Re: [v10, 1/3] powerpc: Detect the presence of big-cores via "ibm, thread-groups"

From: Michael Ellerman
Date: Mon Oct 15 2018 - 00:01:24 EST


On Thu, 2018-10-11 at 05:33:01 UTC, "Gautham R. Shenoy" wrote:
> From: "Gautham R. Shenoy" <ego@xxxxxxxxxxxxxxxxxx>
>
> On IBM POWER9, the device tree exposes a property array identifed by
> "ibm,thread-groups" which will indicate which groups of threads share
> a particular set of resources.
>
> As of today we only have one form of grouping identifying the group of
> threads in the core that share the L1 cache, translation cache and
> instruction data flow.
>
> This patch adds helper functions to parse the contents of
> "ibm,thread-groups" and populate a per-cpu variable to cache
> information about siblings of each CPU that share the L1, traslation
> cache and instruction data-flow.
>
> It also defines a new global variable named "has_big_cores" which
> indicates if the cores on this configuration have multiple groups of
> threads that share L1 cache.
>
> For each online CPU, it maintains a cpu_smallcore_mask, which
> indicates the online siblings which share the L1-cache with it.
>
> Signed-off-by: Gautham R. Shenoy <ego@xxxxxxxxxxxxxxxxxx>

Series applied to powerpc next, thanks.

https://git.kernel.org/powerpc/c/425752c63b6f3fed7b5a9cba2b8101

cheers