1 /*-*- Mode: C; c-basic-offset: 8 -*-*/
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>
32 static int translate_error(int error, int _errno) {
36 case ECGROUPNOTCOMPILED:
37 case ECGROUPNOTMOUNTED:
39 case ECGROUPNOTCREATED:
45 case ECGROUPNOTALLOWED:
55 int cgroup_bonding_realize(CGroupBonding *b) {
60 assert(b->controller);
65 if (!(b->cgroup = cgroup_new_cgroup(b->path)))
68 if (!cgroup_add_controller(b->cgroup, b->controller)) {
74 r = cgroup_create_cgroup_from_parent(b->cgroup, true);
76 r = cgroup_create_cgroup(b->cgroup, true);
79 r = translate_error(r, errno);
86 cgroup_free(&b->cgroup);
91 int cgroup_bonding_realize_list(CGroupBonding *first) {
94 LIST_FOREACH(by_unit, b, first) {
97 if ((r = cgroup_bonding_realize(b)) < 0)
104 void cgroup_bonding_free(CGroupBonding *b) {
110 LIST_REMOVE(CGroupBonding, by_unit, b->unit->meta.cgroup_bondings, b);
112 assert_se(f = hashmap_get(b->unit->meta.manager->cgroup_bondings, b->path));
113 LIST_REMOVE(CGroupBonding, by_path, f, b);
116 hashmap_replace(b->unit->meta.manager->cgroup_bondings, b->path, f);
118 hashmap_remove(b->unit->meta.manager->cgroup_bondings, b->path);
126 if (b->only_us && b->clean_up)
127 cgroup_delete_cgroup(b->cgroup, true);
129 cgroup_free(&b->cgroup);
135 void cgroup_bonding_free_list(CGroupBonding *first) {
136 CGroupBonding *b, *n;
138 LIST_FOREACH_SAFE(by_unit, b, n, first)
139 cgroup_bonding_free(b);
142 int cgroup_bonding_install(CGroupBonding *b, pid_t pid) {
154 if ((r = cgroup_attach_task_pid(b->cgroup, pid)))
155 return translate_error(r, errno);
160 int cgroup_bonding_install_list(CGroupBonding *first, pid_t pid) {
163 LIST_FOREACH(by_unit, b, first) {
166 if ((r = cgroup_bonding_install(b, pid)) < 0)
173 int cgroup_bonding_kill(CGroupBonding *b, int sig) {
185 if (!(s = set_new(trivial_hash_func, trivial_compare_func)))
188 log_debug("Killing processes from process group %s:%s", b->controller, b->path);
196 if ((r = cgroup_get_task_begin(b->path, b->controller, &iterator, &pid)) != 0) {
201 r = translate_error(r, errno);
207 if (set_get(s, INT_TO_PTR(pid)) != INT_TO_PTR(pid)) {
209 /* If we haven't killed this process
212 if (kill(pid, sig) < 0 && errno != ESRCH) {
220 if ((r = set_put(s, INT_TO_PTR(pid))) < 0)
224 if ((r = cgroup_get_task_next(&iterator, &pid)) != 0) {
229 r = translate_error(r, errno);
236 assert_se(cgroup_get_task_end(&iterator) == 0);
238 /* To avoid racing against processes which fork
239 * quicker than we can kill them we repeat this until
240 * no new pids need to be killed. */
242 } while (!done && r >= 0);
249 return killed ? 0 : -ESRCH;
252 int cgroup_bonding_kill_list(CGroupBonding *first, int sig) {
256 LIST_FOREACH(by_unit, b, first) {
257 if ((r = cgroup_bonding_kill(b, sig)) < 0) {
258 if (r == -EAGAIN || -ESRCH)
270 /* Returns 1 if the group is empty, 0 if it is not, -EAGAIN if we
272 int cgroup_bonding_is_empty(CGroupBonding *b) {
279 r = cgroup_get_task_begin(b->path, b->controller, &iterator, &pid);
281 if (r == 0 || r == ECGEOF)
282 cgroup_get_task_end(&iterator);
284 /* Hmm, no PID in this group? Then it is definitely empty */
288 /* Some error? Let's return it */
290 return translate_error(r, errno);
292 /* It's not empty, and we are the only user, then it is
293 * definitely not empty */
297 /* There are PIDs in the group but we aren't the only users,
298 * hence we cannot say */
302 int cgroup_bonding_is_empty_list(CGroupBonding *first) {
305 LIST_FOREACH(by_unit, b, first) {
308 if ((r = cgroup_bonding_is_empty(b)) < 0) {
309 /* If this returned -EAGAIN, then we don't know if the
310 * group is empty, so let's see if another group can
322 static int install_release_agent(Manager *m, const char *mount_point) {
329 if (asprintf(&p, "%s/release_agent", mount_point) < 0)
332 if ((r = read_one_line_file(p, &c)) < 0) {
340 if ((r = write_one_line_file(p, CGROUP_AGENT_PATH "\n" )) < 0) {
345 } else if (!streq(sc, CGROUP_AGENT_PATH)) {
354 if (asprintf(&p, "%s/notify_on_release", mount_point) < 0)
357 if ((r = read_one_line_file(p, &c)) < 0) {
364 if (streq(sc, "0")) {
365 if ((r = write_one_line_file(p, "1\n")) < 0) {
370 } else if (!streq(sc, "1")) {
382 static int create_hierarchy_cgroup(Manager *m) {
388 if (!(cg = cgroup_new_cgroup(m->cgroup_hierarchy)))
391 if (!(cgroup_add_controller(cg, m->cgroup_controller))) {
396 if ((r = cgroup_create_cgroup(cg, true)) != 0) {
397 log_error("Failed to create cgroup hierarchy group: %s", cgroup_strerror(r));
398 r = translate_error(r, errno);
402 if ((r = cgroup_attach_task(cg)) != 0) {
403 log_error("Failed to add ourselves to hierarchy group: %s", cgroup_strerror(r));
404 r = translate_error(r, errno);
415 int manager_setup_cgroup(Manager *m) {
422 if ((r = cgroup_init()) != 0) {
423 log_error("Failed to initialize libcg: %s", cgroup_strerror(r));
424 return translate_error(r, errno);
427 free(m->cgroup_controller);
428 if (!(m->cgroup_controller = strdup("debug")))
431 if ((r = cgroup_get_subsys_mount_point(m->cgroup_controller, &mp)))
432 return translate_error(r, errno);
436 if ((r = cgroup_get_current_controller_path(pid, m->cgroup_controller, &cp))) {
438 return translate_error(r, errno);
441 free(m->cgroup_hierarchy);
442 m->cgroup_hierarchy = NULL;
443 if (asprintf(&m->cgroup_hierarchy, "%s/systemd-%llu", strcmp(cp, "/") == 0 ? "" : cp, (unsigned long long) pid) < 0) {
449 log_info("Using cgroup controller <%s>, hierarchy mounted at <%s>, using root group <%s>.",
450 m->cgroup_controller,
452 m->cgroup_hierarchy);
454 if ((r = install_release_agent(m, mp)) < 0)
455 log_warning("Failed to install release agent, ignoring: %s", strerror(-r));
457 log_info("Installed release agent, or already installed.");
462 if ((r = create_hierarchy_cgroup(m)) < 0)
463 log_error("Failed to create root cgroup hierarchy: %s", strerror(-r));
465 log_info("Created root group.");
470 int manager_shutdown_cgroup(Manager *m) {
476 if (!m->cgroup_hierarchy)
479 if (!(cg = cgroup_new_cgroup(m->cgroup_hierarchy)))
482 if (!(cgroup_add_controller(cg, m->cgroup_controller))) {
487 if ((r = cgroup_delete_cgroup_ext(cg, CGFLAG_DELETE_IGNORE_MIGRATION|CGFLAG_DELETE_RECURSIVE)) != 0) {
488 log_error("Failed to delete cgroup hierarchy group: %s", cgroup_strerror(r));
489 r = translate_error(r, errno);
500 int cgroup_notify_empty(Manager *m, const char *group) {
501 CGroupBonding *l, *b;
506 if (!(l = hashmap_get(m->cgroup_bondings, group)))
509 LIST_FOREACH(by_path, b, l) {
515 if ((t = cgroup_bonding_is_empty_list(b)) < 0) {
517 /* If we don't know, we don't know */
519 log_warning("Failed to check whether cgroup is empty: %s", strerror(errno));
525 if (UNIT_VTABLE(b->unit)->cgroup_notify_empty)
526 UNIT_VTABLE(b->unit)->cgroup_notify_empty(b->unit);
532 CGroupBonding *cgroup_bonding_find_list(CGroupBonding *first, const char *controller) {
537 LIST_FOREACH(by_unit, b, first)
538 if (streq(b->controller, controller))