[Mesa-dev] [RFC PATCH] gallium: add a common uploader to pipe_context

[Marek Olšák]

On Fri, Feb 3, 2017 at 9:45 PM, Brian Paul <brianp at vmware.com> wrote:
> On 02/01/2017 02:23 PM, Brian Paul wrote:
>>
>> On 01/27/2017 04:00 AM, Marek Olšák wrote:
>>>
>>> On Fri, Jan 27, 2017 at 10:05 AM, Nicolai Hähnle <nhaehnle at gmail.com>
>>> wrote:
>>>>
>>>> On 27.01.2017 00:51, Marek Olšák wrote:
>>>>>
>>>>>
>>>>> From: Marek Olšák <marek.olsak at amd.com>
>>>>>
>>>>> For lower memory usage and more efficient updates of the buffer
>>>>> residency
>>>>> list. (e.g. if drivers keep seeing the same buffer for many consecutive
>>>>> "add" calls, the calls can be turned into no-ops trivially)
>>>>
>>>>
>>>>
>>>> This makes sense to me, but how are you planning to deal with the bind
>>>> flags? They are currently set differently for different upload mgrs. We
>>>> should probably do away with them entirely anyway.
>>>
>>>
>>> Drivers can set the bind flags they need. Some drivers will set all 3
>>> bind flags. Other drivers don't have to set any.
>>
>>
>> I need to look into this part more closely.  I think we may have trouble
>> mixing constants with index/vertex data in our VMware driver...
>
>
> Marek,
>
> Your patch series, as-is, did indeed cause trouble with our VMware driver.
> We need to keep constants in a separate buffer.
>
> The good news is I don't think this is a huge problem and I've updated (a
> subset of) your patches to accommodate both your needs and ours.
>
> The basic idea is to add a pipe_context::get_stream_uploader() hook that
> allows drivers to use just one or separate uploaders for
> vertex/index/constant data.  Plus, I added a
> pipe_context::unmap_stream_uploaders() helper, but this isn't strictly
> necessary.
>
> WIP patch attached (only lightly tested).  Let me know what you think.

Can we simply add these 2 fields into pipe_context instead of the callback?

pipe_context::stream_uploader // vertex + index
pipe_context::const_uploader

Marek