Windows下获取逻辑cpu数量和cpu核数量

代码可在Windows NT下正常运行

具体API说明请参照如下文档：

GetLogicalProcessorInformation

点击打开链接

点击打开链接

点击打开链接

typedef BOOL (WINAPI *LPFN_GLPI)(PSYSTEM_LOGICAL_PROCESSOR_INFORMATION, PDWORD);

DWORD CountSetBits(ULONG_PTR bitMask)
{
    DWORD LSHIFT = sizeof(ULONG_PTR)*8 - 1;
    DWORD bitSetCount = 0;
    ULONG_PTR bitTest = (ULONG_PTR)1 << LSHIFT;
    DWORD i;

    for (i = 0; i <= LSHIFT; ++i)
    {
        bitSetCount += ((bitMask & bitTest)?1:0);
        bitTest/=2;
    }

    return bitSetCount;
}
LPFN_GLPI glpi;
glpi = (LPFN_GLPI) GetProcAddress(GetModuleHandle(TEXT("kernel32")),"GetLogicalProcessorInformation");
if (NULL == glpi)
{
    printf("GetLogicalProcessorInformation is not supported.
");
}
BOOL done = FALSE;
PSYSTEM_LOGICAL_PROCESSOR_INFORMATION buffer = NULL;
PSYSTEM_LOGICAL_PROCESSOR_INFORMATION ptr = NULL;
DWORD returnLength = 0;
while (!done)
{
    DWORD rc = glpi(buffer, &returnLength);

    if (FALSE == rc)
    {
        if (GetLastError() == ERROR_INSUFFICIENT_BUFFER)
        {
            if (buffer)
                free(buffer);

            buffer = (PSYSTEM_LOGICAL_PROCESSOR_INFORMATION)malloc(returnLength);

            if (NULL == buffer)
            {
                printf("Error: Allocation failure
");
                return (2);
            }
        }
        else
        {
            printf("Error %d
", GetLastError());
            return (3);
        }
    }
    else
    {
        done = TRUE;
    }
}

ptr = buffer;
DWORD byteOffset = 0;
DWORD logicalProcessorCount = 0;
DWORD processorCoreCount = 0;

while (byteOffset + sizeof(SYSTEM_LOGICAL_PROCESSOR_INFORMATION) <= returnLength)
{
    switch (ptr->Relationship)
    {
        case RelationProcessorCore:
            processorCoreCount++;
            logicalProcessorCount += CountSetBits(ptr->ProcessorMask);
            break;
    }
    byteOffset += sizeof(SYSTEM_LOGICAL_PROCESSOR_INFORMATION);
    ptr++;
}
printf("logical:%d  core:%d
", logicalProcessorCount, processorCoreCount);

http://blog.csdn.net/tobacco5648/article/details/22201169