[alsa-devel] 2.6.30: xruns caused by "ALSA: pcm - Safer boundary checks"

[Robert Krakora]

On Sat, May 23, 2009 at 2:22 PM, Takashi Iwai <tiwai at suse.de> wrote:
> At Sat, 23 May 2009 14:31:57 +0200 (CEST),
> Jaroslav Kysela wrote:
>>
>> On Fri, 22 May 2009, Takashi Iwai wrote:
>>
>> > At Fri, 22 May 2009 16:27:09 -0400,
>> > Chuck Ebbert wrote:
>> >>
>> >> Bug report: https://bugzilla.redhat.com/show_bug.cgi?id=498858
>> >>
>> >> To reproduce, pause a video in mplayer and then hit play:
>> >>
>> >> ALSA sound/core/pcm_lib.c:263: hda_codec: hw_ptr skipping! [Q] (pos=11263,
>> >> delta=17400, period=1024, jdelta=21/362/0)
>> >
>> > Does the patch fix the problem?
>>
>> This patch does not look as a proper fix.
>
> Hm, at which point?
> It just skips the first unreliable jiffies check.
> At least, it's interesting whether it works around the problem.
>
>
> thanks,
>
> Takashi
> _______________________________________________
> Alsa-devel mailing list
> Alsa-devel at alsa-project.org
> http://mailman.alsa-project.org/mailman/listinfo/alsa-devel
>
>

Takashi:

I have submitted
https://bugtrack.alsa-project.org/alsa-bug/view.php?id=4523 in regards
to this problem.  I can recreated the xrun messages 100% of the time
and the routine in question never recovers.  With a workaround
suggested by Jaroslav, the xruns go away, but the calling process
ramps up to 100% CPU utilization and unless you are on a dual or quad
core machine there is quite a lockup.  I revert to the 1.0.19 pcmlib.c
in the 1.0.20 driver and I see neither problem.  Thanks for all of
your help Jaroslav.  If there is any way that I can help debug this
problem, please let me know.

Best Regards,

-- 
Rob Krakora
Senior Software Engineer
MessageNet Systems
101 East Carmel Dr. Suite 105
Carmel, IN 46032
(317)566-1677 Ext. 206
(317)663-0808 Fax