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From: Ard Biesheuvel <ardb@kernel.org>
Date: Tue, 21 Sep 2021 14:06:24 +0200
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Subject: Re: [RFC PATCH 0/8] Move task_struct::cpu back into thread_info
To: Mark Rutland <mark.rutland@arm.com>, Michael Ellerman <mpe@ellerman.id.au>,
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On Tue, 14 Sept 2021 at 15:55, Mark Rutland <mark.rutland@arm.com> wrote:
>
> On Tue, Sep 14, 2021 at 02:10:28PM +0200, Ard Biesheuvel wrote:
> > Commit c65eacbe290b ("sched/core: Allow putting thread_info into
> > task_struct") mentions that, along with moving thread_info into
> > task_struct, the cpu field is moved out of the former into the latter,
> > but does not explain why.
>
> From what I recall of talking to Andy around that time, when converting
> arm64 over, the theory was that over time we'd move more and more out of
> thread_info and into task_struct or thread_struct, until task_struct
> supplanted thread_info entirely, and that all became generic.
>
> I think the key gain there was making things more *generic*, and there
> are other ways we could do that in future without moving more into
> task_struct (e.g. with a geenric thread_info and arch_thread_info inside
> that).
>
> With that in mind, and given the diffstat, I think this is worthwhile.
>
> FWIW, for the series:
>
> Acked-by: Mark Rutland <mark.rutland@arm.com>
>

Thanks.

Any comments on this from the various arch maintainers? Especially
power, as Christophe seems happy with this but there are 3 different
patches affecting power that need a maintainer ack.