From 66a3d727cd8281911f9042cf9754e89b83bd3ce0 Mon Sep 17 00:00:00 2001
From: Robin Gareus <robin@gareus.org>
Date: Thu, 31 Mar 2022 21:50:27 +0200
Subject: [PATCH] Process rt-tasks (resample ports) in parallel (again).

This was changed to single-thread execution in
in bd229936ec2cb30fe3360f2d83ffc7197fd6fb97
and likely accidentally committed.
---
 libs/ardour/rt_tasklist.cc | 18 +++++++++++++-----
 1 file changed, 13 insertions(+), 5 deletions(-)

diff --git a/libs/ardour/rt_tasklist.cc b/libs/ardour/rt_tasklist.cc
index 18fcad8e3f..0b8841522f 100644
--- a/libs/ardour/rt_tasklist.cc
+++ b/libs/ardour/rt_tasklist.cc
@@ -144,29 +144,37 @@ void
 RTTaskList::process (TaskList const& tl)
 {
 	Glib::Threads::Mutex::Lock pm (_process_mutex);
+
+#ifndef NDEBUG
+	/* must not be called while processing is already running */
 	Glib::Threads::Mutex::Lock tm (_tasklist_mutex, Glib::Threads::NOT_LOCK);
-
 	tm.acquire ();
-	_tasklist = tl;
+	assert (_tasklist.empty ());
 	tm.release ();
+#endif
 
+	_tasklist = tl;
 	process_tasklist ();
 
+#ifndef NDEBUG
+	/* ensure that all tasks are processed, and threads are in wait state */
 	tm.acquire ();
-	_tasklist.clear ();
+	assert (_tasklist.empty ());
 	tm.release ();
+#endif
 }
 
 void
 RTTaskList::process_tasklist ()
 {
-//	if (0 == g_atomic_int_get (&_threads_active) || _threads.size () == 0) {
+	if (0 == g_atomic_int_get (&_threads_active) || _threads.size () == 0) {
 
 		for (TaskList::iterator i = _tasklist.begin (); i != _tasklist.end(); ++i) {
 			(*i)();
 		}
+		_tasklist.clear ();
 		return;
-//	}
+	}
 
 	uint32_t nt = std::min (_threads.size (), _tasklist.size ());