blob: c1969ea2d3fe8d12bc5bd85b5a9213855e668dea [file] [log] [blame]
// Copyright 2015 Google Inc. All rights reserved.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#include "internal_macros.h"
#ifdef BENCHMARK_OS_WINDOWS
#include <shlwapi.h>
#undef StrCat // Don't let StrCat in string_util.h be renamed to lstrcatA
#include <versionhelpers.h>
#include <windows.h>
#include <codecvt>
#else
#include <fcntl.h>
#ifndef BENCHMARK_OS_FUCHSIA
#include <sys/resource.h>
#endif
#include <sys/time.h>
#include <sys/types.h> // this header must be included before 'sys/sysctl.h' to avoid compilation error on FreeBSD
#include <unistd.h>
#if defined BENCHMARK_OS_FREEBSD || defined BENCHMARK_OS_MACOSX || \
defined BENCHMARK_OS_NETBSD || defined BENCHMARK_OS_OPENBSD || \
defined BENCHMARK_OS_DRAGONFLY
#define BENCHMARK_HAS_SYSCTL
#include <sys/sysctl.h>
#endif
#endif
#if defined(BENCHMARK_OS_SOLARIS)
#include <kstat.h>
#endif
#if defined(BENCHMARK_OS_QNX)
#include <sys/syspage.h>
#endif
#include <algorithm>
#include <array>
#include <bitset>
#include <cerrno>
#include <climits>
#include <cstdint>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <fstream>
#include <iostream>
#include <iterator>
#include <limits>
#include <memory>
#include <sstream>
#include <locale>
#include <utility>
#include "check.h"
#include "cycleclock.h"
#include "internal_macros.h"
#include "log.h"
#include "sleep.h"
#include "string_util.h"
namespace benchmark {
namespace {
void PrintImp(std::ostream& out) { out << std::endl; }
template <class First, class... Rest>
void PrintImp(std::ostream& out, First&& f, Rest&&... rest) {
out << std::forward<First>(f);
PrintImp(out, std::forward<Rest>(rest)...);
}
template <class... Args>
BENCHMARK_NORETURN void PrintErrorAndDie(Args&&... args) {
PrintImp(std::cerr, std::forward<Args>(args)...);
std::exit(EXIT_FAILURE);
}
#ifdef BENCHMARK_HAS_SYSCTL
/// ValueUnion - A type used to correctly alias the byte-for-byte output of
/// `sysctl` with the result type it's to be interpreted as.
struct ValueUnion {
union DataT {
uint32_t uint32_value;
uint64_t uint64_value;
// For correct aliasing of union members from bytes.
char bytes[8];
};
using DataPtr = std::unique_ptr<DataT, decltype(&std::free)>;
// The size of the data union member + its trailing array size.
size_t Size;
DataPtr Buff;
public:
ValueUnion() : Size(0), Buff(nullptr, &std::free) {}
explicit ValueUnion(size_t BuffSize)
: Size(sizeof(DataT) + BuffSize),
Buff(::new (std::malloc(Size)) DataT(), &std::free) {}
ValueUnion(ValueUnion&& other) = default;
explicit operator bool() const { return bool(Buff); }
char* data() const { return Buff->bytes; }
std::string GetAsString() const { return std::string(data()); }
int64_t GetAsInteger() const {
if (Size == sizeof(Buff->uint32_value))
return static_cast<int32_t>(Buff->uint32_value);
else if (Size == sizeof(Buff->uint64_value))
return static_cast<int64_t>(Buff->uint64_value);
BENCHMARK_UNREACHABLE();
}
uint64_t GetAsUnsigned() const {
if (Size == sizeof(Buff->uint32_value))
return Buff->uint32_value;
else if (Size == sizeof(Buff->uint64_value))
return Buff->uint64_value;
BENCHMARK_UNREACHABLE();
}
template <class T, int N>
std::array<T, N> GetAsArray() {
const int ArrSize = sizeof(T) * N;
CHECK_LE(ArrSize, Size);
std::array<T, N> Arr;
std::memcpy(Arr.data(), data(), ArrSize);
return Arr;
}
};
ValueUnion GetSysctlImp(std::string const& Name) {
#if defined BENCHMARK_OS_OPENBSD
int mib[2];
mib[0] = CTL_HW;
if ((Name == "hw.ncpu") || (Name == "hw.cpuspeed")){
ValueUnion buff(sizeof(int));
if (Name == "hw.ncpu") {
mib[1] = HW_NCPU;
} else {
mib[1] = HW_CPUSPEED;
}
if (sysctl(mib, 2, buff.data(), &buff.Size, nullptr, 0) == -1) {
return ValueUnion();
}
return buff;
}
return ValueUnion();
#else
size_t CurBuffSize = 0;
if (sysctlbyname(Name.c_str(), nullptr, &CurBuffSize, nullptr, 0) == -1)
return ValueUnion();
ValueUnion buff(CurBuffSize);
if (sysctlbyname(Name.c_str(), buff.data(), &buff.Size, nullptr, 0) == 0)
return buff;
return ValueUnion();
#endif
}
BENCHMARK_MAYBE_UNUSED
bool GetSysctl(std::string const& Name, std::string* Out) {
Out->clear();
auto Buff = GetSysctlImp(Name);
if (!Buff) return false;
Out->assign(Buff.data());
return true;
}
template <class Tp,
class = typename std::enable_if<std::is_integral<Tp>::value>::type>
bool GetSysctl(std::string const& Name, Tp* Out) {
*Out = 0;
auto Buff = GetSysctlImp(Name);
if (!Buff) return false;
*Out = static_cast<Tp>(Buff.GetAsUnsigned());
return true;
}
template <class Tp, size_t N>
bool GetSysctl(std::string const& Name, std::array<Tp, N>* Out) {
auto Buff = GetSysctlImp(Name);
if (!Buff) return false;
*Out = Buff.GetAsArray<Tp, N>();
return true;
}
#endif
template <class ArgT>
bool ReadFromFile(std::string const& fname, ArgT* arg) {
*arg = ArgT();
std::ifstream f(fname.c_str());
if (!f.is_open()) return false;
f >> *arg;
return f.good();
}
CPUInfo::Scaling CpuScaling(int num_cpus) {
// We don't have a valid CPU count, so don't even bother.
if (num_cpus <= 0) return CPUInfo::Scaling::UNKNOWN;
#ifdef BENCHMARK_OS_QNX
return CPUInfo::Scaling::UNKNOWN;
#endif
#ifndef BENCHMARK_OS_WINDOWS
// On Linux, the CPUfreq subsystem exposes CPU information as files on the
// local file system. If reading the exported files fails, then we may not be
// running on Linux, so we silently ignore all the read errors.
std::string res;
for (int cpu = 0; cpu < num_cpus; ++cpu) {
std::string governor_file =
StrCat("/sys/devices/system/cpu/cpu", cpu, "/cpufreq/scaling_governor");
if (ReadFromFile(governor_file, &res) && res != "performance") return CPUInfo::Scaling::ENABLED;
}
return CPUInfo::Scaling::DISABLED;
#endif
return CPUInfo::Scaling::UNKNOWN;
}
int CountSetBitsInCPUMap(std::string Val) {
auto CountBits = [](std::string Part) {
using CPUMask = std::bitset<sizeof(std::uintptr_t) * CHAR_BIT>;
Part = "0x" + Part;
CPUMask Mask(benchmark::stoul(Part, nullptr, 16));
return static_cast<int>(Mask.count());
};
size_t Pos;
int total = 0;
while ((Pos = Val.find(',')) != std::string::npos) {
total += CountBits(Val.substr(0, Pos));
Val = Val.substr(Pos + 1);
}
if (!Val.empty()) {
total += CountBits(Val);
}
return total;
}
BENCHMARK_MAYBE_UNUSED
std::vector<CPUInfo::CacheInfo> GetCacheSizesFromKVFS() {
std::vector<CPUInfo::CacheInfo> res;
std::string dir = "/sys/devices/system/cpu/cpu0/cache/";
int Idx = 0;
while (true) {
CPUInfo::CacheInfo info;
std::string FPath = StrCat(dir, "index", Idx++, "/");
std::ifstream f(StrCat(FPath, "size").c_str());
if (!f.is_open()) break;
std::string suffix;
f >> info.size;
if (f.fail())
PrintErrorAndDie("Failed while reading file '", FPath, "size'");
if (f.good()) {
f >> suffix;
if (f.bad())
PrintErrorAndDie(
"Invalid cache size format: failed to read size suffix");
else if (f && suffix != "K")
PrintErrorAndDie("Invalid cache size format: Expected bytes ", suffix);
else if (suffix == "K")
info.size *= 1024;
}
if (!ReadFromFile(StrCat(FPath, "type"), &info.type))
PrintErrorAndDie("Failed to read from file ", FPath, "type");
if (!ReadFromFile(StrCat(FPath, "level"), &info.level))
PrintErrorAndDie("Failed to read from file ", FPath, "level");
std::string map_str;
if (!ReadFromFile(StrCat(FPath, "shared_cpu_map"), &map_str))
PrintErrorAndDie("Failed to read from file ", FPath, "shared_cpu_map");
info.num_sharing = CountSetBitsInCPUMap(map_str);
res.push_back(info);
}
return res;
}
#ifdef BENCHMARK_OS_MACOSX
std::vector<CPUInfo::CacheInfo> GetCacheSizesMacOSX() {
std::vector<CPUInfo::CacheInfo> res;
std::array<uint64_t, 4> CacheCounts{{0, 0, 0, 0}};
GetSysctl("hw.cacheconfig", &CacheCounts);
struct {
std::string name;
std::string type;
int level;
uint64_t num_sharing;
} Cases[] = {{"hw.l1dcachesize", "Data", 1, CacheCounts[1]},
{"hw.l1icachesize", "Instruction", 1, CacheCounts[1]},
{"hw.l2cachesize", "Unified", 2, CacheCounts[2]},
{"hw.l3cachesize", "Unified", 3, CacheCounts[3]}};
for (auto& C : Cases) {
int val;
if (!GetSysctl(C.name, &val)) continue;
CPUInfo::CacheInfo info;
info.type = C.type;
info.level = C.level;
info.size = val;
info.num_sharing = static_cast<int>(C.num_sharing);
res.push_back(std::move(info));
}
return res;
}
#elif defined(BENCHMARK_OS_WINDOWS)
std::vector<CPUInfo::CacheInfo> GetCacheSizesWindows() {
std::vector<CPUInfo::CacheInfo> res;
DWORD buffer_size = 0;
using PInfo = SYSTEM_LOGICAL_PROCESSOR_INFORMATION;
using CInfo = CACHE_DESCRIPTOR;
using UPtr = std::unique_ptr<PInfo, decltype(&std::free)>;
GetLogicalProcessorInformation(nullptr, &buffer_size);
UPtr buff((PInfo*)malloc(buffer_size), &std::free);
if (!GetLogicalProcessorInformation(buff.get(), &buffer_size))
PrintErrorAndDie("Failed during call to GetLogicalProcessorInformation: ",
GetLastError());
PInfo* it = buff.get();
PInfo* end = buff.get() + (buffer_size / sizeof(PInfo));
for (; it != end; ++it) {
if (it->Relationship != RelationCache) continue;
using BitSet = std::bitset<sizeof(ULONG_PTR) * CHAR_BIT>;
BitSet B(it->ProcessorMask);
// To prevent duplicates, only consider caches where CPU 0 is specified
if (!B.test(0)) continue;
CInfo* Cache = &it->Cache;
CPUInfo::CacheInfo C;
C.num_sharing = static_cast<int>(B.count());
C.level = Cache->Level;
C.size = Cache->Size;
switch (Cache->Type) {
case CacheUnified:
C.type = "Unified";
break;
case CacheInstruction:
C.type = "Instruction";
break;
case CacheData:
C.type = "Data";
break;
case CacheTrace:
C.type = "Trace";
break;
default:
C.type = "Unknown";
break;
}
res.push_back(C);
}
return res;
}
#elif BENCHMARK_OS_QNX
std::vector<CPUInfo::CacheInfo> GetCacheSizesQNX() {
std::vector<CPUInfo::CacheInfo> res;
struct cacheattr_entry *cache = SYSPAGE_ENTRY(cacheattr);
uint32_t const elsize = SYSPAGE_ELEMENT_SIZE(cacheattr);
int num = SYSPAGE_ENTRY_SIZE(cacheattr) / elsize ;
for(int i = 0; i < num; ++i ) {
CPUInfo::CacheInfo info;
switch (cache->flags){
case CACHE_FLAG_INSTR :
info.type = "Instruction";
info.level = 1;
break;
case CACHE_FLAG_DATA :
info.type = "Data";
info.level = 1;
break;
case CACHE_FLAG_UNIFIED :
info.type = "Unified";
info.level = 2;
break;
case CACHE_FLAG_SHARED :
info.type = "Shared";
info.level = 3;
break;
default :
continue;
break;
}
info.size = cache->line_size * cache->num_lines;
info.num_sharing = 0;
res.push_back(std::move(info));
cache = SYSPAGE_ARRAY_ADJ_OFFSET(cacheattr, cache, elsize);
}
return res;
}
#endif
std::vector<CPUInfo::CacheInfo> GetCacheSizes() {
#ifdef BENCHMARK_OS_MACOSX
return GetCacheSizesMacOSX();
#elif defined(BENCHMARK_OS_WINDOWS)
return GetCacheSizesWindows();
#elif defined(BENCHMARK_OS_QNX)
return GetCacheSizesQNX();
#else
return GetCacheSizesFromKVFS();
#endif
}
std::string GetSystemName() {
#if defined(BENCHMARK_OS_WINDOWS)
std::string str;
const unsigned COUNT = MAX_COMPUTERNAME_LENGTH+1;
TCHAR hostname[COUNT] = {'\0'};
DWORD DWCOUNT = COUNT;
if (!GetComputerName(hostname, &DWCOUNT))
return std::string("");
#ifndef UNICODE
str = std::string(hostname, DWCOUNT);
#else
//Using wstring_convert, Is deprecated in C++17
using convert_type = std::codecvt_utf8<wchar_t>;
std::wstring_convert<convert_type, wchar_t> converter;
std::wstring wStr(hostname, DWCOUNT);
str = converter.to_bytes(wStr);
#endif
return str;
#else // defined(BENCHMARK_OS_WINDOWS)
#ifndef HOST_NAME_MAX
#ifdef BENCHMARK_HAS_SYSCTL // BSD/Mac Doesnt have HOST_NAME_MAX defined
#define HOST_NAME_MAX 64
#elif defined(BENCHMARK_OS_NACL)
#define HOST_NAME_MAX 64
#elif defined(BENCHMARK_OS_QNX)
#define HOST_NAME_MAX 154
#elif defined(BENCHMARK_OS_RTEMS)
#define HOST_NAME_MAX 256
#else
#warning "HOST_NAME_MAX not defined. using 64"
#define HOST_NAME_MAX 64
#endif
#endif // def HOST_NAME_MAX
char hostname[HOST_NAME_MAX];
int retVal = gethostname(hostname, HOST_NAME_MAX);
if (retVal != 0) return std::string("");
return std::string(hostname);
#endif // Catch-all POSIX block.
}
int GetNumCPUs() {
#ifdef BENCHMARK_HAS_SYSCTL
int NumCPU = -1;
if (GetSysctl("hw.ncpu", &NumCPU)) return NumCPU;
fprintf(stderr, "Err: %s\n", strerror(errno));
std::exit(EXIT_FAILURE);
#elif defined(BENCHMARK_OS_WINDOWS)
SYSTEM_INFO sysinfo;
// Use memset as opposed to = {} to avoid GCC missing initializer false
// positives.
std::memset(&sysinfo, 0, sizeof(SYSTEM_INFO));
GetSystemInfo(&sysinfo);
return sysinfo.dwNumberOfProcessors; // number of logical
// processors in the current
// group
#elif defined(BENCHMARK_OS_SOLARIS)
// Returns -1 in case of a failure.
int NumCPU = sysconf(_SC_NPROCESSORS_ONLN);
if (NumCPU < 0) {
fprintf(stderr,
"sysconf(_SC_NPROCESSORS_ONLN) failed with error: %s\n",
strerror(errno));
}
return NumCPU;
#elif defined(BENCHMARK_OS_QNX)
return static_cast<int>(_syspage_ptr->num_cpu);
#else
int NumCPUs = 0;
int MaxID = -1;
std::ifstream f("/proc/cpuinfo");
if (!f.is_open()) {
std::cerr << "failed to open /proc/cpuinfo\n";
return -1;
}
const std::string Key = "processor";
std::string ln;
while (std::getline(f, ln)) {
if (ln.empty()) continue;
size_t SplitIdx = ln.find(':');
std::string value;
#if defined(__s390__)
// s390 has another format in /proc/cpuinfo
// it needs to be parsed differently
if (SplitIdx != std::string::npos) value = ln.substr(Key.size()+1,SplitIdx-Key.size()-1);
#else
if (SplitIdx != std::string::npos) value = ln.substr(SplitIdx + 1);
#endif
if (ln.size() >= Key.size() && ln.compare(0, Key.size(), Key) == 0) {
NumCPUs++;
if (!value.empty()) {
int CurID = benchmark::stoi(value);
MaxID = std::max(CurID, MaxID);
}
}
}
if (f.bad()) {
std::cerr << "Failure reading /proc/cpuinfo\n";
return -1;
}
if (!f.eof()) {
std::cerr << "Failed to read to end of /proc/cpuinfo\n";
return -1;
}
f.close();
if ((MaxID + 1) != NumCPUs) {
fprintf(stderr,
"CPU ID assignments in /proc/cpuinfo seem messed up."
" This is usually caused by a bad BIOS.\n");
}
return NumCPUs;
#endif
BENCHMARK_UNREACHABLE();
}
double GetCPUCyclesPerSecond(CPUInfo::Scaling scaling) {
// Currently, scaling is only used on linux path here,
// suppress diagnostics about it being unused on other paths.
(void)scaling;
#if defined BENCHMARK_OS_LINUX || defined BENCHMARK_OS_CYGWIN
long freq;
// If the kernel is exporting the tsc frequency use that. There are issues
// where cpuinfo_max_freq cannot be relied on because the BIOS may be
// exporintg an invalid p-state (on x86) or p-states may be used to put the
// processor in a new mode (turbo mode). Essentially, those frequencies
// cannot always be relied upon. The same reasons apply to /proc/cpuinfo as
// well.
if (ReadFromFile("/sys/devices/system/cpu/cpu0/tsc_freq_khz", &freq)
// If CPU scaling is disabled, use the the *current* frequency.
// Note that we specifically don't want to read cpuinfo_cur_freq,
// because it is only readable by root.
|| (scaling == CPUInfo::Scaling::DISABLED &&
ReadFromFile("/sys/devices/system/cpu/cpu0/cpufreq/scaling_cur_freq",
&freq))
// Otherwise, if CPU scaling may be in effect, we want to use
// the *maximum* frequency, not whatever CPU speed some random processor
// happens to be using now.
|| ReadFromFile("/sys/devices/system/cpu/cpu0/cpufreq/cpuinfo_max_freq",
&freq)) {
// The value is in kHz (as the file name suggests). For example, on a
// 2GHz warpstation, the file contains the value "2000000".
return freq * 1000.0;
}
const double error_value = -1;
double bogo_clock = error_value;
std::ifstream f("/proc/cpuinfo");
if (!f.is_open()) {
std::cerr << "failed to open /proc/cpuinfo\n";
return error_value;
}
auto startsWithKey = [](std::string const& Value, std::string const& Key) {
if (Key.size() > Value.size()) return false;
auto Cmp = [&](char X, char Y) {
return std::tolower(X) == std::tolower(Y);
};
return std::equal(Key.begin(), Key.end(), Value.begin(), Cmp);
};
std::string ln;
while (std::getline(f, ln)) {
if (ln.empty()) continue;
size_t SplitIdx = ln.find(':');
std::string value;
if (SplitIdx != std::string::npos) value = ln.substr(SplitIdx + 1);
// When parsing the "cpu MHz" and "bogomips" (fallback) entries, we only
// accept positive values. Some environments (virtual machines) report zero,
// which would cause infinite looping in WallTime_Init.
if (startsWithKey(ln, "cpu MHz")) {
if (!value.empty()) {
double cycles_per_second = benchmark::stod(value) * 1000000.0;
if (cycles_per_second > 0) return cycles_per_second;
}
} else if (startsWithKey(ln, "bogomips")) {
if (!value.empty()) {
bogo_clock = benchmark::stod(value) * 1000000.0;
if (bogo_clock < 0.0) bogo_clock = error_value;
}
}
}
if (f.bad()) {
std::cerr << "Failure reading /proc/cpuinfo\n";
return error_value;
}
if (!f.eof()) {
std::cerr << "Failed to read to end of /proc/cpuinfo\n";
return error_value;
}
f.close();
// If we found the bogomips clock, but nothing better, we'll use it (but
// we're not happy about it); otherwise, fallback to the rough estimation
// below.
if (bogo_clock >= 0.0) return bogo_clock;
#elif defined BENCHMARK_HAS_SYSCTL
constexpr auto* FreqStr =
#if defined(BENCHMARK_OS_FREEBSD) || defined(BENCHMARK_OS_NETBSD)
"machdep.tsc_freq";
#elif defined BENCHMARK_OS_OPENBSD
"hw.cpuspeed";
#elif defined BENCHMARK_OS_DRAGONFLY
"hw.tsc_frequency";
#else
"hw.cpufrequency";
#endif
unsigned long long hz = 0;
#if defined BENCHMARK_OS_OPENBSD
if (GetSysctl(FreqStr, &hz)) return hz * 1000000;
#else
if (GetSysctl(FreqStr, &hz)) return hz;
#endif
fprintf(stderr, "Unable to determine clock rate from sysctl: %s: %s\n",
FreqStr, strerror(errno));
#elif defined BENCHMARK_OS_WINDOWS
// In NT, read MHz from the registry. If we fail to do so or we're in win9x
// then make a crude estimate.
DWORD data, data_size = sizeof(data);
if (IsWindowsXPOrGreater() &&
SUCCEEDED(
SHGetValueA(HKEY_LOCAL_MACHINE,
"HARDWARE\\DESCRIPTION\\System\\CentralProcessor\\0",
"~MHz", nullptr, &data, &data_size)))
return static_cast<double>((int64_t)data *
(int64_t)(1000 * 1000)); // was mhz
#elif defined (BENCHMARK_OS_SOLARIS)
kstat_ctl_t *kc = kstat_open();
if (!kc) {
std::cerr << "failed to open /dev/kstat\n";
return -1;
}
kstat_t *ksp = kstat_lookup(kc, (char*)"cpu_info", -1, (char*)"cpu_info0");
if (!ksp) {
std::cerr << "failed to lookup in /dev/kstat\n";
return -1;
}
if (kstat_read(kc, ksp, NULL) < 0) {
std::cerr << "failed to read from /dev/kstat\n";
return -1;
}
kstat_named_t *knp =
(kstat_named_t*)kstat_data_lookup(ksp, (char*)"current_clock_Hz");
if (!knp) {
std::cerr << "failed to lookup data in /dev/kstat\n";
return -1;
}
if (knp->data_type != KSTAT_DATA_UINT64) {
std::cerr << "current_clock_Hz is of unexpected data type: "
<< knp->data_type << "\n";
return -1;
}
double clock_hz = knp->value.ui64;
kstat_close(kc);
return clock_hz;
#elif defined (BENCHMARK_OS_QNX)
return static_cast<double>((int64_t)(SYSPAGE_ENTRY(cpuinfo)->speed) *
(int64_t)(1000 * 1000));
#endif
// If we've fallen through, attempt to roughly estimate the CPU clock rate.
const int estimate_time_ms = 1000;
const auto start_ticks = cycleclock::Now();
SleepForMilliseconds(estimate_time_ms);
return static_cast<double>(cycleclock::Now() - start_ticks);
}
std::vector<double> GetLoadAvg() {
#if (defined BENCHMARK_OS_FREEBSD || defined(BENCHMARK_OS_LINUX) || \
defined BENCHMARK_OS_MACOSX || defined BENCHMARK_OS_NETBSD || \
defined BENCHMARK_OS_OPENBSD || defined BENCHMARK_OS_DRAGONFLY) && \
!defined(__ANDROID__)
constexpr int kMaxSamples = 3;
std::vector<double> res(kMaxSamples, 0.0);
const int nelem = getloadavg(res.data(), kMaxSamples);
if (nelem < 1) {
res.clear();
} else {
res.resize(nelem);
}
return res;
#else
return {};
#endif
}
} // end namespace
const CPUInfo& CPUInfo::Get() {
static const CPUInfo* info = new CPUInfo();
return *info;
}
CPUInfo::CPUInfo()
: num_cpus(GetNumCPUs()),
scaling(CpuScaling(num_cpus)),
cycles_per_second(GetCPUCyclesPerSecond(scaling)),
caches(GetCacheSizes()),
load_avg(GetLoadAvg()) {}
const SystemInfo& SystemInfo::Get() {
static const SystemInfo* info = new SystemInfo();
return *info;
}
SystemInfo::SystemInfo() : name(GetSystemName()) {}
} // end namespace benchmark