On Thu, May 13, 2021 at 03:37:02PM +0200, Amadeusz Sławiński wrote: > On 5/13/2021 3:25 PM, Takashi Sakamoto wrote: > > Hi, > > > > On Thu, May 13, 2021 at 01:34:25PM +0200, Amadeusz Sławiński wrote: > > > 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/sound/core/pcm_native.c?id=c06a2ba62fc401b7aaefd23f5d0bc06d2457ccc1#n3489 > > > waiting for runtime->sleep to wake it, but seems like it never happens. > > > > > > What do you think? > > > > It's a regression added by a commit e5e6a7838b06 ("axfer: return ETIMEDOUT > > when no event occurs after waiter expiration"), and the -ETIMEDOUT come > > neither from ALSA PCM core nor alsa-lib. Thanks for your reporting! > > > > * https://github.com/alsa-project/alsa-utils/commit/e5e6a7838b06 > > > > As a quick fix, please revert the commit. I'll post better fixes later. > > > > After the revert, it looks work well under my hardware: > > > > Yes, I can confirm, that it fixes the problem. Thanks for quick workaround! That's good. I just filed the better fix. Please apply it with your local repository instead of the revert patch. * alsa-utils: axfer: fix regression of timeout in timer-based scheduling model #88 * https://github.com/alsa-project/alsa-utils/pull/88 Anyway, thank you for reporting the bug. In recent years I've been working for devices in which no-period-wakeup is unavailable, so I overlooked the bug so long... Thanks Takashi Sakamoto
