Re: [PATCH 3/3] x86/numa_emulation: restructures numa_nodes_parsed from emulated nodes

From: David Rientjes
Date: Mon Apr 10 2017 - 20:36:34 EST


On Tue, 11 Apr 2017, Wei Yang wrote:

> By emulating numa, it may contains more or less nodes than physical nodes.
> In numa_emulation(), numa_meminfo/numa_distance/__apicid_to_node is
> restructured according to emulated nodes, except numa_nodes_parsed.
>
> This patch restructures numa_nodes_parsed from emulated nodes.
>
> Signed-off-by: Wei Yang <richard.weiyang@xxxxxxxxx>

Acked-by: David Rientjes <rientjes@xxxxxxxxxx>

although there's a small nit: NODE_MASK_NONE is only used for
initialization, this should be nodes_clear(numa_nodes_parsed) instead, but
that would be up to the x86 maintainers to allow it.

> ---
> arch/x86/mm/numa_emulation.c | 7 +++++++
> 1 file changed, 7 insertions(+)
>
> diff --git a/arch/x86/mm/numa_emulation.c b/arch/x86/mm/numa_emulation.c
> index a6d01931b9a1..14f075fc4cc5 100644
> --- a/arch/x86/mm/numa_emulation.c
> +++ b/arch/x86/mm/numa_emulation.c
> @@ -391,6 +391,13 @@ void __init numa_emulation(struct numa_meminfo *numa_meminfo, int numa_dist_cnt)
> /* commit */
> *numa_meminfo = ei;
>
> + /* Make sure numa_nodes_parsed only contains emulated nodes */
> + numa_nodes_parsed = NODE_MASK_NONE;
> + for (i = 0; i < ARRAY_SIZE(ei.blk); i++)
> + if (ei.blk[i].start != ei.blk[i].end &&
> + ei.blk[i].nid != NUMA_NO_NODE)
> + node_set(ei.blk[i].nid, numa_nodes_parsed);
> +
> /*
> * Transform __apicid_to_node table to use emulated nids by
> * reverse-mapping phys_nid. The maps should always exist but fall