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
)))
186 log_debug("Killing processes from process group %s:%s", b
->controller
, b
->path
);
194 if ((r
= cgroup_get_task_begin(b
->path
, b
->controller
, &iterator
, &pid
)) != 0) {
199 r
= translate_error(r
, errno
);
205 if (set_get(s
, INT_TO_PTR(pid
)) != INT_TO_PTR(pid
)) {
207 /* If we haven't killed this process
210 if (kill(pid
, sig
) < 0 && errno
!= ESRCH
) {
218 if ((r
= set_put(s
, INT_TO_PTR(pid
))) < 0)
222 if ((r
= cgroup_get_task_next(&iterator
, &pid
)) != 0) {
227 r
= translate_error(r
, errno
);
234 assert_se(cgroup_get_task_end(&iterator
) == 0);
236 /* To avoid racing against processes which fork
237 * quicker than we can kill them we repeat this until
238 * no new pids need to be killed. */
240 } while (!done
&& r
>= 0);
247 return killed
? 0 : -ESRCH
;
250 int cgroup_bonding_kill_list(CGroupBonding
*first
, int sig
) {
254 LIST_FOREACH(by_unit
, b
, first
) {
255 if ((r
= cgroup_bonding_kill(b
, sig
)) < 0) {
256 if (r
== -EAGAIN
|| -ESRCH
)
268 /* Returns 1 if the group is empty, 0 if it is not, -EAGAIN if we
270 int cgroup_bonding_is_empty(CGroupBonding
*b
) {
277 r
= cgroup_get_task_begin(b
->path
, b
->controller
, &iterator
, &pid
);
279 if (r
== 0 || r
== ECGEOF
)
280 cgroup_get_task_end(&iterator
);
282 /* Hmm, no PID in this group? Then it is definitely empty */
286 /* Some error? Let's return it */
288 return translate_error(r
, errno
);
290 /* It's not empty, and we are the only user, then it is
291 * definitely not empty */
295 /* There are PIDs in the group but we aren't the only users,
296 * hence we cannot say */
300 int cgroup_bonding_is_empty_list(CGroupBonding
*first
) {
303 LIST_FOREACH(by_unit
, b
, first
) {
306 if ((r
= cgroup_bonding_is_empty(b
)) < 0) {
307 /* If this returned -EAGAIN, then we don't know if the
308 * group is empty, so let's see if another group can
320 static int install_release_agent(Manager
*m
, const char *mount_point
) {
327 if (asprintf(&p
, "%s/release_agent", mount_point
) < 0)
330 if ((r
= read_one_line_file(p
, &c
)) < 0) {
338 if ((r
= write_one_line_file(p
, CGROUP_AGENT_PATH
"\n" )) < 0) {
343 } else if (!streq(sc
, CGROUP_AGENT_PATH
)) {
352 if (asprintf(&p
, "%s/notify_on_release", mount_point
) < 0)
355 if ((r
= read_one_line_file(p
, &c
)) < 0) {
362 if (streq(sc
, "0")) {
363 if ((r
= write_one_line_file(p
, "1\n")) < 0) {
368 } else if (!streq(sc
, "1")) {
380 static int create_hierarchy_cgroup(Manager
*m
) {
386 if (!(cg
= cgroup_new_cgroup(m
->cgroup_hierarchy
)))
389 if (!(cgroup_add_controller(cg
, m
->cgroup_controller
))) {
394 if ((r
= cgroup_create_cgroup(cg
, true)) != 0) {
395 log_error("Failed to create cgroup hierarchy group: %s", cgroup_strerror(r
));
396 r
= translate_error(r
, errno
);
400 if ((r
= cgroup_attach_task(cg
)) != 0) {
401 log_error("Failed to add ourselves to hierarchy group: %s", cgroup_strerror(r
));
402 r
= translate_error(r
, errno
);
413 int manager_setup_cgroup(Manager
*m
) {
421 if ((r
= cgroup_init()) != 0) {
422 log_error("Failed to initialize libcg: %s", cgroup_strerror(r
));
423 return translate_error(r
, errno
);
426 free(m
->cgroup_controller
);
427 if (!(m
->cgroup_controller
= strdup("debug")))
430 if ((r
= cgroup_get_subsys_mount_point(m
->cgroup_controller
, &mp
)))
431 return translate_error(r
, errno
);
435 if ((r
= cgroup_get_current_controller_path(pid
, m
->cgroup_controller
, &cp
))) {
437 return translate_error(r
, errno
);
440 snprintf(suffix
, sizeof(suffix
), "/systemd-%u", (unsigned) pid
);
441 char_array_0(suffix
);
443 free(m
->cgroup_hierarchy
);
445 if (endswith(cp
, suffix
))
446 /* We probably got reexecuted and can continue to use our root cgroup */
447 m
->cgroup_hierarchy
= cp
;
449 /* We need a new root cgroup */
451 m
->cgroup_hierarchy
= NULL
;
452 r
= asprintf(&m
->cgroup_hierarchy
, "%s%s", streq(cp
, "/") ? "" : cp
, suffix
);
461 log_info("Using cgroup controller <%s>, hierarchy mounted at <%s>, using root group <%s>.",
462 m
->cgroup_controller
,
464 m
->cgroup_hierarchy
);
466 if ((r
= install_release_agent(m
, mp
)) < 0)
467 log_warning("Failed to install release agent, ignoring: %s", strerror(-r
));
469 log_info("Installed release agent, or already installed.");
473 if ((r
= create_hierarchy_cgroup(m
)) < 0)
474 log_error("Failed to create root cgroup hierarchy: %s", strerror(-r
));
476 log_info("Created root group.");
481 int manager_shutdown_cgroup(Manager
*m
, bool delete) {
487 if (!m
->cgroup_hierarchy
)
490 if (!(cg
= cgroup_new_cgroup(m
->cgroup_hierarchy
)))
493 if (!(cgroup_add_controller(cg
, m
->cgroup_controller
))) {
498 /* Often enough we won't be able to delete the cgroup we
499 * ourselves are in, hence ignore all errors here */
501 cgroup_delete_cgroup_ext(cg
, CGFLAG_DELETE_IGNORE_MIGRATION
|CGFLAG_DELETE_RECURSIVE
);
510 int cgroup_notify_empty(Manager
*m
, const char *group
) {
511 CGroupBonding
*l
, *b
;
516 if (!(l
= hashmap_get(m
->cgroup_bondings
, group
)))
519 LIST_FOREACH(by_path
, b
, l
) {
525 if ((t
= cgroup_bonding_is_empty_list(b
)) < 0) {
527 /* If we don't know, we don't know */
529 log_warning("Failed to check whether cgroup is empty: %s", strerror(errno
));
535 if (UNIT_VTABLE(b
->unit
)->cgroup_notify_empty
)
536 UNIT_VTABLE(b
->unit
)->cgroup_notify_empty(b
->unit
);
542 CGroupBonding
*cgroup_bonding_find_list(CGroupBonding
*first
, const char *controller
) {
547 LIST_FOREACH(by_unit
, b
, first
)
548 if (streq(b
->controller
, controller
))
554 char *cgroup_bonding_to_string(CGroupBonding
*b
) {
559 if (asprintf(&r
, "%s:%s", b
->controller
, b
->path
) < 0)