diff options
Diffstat (limited to 'src/common')
| -rw-r--r-- | src/common/x64/cpu_detect.cpp | 59 | ||||
| -rw-r--r-- | src/common/x64/cpu_detect.h | 4 |
2 files changed, 60 insertions, 3 deletions
diff --git a/src/common/x64/cpu_detect.cpp b/src/common/x64/cpu_detect.cpp index 1a27532d4..e54383a4a 100644 --- a/src/common/x64/cpu_detect.cpp +++ b/src/common/x64/cpu_detect.cpp @@ -4,14 +4,27 @@ #include <array> #include <cstring> +#include <fstream> #include <iterator> +#include <optional> #include <string_view> +#include <thread> +#include <vector> #include "common/bit_util.h" #include "common/common_types.h" +#include "common/logging/log.h" #include "common/x64/cpu_detect.h" +#ifdef _WIN32 +#include <windows.h> +#endif + #ifdef _MSC_VER #include <intrin.h> + +static inline u64 xgetbv(u32 index) { + return _xgetbv(index); +} #else #if defined(__DragonFly__) || defined(__FreeBSD__) @@ -39,12 +52,11 @@ static inline void __cpuid(int info[4], u32 function_id) { } #define _XCR_XFEATURE_ENABLED_MASK 0 -static inline u64 _xgetbv(u32 index) { +static inline u64 xgetbv(u32 index) { u32 eax, edx; __asm__ __volatile__("xgetbv" : "=a"(eax), "=d"(edx) : "c"(index)); return ((u64)edx << 32) | eax; } - #endif // _MSC_VER namespace Common { @@ -107,7 +119,7 @@ static CPUCaps Detect() { // - Is the XSAVE bit set in CPUID? // - XGETBV result has the XCR bit set. if (Common::Bit<28>(cpu_id[2]) && Common::Bit<27>(cpu_id[2])) { - if ((_xgetbv(_XCR_XFEATURE_ENABLED_MASK) & 0x6) == 0x6) { + if ((xgetbv(_XCR_XFEATURE_ENABLED_MASK) & 0x6) == 0x6) { caps.avx = true; if (Common::Bit<12>(cpu_id[2])) caps.fma = true; @@ -192,4 +204,45 @@ const CPUCaps& GetCPUCaps() { return caps; } +std::optional<int> GetProcessorCount() { +#if defined(_WIN32) + // Get the buffer length. + DWORD length = 0; + GetLogicalProcessorInformation(nullptr, &length); + if (GetLastError() != ERROR_INSUFFICIENT_BUFFER) { + LOG_ERROR(Frontend, "Failed to query core count."); + return std::nullopt; + } + std::vector<SYSTEM_LOGICAL_PROCESSOR_INFORMATION> buffer( + length / sizeof(SYSTEM_LOGICAL_PROCESSOR_INFORMATION)); + // Now query the core count. + if (!GetLogicalProcessorInformation(buffer.data(), &length)) { + LOG_ERROR(Frontend, "Failed to query core count."); + return std::nullopt; + } + return static_cast<int>( + std::count_if(buffer.cbegin(), buffer.cend(), [](const auto& proc_info) { + return proc_info.Relationship == RelationProcessorCore; + })); +#elif defined(__unix__) + const int thread_count = std::thread::hardware_concurrency(); + std::ifstream smt("/sys/devices/system/cpu/smt/active"); + char state = '0'; + if (smt) { + smt.read(&state, sizeof(state)); + } + switch (state) { + case '0': + return thread_count; + case '1': + return thread_count / 2; + default: + return std::nullopt; + } +#else + // Shame on you + return std::nullopt; +#endif +} + } // namespace Common diff --git a/src/common/x64/cpu_detect.h b/src/common/x64/cpu_detect.h index 6830f3795..ca8db19d6 100644 --- a/src/common/x64/cpu_detect.h +++ b/src/common/x64/cpu_detect.h @@ -4,6 +4,7 @@ #pragma once +#include <optional> #include <string_view> #include "common/common_types.h" @@ -74,4 +75,7 @@ struct CPUCaps { */ const CPUCaps& GetCPUCaps(); +/// Detects CPU core count +std::optional<int> GetProcessorCount(); + } // namespace Common |