From 59e186d208e500f469791c66798337d6c00df08b Mon Sep 17 00:00:00 2001
From: Johannes Lorenz <1042576+JohannesLorenz@users.noreply.github.com>
Date: Thu, 11 Jul 2019 18:22:41 +0200
Subject: [PATCH] Closes #5050: Add Mixer threading comments (#5069)

[ci skip]
---
 include/Mixer.h    | 3 +++
 src/core/Mixer.cpp | 2 ++
 2 files changed, 5 insertions(+)

diff --git a/include/Mixer.h b/include/Mixer.h
index cea592905..69ea0d12d 100644
--- a/include/Mixer.h
+++ b/include/Mixer.h
@@ -315,6 +315,7 @@ public:
 	inline bool isMetronomeActive() const { return m_metronomeActive; }
 	inline void setMetronomeActive(bool value = true) { m_metronomeActive = value; }
 
+	//! Block until a change in model can be done (i.e. wait for audio thread)
 	void requestChangeInModel();
 	void doneChangeInModel();
 
@@ -366,6 +367,8 @@ private:
 
 	void clearInternal();
 
+	//! Called by the audio thread to give control to other threads,
+	//! such that they can do changes in the model (like e.g. removing effects)
 	void runChangesInModel();
 
 	bool m_renderOnly;
diff --git a/src/core/Mixer.cpp b/src/core/Mixer.cpp
index 7e41f2097..2550b072e 100644
--- a/src/core/Mixer.cpp
+++ b/src/core/Mixer.cpp
@@ -831,7 +831,9 @@ void Mixer::runChangesInModel()
 	if( m_changesSignal )
 	{
 		m_waitChangesMutex.lock();
+		// allow changes in the model from other threads ...
 		m_changesRequestCondition.wakeOne();
+		// ... and wait until they are done
 		m_changesMixerCondition.wait( &m_waitChangesMutex );
 		m_waitChangesMutex.unlock();
 	}