Re: [Chromium-dev] Tee SPU

[Brian P. <br...@tu...>]

Keith Whitwell wrote:
> Karl Rasche wrote:
> 
>>> closely.  It seems to be implied that each time a spu is added to a 
>>> chain, a shared object is dlopen'ed, and that if you added the same 
>>> spu twice, this would cause a failure?
>>
>>
>>
>>> I don't understand why you'd ever need to load the same .so file 
>>> twice, unless you were relying on using static variables to store 
>>> state.  In which case, the 
>>
>>
>>
>> Not a failure per say, but the second spus config would clobber the 
>> first,
>> as, you correctly deduce, that the config state is static.
>>
>>> easiest answer would be to switch to malloc'ed state variables.  
>>> Loading the 
>>
>>
>>
>> Wouldn't you then have to 'keep track' of the malloced state someplace,
>> and which state goes with which instance, and get it back into the spu
>> when entering a function? 
> 
> 
> Yep, but you'd have to do something like this for threading support too, 
> wouldn't you?
> 
> Fast TLS is a GL prerequisite, it seems.

The problem isn't just threading.  Suppose you have two instances of the same 
"foobar" SPU in your SPU chain.  When you're in the foobarspu_Enable() 
function, how do you know which instance of SPU state to grab?

-Brian