On 24/11/11 02:52, Steven Rostedt wrote:
On Thu, 2011-11-24 at 01:39 +1300, Chris Edwards wrote:
Hi all,
Problem:
IRQ-related "nobody cared" kernel call traces not long after bootup on
Linux 3.0.10-rt27. I thought I'd try a -rt kernel to see if it would
resolve the audio drop-outs on my new Firewire audio interface.
I wonder if this is another bad irq chipset. Does it go away if you boot
with noapic in the kernel command line?
Thanks for the quick reply, Steven. Booting with "noapic" does seem to
avoid the problem with IRQs 17 and 18, and the Firewire audio now works,
but the "nobody cared" error now appears for IRQ 7:
[ 752.450644] irq 7: nobody cared (try booting with the "irqpoll" option)
[ 752.450653] Pid: 74, comm: irq/7-ohci_hcd: Not tainted 3.0.10-rt27 #1
[ 752.450657] Call Trace:
[ 752.450671] [<ffffffff810c315a>] __report_bad_irq+0x3a/0xd0
[ 752.450676] [<ffffffff810c3332>] note_interrupt+0x142/0x1f0
[ 752.450680] [<ffffffff810c2e16>] irq_thread+0x1b6/0x1e0
[ 752.450684] [<ffffffff810c2f10>] ? exit_irq_thread+0x80/0x80
[ 752.450688] [<ffffffff810c2c60>] ? irq_finalize_oneshot+0x130/0x130
[ 752.450692] [<ffffffff810c2c60>] ? irq_finalize_oneshot+0x130/0x130
[ 752.450699] [<ffffffff81081876>] kthread+0x96/0xa0
[ 752.450703] [<ffffffff8104dda2>] ? finish_task_switch+0x52/0x100
[ 752.450711] [<ffffffff815f09e4>] kernel_thread_helper+0x4/0x10
[ 752.450715] [<ffffffff810817e0>] ? kthreadd+0x170/0x170
[ 752.450719] [<ffffffff815f09e0>] ? gs_change+0x13/0x13
[ 752.450721] handlers:
[ 752.450726] [<ffffffff810c1760>] irq_default_primary_handler threaded
[<ffffffff81464e60>] usb_hcd_irq
[ 752.450733] Disabling IRQ #7
Here is the interrupt arrangement now:
cat /proc/interrupts
CPU0 CPU1
0: 125 0 XT-PIC-XT-PIC timer
1: 2 0 XT-PIC-XT-PIC i8042
2: 0 0 XT-PIC-XT-PIC cascade
3: 1 0 XT-PIC-XT-PIC
4: 1 0 XT-PIC-XT-PIC
5: 4794 279 XT-PIC-XT-PIC ehci_hcd:usb1
6: 4 1 XT-PIC-XT-PIC floppy
7: 2071 16855 XT-PIC-XT-PIC ohci_hcd:usb3
8: 0 0 XT-PIC-XT-PIC rtc0
9: 295 18 XT-PIC-XT-PIC acpi, sata_nv, ohci_hcd:usb2
10: 9995 1467 XT-PIC-XT-PIC sata_sil, Gina24
11: 1758 305 XT-PIC-XT-PIC megaraid, aic7xxx,
firewire_ohci, eth1, aic7xxx
12: 4 0 XT-PIC-XT-PIC i8042
14: 0 0 XT-PIC-XT-PIC pata_amd
15: 0 0 XT-PIC-XT-PIC pata_amd
NMI: 2 2 Non-maskable interrupts
LOC: 39580 37870 Local timer interrupts
SPU: 0 0 Spurious interrupts
PMI: 2 2 Performance monitoring interrupts
IWI: 0 0 IRQ work interrupts
RES: 12595 17142 Rescheduling interrupts
CAL: 4611 2901 Function call interrupts
TLB: 264 285 TLB shootdowns
TRM: 0 0 Thermal event interrupts
THR: 0 0 Threshold APIC interrupts
MCE: 0 0 Machine check exceptions
MCP: 21 21 Machine check polls
ERR: 34
MIS: 0
Looking at the interrupt rates while running jackd with different
settings, it looks a lot like the Firewire interrupts are being
duplicated on IRQ 7. Also (and I'm not sure if this is significant) the
interrupt rates seem to be swapped with respect to the CPUs:
IRQ 7 on CPU 0 (ohci_hcd:usb3) shows essentially the same rate as IRQ 11
on CPU 1 (megaraid, aic7xxx, firewire_ohci, eth1, aic7xxx).
IRQ 7 on CPU 1 (ohci_hcd:usb3) ditto WRT IRQ 11 on CPU 0 (megaraid,
aic7xxx, firewire_ohci, eth1, aic7xxx)
Here are the interrupt stats after that testing - you can see the
relationship between IRQs 7 and 11 and the ERR (and, I just noticed,
also the RES) counts.
cat /proc/interrupts
CPU0 CPU1
0: 125 0 XT-PIC-XT-PIC timer
1: 2 0 XT-PIC-XT-PIC i8042
2: 0 0 XT-PIC-XT-PIC cascade
3: 1 0 XT-PIC-XT-PIC
4: 1 0 XT-PIC-XT-PIC
5: 4794 279 XT-PIC-XT-PIC ehci_hcd:usb1
6: 4 1 XT-PIC-XT-PIC floppy
7: 1110109 5323192 XT-PIC-XT-PIC ohci_hcd:usb3
8: 0 0 XT-PIC-XT-PIC rtc0
9: 28893 5605 XT-PIC-XT-PIC acpi, sata_nv, ohci_hcd:usb2
10: 25475 2831 XT-PIC-XT-PIC sata_sil, Gina24
11: 5264022 1101395 XT-PIC-XT-PIC megaraid, aic7xxx,
firewire_ohci, eth1, aic7xxx
12: 4 0 XT-PIC-XT-PIC i8042
14: 0 0 XT-PIC-XT-PIC pata_amd
15: 0 0 XT-PIC-XT-PIC pata_amd
NMI: 81 78 Non-maskable interrupts
LOC: 2386834 1935552 Local timer interrupts
SPU: 0 0 Spurious interrupts
PMI: 81 78 Performance monitoring interrupts
IWI: 0 0 IRQ work interrupts
RES: 1343954 5673656 Rescheduling interrupts
CAL: 10113 12523 Function call interrupts
TLB: 859 674 TLB shootdowns
TRM: 0 0 Thermal event interrupts
THR: 0 0 Threshold APIC interrupts
MCE: 0 0 Machine check exceptions
MCP: 493 493 Machine check polls
ERR: 6233341
MIS: 0
BTW, the Firewire audio is now working flawlessly, even with very small
buffers/low latency (up to the point I run out of CPU). :)
Thanks again,
Chris
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