wslapi.def

EXPORTS
	WslLaunch

wslfsbench.cpp

#define WIN32_LEAN_AND_MEAN
#include <windows.h>
#include <wslapi.h>
#include <algorithm>
#include <cstdio>
#include <cstdlib>
#include <numeric>
#include <string>
#include <vector>
#pragma comment(lib, "wslapi.lib")// Make yourself

int wmain(int, PWSTR argv[])
{
	LoadLibraryW(LR"(C:\Windows\System32\lxss\LxssManagerProxyStub.dll)");
	SC_HANDLE scm = OpenSCManagerW(nullptr, nullptr, SC_MANAGER_CONNECT);
	if (!scm)
	{
		fprintf(stderr, "!scm %08lx\n", GetLastError());
		ExitProcess(EXIT_FAILURE);
	}
	SC_HANDLE lxss = OpenServiceW(scm, L"LxssManager", SERVICE_QUERY_STATUS | SERVICE_START | SERVICE_STOP);
	if (!lxss)
	{
		fprintf(stderr, "!lxss %08lx\n", GetLastError());
		ExitProcess(EXIT_FAILURE);
	}

	SECURITY_ATTRIBUTES sa = { sizeof sa, nullptr, TRUE };
	HANDLE nul = CreateFileW(L"NUL", GENERIC_READ | GENERIC_WRITE, 0, &sa, OPEN_EXISTING, 0, nullptr);
	if (nul == INVALID_HANDLE_VALUE)
	{
		fprintf(stderr, "!nul %08lx\n", GetLastError());
		ExitProcess(EXIT_FAILURE);
	}
	HANDLE process;
	if (HRESULT result = WslLaunch(L"Ubuntu", argv[1], TRUE, nul, nul, nul, &process); FAILED(result))
	{
		fprintf(stderr, "!WslLaunch %08lx\n", result);
		ExitProcess(EXIT_FAILURE);
	}
	if (WaitForSingleObject(process, INFINITE) == WAIT_FAILED)
	{
		fprintf(stderr, "!WaitForSingleObject %08lx\n", GetLastError());
		ExitProcess(EXIT_FAILURE);
	}

	std::vector<UINT64> results;
	results.resize(std::stoi(argv[2]));
	for (auto& e : results)
	{
		SERVICE_STATUS status;
		if (!ControlService(lxss, SERVICE_CONTROL_STOP, &status))
		{
			fprintf(stderr, "!ControlService %08lx\n", GetLastError());
			ExitProcess(EXIT_FAILURE);
		}
		Sleep(1);
		do
		{
			if (!QueryServiceStatus(lxss, &status))
			{
				fprintf(stderr, "!QueryServiceStatus %08lx\n", GetLastError());
				ExitProcess(EXIT_FAILURE);
			}
			if (status.dwCurrentState == SERVICE_STOPPED)
			{
				break;
			}
			else if (status.dwCurrentState == SERVICE_STOP_PENDING)
			{
				Sleep(1);
			}
			else
			{
				fprintf(stderr, "unexpected service state %u\n", status.dwCurrentState);
				ExitProcess(EXIT_FAILURE);
			}
		} while (status.dwCurrentState != SERVICE_STOPPED);
		if (HRESULT result = WslLaunch(L"Ubuntu", argv[1], TRUE, nul, nul, nul, &process); FAILED(result))
		{
			fprintf(stderr, "!WslLaunch %08lx\n", result);
			ExitProcess(EXIT_FAILURE);
		}
		if (WaitForSingleObject(process, INFINITE) == WAIT_FAILED)
		{
			fprintf(stderr, "!WaitForSingleObject %08lx\n", GetLastError());
			ExitProcess(EXIT_FAILURE);
		}
		if (!QueryProcessCycleTime(process, &e))
		{
			fprintf(stderr, "!QueryProcessCycleTime %08lx\n", GetLastError());
			ExitProcess(EXIT_FAILURE);
		}
		CloseHandle(process);
	}
	auto[fastest, worst] = std::minmax_element(std::cbegin(results), std::cend(results));
	printf(
		"Fastest %llu\n"
		"Worst   %llu\n"
		"Average %llu\n",
		*fastest,
		*worst,
		std::accumulate(std::cbegin(results), std::cend(results), 0ULL) / results.size()
	);
}