Re: sh migor_defconfig build breakage

From: Mike Travis
Date: Thu May 08 2008 - 21:21:33 EST


Paul Mundt wrote:
> On Thu, May 08, 2008 at 03:12:46PM -0700, Mike Travis wrote:
>> Mike Travis wrote:
>>> Because some arch's have it defined as an inline function. Perhaps the
>>> easiest would be to add to include/asm-sh/topology.h a simple define of
>>> cpu_to_node()?
>> Ahh, this is what caused the error. In include/asm-generic/topology.h
>> cpu_to_node is only defined now if NUMA is turned off.
>>
>> #ifndef CONFIG_NUMA
>>
>> /* Other architectures wishing to use this simple topology API should fill
>> in the below functions as appropriate in their own <asm/topology.h> file. */
>> #ifndef cpu_to_node
>> #define cpu_to_node(cpu) ((void)(cpu),0)
>> #endif
>> ...
>>
>> So before my change arch 'sh' used the default define whether NUMA was
>> set or not.
>>
> The dependency here is a bit vague in the first place. For UP NUMA the
> asm-generic definitions are perfectly fine, it's only the CONFIG_NUMA &&
> CONFIG_SMP cases where there is any point in doing anything more
> fine-grained. So while it would be trivial to add a CONFIG_SMP test here
> too, that's likely to break all of the other NUMA platforms.
>
> So while sh can use the asm-generic definitions in the UP case, it
> obviously can't on SMP. The easiest option for now is to just stub the
> asm-generic bits in to asm-sh/topology.h under a CONFIG_NUMA ifdef and
> then add more reasonable definitions for the SMP cases.

The "suggested" patch I submitted sort of covered all the cases of CONFIG_NUMA=y
without regards to CONFIG_SMP. It seems you're suggesting that I only change
the asm-sh/topology.h file and leave the remaining arch's for "error discovery"
later?

Thanks,
Mike

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