From: Valdis.Kletnieks@vt.edu
To: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: "H. Peter Anvin" <hpa@zytor.com>, Lin Ming <ming.m.lin@intel.com>,
Ingo Molnar <mingo@elte.hu>, Andi Kleen <andi@firstfloor.org>,
Stephane Eranian <eranian@google.com>,
lkml <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH 4/7] perf: Check if HT is supported and enabled
Date: Tue, 04 Jan 2011 13:55:27 -0500 [thread overview]
Message-ID: <14831.1294167327@localhost> (raw)
In-Reply-To: Your message of "Tue, 04 Jan 2011 12:10:19 +0100." <1294139419.2016.115.camel@laptop>
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On Tue, 04 Jan 2011 12:10:19 +0100, Peter Zijlstra said:
> X86_FEATURE_HT tells us the CPU supports telling us about HT,
> smp_num_siblings > 1 tells us the CPU is capable of HT.
A subtle but important distinction. Several laptops ago, I had a P4-M chip that
had FEATURE_HT, but num_siblings == 1. ISTR trying to boot an SMP kernel on it
and it dying gloriously trying to bring up the non-existent other sibling.
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prev parent reply other threads:[~2011-01-04 18:57 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
2011-01-05 5:45 ` Lin Ming
2011-01-05 10:08 ` Peter Zijlstra
2011-01-04 18:55 ` Valdis.Kletnieks [this message]
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