Re: [Xen-devel] hardware interrupt

[Daniel Stodden <stodden@xxxxxxxxxx>]

On Tue, 2007-10-23 at 15:57 -0700, Agarwal, Lomesh wrote:
> Is there a way I can find out on which physical processor I am receiving
> interrupt from a particular device? 

if you know the irq number.

the path taken on irqs is roughly IRQ0x**_interrupt -> common_interrupt
-> do_IRQ() (C, finally), then back to guest context via ret_from_intr.
see the definition of BUILD_COMMON_INTERRUPT() and related.

if it's bound, it will visit send_guest_pirq().

as far as i know, the physical cpu does not leak to guest context, so
it's going to be the VMM.

you get the physical cpu number via smp_processor_id().

> Can I put prints somewhere in Xen to
> do that?

printk in irq context isn't exactly scalable, but you'll might just get
away with it.

hth,
daniel

-- 
Daniel Stodden
LRR     -      Lehrstuhl fÃr Rechnertechnik und Rechnerorganisation
Institut fÃr Informatik der TU MÃnchen             D-85748 Garching
http://www.lrr.in.tum.de/~stodden         mailto:stodden@xxxxxxxxxx
PGP Fingerprint: F5A4 1575 4C56 E26A 0B33  3D80 457E 82AE B0D8 735B



_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel