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Date: Tue, 12 Nov 2013 19:08:44 +0100
From: Peter Zijlstra <peterz@infradead.org>
To: Dietmar Eggemann <dietmar.eggemann@arm.com>
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Subject: Re: [RFC][PATCH v5 01/14] sched: add a new arch_sd_local_flags for
 sched_domain init
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On Tue, Nov 12, 2013 at 05:43:36PM +0000, Dietmar Eggemann wrote:
> This patch removes the sched_domain initializer macros
> SD_[SIBLING|MC|BOOK|CPU]_INIT in core.c and in archs and replaces them
> with calls to the new function sd_init().  The function sd_init
> incorporates the already existing function sd_numa_init().

Your patch retains far too much of the weird behavioural variations we
have, nor does it create a proper separation between topology and
behaviour.

We might indeed have to have a single arch_() function that adds
SD_flags, but please restrict the flags it can set -- never allow it to
set behavioural flags.

Furthermore, I think we want to allow the arch to override the base
topology; we've had desire to add per arch level in the past.. eg. add
an L2 level for some x86 variants.