From: Francis Deslauriers <francis.deslauriers@efficios.com>
Date: Mon, 14 Dec 2020 22:30:12 +0000 (-0500)
Subject: Fix: add rcu_barrier() after sessiond_cleanup()
X-Git-Tag: v2.13.0-rc1~373
X-Git-Url: http://git.lttng.org/?p=lttng-tools.git;a=commitdiff_plain;h=3b8a092fd73f011309058e0ca15c00ced3664803

Fix: add rcu_barrier() after sessiond_cleanup()

This is to ensure that tracer event source (event notifier socket) are
removed from the notification thread list.

Signed-off-by: Francis Deslauriers <francis.deslauriers@efficios.com>
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>
Change-Id: I2ca8f72c023132c341193bf626c0dac20b89e1f2
---

diff --git a/src/bin/lttng-sessiond/main.c b/src/bin/lttng-sessiond/main.c
index 4bdac5217..9cc15d720 100644
--- a/src/bin/lttng-sessiond/main.c
+++ b/src/bin/lttng-sessiond/main.c
@@ -1779,6 +1779,13 @@ stop_threads:
 	rcu_thread_online();
 	sessiond_cleanup();
 
+	/*
+	 * Wait for all pending call_rcu work to complete tearing shutting down
+	 * the notification thread. This call_rcu work includes shutting down
+	 * UST apps and event notifier pipes.
+	 */
+	rcu_barrier();
+
 	if (notification_thread) {
 		lttng_thread_shutdown(notification_thread);
 		lttng_thread_put(notification_thread);