From mboxrd@z Thu Jan  1 00:00:00 1970
From: Wei Huang <wei.huang2@amd.com>
Subject: [PATCH][RFC][0/2] x86 SMP: enables core-pair topology
 detection for AMD CPUs
Date: Thu, 23 Jun 2011 17:51:50 -0500
Message-ID: <4E03C386.9030009@amd.com>
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To: "'xen-devel@lists.xensource.com'" <xen-devel@lists.xensource.com>, Keir Fraser <keir.xen@gmail.com>, george.dunlap@eu.citrix.com, Jan Beulich <JBeulich@novell.com>
List-Id: xen-devel@lists.xenproject.org

Hi,

The following two patches enable core-pair topology detection for AMD 
CPUs. The main idea is to record compute unit information into 
cpuinfo_x86 and use it when building sibling map. The sibling map will 
be used by Xen credit scheduler to coordinate VCPU scheduling in a 
fashion similar to SMT. This code is very similar to upstream Linux kernel.

Regarding the performance improvement, I saw ~8% improvement running 
kernel compilation on Dom0 with this patch. Anrea Przywara ran a POVRay 
benchmark using this patch and he saw ~5% improvement. No perf 
degradation was seen so far.

Please review.

Thanks,
-Wei