On Wed, Aug 21, 2024 at 05:15:00PM +0300, Mathias Nyman wrote:
> My best guess is that these are caused by a full xhci event ring.
>
> If event ring is full it would stop transfer rings, and we would see
> missed service events. This matches the logs.
>
> The events get handled and cleared in the interrupt handler, but
> not every event generates an interrupt. for isoc transfers we
intentionally
> block a lot of event triggered interrupts.
This has piqued my interest. Can you point me to the code in the kernel
source where this filtering happens?
> The event ring size has doubled since 6.6.45 kernel, using a newer kernel
> could help. This changed in 6.7 kernel:
> 28084d3fcc3c ("xhci: Use more than one Event Ring segment")
I tried with a 6.10.6 kernel from archlinux and the symptoms didnt'
change. Right now I'm running 6.7.0.6.realtime1-7-rt from archlinux and
the symptoms are also the same.
> If possible I'd like to see xhci traces of this issue.
Here is a curl'able trace (from running timeout -s KILL 0.1 jackd -R -P
70 -d alsa -d hw:USB -p 48 -n 2 (thanks to Michal for the suggestion)):
https://uni-bielefeld.sciebo.de/s/1ixBodEpmSg8M2k/download
Or should I include it inline (it's ca. 1M.)
Kind regards,
FPS
