Re: [PATCH v2 2/3] powerpc/numa: Allow cpu_to_coregroup_id without PPC_SPLPAR

[Ritesh Harjani (IBM) <ritesh.list@gmail.com>]

Srikar Dronamraju <srikar@linux.ibm.com> writes:

> Make cpu_to_coregroup_id() available outside PPC_SPLPAR so it can be
> used by platforms that do not rely on the SPLPAR-specific VPHN path.
>
> Keep the existing fallback behavior by returning the core ID when
> coregroup information is unavailable.
>

Looks like this mainly brings the cpu_to_coregroup_id() outside of
CONFIG_PPC_SPLPAR gate. 

> Signed-off-by: Srikar Dronamraju <srikar@linux.ibm.com>
> ---
> Changelog from v1:
> - Handle comments from Christophe Leroy; Remove extern key word in
>   declaration
>
>  arch/powerpc/include/asm/topology.h | 15 +++++++--------
>  arch/powerpc/mm/numa.c              | 22 ++++++++++++++++------
>  2 files changed, 23 insertions(+), 14 deletions(-)
>
> diff --git a/arch/powerpc/include/asm/topology.h b/arch/powerpc/include/asm/topology.h
> index 66ed5fe1b718..385715f1ad56 100644
> --- a/arch/powerpc/include/asm/topology.h
> +++ b/arch/powerpc/include/asm/topology.h
> @@ -71,6 +71,7 @@ extern void map_cpu_to_node(int cpu, int node);
>  extern void unmap_cpu_from_node(unsigned long cpu);
>  #endif /* CONFIG_HOTPLUG_CPU */
>  
> +int cpu_to_coregroup_id(int cpu);
>  #else
>  
>  static inline int early_cpu_to_node(int cpu) { return 0; }
> @@ -107,14 +108,6 @@ static inline void map_cpu_to_node(int cpu, int node) {}
>  static inline void unmap_cpu_from_node(unsigned long cpu) {}
>  #endif /* CONFIG_HOTPLUG_CPU */
>  #endif /* CONFIG_SMP */
> -
> -#endif /* CONFIG_NUMA */
> -
> -#if defined(CONFIG_NUMA) && defined(CONFIG_PPC_SPLPAR)
> -void find_and_update_cpu_nid(int cpu);
> -extern int cpu_to_coregroup_id(int cpu);
> -#else
> -static inline void find_and_update_cpu_nid(int cpu) {}
>  static inline int cpu_to_coregroup_id(int cpu)
>  {
>  #ifdef CONFIG_SMP
> @@ -124,6 +117,12 @@ static inline int cpu_to_coregroup_id(int cpu)
>  #endif
>  }
>  
> +#endif /* CONFIG_NUMA */
> +
> +#if defined(CONFIG_NUMA) && defined(CONFIG_PPC_SPLPAR)
> +void find_and_update_cpu_nid(int cpu);
> +#else
> +static inline void find_and_update_cpu_nid(int cpu) {}
>  #endif /* CONFIG_NUMA && CONFIG_PPC_SPLPAR */
>  
>  #include <asm-generic/topology.h>
> diff --git a/arch/powerpc/mm/numa.c b/arch/powerpc/mm/numa.c
> index c44a80d8fc11..9aa71eb7e96b 100644
> --- a/arch/powerpc/mm/numa.c
> +++ b/arch/powerpc/mm/numa.c
> @@ -1428,6 +1428,21 @@ void find_and_update_cpu_nid(int cpu)
>  	pr_debug("%s:%d cpu %d nid %d\n", __func__, __LINE__, cpu, new_nid);
>  }
>  
> +static int topology_update_init(void)
> +{
> +	topology_inited = 1;
> +	return 0;
> +}
> +device_initcall(topology_update_init);
> +
> +#else
> +static long vphn_get_associativity(unsigned long cpu,
> +					__be32 *associativity)
> +{
> +	return -1;
> +}
> +#endif /* CONFIG_PPC_SPLPAR */
> +
>  int cpu_to_coregroup_id(int cpu)
>  {
>  	__be32 associativity[VPHN_ASSOC_BUFSIZE] = {0};
> @@ -1453,10 +1468,5 @@ int cpu_to_coregroup_id(int cpu)
>  	return cpu_to_core_id(cpu);
>  }
>  
> -static int topology_update_init(void)
> -{
> -	topology_inited = 1;
> -	return 0;
> +	return coregroup_id;
>  }

These above two lines seems to be out of any function scope. So applying
only patch-1 & patch-2 will give a compile error. This needs fixing.

-ritesh

> -device_initcall(topology_update_init);
> -#endif /* CONFIG_PPC_SPLPAR */
> -- 
> 2.43.0