From: Marco Costalba <mcostalba@gmail.com>
Date: Mon, 14 Jan 2013 18:32:30 +0000 (+0100)
Subject: Fix a bug in timer loop
X-Git-Url: https://git.sesse.net/?p=stockfish;a=commitdiff_plain;h=78a953177397f3eb85cfee4398975e8519895e6b;hp=d1143794a01cd0540cf47e3415815cd60cde9422

Fix a bug in timer loop

Silly logic bug introduced in dda7de17e74d7e8

Timer thread, when msec = 0, instead of going
to sleep, calls check_time() in an endless loop.

Spotted and reported by snino64 due to abnormally
high CPU usage.

No functional change.
---

diff --git a/src/thread.cpp b/src/thread.cpp
index bc0b3fcc..5f3b4d31 100644
--- a/src/thread.cpp
+++ b/src/thread.cpp
@@ -76,9 +76,10 @@ void TimerThread::idle_loop() {
   while (!do_exit)
   {
       mutex.lock();
-      while (!msec && !do_exit)
-          sleepCondition.wait_for(mutex, msec ? msec : INT_MAX);
+      do sleepCondition.wait_for(mutex, msec ? msec : INT_MAX);
+      while (!msec && !do_exit); // Don't allow wakeups when msec = 0
       mutex.unlock();
+
       check_time();
   }
 }