mirror of
https://sourceware.org/git/glibc.git
synced 2024-12-23 11:20:07 +00:00
a546baa9cd
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. |
||
---|---|---|
.. | ||
generic | ||
gnu | ||
i386 | ||
ia64 | ||
ieee754 | ||
mach | ||
posix | ||
powerpc | ||
pthread | ||
s390 | ||
sh | ||
sparc | ||
unix | ||
wordsize-32 | ||
wordsize-64 | ||
x86_64 |