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);
122 if (b->only_us && b->clean_up && cgroup_bonding_is_empty(b) > 0)
123 cgroup_delete_cgroup_ext(b->cgroup, true);
125 cgroup_free(&b->cgroup);
133 void cgroup_bonding_free_list(CGroupBonding *first) {
134 CGroupBonding *b, *n;
136 LIST_FOREACH_SAFE(by_unit, b, n, first)
137 cgroup_bonding_free(b);
140 int cgroup_bonding_install(CGroupBonding *b, pid_t pid) {
152 if ((r = cgroup_attach_task_pid(b->cgroup, pid)))
153 return translate_error(r, errno);
158 int cgroup_bonding_install_list(CGroupBonding *first, pid_t pid) {
161 LIST_FOREACH(by_unit, b, first) {
164 if ((r = cgroup_bonding_install(b, pid)) < 0)
171 int cgroup_bonding_kill(CGroupBonding *b, int sig) {
183 if (!(s = set_new(trivial_hash_func, trivial_compare_func)))
192 if ((r = cgroup_get_task_begin(b->path, b->controller, &iterator, &pid)) != 0) {
197 r = translate_error(r, errno);
203 if (set_get(s, INT_TO_PTR(pid)) != INT_TO_PTR(pid)) {
205 /* If we haven't killed this process
208 if (kill(pid, sig) < 0 && errno != ESRCH) {
216 if ((r = set_put(s, INT_TO_PTR(pid))) < 0)
220 if ((r = cgroup_get_task_next(&iterator, &pid)) != 0) {
225 r = translate_error(r, errno);
232 assert_se(cgroup_get_task_end(&iterator) == 0);
234 /* To avoid racing against processes which fork
235 * quicker than we can kill them we repeat this until
236 * no new pids need to be killed. */
238 } while (!done && r >= 0);
245 return killed ? 0 : -ESRCH;
248 int cgroup_bonding_kill_list(CGroupBonding *first, int sig) {
252 LIST_FOREACH(by_unit, b, first) {
253 if ((r = cgroup_bonding_kill(b, sig)) < 0) {
254 if (r == -EAGAIN || -ESRCH)
266 /* Returns 1 if the group is empty, 0 if it is not, -EAGAIN if we
268 int cgroup_bonding_is_empty(CGroupBonding *b) {
275 r = cgroup_get_task_begin(b->path, b->controller, &iterator, &pid);
277 if (r == 0 || r == ECGEOF)
278 cgroup_get_task_end(&iterator);
280 /* Hmm, no PID in this group? Then it is definitely empty */
284 /* Some error? Let's return it */
286 return translate_error(r, errno);
288 /* It's not empty, and we are the only user, then it is
289 * definitely not empty */
293 /* There are PIDs in the group but we aren't the only users,
294 * hence we cannot say */
298 int cgroup_bonding_is_empty_list(CGroupBonding *first) {
301 LIST_FOREACH(by_unit, b, first) {
304 if ((r = cgroup_bonding_is_empty(b)) < 0) {
305 /* If this returned -EAGAIN, then we don't know if the
306 * group is empty, so let's see if another group can
318 static int install_release_agent(Manager *m, const char *mount_point) {
325 if (asprintf(&p, "%s/release_agent", mount_point) < 0)
328 if ((r = read_one_line_file(p, &c)) < 0) {
336 if ((r = write_one_line_file(p, CGROUP_AGENT_PATH "\n" )) < 0) {
341 } else if (!streq(sc, CGROUP_AGENT_PATH)) {
350 if (asprintf(&p, "%s/notify_on_release", mount_point) < 0)
353 if ((r = read_one_line_file(p, &c)) < 0) {
360 if (streq(sc, "0")) {
361 if ((r = write_one_line_file(p, "1\n")) < 0) {
366 } else if (!streq(sc, "1")) {
378 static int create_hierarchy_cgroup(Manager *m) {
384 if (!(cg = cgroup_new_cgroup(m->cgroup_hierarchy)))
387 if (!(cgroup_add_controller(cg, m->cgroup_controller))) {
392 if ((r = cgroup_create_cgroup(cg, true)) != 0) {
393 log_error("Failed to create cgroup hierarchy group: %s", cgroup_strerror(r));
394 r = translate_error(r, errno);
398 if ((r = cgroup_attach_task(cg)) != 0) {
399 log_error("Failed to add ourselves to hierarchy group: %s", cgroup_strerror(r));
400 r = translate_error(r, errno);
411 int manager_setup_cgroup(Manager *m) {
419 if ((r = cgroup_init()) != 0) {
420 log_error("Failed to initialize libcg: %s", cgroup_strerror(r));
421 return translate_error(r, errno);
424 free(m->cgroup_controller);
425 if (!(m->cgroup_controller = strdup("debug")))
428 if ((r = cgroup_get_subsys_mount_point(m->cgroup_controller, &mp)))
429 return translate_error(r, errno);
433 if ((r = cgroup_get_current_controller_path(pid, m->cgroup_controller, &cp))) {
435 return translate_error(r, errno);
438 snprintf(suffix, sizeof(suffix), "/systemd-%u", (unsigned) pid);
439 char_array_0(suffix);
441 free(m->cgroup_hierarchy);
443 if (endswith(cp, suffix))
444 /* We probably got reexecuted and can continue to use our root cgroup */
445 m->cgroup_hierarchy = cp;
447 /* We need a new root cgroup */
449 m->cgroup_hierarchy = NULL;
450 r = asprintf(&m->cgroup_hierarchy, "%s%s", streq(cp, "/") ? "" : cp, suffix);
459 log_info("Using cgroup controller <%s>, hierarchy mounted at <%s>, using root group <%s>.",
460 m->cgroup_controller,
462 m->cgroup_hierarchy);
464 if ((r = install_release_agent(m, mp)) < 0)
465 log_warning("Failed to install release agent, ignoring: %s", strerror(-r));
467 log_info("Installed release agent, or already installed.");
471 if ((r = create_hierarchy_cgroup(m)) < 0)
472 log_error("Failed to create root cgroup hierarchy: %s", strerror(-r));
474 log_info("Created root group.");
479 int manager_shutdown_cgroup(Manager *m, bool delete) {
485 if (!m->cgroup_hierarchy)
488 if (!(cg = cgroup_new_cgroup(m->cgroup_hierarchy)))
491 if (!(cgroup_add_controller(cg, m->cgroup_controller))) {
496 /* Often enough we won't be able to delete the cgroup we
497 * ourselves are in, hence ignore all errors here */
499 cgroup_delete_cgroup_ext(cg, CGFLAG_DELETE_IGNORE_MIGRATION|CGFLAG_DELETE_RECURSIVE);
508 int cgroup_notify_empty(Manager *m, const char *group) {
509 CGroupBonding *l, *b;
514 if (!(l = hashmap_get(m->cgroup_bondings, group)))
517 LIST_FOREACH(by_path, b, l) {
523 if ((t = cgroup_bonding_is_empty_list(b)) < 0) {
525 /* If we don't know, we don't know */
527 log_warning("Failed to check whether cgroup is empty: %s", strerror(errno));
533 if (UNIT_VTABLE(b->unit)->cgroup_notify_empty)
534 UNIT_VTABLE(b->unit)->cgroup_notify_empty(b->unit);
540 CGroupBonding *cgroup_bonding_find_list(CGroupBonding *first, const char *controller) {
545 LIST_FOREACH(by_unit, b, first)
546 if (streq(b->controller, controller))
552 char *cgroup_bonding_to_string(CGroupBonding *b) {
557 if (asprintf(&r, "%s:%s", b->controller, b->path) < 0)