Re: [PATCH 00/14] Cleanup on SMP and its test

[Zhao Liu <zhao1.liu@linux.intel.com>]

Hi Philippe,

> In a previous community call, Zhao asked us how his work will scale
> in the heterogeneous context.
> 
> My first idea is CPUs must belong to a cluster.

Thank you for considering this!

At present, cluster is a arch-specific topology level used by ARM.
So maybe we need call this abstraction as another name not "cluster"?

I guess the cluster you mentioned is the cluster device used in TCG,
right? I also tried to eliminate differences between cluster devices
and the cluster level in CPU topology [1].

My previous proposal introduced a abstract topology device [2]. And all
topology specific levels are derived from the underlying topology
device, including CPU.

I feel like this topology device abstraction seems close to your idea,
am I understanding it correctly? ;-)

> For machines without
> explicit cluster, we could always create the first one. Then -smp
> would become a sugar property of the first cluster. Next -smp could
> also be sugar property of the next cluster.

Could you please explain the above ideas more?

It feels we need to split -smp for each cluster. But I'm not sure if
sugar property means defining smp-like properties for each cluster.

Or is there a command line example? ;-)

[1]: https://lore.kernel.org/qemu-devel/20231130144203.2307629-23-zhao1.liu@linux.intel.com/
[2]: https://lore.kernel.org/qemu-devel/20231130144203.2307629-9-zhao1.liu@linux.intel.com/

Thanks,
Zhao