[Bf-blender-cvs] SVN commit: /data/svn/bf-blender [46534] trunk/blender/intern/cycles/util: Cycles: reviewed the task scheduler code and fixed (hopefully all) windows threading problems.

[Brecht Van Lommel]

Revision: 46534
          http://projects.blender.org/scm/viewvc.php?view=rev&root=bf-blender&revision=46534
Author:   blendix
Date:     2012-05-10 22:31:16 +0000 (Thu, 10 May 2012)
Log Message:
-----------
Cycles: reviewed the task scheduler code and fixed (hopefully all) windows threading problems.

Modified Paths:
--------------
    trunk/blender/intern/cycles/util/util_task.cpp
    trunk/blender/intern/cycles/util/util_task.h

Modified: trunk/blender/intern/cycles/util/util_task.cpp
===================================================================
--- trunk/blender/intern/cycles/util/util_task.cpp	2012-05-10 20:48:36 UTC (rev 46533)
+++ trunk/blender/intern/cycles/util/util_task.cpp	2012-05-10 22:31:16 UTC (rev 46534)
@@ -28,8 +28,6 @@
 TaskPool::TaskPool()
 {
 	num = 0;
-	num_done = 0;
-
 	do_cancel = false;
 }
 
@@ -55,9 +53,11 @@
 
 void TaskPool::wait_work()
 {
-	thread_scoped_lock done_lock(done_mutex);
+	thread_scoped_lock num_lock(num_mutex);
 
-	while(num_done != num) {
+	while(num != 0) {
+		num_lock.unlock();
+
 		thread_scoped_lock queue_lock(TaskScheduler::queue_mutex);
 
 		/* find task from this pool. if we get a task from another pool,
@@ -81,8 +81,6 @@
 
 		/* if found task, do it, otherwise wait until other tasks are done */
 		if(found_entry) {
-			done_lock.unlock();
-
 			/* run task */
 			work_entry.task->run();
 
@@ -90,26 +88,31 @@
 			delete work_entry.task;
 
 			/* notify pool task was done */
-			done_increase(1);
+			num_decrease(1);
+		}
 
-			done_lock.lock();
-		}
-		else
-			done_cond.wait(done_lock);
+		num_lock.lock();
+		if(num == 0)
+			break;
+
+		if(!found_entry)
+			num_cond.wait(num_lock);
 	}
 }
 
 void TaskPool::cancel()
 {
+	do_cancel = true;
+
 	TaskScheduler::clear(this);
-
-	do_cancel = true;
+	
 	{
-		thread_scoped_lock lock(done_mutex);
+		thread_scoped_lock num_lock(num_mutex);
 
-		while(num_done != num)
-			done_cond.wait(lock);
+		while(num)
+			num_cond.wait(num_lock);
 	}
+
 	do_cancel = false;
 }
 
@@ -117,7 +120,7 @@
 {
 	TaskScheduler::clear(this);
 
-	assert(num_done == num);
+	assert(num == 0);
 }
 
 bool TaskPool::cancelled()
@@ -125,16 +128,25 @@
 	return do_cancel;
 }
 
-void TaskPool::done_increase(int done)
+void TaskPool::num_decrease(int done)
 {
-	done_mutex.lock();
-	num_done += done;
-	done_mutex.unlock();
+	num_mutex.lock();
+	num -= done;
 
-	assert(num_done <= num);
-	done_cond.notify_all();
+	assert(num >= 0);
+	if(num == 0)
+		num_cond.notify_all();
+
+	num_mutex.unlock();
 }
 
+void TaskPool::num_increase()
+{
+	thread_scoped_lock num_lock(num_mutex);
+	num++;
+	num_cond.notify_all();
+}
+
 /* Task Scheduler */
 
 thread_mutex TaskScheduler::mutex;
@@ -196,10 +208,10 @@
 
 bool TaskScheduler::thread_wait_pop(Entry& entry)
 {
-	thread_scoped_lock lock(queue_mutex);
+	thread_scoped_lock queue_lock(queue_mutex);
 
 	while(queue.empty() && !do_exit)
-		queue_cond.wait(lock);
+		queue_cond.wait(queue_lock);
 
 	if(queue.empty()) {
 		assert(do_exit);
@@ -227,27 +239,28 @@
 		delete entry.task;
 
 		/* notify pool task was done */
-		entry.pool->done_increase(1);
+		entry.pool->num_decrease(1);
 	}
 }
 
 void TaskScheduler::push(Entry& entry, bool front)
 {
+	entry.pool->num_increase();
+
 	/* add entry to queue */
 	TaskScheduler::queue_mutex.lock();
 	if(front)
 		TaskScheduler::queue.push_front(entry);
 	else
 		TaskScheduler::queue.push_back(entry);
-	entry.pool->num++;
-	TaskScheduler::queue_mutex.unlock();
 
 	TaskScheduler::queue_cond.notify_one();
+	TaskScheduler::queue_mutex.unlock();
 }
 
 void TaskScheduler::clear(TaskPool *pool)
 {
-	thread_scoped_lock lock(queue_mutex);
+	thread_scoped_lock queue_lock(TaskScheduler::queue_mutex);
 
 	/* erase all tasks from this pool from the queue */
 	list<Entry>::iterator it = queue.begin();
@@ -266,8 +279,10 @@
 			it++;
 	}
 
+	queue_lock.unlock();
+
 	/* notify done */
-	pool->done_increase(done);
+	pool->num_decrease(done);
 }
 
 CCL_NAMESPACE_END

Modified: trunk/blender/intern/cycles/util/util_task.h
===================================================================
--- trunk/blender/intern/cycles/util/util_task.h	2012-05-10 20:48:36 UTC (rev 46533)
+++ trunk/blender/intern/cycles/util/util_task.h	2012-05-10 22:31:16 UTC (rev 46534)
@@ -73,12 +73,13 @@
 protected:
 	friend class TaskScheduler;
 
-	void done_increase(int done);
+	void num_decrease(int done);
+	void num_increase();
 
-	thread_mutex done_mutex;
-	thread_condition_variable done_cond;
+	thread_mutex num_mutex;
+	thread_condition_variable num_cond;
 
-	volatile int num, num_done;
+	volatile int num;
 	volatile bool do_cancel;
 };