Re: [RFC/RFT PATCH v2 2/5] arm64, numa: Change the numa init function name to be generic

[Jonathan Cameron <Jonathan.Cameron@Huawei.com>]

On Fri, 11 Sep 2020 18:34:38 -0700
Atish Patra <atish.patra@wdc.com> wrote:

> As we are using generic numa implementation code, modify the init function
> name to indicate that generic implementation.
> 
> Signed-off-by: Atish Patra <atish.patra@wdc.com>

A few comments inline but more about which layer we do the build protections
at than anything important.

Thanks,

Jonathan

> ---
>  arch/arm64/kernel/acpi_numa.c | 13 -------------
>  arch/arm64/mm/init.c          |  4 ++--
>  drivers/base/arch_numa.c      | 29 ++++++++++++++++++++++++++---
>  include/asm-generic/numa.h    |  4 ++--
>  4 files changed, 30 insertions(+), 20 deletions(-)
> 
> diff --git a/arch/arm64/kernel/acpi_numa.c b/arch/arm64/kernel/acpi_numa.c
> index 7ff800045434..96502ff92af5 100644
> --- a/arch/arm64/kernel/acpi_numa.c
> +++ b/arch/arm64/kernel/acpi_numa.c
> @@ -117,16 +117,3 @@ void __init acpi_numa_gicc_affinity_init(struct acpi_srat_gicc_affinity *pa)
>  
>  	node_set(node, numa_nodes_parsed);
>  }
> -
> -int __init arm64_acpi_numa_init(void)
> -{
> -	int ret;
> -
> -	ret = acpi_numa_init();
> -	if (ret) {
> -		pr_info("Failed to initialise from firmware\n");
> -		return ret;
> -	}
> -
> -	return srat_disabled() ? -EINVAL : 0;
> -}
> diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c
> index 481d22c32a2e..93b660229e1d 100644
> --- a/arch/arm64/mm/init.c
> +++ b/arch/arm64/mm/init.c
> @@ -418,10 +418,10 @@ void __init bootmem_init(void)
>  	max_pfn = max_low_pfn = max;
>  	min_low_pfn = min;
>  
> -	arm64_numa_init();
> +	arch_numa_init();
>  
>  	/*
> -	 * must be done after arm64_numa_init() which calls numa_init() to
> +	 * must be done after arch_numa_init() which calls numa_init() to
>  	 * initialize node_online_map that gets used in hugetlb_cma_reserve()
>  	 * while allocating required CMA size across online nodes.
>  	 */
> diff --git a/drivers/base/arch_numa.c b/drivers/base/arch_numa.c
> index 73f8b49d485c..a4039dcabd3e 100644
> --- a/drivers/base/arch_numa.c
> +++ b/drivers/base/arch_numa.c
> @@ -13,7 +13,9 @@
>  #include <linux/module.h>
>  #include <linux/of.h>
>  
> +#ifdef CONFIG_ACPI_NUMA
>  #include <asm/acpi.h>
> +#endif

Could include linux/acpi.h which I think gets you everything you need in here
and has protections against building for non ACPI cases.

>  #include <asm/sections.h>
>  
>  struct pglist_data *node_data[MAX_NUMNODES] __read_mostly;
> @@ -444,16 +446,37 @@ static int __init dummy_numa_init(void)
>  	return 0;
>  }
>  
> +#ifdef CONFIG_ACPI_NUMA
> +int __init arch_acpi_numa_init(void)
> +{
> +	int ret;
> +
> +	ret = acpi_numa_init();

I wonder if this is the correct level at which to stub this out
as opposed to providing a stub for acpi_numa_init()
and srat_disabled()

At this stage I'm not sure I care too strongly though.

> +	if (ret) {
> +		pr_info("Failed to initialise from firmware\n");
> +		return ret;
> +	}
> +
> +	return srat_disabled() ? -EINVAL : 0;
> +}
> +#else
> +int __init arch_acpi_numa_init(void)
> +{
> +	return -EOPNOTSUPP;
> +}
> +
> +#endif
> +
>  /**
> - * arm64_numa_init() - Initialize NUMA
> + * arch_numa_init() - Initialize NUMA
>   *
>   * Try each configured NUMA initialization method until one succeeds. The
>   * last fallback is dummy single node config encomapssing whole memory.
>   */
> -void __init arm64_numa_init(void)
> +void __init arch_numa_init(void)
>  {
>  	if (!numa_off) {
> -		if (!acpi_disabled && !numa_init(arm64_acpi_numa_init))
> +		if (!acpi_disabled && !numa_init(arch_acpi_numa_init))
>  			return;
>  		if (acpi_disabled && !numa_init(of_numa_init))
>  			return;
> diff --git a/include/asm-generic/numa.h b/include/asm-generic/numa.h
> index 2718d5a6ff03..e7962db4ba44 100644
> --- a/include/asm-generic/numa.h
> +++ b/include/asm-generic/numa.h
> @@ -27,7 +27,7 @@ static inline const struct cpumask *cpumask_of_node(int node)
>  }
>  #endif
>  
> -void __init arm64_numa_init(void);
> +void __init arch_numa_init(void);
>  int __init numa_add_memblk(int nodeid, u64 start, u64 end);
>  void __init numa_set_distance(int from, int to, int distance);
>  void __init numa_free_distance(void);
> @@ -41,7 +41,7 @@ void numa_remove_cpu(unsigned int cpu);
>  static inline void numa_store_cpu_info(unsigned int cpu) { }
>  static inline void numa_add_cpu(unsigned int cpu) { }
>  static inline void numa_remove_cpu(unsigned int cpu) { }
> -static inline void arm64_numa_init(void) { }
> +static inline void arch_numa_init(void) { }
>  static inline void early_map_cpu_to_node(unsigned int cpu, int nid) { }
>  
>  #endif	/* CONFIG_NUMA */