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)