| /*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/ |
| |
| /*** |
| 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 Lesser General Public License as published by |
| the Free Software Foundation; either version 2.1 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 |
| Lesser General Public License for more details. |
| |
| You should have received a copy of the GNU Lesser 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 <fcntl.h> |
| |
| #include "cgroup.h" |
| #include "cgroup-util.h" |
| #include "log.h" |
| #include "strv.h" |
| #include "path-util.h" |
| |
| int cgroup_bonding_realize(CGroupBonding *b) { |
| int r; |
| |
| assert(b); |
| assert(b->path); |
| assert(b->controller); |
| |
| r = cg_create(b->controller, b->path); |
| if (r < 0) { |
| log_warning("Failed to create cgroup %s:%s: %s", b->controller, b->path, strerror(-r)); |
| return r; |
| } |
| |
| b->realized = true; |
| |
| return 0; |
| } |
| |
| int cgroup_bonding_realize_list(CGroupBonding *first) { |
| CGroupBonding *b; |
| int r; |
| |
| LIST_FOREACH(by_unit, b, first) |
| if ((r = cgroup_bonding_realize(b)) < 0 && b->essential) |
| return r; |
| |
| return 0; |
| } |
| |
| void cgroup_bonding_free(CGroupBonding *b, bool trim) { |
| assert(b); |
| |
| if (b->unit) { |
| CGroupBonding *f; |
| |
| LIST_REMOVE(CGroupBonding, by_unit, b->unit->cgroup_bondings, b); |
| |
| if (streq(b->controller, SYSTEMD_CGROUP_CONTROLLER)) { |
| assert_se(f = hashmap_get(b->unit->manager->cgroup_bondings, b->path)); |
| LIST_REMOVE(CGroupBonding, by_path, f, b); |
| |
| if (f) |
| hashmap_replace(b->unit->manager->cgroup_bondings, b->path, f); |
| else |
| hashmap_remove(b->unit->manager->cgroup_bondings, b->path); |
| } |
| } |
| |
| if (b->realized && b->ours && trim) |
| cg_trim(b->controller, b->path, false); |
| |
| free(b->controller); |
| free(b->path); |
| free(b); |
| } |
| |
| void cgroup_bonding_free_list(CGroupBonding *first, bool remove_or_trim) { |
| CGroupBonding *b, *n; |
| |
| LIST_FOREACH_SAFE(by_unit, b, n, first) |
| cgroup_bonding_free(b, remove_or_trim); |
| } |
| |
| void cgroup_bonding_trim(CGroupBonding *b, bool delete_root) { |
| assert(b); |
| |
| if (b->realized && b->ours) |
| cg_trim(b->controller, b->path, delete_root); |
| } |
| |
| void cgroup_bonding_trim_list(CGroupBonding *first, bool delete_root) { |
| CGroupBonding *b; |
| |
| LIST_FOREACH(by_unit, b, first) |
| cgroup_bonding_trim(b, delete_root); |
| } |
| |
| |
| int cgroup_bonding_install(CGroupBonding *b, pid_t pid, const char *cgroup_suffix) { |
| char *p = NULL; |
| const char *path; |
| int r; |
| |
| assert(b); |
| assert(pid >= 0); |
| |
| if (cgroup_suffix) { |
| p = strjoin(b->path, "/", cgroup_suffix, NULL); |
| if (!p) |
| return -ENOMEM; |
| |
| path = p; |
| } else |
| path = b->path; |
| |
| r = cg_create_and_attach(b->controller, path, pid); |
| free(p); |
| |
| if (r < 0) |
| return r; |
| |
| b->realized = true; |
| return 0; |
| } |
| |
| int cgroup_bonding_install_list(CGroupBonding *first, pid_t pid, const char *cgroup_suffix) { |
| CGroupBonding *b; |
| int r; |
| |
| LIST_FOREACH(by_unit, b, first) { |
| r = cgroup_bonding_install(b, pid, cgroup_suffix); |
| if (r < 0 && b->essential) |
| return r; |
| } |
| |
| return 0; |
| } |
| |
| int cgroup_bonding_set_group_access(CGroupBonding *b, mode_t mode, uid_t uid, gid_t gid) { |
| assert(b); |
| |
| if (!b->realized) |
| return -EINVAL; |
| |
| return cg_set_group_access(b->controller, b->path, mode, uid, gid); |
| } |
| |
| int cgroup_bonding_set_group_access_list(CGroupBonding *first, mode_t mode, uid_t uid, gid_t gid) { |
| CGroupBonding *b; |
| int r; |
| |
| LIST_FOREACH(by_unit, b, first) { |
| r = cgroup_bonding_set_group_access(b, mode, uid, gid); |
| if (r < 0) |
| return r; |
| } |
| |
| return 0; |
| } |
| |
| int cgroup_bonding_set_task_access(CGroupBonding *b, mode_t mode, uid_t uid, gid_t gid, int sticky) { |
| assert(b); |
| |
| if (!b->realized) |
| return -EINVAL; |
| |
| return cg_set_task_access(b->controller, b->path, mode, uid, gid, sticky); |
| } |
| |
| int cgroup_bonding_set_task_access_list(CGroupBonding *first, mode_t mode, uid_t uid, gid_t gid, int sticky) { |
| CGroupBonding *b; |
| int r; |
| |
| LIST_FOREACH(by_unit, b, first) { |
| r = cgroup_bonding_set_task_access(b, mode, uid, gid, sticky); |
| if (r < 0) |
| return r; |
| } |
| |
| return 0; |
| } |
| |
| int cgroup_bonding_kill(CGroupBonding *b, int sig, bool sigcont, bool rem, Set *s, const char *cgroup_suffix) { |
| char *p = NULL; |
| const char *path; |
| int r; |
| |
| assert(b); |
| assert(sig >= 0); |
| |
| /* Don't kill cgroups that aren't ours */ |
| if (!b->ours) |
| return 0; |
| |
| if (cgroup_suffix) { |
| p = strjoin(b->path, "/", cgroup_suffix, NULL); |
| if (!p) |
| return -ENOMEM; |
| |
| path = p; |
| } else |
| path = b->path; |
| |
| r = cg_kill_recursive(b->controller, path, sig, sigcont, true, rem, s); |
| free(p); |
| |
| return r; |
| } |
| |
| int cgroup_bonding_kill_list(CGroupBonding *first, int sig, bool sigcont, bool rem, Set *s, const char *cgroup_suffix) { |
| CGroupBonding *b; |
| Set *allocated_set = NULL; |
| int ret = -EAGAIN, r; |
| |
| if (!first) |
| return 0; |
| |
| if (!s) |
| if (!(s = allocated_set = set_new(trivial_hash_func, trivial_compare_func))) |
| return -ENOMEM; |
| |
| LIST_FOREACH(by_unit, b, first) { |
| r = cgroup_bonding_kill(b, sig, sigcont, rem, s, cgroup_suffix); |
| if (r < 0) { |
| if (r == -EAGAIN || r == -ESRCH) |
| continue; |
| |
| ret = r; |
| goto finish; |
| } |
| |
| if (ret < 0 || r > 0) |
| ret = r; |
| } |
| |
| finish: |
| if (allocated_set) |
| set_free(allocated_set); |
| |
| return ret; |
| } |
| |
| /* Returns 1 if the group is empty, 0 if it is not, -EAGAIN if we |
| * cannot know */ |
| int cgroup_bonding_is_empty(CGroupBonding *b) { |
| int r; |
| |
| assert(b); |
| |
| if ((r = cg_is_empty_recursive(b->controller, b->path, true)) < 0) |
| return r; |
| |
| /* If it is empty it is empty */ |
| if (r > 0) |
| return 1; |
| |
| /* It's not only us using this cgroup, so we just don't know */ |
| return b->ours ? 0 : -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; |
| } |
| |
| int manager_setup_cgroup(Manager *m) { |
| char *current = NULL, *path = NULL; |
| int r; |
| char suffix[32]; |
| |
| assert(m); |
| |
| /* 0. Be nice to Ingo Molnar #628004 */ |
| if (path_is_mount_point("/sys/fs/cgroup/systemd", false) <= 0) { |
| log_warning("No control group support available, not creating root group."); |
| return 0; |
| } |
| |
| /* 1. Determine hierarchy */ |
| r = cg_get_by_pid(SYSTEMD_CGROUP_CONTROLLER, 0, ¤t); |
| if (r < 0) { |
| log_error("Cannot determine cgroup we are running in: %s", strerror(-r)); |
| goto finish; |
| } |
| |
| if (m->running_as == MANAGER_SYSTEM) |
| strcpy(suffix, "/system"); |
| else { |
| snprintf(suffix, sizeof(suffix), "/systemd-%lu", (unsigned long) getpid()); |
| char_array_0(suffix); |
| } |
| |
| free(m->cgroup_hierarchy); |
| if (endswith(current, suffix)) { |
| /* We probably got reexecuted and can continue to use our root cgroup */ |
| m->cgroup_hierarchy = current; |
| current = NULL; |
| |
| } else { |
| /* We need a new root cgroup */ |
| m->cgroup_hierarchy = NULL; |
| if (asprintf(&m->cgroup_hierarchy, "%s%s", streq(current, "/") ? "" : current, suffix) < 0) { |
| r = log_oom(); |
| goto finish; |
| } |
| } |
| |
| /* 2. Show data */ |
| r = cg_get_path(SYSTEMD_CGROUP_CONTROLLER, m->cgroup_hierarchy, NULL, &path); |
| if (r < 0) { |
| log_error("Cannot find cgroup mount point: %s", strerror(-r)); |
| goto finish; |
| } |
| |
| log_debug("Using cgroup controller " SYSTEMD_CGROUP_CONTROLLER ". File system hierarchy is at %s.", path); |
| |
| /* 3. Install agent */ |
| r = cg_install_release_agent(SYSTEMD_CGROUP_CONTROLLER, SYSTEMD_CGROUP_AGENT_PATH); |
| if (r < 0) |
| log_warning("Failed to install release agent, ignoring: %s", strerror(-r)); |
| else if (r > 0) |
| log_debug("Installed release agent."); |
| else |
| log_debug("Release agent already installed."); |
| |
| /* 4. Realize the group */ |
| r = cg_create_and_attach(SYSTEMD_CGROUP_CONTROLLER, m->cgroup_hierarchy, 0); |
| if (r < 0) { |
| log_error("Failed to create root cgroup hierarchy: %s", strerror(-r)); |
| goto finish; |
| } |
| |
| /* 5. And pin it, so that it cannot be unmounted */ |
| if (m->pin_cgroupfs_fd >= 0) |
| close_nointr_nofail(m->pin_cgroupfs_fd); |
| |
| m->pin_cgroupfs_fd = open(path, O_RDONLY|O_CLOEXEC|O_DIRECTORY|O_NOCTTY|O_NONBLOCK); |
| if (r < 0) { |
| log_error("Failed to open pin file: %m"); |
| r = -errno; |
| goto finish; |
| } |
| |
| log_debug("Created root group."); |
| |
| cg_shorten_controllers(m->default_controllers); |
| |
| finish: |
| free(current); |
| free(path); |
| |
| return r; |
| } |
| |
| void manager_shutdown_cgroup(Manager *m, bool delete) { |
| assert(m); |
| |
| if (delete && m->cgroup_hierarchy) |
| cg_delete(SYSTEMD_CGROUP_CONTROLLER, m->cgroup_hierarchy); |
| |
| if (m->pin_cgroupfs_fd >= 0) { |
| close_nointr_nofail(m->pin_cgroupfs_fd); |
| m->pin_cgroupfs_fd = -1; |
| } |
| |
| free(m->cgroup_hierarchy); |
| m->cgroup_hierarchy = NULL; |
| } |
| |
| int cgroup_bonding_get(Manager *m, const char *cgroup, CGroupBonding **bonding) { |
| CGroupBonding *b; |
| char *p; |
| |
| assert(m); |
| assert(cgroup); |
| assert(bonding); |
| |
| b = hashmap_get(m->cgroup_bondings, cgroup); |
| if (b) { |
| *bonding = b; |
| return 1; |
| } |
| |
| p = strdup(cgroup); |
| if (!p) |
| return -ENOMEM; |
| |
| for (;;) { |
| char *e; |
| |
| e = strrchr(p, '/'); |
| if (!e || e == p) { |
| free(p); |
| *bonding = NULL; |
| return 0; |
| } |
| |
| *e = 0; |
| |
| b = hashmap_get(m->cgroup_bondings, p); |
| if (b) { |
| free(p); |
| *bonding = b; |
| return 1; |
| } |
| } |
| } |
| |
| int cgroup_notify_empty(Manager *m, const char *group) { |
| CGroupBonding *l, *b; |
| int r; |
| |
| assert(m); |
| assert(group); |
| |
| r = cgroup_bonding_get(m, group, &l); |
| if (r <= 0) |
| return r; |
| |
| LIST_FOREACH(by_path, b, l) { |
| int t; |
| |
| if (!b->unit) |
| continue; |
| |
| t = cgroup_bonding_is_empty_list(b); |
| if (t < 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 it is empty, let's delete it */ |
| cgroup_bonding_trim_list(b->unit->cgroup_bondings, true); |
| |
| if (UNIT_VTABLE(b->unit)->cgroup_notify_empty) |
| UNIT_VTABLE(b->unit)->cgroup_notify_empty(b->unit); |
| } |
| } |
| |
| return 0; |
| } |
| |
| Unit* cgroup_unit_by_pid(Manager *m, pid_t pid) { |
| CGroupBonding *l, *b; |
| char *group = NULL; |
| |
| assert(m); |
| |
| if (pid <= 1) |
| return NULL; |
| |
| if (cg_get_by_pid(SYSTEMD_CGROUP_CONTROLLER, pid, &group) < 0) |
| return NULL; |
| |
| l = hashmap_get(m->cgroup_bondings, group); |
| |
| if (!l) { |
| char *slash; |
| |
| while ((slash = strrchr(group, '/'))) { |
| if (slash == group) |
| break; |
| |
| *slash = 0; |
| |
| if ((l = hashmap_get(m->cgroup_bondings, group))) |
| break; |
| } |
| } |
| |
| free(group); |
| |
| LIST_FOREACH(by_path, b, l) { |
| |
| if (!b->unit) |
| continue; |
| |
| if (b->ours) |
| return b->unit; |
| } |
| |
| return NULL; |
| } |
| |
| 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; |
| } |
| |
| pid_t cgroup_bonding_search_main_pid(CGroupBonding *b) { |
| FILE *f; |
| pid_t pid = 0, npid, mypid; |
| |
| assert(b); |
| |
| if (!b->ours) |
| return 0; |
| |
| if (cg_enumerate_processes(b->controller, b->path, &f) < 0) |
| return 0; |
| |
| mypid = getpid(); |
| |
| while (cg_read_pid(f, &npid) > 0) { |
| pid_t ppid; |
| |
| if (npid == pid) |
| continue; |
| |
| /* Ignore processes that aren't our kids */ |
| if (get_parent_of_pid(npid, &ppid) >= 0 && ppid != mypid) |
| continue; |
| |
| if (pid != 0) { |
| /* Dang, there's more than one daemonized PID |
| in this group, so we don't know what process |
| is the main process. */ |
| pid = 0; |
| break; |
| } |
| |
| pid = npid; |
| } |
| |
| fclose(f); |
| |
| return pid; |
| } |
| |
| pid_t cgroup_bonding_search_main_pid_list(CGroupBonding *first) { |
| CGroupBonding *b; |
| pid_t pid; |
| |
| /* Try to find a main pid from this cgroup, but checking if |
| * there's only one PID in the cgroup and returning it. Later |
| * on we might want to add additional, smarter heuristics |
| * here. */ |
| |
| LIST_FOREACH(by_unit, b, first) |
| if ((pid = cgroup_bonding_search_main_pid(b)) != 0) |
| return pid; |
| |
| return 0; |
| |
| } |