Re: Interrupts in Xen: Dynamic-irq and Phys-irq

[John Que <qwejohn@gmail.com>]

Hello, 

Thanks!
Your answer makes things more understandable.

Regards,
John 

On 7/18/05, Keir Fraser <Keir.Fraser@cl.cam.ac.uk> wrote:
> 
> On 18 Jul 2005, at 13:07, John Que wrote:
> 
> > The "Dynamic-irq" also appears in Dom0 (for example, when you run
> > "cat /proc/interrupts" and look at the  line containing "ctrl-if" or
> > "console").
> >
> > Besides it, In dom0 there is also "Phys-irq" ; for examples,after
> > running "cat /proc/interruupts" in line containing "eth0" or "ide0" or
> > "ide1".
> >
> > what is the difference between these 2 types of interrupts ?
> 
> Phys-irq's relate directly to hardware IRQ lines (e.g., eth0, your disc
> controller, etc). Dynamic-irq's are perhaps better described as
> 'virtual IRQs'. They have no direct relation to physical IRQ lines, but
> originate from things like timer events in Xen, or from the other half
> of a 'split' virtual block or network driver. We call them 'dynamic
> IRQs' because the IRQ numbers are dynamically allocated. :-)
> 
>   -- Keir
> 
>