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Date: Thu, 18 Jan 2007 20:06:05 -0500
From: Livio Soares <livio@eecg.toronto.edu>
To: Benjamin Herrenschmidt <benh@kernel.crashing.org>, linuxppc-dev@ozlabs.org
Subject: Re: [PATCH][PowerPC] Remove ineffective CONFIG_IRQ_ALL_CPUS option
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  Sorry to reply to myself, but...

Livio Soares writes:
>   Hello Ben,
> 
> Benjamin Herrenschmidt writes:
> > On Wed, 2007-01-17 at 18:02 -0500, Livio Soares wrote:
> 
> [...]

>   On  a side  note, I  probably need  to make  IRQ distribution  configurable at
> run-time (for  my personal work).  I  was thinking of exporting  a bit-mask type
> structure  through sysfs,  to enable  run-time configuration  of CPUs  which can
> receive interrupts (and possibly priorities). Would people be interested in such
> a patch?

  Looking at  the code, I found out  that this is _already_  being done; through
setting  affinities  of  interrupts.  If  you  can  get  the  bitmask  right  in
/proc/irq/[IRQ#]/smp_affinity,  you can  change the  distribution  of interrupts
(furthermore,  potentially  disable a  particular  IRQ  altogether a  particular
CPU). 

  Sorry for the noise,

			Livio