base/SOURCES/0628-core-fix-confusing-logging-of-instantaneous-jobs.patch

From 7bc07eb6c9a31f2c26d0fe3e6d7a26a13cbb2369 Mon Sep 17 00:00:00 2001
From: Michal Schmidt <mschmidt@redhat.com>
Date: Thu, 16 Jul 2015 20:08:30 +0200
Subject: [PATCH] core: fix confusing logging of instantaneous jobs

For instantaneous jobs (e.g. starting of targets, sockets, slices, or
Type=simple services) the log shows the job completion
before starting:

        systemd[1]: Created slice -.slice.
        systemd[1]: Starting -.slice.
        systemd[1]: Created slice System Slice.
        systemd[1]: Starting System Slice.
        systemd[1]: Listening on Journal Audit Socket.
        systemd[1]: Starting Journal Audit Socket.
        systemd[1]: Reached target Timers.
        systemd[1]: Starting Timers.
        ...

The reason is that the job completes before the ->start() method returns
and only then does unit_start() print the "Starting ..." message.
The same thing happens when stopping units.

Rather than fixing the order of the messages, let's just not emit the
Starting/Stopping message at all when the job completes instantaneously.
The job completion message is sufficient in this case.

(cherry picked from commit d1a34ae9c20f1c02aab17884919eccef572b1d21)

Resolves: #1506256
---
 src/core/job.c  | 65 +++++++++++++++++++++++++++++++++++++++------------------
 src/core/unit.c | 36 +++++++++++---------------------
 src/core/unit.h |  1 +
 3 files changed, 58 insertions(+), 44 deletions(-)

diff --git a/src/core/job.c b/src/core/job.c
index c9a43a4cb..612caa604 100644
--- a/src/core/job.c
+++ b/src/core/job.c
@@ -504,10 +504,48 @@ static void job_change_type(Job *j, JobType newtype) {
         j->type = newtype;
 }
 
+static int job_perform_on_unit(Job **j) {
+        /* While we execute this operation the job might go away (for
+         * example: because it finishes immediately or is replaced by a new,
+         * conflicting job.) To make sure we don't access a freed job later on
+         * we store the id here, so that we can verify the job is still
+         * valid. */
+        Manager *m  = (*j)->manager;
+        Unit *u     = (*j)->unit;
+        JobType t   = (*j)->type;
+        uint32_t id = (*j)->id;
+        int r;
+
+        switch (t) {
+                case JOB_START:
+                        r = unit_start(u);
+                        break;
+
+                case JOB_RESTART:
+                        t = JOB_STOP;
+                case JOB_STOP:
+                        r = unit_stop(u);
+                        break;
+
+                case JOB_RELOAD:
+                        r = unit_reload(u);
+                        break;
+
+                default:
+                        assert_not_reached("Invalid job type");
+        }
+
+        /* Log if the job still exists and the start/stop/reload function
+         * actually did something. */
+        *j = manager_get_job(m, id);
+        if (*j && r > 0)
+                unit_status_emit_starting_stopping_reloading(u, t);
+
+        return r;
+}
+
 int job_run_and_invalidate(Job *j) {
         int r;
-        uint32_t id;
-        Manager *m = j->manager;
 
         assert(j);
         assert(j->installed);
@@ -526,23 +564,9 @@ int job_run_and_invalidate(Job *j) {
         job_set_state(j, JOB_RUNNING);
         job_add_to_dbus_queue(j);
 
-        /* While we execute this operation the job might go away (for
-         * example: because it is replaced by a new, conflicting
-         * job.) To make sure we don't access a freed job later on we
-         * store the id here, so that we can verify the job is still
-         * valid. */
-        id = j->id;
 
         switch (j->type) {
 
-                case JOB_START:
-                        r = unit_start(j->unit);
-
-                        /* If this unit cannot be started, then simply wait */
-                        if (r == -EBADR)
-                                r = 0;
-                        break;
-
                 case JOB_VERIFY_ACTIVE: {
                         UnitActiveState t = unit_active_state(j->unit);
                         if (UNIT_IS_ACTIVE_OR_RELOADING(t))
@@ -554,17 +578,19 @@ int job_run_and_invalidate(Job *j) {
                         break;
                 }
 
+                case JOB_START:
                 case JOB_STOP:
                 case JOB_RESTART:
-                        r = unit_stop(j->unit);
+                        r = job_perform_on_unit(&j);
 
-                        /* If this unit cannot stopped, then simply wait. */
+                        /* If the unit type does not support starting/stopping,
+                         * then simply wait. */
                         if (r == -EBADR)
                                 r = 0;
                         break;
 
                 case JOB_RELOAD:
-                        r = unit_reload(j->unit);
+                        r = job_perform_on_unit(&j);
                         break;
 
                 case JOB_NOP:
@@ -575,7 +601,6 @@ int job_run_and_invalidate(Job *j) {
                         assert_not_reached("Unknown job type");
         }
 
-        j = manager_get_job(m, id);
         if (j) {
                 if (r == -EALREADY)
                         r = job_finish_and_invalidate(j, JOB_DONE, true, true);
diff --git a/src/core/unit.c b/src/core/unit.c
index 6d535ae12..907a4bf7f 100644
--- a/src/core/unit.c
+++ b/src/core/unit.c
@@ -1417,6 +1417,15 @@ static void unit_status_log_starting_stopping_reloading(Unit *u, JobType t) {
                         NULL);
 }
 
+void unit_status_emit_starting_stopping_reloading(Unit *u, JobType t) {
+
+        unit_status_log_starting_stopping_reloading(u, t);
+
+        /* Reload status messages have traditionally not been printed to console. */
+        if (t != JOB_RELOAD)
+                unit_status_print_starting_stopping(u, t);
+}
+
 /* Errors:
  *         -EBADR:     This unit type does not support starting.
  *         -EALREADY:  Unit is already started.
@@ -1427,7 +1436,6 @@ static void unit_status_log_starting_stopping_reloading(Unit *u, JobType t) {
 int unit_start(Unit *u) {
         UnitActiveState state;
         Unit *following;
-        int r;
 
         assert(u);
 
@@ -1481,14 +1489,7 @@ int unit_start(Unit *u) {
 
         unit_add_to_dbus_queue(u);
 
-        r = UNIT_VTABLE(u)->start(u);
-        if (r <= 0)
-                return r;
-
-        /* Log if the start function actually did something */
-        unit_status_log_starting_stopping_reloading(u, JOB_START);
-        unit_status_print_starting_stopping(u, JOB_START);
-        return r;
+        return UNIT_VTABLE(u)->start(u);
 }
 
 bool unit_can_start(Unit *u) {
@@ -1512,7 +1513,6 @@ bool unit_can_isolate(Unit *u) {
 int unit_stop(Unit *u) {
         UnitActiveState state;
         Unit *following;
-        int r;
 
         assert(u);
 
@@ -1531,13 +1531,7 @@ int unit_stop(Unit *u) {
 
         unit_add_to_dbus_queue(u);
 
-        r = UNIT_VTABLE(u)->stop(u);
-        if (r <= 0)
-                return r;
-
-        unit_status_log_starting_stopping_reloading(u, JOB_STOP);
-        unit_status_print_starting_stopping(u, JOB_STOP);
-        return r;
+        return UNIT_VTABLE(u)->stop(u);
 }
 
 /* Errors:
@@ -1548,7 +1542,6 @@ int unit_stop(Unit *u) {
 int unit_reload(Unit *u) {
         UnitActiveState state;
         Unit *following;
-        int r;
 
         assert(u);
 
@@ -1575,12 +1568,7 @@ int unit_reload(Unit *u) {
 
         unit_add_to_dbus_queue(u);
 
-        r = UNIT_VTABLE(u)->reload(u);
-        if (r <= 0)
-                return r;
-
-        unit_status_log_starting_stopping_reloading(u, JOB_RELOAD);
-        return r;
+        return UNIT_VTABLE(u)->reload(u);
 }
 
 bool unit_can_reload(Unit *u) {
diff --git a/src/core/unit.h b/src/core/unit.h
index 85f52df18..480e2e95f 100644
--- a/src/core/unit.h
+++ b/src/core/unit.h
@@ -562,6 +562,7 @@ int unit_add_node_link(Unit *u, const char *what, bool wants, UnitDependency d);
 int unit_coldplug(Unit *u, Hashmap *deferred_work);
 
 void unit_status_printf(Unit *u, const char *status, const char *unit_status_msg_format) _printf_(3, 0);
+void unit_status_emit_starting_stopping_reloading(Unit *u, JobType t);
 
 bool unit_need_daemon_reload(Unit *u);