From 567b6dcd4ff8e4a9c9b0b1629fa8c015d5e6a724 Mon Sep 17 00:00:00 2001
From: Lennart Poettering <lennart@poettering.net>
Date: Mon, 2 Jan 2023 15:01:56 +0100
Subject: [PATCH] pid1: make sure we send our calling service manager
 RELOADING=1 when reloading

And send READY=1 again when we are done with it.

We do this not only for "daemon-reload" but also for "daemon-reexec" and
"switch-root", since from the perspective of an encapsulating service
manager these three operations are not that different.

(cherry picked from commit dd0ab174c36492cdcb92cf46844fb0905b1d4a7e)

Related: RHEL-6090
---
 src/core/main.c        | 10 ++++++++++
 src/core/manager.c     | 12 ++++++++++++
 src/core/manager.h     |  1 +
 units/user@.service.in |  2 +-
 4 files changed, 24 insertions(+), 1 deletion(-)

diff --git a/src/core/main.c b/src/core/main.c
index 0e2e5448bb..126a4bce8c 100644
--- a/src/core/main.c
+++ b/src/core/main.c
@@ -1925,6 +1925,8 @@ static int invoke_main_loop(
                         LogTarget saved_log_target;
                         int saved_log_level;
 
+                        manager_send_reloading(m);
+
                         log_info("Reloading.");
 
                         /* First, save any overridden log level/target, then parse the configuration file,
@@ -1955,6 +1957,10 @@ static int invoke_main_loop(
                 }
 
                 case MANAGER_REEXECUTE:
+
+                        manager_send_reloading(m); /* From the perspective of the manager calling us this is
+                                                    * pretty much the same as a reload */
+
                         r = prepare_reexecute(m, &arg_serialization, ret_fds, false);
                         if (r < 0) {
                                 *ret_error_message = "Failed to prepare for reexecution";
@@ -1970,6 +1976,10 @@ static int invoke_main_loop(
                         return objective;
 
                 case MANAGER_SWITCH_ROOT:
+
+                        manager_send_reloading(m); /* From the perspective of the manager calling us this is
+                                                    * pretty much the same as a reload */
+
                         manager_set_switching_root(m, true);
 
                         if (!m->switch_root_init) {
diff --git a/src/core/manager.c b/src/core/manager.c
index 6371810ce3..b34103d7d3 100644
--- a/src/core/manager.c
+++ b/src/core/manager.c
@@ -3641,6 +3641,18 @@ void manager_check_finished(Manager *m) {
         manager_invalidate_startup_units(m);
 }
 
+void manager_send_reloading(Manager *m) {
+        assert(m);
+
+        /* Let whoever invoked us know that we are now reloading */
+        (void) sd_notifyf(/* unset= */ false,
+                          "RELOADING=1\n"
+                          "MONOTONIC_USEC=" USEC_FMT "\n", now(CLOCK_MONOTONIC));
+
+        /* And ensure that we'll send READY=1 again as soon as we are ready again */
+        m->ready_sent = false;
+}
+
 static bool generator_path_any(const char* const* paths) {
         bool found = false;
 
diff --git a/src/core/manager.h b/src/core/manager.h
index 75c16d6e26..87e63c3b68 100644
--- a/src/core/manager.h
+++ b/src/core/manager.h
@@ -535,6 +535,7 @@ void manager_send_unit_plymouth(Manager *m, Unit *u);
 bool manager_unit_inactive_or_pending(Manager *m, const char *name);
 
 void manager_check_finished(Manager *m);
+void manager_send_reloading(Manager *m);
 
 void disable_printk_ratelimit(void);
 void manager_recheck_dbus(Manager *m);
diff --git a/units/user@.service.in b/units/user@.service.in
index efbd5dfbc8..2c99f50905 100644
--- a/units/user@.service.in
+++ b/units/user@.service.in
@@ -17,7 +17,7 @@ IgnoreOnIsolate=yes
 [Service]
 User=%i
 PAMName=systemd-user
-Type=notify
+Type=notify-reload
 ExecStart={{ROOTLIBEXECDIR}}/systemd --user
 Slice=user-%i.slice
 KillMode=mixed