+++ /dev/null
-/*-*- Mode: C; c-basic-offset: 8 -*-*/
-
-/***
- This file is part of systemd.
-
- Copyright 2010 Lennart Poettering
-
- systemd is free software; you can redistribute it and/or modify it
- under the terms of the GNU General Public License as published by
- the Free Software Foundation; either version 2 of the License, or
- (at your option) any later version.
-
- systemd is distributed in the hope that it will be useful, but
- WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- General Public License for more details.
-
- You should have received a copy of the GNU General Public License
- along with systemd; If not, see <http://www.gnu.org/licenses/>.
-***/
-
-#include <errno.h>
-#include <assert.h>
-#include <unistd.h>
-#include <sys/types.h>
-#include <signal.h>
-#include <sys/mount.h>
-
-#include "cgroup.h"
-#include "log.h"
-
-static int translate_error(int error, int _errno) {
-
- switch (error) {
-
- case ECGROUPNOTCOMPILED:
- case ECGROUPNOTMOUNTED:
- case ECGROUPNOTEXIST:
- case ECGROUPNOTCREATED:
- return -ENOENT;
-
- case ECGINVAL:
- return -EINVAL;
-
- case ECGROUPNOTALLOWED:
- return -EPERM;
-
- case ECGOTHER:
- return -_errno;
- }
-
- return -EIO;
-}
-
-int cgroup_bonding_realize(CGroupBonding *b) {
- int r;
-
- assert(b);
- assert(b->path);
- assert(b->controller);
-
- if (b->cgroup)
- return 0;
-
- if (!(b->cgroup = cgroup_new_cgroup(b->path)))
- return -ENOMEM;
-
- if (!cgroup_add_controller(b->cgroup, b->controller)) {
- r = -ENOMEM;
- goto fail;
- }
-
- if (b->inherit)
- r = cgroup_create_cgroup_from_parent(b->cgroup, true);
- else
- r = cgroup_create_cgroup(b->cgroup, true);
-
- if (r != 0) {
- r = translate_error(r, errno);
- goto fail;
- }
-
- return 0;
-
-fail:
- cgroup_free(&b->cgroup);
- b->cgroup = NULL;
- return r;
-}
-
-int cgroup_bonding_realize_list(CGroupBonding *first) {
- CGroupBonding *b;
-
- LIST_FOREACH(by_unit, b, first) {
- int r;
-
- if ((r = cgroup_bonding_realize(b)) < 0)
- return r;
- }
-
- return 0;
-}
-
-void cgroup_bonding_free(CGroupBonding *b) {
- assert(b);
-
- if (b->unit) {
- CGroupBonding *f;
-
- LIST_REMOVE(CGroupBonding, by_unit, b->unit->meta.cgroup_bondings, b);
-
- assert_se(f = hashmap_get(b->unit->meta.manager->cgroup_bondings, b->path));
- LIST_REMOVE(CGroupBonding, by_path, f, b);
-
- if (f)
- hashmap_replace(b->unit->meta.manager->cgroup_bondings, b->path, f);
- else
- hashmap_remove(b->unit->meta.manager->cgroup_bondings, b->path);
- }
-
- if (b->cgroup) {
- if (b->only_us && b->clean_up && cgroup_bonding_is_empty(b) > 0)
- cgroup_delete_cgroup_ext(b->cgroup, true);
-
- cgroup_free(&b->cgroup);
- }
-
- free(b->controller);
- free(b->path);
- free(b);
-}
-
-void cgroup_bonding_free_list(CGroupBonding *first) {
- CGroupBonding *b, *n;
-
- LIST_FOREACH_SAFE(by_unit, b, n, first)
- cgroup_bonding_free(b);
-}
-
-int cgroup_bonding_install(CGroupBonding *b, pid_t pid) {
- int r;
-
- assert(b);
- assert(pid >= 0);
-
- if (pid == 0)
- pid = getpid();
-
- if (!b->cgroup)
- return -ENOENT;
-
- if ((r = cgroup_attach_task_pid(b->cgroup, pid)))
- return translate_error(r, errno);
-
- return 0;
-}
-
-int cgroup_bonding_install_list(CGroupBonding *first, pid_t pid) {
- CGroupBonding *b;
-
- LIST_FOREACH(by_unit, b, first) {
- int r;
-
- if ((r = cgroup_bonding_install(b, pid)) < 0)
- return r;
- }
-
- return 0;
-}
-
-int cgroup_bonding_kill(CGroupBonding *b, int sig) {
- int r;
- Set *s;
- bool done;
- bool killed = false;
-
- assert(b);
- assert(sig > 0);
-
- if (!b->only_us)
- return -EAGAIN;
-
- if (!(s = set_new(trivial_hash_func, trivial_compare_func)))
- return -ENOMEM;
-
- do {
- void *iterator;
- pid_t pid;
-
- done = true;
-
- if ((r = cgroup_get_task_begin(b->path, b->controller, &iterator, &pid)) != 0) {
- if (r == ECGEOF) {
- r = 0;
- goto kill_done;
- } else {
- r = translate_error(r, errno);
- break;
- }
- }
-
- for (;;) {
- if (set_get(s, INT_TO_PTR(pid)) != INT_TO_PTR(pid)) {
-
- /* If we haven't killed this process
- * yet, kill it */
-
- if (kill(pid, sig) < 0 && errno != ESRCH) {
- r = -errno;
- break;
- }
-
- killed = true;
- done = false;
-
- if ((r = set_put(s, INT_TO_PTR(pid))) < 0)
- break;
- }
-
- if ((r = cgroup_get_task_next(&iterator, &pid)) != 0) {
-
- if (r == ECGEOF)
- r = 0;
- else
- r = translate_error(r, errno);
-
- break;
- }
- }
-
- kill_done:
- assert_se(cgroup_get_task_end(&iterator) == 0);
-
- /* To avoid racing against processes which fork
- * quicker than we can kill them we repeat this until
- * no new pids need to be killed. */
-
- } while (!done && r >= 0);
-
- set_free(s);
-
- if (r < 0)
- return r;
-
- return killed ? 0 : -ESRCH;
-}
-
-int cgroup_bonding_kill_list(CGroupBonding *first, int sig) {
- CGroupBonding *b;
- int r = -EAGAIN;
-
- LIST_FOREACH(by_unit, b, first) {
- if ((r = cgroup_bonding_kill(b, sig)) < 0) {
- if (r == -EAGAIN || -ESRCH)
- continue;
-
- return r;
- }
-
- return 0;
- }
-
- return r;
-}
-
-/* Returns 1 if the group is empty, 0 if it is not, -EAGAIN if we
- * cannot know */
-int cgroup_bonding_is_empty(CGroupBonding *b) {
- void *iterator;
- pid_t pid;
- int r;
-
- assert(b);
-
- r = cgroup_get_task_begin(b->path, b->controller, &iterator, &pid);
-
- if (r == 0 || r == ECGEOF)
- cgroup_get_task_end(&iterator);
-
- /* Hmm, no PID in this group? Then it is definitely empty */
- if (r == ECGEOF)
- return 1;
-
- /* Some error? Let's return it */
- if (r != 0)
- return translate_error(r, errno);
-
- /* It's not empty, and we are the only user, then it is
- * definitely not empty */
- if (b->only_us)
- return 0;
-
- /* There are PIDs in the group but we aren't the only users,
- * hence we cannot say */
- return -EAGAIN;
-}
-
-int cgroup_bonding_is_empty_list(CGroupBonding *first) {
- CGroupBonding *b;
-
- LIST_FOREACH(by_unit, b, first) {
- int r;
-
- if ((r = cgroup_bonding_is_empty(b)) < 0) {
- /* If this returned -EAGAIN, then we don't know if the
- * group is empty, so let's see if another group can
- * tell us */
-
- if (r != -EAGAIN)
- return r;
- } else
- return r;
- }
-
- return -EAGAIN;
-}
-
-static int install_release_agent(Manager *m, const char *mount_point) {
- char *p, *c, *sc;
- int r;
-
- assert(m);
- assert(mount_point);
-
- if (asprintf(&p, "%s/release_agent", mount_point) < 0)
- return -ENOMEM;
-
- if ((r = read_one_line_file(p, &c)) < 0) {
- free(p);
- return r;
- }
-
- sc = strstrip(c);
-
- if (sc[0] == 0) {
- if ((r = write_one_line_file(p, CGROUP_AGENT_PATH "\n" )) < 0) {
- free(p);
- free(c);
- return r;
- }
- } else if (!streq(sc, CGROUP_AGENT_PATH)) {
- free(p);
- free(c);
- return -EEXIST;
- }
-
- free(c);
- free(p);
-
- if (asprintf(&p, "%s/notify_on_release", mount_point) < 0)
- return -ENOMEM;
-
- if ((r = read_one_line_file(p, &c)) < 0) {
- free(p);
- return r;
- }
-
- sc = strstrip(c);
-
- if (streq(sc, "0")) {
- if ((r = write_one_line_file(p, "1\n")) < 0) {
- free(p);
- free(c);
- return r;
- }
- } else if (!streq(sc, "1")) {
- free(p);
- free(c);
- return -EIO;
- }
-
- free(p);
- free(c);
-
- return 0;
-}
-
-static int create_hierarchy_cgroup(Manager *m) {
- struct cgroup *cg;
- int r;
-
- assert(m);
-
- if (!(cg = cgroup_new_cgroup(m->cgroup_hierarchy)))
- return -ENOMEM;
-
- if (!(cgroup_add_controller(cg, m->cgroup_controller))) {
- r = -ENOMEM;
- goto finish;
- }
-
- if ((r = cgroup_create_cgroup(cg, true)) != 0) {
- log_error("Failed to create cgroup hierarchy group: %s", cgroup_strerror(r));
- r = translate_error(r, errno);
- goto finish;
- }
-
- if ((r = cgroup_attach_task(cg)) != 0) {
- log_error("Failed to add ourselves to hierarchy group: %s", cgroup_strerror(r));
- r = translate_error(r, errno);
- goto finish;
- }
-
- r = 0;
-
-finish:
- cgroup_free(&cg);
- return r;
-}
-
-int manager_setup_cgroup(Manager *m) {
- char *mp, *cp;
- int r;
- pid_t pid;
- char suffix[32];
-
- assert(m);
-
- if ((r = cgroup_init()) != 0) {
- log_error("Failed to initialize libcg: %s", cgroup_strerror(r));
- return translate_error(r, errno);
- }
-
- free(m->cgroup_controller);
- if (!(m->cgroup_controller = strdup("debug")))
- return -ENOMEM;
-
- if ((r = cgroup_get_subsys_mount_point(m->cgroup_controller, &mp)))
- return translate_error(r, errno);
-
- pid = getpid();
-
- if ((r = cgroup_get_current_controller_path(pid, m->cgroup_controller, &cp))) {
- free(mp);
- return translate_error(r, errno);
- }
-
- snprintf(suffix, sizeof(suffix), "/systemd-%u", (unsigned) pid);
- char_array_0(suffix);
-
- free(m->cgroup_hierarchy);
-
- if (endswith(cp, suffix))
- /* We probably got reexecuted and can continue to use our root cgroup */
- m->cgroup_hierarchy = cp;
- else {
- /* We need a new root cgroup */
-
- m->cgroup_hierarchy = NULL;
- r = asprintf(&m->cgroup_hierarchy, "%s%s", streq(cp, "/") ? "" : cp, suffix);
- free(cp);
-
- if (r < 0) {
- free(mp);
- return -ENOMEM;
- }
- }
-
- log_debug("Using cgroup controller <%s>, hierarchy mounted at <%s>, using root group <%s>.",
- m->cgroup_controller,
- mp,
- m->cgroup_hierarchy);
-
- if ((r = install_release_agent(m, mp)) < 0)
- log_warning("Failed to install release agent, ignoring: %s", strerror(-r));
- else
- log_debug("Installed release agent, or already installed.");
-
- free(mp);
-
- if ((r = create_hierarchy_cgroup(m)) < 0)
- log_error("Failed to create root cgroup hierarchy: %s", strerror(-r));
- else
- log_debug("Created root group.");
-
- return r;
-}
-
-int manager_shutdown_cgroup(Manager *m, bool delete) {
- struct cgroup *cg;
- int r;
-
- assert(m);
-
- if (!m->cgroup_hierarchy)
- return 0;
-
- if (!(cg = cgroup_new_cgroup(m->cgroup_hierarchy)))
- return -ENOMEM;
-
- if (!(cgroup_add_controller(cg, m->cgroup_controller))) {
- r = -ENOMEM;
- goto finish;
- }
-
- /* Often enough we won't be able to delete the cgroup we
- * ourselves are in, hence ignore all errors here */
- if (delete)
- cgroup_delete_cgroup_ext(cg, CGFLAG_DELETE_IGNORE_MIGRATION|CGFLAG_DELETE_RECURSIVE);
- r = 0;
-
-finish:
- cgroup_free(&cg);
- return r;
-
-}
-
-int cgroup_notify_empty(Manager *m, const char *group) {
- CGroupBonding *l, *b;
-
- assert(m);
- assert(group);
-
- if (!(l = hashmap_get(m->cgroup_bondings, group)))
- return 0;
-
- LIST_FOREACH(by_path, b, l) {
- int t;
-
- if (!b->unit)
- continue;
-
- if ((t = cgroup_bonding_is_empty_list(b)) < 0) {
-
- /* If we don't know, we don't know */
- if (t != -EAGAIN)
- log_warning("Failed to check whether cgroup is empty: %s", strerror(errno));
-
- continue;
- }
-
- if (t > 0)
- if (UNIT_VTABLE(b->unit)->cgroup_notify_empty)
- UNIT_VTABLE(b->unit)->cgroup_notify_empty(b->unit);
- }
-
- return 0;
-}
-
-CGroupBonding *cgroup_bonding_find_list(CGroupBonding *first, const char *controller) {
- CGroupBonding *b;
-
- assert(controller);
-
- LIST_FOREACH(by_unit, b, first)
- if (streq(b->controller, controller))
- return b;
-
- return NULL;
-}
-
-char *cgroup_bonding_to_string(CGroupBonding *b) {
- char *r;
-
- assert(b);
-
- if (asprintf(&r, "%s:%s", b->controller, b->path) < 0)
- return NULL;
-
- return r;
-}
~ianmdlvl / elogind.git / blobdiff