Re: [PATCH 13/16] x86: Unify cpu/apicid <-> NUMA node mapping between32 and 64bit

From: Yinghai Lu
Date: Fri Dec 10 2010 - 16:19:21 EST


On 12/10/2010 12:54 PM, Tejun Heo wrote:
> On 12/10/2010 09:45 PM, Tejun Heo wrote:
>> I can change srat_detect_node() and nearby_node() to index by cpu but
>> as I have no idea what kind of broken configurations this is supposed
>> to deal with, I'm concerned that this may lead to different outcome by
>> walking the table in a different order. I can implement an apicid ->
>> numa node mapping function for this but this is something which is
>> inherently ugly, so maybe it's best to leave it ugly.
>
> Oh, right, another problem. It's possible that apicid <-> numa
> mapping exists when apicid <-> cpu doesn't. Again, this is a corner
> case which might not matter but I have no idea what kind of brokeness
> is being worked around and it would also be difficult to test whether
> the change is okay.
>

that could happen...when SRAT and MADT is in different order. and your are booting nr_cpus=<less....> in SRAT...

should be fixed in
https://lkml.org/lkml/2010/11/22/5

Thanks

Yinghai
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/