[Mesa-dev] [PATCH] i965/fs: Disable opt_sampler_eot for more message types

[Matt Turner]

On Tue, Oct 20, 2015 at 11:57 AM, Matt Turner <mattst88 at gmail.com> wrote:
> On Tue, Oct 20, 2015 at 2:56 AM, Neil Roberts <neil at linux.intel.com> wrote:
>> In bfdae9149e0 I disabled the opt_sampler_eot optimisation for TG4
>> message types because I found by experimentation that it doesn't work.
>> I wrote in the comment that I couldn't find any documentation for this
>> problem. However I've now found the documentation and it has
>> additional restrictions on further message types so this patch updates
>> the comment and adds the others.
>> ---
>>
>> That paragraph in the spec also mentions further restrictions that we
>> should probably worry about like that the shader shouldn't combine
>> this optimisation with any other render target data port read/writes.
>>
>> It also has a fairly pessimistic note saying the optimisation is only
>> really good for large polygons in a GUI-like workload. I wonder
>> whether we should be doing some more benchmarking to decide whether
>> it's really a good idea to enable this as a general optimisation even
>> for games.
>
> That's frustrating. I wish the documentation would contain notes like
> this from the beginning, but maybe I should just be thankful that it
> includes that text at all.
>
> Both patches are
>
> Reviewed-by: Matt Turner <mattst88 at gmail.com>

Just this one actually. I thought it was part of a series.