]> git.sesse.net Git - stockfish/blobdiff - src/search.cpp
Disable spinlocks
[stockfish] / src / search.cpp
index 18c520f15fd71aebec2becbe72463612b5d84df0..681acb8141a0e1b5d7c8def9569ce28e8bb15ffc 100644 (file)
@@ -41,7 +41,7 @@ namespace Search {
   LimitsType Limits;
   RootMoveVector RootMoves;
   Position RootPos;
-  Time::point SearchTime;
+  TimePoint SearchTime;
   StateStackPtr SetupStates;
 }
 
@@ -355,7 +355,7 @@ namespace {
                 // the UI) before a re-search.
                 if (   multiPV == 1
                     && (bestValue <= alpha || bestValue >= beta)
-                    && Time::now() - SearchTime > 3000)
+                    && now() - SearchTime > 3000)
                     sync_cout << UCI::pv(pos, depth, alpha, beta) << sync_endl;
 
                 // In case of failing low/high increase aspiration window and
@@ -386,9 +386,9 @@ namespace {
 
             if (Signals.stop)
                 sync_cout << "info nodes " << RootPos.nodes_searched()
-                          << " time " << Time::now() - SearchTime << sync_endl;
+                          << " time " << now() - SearchTime << sync_endl;
 
-            else if (PVIdx + 1 == multiPV || Time::now() - SearchTime > 3000)
+            else if (PVIdx + 1 == multiPV || now() - SearchTime > 3000)
                 sync_cout << UCI::pv(pos, depth, alpha, beta) << sync_endl;
         }
 
@@ -412,7 +412,7 @@ namespace {
             // Stop the search if only one legal move is available or all
             // of the available time has been used.
             if (   RootMoves.size() == 1
-                || Time::now() - SearchTime > TimeMgr.available_time())
+                || now() - SearchTime > TimeMgr.available_time())
             {
                 // If we are allowed to ponder do not stop the search now but
                 // keep pondering until the GUI sends "ponderhit" or "stop".
@@ -765,7 +765,7 @@ moves_loop: // When in check and at SpNode search starts from here
               continue;
 
           moveCount = ++splitPoint->moveCount;
-          splitPoint->mutex.unlock();
+          splitPoint->spinlock.release();
       }
       else
           ++moveCount;
@@ -774,7 +774,7 @@ moves_loop: // When in check and at SpNode search starts from here
       {
           Signals.firstRootMove = (moveCount == 1);
 
-          if (thisThread == Threads.main() && Time::now() - SearchTime > 3000)
+          if (thisThread == Threads.main() && now() - SearchTime > 3000)
               sync_cout << "info depth " << depth / ONE_PLY
                         << " currmove " << UCI::move(move, pos.is_chess960())
                         << " currmovenumber " << moveCount + PVIdx << sync_endl;
@@ -834,7 +834,7 @@ moves_loop: // When in check and at SpNode search starts from here
               && moveCount >= FutilityMoveCounts[improving][depth])
           {
               if (SpNode)
-                  splitPoint->mutex.lock();
+                  splitPoint->spinlock.acquire();
 
               continue;
           }
@@ -853,7 +853,7 @@ moves_loop: // When in check and at SpNode search starts from here
 
                   if (SpNode)
                   {
-                      splitPoint->mutex.lock();
+                      splitPoint->spinlock.acquire();
                       if (bestValue > splitPoint->bestValue)
                           splitPoint->bestValue = bestValue;
                   }
@@ -865,7 +865,7 @@ moves_loop: // When in check and at SpNode search starts from here
           if (predictedDepth < 4 * ONE_PLY && pos.see_sign(move) < VALUE_ZERO)
           {
               if (SpNode)
-                  splitPoint->mutex.lock();
+                  splitPoint->spinlock.acquire();
 
               continue;
           }
@@ -965,7 +965,7 @@ moves_loop: // When in check and at SpNode search starts from here
       // Step 18. Check for new best move
       if (SpNode)
       {
-          splitPoint->mutex.lock();
+          splitPoint->spinlock.acquire();
           bestValue = splitPoint->bestValue;
           alpha = splitPoint->alpha;
       }
@@ -1373,7 +1373,7 @@ moves_loop: // When in check and at SpNode search starts from here
   Move Skill::pick_best(size_t multiPV) {
 
     // PRNG sequence should be non-deterministic, so we seed it with the time at init
-    static PRNG rng(Time::now());
+    static PRNG rng(now());
 
     // RootMoves are already sorted by score in descending order
     int variance = std::min(RootMoves[0].score - RootMoves[multiPV - 1].score, PawnValueMg);
@@ -1407,7 +1407,7 @@ moves_loop: // When in check and at SpNode search starts from here
 string UCI::pv(const Position& pos, Depth depth, Value alpha, Value beta) {
 
   std::stringstream ss;
-  Time::point elapsed = Time::now() - SearchTime + 1;
+  TimePoint elapsed = now() - SearchTime + 1;
   size_t multiPV = std::min((size_t)Options["MultiPV"], RootMoves.size());
   int selDepth = 0;
 
@@ -1526,13 +1526,13 @@ void Thread::idle_loop() {
       // If this thread has been assigned work, launch a search
       while (searching)
       {
-          Threads.mutex.lock();
+          Threads.spinlock.acquire();
 
           assert(activeSplitPoint);
 
           SplitPoint* sp = activeSplitPoint;
 
-          Threads.mutex.unlock();
+          Threads.spinlock.release();
 
           Stack stack[MAX_PLY+4], *ss = stack+2; // To allow referencing (ss-2) and (ss+2)
           Position pos(*sp->pos, this);
@@ -1540,7 +1540,7 @@ void Thread::idle_loop() {
           std::memcpy(ss-2, sp->ss-2, 5 * sizeof(Stack));
           ss->splitPoint = sp;
 
-          sp->mutex.lock();
+          sp->spinlock.acquire();
 
           assert(activePosition == nullptr);
 
@@ -1578,12 +1578,12 @@ void Thread::idle_loop() {
           // After releasing the lock we can't access any SplitPoint related data
           // in a safe way because it could have been released under our feet by
           // the sp master.
-          sp->mutex.unlock();
+          sp->spinlock.release();
 
           // Try to late join to another split point if none of its slaves has
           // already finished.
           SplitPoint* bestSp = NULL;
-          int bestScore = INT_MAX;
+          int minLevel = INT_MAX;
 
           for (Thread* th : Threads)
           {
@@ -1593,7 +1593,7 @@ void Thread::idle_loop() {
               if (   sp
                   && sp->allSlavesSearching
                   && sp->slavesMask.count() < MAX_SLAVES_PER_SPLITPOINT
-                  && available_to(th))
+                  && can_join(sp))
               {
                   assert(this != th);
                   assert(!(this_sp && this_sp->slavesMask.none()));
@@ -1601,16 +1601,14 @@ void Thread::idle_loop() {
 
                   // Prefer to join to SP with few parents to reduce the probability
                   // that a cut-off occurs above us, and hence we waste our work.
-                  int level = -1;
-                  for (SplitPoint* spp = th->activeSplitPoint; spp; spp = spp->parentSplitPoint)
+                  int level = 0;
+                  for (SplitPoint* p = th->activeSplitPoint; p; p = p->parentSplitPoint)
                       level++;
 
-                  int score = level * 256 * 256 + (int)sp->slavesMask.count() * 256 - sp->depth * 1;
-
-                  if (score < bestScore)
+                  if (level < minLevel)
                   {
                       bestSp = sp;
-                      bestScore = score;
+                      minLevel = level;
                   }
               }
           }
@@ -1620,20 +1618,20 @@ void Thread::idle_loop() {
               sp = bestSp;
 
               // Recheck the conditions under lock protection
-              Threads.mutex.lock();
-              sp->mutex.lock();
+              Threads.spinlock.acquire();
+              sp->spinlock.acquire();
 
               if (   sp->allSlavesSearching
                   && sp->slavesMask.count() < MAX_SLAVES_PER_SPLITPOINT
-                  && available_to(sp->master))
+                  && can_join(sp))
               {
                   sp->slavesMask.set(idx);
                   activeSplitPoint = sp;
                   searching = true;
               }
 
-              sp->mutex.unlock();
-              Threads.mutex.unlock();
+              sp->spinlock.release();
+              Threads.spinlock.release();
           }
       }
 
@@ -1661,12 +1659,12 @@ void Thread::idle_loop() {
 
 void check_time() {
 
-  static Time::point lastInfoTime = Time::now();
-  Time::point elapsed = Time::now() - SearchTime;
+  static TimePoint lastInfoTime = now();
+  TimePoint elapsed = now() - SearchTime;
 
-  if (Time::now() - lastInfoTime >= 1000)
+  if (now() - lastInfoTime >= 1000)
   {
-      lastInfoTime = Time::now();
+      lastInfoTime = now();
       dbg_print();
   }
 
@@ -1689,7 +1687,7 @@ void check_time() {
 
   else if (Limits.nodes)
   {
-      Threads.mutex.lock();
+      Threads.spinlock.acquire();
 
       int64_t nodes = RootPos.nodes_searched();
 
@@ -1700,7 +1698,7 @@ void check_time() {
           {
               SplitPoint& sp = th->splitPoints[i];
 
-              sp.mutex.lock();
+              sp.spinlock.acquire();
 
               nodes += sp.nodes;
 
@@ -1708,10 +1706,10 @@ void check_time() {
                   if (sp.slavesMask.test(idx) && Threads[idx]->activePosition)
                       nodes += Threads[idx]->activePosition->nodes_searched();
 
-              sp.mutex.unlock();
+              sp.spinlock.release();
           }
 
-      Threads.mutex.unlock();
+      Threads.spinlock.release();
 
       if (nodes >= Limits.nodes)
           Signals.stop = true;