Dne 19. 05. 20 v 15:46 Takashi Iwai napsal(a):
Because of these reasons I think it would be better to drop the lock-free implementation entirely and just use the existing non-concurrent architecture-independent implementation from pcm_dmix_generic.c. Aside from being faster, it would also eliminate a lot of architecture-dependent code and inline assembly. Should I submit a patch for this?
The advantage of lockless dmix implementation isn't about its CPU usage
but the nature where a stream isn't prevented by other streams, which
assures the very low latency, too. That is, with the generic dmix, a
stream can be still halted when another stream stalls in the middle,
and there is no way to recover from it.
So, IMO, we can start with a dynamic configuration to choose the
behavior and add a configure option to choose the implementations.
The default behavior should be still an open question, though.
I fully agree here.
Jaroslav
--
Jaroslav Kysela <perex@xxxxxxxx>
Linux Sound Maintainer; ALSA Project; Red Hat, Inc.
