From: Marco Costalba <mcostalba@gmail.com>
Date: Sun, 19 Aug 2012 12:06:26 +0000 (+0100)
Subject: Avoid wake up master thread when useless
X-Git-Url: https://git.sesse.net/?p=stockfish;a=commitdiff_plain;h=2f4a9a140ae7882365f64ac11cf263bd505418e6;hp=dba1bc354a74bf7774c453ac779b3ce462c2b8e2

Avoid wake up master thread when useless

Check we are the last slave of the split point
before to wake up the master. This should avoid
spurious wakes up.

No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
---

diff --git a/src/search.cpp b/src/search.cpp
index 043ada63..a29fd0f6 100644
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -1728,8 +1728,11 @@ void Thread::idle_loop() {
           // case we are the last slave of the split point.
           if (    Threads.use_sleeping_threads()
               &&  this != sp->master
-              && !sp->master->is_searching)
+              && !sp->slavesMask)
+          {
+              assert(!sp->master->is_searching);
               sp->master->wake_up();
+          }
 
           // After releasing the lock we cannot access anymore any SplitPoint
           // related data in a safe way becuase it could have been released under