Re: [PATCH 1/4] kernel: local_irq_{save,restore}_nmi()

From: Paul Mundt
Date: Fri Jun 04 2010 - 01:04:19 EST


On Fri, Apr 09, 2010 at 04:01:35PM -0700, David Miller wrote:
>
> Provide local_irq_{save,restore}_nmi() which will allow us to help
> architectures that implement NMIs using IRQ priorities like SPARC64
> does.
>
> Sparc uses IRQ prio 15 for NMIs and implements local_irq_disable() as
> disable <= 14. However if you do that while inside an NMI you re-
> enable the NMI priority again, causing all kinds of fun.
>
> A more solid implementation would first check the disable level and
> never lower it, however that is more costly and would slow down the
> rest of the kernel for no particular reason.
>
> Therefore introduce local_irq_save_nmi() which can implement this
> slower but more solid scheme and dis-allow local_irq_save() from NMI
> context.
>
> Suggested-by: David Miller <davem@xxxxxxxxxxxxx>
> Signed-off-by: Peter Zijlstra <a.p.zijlstra@xxxxxxxxx>
> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>

Are there any updates for this patch series? I would like to make use of
this on SH as well, but it seems these haven't hit upstream yet.
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