Re: Interrupt latency problems

Dan Nelson wrote:
> In the last episode (May 19), Lars Eggert said:
> 
>>Paul Richards wrote:
>>
>>>I'm also not sure why a lot more people aren't seeing this, unless
>>>my motherboard is odd in sharing the acpi interrupt with a pci
>>>slot.
>>
>>I tried to see if this is the case on my SMP board, but I don't seem
>>to have acpi attached to any interrupt:
>>
>>[root_at_nik: ~] ps -axg | grep irq
>>   24  ??  WL     0:00.00  (irq18: mpt0)
>>   25  ??  WL     0:19.30  (irq19: em0 mpt1)
>>   26  ??  WL     0:00.00  (irq16: xl0 uhci1)
>>   27  ??  WL     1:57.07  (irq17: fwohci0 drm0)
>>   28  ??  WL     1:09.27  (irq13: em1 ichsmb0)
>>   29  ??  WL     0:00.02  (irq20: pcm0)
>>   30  ??  WL     0:02.19  (irq2: uhci0 bktr0)
>>   31  ??  WL     0:02.84  (irq14: ata0)
>>   32  ??  WL     0:00.00  (irq15: ata1)
>>   36  ??  WL     0:00.00  (irq6: fdc0)
>>   37  ??  WL     0:00.00  (irq1: atkbd0)
>>
>>Is this the right way to check for this?
> 
> 
> You sure you have acpi loaded?  It shows up for me:
> 
> $ ps ax | grep acpi0
>    22  ??  WL     0:00.00  (irq9: acpi0)

I'm pretty sure I do - maybe acpi irq handling is different with an SMP 
kernel?

[larse_at_nik: ~] ps ax | grep acpi
     5  ??  IL     0:00.00  (acpi_task0)
     6  ??  IL     0:00.00  (acpi_task1)
     7  ??  IL     0:00.00  (acpi_task2)
78714  p4  LV+    0:00.00 grep acpi (tcsh)

[larse_at_nik: ~] kldstat | grep acpi
46    1 0xc068b000 48514    acpi.ko

[larse_at_nik: ~] grep -i acpi /var/run/dmesg.boot
Preloaded elf module "/boot/kernel/acpi.ko" at 0xc06d6fa8.
Features=0x3febfbff<FPU,VME,DE,PSE,TSC,MSR,PAE,MCE,CX8,APIC,SEP,MTRR,PGE,MCA,CMOV,PAT,PSE36,CLFLUSH,DTS,ACPI,MMX,FXSR,SSE,SSE2,SS,HTT,TM>
acpi0: <DELL   WS 530 > on motherboard
acpi0: power button is handled as a fixed feature programming model.
Timecounter "ACPI-fast"  frequency 3579545 Hz
acpi_timer0: <24-bit timer at 3.579545MHz> port 0x808-0x80b on acpi0
acpi_cpu0: <CPU> on acpi0
acpi_cpu1: <CPU> on acpi0
acpi_cpu2: <CPU> on acpi0
acpi_cpu3: <CPU> on acpi0
<...>

> Maybe the attach message to acpi should print the IRQ it's using.  All
> I get in dmesg is "acpi0: <ASUS   CUV4X-D > on motherboard".

Lars
-- 
Lars Eggert <larse_at_isi.edu>           USC Information Sciences Institute