Use a timer to avoid polling

[stockfish] / src / thread.h

diff --git a/src/thread.h b/src/thread.h
index 3b539aa86e66cb88e4179e6f295d9758e273cf5e..46ce03aa318c07ea1d66a29a6439b886d4e496c0 100644 (file)
--- a/src/thread.h
+++ b/src/thread.h
@@ -23,9 +23,10 @@
 #include <cstring>
 
 #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;
@@ -36,8 +37,8 @@ struct SplitPoint {
   SplitPoint* parent;
   const Position* pos;
   Depth depth;
-  bool pvNode;
   Value beta;
+  int nodeType;
   int ply;
   int master;
   Move threatMove;
@@ -52,28 +53,89 @@ struct SplitPoint {
   volatile Value alpha;
   volatile Value bestValue;
   volatile int moveCount;
-  volatile bool betaCutoff;
-  volatile int slaves[MAX_THREADS];
+  volatile bool is_betaCutoff;
+  volatile bool is_slave[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
-};
+
+/// Thread struct is used to keep 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 {
+
+  void wake_up();
+  bool cutoff_occurred() const;
+  bool is_available_to(int master) const;
+  void idle_loop(SplitPoint* sp);
+  void listener_loop();
+  void timer_loop();
+
+  SplitPoint splitPoints[MAX_ACTIVE_SPLIT_POINTS];
+  MaterialInfoTable materialTable;
+  PawnInfoTable pawnTable;
+  int threadID;
+  int maxPly;
   Lock sleepLock;
   WaitCondition sleepCond;
-  volatile ThreadState state;
   SplitPoint* volatile splitPoint;
   volatile int activeSplitPoints;
-  SplitPoint splitPoints[MAX_ACTIVE_SPLIT_POINTS];
+  volatile bool is_searching;
+  volatile bool do_sleep;
+  volatile bool do_terminate;
+
+#if defined(_MSC_VER)
+  HANDLE handle;
+#else
+  pthread_t handle;
+#endif
+};
+
+
+/// 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.
+
+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();
+  void exit();
+
+  bool use_sleeping_threads() const { return useSleepingThreads; }
+  int min_split_depth() const { return minimumSplitDepth; }
+  int size() const { return activeThreads; }
+
+  void set_size(int cnt);
+  void read_uci_options();
+  bool available_slave_exists(int master) const;
+
+  void getline(std::string& cmd);
+  void start_listener();
+  void stop_listener();
+  void set_timer(int msec);
+
+  template <bool Fake>
+  Value split(Position& pos, SearchStack* ss, Value alpha, Value beta, Value bestValue,
+              Depth depth, Move threatMove, int moveCount, MovePicker* mp, int nodeType);
+private:
+  friend struct Thread;
+
+  Thread threads[MAX_THREADS + 2]; // Last 2 are the listener and the timer
+  Lock threadsLock;
+  Depth minimumSplitDepth;
+  int maxThreadsPerSplitPoint;
+  int activeThreads;
+  bool useSleepingThreads;
+  WaitCondition sleepCond;
+  std::string inputLine;
 };
 
+extern ThreadsManager Threads;
+
 #endif // !defined(THREAD_H_INCLUDED)