unit: enqueue cgroup empty check event if the last ref on a unit is dropped

(cherry picked from commit e5c36295d81971ef75d9c6f98f0890b92a4a353f)

Resolves: #1697893

1 files changed, 6 insertions, 0 deletions

diff --git a/src/core/dbus-unit.c b/src/core/dbus-unit.c
index ae0410414e..c5bca10979 100644
--- a/src/core/dbus-unit.c
+++ b/src/core/dbus-unit.c
@@ -1746,7 +1746,13 @@ static int bus_unit_track_handler(sd_bus_track *t, void *userdata) {
 
         u->bus_track = sd_bus_track_unref(u->bus_track); /* make sure we aren't called again */
 
+        /* If the client that tracks us disappeared, then there's reason to believe that the cgroup is empty now too,
+         * let's see */
+        unit_add_to_cgroup_empty_queue(u);
+
+        /* Also add the unit to the GC queue, after all if the client left it might be time to GC this unit */
         unit_add_to_gc_queue(u);
+
         return 0;
 }