X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fthread.h;h=0b112de9b0f14540d414c506f61998053ad0c72e;hp=ea645b4547fd878742135fdbaa4f7fd79647c14a;hb=e082112cfeb6a40ca592a15983cdedb0210daf3a;hpb=d3d26a94b3e501459a610b8d730394125c9afd45 diff --git a/src/thread.h b/src/thread.h index ea645b45..0b112de9 100644 --- a/src/thread.h +++ b/src/thread.h @@ -2,6 +2,7 @@ Stockfish, a UCI chess playing engine derived from Glaurung 2.1 Copyright (C) 2004-2008 Tord Romstad (Glaurung author) Copyright (C) 2008-2015 Marco Costalba, Joona Kiiski, Tord Romstad + Copyright (C) 2015-2016 Marco Costalba, Joona Kiiski, Gary Linscott, Tord Romstad Stockfish is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by @@ -32,143 +33,73 @@ #include "pawns.h" #include "position.h" #include "search.h" +#include "thread_win32.h" -struct Thread; -const size_t MAX_THREADS = 128; -const size_t MAX_SPLITPOINTS_PER_THREAD = 8; -const size_t MAX_SLAVES_PER_SPLITPOINT = 4; +/// Thread struct keeps together all the thread-related stuff. We also use +/// per-thread pawn and material hash tables so that once we get a pointer to an +/// entry its life time is unlimited and we don't have to care about someone +/// changing the entry under our feet. - -/// Spinlock class wraps low level atomic operations to provide a spin lock - -class Spinlock { - - std::atomic_int lock; - -public: - Spinlock() { lock = 1; } // Init here to workaround a bug with MSVC 2013 - void acquire() { - while (lock.fetch_sub(1, std::memory_order_acquire) != 1) - while (lock.load(std::memory_order_relaxed) <= 0) {} - } - void release() { lock.store(1, std::memory_order_release); } -}; - - -/// SplitPoint struct stores information shared by the threads searching in -/// parallel below the same split point. It is populated at splitting time. - -struct SplitPoint { - - // Const data after split point has been setup - const Position* pos; - Search::Stack* ss; - Thread* master; - Depth depth; - Value beta; - int nodeType; - bool cutNode; - - // Const pointers to shared data - MovePicker* movePicker; - SplitPoint* parentSplitPoint; - - // Shared variable data - Spinlock spinlock; - std::bitset slavesMask; - volatile bool allSlavesSearching; - volatile uint64_t nodes; - volatile Value alpha; - volatile Value bestValue; - volatile Move bestMove; - volatile int moveCount; - volatile bool cutoff; -}; - - -/// ThreadBase struct is the base of the hierarchy from where we derive all the -/// specialized thread classes. - -struct ThreadBase { - - virtual ~ThreadBase() = default; - virtual void idle_loop() = 0; - void notify_one(); - void wait_for(volatile const bool& b); +class Thread { std::thread nativeThread; - std::mutex mutex; - std::condition_variable sleepCondition; - volatile bool exit = false; -}; - - -/// Thread struct keeps together all the thread related stuff like locks, state -/// and especially split points. We also use per-thread pawn and material hash -/// tables so that once we get a pointer to an entry its life time is unlimited -/// and we don't have to care about someone changing the entry under our feet. - -struct Thread : public ThreadBase { + Mutex mutex; + ConditionVariable sleepCondition; + bool exit, searching; +public: Thread(); - virtual void idle_loop(); - bool cutoff_occurred() const; - bool available_to(const Thread* master) const; + virtual ~Thread(); + virtual void search(); + void idle_loop(); + void start_searching(bool resume = false); + void wait_for_search_finished(); + void wait(std::atomic_bool& b); - void split(Position& pos, Search::Stack* ss, Value alpha, Value beta, Value* bestValue, Move* bestMove, - Depth depth, int moveCount, MovePicker* movePicker, int nodeType, bool cutNode); - - SplitPoint splitPoints[MAX_SPLITPOINTS_PER_THREAD]; Pawns::Table pawnsTable; Material::Table materialTable; Endgames endgames; - Position* activePosition; - size_t idx; - int maxPly; - SplitPoint* volatile activeSplitPoint; - volatile size_t splitPointsSize; - volatile bool searching; + size_t idx, PVIdx; + int maxPly, callsCnt; + + Position rootPos; + Search::RootMoves rootMoves; + Depth rootDepth; + HistoryStats history; + MoveStats counterMoves; + Depth completedDepth; + std::atomic_bool resetCalls; }; -/// MainThread and TimerThread are derived classes used to characterize the two -/// special threads: the main one and the recurring timer. +/// MainThread is a derived class with a specific overload for the main thread struct MainThread : public Thread { - virtual void idle_loop(); - volatile bool thinking = true; // Avoid a race with start_thinking() -}; - -struct TimerThread : public ThreadBase { + virtual void search(); - static const int Resolution = 5; // Millisec between two check_time() calls - - virtual void idle_loop(); - - bool run = false; + bool easyMovePlayed, failedLow; + double bestMoveChanges; + Value previousScore; }; -/// ThreadPool struct handles all the threads related stuff like init, starting, -/// parking and, most importantly, launching a slave thread at a split point. -/// All the access to shared thread data is done through this class. +/// ThreadPool struct handles all the threads-related stuff like init, starting, +/// parking and, most importantly, launching a thread. All the access to threads +/// data is done through this class. struct ThreadPool : public std::vector { - void init(); // No c'tor and d'tor, threads rely on globals that should be - void exit(); // initialized and are valid during the whole thread lifetime. + void init(); // No constructor and destructor, threads rely on globals that should + void exit(); // be initialized and valid during the whole thread lifetime. MainThread* main() { return static_cast(at(0)); } + void start_thinking(const Position&, StateListPtr&, const Search::LimitsType&); void read_uci_options(); - Thread* available_slave(const Thread* master) const; - void wait_for_think_finished(); - void start_thinking(const Position&, const Search::LimitsType&, Search::StateStackPtr&); - - Depth minimumSplitDepth; - Spinlock spinlock; - std::condition_variable sleepCondition; - TimerThread* timer; + int64_t nodes_searched(); + +private: + StateListPtr setupStates; }; extern ThreadPool Threads;