Re: [PATCH v12 2/6] x86: Support Generic Initiator only proximity domains

[Borislav Petkov]

On Wed, Sep 30, 2020 at 10:05:43PM +0800, Jonathan Cameron wrote:
> In common with memoryless domains only register GI domains
> if the proximity node is not online. If a domain is already
> a memory containing domain, or a memoryless domain there is
> nothing to do just because it also contains a Generic Initiator.
> 
> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx>
> ---
> v12: Update comment to adopt passive voice.
> 
>  arch/x86/include/asm/numa.h |  2 ++
>  arch/x86/kernel/setup.c     |  1 +
>  arch/x86/mm/numa.c          | 21 +++++++++++++++++++++
>  3 files changed, 24 insertions(+)
> 
> diff --git a/arch/x86/include/asm/numa.h b/arch/x86/include/asm/numa.h
> index bbfde3d2662f..f631467272a3 100644
> --- a/arch/x86/include/asm/numa.h
> +++ b/arch/x86/include/asm/numa.h
> @@ -62,12 +62,14 @@ extern void numa_clear_node(int cpu);
>  extern void __init init_cpu_to_node(void);
>  extern void numa_add_cpu(int cpu);
>  extern void numa_remove_cpu(int cpu);
> +extern void init_gi_nodes(void);
>  #else	/* CONFIG_NUMA */
>  static inline void numa_set_node(int cpu, int node)	{ }
>  static inline void numa_clear_node(int cpu)		{ }
>  static inline void init_cpu_to_node(void)		{ }
>  static inline void numa_add_cpu(int cpu)		{ }
>  static inline void numa_remove_cpu(int cpu)		{ }
> +static inline void init_gi_nodes(void)			{ }
>  #endif	/* CONFIG_NUMA */
>  
>  #ifdef CONFIG_DEBUG_PER_CPU_MAPS
> diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
> index 3511736fbc74..9062c146f03a 100644
> --- a/arch/x86/kernel/setup.c
> +++ b/arch/x86/kernel/setup.c
> @@ -1218,6 +1218,7 @@ void __init setup_arch(char **cmdline_p)
>  	prefill_possible_map();
>  
>  	init_cpu_to_node();
> +	init_gi_nodes();
>  
>  	io_apic_init_mappings();
>  
> diff --git a/arch/x86/mm/numa.c b/arch/x86/mm/numa.c
> index aa76ec2d359b..22d3e5ade3ae 100644
> --- a/arch/x86/mm/numa.c
> +++ b/arch/x86/mm/numa.c
> @@ -747,6 +747,27 @@ static void __init init_memory_less_node(int nid)
>  	 */
>  }
>  
> +/*
> + * A node may exist which has one or more Generic Initiators but no CPUs and no
> + * memory.
> + *
> + * This function must be called after init_cpu_to_node(), to ensure that any
> + * memoryless CPU nodes have already been brought online, and before the
> + * node_data[nid] is needed for zone list setup in build_all_zonelists().
> + *
> + * When this function is called, any nodes containing either memory and/or CPUs
> + * will already be online and there is no need to do anything extra, even if
> + * they also contain one or more Generic Initiators.
> + */
> +void __init init_gi_nodes(void)
> +{
> +	int nid;
> +
> +	for_each_node_state(nid, N_GENERIC_INITIATOR)
> +		if (!node_online(nid))
> +			init_memory_less_node(nid);
> +}
> +
>  /*
>   * Setup early cpu_to_node.
>   *
> -- 

Looks perfect, thanks! :-)

Acked-by: Borislav Petkov <bp@xxxxxxx>

-- 
Regards/Gruss,
    Boris.

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