Re: Re: USB recording - repetitive peaks

[Takashi Iwai <tiwai@suse.de>]

At Fri, 05 Jul 2002 02:15:39 +0900,
Patrick Shirkey wrote:
> 
> Takashi Iwai wrote:
> > At Fri, 05 Jul 2002 01:23:18 +0900,
> > Patrick Shirkey wrote:
> > 
> >>Takashi Iwai wrote:
> >>
> >> >the hang-up at capture close was at least fixed on cvs.
> >> >it was due to the combination of ASYNC_UNLINK and complete callbacks.
> >> >
> >> >not sure whether the bug with jack is fixed, too, but i think it was 
> >> >caused by the same reason.  please update the cvs tree.
> >>
> >>I can now record successfully using arecord without hanging the system
> >>but now I get an instant lock up while starting ardour. :( I have a 
> >>suspicion that it happens when ardour registers with jackd and asks for 
> >>the available input devices.  (I'm not sure about the sound quality. I 
> >>will see if I can generate a test tone to use instead of actual music).
> > 
> > 
> > then could you remove the mask USB_ASYNC_UNLINK from line 826 of
> > usbaudio.c? 
> > this might also leads to a lock-up when usb_submit_urb() fails, but
> > this must happen rarely.
> > 
> 
> First I tried
> 
> 		u->urb->transfer_flags = USB_ISO_ASAP; /*  |  USB_ASYNC_UNLINK; */
> 
> but that made almost no difference. I was able to load ardour for about 
> 10 seconds before the machine hung.

i (hopefully) found the spot.
it happend when snd_pcm_stop() is called during complete callbacks, so
the working urb won't be released properly.
now the fixed version is on cvs.


Takashi


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