Re: [PATCH V9 2/2] powerpc/nodes: Ensure enough nodes avail for operations

Michael Bringmann [off-list ref] writes:

To: linuxppc-dev@lists.ozlabs.org

From: Michael Bringmann <redacted>

To: linux-kernel@vger.kernel.org
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michael Bringmann <redacted>
Cc: John Allen <redacted>
Cc: Nathan Fontenot <redacted>
Subject: [PATCH V9 2/2] powerpc/nodes: Ensure enough nodes avail for operations

powerpc/nodes: On systems like PowerPC which allow 'hot-add' of CPU
or memory resources, it may occur that the new resources are to be
inserted into nodes that were not used for these resources at bootup.
In the kernel, any node that is used must be defined and initialized
at boot.

This patch extracts the value of the lowest domain level (number of
allocable resources) from the "rtas" device tree property
"ibm,max-associativity-domains" to use as the maximum number of nodes
to setup as possibly available in the system.  This new setting will
override the instruction,

Thanks for implementing my suggestion of using "ibm,max-associativity-domains".

However I don't think it's correct to use the lowest domain level.

It's not very clearly specified in PAPR, but I think you need to treat
it like an associativity property and index into based on the
associativity reference points.

You should be able to use min_common_depth as the index.

cheers