scope: make attachment of initial PIDs a bit more robust

4 files changed, 33 insertions, 18 deletions

diff --git a/src/core/cgroup.c b/src/core/cgroup.c
index 83678e6e03..35b862d5c2 100644
--- a/src/core/cgroup.c
+++ b/src/core/cgroup.c
@@ -605,7 +605,6 @@ static const char *migrate_callback(CGroupControllerMask mask, void *userdata) {
 }
 
 static int unit_create_cgroups(Unit *u, CGroupControllerMask mask) {
-        _cleanup_free_ char *path = NULL;
         CGroupContext *c;
         int r;
 
@@ -615,18 +614,22 @@ static int unit_create_cgroups(Unit *u, CGroupControllerMask mask) {
         if (!c)
                 return 0;
 
-        path = unit_default_cgroup_path(u);
-        if (!path)
-                return log_oom();
+        if (!u->cgroup_path) {
+                _cleanup_free_ char *path = NULL;
 
-        r = hashmap_put(u->manager->cgroup_unit, path, u);
-        if (r < 0) {
-                log_error(r == -EEXIST ? "cgroup %s exists already: %s" : "hashmap_put failed for %s: %s", path, strerror(-r));
-                return r;
-        }
-        if (r > 0) {
-                u->cgroup_path = path;
-                path = NULL;
+                path = unit_default_cgroup_path(u);
+                if (!path)
+                        return log_oom();
+
+                r = hashmap_put(u->manager->cgroup_unit, path, u);
+                if (r < 0) {
+                        log_error(r == -EEXIST ? "cgroup %s exists already: %s" : "hashmap_put failed for %s: %s", path, strerror(-r));
+                        return r;
+                }
+                if (r > 0) {
+                        u->cgroup_path = path;
+                        path = NULL;
+                }
         }
 
         /* First, create our own group */
@@ -651,6 +654,21 @@ static int unit_create_cgroups(Unit *u, CGroupControllerMask mask) {
         return 0;
 }
 
+int unit_attach_pids_to_cgroup(Unit *u) {
+        int r;
+        assert(u);
+
+        r = unit_realize_cgroup(u);
+        if (r < 0)
+                return r;
+
+        r = cg_attach_many_everywhere(u->manager->cgroup_supported, u->cgroup_path, u->pids, migrate_callback, u);
+        if (r < 0)
+                return r;
+
+        return 0;
+}
+
 static bool unit_has_mask_realized(Unit *u, CGroupControllerMask mask) {
         assert(u);
 
diff --git a/src/core/cgroup.h b/src/core/cgroup.h
index 16d661357b..7150e5e7e2 100644
--- a/src/core/cgroup.h
+++ b/src/core/cgroup.h
@@ -110,6 +110,7 @@ CGroupControllerMask unit_get_target_mask(Unit *u);
 void unit_update_cgroup_members_masks(Unit *u);
 int unit_realize_cgroup(Unit *u);
 void unit_destroy_cgroup_if_empty(Unit *u);
+int unit_attach_pids_to_cgroup(Unit *u);
 
 int manager_setup_cgroup(Manager *m);
 void manager_shutdown_cgroup(Manager *m, bool delete);
diff --git a/src/core/execute.c b/src/core/execute.c
index 955090c446..5e4135e030 100644
--- a/src/core/execute.c
+++ b/src/core/execute.c
@@ -1351,7 +1351,7 @@ static int exec_child(ExecCommand *command,
         }
 
         if (params->cgroup_path) {
-                err = cg_attach_everywhere(params->cgroup_supported, params->cgroup_path, 0);
+                err = cg_attach_everywhere(params->cgroup_supported, params->cgroup_path, 0, NULL, NULL);
                 if (err < 0) {
                         *error = EXIT_CGROUP;
                         return err;
diff --git a/src/core/scope.c b/src/core/scope.c
index f0efec0516..e0da6e4db7 100644
--- a/src/core/scope.c
+++ b/src/core/scope.c
@@ -288,11 +288,7 @@ static int scope_start(Unit *u) {
         if (!u->transient && UNIT(s)->manager->n_reloading <= 0)
                 return -ENOENT;
 
-        r = unit_realize_cgroup(u);
-        if (r < 0)
-                return log_error_errno(r, "Failed to realize cgroup: %m");
-
-        r = cg_attach_many_everywhere(u->manager->cgroup_supported, u->cgroup_path, UNIT(s)->pids);
+        r = unit_attach_pids_to_cgroup(u);
         if (r < 0)
                 return r;