X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fthread.h;h=d24b65dc7700a1a33b492c103b01a1a4527f0093;hp=e5a198c88e764902d74ff6f509c4ef4075cefbb5;hb=b8c5ea869ca80338f8b2fa6815fc92349b889750;hpb=339e1b49f619ceffa75019e196adf4de74b32cce diff --git a/src/thread.h b/src/thread.h index e5a198c8..d24b65dc 100644 --- a/src/thread.h +++ b/src/thread.h @@ -1,7 +1,7 @@ /* 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) 2008-2012 Marco Costalba, Joona Kiiski, 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 @@ -20,116 +20,156 @@ #if !defined(THREAD_H_INCLUDED) #define THREAD_H_INCLUDED -#include +#include -#include "lock.h" #include "material.h" #include "movepick.h" #include "pawns.h" #include "position.h" +#include "search.h" -const int MAX_THREADS = 32; -const int MAX_ACTIVE_SPLIT_POINTS = 8; +const int MAX_THREADS = 64; // Because SplitPoint::slavesMask is a uint64_t +const int MAX_SPLITPOINTS_PER_THREAD = 8; + +struct Mutex { + Mutex() { lock_init(l); } + ~Mutex() { lock_destroy(l); } + + void lock() { lock_grab(l); } + void unlock() { lock_release(l); } + +private: + friend struct ConditionVariable; + + Lock l; +}; + +struct ConditionVariable { + ConditionVariable() { cond_init(c); } + ~ConditionVariable() { cond_destroy(c); } + + void wait(Mutex& m) { cond_wait(c, m.l); } + void wait_for(Mutex& m, int ms) { timed_wait(c, m.l, ms); } + void notify_one() { cond_signal(c); } + +private: + WaitCondition c; +}; + +struct Thread; struct SplitPoint { - // Const data after splitPoint has been setup - SplitPoint* parent; + // Const data after split point has been setup const Position* pos; + const Search::Stack* ss; + Thread* masterThread; Depth depth; - bool pvNode; Value beta; - int ply; - int master; + int nodeType; Move threatMove; // Const pointers to shared data - MovePicker* mp; - SearchStack* ss; + MovePicker* movePicker; + SplitPoint* parentSplitPoint; // Shared data - Lock lock; + Mutex mutex; + Position* slavesPositions[MAX_THREADS]; + volatile uint64_t slavesMask; volatile int64_t nodes; volatile Value alpha; volatile Value bestValue; + volatile Move bestMove; volatile int moveCount; - volatile bool betaCutoff; - volatile int slaves[MAX_THREADS]; -}; - -// ThreadState type is used to represent thread's current state -enum ThreadState -{ - THREAD_INITIALIZING, // thread is initializing itself - THREAD_SEARCHING, // thread is performing work - THREAD_AVAILABLE, // thread is waiting for work - THREAD_BOOKED, // other thread (master) has booked us as a slave - THREAD_WORKISWAITING, // master has ordered us to start - THREAD_TERMINATED // we are quitting and thread is terminated + volatile bool cutoff; }; -// We 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. +/// 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 { - MaterialInfoTable materialTable; - PawnInfoTable pawnTable; + + Thread(); + virtual ~Thread(); + + virtual void idle_loop(); + void notify_one(); + bool cutoff_occurred() const; + bool is_available_to(Thread* master) const; + void wait_for(volatile const bool& b); + + SplitPoint splitPoints[MAX_SPLITPOINTS_PER_THREAD]; + Material::Table materialTable; + Endgames endgames; + Pawns::Table pawnsTable; + size_t idx; int maxPly; - Lock sleepLock; - WaitCondition sleepCond; - volatile ThreadState state; - SplitPoint* volatile splitPoint; - volatile int activeSplitPoints; - SplitPoint splitPoints[MAX_ACTIVE_SPLIT_POINTS]; - - void wake_up() { - lock_grab(&sleepLock); - cond_signal(&sleepCond); - lock_release(&sleepLock); - } + Mutex mutex; + ConditionVariable sleepCondition; + NativeHandle handle; + SplitPoint* volatile activeSplitPoint; + volatile int splitPointsSize; + volatile bool searching; + volatile bool exit; +}; + + +/// MainThread and TimerThread are sublassed from Thread to characterize the two +/// special threads: the main one and the recurring timer. + +struct MainThread : public Thread { + MainThread() : thinking(true) {} // Avoid a race with start_thinking() + virtual void idle_loop(); + volatile bool thinking; +}; + +struct TimerThread : public Thread { + TimerThread() : msec(0) {} + virtual void idle_loop(); + int msec; }; -// ThreadsManager class is used to handle all the threads related stuff like init, -// starting, parking and, the most important, launching a slave thread at a split -// point. All the access to shared thread data is done through this class. +/// ThreadPool class handles all the threads related stuff like init, starting, +/// parking and, the most important, launching a slave thread at a split point. +/// All the access to shared thread data is done through this class. + +class ThreadPool { -class ThreadsManager { - /* As long as the single ThreadsManager object is defined as a global we don't - need to explicitly initialize to zero its data members because variables with - static storage duration are automatically set to zero before enter main() - */ public: - Thread& operator[](int threadID) { return threads[threadID]; } - void init_threads(); - void exit_threads(); - void init_hash_tables(); + void init(); // No c'tor and d'tor, threads rely on globals that should + void exit(); // be initialized and valid during the whole thread lifetime. - int min_split_depth() const { return minimumSplitDepth; } - int active_threads() const { return activeThreads; } - void set_active_threads(int cnt) { activeThreads = cnt; } + Thread& operator[](size_t id) { return *threads[id]; } + size_t size() const { return threads.size(); } + MainThread* main_thread() { return static_cast(threads[0]); } + TimerThread* timer_thread() { return timer; } void read_uci_options(); - bool available_thread_exists(int master) const; - bool thread_is_available(int slave, int master) const; - bool cutoff_at_splitpoint(int threadID) const; - void idle_loop(int threadID, SplitPoint* sp); + bool slave_available(Thread* master) const; + void wait_for_think_finished(); + void start_thinking(const Position&, const Search::LimitsType&, + const std::vector&, Search::StateStackPtr&); template - void split(Position& pos, SearchStack* ss, Value* alpha, const Value beta, Value* bestValue, - Depth depth, Move threatMove, int moveCount, MovePicker* mp, bool pvNode); -private: - Lock mpLock; + Value split(Position& pos, Search::Stack* ss, Value alpha, Value beta, Value bestValue, Move* bestMove, + Depth depth, Move threatMove, int moveCount, MovePicker& mp, int nodeType); + + bool sleepWhileIdle; Depth minimumSplitDepth; - int maxThreadsPerSplitPoint; - bool useSleepingThreads; - int activeThreads; - volatile bool allThreadsShouldExit; - Thread threads[MAX_THREADS]; + Mutex mutex; + ConditionVariable sleepCondition; + +private: + std::vector threads; + TimerThread* timer; + size_t maxThreadsPerSplitPoint; }; -extern ThreadsManager ThreadsMgr; +extern ThreadPool Threads; #endif // !defined(THREAD_H_INCLUDED)