Intel architecture ia-32 사용자 설명서
Vol. 3A 7-43
MULTIPLE-PROCESSOR MANAGEMENT
Example 7-3
Compute the Number of Packages, Cores, and Processor Relationships
in a MP System
in a MP System
a) Assemble lists of PACKAGE_ID, CORE_ID, and SMT_ID of each enabled logical processors
//The BIOS and/or OS may limit the number of logical processors available to applications
// after system boot. The below algorithm will compute topology for the processors visible
// to the thread that is computing it.
// after system boot. The below algorithm will compute topology for the processors visible
// to the thread that is computing it.
// Extract the 3-levels of IDs on every processor
// SystemAffinity is a bitmask of all the processors started by the OS. Use OS specific APIs to
obtain it.
// ThreadAffinityMask is used to affinitize the topology enumeration thread to each processor
using OS specific APIs.
// Allocate per processor arrays to store the Package_ID, Core_ID and SMT_ID for every
started processor
// SystemAffinity is a bitmask of all the processors started by the OS. Use OS specific APIs to
obtain it.
// ThreadAffinityMask is used to affinitize the topology enumeration thread to each processor
using OS specific APIs.
// Allocate per processor arrays to store the Package_ID, Core_ID and SMT_ID for every
started processor
ThreadAffinityMask = 1;
ProcessorNum = 0;
while (ThreadAffinityMask != 0 && ThreadAffinityMask <= SystemAffinity) {
// Check to make sure we can utilize this processor first.
if (ThreadAffinityMask & SystemAffinity){
if (ThreadAffinityMask & SystemAffinity){
Set thread to run on the processor specified in ThreadAffinityMask
Wait if necessary and ensure thread is running on specified processor
Wait if necessary and ensure thread is running on specified processor
InitAPIC_ID = GetInitAPIC_ID();
Extract the Package, Core and SMT ID as explained in three level extraction
Extract the Package, Core and SMT ID as explained in three level extraction
algorithm
PackageID[ProcessorNUM] = PACKAGE_ID;
CoreID[ProcessorNum] = CORE_ID;
SmtID[ProcessorNum] = SMT_ID;
ProcessorNum++;
CoreID[ProcessorNum] = CORE_ID;
SmtID[ProcessorNum] = SMT_ID;
ProcessorNum++;
}
ThreadAffinityMask <<= 1;
ThreadAffinityMask <<= 1;
}
NumStartedLPs = ProcessorNum;
NumStartedLPs = ProcessorNum;
b) Using the list of PACKAGE_ID to count the number of physical packages in a MP system
and construct, for each package, a multi-bit mask corresponging to those logical processors
residing in the same package.
and construct, for each package, a multi-bit mask corresponging to those logical processors
residing in the same package.
// Compute the number of packages by counting the number of processors
// with unique PACKAGE_IDs in the PackageID array.
// Compute the mask of processors in each package.
// with unique PACKAGE_IDs in the PackageID array.
// Compute the mask of processors in each package.
PackageIDBucket is an array of unique PACKAGE_ID values. Allocate an array of
NumStartedLPs count of entries in this array.
PackageProcessorMask is a corresponding array of the bit mask of processors belonging to
the same package, these are processors with the same PACKAGE_ID
NumStartedLPs count of entries in this array.
PackageProcessorMask is a corresponding array of the bit mask of processors belonging to
the same package, these are processors with the same PACKAGE_ID