Re: [PATCH v10 2/6] x86: Support Generic Initiator only proximity domains

[Borislav Petkov]

On Mon, Sep 07, 2020 at 10:03:03PM +0800, Jonathan Cameron wrote:
> In common with memoryless domains we 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>
> ---
>  arch/x86/include/asm/numa.h |  2 ++
>  arch/x86/kernel/setup.c     |  1 +
>  arch/x86/mm/numa.c          | 14 ++++++++++++++
>  3 files changed, 17 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();

Can this function be an early_initcall() or so instead which you can
call in numa.c directly instead of exporting it and calling it here?

>  	io_apic_init_mappings();
>  
> diff --git a/arch/x86/mm/numa.c b/arch/x86/mm/numa.c
> index aa76ec2d359b..fc630dc6764e 100644
> --- a/arch/x86/mm/numa.c
> +++ b/arch/x86/mm/numa.c
> @@ -747,6 +747,20 @@ static void __init init_memory_less_node(int nid)
>  	 */
>  }
>  
> +/*
> + * Generic Initiator Nodes may have neither CPU nor Memory.
> + * At this stage if either of the others were present we would

Who's "we"? And what is "either of the others"? The other nodes?

-- 
Regards/Gruss,
    Boris.

https://people.kernel.org/tglx/notes-about-netiquette