Do not wait for threads falling asleep

[stockfish] / src / search.cpp

diff --git a/src/search.cpp b/src/search.cpp
index 38bd98e09dfd011083acf9735b5452775d34e659..2e3f9d5663718ad4cac483c1d46b630cc5888d36 100644 (file)
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -442,9 +442,6 @@ bool think(const Position& pos, bool infinite, bool ponder, int side_to_move,
   // Wake up sleeping threads
   TM.wake_sleeping_threads();
 
-  for (int i = 1; i < TM.active_threads(); i++)
-      assert(TM.thread_is_available(i, 0));
-
   // Set thinking time
   int myTime = time[side_to_move];
   int myIncrement = increment[side_to_move];
@@ -2586,35 +2583,38 @@ namespace {
     {
         // Slave threads can exit as soon as AllThreadsShouldExit raises,
         // master should exit as last one.
-        if (AllThreadsShouldExit && !waitSp)
+        if (AllThreadsShouldExit)
         {
+            assert(!waitSp);
             threads[threadID].state = THREAD_TERMINATED;
             return;
         }
 
         // If we are not thinking, wait for a condition to be signaled
         // instead of wasting CPU time polling for work.
-        while (    threadID != 0
-               && !AllThreadsShouldExit
-               && (AllThreadsShouldSleep || threadID >= ActiveThreads))
+        while (AllThreadsShouldSleep || threadID >= ActiveThreads)
         {
+            assert(threadID != 0);
             threads[threadID].state = THREAD_SLEEPING;
 
 #if !defined(_MSC_VER)
             pthread_mutex_lock(&WaitLock);
-            pthread_cond_wait(&WaitCond, &WaitLock);
+            if (AllThreadsShouldSleep || threadID >= ActiveThreads)
+                pthread_cond_wait(&WaitCond, &WaitLock);
             pthread_mutex_unlock(&WaitLock);
 #else
             WaitForSingleObject(SitIdleEvent[threadID], INFINITE);
 #endif
-            // State is already changed by wake_sleeping_threads()
-            assert(threads[threadID].state == THREAD_AVAILABLE || threadID >= ActiveThreads);
         }
 
+        // If thread has just woken up, mark it as available
+        if (threads[threadID].state == THREAD_SLEEPING)
+            threads[threadID].state = THREAD_AVAILABLE;
+
         // If this thread has been assigned work, launch a search
         if (threads[threadID].state == THREAD_WORKISWAITING)
         {
-            assert(!AllThreadsShouldExit);
+            assert(!AllThreadsShouldExit && !AllThreadsShouldSleep);
 
             threads[threadID].state = THREAD_SEARCHING;
 
@@ -2820,7 +2820,9 @@ namespace {
     assert(p.is_ok());
     assert(sstck != NULL);
     assert(ply >= 0 && ply < PLY_MAX);
-    assert(*bestValue >= -VALUE_INFINITE && *bestValue <= *alpha);
+    assert(*bestValue >= -VALUE_INFINITE);
+    assert(   ( pvNode && *bestValue <= *alpha)
+           || (!pvNode && *bestValue <   beta ));
     assert(!pvNode || *alpha < beta);
     assert(beta <= VALUE_INFINITE);
     assert(depth > Depth(0));
@@ -2933,12 +2935,8 @@ namespace {
         return;
 
     for (int i = 1; i < ActiveThreads; i++)
-    {
         assert(threads[i].state == THREAD_SLEEPING);
 
-        threads[i].state = THREAD_AVAILABLE;
-    }
-
 #if !defined(_MSC_VER)
     pthread_mutex_lock(&WaitLock);
     pthread_cond_broadcast(&WaitCond);
@@ -2962,12 +2960,9 @@ namespace {
     // This makes the threads to go to sleep
     AllThreadsShouldSleep = true;
 
-    // Wait for the threads to be all sleeping and reset flags
-    // to a known state.
+    // Reset flags to a known state.
     for (int i = 1; i < ActiveThreads; i++)
     {
-        while (threads[i].state != THREAD_SLEEPING);
-
         // This flag can be in a random state
         threads[i].printCurrentLineRequest = false;
     }