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Subject: SMT_ID or APIC_ID caching
Date: Fri, 2 Sep 2005 07:55:48 -0700
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Thread-Topic: SMT_ID or APIC_ID caching
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From: "Wilkerson, Bryan P" <Bryan.P.Wilkerson@intel.com>
To: <linux-kernel@vger.kernel.org>
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On a P4 with HT, I'm trying to get the logical processor ID (SMT_ID) for
the currently executing thread in kernel mode.  The SMT_ID is part of
the APIC_ID which is in EBX[24:16] after calling cpuid with EAX=1.

Is the SMT_ID or APIC_ID per_cpu cached by the kernel anywhere?

Thanks,

-bryan