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Message-ID: <1486600803.3401.9.camel@kernel.crashing.org>
Subject: Re: [PATCH] powerpc/irq: Improve/fix migrate_irqs()
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Michael Ellerman <mpe@ellerman.id.au>, linuxppc-dev@ozlabs.org
Date: Thu, 09 Feb 2017 11:40:03 +1100
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On Wed, 2017-02-08 at 21:02 +1100, Michael Ellerman wrote:
> Benjamin Herrenschmidt <benh@kernel.crashing.org> writes:
> 
> > migrate_irqs() is used by some platforms to migrate interrupts
> > away from a CPU about to be offlined.
> > 
> > The current implementation had various issues such as not taking
> > the descriptor lock before manipulating it.
> 
> ... and not checking for a NULL chip (but presumably that's never
> happened), and always calling irq_set_affinity() even for IRQs not on
> the CPU.
> 
> But, any reason we can't use irq_migrate_all_off_this_cpu() ?
> Which is in generic code.

Nope, I didn't notice it. I'll give that a spin.

Cheers,
Ben.