[alsa-devel] Still have choppy audio using 1.0.17

stan ghjeold_i_mwee at cox.net
Tue Jul 15 23:31:59 CEST 2008

Gustavo da Silva Serra wrote:
>> _______________________________________________
> It silences a whole period because the pointer inside aloop behaves like 
> that. Logging the pointer inside aloop I discovered that it is 
> incremented so fast inside timer function that when pointer function is 
> called, the pointer is not being incremented anymore. It is like a 
> concurrency issue: first the pointer will be incremented many times, 
> after that, the pointer function will be called many times with the same 
> pointer value. Later, the pointer will be incremented some more, and so 
> on...
> I wonder if this is not the problem, logging the pointer for my sound 
> card I see a different behavior: the pointer function return offset 
> between two periods.
> _______________________________________________

Sounds like this is a critical section that has no 
protection.  So the sequence is messed up.  In the 
regular sound card, there must be a semaphore or block 
to prevent this kind of behavior.  You could probably 
add the logic from the regular card to the aloop 
function and fix it.

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