cgroup: drop "ignore_self" argument from cg_is_empty()

In all cases where the function (or cg_is_empty_recursive()) ignoring
the calling process is actually wrong, as a process keeps a cgroup busy
regardless if its the current one or another. Hence, let's simplify
things and drop the "ignore_self" parameter.

10 files changed, 28 insertions, 35 deletions

diff --git a/src/basic/cgroup-util.c b/src/basic/cgroup-util.c
index b9b27862ff..61681ada8d 100644
--- a/src/basic/cgroup-util.c
+++ b/src/basic/cgroup-util.c
@@ -891,49 +891,42 @@ int cg_uninstall_release_agent(const char *controller) {
         return 0;
 }
 
-int cg_is_empty(const char *controller, const char *path, bool ignore_self) {
+int cg_is_empty(const char *controller, const char *path) {
         _cleanup_fclose_ FILE *f = NULL;
-        pid_t pid = 0, self_pid;
-        bool found = false;
+        pid_t pid = 0;
         int r;
 
         assert(path);
 
         r = cg_enumerate_processes(controller, path, &f);
+        if (r == -ENOENT)
+                return 1;
         if (r < 0)
-                return r == -ENOENT ? 1 : r;
-
-        self_pid = getpid();
-
-        while ((r = cg_read_pid(f, &pid)) > 0) {
-
-                if (ignore_self && pid == self_pid)
-                        continue;
-
-                found = true;
-                break;
-        }
+                return r;
 
+        r = cg_read_pid(f, &pid);
         if (r < 0)
                 return r;
 
-        return !found;
+        return r == 0;
 }
 
-int cg_is_empty_recursive(const char *controller, const char *path, bool ignore_self) {
+int cg_is_empty_recursive(const char *controller, const char *path) {
         _cleanup_closedir_ DIR *d = NULL;
         char *fn;
         int r;
 
         assert(path);
 
-        r = cg_is_empty(controller, path, ignore_self);
+        r = cg_is_empty(controller, path);
         if (r <= 0)
                 return r;
 
         r = cg_enumerate_subgroups(controller, path, &d);
+        if (r == -ENOENT)
+                return 1;
         if (r < 0)
-                return r == -ENOENT ? 1 : r;
+                return r;
 
         while ((r = cg_read_subgroup(d, &fn)) > 0) {
                 _cleanup_free_ char *p = NULL;
@@ -943,7 +936,7 @@ int cg_is_empty_recursive(const char *controller, const char *path, bool ignore_
                 if (!p)
                         return -ENOMEM;
 
-                r = cg_is_empty_recursive(controller, p, ignore_self);
+                r = cg_is_empty_recursive(controller, p);
                 if (r <= 0)
                         return r;
         }
diff --git a/src/basic/cgroup-util.h b/src/basic/cgroup-util.h
index fd72e9e5c5..1c86581eb5 100644
--- a/src/basic/cgroup-util.h
+++ b/src/basic/cgroup-util.h
@@ -93,8 +93,8 @@ int cg_set_task_access(const char *controller, const char *path, mode_t mode, ui
 int cg_install_release_agent(const char *controller, const char *agent);
 int cg_uninstall_release_agent(const char *controller);
 
-int cg_is_empty(const char *controller, const char *path, bool ignore_self);
-int cg_is_empty_recursive(const char *controller, const char *path, bool ignore_self);
+int cg_is_empty(const char *controller, const char *path);
+int cg_is_empty_recursive(const char *controller, const char *path);
 
 int cg_get_root_path(char **path);
 
diff --git a/src/core/cgroup.c b/src/core/cgroup.c
index da6de68637..aafd75f424 100644
--- a/src/core/cgroup.c
+++ b/src/core/cgroup.c
@@ -1030,7 +1030,7 @@ int manager_notify_cgroup_empty(Manager *m, const char *cgroup) {
         if (!u)
                 return 0;
 
-        r = cg_is_empty_recursive(SYSTEMD_CGROUP_CONTROLLER, u->cgroup_path, true);
+        r = cg_is_empty_recursive(SYSTEMD_CGROUP_CONTROLLER, u->cgroup_path);
         if (r <= 0)
                 return r;
 
diff --git a/src/core/scope.c b/src/core/scope.c
index c594ab5294..1e94d63561 100644
--- a/src/core/scope.c
+++ b/src/core/scope.c
@@ -396,7 +396,7 @@ static bool scope_check_gc(Unit *u) {
         if (u->cgroup_path) {
                 int r;
 
-                r = cg_is_empty_recursive(SYSTEMD_CGROUP_CONTROLLER, u->cgroup_path, true);
+                r = cg_is_empty_recursive(SYSTEMD_CGROUP_CONTROLLER, u->cgroup_path);
                 if (r <= 0)
                         return true;
         }
diff --git a/src/core/service.c b/src/core/service.c
index a05ae95072..5a0a3aa867 100644
--- a/src/core/service.c
+++ b/src/core/service.c
@@ -1269,7 +1269,7 @@ static int cgroup_good(Service *s) {
         if (!UNIT(s)->cgroup_path)
                 return 0;
 
-        r = cg_is_empty_recursive(SYSTEMD_CGROUP_CONTROLLER, UNIT(s)->cgroup_path, true);
+        r = cg_is_empty_recursive(SYSTEMD_CGROUP_CONTROLLER, UNIT(s)->cgroup_path);
         if (r < 0)
                 return r;
 
diff --git a/src/login/loginctl.c b/src/login/loginctl.c
index 5fa98e069f..a7e64071cf 100644
--- a/src/login/loginctl.c
+++ b/src/login/loginctl.c
@@ -263,7 +263,7 @@ static int show_unit_cgroup(sd_bus *bus, const char *interface, const char *unit
         if (isempty(cgroup))
                 return 0;
 
-        if (cg_is_empty_recursive(SYSTEMD_CGROUP_CONTROLLER, cgroup, false) != 0 && leader <= 0)
+        if (cg_is_empty_recursive(SYSTEMD_CGROUP_CONTROLLER, cgroup) != 0 && leader <= 0)
                 return 0;
 
         c = columns();
diff --git a/src/machine/machinectl.c b/src/machine/machinectl.c
index 8bd0ed756b..bb8c5ac64b 100644
--- a/src/machine/machinectl.c
+++ b/src/machine/machinectl.c
@@ -375,7 +375,7 @@ static int show_unit_cgroup(sd_bus *bus, const char *unit, pid_t leader) {
         if (r < 0)
                 return bus_log_parse_error(r);
 
-        if (cg_is_empty_recursive(SYSTEMD_CGROUP_CONTROLLER, cgroup, false) != 0 && leader <= 0)
+        if (cg_is_empty_recursive(SYSTEMD_CGROUP_CONTROLLER, cgroup) != 0 && leader <= 0)
                 return 0;
 
         c = columns();
diff --git a/src/shared/cgroup-show.c b/src/shared/cgroup-show.c
index 3abccdb49a..31b4f6c684 100644
--- a/src/shared/cgroup-show.c
+++ b/src/shared/cgroup-show.c
@@ -152,7 +152,7 @@ int show_cgroup_by_path(const char *path, const char *prefix, unsigned n_columns
                 if (!k)
                         return -ENOMEM;
 
-                if (!(flags & OUTPUT_SHOW_ALL) && cg_is_empty_recursive(NULL, k, false) > 0)
+                if (!(flags & OUTPUT_SHOW_ALL) && cg_is_empty_recursive(NULL, k) > 0)
                         continue;
 
                 if (!shown_pids) {
diff --git a/src/systemctl/systemctl.c b/src/systemctl/systemctl.c
index 3cb5f61868..8d80aae182 100644
--- a/src/systemctl/systemctl.c
+++ b/src/systemctl/systemctl.c
@@ -3557,7 +3557,7 @@ static void print_status_info(
 
         if (i->control_group &&
             (i->main_pid > 0 || i->control_pid > 0 ||
-             ((arg_transport != BUS_TRANSPORT_LOCAL && arg_transport != BUS_TRANSPORT_MACHINE) || cg_is_empty_recursive(SYSTEMD_CGROUP_CONTROLLER, i->control_group, false) == 0))) {
+             ((arg_transport != BUS_TRANSPORT_LOCAL && arg_transport != BUS_TRANSPORT_MACHINE) || cg_is_empty_recursive(SYSTEMD_CGROUP_CONTROLLER, i->control_group) == 0))) {
                 unsigned c;
 
                 printf("   CGroup: %s\n", i->control_group);
diff --git a/src/test/test-cgroup.c b/src/test/test-cgroup.c
index 4be69a408d..8b0302cfe6 100644
--- a/src/test/test-cgroup.c
+++ b/src/test/test-cgroup.c
@@ -56,18 +56,18 @@ int main(int argc, char*argv[]) {
         assert_se(path_equal(path, "/sys/fs/cgroup/systemd/test-b/test-d"));
         free(path);
 
-        assert_se(cg_is_empty(SYSTEMD_CGROUP_CONTROLLER, "/test-a", false) > 0);
-        assert_se(cg_is_empty(SYSTEMD_CGROUP_CONTROLLER, "/test-b", false) > 0);
-        assert_se(cg_is_empty_recursive(SYSTEMD_CGROUP_CONTROLLER, "/test-a", false) > 0);
-        assert_se(cg_is_empty_recursive(SYSTEMD_CGROUP_CONTROLLER, "/test-b", false) == 0);
+        assert_se(cg_is_empty(SYSTEMD_CGROUP_CONTROLLER, "/test-a") > 0);
+        assert_se(cg_is_empty(SYSTEMD_CGROUP_CONTROLLER, "/test-b") > 0);
+        assert_se(cg_is_empty_recursive(SYSTEMD_CGROUP_CONTROLLER, "/test-a") > 0);
+        assert_se(cg_is_empty_recursive(SYSTEMD_CGROUP_CONTROLLER, "/test-b") == 0);
 
         assert_se(cg_kill_recursive(SYSTEMD_CGROUP_CONTROLLER, "/test-a", 0, false, false, false, NULL) == 0);
         assert_se(cg_kill_recursive(SYSTEMD_CGROUP_CONTROLLER, "/test-b", 0, false, false, false, NULL) > 0);
 
         assert_se(cg_migrate_recursive(SYSTEMD_CGROUP_CONTROLLER, "/test-b", SYSTEMD_CGROUP_CONTROLLER, "/test-a", false, false) > 0);
 
-        assert_se(cg_is_empty_recursive(SYSTEMD_CGROUP_CONTROLLER, "/test-a", false) == 0);
-        assert_se(cg_is_empty_recursive(SYSTEMD_CGROUP_CONTROLLER, "/test-b", false) > 0);
+        assert_se(cg_is_empty_recursive(SYSTEMD_CGROUP_CONTROLLER, "/test-a") == 0);
+        assert_se(cg_is_empty_recursive(SYSTEMD_CGROUP_CONTROLLER, "/test-b") > 0);
 
         assert_se(cg_kill_recursive(SYSTEMD_CGROUP_CONTROLLER, "/test-a", 0, false, false, false, NULL) > 0);
         assert_se(cg_kill_recursive(SYSTEMD_CGROUP_CONTROLLER, "/test-b", 0, false, false, false, NULL) == 0);