[RFC PATCH v3 4/4] arm64:numa: adding numa support for arm64 platforms.

[Ganapatrao Kulkarni]

On Wed, Jan 7, 2015 at 1:29 AM, Arnd Bergmann <arnd at arndb.de> wrote:
> On Tuesday 06 January 2015 14:55:53 Ganapatrao Kulkarni wrote:
>> On Sat, Jan 3, 2015 at 2:40 AM, Arnd Bergmann <arnd at arndb.de> wrote:
>> >> +int dt_get_cpu_node_id(int cpu)
>> >> +{
>> >> +     struct device_node *dn = NULL;
>> >> +
>> >> +     while ((dn = of_find_node_by_type(dn, "cpu"))) {
>> >> +             const u32 *cell;
>> >> +             u64 hwid;
>> >> +
>> >> +             /*
>> >> +              * A cpu node with missing "reg" property is
>> >> +              * considered invalid to build a cpu_logical_map
>> >> +              * entry.
>> >> +              */
>> >> +             cell = of_get_property(dn, "reg", NULL);
>> >> +             if (!cell) {
>> >> +                     pr_err("%s: missing reg property\n", dn->full_name);
>> >> +                     return default_nid;
>> >> +             }
>> >> +             hwid = of_read_number(cell, of_n_addr_cells(dn));
>> >> +
>> >> +             if (cpu_logical_map(cpu) == hwid)
>> >> +             return of_node_to_nid_single(dn);
>> >> +     }
>> >> +     return NUMA_NO_NODE;
>> >> +}
>> >> +EXPORT_SYMBOL(dt_get_cpu_node_id);
>> >
>> > Maybe just expose a function to the device node for a CPU ID here, and
>> > expect callers to use of_node_to_nid?
>> shall i make this wrapper function in dt_numa.c, which will use
>> functions _of_node_to_nid and  _of_cpu_to_node(cpu)
>
> Yes, I guess that would work.
>
>> And,  this function can be a weak function in numa.c which returns 0.
>
> No, please don't use weak functions. You can either use IS_ENABLED()
> tricks to remove function calls at compile-time, or in the header
> file provide an inline function as an alternative to the extern
> declaration, based on a configuration symbol.
ok
>
>         Arnd
thanks
ganaapat