[Mesa-dev] [PATCH 7/7] android: set '/sdcard/' as MESA_GLSL_CACHE_DIR by default

[Tapani Pälli]

On 01/19/2018 01:03 PM, Tapani Pälli wrote:
> 
> 
> On 01/19/2018 11:22 AM, Jordan Justen wrote:
>> On 2018-01-18 22:08:17, Tapani Pälli wrote:
>>>
>>>
>>> On 01/18/2018 08:18 PM, Jordan Justen wrote:
>>>> On 2018-01-15 04:31:43, Tapani Pälli wrote:
>>>>> This can/should be modified depending on needs. AFAIK by default,
>>>>> this is the only path that can be read/written to by anyone.
>>>>>
>>>>> Signed-off-by: Tapani Pälli <tapani.palli at intel.com>
>>>>> ---
>>>>>    Android.common.mk | 1 +
>>>>>    1 file changed, 1 insertion(+)
>>>>>
>>>>> diff --git a/Android.common.mk b/Android.common.mk
>>>>> index 52dc7bff3b..7edbbfc0f2 100644
>>>>> --- a/Android.common.mk
>>>>> +++ b/Android.common.mk
>>>>> @@ -47,6 +47,7 @@ LOCAL_CFLAGS += \
>>>>>    LOCAL_CFLAGS += \
>>>>>           -DANDROID_API_LEVEL=$(PLATFORM_SDK_VERSION) \
>>>>>           -DENABLE_SHADER_CACHE \
>>>>> +       -DMESA_GLSL_CACHE_DIR="/sdcard" \
>>>>
>>>> Is this used when EGL_ANDROID_blob_cache is being used?
>>>>
>>>> My thought is that if we are running under android with
>>>> EGL_ANDROID_blob_cache, then we should never attempt to write any
>>>> files with src/util/disk_cache.c. This might cause a little rework,
>>>> since the shader cache want to write/manage the index file, but can we
>>>> skip this and only use the blob cache read/write function when
>>>> EGL_ANDROID_blob_cache is available?
>>>
>>> I'm a bit pessimistic about that. Since cache location depends on
>>> running app that would mean every app has it's own index (that not
>>> really a problem though but is different from desktop).
>>
>> I suspect that the blob_cache is app specific. Therefore it also makes
>> sense that the index would be app specific.
>>
>>> The big problem I see there that index will be then 'just another
>>> cache entry', I'll have to get more familiar with Android's
>>> implementation to see if there would be way to make this entry
>>> 'special' so that it would not touch it.
>>
>> My suggestion was that we should scrap the index entirely when in
>> EGL_ANDROID_blob_cache mode. Essentially the Android OS is managing
>> the cache index for us, so hopefully we don't need to maintain one.
> 
> One issue to tackle is that currently _mesa_glsl_compile_shader uses 
> disk_cache_has_key() for detecting if we can skip shader compilation. 
> This uses 'stored_keys' which is mmap of the index file.
> 
> I guess this could be done by inserting items for those shaders to 
> blob_cache so disk_cache_has_key() could use get() for implementing this 
> functionality. It seemed easier (and more optimal) to go with existing 
> 'index' for this but I can try alternative approach also.

So maybe to further summarize, I wanted to use existing codebase as much 
as is but I'll try implementing has_key and put_key separately for 
blob_cache.

Thanks;

// Tapani