[Mesa-dev] [PATCH v2 5/7] disk cache: initialize cache path and index only when used

[Timothy Arceri]

On 09/02/18 14:45, Timothy Arceri wrote:
> On 08/02/18 16:36, Tapani Pälli wrote:
>> Hi;
>>
>> On 02/08/2018 06:00 AM, Timothy Arceri wrote:
>>> Hi Tapani,
>>>
>>> This patch causes deadlock when running piglit on my radeonsi with my 
>>> ryzen (16 threads all running shader_runner). Have you tested it on 
>>> similar Intel hardware?
>>
>> It passes Intel CI, not sure if that counts though. Can you send some 
>> more debug information?
> 
> Looking closer at this change I think it needs to be reverted. It's not 
> thread safe at all, applications are allowed to compile multiple 
> programs attached to the same context in different threads which means 
> we can end up with multiple threads inside disk_cache_path_init() at the 
> same time causing all sorts of problems. glthread, radeonsi threaded 
> compile, etc have the potential to hit this race condition even if the 
> app doesn't do threaded compiles.
> 
> I'm still not exactly sure why we must avoid creating the path in order 
> to use callbacks. Can you explain the issue you are trying to solve in 
> greater detail?

I've sent a series to revert things for now.

https://patchwork.freedesktop.org/series/37972/