From 7e1b53480ef9a3f0a495c7af434d2df9b2a19ca6 Mon Sep 17 00:00:00 2001
From: Max Kellermann <max@musicpd.org>
Date: Wed, 14 Dec 2016 08:41:22 +0100
Subject: [PATCH] output/MultipleOutputs: parallelize EnableDisable()

---
 src/output/Internal.hxx        | 16 ++++++++--------
 src/output/MultipleOutputs.cxx |  9 ++++++++-
 src/output/OutputControl.cxx   |  8 ++++----
 3 files changed, 20 insertions(+), 13 deletions(-)

diff --git a/src/output/Internal.hxx b/src/output/Internal.hxx
index 6f45a44e7..bb8511f10 100644
--- a/src/output/Internal.hxx
+++ b/src/output/Internal.hxx
@@ -323,34 +323,34 @@ public:
 	void LockCommandWait(Command cmd);
 
 	/**
-	 * Enables the device.
+	 * Enables the device, but don't wait for completion.
 	 *
 	 * Caller must lock the mutex.
 	 */
-	void EnableWait();
+	void EnableAsync();
 
 	/**
-	 * Disables the device.
+	 * Disables the device, but don't wait for completion.
 	 *
 	 * Caller must lock the mutex.
 	 */
-	void DisableWait();
+	void DisableAsync();
 
 	/**
 	 * Attempt to enable or disable the device as specified by the
 	 * #enabled attribute; attempt to sync it with #really_enabled
-	 * (wrapper for EnableWait() or DisableWait()).
+	 * (wrapper for EnableAsync() or DisableAsync()).
 	 *
 	 * Caller must lock the mutex.
 	 */
-	void EnableDisableWait() {
+	void EnableDisableAsync() {
 		if (enabled == really_enabled)
 			return;
 
 		if (enabled)
-			EnableWait();
+			EnableAsync();
 		else
-			DisableWait();
+			DisableAsync();
 	}
 
 	void LockPauseAsync();
diff --git a/src/output/MultipleOutputs.cxx b/src/output/MultipleOutputs.cxx
index 6f846faaa..639aa1560 100644
--- a/src/output/MultipleOutputs.cxx
+++ b/src/output/MultipleOutputs.cxx
@@ -107,9 +107,16 @@ MultipleOutputs::FindByName(const char *name) const
 void
 MultipleOutputs::EnableDisable()
 {
+	/* parallel execution */
+
 	for (auto ao : outputs) {
 		const ScopeLock lock(ao->mutex);
-		ao->EnableDisableWait();
+		ao->EnableDisableAsync();
+	}
+
+	for (auto ao : outputs) {
+		const ScopeLock lock(ao->mutex);
+		ao->WaitForCommand();
 	}
 }
 
diff --git a/src/output/OutputControl.cxx b/src/output/OutputControl.cxx
index 01bca7ae8..f2c635fba 100644
--- a/src/output/OutputControl.cxx
+++ b/src/output/OutputControl.cxx
@@ -70,7 +70,7 @@ AudioOutput::LockCommandWait(Command cmd)
 }
 
 void
-AudioOutput::EnableWait()
+AudioOutput::EnableAsync()
 {
 	if (!thread.IsDefined()) {
 		if (plugin.enable == nullptr) {
@@ -84,11 +84,11 @@ AudioOutput::EnableWait()
 		StartThread();
 	}
 
-	CommandWait(Command::ENABLE);
+	CommandAsync(Command::ENABLE);
 }
 
 void
-AudioOutput::DisableWait()
+AudioOutput::DisableAsync()
 {
 	if (!thread.IsDefined()) {
 		if (plugin.disable == nullptr)
@@ -101,7 +101,7 @@ AudioOutput::DisableWait()
 		return;
 	}
 
-	CommandWait(Command::DISABLE);
+	CommandAsync(Command::DISABLE);
 }
 
 inline bool