X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fthread.h;h=f69012aeb0a3053130b85abada02704b7781d531;hp=87b78136f5c7851b992327cdc03d65205c7becc2;hb=27c5cb59127101d834636d4faa0062d4e7bd05ce;hpb=a4a0ffce711962c0b04b35998c3c06491be373bf

diff --git a/src/thread.h b/src/thread.h
index 87b78136..fd7343a8 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 +17,107 @@
   along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 
-
-#if !defined(THREAD_H_INCLUDED)
+#ifndef THREAD_H_INCLUDED
 #define THREAD_H_INCLUDED
 
+#include <atomic>
+#include <bitset>
+#include <condition_variable>
+#include <mutex>
+#include <thread>
+#include <vector>
 
-////
-//// Includes
-////
-
-#include <cstring>
-
-#include "lock.h"
+#include "material.h"
 #include "movepick.h"
+#include "pawns.h"
 #include "position.h"
 #include "search.h"
+#include "thread_win32.h"
+
+
+/// ThreadBase struct is the base of the hierarchy from where we derive all the
+/// specialized thread classes.
+
+struct ThreadBase : public std::thread {
+
+  ThreadBase() { exit = false; }
+  virtual ~ThreadBase() = default;
+  virtual void idle_loop() = 0;
+  void notify_one();
+  void wait(std::atomic<bool>& b);
+  void wait_while(std::atomic<bool>& b);
+
+  Mutex mutex;
+  ConditionVariable sleepCondition;
+  std::atomic<bool> exit;
+};
 
 
-////
-//// Constants and variables
-////
+/// Thread struct keeps together all the thread related stuff like locks, state,
+/// history and countermoves tables. 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.
 
-const int MAX_THREADS = 8;
-const int ACTIVE_SPLIT_POINTS_MAX = 8;
+struct Thread : public ThreadBase {
 
+  Thread();
+  virtual void idle_loop();
+  void search(bool isMainThread = false);
 
-////
-//// Types
-////
+  Pawns::Table pawnsTable;
+  Material::Table materialTable;
+  Endgames endgames;
+  size_t idx, PVIdx;
+  int maxPly;
+  std::atomic<bool> searching;
 
-struct SplitPoint {
+  Position rootPos;
+  Search::RootMoveVector rootMoves;
+  Depth rootDepth;
+  HistoryStats history;
+  MovesStats counterMoves;
+  Depth completedDepth;
+};
 
-  // Const data after splitPoint has been setup
-  SplitPoint* parent;
-  const Position* pos;
-  Depth depth;
-  bool pvNode, mateThreat;
-  Value beta;
-  int ply, master, slaves[MAX_THREADS];
-  SearchStack sstack[MAX_THREADS][PLY_MAX_PLUS_2];
 
-  // Const pointers to shared data
-  MovePicker* mp;
-  SearchStack* parentSstack;
+/// MainThread and TimerThread are derived classes used to characterize the two
+/// special threads: the main one and the recurring timer.
 
-  // Shared data
-  Lock lock;
-  volatile Value alpha;
-  volatile Value bestValue;
-  volatile int moves;
-  volatile int cpus;
-  volatile bool stopRequest;
+struct MainThread : public Thread {
+  MainThread() { thinking = true; } // Avoid a race with start_thinking()
+  virtual void idle_loop();
+  void join();
+  void think();
+  std::atomic<bool> thinking;
 };
 
-// ThreadState type is used to represent thread's current state
+struct TimerThread : public ThreadBase {
+
+  static const int Resolution = 5; // Millisec between two check_time() calls
+
+  virtual void idle_loop();
+  void check_time();
 
-enum ThreadState
-{
-  THREAD_SEARCHING,     // thread is performing work
-  THREAD_AVAILABLE,     // thread is polling for work
-  THREAD_SLEEPING,      // we are not thinking, so thread is sleeping
-  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
+  bool run = false;
 };
 
-struct Thread {
-  SplitPoint* splitPoint;
-  volatile int activeSplitPoints;
-  uint64_t nodes;
-  uint64_t betaCutOffs[2];
-  volatile ThreadState state;
-  unsigned char pad[64]; // set some distance among local data for each thread
+
+/// ThreadPool struct handles all the threads related stuff like init, starting,
+/// parking and, most importantly, launching a thread.
+/// All the access to shared thread data is done through this class.
+
+struct ThreadPool : public std::vector<Thread*> {
+
+  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<MainThread*>(at(0)); }
+  void read_uci_options();
+  void start_thinking(const Position&, const Search::LimitsType&, Search::StateStackPtr&);
+  int64_t nodes_searched();
+  TimerThread* timer;
 };
 
+extern ThreadPool Threads;
 
-#endif // !defined(THREAD_H_INCLUDED)
+#endif // #ifndef THREAD_H_INCLUDED