Properly count number of logical processors on Intel CPUs.

The meaning of the 25-14 bits in EAX returned from cpuid with EAX = 4
has been changed from "the maximum number of threads sharing the cache"
to "the maximum number of addressable IDs for logical processors sharing
the cache" if cpuid takes EAX = 11.  We need to use results from both
EAX = 4 and EAX = 11 to get the number of threads sharing the cache.

The 25-14 bits in EAX on Core i7 is 15 although the number of logical
processors is 8.  Here is a white paper on this:

http://software.intel.com/en-us/articles/intel-64-architecture-processor-topology-enumeration/

This patch correctly counts number of logical processors on Intel CPUs
with EAX = 11 support on cpuid.  Tested on Dinnington, Core i7 and
Nehalem EX/EP.

It also fixed Pentium Ds workaround since EBX may not have the right
value returned from cpuid with EAX = 1.

1 files changed, 5 insertions, 0 deletions

diff --git a/ChangeLog b/ChangeLog
index c6169d776e..debf530fab 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+2009-08-05  H.J. Lu  <hongjiu.lu@intel.com>
+
+	* sysdeps/x86_64/cacheinfo.c (init_cacheinfo): Properly use
+	EBX from EAX = 1.  Handle EAX = 11.
+
 2009-08-07  Andreas Schwab  <schwab@redhat.com>
 
 	* Makefile (TAGS): Use separate sed -e expressions to avoid \