Re: [PATCH RFC] x86: fix confusing name of /proc/cpuinfo "ht" flag

From: Alexander Clouter
Date: Thu Nov 12 2009 - 12:08:53 EST


Chris Friesen <cfriesen@xxxxxxxxxx> wrote:
>>
>> "ht" flag indicates only ability to detect siblings not HT presence itself.
>>
>> Inspired by:
>> http://www.codemonkey.org.uk/2009/11/10/common-hyperthreading-misconception/
>>
>> Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@xxxxxxxxx>
>> ---
>> It could be that there are some user-space programs depending on "ht"
>> flag so the patch is marked as RFC..
>
> If a cpu is capable of ht but doesn't have any siblings, do we actually
> care?
>
I have a Core2 Duo U7600 with siblings set to 2 and the 'ht' flag and I
know the CPU in my lapdog does not actually support hyperthreading.

> If many people consider the "ht" flag to indicate that hyperthreading is
> actually available, what about instead changing the meaning of the "ht"
> flag to indicate that there actually are siblings?
>
Could be determined surely by "grep siblings /proc/cpuinfo"?

Cheers

--
Alexander Clouter
.sigmonster says: Old musicians never die, they just decompose.

--
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/