/*
Stockfish, a UCI chess playing engine derived from Glaurung 2.1
- Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
- Copyright (C) 2008-2010 Marco Costalba, Joona Kiiski, Tord Romstad
+ Copyright (C) 2004-2020 The Stockfish developers (see AUTHORS file)
Stockfish is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
+#ifdef _WIN32
+#if _WIN32_WINNT < 0x0601
+#undef _WIN32_WINNT
+#define _WIN32_WINNT 0x0601 // Force to include needed API prototypes
+#endif
-////
-//// Includes
-////
-
-#if !defined(_MSC_VER)
-
-# include <sys/time.h>
-# include <sys/types.h>
-# include <unistd.h>
-# if defined(__hpux)
-# include <sys/pstat.h>
-# endif
-
-#else
+#ifndef NOMINMAX
+#define NOMINMAX
+#endif
-#define _CRT_SECURE_NO_DEPRECATE
#include <windows.h>
-#include <sys/timeb.h>
-
+// The needed Windows API for processor groups could be missed from old Windows
+// versions, so instead of calling them directly (forcing the linker to resolve
+// the calls at compile time), try to load them at runtime. To do this we need
+// first to define the corresponding function pointers.
+extern "C" {
+typedef bool(*fun1_t)(LOGICAL_PROCESSOR_RELATIONSHIP,
+ PSYSTEM_LOGICAL_PROCESSOR_INFORMATION_EX, PDWORD);
+typedef bool(*fun2_t)(USHORT, PGROUP_AFFINITY);
+typedef bool(*fun3_t)(HANDLE, CONST GROUP_AFFINITY*, PGROUP_AFFINITY);
+}
#endif
-#include <cassert>
-#include <cstdio>
+#include <fstream>
#include <iomanip>
#include <iostream>
#include <sstream>
+#include <vector>
+#include <cstdlib>
+
+#if defined(__linux__) && !defined(__ANDROID__)
+#include <stdlib.h>
+#include <sys/mman.h>
+#endif
+
+#if defined(__APPLE__) || defined(__ANDROID__) || defined(__OpenBSD__) || (defined(__GLIBCXX__) && !defined(_GLIBCXX_HAVE_ALIGNED_ALLOC) && !defined(_WIN32))
+#define POSIXALIGNEDALLOC
+#include <stdlib.h>
+#endif
-#include "bitcount.h"
#include "misc.h"
#include "thread.h"
using namespace std;
-/// Version number. If this is left empty, the current date (in the format
-/// YYMMDD) is used as a version number.
+namespace {
-static const string EngineVersion = "1.7";
-static const string AppName = "Stockfish";
-static const string AppTag = "";
+/// Version number. If Version is left empty, then compile date in the format
+/// DD-MM-YY and show in engine_info.
+const string Version = "";
+/// Our fancy logging facility. The trick here is to replace cin.rdbuf() and
+/// cout.rdbuf() with two Tie objects that tie cin and cout to a file stream. We
+/// can toggle the logging of std::cout and std:cin at runtime whilst preserving
+/// usual I/O functionality, all without changing a single line of code!
+/// Idea from http://groups.google.com/group/comp.lang.c++/msg/1d941c0f26ea0d81
-////
-//// Variables
-////
+struct Tie: public streambuf { // MSVC requires split streambuf for cin and cout
-bool Chess960;
+ Tie(streambuf* b, streambuf* l) : buf(b), logBuf(l) {}
-uint64_t dbg_cnt0 = 0;
-uint64_t dbg_cnt1 = 0;
+ int sync() override { return logBuf->pubsync(), buf->pubsync(); }
+ int overflow(int c) override { return log(buf->sputc((char)c), "<< "); }
+ int underflow() override { return buf->sgetc(); }
+ int uflow() override { return log(buf->sbumpc(), ">> "); }
-bool dbg_show_mean = false;
-bool dbg_show_hit_rate = false;
+ streambuf *buf, *logBuf;
+ int log(int c, const char* prefix) {
-////
-//// Functions
-////
+ static int last = '\n'; // Single log file
-void dbg_hit_on(bool b) {
+ if (last == '\n')
+ logBuf->sputn(prefix, 3);
- assert(!dbg_show_mean);
- dbg_show_hit_rate = true;
- dbg_cnt0++;
- if (b)
- dbg_cnt1++;
-}
+ return last = logBuf->sputc((char)c);
+ }
+};
-void dbg_hit_on_c(bool c, bool b) {
+class Logger {
- if (c)
- dbg_hit_on(b);
-}
+ Logger() : in(cin.rdbuf(), file.rdbuf()), out(cout.rdbuf(), file.rdbuf()) {}
+ ~Logger() { start(""); }
+
+ ofstream file;
+ Tie in, out;
+
+public:
+ static void start(const std::string& fname) {
+
+ static Logger l;
+
+ if (!fname.empty() && !l.file.is_open())
+ {
+ l.file.open(fname, ifstream::out);
+
+ if (!l.file.is_open())
+ {
+ cerr << "Unable to open debug log file " << fname << endl;
+ exit(EXIT_FAILURE);
+ }
+
+ cin.rdbuf(&l.in);
+ cout.rdbuf(&l.out);
+ }
+ else if (fname.empty() && l.file.is_open())
+ {
+ cout.rdbuf(l.out.buf);
+ cin.rdbuf(l.in.buf);
+ l.file.close();
+ }
+ }
+};
-void dbg_before() {
+} // namespace
- assert(!dbg_show_mean);
- dbg_show_hit_rate = true;
- dbg_cnt0++;
+/// engine_info() returns the full name of the current Stockfish version. This
+/// will be either "Stockfish <Tag> DD-MM-YY" (where DD-MM-YY is the date when
+/// the program was compiled) or "Stockfish <Version>", depending on whether
+/// Version is empty.
+
+const string engine_info(bool to_uci) {
+
+ const string months("Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec");
+ string month, day, year;
+ stringstream ss, date(__DATE__); // From compiler, format is "Sep 21 2008"
+
+ ss << "Stockfish " << Version << setfill('0');
+
+ if (Version.empty())
+ {
+ date >> month >> day >> year;
+ ss << setw(2) << day << setw(2) << (1 + months.find(month) / 4) << year.substr(2);
+ }
+
+ ss << (to_uci ? "\nid author ": " by ")
+ << "the Stockfish developers (see AUTHORS file)";
+
+ return ss.str();
}
-void dbg_after() {
- assert(!dbg_show_mean);
- dbg_show_hit_rate = true;
- dbg_cnt1++;
+/// compiler_info() returns a string trying to describe the compiler we use
+
+const std::string compiler_info() {
+
+ #define stringify2(x) #x
+ #define stringify(x) stringify2(x)
+ #define make_version_string(major, minor, patch) stringify(major) "." stringify(minor) "." stringify(patch)
+
+/// Predefined macros hell:
+///
+/// __GNUC__ Compiler is gcc, Clang or Intel on Linux
+/// __INTEL_COMPILER Compiler is Intel
+/// _MSC_VER Compiler is MSVC or Intel on Windows
+/// _WIN32 Building on Windows (any)
+/// _WIN64 Building on Windows 64 bit
+
+ std::string compiler = "\nCompiled by ";
+
+ #ifdef __clang__
+ compiler += "clang++ ";
+ compiler += make_version_string(__clang_major__, __clang_minor__, __clang_patchlevel__);
+ #elif __INTEL_COMPILER
+ compiler += "Intel compiler ";
+ compiler += "(version ";
+ compiler += stringify(__INTEL_COMPILER) " update " stringify(__INTEL_COMPILER_UPDATE);
+ compiler += ")";
+ #elif _MSC_VER
+ compiler += "MSVC ";
+ compiler += "(version ";
+ compiler += stringify(_MSC_FULL_VER) "." stringify(_MSC_BUILD);
+ compiler += ")";
+ #elif __GNUC__
+ compiler += "g++ (GNUC) ";
+ compiler += make_version_string(__GNUC__, __GNUC_MINOR__, __GNUC_PATCHLEVEL__);
+ #else
+ compiler += "Unknown compiler ";
+ compiler += "(unknown version)";
+ #endif
+
+ #if defined(__APPLE__)
+ compiler += " on Apple";
+ #elif defined(__CYGWIN__)
+ compiler += " on Cygwin";
+ #elif defined(__MINGW64__)
+ compiler += " on MinGW64";
+ #elif defined(__MINGW32__)
+ compiler += " on MinGW32";
+ #elif defined(__ANDROID__)
+ compiler += " on Android";
+ #elif defined(__linux__)
+ compiler += " on Linux";
+ #elif defined(_WIN64)
+ compiler += " on Microsoft Windows 64-bit";
+ #elif defined(_WIN32)
+ compiler += " on Microsoft Windows 32-bit";
+ #else
+ compiler += " on unknown system";
+ #endif
+
+ compiler += "\nCompilation settings include: ";
+ compiler += (Is64Bit ? " 64bit" : " 32bit");
+ #if defined(USE_VNNI)
+ compiler += " VNNI";
+ #endif
+ #if defined(USE_AVX512)
+ compiler += " AVX512";
+ #endif
+ compiler += (HasPext ? " BMI2" : "");
+ #if defined(USE_AVX2)
+ compiler += " AVX2";
+ #endif
+ #if defined(USE_SSE41)
+ compiler += " SSE41";
+ #endif
+ #if defined(USE_SSSE3)
+ compiler += " SSSE3";
+ #endif
+ #if defined(USE_SSE2)
+ compiler += " SSE2";
+ #endif
+ compiler += (HasPopCnt ? " POPCNT" : "");
+ #if defined(USE_MMX)
+ compiler += " MMX";
+ #endif
+
+ #if !defined(NDEBUG)
+ compiler += " DEBUG";
+ #endif
+
+ compiler += "\n__VERSION__ macro expands to: ";
+ #ifdef __VERSION__
+ compiler += __VERSION__;
+ #else
+ compiler += "(undefined macro)";
+ #endif
+ compiler += "\n";
+
+ return compiler;
}
-void dbg_mean_of(int v) {
- assert(!dbg_show_hit_rate);
- dbg_show_mean = true;
- dbg_cnt0++;
- dbg_cnt1 += v;
+/// Debug functions used mainly to collect run-time statistics
+static std::atomic<int64_t> hits[2], means[2];
+
+void dbg_hit_on(bool b) { ++hits[0]; if (b) ++hits[1]; }
+void dbg_hit_on(bool c, bool b) { if (c) dbg_hit_on(b); }
+void dbg_mean_of(int v) { ++means[0]; means[1] += v; }
+
+void dbg_print() {
+
+ if (hits[0])
+ cerr << "Total " << hits[0] << " Hits " << hits[1]
+ << " hit rate (%) " << 100 * hits[1] / hits[0] << endl;
+
+ if (means[0])
+ cerr << "Total " << means[0] << " Mean "
+ << (double)means[1] / means[0] << endl;
}
-void dbg_print_hit_rate() {
- cout << "Total " << dbg_cnt0 << " Hit " << dbg_cnt1
- << " hit rate (%) " << (dbg_cnt1*100)/(dbg_cnt0 ? dbg_cnt0 : 1) << endl;
+/// Used to serialize access to std::cout to avoid multiple threads writing at
+/// the same time.
+
+std::ostream& operator<<(std::ostream& os, SyncCout sc) {
+
+ static std::mutex m;
+
+ if (sc == IO_LOCK)
+ m.lock();
+
+ if (sc == IO_UNLOCK)
+ m.unlock();
+
+ return os;
}
-void dbg_print_mean() {
- cout << "Total " << dbg_cnt0 << " Mean "
- << (float)dbg_cnt1 / (dbg_cnt0 ? dbg_cnt0 : 1) << endl;
+/// Trampoline helper to avoid moving Logger to misc.h
+void start_logger(const std::string& fname) { Logger::start(fname); }
+
+
+/// prefetch() preloads the given address in L1/L2 cache. This is a non-blocking
+/// function that doesn't stall the CPU waiting for data to be loaded from memory,
+/// which can be quite slow.
+#ifdef NO_PREFETCH
+
+void prefetch(void*) {}
+
+#else
+
+void prefetch(void* addr) {
+
+# if defined(__INTEL_COMPILER)
+ // This hack prevents prefetches from being optimized away by
+ // Intel compiler. Both MSVC and gcc seem not be affected by this.
+ __asm__ ("");
+# endif
+
+# if defined(__INTEL_COMPILER) || defined(_MSC_VER)
+ _mm_prefetch((char*)addr, _MM_HINT_T0);
+# else
+ __builtin_prefetch(addr);
+# endif
}
-void dbg_print_hit_rate(ofstream& logFile) {
+#endif
+
+/// Wrappers for systems where the c++17 implementation doesn't guarantee the availability of aligned_alloc.
+/// Memory allocated with std_aligned_alloc must be freed with std_aligned_free.
+///
+
+void* std_aligned_alloc(size_t alignment, size_t size) {
+#if defined(POSIXALIGNEDALLOC)
+ void *pointer;
+ if(posix_memalign(&pointer, alignment, size) == 0)
+ return pointer;
+ return nullptr;
+#elif defined(_WIN32)
+ return _mm_malloc(size, alignment);
+#else
+ return std::aligned_alloc(alignment, size);
+#endif
+}
- logFile << "Total " << dbg_cnt0 << " Hit " << dbg_cnt1
- << " hit rate (%) " << (dbg_cnt1*100)/(dbg_cnt0 ? dbg_cnt0 : 1) << endl;
+void std_aligned_free(void* ptr) {
+#if defined(POSIXALIGNEDALLOC)
+ free(ptr);
+#elif defined(_WIN32)
+ _mm_free(ptr);
+#else
+ free(ptr);
+#endif
}
-void dbg_print_mean(ofstream& logFile) {
+/// aligned_ttmem_alloc() will return suitably aligned memory, and if possible use large pages.
+/// The returned pointer is the aligned one, while the mem argument is the one that needs
+/// to be passed to free. With c++17 some of this functionality could be simplified.
- logFile << "Total " << dbg_cnt0 << " Mean "
- << (float)dbg_cnt1 / (dbg_cnt0 ? dbg_cnt0 : 1) << endl;
+#if defined(__linux__) && !defined(__ANDROID__)
+
+void* aligned_ttmem_alloc(size_t allocSize, void*& mem) {
+
+ constexpr size_t alignment = 2 * 1024 * 1024; // assumed 2MB page sizes
+ size_t size = ((allocSize + alignment - 1) / alignment) * alignment; // multiple of alignment
+ if (posix_memalign(&mem, alignment, size))
+ mem = nullptr;
+ madvise(mem, allocSize, MADV_HUGEPAGE);
+ return mem;
}
-/// engine_name() returns the full name of the current Stockfish version.
-/// This will be either "Stockfish YYMMDD" (where YYMMDD is the date when the
-/// program was compiled) or "Stockfish <version number>", depending on whether
-/// the constant EngineVersion (defined in misc.h) is empty.
+#elif defined(_WIN64)
+
+static void* aligned_ttmem_alloc_large_pages(size_t allocSize) {
-const string engine_name() {
+ HANDLE hProcessToken { };
+ LUID luid { };
+ void* mem = nullptr;
- const string cpu64(CpuHas64BitPath ? " 64bit" : "");
+ const size_t largePageSize = GetLargePageMinimum();
+ if (!largePageSize)
+ return nullptr;
- if (!EngineVersion.empty())
- return AppName+ " " + EngineVersion + cpu64;
+ // We need SeLockMemoryPrivilege, so try to enable it for the process
+ if (!OpenProcessToken(GetCurrentProcess(), TOKEN_ADJUST_PRIVILEGES | TOKEN_QUERY, &hProcessToken))
+ return nullptr;
- string date(__DATE__); // From compiler, format is "Sep 21 2008"
- string months("Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec");
+ if (LookupPrivilegeValue(NULL, SE_LOCK_MEMORY_NAME, &luid))
+ {
+ TOKEN_PRIVILEGES tp { };
+ TOKEN_PRIVILEGES prevTp { };
+ DWORD prevTpLen = 0;
- size_t mon = 1 + months.find(date.substr(0, 3)) / 4;
+ tp.PrivilegeCount = 1;
+ tp.Privileges[0].Luid = luid;
+ tp.Privileges[0].Attributes = SE_PRIVILEGE_ENABLED;
- stringstream s;
- string day = (date[4] == ' ' ? date.substr(5, 1) : date.substr(4, 2));
+ // Try to enable SeLockMemoryPrivilege. Note that even if AdjustTokenPrivileges() succeeds,
+ // we still need to query GetLastError() to ensure that the privileges were actually obtained.
+ if (AdjustTokenPrivileges(
+ hProcessToken, FALSE, &tp, sizeof(TOKEN_PRIVILEGES), &prevTp, &prevTpLen) &&
+ GetLastError() == ERROR_SUCCESS)
+ {
+ // Round up size to full pages and allocate
+ allocSize = (allocSize + largePageSize - 1) & ~size_t(largePageSize - 1);
+ mem = VirtualAlloc(
+ NULL, allocSize, MEM_RESERVE | MEM_COMMIT | MEM_LARGE_PAGES, PAGE_READWRITE);
- string name = AppName + " " + AppTag + " ";
+ // Privilege no longer needed, restore previous state
+ AdjustTokenPrivileges(hProcessToken, FALSE, &prevTp, 0, NULL, NULL);
+ }
+ }
- s << name << date.substr(date.length() - 2) << setfill('0')
- << setw(2) << mon << setw(2) << day << cpu64;
+ CloseHandle(hProcessToken);
- return s.str();
+ return mem;
}
+void* aligned_ttmem_alloc(size_t allocSize, void*& mem) {
-/// get_system_time() returns the current system time, measured in
-/// milliseconds.
+ static bool firstCall = true;
-int get_system_time() {
+ // Try to allocate large pages
+ mem = aligned_ttmem_alloc_large_pages(allocSize);
+
+ // Suppress info strings on the first call. The first call occurs before 'uci'
+ // is received and in that case this output confuses some GUIs.
+ if (!firstCall)
+ {
+ if (mem)
+ sync_cout << "info string Hash table allocation: Windows large pages used." << sync_endl;
+ else
+ sync_cout << "info string Hash table allocation: Windows large pages not used." << sync_endl;
+ }
+ firstCall = false;
+
+ // Fall back to regular, page aligned, allocation if necessary
+ if (!mem)
+ mem = VirtualAlloc(NULL, allocSize, MEM_RESERVE | MEM_COMMIT, PAGE_READWRITE);
+
+ return mem;
+}
-#if defined(_MSC_VER)
- struct _timeb t;
- _ftime(&t);
- return int(t.time*1000 + t.millitm);
#else
- struct timeval t;
- gettimeofday(&t, NULL);
- return t.tv_sec*1000 + t.tv_usec/1000;
-#endif
+
+void* aligned_ttmem_alloc(size_t allocSize, void*& mem) {
+
+ constexpr size_t alignment = 64; // assumed cache line size
+ size_t size = allocSize + alignment - 1; // allocate some extra space
+ mem = malloc(size);
+ void* ret = reinterpret_cast<void*>((uintptr_t(mem) + alignment - 1) & ~uintptr_t(alignment - 1));
+ return ret;
}
+#endif
-/// cpu_count() tries to detect the number of CPU cores.
-#if !defined(_MSC_VER)
+/// aligned_ttmem_free() will free the previously allocated ttmem
-# if defined(_SC_NPROCESSORS_ONLN)
-int cpu_count() {
- return Min(sysconf(_SC_NPROCESSORS_ONLN), MAX_THREADS);
-}
-# elif defined(__hpux)
-int cpu_count() {
- struct pst_dynamic psd;
- if (pstat_getdynamic(&psd, sizeof(psd), (size_t)1, 0) == -1)
- return 1;
+#if defined(_WIN64)
- return Min(psd.psd_proc_cnt, MAX_THREADS);
-}
-# else
-int cpu_count() {
- return 1;
+void aligned_ttmem_free(void* mem) {
+
+ if (mem && !VirtualFree(mem, 0, MEM_RELEASE))
+ {
+ DWORD err = GetLastError();
+ std::cerr << "Failed to free transposition table. Error code: 0x" <<
+ std::hex << err << std::dec << std::endl;
+ exit(EXIT_FAILURE);
+ }
}
-# endif
#else
-int cpu_count() {
- SYSTEM_INFO s;
- GetSystemInfo(&s);
- return Min(s.dwNumberOfProcessors, MAX_THREADS);
+void aligned_ttmem_free(void *mem) {
+ free(mem);
}
#endif
-/*
- From Beowulf, from Olithink
-*/
+namespace WinProcGroup {
+
#ifndef _WIN32
-/* Non-windows version */
-int Bioskey()
-{
- fd_set readfds;
- struct timeval timeout;
-
- FD_ZERO(&readfds);
- FD_SET(fileno(stdin), &readfds);
- /* Set to timeout immediately */
- timeout.tv_sec = 0;
- timeout.tv_usec = 0;
- select(16, &readfds, 0, 0, &timeout);
-
- return (FD_ISSET(fileno(stdin), &readfds));
-}
+
+void bindThisThread(size_t) {}
#else
-/* Windows-version */
-#include <windows.h>
-#include <conio.h>
-int Bioskey()
-{
- static int init = 0,
- pipe;
- static HANDLE inh;
- DWORD dw;
- /* If we're running under XBoard then we can't use _kbhit() as the input
- * commands are sent to us directly over the internal pipe */
-
-#if defined(FILE_CNT)
- if (stdin->_cnt > 0)
- return stdin->_cnt;
-#endif
- if (!init) {
- init = 1;
- inh = GetStdHandle(STD_INPUT_HANDLE);
- pipe = !GetConsoleMode(inh, &dw);
- if (!pipe) {
- SetConsoleMode(inh, dw & ~(ENABLE_MOUSE_INPUT | ENABLE_WINDOW_INPUT));
- FlushConsoleInputBuffer(inh);
- }
- }
- if (pipe) {
- if (!PeekNamedPipe(inh, NULL, 0, NULL, &dw, NULL))
- return 1;
- return dw;
- } else {
- // Count the number of unread input records, including keyboard,
- // mouse, and window-resizing input records.
- GetNumberOfConsoleInputEvents(inh, &dw);
- if (dw <= 0)
- return 0;
-
- // Read data from console without removing it from the buffer
- INPUT_RECORD rec[256];
- DWORD recCnt;
- if (!PeekConsoleInput(inh, rec, Min(dw, 256), &recCnt))
- return 0;
-
- // Search for at least one keyboard event
- for (DWORD i = 0; i < recCnt; i++)
- if (rec[i].EventType == KEY_EVENT)
- return 1;
-
- return 0;
- }
+
+/// best_group() retrieves logical processor information using Windows specific
+/// API and returns the best group id for the thread with index idx. Original
+/// code from Texel by Peter Ă–sterlund.
+
+int best_group(size_t idx) {
+
+ int threads = 0;
+ int nodes = 0;
+ int cores = 0;
+ DWORD returnLength = 0;
+ DWORD byteOffset = 0;
+
+ // Early exit if the needed API is not available at runtime
+ HMODULE k32 = GetModuleHandle("Kernel32.dll");
+ auto fun1 = (fun1_t)(void(*)())GetProcAddress(k32, "GetLogicalProcessorInformationEx");
+ if (!fun1)
+ return -1;
+
+ // First call to get returnLength. We expect it to fail due to null buffer
+ if (fun1(RelationAll, nullptr, &returnLength))
+ return -1;
+
+ // Once we know returnLength, allocate the buffer
+ SYSTEM_LOGICAL_PROCESSOR_INFORMATION_EX *buffer, *ptr;
+ ptr = buffer = (SYSTEM_LOGICAL_PROCESSOR_INFORMATION_EX*)malloc(returnLength);
+
+ // Second call, now we expect to succeed
+ if (!fun1(RelationAll, buffer, &returnLength))
+ {
+ free(buffer);
+ return -1;
+ }
+
+ while (byteOffset < returnLength)
+ {
+ if (ptr->Relationship == RelationNumaNode)
+ nodes++;
+
+ else if (ptr->Relationship == RelationProcessorCore)
+ {
+ cores++;
+ threads += (ptr->Processor.Flags == LTP_PC_SMT) ? 2 : 1;
+ }
+
+ assert(ptr->Size);
+ byteOffset += ptr->Size;
+ ptr = (SYSTEM_LOGICAL_PROCESSOR_INFORMATION_EX*)(((char*)ptr) + ptr->Size);
+ }
+
+ free(buffer);
+
+ std::vector<int> groups;
+
+ // Run as many threads as possible on the same node until core limit is
+ // reached, then move on filling the next node.
+ for (int n = 0; n < nodes; n++)
+ for (int i = 0; i < cores / nodes; i++)
+ groups.push_back(n);
+
+ // In case a core has more than one logical processor (we assume 2) and we
+ // have still threads to allocate, then spread them evenly across available
+ // nodes.
+ for (int t = 0; t < threads - cores; t++)
+ groups.push_back(t % nodes);
+
+ // If we still have more threads than the total number of logical processors
+ // then return -1 and let the OS to decide what to do.
+ return idx < groups.size() ? groups[idx] : -1;
}
+
+
+/// bindThisThread() set the group affinity of the current thread
+
+void bindThisThread(size_t idx) {
+
+ // Use only local variables to be thread-safe
+ int group = best_group(idx);
+
+ if (group == -1)
+ return;
+
+ // Early exit if the needed API are not available at runtime
+ HMODULE k32 = GetModuleHandle("Kernel32.dll");
+ auto fun2 = (fun2_t)(void(*)())GetProcAddress(k32, "GetNumaNodeProcessorMaskEx");
+ auto fun3 = (fun3_t)(void(*)())GetProcAddress(k32, "SetThreadGroupAffinity");
+
+ if (!fun2 || !fun3)
+ return;
+
+ GROUP_AFFINITY affinity;
+ if (fun2(group, &affinity))
+ fun3(GetCurrentThread(), &affinity, nullptr);
+}
+
#endif
+
+} // namespace WinProcGroup