[Mesa-dev] [PATCH 3/3] gallium/radeon: pass LLVM processor to the disk shader cache

[Nicolai Hähnle]

On 11.08.2017 20:37, Marek Olšák wrote:
> On Fri, Aug 11, 2017 at 6:00 PM, Nicolai Hähnle <nhaehnle at gmail.com> wrote:
>> On 10.08.2017 21:57, Marek Olšák wrote:
>>>
>>> From: Marek Olšák <marek.olsak at amd.com>
>>>
>>> ---
>>>    src/gallium/drivers/radeon/r600_pipe_common.c | 2 +-
>>>    1 file changed, 1 insertion(+), 1 deletion(-)
>>>
>>> diff --git a/src/gallium/drivers/radeon/r600_pipe_common.c
>>> b/src/gallium/drivers/radeon/r600_pipe_common.c
>>> index 95458d2e..0038c9a 100644
>>> --- a/src/gallium/drivers/radeon/r600_pipe_common.c
>>> +++ b/src/gallium/drivers/radeon/r600_pipe_common.c
>>> @@ -878,21 +878,21 @@ static void r600_disk_cache_create(struct
>>> r600_common_screen *rscreen)
>>>    #endif
>>>                  if (res != -1) {
>>>                          /* These flags affect shader compilation. */
>>>                          uint64_t shader_debug_flags =
>>>                                  rscreen->debug_flags &
>>>                                  (DBG_FS_CORRECT_DERIVS_AFTER_KILL |
>>>                                   DBG_SI_SCHED |
>>>                                   DBG_UNSAFE_MATH);
>>>                          rscreen->disk_shader_cache =
>>> -
>>> disk_cache_create(r600_get_family_name(rscreen),
>>> +
>>> disk_cache_create(r600_get_llvm_processor_name(rscreen->family),
>>
>>
>> What's the advantage of this?
> 
> It's added to the shader cache key. It allows shaders cached for
> Vega10 to be used by Raven and vice versa. Same for Polaris11 and
> Polaris12. It makes things nicer for some multi-GPU setups or when
> swapping GPUs.

I'm not a huge fan of this since the shader code does have access to the 
family, and there might be a need for family-specific workarounds. I'm 
actually not a huge fan of this overall, because the debug_flags thing 
seems flaky as well.

There's currently some corruption in Unigine demos which seems related 
to the shader cache, which just goes to show how difficult it is to 
really get this stuff right. I'd rather be on the safe side.

Cheers,
Nicolai

> 
> Marek
> 


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