1 /*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
4 This file is part of systemd.
6 Copyright 2010 Lennart Poettering
8 systemd is free software; you can redistribute it and/or modify it
9 under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 2 of the License, or
11 (at your option) any later version.
13 systemd is distributed in the hope that it will be useful, but
14 WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with systemd; If not, see <http://www.gnu.org/licenses/>.
25 #include <sys/types.h>
27 #include <sys/mount.h>
31 #include "cgroup-util.h"
34 int cgroup_bonding_realize(CGroupBonding *b) {
39 assert(b->controller);
44 if ((r = cg_create(b->controller, b->path)) < 0)
49 if (b->only_us && b->clean_up)
50 cg_trim(b->controller, b->path, false);
55 int cgroup_bonding_realize_list(CGroupBonding *first) {
59 LIST_FOREACH(by_unit, b, first)
60 if ((r = cgroup_bonding_realize(b)) < 0)
66 void cgroup_bonding_free(CGroupBonding *b) {
72 LIST_REMOVE(CGroupBonding, by_unit, b->unit->meta.cgroup_bondings, b);
74 assert_se(f = hashmap_get(b->unit->meta.manager->cgroup_bondings, b->path));
75 LIST_REMOVE(CGroupBonding, by_path, f, b);
78 hashmap_replace(b->unit->meta.manager->cgroup_bondings, b->path, f);
80 hashmap_remove(b->unit->meta.manager->cgroup_bondings, b->path);
83 if (b->realized && b->only_us && b->clean_up) {
85 if (cgroup_bonding_is_empty(b) > 0)
86 cg_delete(b->controller, b->path);
88 cg_trim(b->controller, b->path, false);
96 void cgroup_bonding_free_list(CGroupBonding *first) {
99 LIST_FOREACH_SAFE(by_unit, b, n, first)
100 cgroup_bonding_free(b);
103 void cgroup_bonding_trim(CGroupBonding *b, bool delete_root) {
106 if (b->realized && b->only_us && b->clean_up)
107 cg_trim(b->controller, b->path, delete_root);
110 void cgroup_bonding_trim_list(CGroupBonding *first, bool delete_root) {
113 LIST_FOREACH(by_unit, b, first)
114 cgroup_bonding_trim(b, delete_root);
117 int cgroup_bonding_install(CGroupBonding *b, pid_t pid) {
123 if ((r = cg_create_and_attach(b->controller, b->path, pid)) < 0)
130 int cgroup_bonding_install_list(CGroupBonding *first, pid_t pid) {
134 LIST_FOREACH(by_unit, b, first)
135 if ((r = cgroup_bonding_install(b, pid)) < 0)
141 int cgroup_bonding_kill(CGroupBonding *b, int sig, Set *s) {
147 if ((r = cgroup_bonding_realize(b)) < 0)
152 return cg_kill_recursive(b->controller, b->path, sig, true, false, s);
155 int cgroup_bonding_kill_list(CGroupBonding *first, int sig, Set *s) {
157 Set *allocated_set = NULL;
158 int ret = -EAGAIN, r;
161 if (!(s = allocated_set = set_new(trivial_hash_func, trivial_compare_func)))
164 LIST_FOREACH(by_unit, b, first) {
165 if ((r = cgroup_bonding_kill(b, sig, s)) < 0) {
166 if (r == -EAGAIN || r == -ESRCH)
173 if (ret < 0 || r > 0)
179 set_free(allocated_set);
184 /* Returns 1 if the group is empty, 0 if it is not, -EAGAIN if we
186 int cgroup_bonding_is_empty(CGroupBonding *b) {
191 if ((r = cg_is_empty_recursive(b->controller, b->path, true)) < 0)
194 /* If it is empty it is empty */
198 /* It's not only us using this cgroup, so we just don't know */
199 return b->only_us ? 0 : -EAGAIN;
202 int cgroup_bonding_is_empty_list(CGroupBonding *first) {
205 LIST_FOREACH(by_unit, b, first) {
208 if ((r = cgroup_bonding_is_empty(b)) < 0) {
209 /* If this returned -EAGAIN, then we don't know if the
210 * group is empty, so let's see if another group can
222 int manager_setup_cgroup(Manager *m) {
223 char *current = NULL, *path = NULL;
229 /* 1. Determine hierarchy */
230 if ((r = cg_get_by_pid(SYSTEMD_CGROUP_CONTROLLER, 0, ¤t)) < 0)
233 if (m->running_as == MANAGER_SYSTEM)
234 strcpy(suffix, "/system");
236 snprintf(suffix, sizeof(suffix), "/systemd-%lu", (unsigned long) getpid());
237 char_array_0(suffix);
240 free(m->cgroup_hierarchy);
241 if (endswith(current, suffix)) {
242 /* We probably got reexecuted and can continue to use our root cgroup */
243 m->cgroup_hierarchy = current;
247 /* We need a new root cgroup */
248 m->cgroup_hierarchy = NULL;
249 if (asprintf(&m->cgroup_hierarchy, "%s%s", streq(current, "/") ? "" : current, suffix) < 0) {
256 if ((r = cg_get_path(SYSTEMD_CGROUP_CONTROLLER, m->cgroup_hierarchy, NULL, &path)) < 0)
259 log_debug("Using cgroup controller " SYSTEMD_CGROUP_CONTROLLER ". File system hierarchy is at %s.", path);
261 /* 3. Install agent */
262 if ((r = cg_install_release_agent(SYSTEMD_CGROUP_CONTROLLER, SYSTEMD_CGROUP_AGENT_PATH)) < 0)
263 log_warning("Failed to install release agent, ignoring: %s", strerror(-r));
265 log_debug("Installed release agent.");
267 log_debug("Release agent already installed.");
269 /* 4. Realize the group */
270 if ((r = cg_create_and_attach(SYSTEMD_CGROUP_CONTROLLER, m->cgroup_hierarchy, 0)) < 0) {
271 log_error("Failed to create root cgroup hierarchy: %s", strerror(-r));
275 /* 5. And pin it, so that it cannot be unmounted */
276 if (m->pin_cgroupfs_fd >= 0)
277 close_nointr_nofail(m->pin_cgroupfs_fd);
279 if ((m->pin_cgroupfs_fd = open(path, O_RDONLY|O_CLOEXEC|O_DIRECTORY|O_NOCTTY|O_NONBLOCK)) < 0) {
284 log_debug("Created root group.");
293 void manager_shutdown_cgroup(Manager *m, bool delete) {
296 if (delete && m->cgroup_hierarchy)
297 cg_delete(SYSTEMD_CGROUP_CONTROLLER, m->cgroup_hierarchy);
299 if (m->pin_cgroupfs_fd >= 0) {
300 close_nointr_nofail(m->pin_cgroupfs_fd);
301 m->pin_cgroupfs_fd = -1;
304 free(m->cgroup_hierarchy);
305 m->cgroup_hierarchy = NULL;
308 int cgroup_notify_empty(Manager *m, const char *group) {
309 CGroupBonding *l, *b;
314 if (!(l = hashmap_get(m->cgroup_bondings, group)))
317 LIST_FOREACH(by_path, b, l) {
323 if ((t = cgroup_bonding_is_empty_list(b)) < 0) {
325 /* If we don't know, we don't know */
327 log_warning("Failed to check whether cgroup is empty: %s", strerror(errno));
333 if (UNIT_VTABLE(b->unit)->cgroup_notify_empty)
334 UNIT_VTABLE(b->unit)->cgroup_notify_empty(b->unit);
340 Unit* cgroup_unit_by_pid(Manager *m, pid_t pid) {
341 CGroupBonding *l, *b;
349 if (cg_get_by_pid(SYSTEMD_CGROUP_CONTROLLER, pid, &group) < 0)
352 l = hashmap_get(m->cgroup_bondings, group);
357 while ((slash = strrchr(group, '/'))) {
363 if ((l = hashmap_get(m->cgroup_bondings, group)))
370 LIST_FOREACH(by_path, b, l) {
382 CGroupBonding *cgroup_bonding_find_list(CGroupBonding *first, const char *controller) {
387 LIST_FOREACH(by_unit, b, first)
388 if (streq(b->controller, controller))
394 char *cgroup_bonding_to_string(CGroupBonding *b) {
399 if (asprintf(&r, "%s:%s", b->controller, b->path) < 0)
405 pid_t cgroup_bonding_search_main_pid(CGroupBonding *b) {
415 if ((r = cg_enumerate_processes(b->controller, b->path, &f)) < 0)
418 while ((r = cg_read_pid(f, &npid)) > 0) {
424 /* Dang, there's more than one PID in this
425 * group, so we don't know what process is the
439 pid_t cgroup_bonding_search_main_pid_list(CGroupBonding *first) {
443 /* Try to find a main pid from this cgroup, but checking if
444 * there's only one PID in the cgroup and returning it. Later
445 * on we might want to add additional, smarter heuristics
448 LIST_FOREACH(by_unit, b, first)
449 if ((pid = cgroup_bonding_search_main_pid(b)) != 0)