From: Lennart Poettering <lennart@poettering.net>
Date: Fri, 24 Apr 2015 13:27:19 +0000 (+0200)
Subject: Revert "core: do not spawn jobs or touch other units during coldplugging"
X-Git-Tag: v220~315
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=be847e82cf95bf8eb589778df2aa2b3d1d7ae99e;p=thirdparty%2Fsystemd.git

Revert "core: do not spawn jobs or touch other units during coldplugging"

This reverts commit 6e392c9c45643d106673c6643ac8bf4e65da13c1.

We really shouldn't invent external state keeping hashmaps, if we can
keep this state in the units themselves.
---

diff --git a/src/core/automount.c b/src/core/automount.c
index b3e96fc2e18..6fc214b7049 100644
--- a/src/core/automount.c
+++ b/src/core/automount.c
@@ -259,7 +259,7 @@ static void automount_set_state(Automount *a, AutomountState state) {
         unit_notify(UNIT(a), state_translation_table[old_state], state_translation_table[state], true);
 }
 
-static int automount_coldplug(Unit *u, Hashmap *deferred_work) {
+static int automount_coldplug(Unit *u) {
         Automount *a = AUTOMOUNT(u);
         int r;
 
diff --git a/src/core/busname.c b/src/core/busname.c
index b1b953aadf5..aba2a96c1a3 100644
--- a/src/core/busname.c
+++ b/src/core/busname.c
@@ -336,7 +336,7 @@ static void busname_set_state(BusName *n, BusNameState state) {
         unit_notify(UNIT(n), state_translation_table[old_state], state_translation_table[state], true);
 }
 
-static int busname_coldplug(Unit *u, Hashmap *deferred_work) {
+static int busname_coldplug(Unit *u) {
         BusName *n = BUSNAME(u);
         int r;
 
diff --git a/src/core/device.c b/src/core/device.c
index a7572306d70..63bae978a62 100644
--- a/src/core/device.c
+++ b/src/core/device.c
@@ -140,7 +140,7 @@ static void device_set_state(Device *d, DeviceState state) {
         unit_notify(UNIT(d), state_translation_table[old_state], state_translation_table[state], true);
 }
 
-static int device_coldplug(Unit *u, Hashmap *deferred_work) {
+static int device_coldplug(Unit *u) {
         Device *d = DEVICE(u);
 
         assert(d);
diff --git a/src/core/manager.c b/src/core/manager.c
index 2b04644dc1b..39a868fed63 100644
--- a/src/core/manager.c
+++ b/src/core/manager.c
@@ -981,28 +981,7 @@ static int manager_coldplug(Manager *m) {
         Unit *u;
         char *k;
 
-        /*
-         * Some unit types tend to spawn jobs or check other units' state
-         * during coldplug. This is wrong because it is undefined whether the
-         * units in question have been already coldplugged (i. e. their state
-         * restored). This way, we can easily re-start an already started unit
-         * or otherwise make a wrong decision based on the unit's state.
-         *
-         * Solve this by providing a way for coldplug functions to defer
-         * such actions until after all units have been coldplugged.
-         *
-         * We store Unit* -> int(*)(Unit*).
-         *
-         * https://bugs.freedesktop.org/show_bug.cgi?id=88401
-         */
-        _cleanup_hashmap_free_ Hashmap *deferred_work = NULL;
-        int(*proc)(Unit*);
-
-        assert(m);
-
-        deferred_work = hashmap_new(&trivial_hash_ops);
-        if (!deferred_work)
-                return -ENOMEM;
+        assert(m);
 
         /* Then, let's set up their initial state. */
         HASHMAP_FOREACH_KEY(u, k, m->units, i) {
@@ -1012,17 +991,7 @@ static int manager_coldplug(Manager *m) {
                 if (u->id != k)
                         continue;
 
-                q = unit_coldplug(u, deferred_work);
-                if (q < 0)
-                        r = q;
-        }
-
-        /* After coldplugging and setting up initial state of the units,
-         * let's perform operations which spawn jobs or query units' state. */
-        HASHMAP_FOREACH_KEY(proc, u, deferred_work, i) {
-                int q;
-
-                q = proc(u);
+                q = unit_coldplug(u);
                 if (q < 0)
                         r = q;
         }
diff --git a/src/core/mount.c b/src/core/mount.c
index d3a4098f1a4..eb25bcbdbe9 100644
--- a/src/core/mount.c
+++ b/src/core/mount.c
@@ -601,7 +601,7 @@ static void mount_set_state(Mount *m, MountState state) {
         m->reload_result = MOUNT_SUCCESS;
 }
 
-static int mount_coldplug(Unit *u, Hashmap *deferred_work) {
+static int mount_coldplug(Unit *u) {
         Mount *m = MOUNT(u);
         MountState new_state = MOUNT_DEAD;
         int r;
diff --git a/src/core/path.c b/src/core/path.c
index 6be9ac84bed..fbb695d87ff 100644
--- a/src/core/path.c
+++ b/src/core/path.c
@@ -438,12 +438,7 @@ static void path_set_state(Path *p, PathState state) {
 
 static void path_enter_waiting(Path *p, bool initial, bool recheck);
 
-static int path_enter_waiting_coldplug(Unit *u) {
-        path_enter_waiting(PATH(u), true, true);
-        return 0;
-}
-
-static int path_coldplug(Unit *u, Hashmap *deferred_work) {
+static int path_coldplug(Unit *u) {
         Path *p = PATH(u);
 
         assert(p);
@@ -452,10 +447,9 @@ static int path_coldplug(Unit *u, Hashmap *deferred_work) {
         if (p->deserialized_state != p->state) {
 
                 if (p->deserialized_state == PATH_WAITING ||
-                    p->deserialized_state == PATH_RUNNING) {
-                        hashmap_put(deferred_work, u, &path_enter_waiting_coldplug);
-                        path_set_state(p, PATH_WAITING);
-                } else
+                    p->deserialized_state == PATH_RUNNING)
+                        path_enter_waiting(p, true, true);
+                else
                         path_set_state(p, p->deserialized_state);
         }
 
diff --git a/src/core/scope.c b/src/core/scope.c
index 8b2bb29ed8a..1c3c6bb5409 100644
--- a/src/core/scope.c
+++ b/src/core/scope.c
@@ -171,7 +171,7 @@ static int scope_load(Unit *u) {
         return scope_verify(s);
 }
 
-static int scope_coldplug(Unit *u, Hashmap *deferred_work) {
+static int scope_coldplug(Unit *u) {
         Scope *s = SCOPE(u);
         int r;
 
diff --git a/src/core/service.c b/src/core/service.c
index 0e2f114135c..9104347f27a 100644
--- a/src/core/service.c
+++ b/src/core/service.c
@@ -879,7 +879,7 @@ static void service_set_state(Service *s, ServiceState state) {
         s->reload_result = SERVICE_SUCCESS;
 }
 
-static int service_coldplug(Unit *u, Hashmap *deferred_work) {
+static int service_coldplug(Unit *u) {
         Service *s = SERVICE(u);
         int r;
 
diff --git a/src/core/slice.c b/src/core/slice.c
index 0285c49aebf..0bebdbcbc64 100644
--- a/src/core/slice.c
+++ b/src/core/slice.c
@@ -150,7 +150,7 @@ static int slice_load(Unit *u) {
         return slice_verify(s);
 }
 
-static int slice_coldplug(Unit *u, Hashmap *deferred_work) {
+static int slice_coldplug(Unit *u) {
         Slice *t = SLICE(u);
 
         assert(t);
diff --git a/src/core/snapshot.c b/src/core/snapshot.c
index b1d8448771d..b70c3beb602 100644
--- a/src/core/snapshot.c
+++ b/src/core/snapshot.c
@@ -75,7 +75,7 @@ static int snapshot_load(Unit *u) {
         return 0;
 }
 
-static int snapshot_coldplug(Unit *u, Hashmap *deferred_work) {
+static int snapshot_coldplug(Unit *u) {
         Snapshot *s = SNAPSHOT(u);
 
         assert(s);
diff --git a/src/core/socket.c b/src/core/socket.c
index dd805d51df3..1f931eb986a 100644
--- a/src/core/socket.c
+++ b/src/core/socket.c
@@ -1323,7 +1323,7 @@ static void socket_set_state(Socket *s, SocketState state) {
         unit_notify(UNIT(s), state_translation_table[old_state], state_translation_table[state], true);
 }
 
-static int socket_coldplug(Unit *u, Hashmap *deferred_work) {
+static int socket_coldplug(Unit *u) {
         Socket *s = SOCKET(u);
         int r;
 
diff --git a/src/core/swap.c b/src/core/swap.c
index 76660cc9630..74f26b7a769 100644
--- a/src/core/swap.c
+++ b/src/core/swap.c
@@ -507,7 +507,7 @@ static void swap_set_state(Swap *s, SwapState state) {
                         job_add_to_run_queue(UNIT(other)->job);
 }
 
-static int swap_coldplug(Unit *u, Hashmap *deferred_work) {
+static int swap_coldplug(Unit *u) {
         Swap *s = SWAP(u);
         SwapState new_state = SWAP_DEAD;
         int r;
diff --git a/src/core/target.c b/src/core/target.c
index 5f644024759..8817ef21c4c 100644
--- a/src/core/target.c
+++ b/src/core/target.c
@@ -103,7 +103,7 @@ static int target_load(Unit *u) {
         return 0;
 }
 
-static int target_coldplug(Unit *u, Hashmap *deferred_work) {
+static int target_coldplug(Unit *u) {
         Target *t = TARGET(u);
 
         assert(t);
diff --git a/src/core/timer.c b/src/core/timer.c
index 79a7540553a..940550194b1 100644
--- a/src/core/timer.c
+++ b/src/core/timer.c
@@ -267,12 +267,7 @@ static void timer_set_state(Timer *t, TimerState state) {
 
 static void timer_enter_waiting(Timer *t, bool initial);
 
-static int timer_enter_waiting_coldplug(Unit *u) {
-        timer_enter_waiting(TIMER(u), false);
-        return 0;
-}
-
-static int timer_coldplug(Unit *u, Hashmap *deferred_work) {
+static int timer_coldplug(Unit *u) {
         Timer *t = TIMER(u);
 
         assert(t);
@@ -280,10 +275,9 @@ static int timer_coldplug(Unit *u, Hashmap *deferred_work) {
 
         if (t->deserialized_state != t->state) {
 
-                if (t->deserialized_state == TIMER_WAITING) {
-                        hashmap_put(deferred_work, u, &timer_enter_waiting_coldplug);
-                        timer_set_state(t, TIMER_WAITING);
-                } else
+                if (t->deserialized_state == TIMER_WAITING)
+                        timer_enter_waiting(t, false);
+                else
                         timer_set_state(t, t->deserialized_state);
         }
 
diff --git a/src/core/unit.c b/src/core/unit.c
index e921b48fc49..70a2b57fa3d 100644
--- a/src/core/unit.c
+++ b/src/core/unit.c
@@ -2875,34 +2875,27 @@ int unit_add_node_link(Unit *u, const char *what, bool wants) {
         return 0;
 }
 
-static int unit_add_deserialized_job_coldplug(Unit *u) {
-        int r;
-
-        r = manager_add_job(u->manager, u->deserialized_job, u, JOB_IGNORE_REQUIREMENTS, false, NULL, NULL);
-        if (r < 0)
-                return r;
-
-        u->deserialized_job = _JOB_TYPE_INVALID;
-
-        return 0;
-}
-
-int unit_coldplug(Unit *u, Hashmap *deferred_work) {
+int unit_coldplug(Unit *u) {
         int r;
 
         assert(u);
 
         if (UNIT_VTABLE(u)->coldplug)
-                if ((r = UNIT_VTABLE(u)->coldplug(u, deferred_work)) < 0)
+                if ((r = UNIT_VTABLE(u)->coldplug(u)) < 0)
                         return r;
 
         if (u->job) {
                 r = job_coldplug(u->job);
                 if (r < 0)
                         return r;
-        } else if (u->deserialized_job >= 0)
+        } else if (u->deserialized_job >= 0) {
                 /* legacy */
-                hashmap_put(deferred_work, u, &unit_add_deserialized_job_coldplug);
+                r = manager_add_job(u->manager, u->deserialized_job, u, JOB_IGNORE_REQUIREMENTS, false, NULL, NULL);
+                if (r < 0)
+                        return r;
+
+                u->deserialized_job = _JOB_TYPE_INVALID;
+        }
 
         return 0;
 }
diff --git a/src/core/unit.h b/src/core/unit.h
index 260dc451c7b..be306a004b8 100644
--- a/src/core/unit.h
+++ b/src/core/unit.h
@@ -303,14 +303,8 @@ struct UnitVTable {
         int (*load)(Unit *u);
 
         /* If a lot of units got created via enumerate(), this is
-         * where to actually set the state and call unit_notify().
-         *
-         * This must not reference other units (maybe implicitly through spawning
-         * jobs), because it is possible that they are not yet coldplugged.
-         * Such actions must be deferred until the end of coldplug bу adding
-         * a "Unit* -> int(*)(Unit*)" entry into the hashmap.
-         */
-        int (*coldplug)(Unit *u, Hashmap *deferred_work);
+         * where to actually set the state and call unit_notify(). */
+        int (*coldplug)(Unit *u);
 
         void (*dump)(Unit *u, FILE *f, const char *prefix);
 
@@ -546,7 +540,7 @@ int unit_deserialize(Unit *u, FILE *f, FDSet *fds);
 
 int unit_add_node_link(Unit *u, const char *what, bool wants);
 
-int unit_coldplug(Unit *u, Hashmap *deferred_work);
+int unit_coldplug(Unit *u);
 
 void unit_status_printf(Unit *u, const char *status, const char *unit_status_msg_format) _printf_(3, 0);