Re: [patch 3/5] MIPS: Octeon: Simplify irq_cpu_on/offline irq chip functions

[David Daney <david.s.daney@gmail.com>]

On 03/27/2011 02:29 PM, Thomas Gleixner wrote:
> On Sun, 27 Mar 2011, David Daney wrote:
>
> > On 03/27/2011 09:22 AM, Thomas Gleixner wrote:
> > > Make use of the IRQCHIP_ONOFFLINE_ENABLED flag and remove the
> > > wrappers. Use irqd_irq_disabled() instead of desc->status, which will
> > > go away.
> > I rewrote my patch set and was testing it.  Interesting that I came up with a
> > function with almost the same name and purpose.
> >
> > However my function told us if the irq was masked *or* disabled.  The idea
> > being a function that returns true if the irq could fire.  We cannot be
> > enabling the interrupt in the controller if it is masked.
> >
> > For example I need to test this when adjusting affinity, and taking CPUs on
> > and off line.
> >
> > I don't think your genirq changes can tell the me information I really need in
> > their current state.  I think we need to consider how the masked state
> > interacts with IRQCHIP_ONOFFLINE_ENABLED and irqd_irq_disabled().
> >
> > Since I have totally rewritten my interrupt code, I am a bit ambivalent about
> > applying these patches.  It might make more sense that I adjust my patch for
> > your genirq changes and test it before committing it.
> The modifications I made are 100% equivalent to the code you provided
> in the first place.
Acknowledged.

However subsequently, I made mostly equivalent changes.  The main 
difference is that I added IRQS_MASKED into the mix testing it in 
addition to IRQS_DISABLED
> The IRQCHIP_ONOFFLINE_ENABLED flag is only used for the on/offline
> callbacks. The disabled checked based on irq_data is in the affinity
> setting code.
>
> Unless I'm missing something we should be all set.
As I mentioned in the other e-mail, I am concerned that some of the chip 
functions may get called when the desc is in a IRQS_MASKED istate.
If we can prevent calling .irq_cpu_online when IRQS_MASKED is set that 
might be good.
Perhaps adding a flag similar to IRQCHIP_ONOFFLINE_ENABLED, to disable 
calling .irq_set_affinity when the irq shouldn't be enabled.
With something like that, I think we can get rid of all the checks in 
the irq_chip functions.
Thanks,
David Daney