[libvirt] [PATCH 1/3] nodeinfo: Add check and workaround to guarantee valid cpu topologies

[Viktor Mihajlovski]

On 11/07/2012 04:22 PM, Peter Krempa wrote:
> +    /* Now check if the topology makes sense. There are machines that don't
> +     * expose their real number of nodes or for example the AMD Bulldozer
> +     * architecture that exposes their Clustered integer core modules as both
> +     * threads and cores. This approach throws off our detection. Unfortunately
> +     * the nodeinfo structure isn't designed to carry the full topology so
> +     * we're going to lie about the detected topology to notify the user
> +     * to check the host capabilities for the actual topology. */
> +    if ((nodeinfo->nodes *
> +         nodeinfo->sockets *
> +         nodeinfo->cores *
> +         nodeinfo->threads) != (nodeinfo->cpus + offline)) {
> +        nodeinfo->nodes = 1;
> +        nodeinfo->sockets = nodeinfo->cpus;
To really fix the wrong topology this should be
+        nodeinfo->sockets = nodeinfo->cpus + offline;
> +        nodeinfo->cores = 1;
A matter of taste but I would have chosen cores to contain the number of 
CPUs, but fake is fake ... so that's OK :-).
> +        nodeinfo->threads = 1;
> +    }
> +
>       ret = 0;
>
>   cleanup:
>

-- 

Mit freundlichen Grüßen/Kind Regards
    Viktor Mihajlovski

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