From 9b8d82009278cc275a71102914bcb34850ce03b8 Mon Sep 17 00:00:00 2001
From: Venky Shankar <vshankar@redhat.com>
Date: Thu, 5 Aug 2021 04:35:10 -0400
Subject: [PATCH] cephfs-mirror: shutdown ClusterWatcher on termination

Fixes: https://tracker.ceph.com/issues/52062
Signed-off-by: Venky Shankar <vshankar@redhat.com>
---
 src/tools/cephfs_mirror/ClusterWatcher.cc | 10 +++++++++-
 src/tools/cephfs_mirror/ClusterWatcher.h  |  1 +
 src/tools/cephfs_mirror/Mirror.cc         |  2 +-
 3 files changed, 11 insertions(+), 2 deletions(-)

diff --git a/src/tools/cephfs_mirror/ClusterWatcher.cc b/src/tools/cephfs_mirror/ClusterWatcher.cc
index a5d04717a97..40aab756ee9 100644
--- a/src/tools/cephfs_mirror/ClusterWatcher.cc
+++ b/src/tools/cephfs_mirror/ClusterWatcher.cc
@@ -68,6 +68,7 @@ int ClusterWatcher::init() {
 void ClusterWatcher::shutdown() {
   dout(20) << dendl;
   std::scoped_lock locker(m_lock);
+  m_stopping = true;
   m_monc->sub_unwant("fsmap");
 }
 
@@ -84,6 +85,10 @@ void ClusterWatcher::handle_fsmap(const cref_t<MFSMap> &m) {
   std::map<Filesystem, uint64_t> fs_metadata_pools;
   {
     std::scoped_lock locker(m_lock);
+    if (m_stopping) {
+      return;
+    }
+
     // deleted filesystems are considered mirroring disabled
     for (auto it = m_filesystem_peers.begin(); it != m_filesystem_peers.end();) {
       if (!fsmap.filesystem_exists(it->first.fscid)) {
@@ -167,7 +172,10 @@ void ClusterWatcher::handle_fsmap(const cref_t<MFSMap> &m) {
     }
   }
 
-  m_monc->sub_got("fsmap", fsmap.get_epoch());
+  std::scoped_lock(m_lock);
+  if (!m_stopping) {
+    m_monc->sub_got("fsmap", fsmap.get_epoch());
+  } // else we have already done a sub_unwant()
 }
 
 } // namespace mirror
diff --git a/src/tools/cephfs_mirror/ClusterWatcher.h b/src/tools/cephfs_mirror/ClusterWatcher.h
index e3bf6298b50..a418898f555 100644
--- a/src/tools/cephfs_mirror/ClusterWatcher.h
+++ b/src/tools/cephfs_mirror/ClusterWatcher.h
@@ -65,6 +65,7 @@ private:
   ServiceDaemon *m_service_daemon;
   Listener &m_listener;
 
+  bool m_stopping = false;
   std::map<Filesystem, Peers> m_filesystem_peers;
 
   void handle_fsmap(const cref_t<MFSMap> &m);
diff --git a/src/tools/cephfs_mirror/Mirror.cc b/src/tools/cephfs_mirror/Mirror.cc
index efaa27106e5..88648f2b3a1 100644
--- a/src/tools/cephfs_mirror/Mirror.cc
+++ b/src/tools/cephfs_mirror/Mirror.cc
@@ -222,7 +222,6 @@ Mirror::~Mirror() {
   {
     std::scoped_lock locker(m_lock);
     m_thread_pool->stop();
-    m_cluster_watcher.reset();
   }
 }
 
@@ -285,6 +284,7 @@ int Mirror::init(std::string &reason) {
 void Mirror::shutdown() {
   dout(20) << dendl;
   m_stopping = true;
+  m_cluster_watcher->shutdown();
   m_cond.notify_all();
 }
 
-- 
2.39.5