Re: [PATCH 4/7] perf: Check if HT is supported and enabled

From: H. Peter Anvin
Date: Tue Jan 04 2011 - 14:02:11 EST


On 01/04/2011 05:58 AM, Peter Zijlstra wrote:
> On Tue, 2011-01-04 at 14:52 +0100, Stephane Eranian wrote:
>>
>> Couldn't you simply over-provision, and then when the CPU is online, use my
>> ht_enabled statement to figure out whether or not you need to handle the sharing
>> issue?
>
> That's pretty much what Lin's latest does:
>
> X86_FEATURE_HT && smp_num_siblings > 1
>
> shows the CPU is capable of HT and will allocate the needed resources.
>

>From the sound of it, it doesn't seem like it's worth optimizing out the
fairly small memory allocation.

-hpa

--
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/