X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fthread.h;h=786c5b677c1934a2dfd0c9aa6ab09870f87b052b;hp=372d4da362e50db09f6e317cf9912d90c825328d;hb=1a414cd9cb274d9572c60fe4067671cd993ffb36;hpb=5b445cdf59d0737befad9750cd49da0ca278c0f7

diff --git a/src/thread.h b/src/thread.h
index 372d4da3..786c5b67 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
@@ -17,79 +17,151 @@
   along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 
-
 #if !defined(THREAD_H_INCLUDED)
 #define THREAD_H_INCLUDED
 
+#include <vector>
 
-////
-//// Includes
-////
-
-#include <cstring>
-
-#include "lock.h"
+#include "material.h"
 #include "movepick.h"
+#include "pawns.h"
 #include "position.h"
 #include "search.h"
 
+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;
 
-////
-//// Constants and variables
-////
+  Lock l;
+};
+
+struct ConditionVariable {
+  ConditionVariable() { cond_init(c); }
+ ~ConditionVariable() { cond_destroy(c); }
 
-const int MAX_THREADS = 8;
-const int MAX_ACTIVE_SPLIT_POINTS = 8;
+  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;
+};
 
-////
-//// Types
-////
+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, mateThreat;
   Value beta;
-  int ply;
+  int nodeType;
   Move threatMove;
-  SearchStack sstack[MAX_THREADS][PLY_MAX_PLUS_2];
 
   // Const pointers to shared data
-  MovePicker* mp;
-  SearchStack* parentSstack;
+  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 stopRequest;
-  volatile int slaves[MAX_THREADS];
+  volatile bool cutoff;
 };
 
-// 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
-};
+/// 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 {
-  uint64_t nodes;
-  volatile ThreadState state;
-  SplitPoint* volatile splitPoint;
-  volatile int activeSplitPoints;
-  SplitPoint splitPoints[MAX_ACTIVE_SPLIT_POINTS];
+
+  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);
+
+  template <bool Fake>
+  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);
+
+  SplitPoint splitPoints[MAX_SPLITPOINTS_PER_THREAD];
+  Material::Table materialTable;
+  Endgames endgames;
+  Pawns::Table pawnsTable;
+  size_t idx;
+  int maxPly;
+  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;
+};
+
+
+/// ThreadPool struct 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.
+
+struct ThreadPool : public std::vector<Thread*> {
+
+  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.
+
+  MainThread* main_thread() { return static_cast<MainThread*>((*this)[0]); }
+  void read_uci_options();
+  bool slave_available(Thread* master) const;
+  void wait_for_think_finished();
+  void start_thinking(const Position&, const Search::LimitsType&,
+                      const std::vector<Move>&, Search::StateStackPtr&);
+
+  bool sleepWhileIdle;
+  Depth minimumSplitDepth;
+  size_t maxThreadsPerSplitPoint;
+  Mutex mutex;
+  ConditionVariable sleepCondition;
+  TimerThread* timer;
 };
 
+extern ThreadPool Threads;
 
 #endif // !defined(THREAD_H_INCLUDED)