Paul Davis wrote: > >When an interrupt for MIDI input occurs, the hdsp driver disables all > >further MIDI interrupts until the current input data has been read. > > the hdsp driver is one of the first alsa drivers to use tasklets to > handle MIDI without impacting audio latency (that is, we can continue > processing audio i/o even while MIDI i/o is pending). once we have > launched a tasklet to handle MIDI input, there is no point handling > more interrupts that tell us the same thing. > > the tasklet stuff relies on the kernel scheduler, but AFAIK, the > tasklet effectively runs like the kernel equivalent of a SCHED_FIFO > thread. i don't know at what priority, however.
AFAIK tasklets have higher priority than any user thread. >From the error description I diagnose that either MIDI interrupts or the MIDI tasklet are suppressed while jack is running. It shouldn't be possible to prevent a tasklet from running unless the CPU usage is 100%, so I think it's somehow related to interrupts. Maybe the hardware doesn't set (or clears) the MIDI bit when too many PCM interrupts occur, but I'm just guessing here. Regards, Clemens ------------------------------------------------------- This sf.net email is sponsored by:ThinkGeek Welcome to geek heaven. http://thinkgeek.com/sf _______________________________________________ Alsa-devel mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/alsa-devel
