2009-06-03 04:55:20

by Geunsik Lim

[permalink] [raw]
Subject: Re: 2.6.29.4-rt16

On Mon, May 25, 2009 at 10:47 PM, Thomas Gleixner <[email protected]> wrote:
>
>    http://www.kernel.org/pub/linux/kernel/v2.6/linux-2.6.29.4.tar.bz2
>    http://www.kernel.org/pub/linux/kernel/projects/rt/patch-2.6.29.4-rt16.bz2

Thank you for notice of 2.6.29.r-rt16 release.

This is a report about "/proc/interrupts" result in my development system.

* System requirements :
Core2 Quad Q6600 , LV-676 Motherboard , SATA 160G, DDR2 3G ,
ftp://ftp.commell.com.tw/COMMELL/support/LV-676/BIOS/676x161.zip.

In summary, I can't get irq loadbalancing(/proc/interrupts) in my system using
2.6.29.4-rt16 linux kernel because of LV-676 motherboard's H/W problem.
( I disabled [ ]irqbalance - userspace with "ntsysv" command in this
experiment . )


[[email protected] ~]$
[[email protected] ~]$
[[email protected] ~]$ cat /proc/interrupts
CPU0 CPU1 CPU2 CPU3
0: 136 0 0 0 IO-APIC-edge timer
1: 2 0 0 0 IO-APIC-edge i8042
3: 2 0 0 0 IO-APIC-edge
4: 2 0 0 0 IO-APIC-edge
6: 2 0 0 0 IO-APIC-edge floppy
7: 0 0 0 0 IO-APIC-edge lpptest
8: 1 0 0 0 IO-APIC-edge rtc
9: 1 0 0 0 IO-APIC-fasteoi acpi
16: 0 0 0 0 IO-APIC-fasteoi
uhci_hcd:usb3
18: 15030 2133 4521 0 IO-APIC-fasteoi
libata, libata, uhci_hcd:usb6
19: 1133 0 0 0 IO-APIC-fasteoi
ehci_hcd:usb1, uhci_hcd:usb7
20: 3 0 0 0 IO-APIC-fasteoi
ehci_hcd:usb2, uhci_hcd:usb5
21: 0 0 0 0 IO-APIC-fasteoi
uhci_hcd:usb4
223: 871 0 0 0 PCI-MSI-edge eth1
NMI: 0 0 0 0 Non-maskable interrupts
LOC: 158448 161871 160140 161074 Local timer interrupts
RES: 735 822 1378 1028 Rescheduling interrupts
CAL: 3397 3408 1948 2452 function call interrupts
TLB: 240 288 266 310 TLB shootdowns
TRM: 0 0 0 0 Thermal event interrupts
SPU: 0 0 0 0 Spurious interrupts
ERR: 0
MIS: 0
[[email protected] ~]$

So, I asked Commell company about this problems.
For reference, Belows is answer from their technical service team.

-- [ From [email protected]] ---------------------------------------------
Hi
Sorry for keep you waiting.
We had setn LV-676 motherboard to BIOS vendor for solution,
still now no resond yet, any respond will pass to you.

We had constantly push for solution, and BIOS vendor is working on this
issue and attempt to solve this problem,
any message from them will let you know.
BR
K.H. Ooi
------------------------------------------------------------------------------------

Currently, I am using "smp_affinity" in this LV-676 mother board like belows.

Binary Hex
CPU 0 0001 1
CPU 1 0010 2
CPU 2 0100 4
CPU 3 1000 8

[[email protected] ~]$
[[email protected] ~]$ echo 8 > /proc/irq/18/smp_affinity
[[email protected] ~]$ for i in `ls -1 /proc/irq/*/smp_affinity`; do
echo "smp affinity CPU3 +++ $i"; echo 8 > $i; done <-- assign irq
to CPU3
[[email protected] ~]$ cat /proc/interrupts <---check irq-balancing

* Don't use irq affinity about timer irq
[[email protected] ~]$ echo 8 > /proc/irq/0/smp_affinity
-bash: echo: write error: Input/output error




--
Regards,
GeunSik Lim ( Samsung Electronics )
Blog : http://blog.naver.com/invain/
e-Mail: [email protected]
[email protected] , [email protected]