[alsa-devel] [PATCH 2/6] pcm:direct: fix race on clearing timer events

[Takashi Iwai]

On Fri, 17 Feb 2017 08:15:56 +0100,
sutar.mounesh at gmail.com wrote:
> 
> From: Andreas Pape <apape at de.adit-jv.com>
> 
> snd_timer handling is racy: plugins clear timer queue if avail_min
> is not reached to force a sleep on timer. The race can happen if
> the expected event arrives in between the avail check and the
> clearing of pending events. If this race happens, the user will
> unnecessarily wait for one more timer event. On low latency/realtime
> streams this can lead to xruns and must be avoided.
> 
> As a fix we recheck avail after having cleared poll events.
> 
> Signed-off-by: Andreas Pape <apape at de.adit-jv.com>
> Signed-off-by: Jiada Wang <jiada_wang at mentor.com>
> Signed-off-by: Mounesh Sutar <sutar.mounesh at gmail.com>

Applied, thanks.


Takashi