X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;ds=sidebyside;f=src%2Fthread.h;h=e71db835734d7bd2bc146b0cf71332e0d9b6ca61;hb=8d16111ffde1689d48d47ec379ba91613213183c;hp=372d4da362e50db09f6e317cf9912d90c825328d;hpb=13d8231746686118f0175111c769b55f48a6592e;p=stockfish
diff --git a/src/thread.h b/src/thread.h
index 372d4da3..606f9626 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) 2008-2015 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
@@ -17,79 +17,142 @@
along with this program. If not, see .
*/
-
-#if !defined(THREAD_H_INCLUDED)
+#ifndef THREAD_H_INCLUDED
#define THREAD_H_INCLUDED
+#include
+#include
+#include
+#include
+#include
-////
-//// Includes
-////
-
-#include
-
-#include "lock.h"
+#include "material.h"
#include "movepick.h"
+#include "pawns.h"
#include "position.h"
#include "search.h"
+struct Thread;
-////
-//// Constants and variables
-////
-
-const int MAX_THREADS = 8;
-const int MAX_ACTIVE_SPLIT_POINTS = 8;
+const size_t MAX_THREADS = 128;
+const size_t MAX_SPLITPOINTS_PER_THREAD = 8;
+const size_t MAX_SLAVES_PER_SPLITPOINT = 4;
-
-////
-//// Types
-////
+/// 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 splitPoint has been setup
- SplitPoint* parent;
+ // Const data after split point has been setup
const Position* pos;
+ Search::Stack* ss;
+ Thread* master;
Depth depth;
- bool pvNode, mateThreat;
Value beta;
- int ply;
- Move threatMove;
- SearchStack sstack[MAX_THREADS][PLY_MAX_PLUS_2];
+ int nodeType;
+ bool cutNode;
// Const pointers to shared data
- MovePicker* mp;
- SearchStack* parentSstack;
-
- // Shared data
- Lock lock;
+ MovePicker* movePicker;
+ SplitPoint* parentSplitPoint;
+
+ // Shared variable data
+ std::mutex mutex;
+ std::bitset slavesMask;
+ volatile bool allSlavesSearching;
+ volatile uint64_t nodes;
volatile Value alpha;
volatile Value bestValue;
+ volatile Move bestMove;
volatile int moveCount;
- volatile bool stopRequest;
- volatile int slaves[MAX_THREADS];
+ 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);
+
+ 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 {
+
+ Thread();
+ virtual void idle_loop();
+ bool cutoff_occurred() const;
+ bool available_to(const Thread* master) const;
+
+ 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;
};
-// 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
+/// MainThread and TimerThread are derived classes used to characterize the two
+/// special threads: the main one and the recurring timer.
+
+struct MainThread : public Thread {
+ virtual void idle_loop();
+ volatile bool thinking = true; // Avoid a race with start_thinking()
};
-struct Thread {
- uint64_t nodes;
- volatile ThreadState state;
- SplitPoint* volatile splitPoint;
- volatile int activeSplitPoints;
- SplitPoint splitPoints[MAX_ACTIVE_SPLIT_POINTS];
+struct TimerThread : public ThreadBase {
+
+ static const int Resolution = 5; // Millisec between two check_time() calls
+
+ virtual void idle_loop();
+
+ bool run = false;
+};
+
+
+/// 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.
+
+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.
+
+ MainThread* main() { return static_cast(at(0)); }
+ 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;
+ std::mutex mutex;
+ std::condition_variable sleepCondition;
+ TimerThread* timer;
};
+extern ThreadPool Threads;
-#endif // !defined(THREAD_H_INCLUDED)
+#endif // #ifndef THREAD_H_INCLUDED