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-rw-r--r--src/basic/cgroup-util.c378
1 files changed, 252 insertions, 126 deletions
diff --git a/src/basic/cgroup-util.c b/src/basic/cgroup-util.c
index 6948ed3931..bda5c555ad 100644
--- a/src/basic/cgroup-util.c
+++ b/src/basic/cgroup-util.c
@@ -208,6 +208,18 @@ int cg_rmdir(const char *controller, const char *path) {
if (r < 0 && errno != ENOENT)
return -errno;
+ r = cg_hybrid_unified();
+ if (r < 0)
+ return r;
+ if (r == 0)
+ return 0;
+
+ if (streq(controller, SYSTEMD_CGROUP_CONTROLLER)) {
+ r = cg_rmdir(SYSTEMD_CGROUP_CONTROLLER_LEGACY, path);
+ if (r < 0)
+ log_warning_errno(r, "Failed to remove compat systemd cgroup %s: %m", path);
+ }
+
return 0;
}
@@ -542,6 +554,13 @@ static const char *controller_to_dirname(const char *controller) {
* just cuts off the name= prefixed used for named
* hierarchies, if it is specified. */
+ if (streq(controller, SYSTEMD_CGROUP_CONTROLLER)) {
+ if (cg_hybrid_unified() > 0)
+ controller = SYSTEMD_CGROUP_CONTROLLER_HYBRID;
+ else
+ controller = SYSTEMD_CGROUP_CONTROLLER_LEGACY;
+ }
+
e = startswith(controller, "name=");
if (e)
return e;
@@ -594,7 +613,7 @@ static int join_path_unified(const char *path, const char *suffix, char **fs) {
}
int cg_get_path(const char *controller, const char *path, const char *suffix, char **fs) {
- int unified, r;
+ int r;
assert(fs);
@@ -623,11 +642,10 @@ int cg_get_path(const char *controller, const char *path, const char *suffix, ch
if (!cg_controller_is_valid(controller))
return -EINVAL;
- unified = cg_all_unified();
- if (unified < 0)
- return unified;
-
- if (unified > 0)
+ r = cg_all_unified();
+ if (r < 0)
+ return r;
+ if (r > 0)
r = join_path_unified(path, suffix, fs);
else
r = join_path_legacy(controller, path, suffix, fs);
@@ -639,7 +657,7 @@ int cg_get_path(const char *controller, const char *path, const char *suffix, ch
}
static int controller_is_accessible(const char *controller) {
- int unified;
+ int r;
assert(controller);
@@ -651,10 +669,10 @@ static int controller_is_accessible(const char *controller) {
if (!cg_controller_is_valid(controller))
return -EINVAL;
- unified = cg_all_unified();
- if (unified < 0)
- return unified;
- if (unified > 0) {
+ r = cg_all_unified();
+ if (r < 0)
+ return r;
+ if (r > 0) {
/* We don't support named hierarchies if we are using
* the unified hierarchy. */
@@ -708,7 +726,7 @@ static int trim_cb(const char *path, const struct stat *sb, int typeflag, struct
int cg_trim(const char *controller, const char *path, bool delete_root) {
_cleanup_free_ char *fs = NULL;
- int r = 0;
+ int r = 0, q;
assert(path);
@@ -731,6 +749,15 @@ int cg_trim(const char *controller, const char *path, bool delete_root) {
return -errno;
}
+ q = cg_hybrid_unified();
+ if (q < 0)
+ return q;
+ if (q > 0 && streq(controller, SYSTEMD_CGROUP_CONTROLLER)) {
+ q = cg_trim(SYSTEMD_CGROUP_CONTROLLER_LEGACY, path, delete_root);
+ if (q < 0)
+ log_warning_errno(q, "Failed to trim compat systemd cgroup %s: %m", path);
+ }
+
return r;
}
@@ -754,6 +781,16 @@ int cg_create(const char *controller, const char *path) {
return -errno;
}
+ r = cg_hybrid_unified();
+ if (r < 0)
+ return r;
+
+ if (r > 0 && streq(controller, SYSTEMD_CGROUP_CONTROLLER)) {
+ r = cg_create(SYSTEMD_CGROUP_CONTROLLER_LEGACY, path);
+ if (r < 0)
+ log_warning_errno(r, "Failed to create compat systemd cgroup %s: %m", path);
+ }
+
return 1;
}
@@ -791,7 +828,21 @@ int cg_attach(const char *controller, const char *path, pid_t pid) {
xsprintf(c, PID_FMT "\n", pid);
- return write_string_file(fs, c, 0);
+ r = write_string_file(fs, c, 0);
+ if (r < 0)
+ return r;
+
+ r = cg_hybrid_unified();
+ if (r < 0)
+ return r;
+
+ if (r > 0 && streq(controller, SYSTEMD_CGROUP_CONTROLLER)) {
+ r = cg_attach(SYSTEMD_CGROUP_CONTROLLER_LEGACY, path, pid);
+ if (r < 0)
+ log_warning_errno(r, "Failed to attach %d to compat systemd cgroup %s: %m", pid, path);
+ }
+
+ return 0;
}
int cg_attach_fallback(const char *controller, const char *path, pid_t pid) {
@@ -840,7 +891,20 @@ int cg_set_group_access(
if (r < 0)
return r;
- return chmod_and_chown(fs, mode, uid, gid);
+ r = chmod_and_chown(fs, mode, uid, gid);
+ if (r < 0)
+ return r;
+
+ r = cg_hybrid_unified();
+ if (r < 0)
+ return r;
+ if (r > 0 && streq(controller, SYSTEMD_CGROUP_CONTROLLER)) {
+ r = cg_set_group_access(SYSTEMD_CGROUP_CONTROLLER_LEGACY, path, mode, uid, gid);
+ if (r < 0)
+ log_warning_errno(r, "Failed to set group access on compat systemd cgroup %s: %m", path);
+ }
+
+ return 0;
}
int cg_set_task_access(
@@ -851,7 +915,7 @@ int cg_set_task_access(
gid_t gid) {
_cleanup_free_ char *fs = NULL, *procs = NULL;
- int r, unified;
+ int r;
assert(path);
@@ -869,16 +933,24 @@ int cg_set_task_access(
if (r < 0)
return r;
- unified = cg_unified(controller);
- if (unified < 0)
- return unified;
- if (unified)
- return 0;
+ r = cg_unified_controller(controller);
+ if (r < 0)
+ return r;
+ if (r == 0) {
+ /* Compatibility, Always keep values for "tasks" in sync with
+ * "cgroup.procs" */
+ if (cg_get_path(controller, path, "tasks", &procs) >= 0)
+ (void) chmod_and_chown(procs, mode, uid, gid);
+ }
- /* Compatibility, Always keep values for "tasks" in sync with
- * "cgroup.procs" */
- if (cg_get_path(controller, path, "tasks", &procs) >= 0)
- (void) chmod_and_chown(procs, mode, uid, gid);
+ r = cg_hybrid_unified();
+ if (r < 0)
+ return r;
+ if (r > 0 && streq(controller, SYSTEMD_CGROUP_CONTROLLER)) {
+ r = cg_set_task_access(SYSTEMD_CGROUP_CONTROLLER_LEGACY, path, mode, uid, gid);
+ if (r < 0)
+ log_warning_errno(r, "Failed to set task access on compat systemd cgroup %s: %m", path);
+ }
return 0;
}
@@ -923,7 +995,7 @@ int cg_get_xattr(const char *controller, const char *path, const char *name, voi
int cg_pid_get_path(const char *controller, pid_t pid, char **path) {
_cleanup_fclose_ FILE *f = NULL;
char line[LINE_MAX];
- const char *fs;
+ const char *fs, *controller_str;
size_t cs = 0;
int unified;
@@ -936,11 +1008,17 @@ int cg_pid_get_path(const char *controller, pid_t pid, char **path) {
} else
controller = SYSTEMD_CGROUP_CONTROLLER;
- unified = cg_unified(controller);
+ unified = cg_unified_controller(controller);
if (unified < 0)
return unified;
- if (unified == 0)
- cs = strlen(controller);
+ if (unified == 0) {
+ if (streq(controller, SYSTEMD_CGROUP_CONTROLLER))
+ controller_str = SYSTEMD_CGROUP_CONTROLLER_LEGACY;
+ else
+ controller_str = controller;
+
+ cs = strlen(controller_str);
+ }
fs = procfs_file_alloca(pid, "cgroup");
f = fopen(fs, "re");
@@ -977,7 +1055,7 @@ int cg_pid_get_path(const char *controller, pid_t pid, char **path) {
*e = 0;
FOREACH_WORD_SEPARATOR(word, k, l, ",", state) {
- if (k == cs && memcmp(word, controller, cs) == 0) {
+ if (k == cs && memcmp(word, controller_str, cs) == 0) {
found = true;
break;
}
@@ -1001,14 +1079,14 @@ int cg_pid_get_path(const char *controller, pid_t pid, char **path) {
int cg_install_release_agent(const char *controller, const char *agent) {
_cleanup_free_ char *fs = NULL, *contents = NULL;
const char *sc;
- int r, unified;
+ int r;
assert(agent);
- unified = cg_unified(controller);
- if (unified < 0)
- return unified;
- if (unified) /* doesn't apply to unified hierarchy */
+ r = cg_unified_controller(controller);
+ if (r < 0)
+ return r;
+ if (r > 0) /* doesn't apply to unified hierarchy */
return -EOPNOTSUPP;
r = cg_get_path(controller, NULL, "release_agent", &fs);
@@ -1054,12 +1132,12 @@ int cg_install_release_agent(const char *controller, const char *agent) {
int cg_uninstall_release_agent(const char *controller) {
_cleanup_free_ char *fs = NULL;
- int r, unified;
+ int r;
- unified = cg_unified(controller);
- if (unified < 0)
- return unified;
- if (unified) /* Doesn't apply to unified hierarchy */
+ r = cg_unified_controller(controller);
+ if (r < 0)
+ return r;
+ if (r > 0) /* Doesn't apply to unified hierarchy */
return -EOPNOTSUPP;
r = cg_get_path(controller, NULL, "notify_on_release", &fs);
@@ -1104,7 +1182,7 @@ int cg_is_empty(const char *controller, const char *path) {
}
int cg_is_empty_recursive(const char *controller, const char *path) {
- int unified, r;
+ int r;
assert(path);
@@ -1112,11 +1190,10 @@ int cg_is_empty_recursive(const char *controller, const char *path) {
if (controller && (isempty(path) || path_equal(path, "/")))
return false;
- unified = cg_unified(controller);
- if (unified < 0)
- return unified;
-
- if (unified > 0) {
+ r = cg_unified_controller(controller);
+ if (r < 0)
+ return r;
+ if (r > 0) {
_cleanup_free_ char *t = NULL;
/* On the unified hierarchy we can check empty state
@@ -1833,6 +1910,9 @@ bool cg_controller_is_valid(const char *p) {
if (!p)
return false;
+ if (streq(p, SYSTEMD_CGROUP_CONTROLLER))
+ return true;
+
s = startswith(p, "name=");
if (s)
p = s;
@@ -1986,7 +2066,7 @@ int cg_get_keyed_attribute(const char *controller, const char *path, const char
int cg_create_everywhere(CGroupMask supported, CGroupMask mask, const char *path) {
CGroupController c;
- int r, unified;
+ int r;
/* This one will create a cgroup in our private tree, but also
* duplicate it in the trees specified in mask, and remove it
@@ -1998,10 +2078,10 @@ int cg_create_everywhere(CGroupMask supported, CGroupMask mask, const char *path
return r;
/* If we are in the unified hierarchy, we are done now */
- unified = cg_all_unified();
- if (unified < 0)
- return unified;
- if (unified > 0)
+ r = cg_all_unified();
+ if (r < 0)
+ return r;
+ if (r > 0)
return 0;
/* Otherwise, do the same in the other hierarchies */
@@ -2022,16 +2102,16 @@ int cg_create_everywhere(CGroupMask supported, CGroupMask mask, const char *path
int cg_attach_everywhere(CGroupMask supported, const char *path, pid_t pid, cg_migrate_callback_t path_callback, void *userdata) {
CGroupController c;
- int r, unified;
+ int r;
r = cg_attach(SYSTEMD_CGROUP_CONTROLLER, path, pid);
if (r < 0)
return r;
- unified = cg_all_unified();
- if (unified < 0)
- return unified;
- if (unified > 0)
+ r = cg_all_unified();
+ if (r < 0)
+ return r;
+ if (r > 0)
return 0;
for (c = 0; c < _CGROUP_CONTROLLER_MAX; c++) {
@@ -2072,7 +2152,7 @@ int cg_attach_many_everywhere(CGroupMask supported, const char *path, Set* pids,
int cg_migrate_everywhere(CGroupMask supported, const char *from, const char *to, cg_migrate_callback_t to_callback, void *userdata) {
CGroupController c;
- int r = 0, unified;
+ int r = 0, q;
if (!path_equal(from, to)) {
r = cg_migrate_recursive(SYSTEMD_CGROUP_CONTROLLER, from, SYSTEMD_CGROUP_CONTROLLER, to, CGROUP_REMOVE);
@@ -2080,10 +2160,10 @@ int cg_migrate_everywhere(CGroupMask supported, const char *from, const char *to
return r;
}
- unified = cg_all_unified();
- if (unified < 0)
- return unified;
- if (unified > 0)
+ q = cg_all_unified();
+ if (q < 0)
+ return q;
+ if (q > 0)
return r;
for (c = 0; c < _CGROUP_CONTROLLER_MAX; c++) {
@@ -2107,16 +2187,16 @@ int cg_migrate_everywhere(CGroupMask supported, const char *from, const char *to
int cg_trim_everywhere(CGroupMask supported, const char *path, bool delete_root) {
CGroupController c;
- int r, unified;
+ int r, q;
r = cg_trim(SYSTEMD_CGROUP_CONTROLLER, path, delete_root);
if (r < 0)
return r;
- unified = cg_all_unified();
- if (unified < 0)
- return unified;
- if (unified > 0)
+ q = cg_all_unified();
+ if (q < 0)
+ return q;
+ if (q > 0)
return r;
for (c = 0; c < _CGROUP_CONTROLLER_MAX; c++) {
@@ -2133,16 +2213,16 @@ int cg_trim_everywhere(CGroupMask supported, const char *path, bool delete_root)
int cg_mask_supported(CGroupMask *ret) {
CGroupMask mask = 0;
- int r, unified;
+ int r;
/* Determines the mask of supported cgroup controllers. Only
* includes controllers we can make sense of and that are
* actually accessible. */
- unified = cg_all_unified();
- if (unified < 0)
- return unified;
- if (unified > 0) {
+ r = cg_all_unified();
+ if (r < 0)
+ return r;
+ if (r > 0) {
_cleanup_free_ char *root = NULL, *controllers = NULL, *path = NULL;
const char *c;
@@ -2262,7 +2342,18 @@ int cg_kernel_controllers(Set *controllers) {
static thread_local CGroupUnified unified_cache = CGROUP_UNIFIED_UNKNOWN;
-static int cg_update_unified(void) {
+/* The hybrid mode was initially implemented in v232 and simply mounted cgroup v2 on /sys/fs/cgroup/systemd. This
+ * unfortunately broke other tools (such as docker) which expected the v1 "name=systemd" hierarchy on
+ * /sys/fs/cgroup/systemd. From v233 and on, the hybrid mode mountnbs v2 on /sys/fs/cgroup/unified and maintains
+ * "name=systemd" hierarchy on /sys/fs/cgroup/systemd for compatibility with other tools.
+ *
+ * To keep live upgrade working, we detect and support v232 layout. When v232 layout is detected, to keep cgroup v2
+ * process management but disable the compat dual layout, we return %true on
+ * cg_unified_controller(SYSTEMD_CGROUP_CONTROLLER) and %false on cg_hybrid_unified().
+ */
+static thread_local bool unified_systemd_v232;
+
+static int cg_unified_update(void) {
struct statfs fs;
@@ -2280,54 +2371,83 @@ static int cg_update_unified(void) {
if (F_TYPE_EQUAL(fs.f_type, CGROUP2_SUPER_MAGIC))
unified_cache = CGROUP_UNIFIED_ALL;
else if (F_TYPE_EQUAL(fs.f_type, TMPFS_MAGIC)) {
- if (statfs("/sys/fs/cgroup/systemd/", &fs) < 0)
- return -errno;
-
- unified_cache = F_TYPE_EQUAL(fs.f_type, CGROUP2_SUPER_MAGIC) ?
- CGROUP_UNIFIED_SYSTEMD : CGROUP_UNIFIED_NONE;
+ if (statfs("/sys/fs/cgroup/unified/", &fs) == 0 &&
+ F_TYPE_EQUAL(fs.f_type, CGROUP2_SUPER_MAGIC)) {
+ unified_cache = CGROUP_UNIFIED_SYSTEMD;
+ unified_systemd_v232 = false;
+ } else if (statfs("/sys/fs/cgroup/systemd/", &fs) == 0 &&
+ F_TYPE_EQUAL(fs.f_type, CGROUP2_SUPER_MAGIC)) {
+ unified_cache = CGROUP_UNIFIED_SYSTEMD;
+ unified_systemd_v232 = true;
+ } else {
+ if (statfs("/sys/fs/cgroup/systemd/", &fs) < 0)
+ return -errno;
+ if (!F_TYPE_EQUAL(fs.f_type, CGROUP_SUPER_MAGIC))
+ return -ENOMEDIUM;
+ unified_cache = CGROUP_UNIFIED_NONE;
+ }
} else
return -ENOMEDIUM;
return 0;
}
-int cg_unified(const char *controller) {
-
+int cg_unified_controller(const char *controller) {
int r;
- r = cg_update_unified();
+ r = cg_unified_update();
if (r < 0)
return r;
- if (streq_ptr(controller, SYSTEMD_CGROUP_CONTROLLER))
- return unified_cache >= CGROUP_UNIFIED_SYSTEMD;
- else
- return unified_cache >= CGROUP_UNIFIED_ALL;
+ if (unified_cache == CGROUP_UNIFIED_NONE)
+ return false;
+
+ if (unified_cache >= CGROUP_UNIFIED_ALL)
+ return true;
+
+ return streq_ptr(controller, SYSTEMD_CGROUP_CONTROLLER);
}
int cg_all_unified(void) {
+ int r;
+
+ r = cg_unified_update();
+ if (r < 0)
+ return r;
- return cg_unified(NULL);
+ return unified_cache >= CGROUP_UNIFIED_ALL;
}
-void cg_unified_flush(void) {
+int cg_hybrid_unified(void) {
+ int r;
+
+ r = cg_unified_update();
+ if (r < 0)
+ return r;
+
+ return unified_cache == CGROUP_UNIFIED_SYSTEMD && !unified_systemd_v232;
+}
+
+int cg_unified_flush(void) {
unified_cache = CGROUP_UNIFIED_UNKNOWN;
+
+ return cg_unified_update();
}
int cg_enable_everywhere(CGroupMask supported, CGroupMask mask, const char *p) {
_cleanup_free_ char *fs = NULL;
CGroupController c;
- int r, unified;
+ int r;
assert(p);
if (supported == 0)
return 0;
- unified = cg_all_unified();
- if (unified < 0)
- return unified;
- if (!unified) /* on the legacy hiearchy there's no joining of controllers defined */
+ r = cg_all_unified();
+ if (r < 0)
+ return r;
+ if (r == 0) /* on the legacy hiearchy there's no joining of controllers defined */
return 0;
r = cg_get_path(SYSTEMD_CGROUP_CONTROLLER, p, "cgroup.subtree_control", &fs);
@@ -2359,63 +2479,69 @@ int cg_enable_everywhere(CGroupMask supported, CGroupMask mask, const char *p) {
bool cg_is_unified_wanted(void) {
static thread_local int wanted = -1;
- int r, unified;
+ int r;
bool b;
+ const bool is_default = DEFAULT_HIERARCHY == CGROUP_UNIFIED_ALL;
- /* If the hierarchy is already mounted, then follow whatever
- * was chosen for it. */
- unified = cg_all_unified();
- if (unified >= 0)
- return unified;
-
- /* Otherwise, let's see what the kernel command line has to
- * say. Since checking that is expensive, let's cache the
- * result. */
+ /* If we have a cached value, return that. */
if (wanted >= 0)
return wanted;
+ /* If the hierarchy is already mounted, then follow whatever
+ * was chosen for it. */
+ if (cg_unified_flush() >= 0)
+ return (wanted = unified_cache >= CGROUP_UNIFIED_ALL);
+
+ /* Otherwise, let's see what the kernel command line has to say.
+ * Since checking is expensive, cache a non-error result. */
r = proc_cmdline_get_bool("systemd.unified_cgroup_hierarchy", &b);
- if (r < 0)
- return false;
- return (wanted = r > 0 ? b : false);
+ return (wanted = r > 0 ? b : is_default);
}
bool cg_is_legacy_wanted(void) {
- return !cg_is_unified_wanted();
+ static thread_local int wanted = -1;
+
+ /* If we have a cached value, return that. */
+ if (wanted >= 0)
+ return wanted;
+
+ /* Check if we have cgroups2 already mounted. */
+ if (cg_unified_flush() >= 0 &&
+ unified_cache == CGROUP_UNIFIED_ALL)
+ return (wanted = false);
+
+ /* Otherwise, assume that at least partial legacy is wanted,
+ * since cgroups2 should already be mounted at this point. */
+ return (wanted = true);
}
-bool cg_is_unified_systemd_controller_wanted(void) {
+bool cg_is_hybrid_wanted(void) {
static thread_local int wanted = -1;
- int r, unified;
+ int r;
bool b;
+ const bool is_default = DEFAULT_HIERARCHY >= CGROUP_UNIFIED_SYSTEMD;
+ /* We default to true if the default is "hybrid", obviously,
+ * but also when the default is "unified", because if we get
+ * called, it means that unified hierarchy was not mounted. */
- /* If the unified hierarchy is requested in full, no need to
- * bother with this. */
- if (cg_is_unified_wanted())
- return 0;
+ /* If we have a cached value, return that. */
+ if (wanted >= 0)
+ return wanted;
/* If the hierarchy is already mounted, then follow whatever
* was chosen for it. */
- unified = cg_unified(SYSTEMD_CGROUP_CONTROLLER);
- if (unified >= 0)
- return unified;
-
- /* Otherwise, let's see what the kernel command line has to
- * say. Since checking that is expensive, let's cache the
- * result. */
- if (wanted >= 0)
- return wanted;
+ if (cg_unified_flush() >= 0 &&
+ unified_cache == CGROUP_UNIFIED_ALL)
+ return (wanted = false);
+ /* Otherwise, let's see what the kernel command line has to say.
+ * Since checking is expensive, cache a non-error result. */
r = proc_cmdline_get_bool("systemd.legacy_systemd_cgroup_controller", &b);
- if (r < 0)
- return false;
-
- return (wanted = r > 0 ? b : false);
-}
-bool cg_is_legacy_systemd_controller_wanted(void) {
- return cg_is_legacy_wanted() && !cg_is_unified_systemd_controller_wanted();
+ /* The meaning of the kernel option is reversed wrt. to the return value
+ * of this function, hence the negation. */
+ return (wanted = r > 0 ? !b : is_default);
}
int cg_weight_parse(const char *s, uint64_t *ret) {
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