Re: [patch] Real-Time Preemption, -RT-2.6.10-rc1-mm3-V0.7.25-1

From: Mark_H_Johnson
Date: Fri Nov 12 2004 - 13:27:42 EST

>Typical example of the error message:
>kernel: hde: dma_timer_expiry: dma status == 0x24
>kernel: ALSA sound/core/pcm_native.c:1424: playback drain error (DMA or
IRQ trouble?)
>kernel: PDC202XX: Primary channel reset.
>kernel: hde: DMA interrupt recovery
>kernel: hde: lost interrupt
>This was on a Promise TX2 133 ide card with one IDE disk. The problem
>would show itself if using the RT patches and APIC. But the problem seems
>to have been resolved now.

I had errors like that one when the IDE IRQ was at a priority less than
the real time task. Since then, I run with all the IRQ's at max RT priority
and will continue to do so until I get a better assessment of what my real
application (not these audio tests...) needs for IRQ priorities.

This may have been fixed as a side effect of Ingo setting the IRQ threads
RT priorities in the 40's.

--Mark H Johnson

To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at
Please read the FAQ at