Move idle_loop() under Thread

[stockfish] / src / search.cpp

diff --git a/src/search.cpp b/src/search.cpp
index c4e354e4b73d6bf15de78d610aadec8fb17e9fc2..49074cee9c20d6a1bb9ff733394c7a966115d42e 100644 (file)
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -2130,50 +2130,56 @@ split_point_start: // At split points actual search starts from here
 } // namespace
 
 
 } // namespace
 
 

-// ThreadsManager::idle_loop() is where the threads are parked when they have no work
-// to do. The parameter 'sp', if non-NULL, is a pointer to an active SplitPoint
-// object for which the current thread is the master.
+// Little helper used by idle_loop() to check that all the slaves of a
+// master thread have finished searching.

 
 

-void ThreadsManager::idle_loop(int threadID, SplitPoint* sp) {
+static bool all_slaves_finished(SplitPoint* sp) {

 
 

-  assert(threadID >= 0 && threadID < MAX_THREADS);
+  assert(sp);
+
+  for (int i = 0; i < Threads.size(); i++)
+      if (sp->is_slave[i])
+          return false;
+
+  return true;
+}

 
 

-  int i;
-  bool allFinished;
+
+// Thread::idle_loop() is where the thread is parked when it has no work to do.
+// The parameter 'sp', if non-NULL, is a pointer to an active SplitPoint object
+// for which the thread is the master.
+
+void Thread::idle_loop(SplitPoint* sp) {

 
   while (true)
   {
 
   while (true)
   {

-      // Slave threads can exit as soon as allThreadsShouldExit flag raises,
-      // master should exit as last one.
-      if (allThreadsShouldExit)
-      {
-          assert(!sp);
-          threads[threadID].state = Thread::TERMINATED;
-          return;
-      }
-

       // If we are not searching, wait for a condition to be signaled
       // instead of wasting CPU time polling for work.
       // If we are not searching, wait for a condition to be signaled
       // instead of wasting CPU time polling for work.

-      while (   threadID >= activeThreads
-             || threads[threadID].state == Thread::INITIALIZING
-             || (useSleepingThreads && threads[threadID].state == Thread::AVAILABLE))
+      while (   do_sleep
+             || do_terminate
+             || (Threads.use_sleeping_threads() && state == Thread::AVAILABLE))

       {
       {

-          assert(!sp || useSleepingThreads);
-          assert(threadID != 0 || useSleepingThreads);
+          assert(!sp || Threads.use_sleeping_threads());
+          assert(threadID != 0 || Threads.use_sleeping_threads());

 
 

-          if (threads[threadID].state == Thread::INITIALIZING)
-              threads[threadID].state = Thread::AVAILABLE;
+          // Slave thread should exit as soon as do_terminate flag raises
+          if (do_terminate)
+          {
+              assert(!sp);
+              state = Thread::TERMINATED;
+              return;
+          }
+
+          if (state == Thread::INITIALIZING)
+              state = Thread::AVAILABLE;

 
           // Grab the lock to avoid races with Thread::wake_up()
 
           // Grab the lock to avoid races with Thread::wake_up()

-          lock_grab(&threads[threadID].sleepLock);
+          lock_grab(&sleepLock);

 
           // If we are master and all slaves have finished don't go to sleep
 
           // If we are master and all slaves have finished don't go to sleep

-          for (i = 0; sp && i < activeThreads && !sp->is_slave[i]; i++) {}
-          allFinished = (i == activeThreads);
-
-          if (allFinished || allThreadsShouldExit)
+          if (sp && all_slaves_finished(sp))

           {
           {

-              lock_release(&threads[threadID].sleepLock);
+              lock_release(&sleepLock);

               break;
           }
 
               break;
           }
 


@@ -2181,22 +2187,22 @@ void ThreadsManager::idle_loop(int threadID, SplitPoint* sp) {
           // particular we need to avoid a deadlock in case a master thread has,
           // in the meanwhile, allocated us and sent the wake_up() call before we
           // had the chance to grab the lock.
           // particular we need to avoid a deadlock in case a master thread has,
           // in the meanwhile, allocated us and sent the wake_up() call before we
           // had the chance to grab the lock.

-          if (threadID >= activeThreads || threads[threadID].state == Thread::AVAILABLE)
-              cond_wait(&threads[threadID].sleepCond, &threads[threadID].sleepLock);
+          if (do_sleep || state == Thread::AVAILABLE)
+              cond_wait(&sleepCond, &sleepLock);

 
 

-          lock_release(&threads[threadID].sleepLock);
+          lock_release(&sleepLock);

       }
 
       // If this thread has been assigned work, launch a search
       }
 
       // If this thread has been assigned work, launch a search

-      if (threads[threadID].state == Thread::WORKISWAITING)
+      if (state == Thread::WORKISWAITING)

       {
       {

-          assert(!allThreadsShouldExit);
+          assert(!do_terminate);

 
 

-          threads[threadID].state = Thread::SEARCHING;
+          state = Thread::SEARCHING;

 
           // Copy split point position and search stack and call search()
           SearchStack ss[PLY_MAX_PLUS_2];
 
           // Copy split point position and search stack and call search()
           SearchStack ss[PLY_MAX_PLUS_2];

-          SplitPoint* tsp = threads[threadID].splitPoint;
+          SplitPoint* tsp = splitPoint;

           Position pos(*tsp->pos, threadID);
 
           memcpy(ss, tsp->ss - 1, 4 * sizeof(SearchStack));
           Position pos(*tsp->pos, threadID);
 
           memcpy(ss, tsp->ss - 1, 4 * sizeof(SearchStack));


@@ -2211,24 +2217,21 @@ void ThreadsManager::idle_loop(int threadID, SplitPoint* sp) {
           else
               assert(false);
 
           else
               assert(false);
 

-          assert(threads[threadID].state == Thread::SEARCHING);
+          assert(state == Thread::SEARCHING);

 
 

-          threads[threadID].state = Thread::AVAILABLE;
+          state = Thread::AVAILABLE;

 
           // Wake up master thread so to allow it to return from the idle loop in
           // case we are the last slave of the split point.
 
           // Wake up master thread so to allow it to return from the idle loop in
           // case we are the last slave of the split point.

-          if (   useSleepingThreads
+          if (   Threads.use_sleeping_threads()

               && threadID != tsp->master
               && threadID != tsp->master

-              && threads[tsp->master].state == Thread::AVAILABLE)
-              threads[tsp->master].wake_up();
+              && Threads[tsp->master].state == Thread::AVAILABLE)
+              Threads[tsp->master].wake_up();

       }
 
       // If this thread is the master of a split point and all slaves have
       // finished their work at this split point, return from the idle loop.
       }
 
       // If this thread is the master of a split point and all slaves have
       // finished their work at this split point, return from the idle loop.

-      for (i = 0; sp && i < activeThreads && !sp->is_slave[i]; i++) {}
-      allFinished = (i == activeThreads);
-
-      if (allFinished)
+      if (sp && all_slaves_finished(sp))

       {
           // Because sp->is_slave[] is reset under lock protection,
           // be sure sp->lock has been released before to return.
       {
           // Because sp->is_slave[] is reset under lock protection,
           // be sure sp->lock has been released before to return.