On Fri, Nov 20, 2015 at 06:24:30PM +0530, Bharata B Rao wrote: > Prevent guests from booting with CPU topologies that have partially > filled CPU cores or can result in partially filled CPU cores after > CPU hotplug like > > -smp 15,sockets=1,cores=4,threads=4,maxcpus=16 or > -smp 15,sockets=1,cores=4,threads=4,maxcpus=17. > > Signed-off-by: Bharata B Rao <bhar...@linux.vnet.ibm.com>
Reviewed-by: David Gibson <da...@gibson.dropbear.id.au>
I may have missed a bit of the discussion leading up to this. What
was the rationale for still allowing partially filled sockets (and
otherwise doing things at core rather than socket level?)
> ---
> vl.c | 9 +++++++++
> 1 file changed, 9 insertions(+)
>
> diff --git a/vl.c b/vl.c
> index 7d993a5..23a1a1e 100644
> --- a/vl.c
> +++ b/vl.c
> @@ -1248,6 +1248,15 @@ static void smp_parse(QemuOpts *opts)
> exit(1);
> }
>
> + if (cpus % threads || max_cpus % threads) {
> + error_report("cpu topology: "
> + "sockets (%u) cores (%u) threads (%u) with "
> + "smp_cpus (%u) maxcpus (%u) "
> + "will result in partially filled cores",
> + sockets, cores, threads, cpus, max_cpus);
> + exit(1);
> + }
> +
> smp_cpus = cpus;
> smp_cores = cores > 0 ? cores : 1;
> smp_threads = threads > 0 ? threads : 1;
--
David Gibson | I'll have my music baroque, and my code
david AT gibson.dropbear.id.au | minimalist, thank you. NOT _the_ _other_
| _way_ _around_!
http://www.ozlabs.org/~dgibson
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