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)
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 && b->essential)
66 void cgroup_bonding_free(CGroupBonding *b) {
72 LIST_REMOVE(CGroupBonding, by_unit, b->unit->meta.cgroup_bondings, b);
74 if (streq(b->controller, SYSTEMD_CGROUP_CONTROLLER)) {
75 assert_se(f = hashmap_get(b->unit->meta.manager->cgroup_bondings, b->path));
76 LIST_REMOVE(CGroupBonding, by_path, f, b);
79 hashmap_replace(b->unit->meta.manager->cgroup_bondings, b->path, f);
81 hashmap_remove(b->unit->meta.manager->cgroup_bondings, b->path);
85 if (b->realized && b->ours) {
87 if (cgroup_bonding_is_empty(b) > 0)
88 cg_delete(b->controller, b->path);
90 cg_trim(b->controller, b->path, false);
98 void cgroup_bonding_free_list(CGroupBonding *first) {
101 LIST_FOREACH_SAFE(by_unit, b, n, first)
102 cgroup_bonding_free(b);
105 void cgroup_bonding_trim(CGroupBonding *b, bool delete_root) {
108 if (b->realized && b->ours)
109 cg_trim(b->controller, b->path, delete_root);
112 void cgroup_bonding_trim_list(CGroupBonding *first, bool delete_root) {
115 LIST_FOREACH(by_unit, b, first)
116 cgroup_bonding_trim(b, delete_root);
119 int cgroup_bonding_install(CGroupBonding *b, pid_t pid) {
125 if ((r = cg_create_and_attach(b->controller, b->path, pid)) < 0)
132 int cgroup_bonding_install_list(CGroupBonding *first, pid_t pid) {
136 LIST_FOREACH(by_unit, b, first)
137 if ((r = cgroup_bonding_install(b, pid)) < 0 && b->essential)
143 int cgroup_bonding_kill(CGroupBonding *b, int sig, bool sigcont, Set *s) {
147 /* Don't kill cgroups that aren't ours */
148 if (!b->realized || !b->ours)
151 return cg_kill_recursive(b->controller, b->path, sig, sigcont, true, false, s);
154 int cgroup_bonding_kill_list(CGroupBonding *first, int sig, bool sigcont, Set *s) {
156 Set *allocated_set = NULL;
157 int ret = -EAGAIN, r;
160 if (!(s = allocated_set = set_new(trivial_hash_func, trivial_compare_func)))
163 LIST_FOREACH(by_unit, b, first) {
164 if ((r = cgroup_bonding_kill(b, sig, sigcont, s)) < 0) {
165 if (r == -EAGAIN || r == -ESRCH)
172 if (ret < 0 || r > 0)
178 set_free(allocated_set);
183 /* Returns 1 if the group is empty, 0 if it is not, -EAGAIN if we
185 int cgroup_bonding_is_empty(CGroupBonding *b) {
190 if ((r = cg_is_empty_recursive(b->controller, b->path, true)) < 0)
193 /* If it is empty it is empty */
197 /* It's not only us using this cgroup, so we just don't know */
198 return b->ours ? 0 : -EAGAIN;
201 int cgroup_bonding_is_empty_list(CGroupBonding *first) {
204 LIST_FOREACH(by_unit, b, first) {
207 if ((r = cgroup_bonding_is_empty(b)) < 0) {
208 /* If this returned -EAGAIN, then we don't know if the
209 * group is empty, so let's see if another group can
221 int manager_setup_cgroup(Manager *m) {
222 char *current = NULL, *path = NULL;
228 /* 1. Determine hierarchy */
229 if ((r = cg_get_by_pid(SYSTEMD_CGROUP_CONTROLLER, 0, ¤t)) < 0) {
230 log_error("Cannot determine cgroup we are running in: %s", strerror(-r));
234 if (m->running_as == MANAGER_SYSTEM)
235 strcpy(suffix, "/system");
237 snprintf(suffix, sizeof(suffix), "/systemd-%lu", (unsigned long) getpid());
238 char_array_0(suffix);
241 free(m->cgroup_hierarchy);
242 if (endswith(current, suffix)) {
243 /* We probably got reexecuted and can continue to use our root cgroup */
244 m->cgroup_hierarchy = current;
248 /* We need a new root cgroup */
249 m->cgroup_hierarchy = NULL;
250 if (asprintf(&m->cgroup_hierarchy, "%s%s", streq(current, "/") ? "" : current, suffix) < 0) {
251 log_error("Out of memory");
258 if ((r = cg_get_path(SYSTEMD_CGROUP_CONTROLLER, m->cgroup_hierarchy, NULL, &path)) < 0) {
259 log_error("Cannot find cgroup mount point: %s", strerror(-r));
263 log_debug("Using cgroup controller " SYSTEMD_CGROUP_CONTROLLER ". File system hierarchy is at %s.", path);
265 /* 3. Install agent */
266 if ((r = cg_install_release_agent(SYSTEMD_CGROUP_CONTROLLER, SYSTEMD_CGROUP_AGENT_PATH)) < 0)
267 log_warning("Failed to install release agent, ignoring: %s", strerror(-r));
269 log_debug("Installed release agent.");
271 log_debug("Release agent already installed.");
273 /* 4. Realize the group */
274 if ((r = cg_create_and_attach(SYSTEMD_CGROUP_CONTROLLER, m->cgroup_hierarchy, 0)) < 0) {
275 log_error("Failed to create root cgroup hierarchy: %s", strerror(-r));
279 /* 5. And pin it, so that it cannot be unmounted */
280 if (m->pin_cgroupfs_fd >= 0)
281 close_nointr_nofail(m->pin_cgroupfs_fd);
283 if ((m->pin_cgroupfs_fd = open(path, O_RDONLY|O_CLOEXEC|O_DIRECTORY|O_NOCTTY|O_NONBLOCK)) < 0) {
284 log_error("Failed to open pin file: %m");
289 log_debug("Created root group.");
298 void manager_shutdown_cgroup(Manager *m, bool delete) {
301 if (delete && m->cgroup_hierarchy)
302 cg_delete(SYSTEMD_CGROUP_CONTROLLER, m->cgroup_hierarchy);
304 if (m->pin_cgroupfs_fd >= 0) {
305 close_nointr_nofail(m->pin_cgroupfs_fd);
306 m->pin_cgroupfs_fd = -1;
309 free(m->cgroup_hierarchy);
310 m->cgroup_hierarchy = NULL;
313 int cgroup_notify_empty(Manager *m, const char *group) {
314 CGroupBonding *l, *b;
319 if (!(l = hashmap_get(m->cgroup_bondings, group)))
322 LIST_FOREACH(by_path, b, l) {
328 if ((t = cgroup_bonding_is_empty_list(b)) < 0) {
330 /* If we don't know, we don't know */
332 log_warning("Failed to check whether cgroup is empty: %s", strerror(errno));
338 if (UNIT_VTABLE(b->unit)->cgroup_notify_empty)
339 UNIT_VTABLE(b->unit)->cgroup_notify_empty(b->unit);
345 Unit* cgroup_unit_by_pid(Manager *m, pid_t pid) {
346 CGroupBonding *l, *b;
354 if (cg_get_by_pid(SYSTEMD_CGROUP_CONTROLLER, pid, &group) < 0)
357 l = hashmap_get(m->cgroup_bondings, group);
362 while ((slash = strrchr(group, '/'))) {
368 if ((l = hashmap_get(m->cgroup_bondings, group)))
375 LIST_FOREACH(by_path, b, l) {
387 CGroupBonding *cgroup_bonding_find_list(CGroupBonding *first, const char *controller) {
392 LIST_FOREACH(by_unit, b, first)
393 if (streq(b->controller, controller))
399 char *cgroup_bonding_to_string(CGroupBonding *b) {
404 if (asprintf(&r, "%s:%s", b->controller, b->path) < 0)
410 pid_t cgroup_bonding_search_main_pid(CGroupBonding *b) {
412 pid_t pid = 0, npid, mypid;
419 if (cg_enumerate_processes(b->controller, b->path, &f) < 0)
424 while (cg_read_pid(f, &npid) > 0) {
430 /* Ignore processes that aren't our kids */
431 if (get_parent_of_pid(npid, &ppid) >= 0 && ppid != mypid)
435 /* Dang, there's more than one daemonized PID
436 in this group, so we don't know what process
437 is the main process. */
450 pid_t cgroup_bonding_search_main_pid_list(CGroupBonding *first) {
454 /* Try to find a main pid from this cgroup, but checking if
455 * there's only one PID in the cgroup and returning it. Later
456 * on we might want to add additional, smarter heuristics
459 LIST_FOREACH(by_unit, b, first)
460 if ((pid = cgroup_bonding_search_main_pid(b)) != 0)