From d5bfbe1cf4cbaff864175209488589314eb85411 Mon Sep 17 00:00:00 2001
From: Paul Davis <paul@linuxaudiosystems.com>
Date: Fri, 1 Jan 2021 18:28:26 -0700
Subject: [PATCH] libtemporal: provide API to abort TempoMap RCU update step

---
 libs/temporal/tempo.cc | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/libs/temporal/tempo.cc b/libs/temporal/tempo.cc
index 713cc14343..5d4ee9e616 100644
--- a/libs/temporal/tempo.cc
+++ b/libs/temporal/tempo.cc
@@ -2952,3 +2952,16 @@ TempoMap::update (TempoMap::SharedPtr m)
 
 	MapChanged (); /* EMIT SIGNAL */
 }
+
+void
+TempoMap::abort_update ()
+{
+	/* drop lock taken by write_copy() */
+	_map_mgr.abort ();
+	/* update thread local map pointer in calling thread. Note that this
+	   will reset _tempo_map_p, which is (almost guaranteed to be) the only
+	   reference to the copy of the map made in ::write_copy(), so it will
+	   be destroyed here.
+	*/
+	TempoMap::fetch ();
+}