From: "H. Peter Anvin" <hpa@zytor.com>
To: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>,
Lin Ming <ming.m.lin@intel.com>, Ingo Molnar <mingo@elte.hu>,
Andi Kleen <andi@firstfloor.org>,
lkml <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH 4/7] perf: Check if HT is supported and enabled
Date: Tue, 04 Jan 2011 11:00:23 -0800 [thread overview]
Message-ID: <4D236E47.5080500@zytor.com> (raw)
In-Reply-To: <1294149501.2016.141.camel@laptop>
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
next prev parent reply other threads:[~2011-01-04 19:02 UTC|newest]
Thread overview: 15+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-12-27 15:36 [PATCH 4/7] perf: Check if HT is supported and enabled Lin Ming
[not found] ` <AANLkTimp9VgD4qhOVmq-k1Ckzti9eeV8pf6Jvt5YB6nx@mail.gmail.com>
2010-12-28 8:51 ` Lin Ming
2011-01-03 10:58 ` Peter Zijlstra
2011-01-03 15:21 ` Andi Kleen
2011-01-03 19:53 ` H. Peter Anvin
2011-01-04 11:10 ` Peter Zijlstra
2011-01-04 13:38 ` Stephane Eranian
2011-01-04 13:44 ` Peter Zijlstra
2011-01-04 13:52 ` Stephane Eranian
2011-01-04 13:58 ` Peter Zijlstra
2011-01-04 15:35 ` Stephane Eranian
2011-01-04 19:00 ` H. Peter Anvin [this message]
2011-01-05 5:45 ` Lin Ming
2011-01-05 10:08 ` Peter Zijlstra
2011-01-04 18:55 ` Valdis.Kletnieks
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