Files
Xenia-Canary/src/xenia/core/pal_win.cc
2014-08-16 16:57:00 -07:00

147 lines
4.3 KiB
C++

/**
******************************************************************************
* Xenia : Xbox 360 Emulator Research Project *
******************************************************************************
* Copyright 2013 Ben Vanik. All rights reserved. *
* Released under the BSD license - see LICENSE in the root for more details. *
******************************************************************************
*/
#include <xenia/core/pal.h>
#include <algorithm>
namespace {
typedef struct xe_pal_win {
bool use_high_perf_timer;
double inv_ticks_per_sec;
} xe_pal_win_t;
xe_pal_win_t* pal;
}
void xe_pal_dealloc();
int xe_pal_init(xe_pal_options_t options) {
pal = (xe_pal_win_t*)xe_calloc(sizeof(xe_pal_win_t));
// Get QPC timing frequency... hopefully stable over the life of the app,
// but likely not.
// TODO(benvanik): requery periodically/etc.
LARGE_INTEGER ticks_per_sec;
if (QueryPerformanceFrequency(&ticks_per_sec)) {
pal->use_high_perf_timer = true;
pal->inv_ticks_per_sec = 1.0 / (double)ticks_per_sec.QuadPart;
} else {
pal->use_high_perf_timer = false;
XELOGW("Falling back from high performance timer");
}
// Setup COM on the main thread.
// NOTE: this may fail if COM has already been initialized - that's OK.
CoInitializeEx(NULL, COINIT_MULTITHREADED);
atexit(xe_pal_dealloc);
return 0;
}
void xe_pal_dealloc() {
//
xe_free(pal);
}
// http://msdn.microsoft.com/en-us/library/ms683194.aspx
namespace {
DWORD CountSetBits(ULONG_PTR bitMask) {
DWORD LSHIFT = sizeof(ULONG_PTR)*8 - 1;
DWORD bitSetCount = 0;
ULONG_PTR bitTest = (ULONG_PTR)1 << LSHIFT;
for (DWORD i = 0; i <= LSHIFT; ++i, bitTest /= 2) {
bitSetCount += ((bitMask & bitTest)?1:0);
}
return bitSetCount;
}
}
int xe_pal_get_system_info(xe_system_info* out_info) {
int result_code = 1;
xe_zero_struct(out_info, sizeof(xe_system_info));
out_info->processors.physical_count = 1;
out_info->processors.logical_count = 1;
typedef BOOL (WINAPI *LPFN_GLPI)(
PSYSTEM_LOGICAL_PROCESSOR_INFORMATION, PDWORD);
HMODULE kernel32 = NULL;
LPFN_GLPI glpi = NULL;
PSYSTEM_LOGICAL_PROCESSOR_INFORMATION buffer = NULL;
kernel32 = GetModuleHandle(L"kernel32");
XEEXPECTNOTNULL(kernel32);
glpi = (LPFN_GLPI)GetProcAddress(kernel32, "GetLogicalProcessorInformation");
XEEXPECTNOTNULL(glpi);
// Call GLPI once to get the buffer size, allocate it, then call again.
DWORD buffer_length = 0;
XEEXPECTFALSE(glpi(NULL, &buffer_length));
XEEXPECT(GetLastError() == ERROR_INSUFFICIENT_BUFFER);
buffer = (PSYSTEM_LOGICAL_PROCESSOR_INFORMATION)xe_malloc(buffer_length);
XEEXPECTNOTNULL(buffer);
XEEXPECTTRUE(glpi(buffer, &buffer_length));
XEEXPECTNOTZERO(buffer_length);
out_info->processors.physical_count = 0;
out_info->processors.logical_count = 0;
size_t info_count = buffer_length /
sizeof(SYSTEM_LOGICAL_PROCESSOR_INFORMATION);
for (size_t n = 0; n < info_count; n++) {
switch (buffer[n].Relationship) {
case RelationProcessorPackage:
out_info->processors.physical_count++;
break;
case RelationProcessorCore:
if (buffer[n].ProcessorCore.Flags == 1) {
// Hyper-threaded.
// The number of processors is set as bits in ProcessorMask.
out_info->processors.logical_count +=
CountSetBits(buffer[n].ProcessorMask);
} else {
// A real core - just count as one.
out_info->processors.logical_count++;
}
break;
}
}
out_info->processors.physical_count =
std::max(1u, out_info->processors.physical_count);
out_info->processors.logical_count =
std::max(1u, out_info->processors.logical_count);
result_code = 0;
XECLEANUP:
xe_free(buffer);
if (kernel32) {
FreeLibrary(kernel32);
}
return result_code;
}
double xe_pal_now() {
if (pal->use_high_perf_timer) {
LARGE_INTEGER counter;
QueryPerformanceCounter(&counter);
return counter.QuadPart * pal->inv_ticks_per_sec;
} else {
// Using GetSystemTimeAsFileTime instead of GetSystemTime() as it has a
// 100ns resolution.
FILETIME ft;
GetSystemTimeAsFileTime(&ft);
ULARGE_INTEGER uli;
uli.LowPart = ft.dwLowDateTime;
uli.HighPart = ft.dwHighDateTime;
return uli.QuadPart / 10000000.0;
}
}