Re: [PATCH v2] ARM: smp: Only expose /sys/.../cpuX/online if hotpluggable

From: Magnus Damm
Date: Sat Feb 14 2015 - 05:01:33 EST


Hi Russell,

On Fri, Feb 13, 2015 at 11:01 PM, Russell King - ARM Linux
<linux@xxxxxxxxxxxxxxxx> wrote:
> On Fri, Feb 13, 2015 at 09:44:50PM +0000, Magnus Damm wrote:
>> Also, based on the comment in mcpm_cpu_can_disable() it looks like the
>> PSCI hook may be executed once only with your change in place?
>> Hopefully PSCI is OK not being invoked for every CPU shutdown.
>
> This is why I've said (in the parent thread) that I'm not happy to
> apply this patch. Mark Rutland has indicated that he has MCPM cases
> where the CPUs which can be disabled changes dynamically according
> to the secure firmware requirements, and ripping out todays
> infrastructure in light of that, only to have to add it back again
> later makes no sense.
>
> However, cleaning things up by removing unnecessary cpu_disable
> methods is a good thing to do irrespective of that.

I completely agree!

Cheers,

/ magnus
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