From f0f0fd2b75436b3e76d237b3eb26c684bc79c5c8 Mon Sep 17 00:00:00 2001
From: Peter Thoman <peter@metaclassofnil.com>
Date: Wed, 1 May 2013 13:20:25 +0200
Subject: [PATCH] Forgot loop sequentialization

---
 thread/threadpool.cpp | 2 ++
 thread/threadpool.h   | 4 ++--
 2 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/thread/threadpool.cpp b/thread/threadpool.cpp
index 86794c6faa..cc596a6ab5 100644
--- a/thread/threadpool.cpp
+++ b/thread/threadpool.cpp
@@ -55,6 +55,7 @@ void ThreadPool::StartWorkers() {
 }
 
 void ThreadPool::ParallelLoop(std::function<void(int,int)> loop, int lower, int upper) {
+	mutex.lock();
 	StartWorkers();
 	int range = upper-lower;
 	if(range >= numThreads*2) { // don't parallelize tiny loops
@@ -70,5 +71,6 @@ void ThreadPool::ParallelLoop(std::function<void(int,int)> loop, int lower, int
 	} else {
 		loop(lower, upper);
 	}
+	mutex.unlock();
 }
 
diff --git a/thread/threadpool.h b/thread/threadpool.h
index 19b563c9d7..6f90073d8c 100644
--- a/thread/threadpool.h
+++ b/thread/threadpool.h
@@ -34,8 +34,8 @@ private:
 };
 
 // A thread pool manages a set of worker threads, and allows the execution of parallel loops on them
-// individual parallel loops are sequentialized, which should not be a problem as they should each
-// use the entire system
+// individual parallel loops are fully sequentialized to simplify synchronization, which should not 
+// be a problem as they should each use the entire system
 class ThreadPool {
 public:
 	ThreadPool(int numThreads);