Hi,
I was checking some stuff relater to NO_PERIOD_WAKEUP and noticed that axfer has support for using either --sched-model=irq or --sched-model=timer. However from few quick tests it seems like it doesn't work?
$ aplay -l **** List of PLAYBACK Hardware Devices **** card 0: PCH [HDA Intel PCH], device 0: ALC283 Analog [ALC283 Analog] Subdevices: 1/1 Subdevice #0: subdevice #0
When using --sched-model=irq it transfers data until I press Ctrl+C
$ axfer transfer playback --sched-model=irq -D hw:0,0 -r 48000 -c2 -f S16_LE /dev/urandom PLAYBACK: Format 'Signed 16 bit Little Endian', Rate 48000 Hz, Channels 'Stereo' ^CPLAYBACK: Expected 4611686018427387903frames, Actual 163960frames Aborted by signal: Interrupt
However with --sched-model=timer it time outs by itself:
$ axfer transfer playback --sched-model=timer -D hw:0,0 -r 48000 -c2 -f S16_LE /dev/urandom PLAYBACK: Format 'Signed 16 bit Little Endian', Rate 48000 Hz, Channels 'Stereo' Fail to process frames: Connection timed out PLAYBACK: Expected 4611686018427387903frames, Actual 16304frames
How well is NO_PERIOD_WAKEUP tested/supported? Is it a bug in axfer or perhaps some issue in kernel code?
From some debugging I did, I have my suspicions that it gets stuck on poll in: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/soun... waiting for runtime->sleep to wake it, but seems like it never happens.
What do you think?
Amadeusz