Re: IRQ splitting

From: Robert Hancock
Date: Thu Apr 05 2007 - 10:35:31 EST


Jan Engelhardt wrote:
Hello list,



let's take the following /proc/interrupts dump (CPU2,CPU3 trimmed)...

CPU0 CPU1
0: 37041766 37038991 IO-APIC-edge timer
1: 10 2 IO-APIC-edge i8042
8: 0 0 IO-APIC-edge rtc
9: 0 0 IO-APIC-level acpi
12: 114 0 IO-APIC-edge i8042
14: 25219 5800049 IO-APIC-edge ide0
201: 260381 238454 IO-APIC-level aacraid
209: 0 0 IO-APIC-level ohci_hcd:usb1
217: 0 0 IO-APIC-level ehci_hcd:usb2
225: 57531742 0 IO-APIC-level eth0,radeon@pci:0000:03:00.0
233: 26 0 IO-APIC-level eth1
NMI: 1661 1397
LOC: 147579966 147579949
ERR: 0
MIS: 0

My question is whether it is possible that eth0's interrupts go to CPU0
and radeon's to CPU1, and if so, how I would enable that. Alternatively,
is it possible to just move eth0 or radeon to a different interrupt?

Generally (at least in APIC mode) the IRQ assignments are based on hard-wired interrupt lines on the board. In this case, the slots that the Radeon and eth0 card are in likely share a physical interrupt line and there is no way to separate them in software. You can try moving the card(s) to different slots..

--
Robert Hancock Saskatoon, SK, Canada
To email, remove "nospam" from hancockr@xxxxxxxxxxxxx
Home Page: http://www.roberthancock.com/

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