Re: [PATCH v12 4/5] arm64, numa: Add NUMA support for arm64 platforms.

[Robert Richter]

On 22.02.16 17:58:22, David Daney wrote:
> From: Ganapatrao Kulkarni <gkulkarni@xxxxxxxxxxxxxxxxxx>
> 
> Attempt to get the memory and CPU NUMA node via of_numa.  If that
> fails, default the dummy NUMA node and map all memory and CPUs to node
> 0.
> 
> Tested-by: Shannon Zhao <shannon.zhao@xxxxxxxxxx>
> Reviewed-by: Robert Richter <rrichter@xxxxxxxxxx>
> Signed-off-by: Ganapatrao Kulkarni <gkulkarni@xxxxxxxxxxxxxxxxxx>
> Signed-off-by: David Daney <david.daney@xxxxxxxxxx>
> ---
>  arch/arm64/Kconfig                |  26 +++
>  arch/arm64/include/asm/mmzone.h   |  12 ++
>  arch/arm64/include/asm/numa.h     |  45 +++++
>  arch/arm64/include/asm/topology.h |  10 +
>  arch/arm64/kernel/pci.c           |  10 +
>  arch/arm64/kernel/setup.c         |   4 +
>  arch/arm64/kernel/smp.c           |   4 +
>  arch/arm64/mm/Makefile            |   1 +
>  arch/arm64/mm/init.c              |  34 +++-
>  arch/arm64/mm/mmu.c               |   1 +
>  arch/arm64/mm/numa.c              | 403 ++++++++++++++++++++++++++++++++++++++
>  11 files changed, 545 insertions(+), 5 deletions(-)
>  create mode 100644 arch/arm64/include/asm/mmzone.h
>  create mode 100644 arch/arm64/include/asm/numa.h
>  create mode 100644 arch/arm64/mm/numa.c

> +static int __init numa_init(int (*init_func)(void))
> +{
> +	int ret;
> +
> +	nodes_clear(numa_nodes_parsed);
> +	nodes_clear(node_possible_map);
> +	nodes_clear(node_online_map);
> +	numa_free_distance();
> +
> +	ret = numa_alloc_distance();
> +	if (ret < 0)
> +		return ret;

If you move this before the remaining initializers, you will need to
clean this up on error. So better move it back after
numa_register_nodes() as it was in v10. This should work since
distances are used not earlier than numa is enabled.

-Robert

> +
> +	ret = init_func();
> +	if (ret < 0)
> +		return ret;
> +
> +	if (nodes_empty(numa_nodes_parsed))
> +		return -EINVAL;
> +
> +	ret = numa_register_nodes();
> +	if (ret < 0)
> +		return ret;
> +
> +	setup_node_to_cpumask_map();
> +
> +	/* init boot processor */
> +	cpu_to_node_map[0] = 0;
> +	map_cpu_to_node(0, 0);
> +
> +	return 0;
> +}