gone over to pretty aggressively mark module options as _debug which
taints the kernel. Users really never should touch them (expect when we
ask them to for debugging), developers know what might happen. So fully
agreed that hurt feet aren't a concern here.
-Daniel
-- 
Daniel Vetter
Software Engineer, Intel Corporation
+41 (0) 79 365 57 48 - http://blog.ffwll.ch