Fixed get count threads for multiprocessor system with NUMA architecture

[GermanAizek]

Fixed very old problem that only on any Windows NT and modern Windows Server 😆

https://developercommunity.visualstudio.com/t/hardware-concurrency-returns-an-incorrect-result/350854

https://stackoverflow.com/questions/31209256/reliable-way-to-programmatically-get-the-number-of-hardware-threads-on-windows

Why this commit is useful not only for server configurations, now a very cheap PC configuration is building from Xeon E54xx, X34xx, E3-xxxx, E5-xxxx, E7-xxx, any Silver, any Gold, any Platinum series, cheapest on LGA 2011v3 socket two-socket board with NUMA support is cheap on Aliexpress, Baidu or Alibaba.

https://aliexpress.ru/item/1005004510711777.html

[Xottab-DUTY]

Do you have NUMA yourself and have any problems with OpenXRay?
Oh, this is actually a pull request, not an issue, sorry :D

[Xottab-DUTY]

This function should be defined in _math.h and _math.cpp instead.

[GermanAizek]

fix it 7218c71

[Xottab-DUTY]

It's better to just name this function something like GetThreadsCounts and place it into CPU namespace in _math.h and use it instead of std::thread::hardware_concurrency()); – that means we also should create a Linux, etc. version of this function.

[GermanAizek]

fix it 7218c71

[Nakilon]

I wish people were saying "physical/logical cores", not "threads". It's so confusing and grows people illiterate IMHO.

[Hrusteckiy]

numa numa numa ei

[375gnu]

Suggested change

	if (concurrency == 0)
	return std::thread::hardware_concurrency();
	else
	return concurrency;
	return concurrency == 0 ? std::thread::hardware_concurrency() : concurrency;

[GermanAizek]

fix it 7dc0960

[GermanAizek]

@Xottab-DUTY you can do a code review

[GermanAizek]

@Xottab-DUTY,
More optimized variant detection NUMA and return count threads on host, must added before GetLogicalProcessorInformationEx:

    if (!IsNUMA())
        return single_cpu_concurrency();

    if (GetLogicalProcessorInformationEx(RelationAll, nullptr, &length) != FALSE)
    {
        return single_cpu_concurrency();
    }

bool IsNUMA() noexcept
{
    ULONG HighestNodeNumber;
    return !(!GetNumaHighestNodeNumber(&HighestNodeNumber) || HighestNodeNumber == 0);
}

[Xottab-DUTY]

Platform-specific code is generally unwanted if we can use standard C++ functionality and/or SDL.
I'm not sure if C++ and SDL has the functionality proposed in this PR, so this PR may actually be useful, but I'm closing this PR along with banning (second time) it's author due to his disrespect to repository maintainers (almost all his PRs were submitted in broken state and/or with questionable changes, while rejecting to fix his own PRs, along with pinging me personally without any reason).