From 2ea7c6c4fd86eae8e7aa95576824938d913242ca Mon Sep 17 00:00:00 2001
From: Lukas W <lukaswhl@gmail.com>
Date: Sun, 29 Apr 2018 17:01:51 +0200
Subject: [PATCH 1/2] Fix job queue crash

* Don't add jobs when job queue is full
* Icrease job queue size from 1024 to 8192
---
 include/MixerWorkerThread.h    |  2 +-
 src/core/MixerWorkerThread.cpp | 11 +++++++++--
 2 files changed, 10 insertions(+), 3 deletions(-)

diff --git a/include/MixerWorkerThread.h b/include/MixerWorkerThread.h
index 8b900195f4f..4af42897cb2 100644
--- a/include/MixerWorkerThread.h
+++ b/include/MixerWorkerThread.h
@@ -62,7 +62,7 @@ class MixerWorkerThread : public QThread
 		void wait();
 
 	private:
-#define JOB_QUEUE_SIZE 1024
+#define JOB_QUEUE_SIZE 8192
 		QAtomicPointer<ThreadableJob> m_items[JOB_QUEUE_SIZE];
 		AtomicInt m_queueSize;
 		AtomicInt m_itemsDone;
diff --git a/src/core/MixerWorkerThread.cpp b/src/core/MixerWorkerThread.cpp
index e8c6bd61c08..14363f4d125 100644
--- a/src/core/MixerWorkerThread.cpp
+++ b/src/core/MixerWorkerThread.cpp
@@ -25,6 +25,7 @@
 #include "MixerWorkerThread.h"
 
 #include "denormals.h"
+#include <QDebug>
 #include <QMutex>
 #include <QWaitCondition>
 #include "ThreadableJob.h"
@@ -54,7 +55,13 @@ void MixerWorkerThread::JobQueue::addJob( ThreadableJob * _job )
 		// update job state
 		_job->queue();
 		// actually queue the job via atomic operations
-		m_items[m_queueSize.fetchAndAddOrdered(1)] = _job;
+		auto index = m_queueSize.fetchAndAddOrdered(1);
+		if (index < JOB_QUEUE_SIZE) {
+			m_items[index] = _job;
+		} else {
+			qWarning() << "Job queue is full!";
+			m_itemsDone.fetchAndAddOrdered(1);
+		}
 	}
 }
 
@@ -66,7 +73,7 @@ void MixerWorkerThread::JobQueue::run()
 	while( processedJob && (int) m_itemsDone < (int) m_queueSize )
 	{
 		processedJob = false;
-		for( int i = 0; i < m_queueSize; ++i )
+		for( int i = 0; i < m_queueSize && i < JOB_QUEUE_SIZE; ++i )
 		{
 			ThreadableJob * job = m_items[i].fetchAndStoreOrdered( NULL );
 			if( job )

From bd608ed353a2a00da06b40052e3432ef4176fff2 Mon Sep 17 00:00:00 2001
From: Lukas W <lukaswhl@gmail.com>
Date: Wed, 2 May 2018 12:54:45 +0200
Subject: [PATCH 2/2] JobQueue: Rename m_queueSize to m_writeIndex

Hopefully makes it less confusing that m_writeIndex grows beyond
JOB_QUEUE_SIZE when the queue is full.
---
 include/MixerWorkerThread.h    |  4 ++--
 src/core/MixerWorkerThread.cpp | 10 +++++-----
 2 files changed, 7 insertions(+), 7 deletions(-)

diff --git a/include/MixerWorkerThread.h b/include/MixerWorkerThread.h
index 4af42897cb2..8d6b0c72a26 100644
--- a/include/MixerWorkerThread.h
+++ b/include/MixerWorkerThread.h
@@ -48,7 +48,7 @@ class MixerWorkerThread : public QThread
 
 		JobQueue() :
 			m_items(),
-			m_queueSize( 0 ),
+			m_writeIndex( 0 ),
 			m_itemsDone( 0 ),
 			m_opMode( Static )
 		{
@@ -64,7 +64,7 @@ class MixerWorkerThread : public QThread
 	private:
 #define JOB_QUEUE_SIZE 8192
 		QAtomicPointer<ThreadableJob> m_items[JOB_QUEUE_SIZE];
-		AtomicInt m_queueSize;
+		AtomicInt m_writeIndex;
 		AtomicInt m_itemsDone;
 		OperationMode m_opMode;
 
diff --git a/src/core/MixerWorkerThread.cpp b/src/core/MixerWorkerThread.cpp
index 14363f4d125..ae5d505647b 100644
--- a/src/core/MixerWorkerThread.cpp
+++ b/src/core/MixerWorkerThread.cpp
@@ -40,7 +40,7 @@ QList<MixerWorkerThread *> MixerWorkerThread::workerThreads;
 // implementation of internal JobQueue
 void MixerWorkerThread::JobQueue::reset( OperationMode _opMode )
 {
-	m_queueSize = 0;
+	m_writeIndex = 0;
 	m_itemsDone = 0;
 	m_opMode = _opMode;
 }
@@ -55,7 +55,7 @@ void MixerWorkerThread::JobQueue::addJob( ThreadableJob * _job )
 		// update job state
 		_job->queue();
 		// actually queue the job via atomic operations
-		auto index = m_queueSize.fetchAndAddOrdered(1);
+		auto index = m_writeIndex.fetchAndAddOrdered(1);
 		if (index < JOB_QUEUE_SIZE) {
 			m_items[index] = _job;
 		} else {
@@ -70,10 +70,10 @@ void MixerWorkerThread::JobQueue::addJob( ThreadableJob * _job )
 void MixerWorkerThread::JobQueue::run()
 {
 	bool processedJob = true;
-	while( processedJob && (int) m_itemsDone < (int) m_queueSize )
+	while( processedJob && (int) m_itemsDone < (int) m_writeIndex )
 	{
 		processedJob = false;
-		for( int i = 0; i < m_queueSize && i < JOB_QUEUE_SIZE; ++i )
+		for( int i = 0; i < m_writeIndex && i < JOB_QUEUE_SIZE; ++i )
 		{
 			ThreadableJob * job = m_items[i].fetchAndStoreOrdered( NULL );
 			if( job )
@@ -93,7 +93,7 @@ void MixerWorkerThread::JobQueue::run()
 
 void MixerWorkerThread::JobQueue::wait()
 {
-	while( (int) m_itemsDone < (int) m_queueSize )
+	while( (int) m_itemsDone < (int) m_writeIndex )
 	{
 #if defined(LMMS_HOST_X86) || defined(LMMS_HOST_X86_64)
 		asm( "pause" );